HK1152996B

HK1152996B - Exposure apparatus, exposure method and method for making assembly

Info

Publication number: HK1152996B
Application number: HK11106945.0A
Authority: HK
Inventors: 柴崎佑一
Original assignee: 株式会社尼康
Priority date: 2006-02-21
Filing date: 2011-07-06
Publication date: 2012-12-07

Description

Exposure apparatus, exposure method, and device manufacturing method

The present application is a divisional application of an invention patent application having an application number of 200780005155.2, an application date of 2007, 2/21, and an invention name of "pattern forming apparatus, mark detecting apparatus, exposure apparatus, pattern forming method, exposure method, and device manufacturing method".

Technical Field

The present invention relates to a pattern forming apparatus, a mark detecting apparatus, an exposure apparatus, a pattern forming method, an exposure method, and a device manufacturing method, and more particularly, to a pattern forming apparatus and an exposure apparatus which can be suitably used in manufacturing electronic devices such as semiconductor devices and liquid crystal display devices, a mark detecting apparatus which can be suitably used in the pattern forming apparatus or the exposure apparatus, a pattern forming method and an exposure method which can be suitably used in manufacturing the electronic devices, and a device manufacturing method using the pattern forming method or the exposure method.

Background

Conventionally, in a photolithography process for manufacturing electronic components (micro-components) such as semiconductor devices (integrated circuits and the like) and liquid crystal display devices, a projection exposure apparatus of a step-and-repeat system (a so-called stepper), a projection exposure apparatus of a step-and-scan system (a so-called scanning stepper (also called a scanner)) and the like have been mainly used.

However, in a photolithography process for manufacturing a semiconductor element or the like, a plurality of circuit patterns are formed on a wafer in an overlapping manner, but if the accuracy of the overlapping between the layers is low, the semiconductor element or the like cannot exhibit predetermined circuit characteristics, and may be a defective product. Therefore, usually, a mark (alignment mark) is attached to each of a plurality of irradiation regions on a wafer in advance, and the position (coordinate value) of the mark on the stage coordinate system of the exposure apparatus is detected. Thereafter, wafer alignment for aligning an irradiated area on the wafer with a newly formed pattern (e.g., a reticle pattern) is performed based on the mark position information and the known position information of the pattern.

As a method of wafer alignment, full wafer alignment is mainly used. The full wafer alignment is performed by detecting only alignment marks of a plurality of irradiation regions (also referred to as a sampling irradiation region or an alignment irradiation region) on a wafer while taking into consideration processing capability, and determining regularity of an arrangement of the irradiation regions, thereby aligning each irradiation region. In particular, recently, enhanced full wafer alignment (EGA) in which the arrangement of shot regions on a wafer is precisely calculated by a statistical method has become the mainstream (for example, see patent document 1).

However, since the requirement for overlay accuracy is becoming more stringent as the integrated circuit becomes more precise, and the calculation accuracy of EGA is also required to be improved, the number of sampling irradiation regions, that is, the number of labels to be detected must be increased.

Further, the wafer surface is not necessarily flat due to, for example, nonuniformity of resist film thickness and wafer waviness. Therefore, in particular, in a scanning exposure apparatus such as a scanner, when a reticle pattern is transferred to an irradiation region on a wafer by a scanning exposure method, positional information (focus information) of a wafer surface in an optical axis direction of a projection optical system among a plurality of detection points set in an exposure region where an image of the reticle pattern is projected via the projection optical system is detected by using a multi-focus position detection system or the like, and based on the detection result, the position and inclination of a stage or stage for holding the wafer in the optical axis direction are controlled so that the wafer surface coincides with the projection optical system in the exposure region (or becomes a depth of focus range of the projection optical system), that is, so-called focus leveling control is performed (for example, see patent document 2).

However, since increasing the number of the sampled irradiation regions of the EGA reduces the throughput of the exposure apparatus, it is actually difficult to adopt a method of simply increasing the number of the sampled irradiation regions.

In addition, in the conventional exposure apparatus, since the wafer alignment (detection of the mark) operation and the focus information detection operation are different in purpose from each other, the operations are performed in a manner unrelated to each other without considering the relationship between the operations.

However, in the future, semiconductor devices are being more highly integrated, and circuit patterns formed on wafers are being more precisely formed, so that exposure apparatuses for mass production of semiconductor devices are required to have further improved device performance and further improved throughput for forming the precise patterns.

[ patent document 1 ] Japanese patent application laid-open No. Sho 61-44429

[ patent document 2 ] Japanese patent application laid-open No. 6-283403

Disclosure of Invention

The present invention has been made in view of the above circumstances, and in view of point 1, there is provided a pattern forming apparatus 1 for forming a pattern on an object, the apparatus including: a movable body which is held at a plurality of positions different from each other, moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis, and on which marks are formed; a plurality of mark detection systems, which are provided with detection areas separately in a direction parallel to the 2 nd axis and detect different marks on the object respectively; and a surface position detection device that irradiates the object with a detection beam and receives reflected light of the detection beam, and detects surface position information of the object at a plurality of detection points having different positions in a direction parallel to the 2 nd axis.

Accordingly, the surface position detection device detects surface position information of a plurality of detection points having different positions in a direction parallel to the 2 nd axis of the object, and the mark detection systems, each having a detection area arranged separately in a direction parallel to the 2 nd axis, detect different marks on the object. This makes it possible to perform the mark detection operation and the surface position information (focus information) detection operation in a short time.

The invention according to claim 2 is a pattern forming apparatus for forming a pattern on an object, comprising: a moving body which holds the object, moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis, and has a pair of 1 st gratings on one surface thereof, the 1 st gratings having a lattice whose periodic direction is a direction parallel to the 1 st axis; a plurality of mark detection systems, the positions of the detection areas are different in the direction parallel to the 2 nd axis; and a 1 st shaft encoder having a plurality of 1 st read heads, the 1 st read head including a pair of 1 st read heads disposed one outside each of the plurality of detection regions in a direction parallel to the 2 nd shaft; position information of the movable body in a direction parallel to the 1 st axis is measured by a 1 st head facing at least one of the pair of 1 st gratings.

Accordingly, the 1 st read head of the 1 st axis encoder facing at least one of the pair of 1 st gratings measures the positional information of the movable body in the direction parallel to the 1 st axis. In this case, since the pair of 1 st read heads are disposed on both outer sides of the plurality of mark detection systems, when the movable body moves in the direction parallel to the 1 st axis, the marks on the object can be measured simultaneously by the plurality of mark detection systems.

The 3 rd aspect of the present invention is a pattern forming apparatus for forming a pattern on an object, comprising: a moving body that holds the object and moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis, and that has a 1 st grating and a 2 nd grating on one surface, the 1 st grating having a lattice whose periodic direction is a direction parallel to the 1 st axis, and the 2 nd grating having a lattice whose periodic direction is a direction parallel to the 2 nd axis; at least one mark detection system for detecting marks on said object; a measuring device including a 1 st shaft encoder and a 2 nd shaft encoder, the 1 st shaft encoder including a plurality of 1 st read heads whose positions are different in a direction parallel to the 2 nd shaft, the 1 st read head facing the 1 st grating measuring positional information of the movable body in the direction parallel to the 1 st shaft, the 2 nd shaft encoder including a plurality of 2 nd read heads whose positions are different in a direction parallel to the 1 st shaft, the 2 nd read head facing the 2 nd grating measuring positional information of the movable body in the direction parallel to the 2 nd shaft; and a control device that controls a position of the movable body based on a measurement value of the measurement device, and detects a mark on the object using the mark detection system.

Accordingly, the control device controls the position of the movable body based on the measurement value of the measurement device, and detects the mark on the object mounted on the movable body using the mark detection system. That is, it is possible to detect the mark on the object using the mark detection system while controlling the position of the moving body with high accuracy based on the measurement values of the 1 st read head of the 1 st axis encoder facing the 1 st grating and the 2 nd read head of the 2 nd axis encoder facing the 2 nd grating.

The 4 th aspect of the present invention is a 4 th pattern forming apparatus for forming a pattern on an object, including: a movable body that holds an object having marks formed at a plurality of different positions, and that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and a plurality of mark detection systems, each of which has a detection region arranged at a different position in a direction parallel to the 2 nd axis and detects marks at different positions on the object, wherein the number of marks on the object detected by the plurality of mark detection systems at the same time is different depending on the position of the movable body in the plane.

Accordingly, since the number of marks on the object to be simultaneously detected by the plurality of mark detection systems is different depending on the position of the moving body on which the object is mounted within the predetermined plane, when the moving body is moved in the direction intersecting the 2 nd axis, for example, in the direction parallel to the 1 st axis (or in the direction orthogonal to the 2 nd axis), the marks at positions different from each other on the object can be simultaneously detected by using a required number of mark detection systems depending on the position of the moving body in the intersecting direction of the 2 nd axis, that is, depending on the arrangement of the divisional areas on the object.

The 5 th aspect of the present invention is a 5 th patterning device for forming a pattern on an object using an optical system, including: a movable body that holds an object and moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; a mark detection system that detects a plurality of marks formed on the object; an adjusting device for adjusting the optical characteristics of the optical system; and a control device for controlling the adjustment device so as to adjust the optical characteristics based on the detection results of the plurality of marks on the object detected by the mark detection system so far when the mark to be detected by the mark detection system remains on the object.

In this way, the control device controls the adjusting device to adjust the optical characteristics of the optical system based on the detection results of the plurality of marks on the object detected by the mark detecting system so far when the mark to be detected by the mark detecting system remains on the object. Therefore, even if the image of the mark is shifted in accordance with the adjustment after the adjustment of the optical characteristics of the optical system, for example, when the detection of the image of the mark (or pattern) of the optical system is performed, the image of the mark after the shift is measured, and as a result, the shift of the image of the mark in accordance with the adjustment of the optical characteristics of the optical system does not become a factor of the measurement error. In addition, since the adjustment is started before all the marks to be detected are detected, that is, based on the detection results of the marks detected so far, the time required for the adjustment can be made to overlap the detection time of the remaining marks, and thus the throughput can be improved compared with the conventional technique in which the adjustment is started after all the marks are detected.

The 6 th aspect of the present invention is a 6 th patterning device that projects a pattern onto an object using an optical system, including: a movable body that holds the object and moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; a mark detection system that detects a mark on the object mounted on the movable body; and a control device that performs a mark detection operation on the object during a period from when a measurement operation of a positional relationship between a projection position of the pattern image and a detection center of the mark detection system by the optical system is started to when the measurement operation is ended.

In this way, the control device performs the marker detection operation on the object mounted on the movable body after the start of the measurement operation of the positional relationship between the projection position of the pattern image and the detection center of the marker detection system by the optical system until the end of the measurement operation. In this way, at least a part of the detection operation of the mark detection system for the plurality of marks to be detected formed on the object can be ended at the time point when the measurement operation of the positional relationship is ended. This makes it possible to improve the processing compared to a case where the detection operation of the plurality of marks by the mark detection system is performed before or after the measurement operation of the positional relationship.

The 7 th aspect of the present invention is a 7 th patterning device for projecting a pattern onto an object using an optical system, comprising: a movable body that holds the object and moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; a mark detection system that detects a mark on the object mounted on the movable body; and a control device that performs an operation of measuring a positional relationship between a projected position of the pattern image and a detection center of the mark detection system by the optical system, during a period from a start of a detection operation of a plurality of marks to be detected formed on the object to an end of the detection operation.

In this way, the control device performs the operation of measuring the positional relationship between the projection position of the pattern image by the optical system and the detection center of the mark detection system, after the start of the operation of detecting the plurality of marks to be detected formed on the object mounted on the movable body by the plurality of mark detection systems, until the end of the operation. Therefore, the measurement operation of the positional relationship can be ended while the detection operation of the mark detection system is performed with respect to the plurality of marks to be detected formed on the object. This can improve the throughput compared to the case where the measurement operation of the positional relationship is performed before or after the detection operation of the plurality of marks to be detected formed on the object by the mark detection system.

An 8 th aspect of the present invention is an 8 th pattern forming apparatus for forming a pattern on an object, including: a 1 st moving body that holds the object and moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; a 2 nd movable body that moves independently of the 1 st movable body in the plane; a mark detection system that detects a plurality of marks to be detected formed on the object mounted on the 1 st movable body; and a control device that controls the two movable bodies so as to switch between an approaching state in which the 1 st movable body and the 2 nd movable body are brought close to each other by a predetermined distance or less and a separating state in which the two movable bodies are separated from each other, wherein the control device performs the switching operation of the states after a plurality of mark detection operations to be detected formed on the object are started until the detection operations are completed.

Here, the approaching state in which the 1 st moving body and the 2 nd moving body are brought close to each other by a predetermined distance or less includes a state in which both moving bodies are brought close to each other by a distance of zero, that is, a concept including a state in which both moving bodies are brought into contact with each other.

Accordingly, the control device performs a process between an approaching state in which the 1 st moving body and the 2 nd moving body approach to a predetermined distance or less and a separating state in which the two moving bodies are separated from each other, after the start of a detection operation of a plurality of marks to be detected formed on an object mounted on the 1 st moving body and until the end of the detection operation. Therefore, the state switching operation can be terminated while the detection operation of the plurality of marks to be detected on the object is performed. This makes it possible to improve the throughput compared to the case where the switching operation of the state is performed before or after the detection operation of the plurality of marks to be detected formed on the object.

The 9 th aspect of the present invention is a 9 th pattern forming apparatus for forming a pattern on an object, including: a movable body that holds an object having marks formed at a plurality of different positions, and that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; a plurality of mark detection systems that respectively detect marks at different positions on the object; a focus position changing device that simultaneously changes relative positional relationships in an optical axis direction between the plurality of mark detection systems and the object mounted on the movable body, the plurality of mark detection systems being perpendicular to the plane, between the plurality of mark detection systems; and a control device for simultaneously detecting each of the marks formed at different positions on the object by using a plurality of mark detection systems corresponding to each of the marks while changing a relative positional relationship in the focusing direction by the focus position changing device.

Accordingly, the control device simultaneously detects the marks formed at different positions on the object by using the plurality of mark detection systems corresponding to the marks while changing the relative positional relationship in the focusing direction perpendicular to the predetermined plane between the plurality of mark detection systems and the object mounted on the movable body by the focusing position changing device. Thus, by preferentially using the mark detection result in the best focus state in each mark detection system, it is possible to detect marks formed at different positions on the object with good accuracy, without being affected by the unevenness on the surface of the object and the difference in the best focus of each mark detection system.

A 10 th aspect of the present invention is a 1 st exposure apparatus for exposing an object with an energy beam, comprising: a movable body that holds the object and is movable in the 1 st and 2 nd directions within a predetermined plane; a mark detection system having a plurality of detection regions at different positions in the 2 nd direction; and a detection device having a detection area at a position different from the plurality of detection areas in the 1 st direction, and detecting position information of the object in a 3 rd direction orthogonal to the 1 st and 2 nd directions among a plurality of detection points at positions different from the 2 nd direction.

Accordingly, when the moving body is moved in parallel in the 1 st direction, the detection of the plurality of marks on the moving body or the object by the plurality of mark detection systems and the detection of the object surface position information at the plurality of detection points by the detection device can be performed.

An 11 th aspect of the present invention is a 2 nd exposure apparatus for exposing an object with an energy beam, comprising: a movable body which can hold the object and move in the 1 st and 2 nd directions in a predetermined plane, and which is provided with a pair of 1 st cell parts in which cells are periodically arranged in the 1 st direction on a surface substantially parallel to the plane; a mark detection system having a plurality of detection regions that are positioned differently in the 2 nd direction; and a measuring device including a 1 st encoder, the 1 st encoder including a plurality of 1 st read heads including a pair of 1 st read heads disposed so as to sandwich the plurality of detection regions in the 2 nd direction, the 1 st read head opposing at least one of the pair of 1 st cells measuring positional information of the moving body in the 1 st direction.

Accordingly, the 1 st reading head of the 1 st encoder facing at least one of the 1 st lattice sections measures the positional information of the moving body in the 1 st direction. In this case, since the pair of 1 st reading heads are disposed so as to sandwich the plurality of detection regions, when the movable body moves in the 1 st direction, the marks on the object can be simultaneously measured by the plurality of mark detection systems.

A 12 th aspect of the present invention is a 3 rd exposure apparatus for exposing an object with an energy beam, comprising: a movable body capable of holding the object and moving in the 1 st and 2 nd directions in a predetermined plane; and a mark detection system having detection regions different in position in the 2 nd direction and capable of simultaneously detecting a plurality of marks on the object; the movable body moves in the 1 st direction, the marks having different positions in the 1 st direction on the object are detected by the mark detection system, and the number of the marks detected by the plurality of mark detection systems is different depending on the position of the object in the 1 st direction.

Accordingly, when the moving body is moved in the 1 st direction, the marks at different positions on the object can be simultaneously detected using a required number of mark detection systems depending on the position of the moving body in the 1 st direction, that is, depending on the arrangement of the divisional areas on the object.

A 13 th aspect of the present invention is a 4 th exposure apparatus for exposing an object with an energy beam, comprising: a moving body which holds the object, is movable in the 1 st and 2 nd directions in a predetermined plane, and has a lattice section in which lattices are periodically arranged on a surface substantially parallel to the plane; a mark detection system for detecting a mark on the object; and a measuring device having an encoder having a plurality of heads whose positions are different in a direction intersecting the grid arrangement direction, wherein when the mark is detected, positional information of the movable body in the arrangement direction is measured by the heads facing the grid.

Accordingly, when the mark detection operation on the object is performed, the encoder of the measuring device measures the positional information of the moving body in the grid arrangement direction of the grid section. That is, the position of the moving body is controlled with high accuracy based on the measurement value of the reading head of the encoder facing the lattice section, and the mark on the object is detected using the mark detection system.

A 14 th aspect of the present invention is a 5 th exposure apparatus for exposing an object with an energy beam via an optical system, comprising: a movable body that holds the object so as to be movable in the 1 st and 2 nd directions in a predetermined plane; a mark detection system for detecting a mark on the object; an adjusting device for adjusting the optical characteristics of the optical system; and a control device that controls the adjustment device based on a result of detection of a part of the plurality of marks by the mark detection system during a detection operation of the plurality of marks on the object by the mark detection system.

In this way, the control device controls the adjusting device to adjust the optical characteristics of the optical system based on the detection result of a part of the plurality of marks on the object detected by the mark detecting system during the detection operation of the plurality of marks on the object by the mark detecting system.

A 15 th aspect of the present invention is a 6 th exposure apparatus for exposing an object with a pattern illuminated with an energy beam via an optical system, comprising: a movable body that holds the object so as to be movable in the 1 st and 2 nd directions in a predetermined plane; a mark detection system for detecting a mark on the object; and a control device that simultaneously performs at least a part of the measurement operation of the positional relationship between the projected position of the pattern and the detection center of the mark detection system and the detection operation of the mark by the mark detection system, with the other operation.

This can improve the throughput compared to the case where the detection operation of the marker detection system for the marker is performed before or after the measurement operation of the positional relationship.

A 16 th aspect of the present invention is a 7 th exposure apparatus for exposing an object with an energy beam, comprising: a movable body that holds the object so as to be movable in the 1 st and 2 nd directions in a predetermined plane; a mark detection system for detecting a mark on the object; and a control device capable of setting a 1 st state in which the movable body and another movable body different from the movable body approach each other at a predetermined distance or less and a 2 nd state in which the movable bodies are separated from each other, and capable of switching between the 1 st and 2 nd states during a detection operation of the mark by the mark detection system.

Accordingly, the control device performs a switching operation between a 1 st state in which the movable body approaches another movable body by a predetermined distance or less and a 2 nd state in which the movable bodies are separated from each other in the detection operation of the mark on the object by the mark detection system. Therefore, the state switching operation can be terminated while the detection operation of the plurality of marks to be detected on the object is performed. This can improve the throughput compared to the case where the switching operation of the state is performed before or after the mark detection operation on the object.

A 17 th aspect of the present invention is an 8 th exposure apparatus for exposing an object held by a movable body movable in 1 st and 2 nd directions in a predetermined plane with an energy beam, comprising: a mark detection system having a plurality of detection regions at different positions in the 2 nd direction; and a reference member that is formed with a plurality of reference marks that can be simultaneously detected by the mark detection system and that can be moved in the 1 st direction from the opposite side of the plurality of detection regions to the positions of the plurality of detection regions with the irradiation position of the energy beam therebetween.

Accordingly, the reference member can be moved in the 1 st direction from the 1 st position on the opposite side of the plurality of detection regions of the mark detection system to the positions (the 2 nd position) of the plurality of detection regions with the irradiation position of the energy beam therebetween to detect the plurality of reference marks on the reference member using the mark detection system. Thereafter, the movable body is moved to the 1 st position integrally with the reference member. A plurality of markers on the object may be detected using a marker detection system en route to the path of travel.

An 18 th aspect of the present invention is a method of manufacturing a 1 st device, comprising: a step of exposing an object using the exposure apparatus according to any one of claims 44 to 87; and developing the exposed object.

A 19 th aspect of the present invention is a 1 st mark detection device for detecting a mark on an object, the device including: a mark detection system for detecting a mark on an object mounted on a moving body which is movable in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis and has a 1 st grating and a 2 nd grating on one surface thereof, the 1 st grating having a lattice whose periodic direction is a direction parallel to the 1 st axis, the 2 nd grating having a lattice whose periodic direction is a direction parallel to the 2 nd axis; a measuring device including a 1 st shaft encoder and a 2 nd shaft encoder, the 1 st shaft encoder including a plurality of 1 st read heads having different positions in a direction parallel to the 2 nd shaft, the 1 st read head facing the 1 st grating measuring positional information of the moving body in the direction parallel to the 1 st shaft, the 2 nd shaft encoder including a plurality of 2 nd read heads having different positions in the direction parallel to the 1 st shaft, the 2 nd read head facing the 2 nd grating measuring positional information of the moving body in the direction parallel to the 2 nd shaft; and a control device that controls a position of the movable body based on a measurement value measured by the measurement device, and detects a mark on the object using the mark detection system.

Accordingly, the position of the movable body is controlled by the control device based on the measurement value of the measurement device, and the mark on the object mounted on the movable body is detected by the mark detection system. That is, it is possible to detect the mark on the object using the mark detection system while controlling the position of the moving body with high accuracy based on the measurement values of the 1 st read head of the 1 st axis encoder facing the 1 st grating and the 2 nd read head of the 2 nd axis encoder facing the 2 nd grating.

A 20 th aspect of the present invention is a 2 nd mark detection device for detecting a mark on an object, including: a movable body that holds an object having marks formed at a plurality of different positions, and that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and a plurality of mark detection systems having detection regions whose positions are different in a direction parallel to the 2 nd axis, the mark detection systems being capable of simultaneously detecting marks at positions different from each other on the object, the number of marks on the object simultaneously detected by the plurality of mark detection systems being different depending on a position of the moving body on which the object is mounted in the plane.

Accordingly, since the number of marks on the object to be simultaneously detected by the plurality of mark detection systems is different depending on the position of the moving body on which the object is mounted within the predetermined plane, when the moving body is moved in the direction intersecting the 2 nd axis, for example, in the direction parallel to the 1 st axis (or in the direction orthogonal to the 2 nd axis), the marks at positions different from each other on the object can be simultaneously detected by using a required number of mark detection systems depending on the position of the moving body in the direction intersecting the 2 nd axis.

A 21 st aspect of the present invention is a 3 rd mark detection device for detecting a mark on an object, including: a movable body that holds an object having marks formed at a plurality of different positions, and that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; a plurality of mark detection systems that respectively detect marks at different positions on the object; a focus position changing device that simultaneously changes relative positional relationships in an optical axis direction between the plurality of mark detection systems and the object mounted on the movable body, the plurality of mark detection systems being perpendicular to the plane, between the plurality of mark detection systems; and a control device for simultaneously detecting each mark formed at a different position on the object by using a plurality of mark detection systems corresponding to each mark while changing the relative positional relationship in the focusing direction by the focusing position changing device.

The 22 st aspect of the present invention is a 1 st pattern forming method of forming a pattern on an object, comprising: a detection step of detecting a mark on an object mounted on a movable body which moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis and on one surface of which a 1 st grating and a 2 nd grating are provided, the 1 st grating having a grating whose direction parallel to the 1 st axis is a periodic direction, the 2 nd grating having a grating whose direction parallel to the 2 nd axis is a periodic direction, the detection step controlling a position of the movable body based on a measurement value of the measurement device at a time of detection of the mark, the measurement device having a 1 st axis encoder and a 2 nd axis encoder, the 1 st axis encoder having a plurality of 1 st read heads whose positions are different in a direction parallel to the 2 nd axis, and measuring positional information of the movable body in the direction parallel to the 1 st axis by a 1 st read head facing the 1 st grating, the 2 nd-axis encoder includes a plurality of 2 nd read heads having different positions in a direction parallel to the 1 st axis, and measures positional information of the movable body in the direction parallel to the 2 nd axis by the 2 nd read head facing the 2 nd grating.

Accordingly, it is possible to detect the mark on the object using the mark detection system while controlling the position of the moving body with high accuracy based on the measurement values of the 1 st read head of the 1 st axis encoder facing the 1 st grating and the 2 nd read head of the 2 nd axis encoder facing the 2 nd grating.

The 23 rd aspect of the present invention is a 2 nd pattern forming method for forming a pattern on an object, comprising: loading the object having the marks formed at a plurality of different positions on a movable body that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and simultaneously detecting marks at positions different from each other on the object using a plurality of mark detection systems arranged at positions different from each other in a detection region in a direction parallel to the 2 nd axis, wherein the number of marks on the object simultaneously detected by the plurality of mark detection systems is different depending on the position of the movable body in the plane.

A 24 th aspect of the present invention is a 3 rd pattern forming method for forming a pattern on an object using an optical system, comprising: a step of mounting the object on a movable body that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; detecting a plurality of marks formed on the object using a mark detection system; and adjusting the optical characteristics of the optical system based on the detection results of the plurality of marks on the object detected by the mark detection system up to this point when the mark to be detected by the mark detection system remains on the object.

Accordingly, when the mark to be detected by the mark detection system remains on the object, the optical characteristics of the optical system are adjusted based on the detection results of the plurality of marks on the object detected by the mark detection system. Therefore, even if the image of the mark is shifted in accordance with the adjustment after the adjustment of the optical characteristics of the optical system, for example, when the detection of the image of the mark (or pattern) of the optical system is performed, the image of the mark after the shift is measured, and as a result, the shift of the image of the mark in accordance with the adjustment of the optical characteristics of the optical system does not become a factor of the measurement error. Further, since the adjustment is started before all the marks to be detected are detected, that is, based on the detection result of the marks detected so far, the time required for the adjustment can be made to overlap the detection time of the remaining marks, and thus the throughput can be improved compared with the conventional technique in which the adjustment is started after all the marks are detected.

A 25 th aspect of the present invention is a 4 th pattern forming method for projecting a pattern on an object using an optical system, comprising: a step of mounting the object on a movable body that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and performing a mark detection operation on the object during a period from a start of a measurement operation of a positional relationship between a projection position of the pattern image by the optical system and a detection center of the mark detection system to an end of the measurement operation.

Accordingly, the marker detection operation of the marker detection system with respect to the object mounted on the movable body is performed after the measurement operation of the positional relationship between the projection position of the pattern and the detection center of the marker detection system by the optical system is started and until the measurement operation is ended. In this way, at least a part of the detection operation of the mark detection system for the plurality of marks to be detected formed on the object can be ended at the time point when the measurement operation of the positional relationship is ended. This makes it possible to improve the throughput compared to a case where the detection operation of the mark detection system for the plurality of marks is performed before or after the measurement operation of the positional relationship.

A 26 th aspect of the present invention is a 5 th pattern forming method for projecting a pattern on an object using an optical system, comprising: a step of mounting the object on a movable body that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and a step of performing an operation of measuring a positional relationship between a projected position of the pattern image by the optical system and a detection center of the mark detection system, during a period from when an operation of detecting a plurality of marks to be detected formed on the object mounted on the movable body by the mark detection system is started to when the operation is ended.

In this way, the measurement operation of the positional relationship between the pattern projection position by the optical system and the detection center of the mark detection system is performed after the detection operation of the plurality of marks to be detected formed on the object mounted on the movable body by the mark detection system is started and until the detection operation is ended. In this way, the measurement operation of the positional relationship can be ended between the detection operations of the plurality of marks to be detected formed on the object by the mark detection system. As a result, the throughput can be improved more than in the case where the measurement operation of the positional relationship is performed before and after the detection operation of the plurality of marks to be detected formed on the object by the mark detection system.

The 27 th aspect of the present invention is a 6 th pattern forming method for forming a pattern on an object, the method including: a step of mounting the object on a movable body that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and a step of starting a detection operation of a plurality of marks to be detected formed on the object mounted on the 1 st moving body by a mark detection system in an approaching state in which the 1 st moving body and a 2 nd moving body that moves independently of the 1 st moving body within the plane approach by a predetermined distance or less, and controlling the two moving bodies so as to switch the two moving bodies from the approaching state to a separated state in which the two moving bodies are separated from each other before all the detection operations of the plurality of marks are ended.

Accordingly, when the 1 st and 2 nd moving bodies are in an approaching state in which they approach each other by a predetermined distance or less, the detection operation of the mark detection system for the plurality of marks to be detected formed on the object mounted on the 1 st moving body is started, and before all the detection operations of the plurality of marks are completed, the two moving bodies are controlled so as to be switched from the approaching state to a separated state in which they are separated from each other. Therefore, the state switching operation can be terminated while the detection operation of the plurality of marks to be detected formed on the object is performed. This can improve the throughput compared to the case where the switching operation of the above state is performed before or after the detection operation of the plurality of marks to be detected formed on the object.

A 28 th aspect of the present invention is a 7 th pattern forming method for forming a pattern on an object, including: loading the object having the marks formed at a plurality of different positions on a movable body that moves in a predetermined plane including a 1 st axis and a 2 nd axis intersecting the 1 st axis; and simultaneously measuring, between the plurality of mark detection systems, marks formed at mutually different positions on the object by independently using the plurality of mark detection systems corresponding to the marks while simultaneously changing relative positional relationships in the optical axis direction between the plurality of mark detection systems and the object mounted on the movable body and perpendicular to the plane.

Accordingly, the relative positional relationship in the optical axis direction between the plurality of mark detection systems and the object mounted on the movable body, the plurality of mark detection systems being perpendicular to the predetermined plane, is simultaneously changed between the plurality of mark detection systems, and the plurality of mark detection systems corresponding to the respective marks are individually used to simultaneously measure the respective marks formed at different positions on the object. Thus, by preferentially using the mark detection result in the best focus state in each mark detection system, it is possible to detect marks formed at different positions on the object with good accuracy, without being affected by the unevenness on the surface of the object and the difference in the best focus of each mark detection system.

In addition, by forming a pattern on an object by any of the pattern forming methods 1 to 7 of the present invention in a photolithography process and subjecting the object on which the pattern is formed to a treatment, the pattern can be formed on the object with good accuracy, whereby a microdevice with higher integration can be manufactured with high yield.

The present invention, from the 29 th viewpoint, is a step of forming a pattern on an object using the pattern forming method described in any one of claims 92 to 100; and a step of processing the object on which the pattern is formed.

A 30 th aspect of the present invention is a 1 st exposure method of exposing an object with an energy beam, comprising: a 1 st step of mounting the object on a movable body movable in 1 st and 2 nd directions on a predetermined plane; a 2 nd step of detecting a mark on the object by using a mark detection system having a plurality of detection regions different in position in the 2 nd direction; and a 3 rd step of detecting positional information of the object in a 3 rd direction orthogonal to the 1 st and 2 nd directions using a detection device having a detection area at a position different from the plurality of detection areas in the 1 st direction and having a plurality of detection points at positions different from the 2 nd direction.

A 31 st aspect of the present invention is a 2 nd exposure method of exposing an object with an energy beam, comprising: a 1 st step of mounting the object on a movable body movable in 1 st and 2 nd directions on a predetermined plane; and a 2 nd step of measuring a mark on the object using a mark detection system having a plurality of detection regions different in position in the 2 nd direction, using a measurement device including a 1 st encoder, the 1 st encoder having a plurality of 1 st read heads including a pair of 1 st read heads disposed so as to sandwich the plurality of detection regions in the 2 nd direction, and measuring positional information of the moving body in the 1 st direction by the 1 st read head facing at least one of the pair of 1 st lattice sections, the pair of 1 st lattice sections being provided on a surface substantially parallel to the plane of the moving body and having lattices periodically arranged in the 1 st direction, respectively.

Accordingly, for example, when the movable body is moved in the 1 st direction, the marks on the object can be measured simultaneously by the plurality of mark detection systems. Further, positional information of the moving body in the 1 st direction is measured by the 1 st head of the 1 st encoder facing at least one of the pair of 1 st lattices.

A 32 th aspect of the present invention is a 3 rd exposure method of exposing an object with an energy beam, comprising: a 1 st step of mounting the object on a movable body movable in 1 st and 2 nd directions on a predetermined plane; and a 2 nd step of detecting a different number of marks from the position of the object in the 1 st direction by using a mark detection system having a detection region whose position is different in the 2 nd direction when the moving body is moved in the 1 st direction and a mark whose position is different in the 1 st direction on the object is detected.

Accordingly, it is possible to simultaneously detect marks at positions different from each other on the object using a required number of mark detection systems depending on the position of the moving body in the 1 st direction when the moving body is moved in the 1 st direction.

A 33 th aspect of the present invention is a 4 th exposure method of exposing an object with an energy beam, comprising: a step of mounting the object on a movable body which is movable in the 1 st and 2 nd directions in a predetermined plane and in which lattice portions in which lattices are periodically arranged are provided on a surface substantially parallel to the plane; and a step of measuring positional information of the movable body in the array direction by a reading head facing the lattice section, using a measuring device including an encoder having a plurality of reading heads whose positions are different in a direction intersecting the lattice array direction, at the time of detection operation of the mark by a mark detection system that detects the mark on the object.

Accordingly, when the mark detection operation on the object is performed, the encoder of the measuring device measures the positional information of the moving body in the grid arrangement direction of the grid section.

A 34 th aspect of the present invention is a 5 th exposure method for exposing an object with an energy beam via an optical system, comprising: a step of mounting the object on a movable body movable in the 1 st and 2 nd directions in a predetermined plane; and controlling an adjusting device that adjusts optical characteristics of the optical system based on a detection result of a part of the plurality of marks detected up to that point in the middle of the detection operation of the plurality of marks on the object.

In this way, the adjustment device is controlled to adjust the optical characteristics of the optical system based on the detection results of a part of the plurality of marks on the object detected so far during the detection operation of the plurality of marks on the object.

A 35 th aspect of the present invention is a 6 th exposure method for exposing an object with a pattern illuminated by an energy beam via an optical system, comprising: a 1 st step of mounting the object on a movable body movable in 1 st and 2 nd directions on a predetermined plane; and a 2 nd step of simultaneously performing at least a part of the operations of measuring the positional relationship between the projected position of the pattern and the detection center of a mark detection system for detecting a mark on the object and detecting the mark by the mark detection system.

A 36 th aspect of the present invention is a 7 th exposure method of exposing an object with an energy beam, comprising: a step of mounting the object on a movable body movable in the 1 st and 2 nd directions in a predetermined plane; and a 1 st state in which the movable body and another movable body different from the movable body approach each other at a predetermined distance or less and a 2 nd state in which the two movable bodies are separated from each other can be set; and switching the 1 st and 2 nd states between the detection operations of the mark by a mark detection system for detecting the mark on the object.

Accordingly, in the detection operation of the mark on the object by the mark detection system, the switching operation of the 1 st state in which the moving body approaches another moving body by a predetermined distance or less and the 2 nd state in which the moving bodies are separated is performed. This can improve the throughput compared to the case where the switching operation of the state is performed before or after the mark detection operation on the object.

A 37 th aspect of the present invention is a method for manufacturing a component, comprising: a step of exposing the object using the exposure method according to any one of claims 102 to 133; and

And developing the exposed object.

Drawings

FIG. 1 is a schematic configuration diagram showing an exposure apparatus according to an embodiment.

Fig. 2 is a plan view showing the stage device of fig. 1.

Fig. 3 is a plan view showing the arrangement of various measuring devices (an encoder, an alignment system, a multipoint AF system, a Z sensor, and the like) included in the exposure apparatus of fig. 1.

Fig. 4(a) is a plan view showing the wafer stage, and fig. 4(B) is a schematic side view showing a partial cross section of the wafer stage.

Fig. 5(a) is a plan view showing the measurement stage, and fig. 5(B) is a schematic side view showing a partial cross section of the measurement stage.

Fig. 6 is a perspective view showing the X-axis fixtures 80 and 81 in the vicinity of the + X-side end in fig. 2.

Fig. 7(a) to 7(D) are views for explaining the operation of the brake mechanism.

FIG. 8 is a block diagram showing a main configuration of a control system of an exposure apparatus according to an embodiment.

Fig. 9(a) and 9(B) are diagrams for explaining the position measurement of the wafer stage in the XY plane and the connection of the measurement values between the heads by the plurality of encoders each including the plurality of heads arranged in an array.

Fig. 10(a) is a diagram showing an encoder configuration example, and fig. 10(B) is a diagram showing a case where a laser beam LB having a cross-sectional shape extending long in the periodic direction of the grating RG is used as the detection light.

Fig. 11 is a diagram for explaining correction of the grating pitch and correction of the grating deformation of the scale by the exposure apparatus according to the embodiment.

Fig. 12(a) to 12(C) are views for explaining wafer alignment by the exposure apparatus according to one embodiment.

Fig. 13(a) to 13(C) are views for explaining simultaneous detection of a mark on a wafer by a plurality of alignment systems while changing the Z position of wafer table WTB (wafer W).

Fig. 14(a) and 14(B) are diagrams for explaining the baseline measurement operation of the first alignment system.

Fig. 15(a) and 15(B) are diagrams for explaining the baseline measurement operation of the second alignment system performed at the head of the batch.

Fig. 16 is a diagram for explaining a baseline inspection operation of the second alignment system performed for a replacement wafer.

Fig. 17(a) and 17(B) are diagrams for explaining the position adjustment operation of the second alignment system.

Fig. 18(a) to 18(C) are views for explaining focus matching by the exposure apparatus according to one embodiment.

Fig. 19(a) and 19(B) are views for explaining focus correction by the exposure apparatus according to one embodiment.

Fig. 20(a) and 20(B) are diagrams for explaining the AF inter-sensor offset correction performed by the exposure apparatus according to one embodiment.

Fig. 21(a) and 21(B) are views for explaining the correction of the movement of the conductive wire Z by the exposure apparatus according to the embodiment.

Fig. 22 is a diagram showing the states of the wafer stage and the measurement stage in a state where step-and-scan type exposure is performed on a wafer on the wafer stage.

Fig. 23 is a diagram showing the states of the wafer stage and the measurement stage at the stage when exposure of the wafer W to the wafer stage WST side has been completed.

Fig. 24 is a diagram showing a state of the wafer stage and the measurement stage after moving from a state in which the two stages are separated from each other to a state in which the two stages are just in contact with each other.

Fig. 25 is a diagram showing the states of the wafer stage and the measurement stage when the measurement stage is moved in the-Y direction and the wafer stage is moved to the unload position while maintaining the positional relationship between the wafer stage and the measurement stage in the Y-axis direction.

Fig. 26 is a diagram showing the state of the wafer stage and the measurement stage when the measurement stage reaches a position where Sec-BCHK (time interval) is to be performed.

Fig. 27 is a diagram showing the states of the wafer stage and the measurement stage when the wafer stage is moved from the unloading position to the loading position while the Sec-BCHK (time interval) is performed.

Fig. 28 is a diagram showing the states of the wafer stage and the measurement stage when the measurement stage moves to the optimum emergency stop standby position and the wafer is mounted on the wafer stage.

Fig. 29 is a diagram showing the states of the two stages when the wafer stage is moving to the position where the first half of the processing of Pri-BCHK is performed while the measurement stage is waiting at the optimum emergency stop standby position.

FIG. 30 is a schematic view of a system using alignment systems AL1, AL2₂、AL2₃And a diagram of states of the wafer stage and the measurement stage when the alignment marks attached to the three first alignment irradiation areas are simultaneously detected.

Fig. 31 is a diagram showing states of the wafer stage and the measurement stage when the first half of the focus correction process is performed.

FIG. 32 is a schematic view of a system using alignment systems AL1, AL2₁～AL2₄And a diagram of the states of the wafer stage and the measurement stage when the alignment marks attached to the five second alignment irradiation areas are simultaneously detected.

Fig. 33 is a diagram showing the states of the wafer stage and the measurement stage when at least one of the processing of the second half of Pri-BCHK and the processing of the second half of focus correction is performed.

FIG. 34 is a schematic view of a system using alignment systems AL1, AL2₁～AL2₄And a diagram of the states of the wafer stage and the measurement stage when the alignment marks attached to the five third alignment irradiation areas are simultaneously detected.

FIG. 35 is a schematic view of a system using alignment systems AL1, AL2₂、AL2₃And a diagram of the states of the wafer stage and the measurement stage when the alignment marks attached to the five second alignment irradiation areas are simultaneously detected.

Fig. 36 is a diagram showing states of the wafer stage and the measurement stage at the time of completion of the focus matching.

Fig. 37 is a flowchart for explaining an embodiment of the device manufacturing method.

FIG. 38 is a flow chart illustrating a particular embodiment of step 204 of FIG. 37.

Description of the reference numerals

5: a liquid supply device; 6: a liquid recovery device; 8: a local immersion liquid device; 10: an illumination system; 11: a reticle stage drive system; 12: a base; 14: a liquid immersion area; 15: moving the mirror; 16. 18Y: an axis interferometer; 17a, 17b, 19a, 19 b: a reflective surface; 20: a main control device; 28: a plate body; 28 a: a 1 st lyophobic area; 28 b: a 2 nd lyophobic area; 28b₁: part 1 area; 28b₂: a 2 nd partial region; 30: measuring a plate; 31A: a liquid supply tube; 31B: a liquid recovery pipe; 32: a mouth unit; 34A, 34B: a drive mechanism; 36: a frame body; 37. 38: a grating line; 39X₁、39X₂: an X scale; 39Y of₁、39Y₂: a Y scale; 40: a lens barrel; 41A, 41B: a plate-like member; 42: a mounting member; 43A, 43C: an interval detection sensor; 43B, 43D: a collision detection sensor; 44: a light receiving system; 45: an aerial image measuring device; 46: a CD rod; 47A, 47B: a shock absorber; 47A, 48B: a brake mechanism; 49A, 49B: a shutter; 50: a stage device; 51A, 51B: an opening; 52: a reference grating; 54: a support member; 56 ₁～56₄: an arm; 58₁～58₄: a vacuum pad; 60₁～60₄: a rotation driving mechanism; 62A to 62D: a reading head unit; 64: a Y read head; 64 a: an illumination system; 64 b: an optical system; 64 c: a light receiving system; 64y₁、64y₂: a Y read head; 66: an X reading head; 68: an adjustment device; 70A, 70C: a Y linear encoder; 70B, 70D: an X linear encoder; 70E, 70F: a Y-axis linear encoder; 72a to 72 d: a Z sensor; 74_1， ₁～74_2，6: a Z sensor; 76_1，1～76_2，6: a Z sensor; 78: a local air conditioning system; 80. 81: an X-axis fixing member; 82. 84, 83, 85: a Y-axis movable member; 86. 87: a Y-axis fixing member; 90 a: an illumination system; 90 b: a light receiving system; 91. 92: a stage body; 94: an illuminance unevenness sensor; 96: an aerial image measurer; 98: a wavefront aberration measuring device; 99: a sensor group; 100: an exposure device; 101: an opening and closing sensor; 104a, 104 d: a piston; 116: a reticle interferometer; 118: an interferometer system; 124: a stage drive system; 126. 130, 130: an X-axis interferometer; 142. 143: a fixing member; 144A, 145A: a light emitting section; 144B, 145B: a light receiving section; 191: a front end lens; AL 1: a first alignment system; AL2₁～AL2₄: a second alignment system; AS: irradiating the area; AX: an optical axis; CL, LL: a centerline; CT: an up-down moving pin; FM: a fiducial marker; IA: an exposure area; IAR: an illumination area; IBX1, IBX2, IBY1, IBY 2: a ranging beam; IL: light for illumination; l2a, L2 b: a lens; LB: a laser beam; LB ₁、LB₂: a light beam; LD: a semiconductor laser; and (3) LP: a loading position; and (Lq): a liquid; LH: a straight line; m: masking; MTB: a measuring table; MST: a measuring platform; o: a center of rotation; PBS: a polarizing beam splitter; PL: a projection optical system; PU (polyurethane): a projection unit; r: a reticle; r1a, R1b, R2a, R2 b: a mirror; RG: a reflection type diffraction grating; RST: a reticle stage; SL: measuring the slit pattern by space image; UP: an unloading position; w: a wafer; WP1a, WP1 b: a lambda/4 plate; WTB: a wafer stage; WST: a wafer carrier.

Detailed Description

An embodiment of the present invention will be described below with reference to fig. 1 to 36.

Fig. 1 schematically shows a configuration of an exposure apparatus 100 according to an embodiment. The exposure apparatus 100 is a scanning type exposure apparatus of a step-and-scan method, i.e., a so-called scanner. As described later, in the present embodiment, the projection optical system PL is provided, and hereinafter, a direction parallel to the optical axis AX of the projection optical system PL is referred to as a Z-axis direction, a direction in which the reticle and the wafer are relatively scanned in a plane orthogonal to the Z-axis direction is referred to as a Y-axis direction, a direction orthogonal to the Z-axis and the Y-axis is referred to as an X-axis direction, and directions of rotation (inclination) about the X-axis, the Y-axis, and the Z-axis are referred to as θ X, θ Y, and θ Z directions, respectively.

The exposure apparatus 100 includes: an illumination system 10; a reticle stage RST for holding a reticle R illuminated with exposure illumination light (hereinafter referred to as "illumination light" or "exposure light") IL from the illumination system 10; a projection unit PU including a projection optical system PL for projecting the illumination light IL emitted from the reticle R onto the wafer W; a stage device 50 having a wafer stage WST and a measurement stage MST; and a control system for the above apparatus. Wafer W is mounted on wafer stage WST.

The illumination system 10 includes a light source, an illumination optical system including an illuminance uniformizing optical system including an optical integrator and the like, a reticle blind and the like (none of which are shown), as disclosed in, for example, japanese patent application laid-open No. 2001-313250 (corresponding to U.S. patent application publication No. 2003/0025890). In the illumination system 10, a slit-shaped illumination region IAR on a reticle R defined by a reticle blind (mask system) is illuminated with illumination light (exposure light) IL at a substantially uniform illuminance. Here, as the illumination light IL, an ArF excimer laser (wavelength 193nm) is used as an example. As the optical integrator, for example, a fly eye lens, a rod integrator (internal reflection type integrator), a diffractive optical element, or the like can be used.

A reticle R having a circuit pattern or the like formed on its pattern surface (the lower surface in fig. 1) is fixed to the reticle stage RTS by, for example, vacuum suction. Reticle stage RST can be driven slightly in the XY plane by reticle stage driving system 11 (not shown in fig. 1, see fig. 8) including, for example, a linear motor or the like, and can be driven in the scanning direction (in the Y-axis direction in the left-right direction in the drawing of fig. 1) at a predetermined scanning speed.

Positional information (including rotation information in the θ z direction) of reticle stage RST within the moving plane is detected at any time, for example, with a resolution of about 0.5 to 1nm by reticle laser interferometer (hereinafter referred to as "reticle interferometer") 116 via moving mirror 15 (actually, a Y moving mirror (or retroreflector) having a reflecting surface orthogonal to the Y axis direction and an X moving mirror having a reflecting surface orthogonal to the X axis direction are provided). The measurement values of reticle interferometer 116 are transmitted to main control device 20 (not shown in fig. 1, see fig. 8), and main control device 20 calculates the position of reticle stage RST in the X-axis direction, the Y-axis direction, and the θ z direction from the measurement values of reticle interferometer 116, and controls reticle stage drive system 11 based on the calculation results, thereby controlling the position (and speed) of reticle stage RST. Instead of the movable mirror 15, a reflecting surface (corresponding to the reflecting surface of the movable mirror 15) may be formed by mirror-finishing an end surface of the reticle stage RST. The laser interferometer 116 may measure position information of the reticle stage RST in at least one of the Z-axis direction, the θ x direction, and the θ y direction.

Projection unit PU is disposed below reticle stage RST in fig. 1. The projection unit PU includes: a lens barrel 40; and a projection optical system PL having a plurality of optical elements held in a predetermined positional relationship in the lens barrel 40. As the projection optical system PL, for example, a refractive optical system composed of a plurality of lenses (lens elements) arranged along an optical axis AX parallel to the Z-axis direction is used. The projection optical system PL is, for example, telecentric on both sides and has a predetermined projection magnification (for example, 1/4 times, 1/5 times, 1/8 times, or the like). Therefore, when illumination area IAR is illuminated with illumination light IL from illumination system 10, a reduced circuit pattern image (a reduced partial circuit pattern image) of reticle R in illumination area IAR is formed in area (hereinafter also referred to as "exposure area") IA via projection optical system PL (projection unit PU) by illumination light IL passing through reticle R whose 1 st surface (object surface) of projection optical system PL and its pattern surface are arranged substantially in agreement; the area IA is conjugate to the illumination area IAR formed on the wafer W on the 2 nd surface (image surface) side, the surface of which is coated with a resist (photosensitive agent). Although not shown, projection unit PU is mounted on a barrel holder supported by three support columns via a vibration isolation mechanism, for example, projection unit PU may be suspended and supported on a main frame member, not shown, disposed above projection unit PU, a base member, etc., on which reticle stage RST is disposed, as disclosed in pamphlet of international publication No. 2006/038952.

In the exposure apparatus 100 of the present embodiment, since the exposure is performed by applying the liquid immersion method, the aperture diameter on the reticle side is also increased as the numerical aperture NA of the projection optical system PL is substantially increased. Therefore, it is difficult for a refractive optical system composed of only lenses to satisfy the Petzval Condition (Petzval Condition), and the projection optical system tends to be large-sized. To avoid the enlargement of the projection optical system, a catadi optical system (catadi optical system) including a mirror and a lens may be used. In addition, not only the photosensitive layer but also a protective film (top coat film) for protecting the wafer or the photosensitive layer, for example, may be formed on the wafer W.

In addition, in the exposure apparatus 100 of the present embodiment, in order to perform exposure by applying the liquid immersion method, the nozzle unit 32 constituting a part of the local liquid immersion device 8 is provided so as to surround and hold the periphery of the lower end portion of the lens barrel 40 holding the optical element, here, the lens (hereinafter, also referred to as "tip lens") 191, which constitutes the projection optical system PL on the most image plane side (wafer W side). In the present embodiment, as shown in fig. 1, the lower end surface of the nozzle unit 32 is set to be substantially flush with the lower end surface of the distal end lens 191. The nozzle unit 32 includes a supply port and a recovery port for the liquid Lq, a lower surface disposed opposite to the wafer W and provided with the recovery port, and a supply flow path and a recovery flow path connected to the liquid supply tube 31A and the liquid recovery tube 31B, respectively. As shown in fig. 3, the liquid supply tube 31A and the liquid recovery tube 31B are inclined at 45 ° with respect to the X-axis direction and the Y-axis direction in a plan view (viewed from above), and are arranged symmetrically with respect to a line LV in the Y-axis direction passing through the optical axis AX of the projection optical system PL.

The liquid supply pipe 31A is connected at one end thereof to the other end of a supply pipe (not shown in fig. 1, see fig. 8) of the liquid supply device 5, and the liquid recovery pipe 31B is connected at one end thereof to the other end of a recovery pipe (not shown in fig. 1, see fig. 8) of the liquid recovery device 6.

The liquid supply device 5 includes a liquid tank, a pressure pump, a temperature control device, and a valve for controlling supply and stop of liquid to the liquid supply pipe 31A. For example, a flow rate control valve capable of not only supplying and stopping a liquid but also adjusting a flow rate is preferably used as the valve. The temperature control device adjusts the temperature of the liquid in the liquid tank to the same level as the temperature in a processing chamber (not shown) in which the exposure apparatus is housed. Further, the exposure apparatus 100 does not need to be provided with all of a tank for supplying a liquid, a pressure pump, a temperature control device, a valve, and the like, and at least a part thereof may be replaced with a facility in a factory in which the exposure apparatus 100 is installed.

The liquid recovery device 6 includes a tank and a suction pump for liquid, and a valve for controlling recovery and stop of liquid through the liquid recovery tube 31B. The valve is preferably the same flow control valve as the valve of the liquid supply apparatus 5. Further, the exposure apparatus 100 does not need to be provided with all of a tank, a suction pump, a valve, and the like for recovering the liquid, and at least a part thereof may be replaced with a facility in a factory in which the exposure apparatus 100 is installed.

In the present embodiment, pure water (hereinafter, simply referred to as "water" unless otherwise specified) through which ArF excimer laser light (light having a wavelength of 193 nm) can pass is used as the liquid. Pure water has an advantage that it can be easily obtained in a large amount in a semiconductor manufacturing factory or the like and does not adversely affect a resist on a wafer, an optical lens, or the like.

The refractive index n of water to ArF excimer laser light is approximately 1.44. In this water, the wavelength of the illumination light IL is shortened to 193nm × 1/n, which is about 134 nm.

The liquid supply device 5 and the liquid recovery device 6 each have a controller, and each controller is controlled by a main control device 20 (see fig. 8). The controller of the liquid supply apparatus 5 opens the valve connected to the liquid supply pipe 31A at a predetermined opening degree in accordance with a command from the main controller 20, and supplies water between the front end lens 191 and the wafer W via the liquid supply pipe 31A, the supply flow path, and the supply port. At this time, the controller of the liquid recovery apparatus 6 opens the valve connected to the liquid recovery tube 31B at a predetermined opening degree in accordance with a command from the main controller 20, and recovers water from between the front end lens 191 and the wafer W into the liquid recovery apparatus 6 (liquid tank) through the recovery port, the recovery flow path, and the liquid recovery tube 31B. At this time, the main controller 20 gives a command to the controller of the liquid supply device 5 and the controller of the liquid recovery device 6 so that the amount of water supplied between the front end lens 191 and the wafer W is constantly equal to the amount of water recovered. Accordingly, a certain amount of liquid (water) Lq (see fig. 1) is held between the front end lens 191 and the wafer W. At this time, the liquid (water) Lq held between the front end lens 191 and the wafer W is replaced as needed.

As is clear from the above description, the local immersion device 8 of the present embodiment includes the nozzle unit 32, the liquid supply device 5, the liquid recovery device 6, the liquid supply tube 31A, the liquid recovery tube 31B, and the like. Further, a part of the local immersion unit 8, for example, at least the nozzle unit 32 may be suspended and supported by a main frame (including the lens barrel holder) for holding the projection unit PU, or may be provided on a frame member different from the main frame. Alternatively, when the projection unit PU is suspended and supported as described above, the projection unit PU and the nozzle unit 32 may be suspended and supported integrally, but in the present embodiment, the nozzle unit 32 is provided on a measurement frame suspended and supported independently of the projection unit PU. In this case, the projection unit PU may not be suspended and supported.

Even when measurement stage MST is positioned below projection unit PU, a space between measurement table MTB and front end lens 191, which will be described later, can be filled with water in the same manner as described above.

In the above description, as an example, each of the liquid supply tube (nozzle) and the liquid recovery tube (nozzle) is provided, but the present invention is not limited to this, and a configuration having a plurality of nozzles as disclosed in, for example, pamphlet of international publication No. 99/49504 may be adopted as long as the arrangement is possible in consideration of the relationship with the surrounding members. That is, the liquid may be supplied to a space between the optical member (tip lens) 191 forming the lowermost end of the projection optical system PL and the wafer W. For example, the exposure apparatus of the present embodiment can be applied to a liquid immersion mechanism disclosed in pamphlet of international publication No. 2004/053955, a liquid immersion mechanism disclosed in european patent publication No. 1420298, and the like.

Returning to fig. 1, stage device 50 includes: a wafer stage WST and a measurement stage MST disposed above base 12; an interferometer system 118 (see fig. 8) including Y-axis interferometers 16 and 18 for measuring positional information of the stages WST and MST; an encoder system described later for measuring positional information of wafer stage WST at the time of exposure or the like; and a stage drive system 124 (see fig. 8) that drives stages WST and MST.

Non-contact bearings (not shown), for example, vacuum preload type air static pressure bearings (hereinafter referred to as "air pads") are provided at a plurality of positions on the bottom surfaces of wafer stage WST and measurement stage MST, and wafer stage WST and measurement stage MST are supported on top of base 12 in a non-contact manner through a gap of about several μm by the static pressure of pressurized air ejected from the air pads toward the top surface of base 12. Further, stages WST and MST can be independently driven in two-dimensional directions of the Y-axis direction (the left-right direction in the paper surface of fig. 1) and the X-axis direction (the direction orthogonal to the paper surface of fig. 1) by stage driving system 124.

More specifically, as shown in the plan view of fig. 2, a pair of Y-axis fixing members 86 and 87 extending in the Y-axis direction are disposed on the ground on one side and the other side in the X-axis direction, respectively, with the base 12 interposed therebetween. The Y-axis fixtures 86 and 87 are constituted by, for example, magnetic pole units in which permanent magnet groups constituted by a plurality of sets of N-pole magnets and S-pole magnets alternately arranged at predetermined intervals in the Y-axis direction are built. The Y-axis anchors 86 and 87 are provided with two Y-axis movable members 82 and 84, and 83 and 85, respectively, which are engaged with each other in a non-contact manner. That is, the total of four Y-axis movable members 82, 84, 83, 85 are inserted into the inner space of the Y-axis fixture 86 or 87 having the U-shaped XZ cross section, and are supported by the corresponding Y-axis fixture 86 or 87 in a noncontact manner via an air cushion, not shown, for example, via a gap of several μm. Each of the Y-axis movers 82, 84, 83, 85 is constituted by, for example, an armature unit in which armature coils are arranged at a predetermined interval in the Y-axis direction. That is, in the present embodiment, the Y-axis linear motors of the moving coil type are respectively configured by the Y-axis movable elements 82 and 84 configured by the armature unit units and the Y-axis fixed element 86 configured by the magnetic pole unit. Similarly, the Y-axis linear motors of the moving coil type are constituted by the Y-axis movable members 83 and 85 and the Y-axis fixed member 87, respectively. Hereinafter, the four Y-axis linear motors are appropriately referred to as a Y-axis linear motor 82, a Y-axis linear motor 84, a Y-axis linear motor 83, and a Y-axis linear motor 85, using the same reference numerals as those of the movable members 82, 84, 83, and 85, respectively.

Of the four Y-axis linear motors, the movable members 82 and 83 of the two Y-axis linear motors 82 and 83 are fixed to one end and the other end in the longitudinal direction of the X-axis fixing member 80 extending in the X-axis direction, respectively. The movable members 84, 85 of the remaining two Y-axis linear motors 84, 85 are fixed to one end and the other end of the X-axis fixing member 81 extending in the X-axis direction. Accordingly, the X-axis mounts 80 and 81 are driven along the Y-axis by a pair of Y-axis linear motors 82, 83, 84, and 85, respectively.

Each of the X-axis anchors 80 and 81 is composed of, for example, an armature unit in which armature coils are arranged at predetermined intervals in the X-axis direction.

One X-axis fixing member 81 is provided in a state of being inserted into an unillustrated opening formed in stage main body 91 (constituting a part of wafer stage WST, not shown in fig. 2, see fig. 1). Inside the opening of the stage main body 91, for example, a magnetic pole unit including a permanent magnet group composed of a plurality of sets of N-pole magnets and S-pole magnets alternately arranged at predetermined intervals in the X-axis direction is provided. The magnetic pole unit and the X-axis fixing unit 81 constitute a moving magnet type X-axis linear motor for driving the stage main body 91 in the X-axis direction. Similarly, the other X-axis fixing member 80 is provided in a state of being inserted into an unillustrated opening formed in the stage main body 92 (constituting the measurement stage MST, not illustrated in fig. 2, see fig. 1). Inside the opening of the stage main body 92, a magnetic pole unit similar to that of the stage main body 91 on the wafer stage WST side) is provided. The magnetic pole unit and the X-axis fixing unit 80 constitute a moving magnet type X-axis linear motor for driving the measurement stage MST in the X-axis direction.

In the present embodiment, each of the linear motors constituting stage drive system 124 is controlled by main control device 20 shown in fig. 8. The linear motors are not limited to either of the moving magnet type and the moving coil type, and can be appropriately selected as needed.

Further, by slightly changing the thrust forces generated by the pair of Y-axis linear motors 84 and 85, respectively, the deflection (rotation in the direction of θ z) of wafer stage WST can be controlled. Further, by slightly changing the thrust forces generated by the pair of Y-axis linear motors 82 and 83, the deflection of the measurement stage MST can be controlled.

Wafer stage WST includes: the stage body 91; and a wafer table WTB mounted on stage main body 91 via a Z leveling mechanism (e.g., a voice coil motor, etc.), not shown, and capable of driving wafer table WTB in the Z-axis direction, the θ x direction, and the θ y direction slightly with respect to stage main body 91. In fig. 8, the linear motors described above are shown together with the Z leveling mechanism as a stage driving system 124.

The wafer table WTB is provided with a wafer holder (not shown) for holding the wafer W by vacuum suction or the like. Although the wafer holder may be formed integrally with wafer table WTB, in the present embodiment, the wafer holder and wafer table WTB are separately configured, and the wafer holder is fixed in the recess of wafer table WTB by, for example, vacuum suction. Further, a plate body (lyophobic plate) 28 having substantially the same height as the surface of the wafer mounted on the wafer holder, a rectangular outer shape (outline), and a circular opening slightly larger than the wafer holder (wafer mounting area) is formed in the center portion is provided on the upper surface of the wafer table WTB. The plate body 28 is made of a material having a low thermal expansion coefficient, such as glass or ceramic (trade name: Zerodur, Seidel), or Al ₂O₃Or TiC) and made of a fluorine resin material, polytetrafluoroethylene (teflon (registered trademark)), or the likeA fat material, an acrylic resin material, a silicone resin material, or the like. As shown in the plan view of wafer table WTB (wafer stage WST) in fig. 4 a, plate body 28 has a 1 st lyophobic area 28a having a rectangular outer shape (outline) for surrounding a circular opening, and a 2 nd lyophobic area 28b having a rectangular frame shape (ring shape) disposed around 1 st lyophobic area 28 a. For example, during the exposure operation, the 1 st lyophobic region 28a is formed with at least a part of the liquid immersion region 14 extending from the wafer surface, and the 2 nd lyophobic region 28b is formed with a scale for an encoder system to be described later. At least a part of the surface of the plate 28 may not be flush with the surface of the wafer, or may be different in height. The plate 28 may be a single plate, but in the present embodiment, the plate is a plurality of plates, and is configured by combining, for example, the 1 st and 2 nd lyophobic plates corresponding to the 1 st and 2 nd lyophobic regions 28a and 28b, respectively. In the present embodiment, since pure water is used as the liquid Lq as described above, the 1 st and 2 nd lyophobic regions 28a and 28b are also referred to as the 1 st and 2 nd lyophobic plates 28a and 28b hereinafter.

In this case, the exposure light IL hardly irradiates the outer 2 nd hydrophobic plate 28b, as opposed to the 1 st hydrophobic plate 28a which irradiates the inner side with the exposure light IL. In view of this, in the present embodiment, the 1 st hydrophobic region to which a hydrophobic coating film having sufficient resistance to the exposure light IL (in this case, light in the vacuum ultraviolet region) is applied is formed on the surface of the 1 st hydrophobic plate 28a, and the 2 nd hydrophobic region to which a hydrophobic coating film having less resistance to the exposure light IL than the 1 st hydrophobic region is applied is formed on the surface of the 2 nd hydrophobic plate 28 b. In general, since it is not easy to apply a hydrophobic coating film having sufficient resistance to the exposure light IL (in this case, light in the vacuum ultraviolet region) to the glass plate, it is more effective to separate the 1 st hydrophobic plate 28a and the 2 nd hydrophobic plate 28b around the 1 st hydrophobic plate into two parts as described above. Further, the present invention is not limited to this, and two kinds of hydrophobic coating films having different resistances to the exposure light IL may be applied to the upper surface of the same plate body to form the 1 st hydrophobic region and the 2 nd hydrophobic region. The kind of the hydrophobic coating film in the 1 st and 2 nd hydrophobic regions may be the same. Or, for example, only one hydrophobic region may be formed on the same plate body.

As is clear from fig. 4 a, a rectangular notch is formed in the center of the + Y-side end of the 1 st hydrophobic plate 28a in the X-axis direction, and the measurement plate 30 is embedded in a rectangular space (inside the notch) surrounded by the notch and the 2 nd hydrophobic plate 28 b. A reference mark FM is formed at the center in the longitudinal direction of the measurement plate 30 (on the center line LL of the wafer table WTB), and a pair of aerial image measurement slit patterns (slit-shaped measurement patterns) SL arranged symmetrically with respect to the center of the reference mark are formed on one side and the other side of the reference mark in the X-axis direction. For each aerial image measurement slit pattern SL, for example, an L-shaped slit pattern having sides extending in the Y-axis direction and the X-axis direction, two linear slit patterns extending in the X-axis direction and the Y-axis direction, or the like is used.

As shown in fig. 4B, L-shaped frame 36 housing an optical system (including an objective lens, a mirror, a relay lens, and the like) is attached so as to penetrate a part of the inside of stage body 91 from wafer table WTB, and so as to be partially embedded in the inside of wafer stage WST below each aerial image measuring slit pattern SL. Although not shown, a pair of frames 36 is provided corresponding to the pair of aerial image measurement slit patterns SL.

The optical system inside the housing 36 guides the illumination light IL transmitted through the aerial image measuring slit pattern SL along an L-shaped path and emits the illumination light IL in the-Y direction. For convenience of description, the optical system inside the housing 36 is described as the light transmission system 36 using the same reference numeral as that of the housing 36.

Furthermore, a plurality of grid lines are directly formed on the upper surface of the 2 nd hydrophobic plate 28b at predetermined pitches along the four sides thereof. More specifically, a Y scale 39Y is formed in each of the regions on one side and the other side (left and right sides in fig. 4 a) of the 2 nd hydrophobic plate 28b in the X axis direction₁、39Y₂The Y scale 39Y₁、39Y₂For example, a reflection type grating (for example, diffraction type grating) having a lattice line 38 whose longitudinal direction is the X-axis direction and whose periodic direction is the Y-axis direction is formed along a direction (Y-axis direction) parallel to the Y-axis at a predetermined pitchA grating).

Similarly, an X scale 39X is formed in each of the regions on one side and the other side (upper and lower sides in fig. 4 a) of the 2 nd hydrophobic plate 28b in the Y axis direction₁、39X₂The X scale 39X₁、39X₂For example, the grating is constituted by a reflection type grating (for example, a diffraction grating) in which lattice lines 37 having the Y-axis direction as the longitudinal direction are formed at a predetermined pitch in a direction (X-axis direction) parallel to the X-axis direction and the X-axis direction is a periodic direction. As each of the scales, for example, a scale having a reflection type diffraction grating RG (fig. 10 a) formed by a hologram or the like on the surface of the 2 nd hydrophobic plate 28b is used. In this case, a grating formed of narrow slits, grooves, or the like is formed as a scale at predetermined intervals (pitches). The type of the diffraction grating used for each scale is not limited, and the diffraction grating may be formed by mechanically forming grooves or the like, for example, by sintering interference fringes on a photosensitive resin. Each scale is formed by, for example, scribing the scale of the diffraction grating on a thin plate glass at a pitch of 138nm to 4 μm (for example, 1 μm pitch). These scales are covered with the aforementioned lyophobic film (hydrophobic film). In fig. 4(a), for convenience of illustration, the pitch of the grating is illustrated to be much larger than the actual pitch. This point is the same in other figures.

In this way, in the present embodiment, since the 2 nd hydrophobic plate 28b itself is configured as a scale, a glass plate having low thermal expansion is used as the 2 nd hydrophobic plate 28 b. However, the present invention is not limited to this, and a scale member made of a low thermal expansion glass plate on which a grating is formed may be fixed to the upper surface of wafer table WTB by, for example, a plate spring (or vacuum suction) so as to avoid local expansion and contraction, and in this case, a hydrophobic plate having the same hydrophobic coating film applied to the entire surface may be used instead of plate body 28. Alternatively, wafer table WTB may be formed of a material having a low thermal expansion coefficient, and in this case, the pair of Y scales and the pair of X scales may be formed directly on wafer table WTB.

the-Y end face and the-X end face of wafer table WTB are mirror-finished to form a reflection surface 17a and a reflection surface 17b shown in fig. 2, respectively. Y-axis interferometer 16 and X-axis interferometer 126 (X-axis interferometer 126 is not shown in fig. 1, see fig. 2) of interferometer system 118 (see fig. 8), respectively, project interferometer beams (ranging beams) onto reflection surfaces 17a and 17b, respectively, and receive the respective reflected lights to measure the displacement of the respective reflection surfaces from a reference position (generally, a fixed mirror is disposed on the side surface of projection unit PU, and the position is taken as a reference surface), that is, the positional information of wafer stage WST in the XY plane, and supply the measured values to main control device 120. In the present embodiment, a multi-axis interferometer having a plurality of optical axes is used as both the Y-axis interferometer 16 and the X-axis interferometer 126, and based on the measurement values of these Y-axis interferometer 16 and the X-axis interferometer 126, the main control device 120 can measure not only the X, Y position of the wafer table WTB but also rotation information in the θ X direction (that is, pitch), rotation information in the θ Y direction (that is, roll), and rotation information in the θ z direction (that is, yaw). However, in the present embodiment, position information (including rotation information in the θ z direction) of wafer stage WST (wafer table WTB) in the XY plane is mainly measured by an encoder system described later including the above-described Y scale, X scale, and the like, and the measurement values of interferometers 16 and 126 are used for, for example, correcting (correcting) long-term variations (for example, caused by changes in the scales with time) of the encoder system in an auxiliary manner. The Y-axis interferometer 16 is used for measuring the Y position of the wafer table WTB and the like near an unloading position and a loading position, which will be described later, for exchanging the wafer. For example, at least one of measurement information of interferometer system 118, that is, positional information in the five-degree-of-freedom direction (X-axis, Y-axis, θ X, θ Y, and θ z direction) is used for movement of wafer stage WST during the loading operation and the alignment operation and/or during the exposure operation and the unloading operation. At least a part of the interferometer system 118 (for example, an optical system or the like) may be provided on a main frame for holding the projection unit PU, or may be provided integrally with the projection unit PU suspended and supported as described above.

In the present embodiment, wafer stage WST includes a stage main body 91 that is movable in the XY plane, and a wafer table WTB that is mounted on stage main body 91 and is slightly driven in the Z-axis direction, θ x direction, and θ Z direction with respect to stage main body 91. Instead of the reflection surface 17b, a movable mirror formed of a flat mirror may be provided on the wafer table WTB. Although the positional information of wafer stage WST is measured using the reflection surface of the fixed mirror provided in projection unit PU as a reference surface, the position at which the reference surface is disposed is not limited to projection unit PU, and it is not always necessary to measure the positional information of wafer stage WST using the fixed mirror.

In the present embodiment, the positional information of wafer stage WST measured by interferometer system 118 is mainly used for a calibration operation of an encoder system (i.e., for calibration of a measurement value) and the like, not for an exposure operation or an alignment operation and the like described later, but the measurement information of interferometer system 118 (i.e., at least one of the positional information in the five-degree-of-freedom direction) may be used for, for example, an exposure operation and/or an alignment operation and the like. In the present embodiment, the encoder system measures positional information of wafer stage WST in three degrees of freedom, that is, in the X-axis, Y-axis, and θ z-direction. Therefore, in the case of performing an exposure operation or the like, the positional information of interferometer system 118 may be obtained by using only the positional information in the direction different from the measurement direction (X-axis, Y-axis, and θ z-direction) of the positional information of encoder system with respect to wafer stage WST, for example, the positional information in the θ X-direction and/or the θ Y-direction, or by adding the positional information in the same direction as the measurement direction of the encoder system (i.e., at least one of the X-axis, Y-axis, and θ z-direction) to the positional information in the different direction. Interferometer system 118 may measure positional information of wafer stage WST in the Z-axis direction. In this case, the position information in the Z-axis direction may be used for the exposure operation.

The measurement stage MST includes the stage main body 92 and a measurement table MTB mounted on the stage main body 92. The measurement table MTB is also mounted on the stage body 92 via a Z leveling mechanism not shown. However, the present invention is not limited to this, and a measurement stage MST having a so-called coarse fine movement structure in which measurement table MTB can be finely moved in the X-axis direction, the Y-axis direction, and the θ z direction with respect to stage main body 92 may be adopted, or stage main body 92 including measurement table MTB may be configured to be drivable in the six-degree-of-freedom direction by fixing measurement stage MST to stage main body 92.

Various measuring members are provided on measuring table MTB (and stage main body 92). As the measuring means, for example, as shown in fig. 2 and 5 a, an uneven illuminance sensor 94 having a pinhole-shaped light receiving unit for receiving illumination light IL on an image plane of the projection optical system PL, an aerial image measuring instrument 96 for measuring an aerial image (projection image) of a pattern projected by the projection optical system PL, a Shack-Hartman type wavefront aberration measuring instrument 98 disclosed in, for example, international publication No. 03/065428 pamphlet, and the like are used. As the wavefront aberration sensor 98, for example, one disclosed in international publication No. 99/60361 pamphlet (corresponding to european patent No. 1,079,223) can be used.

As the uneven illuminance sensor 94, for example, a structure similar to that disclosed in japanese patent application laid-open No. 57-117238 (corresponding to U.S. Pat. No. 4,465,368) or the like can be used. The aerial image measuring instrument 96 can be constructed in the same manner as disclosed in, for example, japanese patent application laid-open No. 2002-14005 (corresponding to U.S. patent application publication No. 2002/0041377). In the present embodiment, three measuring members (94, 96, 98) are provided on measurement stage MST, but the type, number, and the like of the measuring members are not limited to these. As the measuring means, for example, a transmittance measuring instrument for measuring the transmittance of the projection optical system PL, a measuring instrument for observing the local immersion device 8, for example, the nozzle unit 32 (or the distal end lens 191), or the like can be used. Further, members different from the measuring members, for example, cleaning members for cleaning the nozzle unit 32, the tip lens 191, and the like, may be mounted on the measurement stage MST.

In the present embodiment, as can be seen from fig. 5 a, the sensors with high frequency of use, uneven illuminance sensor 94, aerial image measuring instrument 96, and the like are disposed on center line CL (Y axis passing through the center) of measurement stage MST. Therefore, in the present embodiment, the measurement using these sensors is performed not by moving measurement stage MST in the X-axis direction but only by moving it in the Y-axis direction.

In addition to the above-described sensors, an illuminance monitor (having a light receiving unit of a predetermined area for receiving the illumination light IL on the image plane of the projection optical system PL) disclosed in, for example, japanese patent application laid-open No. 11-16816 (corresponding to U.S. patent application laid-open No. 2002/0061469) may be used, and the illuminance monitor is preferably disposed on the center line.

In the present embodiment, in response to the immersion exposure performed to expose the wafer W with the exposure light (illumination light) IL through the projection optical system PL and the liquid (water) Lq, the illumination light IL is received through the projection optical system PL and water in the uneven illuminance sensor 94 (and the illuminance monitor), the aerial image measuring device 96, and the wavefront aberration sensor 98 used for measurement using the illumination light IL. Each sensor may be mounted on measurement table MTB (and stage main body 92) only in part of the optical system and the like, or the entire sensor may be disposed on measurement table MTB (and stage main body 92), for example.

As shown in fig. 5(B), frame-shaped mounting member 42 is fixed to a-Y-side end surface of stage main body 92 of measurement stage MST. Further, a pair of light receiving systems 44 are fixed to the-Y side end surface of the stage body 92 so as to be disposed opposite to the pair of light transmitting systems 36 in the vicinity of the center position in the X axis direction in the opening of the mounting member 42. Each light receiving system 44 is constituted by an optical system such as a relay lens, a light receiving element (for example, a photomultiplier tube), and a housing that houses these components. As is clear from fig. 4(B) and 5(B) and the description up to now, in the present embodiment, in a state (including a contact state) in which wafer stage WST and measurement stage MST are within a predetermined distance in the Y-axis direction, illumination light IL transmitted through each aerial image measurement slit pattern SL of measurement plate 30 is guided by each light transmitting system 36 and received by the light receiving elements of each light receiving system 44. That is, the measurement plate 30, the light transmitting system 36, and the light receiving system 44 constitute an aerial image measuring apparatus 45 (see fig. 8) similar to that disclosed in the aforementioned japanese patent application laid-open No. 2002-14005 (corresponding to the specification of U.S. patent application publication No. 2002/0041377) and the like.

A reference bar (hereinafter, simply referred to as "CD bar") as a reference member made of a bar-shaped member having a rectangular cross section extends from the mounting member 42. The CD bar 46 is dynamically supported on the measurement stage MST by a fully dynamic frame structure.

Since the CD bar 46 is an original (measurement standard), an optical glass ceramic having a low thermal expansion coefficient, for example, Zerodur (trade name) of seidel corporation, or the like is used as a material. The flatness of the upper surface (surface) of the CD bar 46 is set high to the same degree as that of a so-called reference plane plate. As shown in fig. 5 a, reference lattices (e.g., diffraction gratings) 52 each having a periodic direction in the Y-axis direction are formed in the vicinity of one end and the other end in the longitudinal direction of the CD bar 46. The pair of reference lattices 52 are formed symmetrically with a predetermined distance (L) therebetween at the center in the X-axis direction of the CD bar 46, i.e., at a distance from the center line CL.

Further, a plurality of reference marks M are formed on the upper surface of the CD bar 46 in the arrangement shown in fig. 5 (a). The plurality of reference marks M are arranged in three rows in the Y-axis direction at the same pitch, and the rows are arranged to be offset from each other by a predetermined distance in the X-axis direction. Each reference mark M is, for example, a two-dimensional mark having a size detectable by a first alignment system and a second alignment system described later. The shape (configuration) of the fiducial marks M may be different from that of the fiducial marks FM, but in the present embodiment, the fiducial marks M are configured in the same manner as the fiducial marks FM, and are also configured in the same manner as the alignment marks of the wafer W. In the present embodiment, the surface of the CD bar 46 and the surface of the measuring table MTB (which may include the measuring member) are each covered with a liquid repellent film (water repellent film).

Reflection surfaces 19a and 19b (see fig. 2 and 5 a) similar to wafer table WTB are also formed on the + Y end surface and the-X end surface of measurement table MTB. Y-axis interferometer 18 and X-axis interferometer 130 (X-axis interferometer 130 is not shown in fig. 1, see fig. 2) of interferometer system 118 (see fig. 8), as shown in fig. 2, project interferometer beams (ranging beams) onto reflection surfaces 19a and 19b, respectively, and receive the respective reflected lights to measure the displacement of the reflection surfaces from the reference position, that is, the positional information of measurement stage MST (including, for example, positional information in the X-axis and Y-axis directions and rotational information in the θ z direction), and supply the measured values to main controller 120.

As shown in fig. 2, brake mechanisms 48A and 48B are provided in the X-axis mount 81 and the X-axis mount 80. As shown in fig. 6, which is a perspective view showing the vicinity of the + X-side end of the X-axis mounts 80 and 81, the stopper mechanism 48A includes: a damper 47A provided in the X-axis mount 81 and including a buffer device such as an oil damper; and a shutter 49A provided at a position opposite to the damper 47A of the X-axis mount 80 (+ Y-side end surface of the X-side end). An opening 51A is formed in the X-axis mount 80 at a position facing the damper 47A.

As shown in fig. 6, the shutter 49A is provided on the-Y side of the opening 51A formed in the X-axis mount 80, and can be driven in the direction of an arrow A, A' (Z-axis direction) by a driving mechanism 34A including an air cylinder or the like. Accordingly, the opening 51A can be opened or closed by the shutter 49A. The open/close state of the shutter 49A is detected by a switch sensor (not shown in fig. 6, see fig. 8)101 provided in the vicinity of the shutter 49A, and the detection result is sent to the main control device 20.

The brake mechanism 48B is also configured similarly to the brake mechanism 48A. As shown in fig. 2, the brake mechanism 48B includes: a damper 47B provided in the vicinity of the-X end of the X-axis mount 81, and a shutter 49B provided at a position of the X-axis mount 80 facing the damper 47B. Further, an opening 51B is formed in the X-axis mount 80 on the + Y side portion of the shutter 49B.

Here, the operation of the brake mechanisms 48A and 48B will be described with reference to the brake mechanism 48A as a representative example, with reference to fig. 7(a) to 7 (D).

As shown in fig. 7(a), even when the shutter 48A is in a state of closing the opening 51A and the X-axis mount 81 and the X-axis mount 80 approach each other as shown in fig. 7(B), the X-axis mounts 80 and 81 cannot approach each other by the contact (abutment) of the damper 47A and the shutter 49A. At this time, as shown in fig. 7B, when reading head 104d fixed to the front end of piston 104a of damper 47A moves to the most-Y side (that is, when the unillustrated spring of damper 47A is contracted to the shortest length and the entire length thereof is the shortest), wafer table WTB and measurement table MTB are also configured so as not to contact each other.

On the other hand, as shown in fig. 7(C), when the shutter 49A is driven to be lowered via the drive mechanism 34A, the opening 51A is opened. At this time, when the X-axis fixtures 81 and 80 approach each other, as shown in fig. 7(D), at least a part of the distal end portion of the piston 104A of the damper 74A can be inserted into the opening 51A, and the X-axis fixtures 80 and 81 can be brought closer to each other than the state shown in fig. 7 (B). In a state where X-axis fixtures 81 and 80 are closest to each other, wafer table WTB and measurement table MTB (CD bar 46) can be brought into contact with each other (or brought close to each other by a distance of about 300 μm) (see fig. 14B and the like).

As shown in fig. 7D, the depth of the opening 51A may be set so that a gap is formed between the damper 47A and the terminal end portion (corresponding to the bottom portion) of the opening 51A even in a state where the X-axis fixtures 81 and 80 are closest to each other, or so that the read head 104D of the piston 104a of the damper 47A contacts the terminal end portion. When the X-axis mounts 81 and 80 are relatively moved in the X-axis direction, the opening width may be set in advance so that the damper 47A does not contact the wall of the opening 51A according to the amount of the relative movement.

In the present embodiment, a pair of brake mechanisms 48A and 48B are provided on X-axis fixture 81 and X-axis fixture 80, but only one of brake mechanisms 48A and 48B may be provided, or the same brake mechanisms as those described above may be provided on wafer stage WST and measurement stage MST.

Returning to fig. 2, a gap detection sensor 43A and an impact detection sensor 43B are provided at the + X end of the X-axis mount 80, and a long and narrow plate-like member 41A extending in the Y-axis direction is provided at the + Y side of the + X end of the X-axis mount 81. As shown in fig. 2, a distance detection sensor 43C and an impact detection sensor 43D are provided at the-X end of the X-axis fixing member 80, and a long and narrow plate-like member 41B extending in the Y-axis direction is provided at the + Y side of the-X end of the X-axis fixing member 81.

The interval detection sensor 43A is composed of, for example, a transmission type photosensor (for example, a transmission type photosensor of LED-PTr), and includes, as shown in fig. 6, a U-shaped fixing member 142, and a light emitting portion 144A and a light receiving portion 144B provided on a pair of opposing surfaces of the fixing member 142. When the X-axis mount 80 and the X-axis mount 81 come closer to each other from the state shown in fig. 6 by the gap detection sensor 43A, the plate-like member 41A enters between the light receiving section 144B and the light emitting section 144A, and the lower half of the plate-like member 41A shields the light from the light emitting section 144A, so that the light received by the light receiving section 144B gradually decreases, and the output current thereof gradually decreases. Therefore, the main controller 20 detects the output current to detect that the distance between the X-axis fixtures 80 and 81 is equal to or less than the predetermined distance.

As shown in fig. 6, the collision detection sensor 43B includes a U-shaped fixing member 143, and a light emitting portion 145A and a light receiving portion 145B provided on a pair of facing surfaces of the fixing member 143. At this time, as shown in fig. 6, the light emitting portion 145A is arranged at a position slightly higher than the light emitting portion 144A of the interval detection sensor 43A, and correspondingly, the light receiving portion 145B is arranged at a position slightly higher than the light receiving portion 144B of the interval detection sensor 43A.

According to the impact detection sensor 43B, at a stage when the X-axis fixtures 81 and 80 are closer to each other and the wafer table WTB is brought into contact with the CD bar 46 (measurement table MTB) (or at a stage when the X-axis fixtures are closer to each other, the upper half of the plate-shaped member 41A is positioned between the light emitting portion 145A and the light receiving portion 145B, and therefore, the light from the light emitting portion 145A is not incident on the light receiving portion 145B. Therefore, the main control device 20 detects that the two systems are in contact with each other (or close to a distance of about 300 μm) by detecting that the output current from the light receiving part 145B is zero.

The interval detection sensor 43C and the collision detection sensor 43D provided in the vicinity of the-X end of the X-axis fixing member 80 have the same configurations as those of the interval detection sensor 43A and the collision detection sensor 43B described above, and the plate-shaped member 41B has the same configuration as that of the plate-shaped member 41A described above.

Although the exposure apparatus 100 of the present embodiment is omitted in fig. 1 in order to avoid an excessively complicated drawing, in actuality, as shown in fig. 3, a first alignment system AL1 is arranged, and this first alignment system AL1 has a detection center at a position spaced apart by a predetermined distance from the optical axis to the-Y side on a straight line LV passing through the center of the projection unit PU (coinciding with the optical axis AX of the projection optical system PL, and also coinciding with the center of the exposure area IA in the present embodiment) and parallel to the Y axis. The first alignment system AL1 is fixed to the lower surface of a main frame, not shown, via a support member 54. Second alignment systems AL2, the detection centers of which are arranged substantially symmetrically with respect to the straight line LV are provided on one side and the other side in the X-axis direction of the first alignment system AL1₁、AL2₂And AL2₃、AL2₄. Namely, five alignment systems AL1, AL2₁～AL2₄The detection centers of (2) are arranged at different positions in the X-axis direction, that is, in the X-axis direction.

Each second alignment system AL2_n(n-1-4), an alignment system AL2 as representatively shown₄In this way, the arm 56 is fixed to the arm which can rotate in the clockwise and counterclockwise directions in fig. 3 by a predetermined angle range around the rotation center O_n(n is 1 to 4) leading ends (turning ends). In the present embodiment, each second alignment system AL2 _nIs fixed to the arm 56 (for example, an optical system including at least a light guide for guiding light generated by an object mark in the detection area to a light receiving element) and irradiates the detection area with alignment light_nThe remaining part is disposed on a main frame for holding the projection unit PU. Second alignment System AL2₁、AL2₂、AL2₃、AL2₄The X positions are adjusted by rotating around the rotation centers O, respectively. Namely, the second alignment system AL2₁、AL2₂、AL2₃、AL2₄The detection area (or the detection center) of (a) can be independently moved in the X-axis direction. Due to the fact thatThe first and second alignment systems AL1 and AL2₁、AL2₂、AL2₃、AL2₄The relative position of the detection area in the X-axis direction can be adjusted. In addition, in the present embodiment, the second alignment system AL2 is adjusted by the rotation of the arm₁、AL2₂、AL2₃、AL2₄But not limited thereto, a second alignment system AL2 may be provided₁、AL2₂、AL2₃、AL2₄And a driving mechanism for driving the X-axis direction in a reciprocating manner. Additionally, a second alignment system AL2 may be provided₁、AL2₂、AL2₃、AL2₄Not only in the X-axis direction but also in the Y-axis direction. In addition, due to the second alignment systems AL2_nBy a portion of the arm 56_nSo that the measurement fixed to the arm 56 can be performed by a sensor not shown, such as an interferometer or an encoder_nA part of the location information. This sensor may measure only the second alignment system AL2 _nThe position information in the X-axis direction can be measured in other directions such as the Y-axis direction and/or the rotational direction (including at least one of the θ X and θ Y directions).

At each arm 56_nOn the upper surface, a vacuum pad 58 composed of a differential exhaust type air bearing is provided_n(n is 1 to 4). In addition, the arm 56_nFor example by means of a rotary drive mechanism comprising a motor or the like_n(n is 1 to 4, not shown in fig. 3, see fig. 8), and is rotatable in accordance with an instruction from the main control device 20. Main control device 20 is on arm 56_nAfter the rotation adjustment, the vacuum pads 58 are adjusted_nAct to move each arm 56_nIs fixed by suction to a main frame, not shown. Thus, each arm 56 can be maintained_nThe first alignment system AL1 and the 4 second alignment systems AL2 are maintained₁～AL2₄A desired positional relationship. In addition, the specific adjustment of the rotation of each arm, i.e. the 4 second alignment systems AL2₁～AL2₄The method of adjustment of the relative position with respect to the first alignment system AL1 remains to be described later.

In addition, the arms 56 with the main frame_nThe facing portion may be made of a magnetic material, and an electromagnet may be used instead of the vacuum pad 58.

The first alignment system AL1 and the 4 second alignment systems AL2 of the present embodiment₁～AL2₄For example, a Field Image Alignment (FIA) system of an Image processing system may be used, which irradiates a target mark with a wide-band detection beam that does not expose a resist on a wafer, and captures an Image of the target mark imaged on a light receiving surface by reflected light from the target mark and an Image of a pointer (pointer pattern on a pointer plate provided in each Alignment system), not shown, with an imaging device (CCD (charge coupled device) or the like) and outputs the captured signals. From the first alignment system AL1 and 4 second alignment systems AL2 ₁～AL2₄The respective imaging signals are supplied to the main controller 20 in fig. 8.

Note that the alignment systems are not limited to the FIA system, and it is needless to say that an alignment sensor capable of detecting scattered light or diffracted light generated from a target mark by irradiating the target mark with coherent detection light or an alignment sensor capable of detecting two diffracted lights (for example, diffracted light of the same order or diffracted light in the same direction) generated from the target mark by interfering with each other may be used alone or in an appropriate combination. In the present embodiment, five alignment systems AL1 and AL2 are provided₁～AL2₄However, the number is not limited to five, and two or more and four or less, or six or more, or even numbers other than odd numbers may be used. Furthermore, five alignment systems AL1, AL2₁～AL2₄The projection unit PU is fixed to the lower surface of the main frame for holding the projection unit PU via the support member 54, but the present invention is not limited thereto, and may be provided to the measurement frame.

In the exposure apparatus 100 of the present embodiment, as shown in fig. 3, four head units 62A to 62D of an encoder system are arranged so as to surround the periphery of the nozzle unit 32 from four directions. Although these head units 62A to 62D are omitted in fig. 3 and the like in order to avoid an excessively complicated drawing, they are actually fixed in a suspended state to a main frame that holds the projection unit PU via a support member. For example, when the projection unit PU is suspended, the head units 62A to 62D may be suspended and supported integrally with the projection unit PU or may be provided on the measurement frame.

The head units 62A and 62C are arranged on the + X side and the-X side of the projection unit PU with the X-axis direction as the longitudinal direction and at substantially the same distance from the optical axis AX with respect to the optical axis AX of the projection optical system PL. The head units 62B and 62D are disposed on the + Y side and the-Y side of the projection unit PU, respectively, with the Y-axis direction being the longitudinal direction and at substantially the same distance from the optical axis AX with respect to the optical axis AX of the projection optical system PL.

As shown in fig. 3, the head units 62A and 62C include a plurality of (six in this case) Y heads 64 arranged at predetermined intervals on a straight line LH passing through the optical axis AX of the projection optical system PL and parallel to the X axis. The head unit 62A is configured to use the Y scale 39Y₁Y linear encoder (hereinafter, referred to as "Y encoder" or "encoder" as appropriate) 70A (see fig. 8) for measuring the position (Y position) of wafer stage WST (wafer table WTB) in the Y axis direction for a plurality of eyes (here, six eyes). Similarly, the head unit 62C is configured to use the Y scale 39Y₂To measure the Y position of wafer stage WST (wafer table WTB), and a multi-eye (here, six-eye) Y encoder 70C (see fig. 8). Here, the interval between adjacent Y heads 64 (i.e., measuring beams) of the head units 62A and 62C is set to be larger than the Y scale 39Y ₁、39Y₂The width in the X-axis direction (more precisely, the length of the lattice line 38) is narrow. Further, the Y head 64 positioned innermost in the plurality of Y heads 64 included in each of the head units 62A and 62C is fixed to the lower end portion of the barrel 40 of the projection optical system PL (more precisely, the lateral side of the nozzle unit 32 surrounding the tip lens 191) so as to be disposed as far as possible on the optical axis of the projection optical system PL.

As shown in fig. 3, the head unit 62B includes a plurality of (here, seven) X-ray readings arranged on the straight line LV at predetermined intervalsA head 66. The head unit 62D includes a plurality of X heads 66 (here, eleven (however, three lines overlapping with the first alignment system AL1 in eleven in fig. 3 are not shown)) arranged on the straight line LV at predetermined intervals. The head unit 62B is configured to use the X scale 39X₁X linear encoder (hereinafter, referred to as "X encoder" or "encoder" as appropriate) 70B for measuring the position (X position) of wafer stage WST (wafer table WTB) in the X-axis direction for a plurality of eyes (here, seven eyes) (see fig. 8). The head unit 62D is configured to use the X scale 39X₂X encoder 70D (see fig. 8) for measuring a plurality of eyes (here, eleven eyes) of X position of wafer stage WST (wafer table WTB). In the present embodiment, for example, two of the eleven X heads 66 included in the head unit 62D may simultaneously face the X scale 39X during alignment or the like described below ₁X scale 39X₂. At this time, the X scale 39X is passed₁An X linear encoder 70B is formed with the X read head 66 facing thereto, and passes through the X scale 39X₂The X linear encoder 70D is configured with the X read head 66 facing thereto.

Here, a portion of the eleven X read heads 66, here three, are mounted below the support member 54 of the first alignment system AL 1. The interval between adjacent X heads 66 (measuring beams) provided in the head units 62B and 62D is set to be larger than the X scale 39X₁、39X₂The width in the Y-axis direction (more precisely, the length of the lattice line 37) is narrow. Further, the X read head 66 positioned innermost among the plurality of X read heads 66 provided in each of the head units 62B and 62D is fixed to the lower end portion of the lens barrel 40 of the projection optical system PL (more precisely, the lateral side of the nozzle unit 32 surrounding the tip lens 191) so as to be disposed as far as possible on the optical axis of the projection optical system PL.

Furthermore, in a second alignment system AL2₁Of the-X side, second alignment system AL2₄Is provided with a Y-read head 64Y which is arranged on a straight line (passing through the detection center of the first alignment system AL 1) parallel to the X-axis and has the detection points thereof arranged substantially symmetrically with respect to the detection center₁、64y₂. Y read head 64Y ₁、64y₂Is set to be substantially equal to the distance L. Y read head 64Y₁、64y₂In the state shown in fig. 3 where the center of the wafer W on the wafer stage WST is positioned on the straight line LV, the Y scale 39Y is provided₂、39Y₁Are opposite. The Y scale 39Y is used for alignment operation described later₂、39Y₁Respectively with the Y read head 64Y₁、64y₂Arranged oppositely, and the Y read head 64Y₁、64y₂(i.e., by these Y read heads 64Y₁、64y₂Y encoders 70C and 70A) configured to measure the Y position (and θ z rotation) of wafer stage WST.

In the present embodiment, when the baseline measurement of the second alignment system to be described later is performed, the pair of reference grids 52 of the CD bar 46 and the Y head 64Y₁、64y₂Are respectively opposite to each other and pass through the Y read head 64Y₁、64y₂The Y position of the CD bar 46 is measured for each of the reference lattices 52 facing each other 52. Hereinafter, the reference grid 52 is passed through the Y head 64Y facing each other₁、64y₂The encoders thus constructed are referred to as Y-axis linear encoders 70E and 70F (see fig. 8).

The measurement values of the six linear encoders 70A to 70E are supplied to main controller 20, and main controller 20 controls the position of wafer table WTB in the XY plane based on the measurement values of linear encoders 70A to 70D, and controls the rotation of CD lever 46 in the θ z direction based on the measurement values of encoders 70E and 70F.

As shown in fig. 3, the exposure apparatus 100 according to the present embodiment is provided with a multipoint focus position detection system of an oblique incidence system (hereinafter, simply referred to as "multipoint AF system") similar to that disclosed in, for example, japanese patent application laid-open No. 6-283403 (corresponding to U.S. Pat. No. 5,448,332) and the like, which is configured by an irradiation system 90a and a light receiving system 90b (see fig. 8). In the present embodiment, as an example, the irradiation system 90a is disposed on the-Y side of the-X end of the head unit 62C, and the light receiving system 90b is disposed on the-Y side of the + X end of the head unit 62A in a state opposed thereto.

A plurality of detection points of the multi-point AF systems (90a, 90b) are arranged at a predetermined interval in the X-axis direction on a detection surface. In the present embodiment, for example, the detection points are arranged in a matrix of M rows and M columns (M is the total number of detection points) or two rows and N columns (N is 1/2 of the total number of detection points). Fig. 3 does not individually show a plurality of detection points to which the detection beams are irradiated, and shows an elongated detection area AF extending in the X-axis direction between the irradiation system 90a and the light receiving system 90 b. Since the length of the detection area AF in the X axis direction is set to be the same as the diameter of the wafer W, the substantially entire Z axis direction position information (surface position information) of the wafer W can be measured by scanning the wafer W only once in the Y axis direction. In addition, since the detection area AF is disposed in the Y-axis direction between the liquid immersion area 14 (exposure area IA) and the alignment systems (AL1, AL 2) ₁、AL2₂、AL2₃、AL2₄) The detection operation can be performed by the multi-spot AF system and the alignment system at the same time. The multipoint AF system may be provided in a main frame or the like for holding the projection unit PU, but in the present embodiment, it is provided in the measurement frame.

The plurality of detection points are arranged in 1 row, M columns, or 2 rows, N columns, but the number of rows and/or columns is not limited thereto. However, when the number of rows is 2 or more, it is preferable that the positions of the detection points in the X-axis direction are also different between the rows. Further, the plurality of detection points are arranged along the X-axis direction, but the present invention is not limited to this, and for example, the plurality of detection points may be arranged along a direction intersecting both the X-axis and the Y-axis. That is, the plurality of detection points may be different in position at least in the X-axis direction. In the present embodiment, the detection beams are irradiated to the plurality of detection points, but the detection beams may be irradiated to the entire detection area AF, for example. The length of the detection area AF in the X-axis direction may not be the same as the diameter of the wafer W.

The exposure apparatus 100 of the present embodiment is provided with a pair of Z position measuring surface position sensors (hereinafter, simply referred to as "Z sensors") 72a, 72b, 72c, and 72d, respectively, in a symmetrical arrangement with respect to the straight line LV, in the vicinity of detection points located at both ends, that is, in the vicinity of both ends of the detection area AF, among the plurality of detection points of the multipoint AF system. These Z sensors 72a to 72d are fixed to the lower surface of a main frame, not shown. Z sensors 72a to 72d irradiate light onto wafer table WTB using, for example, an optical displacement sensor (CD pickup sensor) configured by an optical pickup used in a CD drive or the like, receive the reflected light, and measure positional information of the surface of wafer table WTB in the Z-axis direction orthogonal to the XY plane at the irradiation point of the light. The Z sensors 72a to 72d may be provided on the measurement frame.

The head unit 62C includes a plurality of (six, in total, twelve) Z sensors 74 located on one side and the other side with respect to a straight line LH in the X-axis direction connecting the plurality of Y heads 64, and arranged at predetermined intervals along two straight lines parallel to the straight line LH_i，j(i 1, 2, j 1, 2.., 6). At this time, the paired Z sensors 74_1， _jZ sensor 74_2，jIs arranged symmetrically with respect to the straight line LH. Further, a plurality of pairs (here, six pairs) of Z sensors 74_1，j、74_2，jAnd a plurality of Y read heads 64 are alternately arranged in the X-axis direction. Each Z sensor 74_i，jFor example, a CD pickup type sensor similar to the Z sensors 72a to 72d is used.

Here, each pair of Z sensors 74 located at positions symmetrical with respect to the straight line LH_1，j、74_2，jThe interval of (b) is set to be the same as the interval of the Z sensors 74c and 74 d. In addition, a pair of Z sensors 74_1，4、74_2，4On the same straight line parallel to the Y-axis direction as the Z sensors 72a, 72 b.

The head unit 62A includes the plurality of Z sensors 74 with respect to the straight line LV_i，jA plurality of, here 12, Z sensors 76 arranged symmetrically_p，q(p 1, 2, q 1, 2, 6). Each Z sensor 76_p，qFor example, a CD pickup type sensor similar to the Z sensors 72a to 72d is used. In addition, a pair of Z sensors 76 _1，3，76_2，3On the same line in the Y-axis direction as the Z sensors 72a, 72 b.

Note that, in fig. 3, measurement stage MST is not shown, and a liquid immersion area formed by water Lq held between measurement stage MST and tip lens 191 is denoted by reference numeral 14. In addition, in fig. 3, reference numeral 78 shows a local air conditioning system for sending the dry air whose temperature is adjusted to a prescribed temperature to the vicinity of the light beam path of the multipoint AF system (90a, 90b) via down-flow along the white arrows shown in fig. 3. Note that reference numeral UP denotes an unloading position at which the wafer is unloaded onto wafer table WTB, and reference numeral LP denotes a loading position at which the wafer is loaded onto wafer table WTB. In the present embodiment, the unloading position UP and the loading position LP are set symmetrically with respect to the straight line LV. The unloading position UP and the loading position LP can be set to the same position.

Fig. 8 shows a main configuration of a control system of the exposure apparatus 100. The control system is centered on a main control unit 20 constituted by a microcomputer (or a workstation) for controlling the whole system. In fig. 8, various sensors provided on measurement stage MST, such as uneven illuminance sensor 94, aerial image measuring device 96, and wavefront aberration sensor 98, are collectively referred to as a sensor group 99.

In the exposure apparatus 100 of the present embodiment configured as described above, since the arrangement of the X scale and the Y scale on the wafer table WTB as described above and the arrangement of the X head and the Y head as described above are employed, the X scale 39X is used in the effective stroke range of the wafer stage WST (i.e., the range moved for the alignment and exposure operation in the present embodiment) as shown in the examples of fig. 9 a and 9B₁、39X₂Are respectively opposite to the head units 62B and 62D (X head 66) and have a Y scale 39Y₁、39Y₂And a head unit 62A, 62C (X head 64) or a Y head 64Y₁、64y₂Must be respectively opposite. In fig. 9(a) and 9(B), the corresponding heads facing the X scale or the Y scale are indicated by circled frames.

Thus, the master control deviceApparatus 20 can control the positional information (including the rotation information in the θ z direction) of wafer stage WST in the XY plane with high accuracy by controlling each motor constituting stage drive system 124 based on the measured values of at least three of encoders 70A to 70D in the effective stroke range of wafer stage WST. Since the influence of air fluctuation on the measurement values of the encoders 70A to 70D is small enough to be almost negligible compared to the interferometer, the short-term stability of the measurement values due to air fluctuation is much better than that of the interferometer. In the present embodiment, the dimensions (e.g., the number of heads and/or the spacing) of head units 62A, 62B, 62C, and 62D are set in accordance with the effective stroke range of wafer stage WST, the size of the scale (i.e., the formation range of the diffraction grating), and the like. Therefore, in the effective stroke range of wafer stage WST, four scales 39X ₁、39X₂、39Y₁、39Y₂Although all of the four scales face the head units 62B, 62D, 62A, and 62C, respectively, not all of the four scales may face the corresponding head units. For example, X scale 39X₁、39X₂And/or a Y scale 39Y₁、39Y₂May also be disengaged from the readhead unit. When X scale 39X₁、39X₂One side of (2) or a Y scale 39Y₁、39Y₂When one of the three scales is disengaged from the head unit, the three scales still face the head unit in the effective stroke range of wafer stage WST, and therefore, the positional information of wafer stage WST in the X-axis, Y-axis, and θ z directions can be measured at any time. In addition, when the X scale 39X₁、39X₂One side of (2) or a Y scale 39Y₁、39Y₂When one of the two scales is separated from the head unit, the two scales face the head unit in the effective stroke range of wafer stage WST, and therefore, although the positional information of wafer stage WST in the θ z direction cannot be measured at any time, the positional information of the X axis and the Y axis can be measured at any time. At this time, the position of wafer stage WST may be controlled by using the position information of wafer stage WST in the θ z direction measured by interferometer system 118 in combination.

Further, wafer stage WST is driven in the X-axis direction as indicated by the white arrow in fig. 9(a)At this time, Y head 64 for measuring the position of wafer stage WST in the Y-axis direction is shown by arrow e in the figure ₁、e₂Shown sequentially switched to adjacent Y read heads 64. For example, from the Y read head 64 outlined by the solid circle to the Y read head 64 outlined by the dashed circle. Thus, the measurement values are continued before and after this switching. That is, in the present embodiment, in order to smoothly switch the Y heads 64 and connect the measured values, the interval between adjacent Y heads 64 provided in the head units 62A and 62C is set to be larger than the interval between the Y scales 39Y and 62C as described above₁、39Y₂The width in the X-axis direction is narrow.

In the present embodiment, the distance between adjacent Y heads 66 of the head units 62B and 62D is set to be larger than the X scale 39X as described above₁、39X₂Since the width in the Y-axis direction is narrow, similarly to the above, when wafer stage WST is driven in the Y-axis direction as indicated by the white arrow in fig. 9(B), X read heads 66 for measuring the position of wafer stage WST in the X-axis direction are sequentially switched to adjacent X read heads 66 (for example, X read heads 66 framed by a solid circle are switched to X read heads 66 framed by a dashed circle), and the measurement values are continued before and after the switching.

Next, the configuration of the encoders 70A to 70F will be described with the Y encoder 70A shown in fig. 10(a) in an enlarged scale as a representative. Fig. 10 a shows a Y scale 39Y on which detection light (measuring beam) is irradiated ₁A Y read head 64 of the read head unit 62A.

The Y head 64 is basically composed of three parts, i.e., an irradiation system 64a, an optical system 64b, and a light receiving system 64 c.

The irradiation system 64a includes a light source, for example, a semiconductor laser LD, for emitting a laser beam LB in a direction of 45 ° with respect to the Y axis and the Z axis, and a lens L1 disposed on the optical path of the laser beam LB emitted from the semiconductor laser LD.

The optical system 64b includes a polarizing beam splitter PBS whose separation plane is parallel to the XZ plane, a pair of mirrors R1a, R1b, lenses L2a, L2b, quarter wavelength plates (hereinafter referred to as λ/4 plates) WP1a, WP1b, mirrors R2a, R2b, and the like.

The light receiving system 64c includes a polarizer (light detector), a photodetector, and the like.

In the Y encoder 70A, the laser beam LB emitted from the semiconductor laser LD is incident on the polarization beam splitter PBS via the lens L1, and the polarized beam is split into two beams LB₁、LB₂. Light beam LB transmitted through polarizing beam splitter PBS₁Reaches Y scale 39Y formed by reflection mirror R1a₁The reflection type diffraction grating RG of (1), the light beam LB reflected by the polarization beam splitter PBS₂The reflection type diffraction lattice RG is reached via the mirror R1 b. Here, "polarized light separation" means separation of an incident light beam into a P-polarized light component and an S-polarized light component.

Using light beams LB₁、LB₂The diffraction beams, for example, the first-order diffraction beams generated from the diffraction grating RG of a predetermined number of times are converted into circularly polarized light by the λ/4 plates WP1a and WP1b via the lenses L2b and L2a, respectively, and then reflected by the mirrors R2a and R2b to pass through the λ/4 plates WP1a and WP1b again, and reach the polarization beam splitter PBS in the opposite direction of the same optical path as the outgoing path.

The two light beams that reach the polarization beam splitter PBS have their polarization directions rotated by 90 degrees with respect to the original direction. Thus, the light beam LB that is transmitted through the polarizing beam splitter PBS first₁The first diffracted beam (LB) is reflected by the Polarizing Beam Splitter (PBS), enters the light receiving system (64 c), and is reflected by the Polarizing Beam Splitter (PBS)₂The primary diffracted beam of (1) is transmitted through the polarizing beam splitter PBS and then is combined with the beam LB₁The resultant is coaxially incident on the light receiving system 64 c.

Next, the two primary diffracted light beams are aligned in the polarization direction by the light-receiving element in the light-receiving system 64c, and interfere with each other to be interference light, which is detected by the light detector and converted into an electric signal corresponding to the intensity of the interference light.

As is clear from the above description, in the Y encoder 70A, since the optical path lengths of the two light fluxes interfering with each other are extremely short and substantially equal, the influence of air fluctuation can be almost ignored. In addition, when the Y scale 39Y ₁That is, when wafer stage WST moves in the measurement direction (in this case, the Y-axis direction), the respective phases of the two light beams change, and the intensity of the interference light changes. The intensity change of the interference light is detected by the light receiving system 64c, and the position information corresponding to the intensity change is output as the measurement value of the Y encoder 70A. The other encoders 70B, 70C, 70D, etc. are also configured in the same manner as the encoder 70A. Each encoder uses an encoder having a resolution of, for example, about 0.1 nm. As shown in fig. 10(B), the encoder of the present embodiment uses, as the detection light, a laser beam LB having a cross-sectional shape extending in the periodic direction of the grid RG in the lateral direction. In fig. 10(B), the light beam LB is exaggeratedly illustrated compared to the lattice RG.

Further, the scale of the encoder is deformed by thermal expansion or the like with the lapse of use time, or the pitch of the diffraction grating is partially or entirely changed, and mechanical long-term stability is not achieved. Therefore, since the error included in the measurement value increases with the lapse of the use time, it is necessary to correct the error. Next, the correction of the lattice pitch and the correction of the lattice distortion of the scale performed by the exposure apparatus 100 according to the present embodiment will be described with reference to fig. 11.

In fig. 11, reference numerals IBY1 and IBY2 denote distance measuring beams with two optical axes out of a plurality of optical axes irradiated from the Y-axis interferometer 16 to the reflection surface 17a of the wafer table WTB, and reference numerals IBX1 and IBX2 denote distance measuring beams with two optical axes out of a plurality of optical axes irradiated from the X-axis interferometer 126 to the reflection surface 17b of the wafer table WTB. At this time, the distance measuring beams IBY1, IBY are arranged symmetrically with respect to the straight line LV (which coincides with a straight line connecting the centers of the plurality of X heads 66), and the substantial distance measuring axis of the Y-axis interferometer 16 coincides with the straight line LV. Therefore, the Y position of wafer table WTB can be measured without Abbe (Abbe) error by using Y-axis interferometer 16. Similarly, the distance measuring beams IBX1 and IBX2 are symmetrically arranged with respect to a straight line LH (coinciding with a straight line connecting the centers of the plurality of Y heads 64) passing through the optical axis of the projection optical system PL and parallel to the X axis, and the substantial distance measuring axis of the X-axis interferometer 126 coincides with a straight line LH passing through the optical axis of the projection optical system PL and parallel to the X axis. Therefore, the X position of wafer table WTB can be measured without Abbe (Abbe) error by using X-axis interferometer 126.

First, the correction of the pitch between the grid line deformation (grid line bending) on the X scale and the grid line on the Y scale will be described. For simplicity of explanation, the reflecting surface 17b is assumed to be an ideal plane.

First, main controller 20 drives wafer stage WST based on the measurement values of Y-axis interferometer 16 and X-axis interferometer 126, positions wafer stage WST such that Y scale 39Y is located as shown in fig. 11₁And 39Y₂Arranged directly below (at least one) each of the corresponding head units 62A, 62D, and a Y scale 39Y₁、39Y₂One end on the (diffraction grating) + Y side is located at a position corresponding to each of the corresponding head units 62A and 62C.

Next, the main controller 20 fixes the measurement value of the X-axis interferometer 126 to a predetermined value at a low speed at which short-term variation of the measurement value of the Y-axis interferometer 16 can be ignored, and the Y-axis interferometer 16 and the Z sensor 74 are used as the basis of the main controller 20_1，4、74_2，4、76_1，3、76_2，3While maintaining all of the pitch amount, roll amount, and yaw amount at zero, wafer stage WST is moved in the + Y direction indicated by an arrow in fig. 11, for example, until Y scale 39Y₁、39Y₂Until the other end (one end on the Y side) of the same coincides with the corresponding head units 62A, 62C (within the effective stroke range described above). During this movement, the main controller 20 takes in the measurement values of the Y linear encoders 70A, 70C and the measurement value of the Y-axis interferometer 16 (the measurement values of the measurement beams IBY1, IBY 2) at predetermined sampling intervals, and obtains the relationship between the measurement values of the Y linear encoders 70A, 70C and the measurement value of the Y-axis interferometer 16 from the taken-in measurement values. That is, main controller 20 obtains Y marks arranged in order of facing direction on head units 62A and 62C as wafer stage WST moves Ruler 39Y₁、39Y₂The grid pitch (the interval between adjacent grid lines) and correction information of the grid pitch. The correction information can be obtained as a correction map or the like in which the relationship between the interferometer measurement value and the encoder measurement value is represented as a curve, for example, when the horizontal axis is the interferometer measurement value and the vertical axis is the encoder measurement value. In this case, the measurement value of Y-axis interferometer 16 does not include a long-term variation error, but hardly includes a short-term variation error due to air fluctuation or the like because of the value obtained when wafer stage WST is scanned at the extremely low speed, and can be regarded as a correct value in which the error can be ignored. In addition, when the range is within the above range, wafer stage WST may be moved in the-Y direction as indicated by arrow F' in fig. 11, and Y scale 39Y may be obtained through the same procedure as described above₁、39Y₂The grid pitch (the interval between adjacent grid lines) and correction information of the grid pitch. Here, though along the Y scale 39Y₁、39Y₂The wafer stage WST is driven in the Y axis direction with both ends thereof crossing the range of the corresponding head units 62A, 62C, but the present invention is not limited to this, and the wafer stage WST may be driven in the range of the Y axis direction in which the wafer stage WST moves during the exposure operation of the wafer, for example.

Further, main controller 20 is arranged to face X scale 39X in order along with the movement of wafer stage WST during the movement of wafer stage WST ₁、39X₂The measurement values obtained by the plurality of X readheads 66 of the readhead units 62B and 62D and the measurement value of the Y-axis interferometer 16 corresponding to each measurement value are subjected to predetermined statistical calculations to obtain correction information of deformation (warp) of the grid line 37 sequentially facing the plurality of X readheads 66. At this time, the main controller 20 calculates, for example, the positions of the scales 39X arranged in order facing each other₁、39X₂The measurement values (or weighted average) of the plurality of heads of the head units 62B and 62D of (a) and the like are used as correction information of the grid warp. This is because, when the reflecting surface 17b is an ideal plane, since the same blur pattern should repeatedly appear during the process of transporting the wafer stage WST in the + Y direction or the-Y direction, it is possible to accurately average the measurement data acquired by the plurality of X read heads 66Correction information of deformation (warp) of the grid line 37 sequentially facing the plurality of reading heads 66 is obtained.

When the reflecting surface 17b is not an ideal plane, the unevenness (curvature) of the reflecting surface is measured in advance to obtain correction data of the curvature. Next, when wafer stage WST is moved in the + Y direction or the-Y direction, wafer stage WST can be accurately moved in the Y-axis direction by controlling the X position of wafer stage WST based on the correction data, instead of fixing the measurement value of X-axis interferometer 126 to a predetermined value. In this way, correction information of the grid pitch of the Y scale and correction information of deformation (bending) of the grid line 37 can be obtained in the same manner as described above. Further, since the measurement data acquired by the plurality of X heads 66 is a plurality of data in which the reflection surface 17b is referenced at different positions, and since each of the heads measures the deformation (bending) of the same grid line, there is an additional effect that the bending correction residual error of the reflection surface is averaged and approaches a true value by the above-described averaging operation (in other words, the influence of the bending residual error can be reduced by averaging the measurement data (bending information of the grid line) acquired by the plurality of heads).

Next, correction of the pitch between the grid line deformation (grid line bending) on the Y scale and the grid line on the X scale will be described. For simplicity of explanation, the reflecting surface 17a is assumed to be an ideal plane. In this case, the X-axis direction and the Y-axis direction may be exchanged to perform the process in the above correction.

That is, first, main controller 20 drives wafer stage WST to position wafer stage WST such that X scale 39X is positioned₁And 39X₂Arranged directly below (at least one) the corresponding head units 62B and 62D, and an X scale 39X₁、39X₂One end of the (diffraction grating) + Y side (or-X side) is located at a position corresponding to each of the head units 62B, 62C. Next, the main controller 20 fixes the measurement values of the Y-axis interferometer 16 to predetermined values at a low speed at which short-term variation of the measurement values of the X-axis interferometer 126 can be ignored, and the main controller is controlled by the X-axis interferometer 126 and the likeThe measured value is obtained by moving wafer stage WST in the + X direction (or-X direction) until, for example, X scale 39X while maintaining the pitch, roll, and yaw at zero₁、39X₂Until the other end (one end on the Y side (or + Y side)) of the same coincides with the corresponding head units 62A, 62C (within the effective stroke range described above). During this movement, the main controller 20 takes in the measurement values of the X linear encoders 70B, 70D and the measurement value of the X-axis interferometer 126 (measurement values of the measurement beams IBX1, IBX 2) at predetermined sampling intervals, and obtains the relationship between the measurement values of the X linear encoders 70B, 70D and the measurement value of the X-axis interferometer 126 from the taken measurement values. That is, main controller 20 obtains X scale 39X disposed in order of facing direction of head units 62B and 62D as wafer stage WST moves ₁、39X₂And correction information of the lattice pitch. The correction information can be obtained as a correction map or the like in which the relationship between the interferometer measurement value and the encoder measurement value is represented as a curve, for example, when the horizontal axis is the interferometer measurement value and the vertical axis is the encoder measurement value. In this case, the measurement value of X-axis interferometer 126 does not include a long-term variation error because of the value obtained when wafer stage WST is scanned at the extremely low speed, and also includes almost no short-term variation error due to air fluctuation or the like, and can be regarded as a correct value in which the error can be ignored.

Further, main controller 20 is arranged to face Y scale 39Y in order in accordance with the movement of wafer stage WST during the movement thereof₁、39Y₂The measurement values obtained by the plurality of X readheads 64 of the readhead units 62A and 62C and the measurement values of the X-axis interferometer 126 corresponding to the respective measurement values are subjected to predetermined statistical calculations to obtain correction information of the distortion (warp) of the grid line 38 sequentially facing the plurality of Y readheads 64. At this time, the main controller 20 calculates the positions of the scales 39Y arranged in order facing each other₁、39Y₂The measurement values (or weighted average) of the plurality of heads of the head units 62A and 62C, and the like are used as correction information of the grid warp. This is because, when reflecting surface 17a is an ideal plane, wafer stage WST is carried in the + X direction or the-X direction Since the same blur pattern should be repeated, correction information of the deformation (warp) of the grid line 38 sequentially facing the plurality of the Y heads 64 can be accurately obtained by averaging the measurement data acquired by the plurality of the Y heads 64.

When the reflecting surface 17a is not an ideal plane, the unevenness (curvature) of the reflecting surface is measured in advance to obtain correction data of the curvature. Next, when wafer stage WST is moved in the + X direction or the-X direction, wafer stage WST can be accurately moved in the X-axis direction by controlling the Y position of wafer stage WST based on the correction data, instead of fixing the measurement value of Y-axis interferometer 16 to a predetermined value. In this way, correction information of the grid pitch of the X scale and correction information of deformation (bending) of the grid line 38 can be obtained in the same manner as described above.

The main controller 20 obtains correction information of the grid pitch of the Y scale and correction information of deformation (warp) of the grid line 37, and obtains correction information of the grid pitch of the X scale and correction information of deformation (warp) of the grid line 38 at a predetermined timing, for example, for each lot.

Next, in the exposure process of the wafers in the lot, main controller 20 corrects the measurement values obtained from head units 62A and 62C (i.e., the measurement values of encoders 70A and 70C) based on the correction information of the lattice pitch of the Y scale and the correction information of the deformation (warp) of lattice line 38, and controls the position of wafer stage WST in the Y axis direction. Thus, the position of wafer stage WST in the Y-axis direction can be controlled with good accuracy using Y linear encoders 70A, 70C, without being affected by the change over time in the grid pitch of the Y scale and the warp of grid line 38.

In the exposure process of the wafers in the lot, main controller 20 controls the position of wafer stage WST in the X-axis direction while correcting the measurement values obtained by head units 62B and 62D (i.e., the measurement values of encoders 70B and 70D) based on the correction information of the grid pitch of the X scale and the correction information of the deformation (warp) of grid line 38. This makes it possible to accurately control the position of wafer stage WST in the X-axis direction using X linear encoders 70B and 70D without being affected by the change in the grid pitch of the X scale with time and the bending of grid line 37.

In the above description, the Y scale 39Y is used₁、39Y₂And X scale 39X₁、39X₂Correction information of the grid pitch and the grid line bending is obtained, but the present invention is not limited to this, and only the Y scale 39Y may be used₁、39Y₂And X scale 39X₁、39X₂The correction information of the grid pitch and the grid line curvature may be acquired, or the Y scale 39Y may be used₁、39Y₂And X scale 39X₁、39X₂Both of them acquire correction information of either the grid pitch or the grid line curvature. For example, when only correction information of grid line bending is acquired, wafer stage WST may be moved in the Y-axis direction based on only the measurement values of Y linear encoders 70A and 70C without using Y-axis interferometer 16, or wafer stage WST may be moved in the X-axis direction based on only the measurement values of X linear encoders 70B and 70D without using X-axis interferometer 126.

Next, wafer alignment by the exposure apparatus 100 of the present embodiment will be briefly described with reference to fig. 12(a) to 12 (C). Further, the details thereof will be left to later.

Here, an operation will be described in which sixteen irradiation regions AS colored on the wafer W having a plurality of irradiation regions formed in the arrangement (irradiation pattern) shown in fig. 12C are used AS the alignment irradiation regions. Note that in fig. 12(a) and 12(B), the measurement stage MST is not shown.

As a precondition, the second alignment system AL2₁～AL2₄The position in the X-axis direction is adjusted in advance in accordance with the arrangement of the alignment irradiation region AS. In addition, the second alignment system AL2₁～AL2₄The specific position adjustment method of (1) is left to be described later.

First, main controller 20 positions the center of wafer W at wafer stage LPThe WST is moved obliquely upward to the left in fig. 12 a, and is positioned at a predetermined position (alignment start position described later) where the center of the wafer W is located on the straight line LV. The movement of wafer stage WST at this time is performed by main controller 20 driving the motors of stage drive system 124 based on the measurement values of X encoder 70D and the measurement values of Y-axis interferometer 16. In a state of being positioned at the alignment start position, the position (including the θ z rotation) of wafer table WTB on which wafer W is mounted in the XY plane is controlled so as to face X scale 39X ₁、39X₂The two heads 66 of the head unit 62D have measured values and the measured values respectively face the Y scale 39Y₁、39Y₂Y read head 64Y of₂、64y₁Measurements of (four encoders).

Next, main controller 20 moves wafer stage WST in the + Y direction by a predetermined distance based on the measurement values of the four encoders to position it at the position shown in fig. 12(a), and uses first alignment system AL1 and second alignment system AL2₂、AL2₃The alignment marks (see the star marks in fig. 12 a) attached to the three first alignment shot areas AS are simultaneously and independently detected, and the three alignment systems AL1 and AL2 are used₂、AL2₃The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other. In addition, the second alignment system AL2 for not detecting both ends of the alignment mark at this time₁、AL2₄The wafer table WTB (or wafer) may be irradiated with the detection light or not. In the wafer alignment of the present embodiment, the position of wafer stage WST in the X-axis direction is set so that first alignment system AL1 is disposed on the center line of wafer table WTB, and first alignment system AL1 detects alignment marks in an alignment irradiation region located on the meridian line of the wafer. Further, although the alignment marks may be formed inside each shot region on the wafer W, in the present embodiment, the alignment marks are formed outside each shot region, that is, on the block boundary lines (scribe lines) that demarcate a plurality of shot regions of the wafer W.

Next, the main control deviceWafer stage WST is moved a predetermined distance in the + Y direction based on the measurements of the four encoders, and is positioned so that five alignment systems AL1 and AL2 can be used₁～AL2₄The positions of the alignment marks of five second alignment shot areas AS attached to the wafer W are simultaneously and independently detected, and the five alignment systems AL1 and AL2 are used₁～AL2₄The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other.

Next, main controller 20 moves wafer stage WST in the + Y direction by a predetermined distance based on the measurement values of the four encoders, and positions it so that it can use five alignment systems AL1 and AL2₁～AL2₄The positions of the alignment marks of the five third alignment shot regions AS attached to the wafer W are simultaneously and independently detected, and five alignment systems AL1 and AL2 are used₁～AL2₄Five alignment marks (see star marks in fig. 12B) are simultaneously and independently detected, and the five alignment systems AL1 and AL2 are used₁～AL2₄The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other.

Next, main controller 20 moves wafer stage WST in the + Y direction by a predetermined distance based on the measurement values of the four encoders, and positions it so that first alignment system AL1 and second alignment system AL2 can be used ₂、AL2₃The positions of the alignment marks of the three first alignment shot areas AS attached to the wafer W are simultaneously and independently detected, and the three alignment systems AL1 and AL2 are used₂、AL2₃Three alignment marks (see star marks in fig. 12B) are detected simultaneously and independently, and the three alignment systems AL1 and AL2 are used₂、AL2₃The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other.

Next, the main control device 20 uses the total of sixteen obtained in the above mannerThe detection result of each alignment mark and the corresponding measured values of the four encoders, and a second alignment system Al2_nThe base lines of (a) are statistically calculated by, for example, the EGA method disclosed in japanese patent application laid-open No. 61-44429 (corresponding to U.S. Pat. No. 4,780,617), and the like, to calculate the arrangement of all the irradiation regions on the wafer W on a coordinate system (for example, an XY coordinate system with the optical axis of the projection optical system PL as the origin) defined by the measurement axes of the four encoders (four head units).

AS described above, in the present embodiment, by moving wafer stage WST in the + Y direction and positioning wafer stage WST at four positions on the movement path, it is possible to obtain positional information of alignment irradiation areas AS with the alignment marks at a total of sixteen positions in a shorter time AS compared with a case where sixteen alignment irradiation areas AS are detected in order by a single alignment system. In this case, in particular, for example, the alignment systems AL1, AL2 ₂、AL2₃It can be easily seen that these alignment systems AL1, AL2₂、AL2₃In conjunction with the movement of wafer stage WST, a plurality of alignment marks arranged in the Y-axis direction and sequentially arranged in a detection area (corresponding to, for example, an irradiation area of detection light) are detected. Therefore, it is not necessary to move wafer stage WST in the X-axis direction when the alignment mark is measured.

In this case, the number of detection points (the number of measurement points) of the alignment marks on the wafer W detected by the plurality of alignment systems at substantially the same time differs depending on the position of the wafer stage WST in the XY plane (particularly, the Y position (the ratio of the wafer W entering the plurality of alignment systems)). Therefore, when wafer stage WST is moved in the Y-axis direction orthogonal to the arrangement direction (X-axis direction) of the plurality of alignment systems, marks at different positions on wafer W are simultaneously detected using a required number of alignment systems in accordance with the position of wafer stage WST, in other words, in accordance with the arrangement of the irradiation regions on wafer W.

In addition, the surface of the wafer W is not generally perfectly flat but is somewhat uneven. Therefore, only when the wafer table WTB is simultaneously measured by the plurality of alignment systems at a certain position in the Z-axis direction (direction parallel to the optical axis AX of the projection optical system PL), there is a high possibility that at least one alignment system detects the alignment mark in a defocused state. Therefore, in the present embodiment, the measurement error of the alignment mark position due to the detection of the alignment mark in the defocus state is suppressed in the following manner.

That is, main controller 20 changes a plurality of alignment systems AL1 and AL2 by a Z leveling mechanism, not shown, constituting a part of stage drive system 124, for each positioning position of wafer stage WST for detecting an alignment mark in each alignment irradiation area described above₁～AL2₄Relative positional relationship in the Z-axis direction (focusing direction) perpendicular to the XY plane between wafer W mounted on wafer table WTB (wafer stage WST) and stage drive system 124(Z leveling mechanism) and alignment systems AL1 and AL2 are controlled₁～AL2₄So that the alignment marks formed at the different positions on the wafer W are detected substantially simultaneously by the alignment systems corresponding to the alignment marks.

Fig. 13(a) to 13(C) show five alignment systems AL1 and AL2 in the state shown in fig. 12(B) where wafer stage WST is positioned at the alignment mark detection position in the third alignment irradiation region₁～AL2₄The condition of the mark on the wafer W is detected. In FIGS. 13A to 13C, wafer table WTB (wafer W) is positioned at different Z positions and alignment systems AL1 and AL2 are used₁～AL2₄To detect the situation of different alignment marks simultaneously. In the state of fig. 13(a), the alignment system AL2 at both ends₁、AL2₄The remaining alignment system is in focus and out of focus. In the state of fig. 13(B), the alignment system AL2 ₂And AL2₃The remaining alignment system is in focus and out of focus. In the state of fig. 13(C), only the central alignment system AL1 is in focus while the remaining alignment systems are out of focus.

Thus, by changing the Z position of wafer table WTB (wafer W),to change a plurality of alignment systems AL1, AL2₁～AL2₄Alignment systems AL1 and AL2 are used to align wafers W mounted on wafer table WTB (wafer stage WST) in the Z-axis direction (focusing direction)₁～AL2₄The alignment marks are detected so that either alignment system can measure the alignment marks substantially in the best focus state. Therefore, in each alignment system, the main controller 20 preferentially uses the mark detection result in the best focus state, for example, and can detect the marks formed at different positions on the wafer W with good accuracy, without being affected by the irregularities on the surface of the wafer W and the difference in the best focus of the plurality of alignment systems.

In the above description, for example, the mark detection result in the best in-focus state is preferentially used in each alignment system, but the present invention is not limited to this, and the main controller 20 may determine the position information of the alignment mark using the mark detection result in the out-of-focus state. In this case, the mark detection result in the defocus state can also be used by multiplying the weight corresponding to the defocus state. Further, depending on the material of a layer formed on the wafer, for example, the mark detection result in the defocus state may be better than the mark detection result in the best focus state. In this case, the mark may be detected in a focused state, that is, a defocused state, which provides the best result for each alignment system, and the position information of the mark may be obtained using the detection result.

As can be seen from fig. 13 a to 13C, the optical axes of all the alignment systems do not always exactly coincide with the same ideal direction (Z-axis direction), and the result of detecting the position of the alignment mark may contain an error due to the influence of the inclination (parallelism) of the optical axes with respect to the Z-axis. Therefore, it is preferable to measure the tilt of the optical axes of all the alignment systems with respect to the Z-axis in advance, and correct the position detection result of the alignment mark based on the measurement result.

Next, a baseline measurement (baseline check) of the first alignment system AL1 is explained. Here, the baseline of the first alignment system AL1 refers to the positional relationship (or distance) between the projection position of the pattern (e.g., the pattern of the reticle R) of the projection optical system PL and the detection center of the first alignment system AL 1.

a. At the time of starting the baseline measurement by the first alignment system AL1, as shown in fig. 14(a), the nozzle unit 32 forms the liquid immersion area 14 between the projection optical system PL and at least one of the measurement table MTB and the CD bar 46. That is, wafer stage WST and measurement stage MST are separated from each other.

When the baseline measurement of the first alignment system AL1 is performed, the main controller 20 first detects (observes) the fiducial mark FM (see the star symbol in fig. 14 a) located at the center of the measurement plate 30 by the first alignment system AL1 as shown in fig. 14 a. Next, the main control device 20 stores the detection result of the first alignment system AL1 and the measurement values of the encoders 70A to 70D at the time of detection in a memory in a corresponding relationship with each other. Hereinafter, for convenience of explanation, this process will be referred to as the first half of the Pri-BCHK process. During the first half of the Pri-BCHK processing, the wafer table WTB is positioned in the XY plane so as to face the X scale 39X ₁、39X₂Two X-ray heads 66 (encoders 70B, 70D) shown in a circle in FIG. 14A, and a Y scale 39Y facing the Y scale₁、39Y₂Two Y-read heads 64Y shown in FIG. 14(A) as circled boxes₂、64y₁(encoders 70A, 70C).

b. Next, main controller 20 starts moving wafer stage WST in the + Y direction so that measurement plate 30 is positioned directly below projection optical system PL as shown in fig. 14 (B). After the start of the movement of wafer stage WST in the + Y direction, main control device 20 detects the approach of wafer stage WST to measurement stage MST based on the outputs of gap detection sensors 43A and 43C, and starts opening shutters 49A and 49B via drive mechanisms 34A and 34B before and after this movement, that is, during the movement of wafer stage WST in the + Y direction, to allow wafer stage WST and measurement stage MST to approach further by opening the shutters. The main control device 20 checks the opening of the shutters 49A and 49B based on the detection result of the open/close sensor 101.

c. Next, when main controller 20 detects that wafer stage WST and measurement stage MST are in contact with each other (or close to a distance of about 300 μm) based on the outputs of collision detection sensors 43B and 43C, wafer stage WST is temporarily stopped immediately. Thereafter, main controller 20 further integrally moves wafer stage WST and measurement stage MST in the + Y direction while keeping them in contact with each other (or while keeping a distance of about 300 μm). Then, the liquid immersion area 14 is transferred from the CD bar 46 to the wafer table WTB while moving.

d. Next, when wafer stage WST reaches the position shown in fig. 14B, main control apparatus 20 stops both stages WST and MST, and measures a pair of measurement mark projected images (aerial images) on reticle R projected by projection optical system PL using aerial image measuring apparatus 45 including measurement plate 30. For example, the aerial image measuring operation of the slit scanning system using the pair of aerial image measuring slit patterns SL may be performed by the same method as that disclosed in the aforementioned japanese patent application laid-open No. 2002-14005 (corresponding to the specification of U.S. patent application publication No. 2002/0041377), and the aerial images of the pair of measuring marks may be measured, respectively, and the measurement results (the aerial image intensities corresponding to the XY positions of the wafer table WTB) may be stored in the memory. For convenience of explanation, the aerial image measurement process of the pair of measurement marks on the reticle R will be referred to as the second half of Pri-BCHK. During the second half of the Pri-BCHK process, the position of the wafer table WTB in the XY plane is opposite to the X scale 39X₁、39X₂Two X-ray heads 66 (encoders 70B, 70D) shown in a circle in FIG. 14B, and a Y scale 39Y facing the Y scale₁、39Y₂Shown in fig. 14(B) as circles, the two Y read heads 64 (encoders 70A, 70C) are controlled.

Subsequently, the main controller 20 calculates a baseline of the first alignment system AL1 from the first half processing result of Pri-BCHK and the second half processing result of Pri-BCHK.

As described above, at the time when the baseline measurement of first alignment system AL1 ends (i.e., at the time when the second half of Pri-BCHK processing ends), measurement stage MST and wafer stage WST are in contact with each other (or separated from each other by a distance of about 300 μm).

Next, a description will be given mainly of the second alignment system AL2 performed before starting the processing of the batch of wafers (batch head)_n(n is 1-4) a baseline measurement operation. Second alignment System AL2 herein_nThe base line of (A) is each of the second alignment systems AL2 with (the center of detection of) the first alignment system AL1 as a reference_nRelative position of (detection center of). In addition, a second alignment system AL2_n(n is 1 to 4) and is driven by the rotary drive mechanism 60 according to the irradiation pattern data of the wafers in the lot_nThe position in the X-axis direction is set by driving.

e. In the baseline measurement of the second alignment system (hereinafter, also referred to as Sec-BCHK as appropriate) performed at the top of the lot, the main controller 20 first detects a specific alignment mark (see the star mark in fig. 15 a) on the wafer W (process wafer) at the top of the lot by the first alignment system AL1 as shown in fig. 15 a, and stores the detection result and the measurement values of the detection-time encoders 70A to 70D in the memory in a corresponding relationship with each other. In the state of fig. 15(a), the position of wafer table WTB in the XY plane is opposite to X scale 39X ₁、39X₂Two X read heads 66 (encoders 70B, 70D), and a scale 39Y facing the Y₁、39Y₂Two Y read heads 64Y₂、64y₁(encoders 70A, 70C) controlled by the main controller 20.

f. Next, main controller 20 moves wafer stage WST in the-X direction by a predetermined distance, and uses second alignment system AL2 as shown in fig. 15(B)₁The specific alignment mark (see the star mark in fig. 15B) is detected, and the detection result and the measurement values of the encoders 70A to 70D at the time of detection are associated with each other and stored in the memory. In the state of FIG. 15(B), the position of wafer table WTB in the XY plane is based on the opposite to X scale 39X₁、39X₂Two X read heads 66 (encoders 70B, 70D), and a scale 39Y facing the Y₁、39Y₂Two of (2)The Y read heads 64 (encoders 70A, 70C).

g. Similarly, main controller 20 sequentially moves wafer stage WST in the + X direction using remaining second alignment system AL2₂、AL2₃、AL2₄The specific alignment marks are sequentially detected, and the detection result and the measurement values of the encoders 70A to 70D at the time of detection are sequentially associated with each other and stored in a memory.

h. Next, the main controller 20 calculates each second alignment system AL2 based on the processing result of the above-described e and the processing result of the above-described f or g _nA baseline of (c).

Thus, since the first wafer W (handle wafer) can be used in a batch, the first alignment system AL1 and each second alignment system AL2 can be used_nThe same alignment mark on the wafer W is detected to obtain each second alignment system AL2_nThe base line of (2) is processed, and as a result, the detection offset error between the alignment systems due to the processing is also corrected. In addition, second alignment system AL2 may be performed using fiducial marks on wafer stage WST or measurement stage MST instead of alignment marks for the wafer_nIs measured at the baseline. In this case, the reference marks FM of the measuring plate 30 used for the baseline measurement of the first alignment system AL1 may also be used, i.e. the second alignment system AL2_nTo detect the fiducial marks FM, respectively. Alternatively, the system may be aligned with the second alignment system AL2_nProviding n reference marks on wafer stage WST or measurement stage MST in the same position relation, and using second alignment system AL2_nThe detection of the reference marks is performed substantially simultaneously. The reference mark may be, for example, a reference mark M of the CD bar 46. Further, the second alignment system AL2 can be set to a predetermined positional relationship with respect to the reference mark FM for baseline measurement by the first alignment system AL1_nIs provided on wafer stage WST, and second alignment system AL2 is executed substantially simultaneously with the detection of fiducial marks FM by first alignment system AL1 _nDetection of fiducial marks FM. At this point in time the second alignment system AL2_nThe reference mark for baseline measurement of (2) may be one, or may beMay be plural, e.g. with the second alignment system AL2_nAre provided in the same number. In the present embodiment, the first alignment system AL1 and the second alignment system AL2 are used_nCan detect two-dimensional markers (X, Y markers) respectively, and therefore by using the second alignment system AL2_nUsing a two-dimensional marker for the baseline measurement, the second alignment system AL2 can be determined simultaneously_nThe base lines in the X-axis and Y-axis directions of (1). In the present embodiment, the fiducial marks FM, M and the alignment mark of the wafer include, for example, one-dimensional X marks and Y marks in which a plurality of line marks are periodically arranged in the X-axis direction and the Y-axis direction, respectively.

Next, the Sec-BCHK operation performed during wafer replacement at a predetermined timing, for example, during a period from the end of exposure of a wafer to the end of the next wafer loading operation onto wafer table WTB, in wafer processing in a lot will be described. Since Sec-BCHK is performed at a time interval for each wafer replacement, Sec-BCHK (time interval) is hereinafter also referred to as Sec-BCHK.

During the Sec-BCHK (time interval), main controller 20 moves measurement stage MST such that straight line LV, in which the detection center of first alignment system AL1 is disposed, substantially coincides with center line CL, and CD lever 46, first alignment system AL1, and second alignment system AL2, as shown in FIG. 16 _nAre opposite. Then, the Y read head 64Y shown in a circle frame in FIG. 16 is opposed to each of the pair of reference lattices 52 on the CD bar 46₁、64y₂The measurements (Y-axis linear encoders 70E, 70F) adjust the θ z rotation of CD bar 46 and the XY position of CD bar 46 based on the measurements from a first alignment system AL1, shown circled in fig. 16, that detects a fiducial mark M located on or near the centerline CL of measurement table MTB, and uses the measurements of, for example, an interferometer.

Next, in this state, master control device 20 uses four second alignment systems AL2₁～AL2₄The reference marks M on the CD rod 46 in the field of view of the second alignment systems are measured simultaneously to determine four second alignment systems AL2 in each case₁～AL2₄A baseline of (c). Then, by carrying out the followingThe newly measured baselines are used during processing to correct the four second alignment systems AL2₁～AL2₄Drift of the baseline of (a).

Although the above-mentioned Sec-BCHK (time interval) measures different reference marks at the same time by the plurality of second alignment systems, the present invention is not limited to this, and the same reference mark M on the CD bar 46 may be measured sequentially (non-simultaneously) by the plurality of second alignment systems to determine four second alignment systems AL2, respectively ₁～AL2₄A baseline of (c).

Next, the second alignment system AL2 will be briefly described with reference to fig. 17(a) and 17(B)_nAnd (4) a position adjusting action.

Before adjustment, the first alignment system AL1 and the four second alignment systems AL2₁～AL2₄The positional relationship (2) is the positional relationship of fig. 17 (a).

As shown in fig. 17(B), main controller 20 moves measurement stage MST such that first alignment system AL1 and four second alignment systems AL2₁～AL2₄Above the CD bar 46. Then, as in the case of Sec-BCHK (time interval), the Y-axis linear encoders 70E, 70F (Y head 64Y) are used₁、64y₂) Adjusts the theta z rotation of the CD bar 46 and adjusts the XY position of the CD bar 46 in accordance with the measurements of the first alignment system AL1 for detecting the fiducial mark M located on or near the centerline CL of the measurement table MTB. At the same time, the main controller 20 drives the rotation driving mechanism 60 based on the irradiation pattern information including the size and arrangement of the alignment irradiation area on the wafer to be subjected to the next exposure (i.e., the arrangement of the alignment marks on the wafer)₁～60₄So as to be provided in each second alignment system AL2_nThe arms 56 at the distal ends rotate about their respective centers of rotation as indicated by arrows in fig. 17 (B). At this time, the main control device 20 monitors the second alignment systems AL2 _nThe desired reference mark M on the CD bar 46 enters each of the second alignment systems AL2_nThe rotation of each arm 56 is stopped at the position of the field of view (detection region). Thereby, fitting to the alignment to be detectedThe configuration of the alignment marks of the illuminated area to adjust (change) the second alignment system AL2_nA baseline of (c). I.e. change the second alignment system AL2_nThe position of the detection region in the X-axis direction. Thus, the wafers W can pass through the respective second alignment systems AL2 only by moving the wafers W in the X-axis direction_nA plurality of alignment marks having substantially the same position in the X-axis direction and different positions in the Y-axis direction on the wafer W are sequentially detected. In the present embodiment, the wafer alignment operations, i.e., the first alignment system AL1 and the second alignment system AL2_nThe detection operation of the alignment mark on the wafer W is to move the wafer W only in one dimension in the Y-axis direction as described later, but at least one second alignment system AL2 may be provided in the middle of the detection operation_nThe detection region of (b) and the wafer W are relatively moved in a direction (for example, X-axis direction) different from the Y-axis direction. At this point, though, the second alignment system AL2 may be used_nThe position of the detection region is adjusted by the movement of (3), but only the wafer W may be moved in consideration of the adjustment time, the change in the baseline, and the like.

Next, the second alignment system AL2 is adjusted in the manner described above_nAfter baseline, main control device 20 enables each vacuum pad 58_nAct to move each arm 56_nIs fixed by suction to a main frame, not shown. Thereby maintaining each arm 56_nThe state after the adjustment of the rotation angle of (1).

In addition, in the above description, five alignment systems AL1, AL2 have been used₁～AL2₄The fiducial marks M formed at different positions on the CD bar 46 are detected simultaneously and independently, but not limited thereto, and five alignment systems AL1 and AL2 may be used₁～AL2₄So as to simultaneously and independently detect alignment marks formed at different positions on a wafer W (a processed wafer), and adjust each arm 56_nThereby simultaneously adjusting the second alignment system AL2_nA baseline of (c). In the present embodiment, the second alignment system AL2 is adjusted using the reference mark M of the CD bar 46 or the like_nThe adjustment operation is not limited to this, and the second alignment system AL2 may be measured by the aforementioned sensor, for example_nPosition ofSet aside to move it to the target position. At this point, a second alignment system AL2 measured from the sensor may be employed_nTo correct the baseline measurement before the movement, to perform the baseline measurement again after the movement, or to perform at least a second alignment system AL2 after the movement _nThe procedure of baseline measurement of (a).

Next, detection of positional information (surface positional information) of the front surface of the wafer W in the Z-axis direction (hereinafter referred to as a focus map) by the exposure apparatus 100 according to the present embodiment will be described.

When this focus mapping is performed, the main controller 20 faces the X scale 39X as shown in fig. 18(a)₂And an X-ray reading head 66 (X-ray linear encoder 70D) and a Y scale 39Y facing each other₁、39Y₂Two Y read heads 64Y₂、64y₁(Y linear encoders 70A, 70C) to manage the position of wafer table WTB in the XY plane. In the state of fig. 18 a, a straight line (center line) parallel to the Y axis passing through the center of wafer table WTB (substantially coincident with the center of wafer W) coincides with straight line LV.

Next, in this state, main controller 20 starts Scanning (SCAN) of wafer stage WST in the + Y direction, and after the start of scanning, Z sensors 72a to 72d are operated (turned on) together with the multipoint AF systems (90a, 90b) while wafer stage WST is moving in the + Y direction until the detection beams of multipoint AF systems (90a, 90b) start to irradiate wafer W.

Next, in a state where Z sensors 72a to 72d operate simultaneously with multipoint AF systems (90A and 90B), while wafer stage WST is moving in the + Y direction as shown in fig. 18B, position information (surface position information) of the surface of wafer table WTB (the surface of plate body 28) measured by Z sensors 72a to 72d in the Z-axis direction and position information (surface position information) of the surface of wafer W in the Z-axis direction at a plurality of detected points detected by multipoint AF systems (90A and 90B) are taken in at predetermined sampling intervals, and the taken three of the surface position information and the measured values of Y linear encoders 70A and 70C at the time of each sampling are associated with each other and stored in a memory (not shown) in order.

Next, when the detection beams of the multipoint AF systems (90a, 90b) are not irradiated onto the wafer W, the main controller 20 ends the above-described sampling operation, and converts the surface position information of the respective detection points of the multipoint AF systems (90a, 90b) into data based on the surface position information of the Z sensors 72a to 72d that is simultaneously captured.

More specifically, the region near the end of the plate 28 near the X-side end (where the Y scale 39Y is formed) is determined from the average of the measurements of the Z sensors 72a and 72b₂Area(s) of the detected points (e.g., the midpoint of the respective measurement points of the Z sensors 72a and 72b, that is, a point on the X axis corresponding to substantially the same arrangement as the plurality of detection points of the multipoint AF systems (90a and 90b), and hereinafter referred to as a left measurement point). Further, the region near the + X-side end of the plate 28 (where the Y scale 39Y is formed) is obtained from the measurement values of the Z sensors 72c and 72d₁Area(s) of the detected points (e.g., the midpoint of the respective measurement points of the Z sensors 72c and 72d, that is, a point on the X axis corresponding to substantially the same arrangement as the plurality of detection points of the multipoint AF systems (90a and 90b), and this point will be referred to as a right measurement point hereinafter). Next, as shown in fig. 18C, the main controller 20 converts the surface position information of the respective detected points of the multipoint AF systems (90a, 90b) into surface position data z1 to zk based on a straight line connecting the surface position of the left measurement point P1 and the surface position of the right measurement point P2. The main controller 20 performs the above conversion on all the information acquired at the time of sampling.

By obtaining the conversion data in advance as described above, the Z sensor 74 is used, for example, when exposure is performed_1，j、74_3，jAnd 76_1，q、76_2，qThe surface of wafer table WTB (formed with Y scale 39Y)₂And a point on the area where the Y scale 39Y is formed₁Point on the area) of the wafer table WTB, the tilt (mainly θ y rotation) of the Z position of the wafer table WTB with respect to the XY plane is calculated. By using the calculated Z position of wafer table WTB, the inclination (mainly rotation of θ y) with respect to the XY plane, and the surface position data Z1 to zk,the surface position on the wafer W can be controlled without actually acquiring the surface position information of the wafer surface. Therefore, since no problem occurs even when the multipoint AF system is disposed at a position away from the projection optical system PL, the multipoint AF system can be suitably applied to the focus map of the present embodiment even in an exposure apparatus having a narrow working distance.

In the above description, the surface position of the left measurement point P1 and the surface position of the right measurement point P2 are calculated from the average value of the measurement values of the Z sensors 72a and 72b and the average value of the measurement values of the Z sensors 72c and 72d, respectively, but the present invention is not limited to this, and the surface position information at the detection points of the multi-point AF systems (90a and 90b) may be converted into surface position data based on, for example, a straight line connecting the surface positions measured by the Z sensors 72a and 72 c. At this time, the difference between the measurement value of the Z sensor 72a and the measurement value of the Z sensor 72b acquired at each sampling time and the difference between the measurement value of the Z sensor 72c and the measurement value of the Z sensor 72d are obtained in advance. Subsequently, when surface position control is performed during exposure or the like, the Z sensor 74 is used _1，j、74_2，jAnd 76_1， _q、76_2，qThe surface of wafer table WTB is measured, the tilt of the Z position of wafer table WTB with respect to the XY plane (including not only the θ y rotation but also the θ x rotation) is calculated, and the surface position of wafer W can be controlled without actually obtaining the surface position information of the wafer surface by using the calculated Z position of wafer table WTB, the tilt with respect to the XY plane, the surface position data Z1 to zk, and the difference.

The above description is based on the premise that there is no unevenness on the surface of wafer table WTB. However, in reality, as shown in fig. 18(C), a Y scale 39Y is formed on the surface of the wafer WTB₂1 st partial region 28b₁And formed with a Y scale 39Y₁2 nd sub-area 28b₂Has irregularities on the surface thereof. However, even when the surface of wafer table WTB has irregularities as described above, the surface position control can be performed with extremely high accuracy at a point on the meridian line of wafer W (a straight line parallel to the Y axis passing through the center of the wafer).

This point will be explained below.

When performing the focus map, Z sensors 72a to 72d as references at the time of matching detect surface position information of a certain position (XY coordinate position) on the surface of wafer table WTB. As is clear from the above description, the X position of wafer stage WST is fixed, and focus mapping is performed while wafer stage WST is moved linearly in the + Y direction. That is, the lines (on the surface of the 2 nd hydrophobic plate 28 b) on which the Z sensors 72a to 72d detect the surface position information at the time of focus mapping are also straight lines parallel to the Y axis.

When performing this focus mapping (when wafer stage WST is moved in the + Y direction), the irradiation region located on the meridian line of the wafer is disposed at the exposure position (below projection optical system PL) without moving wafer stage WST in the X-axis direction. When the irradiated region of the meridian reaches the exposure position, it is located on a straight line parallel to the same Y axis as the Z sensors 72a and 72b and parallel to the pair of Z sensors 74_1，4、74_2，4A pair of Z sensors 76 on the same Y-axis line as the Z sensors 72c and 72d_1，3、76_2，3The surface position information of the same point on wafer table WTB at which Z sensors 72a and 72b and Z sensors 72c and 72d respectively detect the surface position information at the time of focus mapping is detected. That is, the reference surface measured by the Z sensor as the surface position information detection reference of the multipoint AF system (90a, 90b) is the same at the time of focus mapping as at the time of exposure. Therefore, even if unevenness or undulation occurs on the surface of wafer table WTB, the Z position obtained in the focus image can be used as the Z position without considering the unevenness or undulation when exposing the irradiation region of the meridian, and the focus of the wafer can be controlled during exposure, so that high-precision focus control can be performed.

When an irradiation region other than the meridians is exposed, the focus control accuracy is ensured to the same extent as that of the irradiation region of the meridians when there is no unevenness, undulation, or the like on the surface of wafer table WTB, but the focus control accuracy depends on the accuracy of the wire Z movement correction described later when there is unevenness, undulation, or the like on the surface of wafer table WTB. Further, when main controller 20 moves wafer stage WST in the X-axis direction, for example, to expose an irradiation region other than the meridian, the measurement values continue between the plurality of Z sensors as wafer stage WST moves.

The focus correction will be described next. The focus correction means performing the following two processes: the first half of the focus correction is to determine the relationship between the surface position information of one side and the other side of wafer table WTB in the X-axis direction in a certain reference state and the detection result (surface position information) of the representative detection point of the surface of measurement plate 30 by the multipoint AF system (90a, 90 b); and a second half of focus correction, in which surface position information of one side and the other side of wafer table WTB in the X-axis direction, corresponding to the best focus position of projection optical system PL detected by aerial image measuring device 45, is obtained in the same state as the reference state, and the offset of the representative detection point of multi-point AF systems (90a, 90b), that is, the deviation between the best focus position of projection optical system PL and the detection origin of the multi-point AF system, is obtained from the processing results of the two processes.

When this focus correction is performed, the main controller 20 is caused to face the X scales 39X, respectively, as shown in fig. 19(a)₁、39X₂Two X read heads 66(X linear encoders 70B, 70D) and a pair of Y scales 39Y facing each other₁、39Y₂Two Y read heads 64Y₂、64y₁(Y linear encoders 70A, 70C) to manage the position of wafer table WTB in the XY plane. In the state of fig. 19(a), the center line of wafer table WTB coincides with straight line LV. In the state of fig. 19 a, wafer table WTB is located at a position where the detection beam from multipoint AF systems (90a, 90b) is irradiated on measurement plate 30 in the Y-axis direction. Although not shown here, measurement stage MST is located on the + Y side of wafer table WTB (wafer stage WST), and water is held between CD bar 46 and wafer table WTB and front end lens 191 of projection optical system PL (see fig. 31).

(a) In this state, the main control device 20 performs the first half of the focus correction as described below. That is, main controller 20 detects surface position information of the surface of measurement plate 30 (see fig. 3) using the multi-spot AF system (90a, 90b) with reference to surface position information of wafer table WTB detected by Z sensors 72a, 72b, 72c, and 72d located in the vicinity of detection points at both ends of the detection area of the multi-spot AF system (90a, 90b) on one side and the other side in the X-axis direction. Thus, the relationship between the measurement values of Z sensors 72a, 72b, 72c, and 72d (surface position information of one side and the other side of wafer table WTB in the X-axis direction) in a state where the center line of wafer table WTB coincides with straight line LV, and the detection result (surface position information) of the detection point (the detection point located at the center or in the vicinity thereof among the plurality of detection points) on the surface of measurement plate 30 by the multipoint AF system (90a, 90b) is obtained.

(b) Next, main controller 20 moves wafer stage WST by a predetermined distance in the + Y direction, and stops wafer stage WST when measurement plate 30 is arranged at a position directly below projection optical system PL. Next, the main control device 20 performs the second half of the focus correction as described below. That is, main controller 20 measures surface position information of wafer table WTB on one side and the other side in the X-axis direction by a pair of Z sensors 74, as shown in fig. 19(B)_1， ₄、74_2，4、76_1，3、76_2，3The measured surface position information is used as a reference, and the position (Z position) of measurement plate 30 (wafer table WTB) in the optical axis direction of projection optical system PL is controlled, and an aerial image of a measurement mark formed on reticle R or a not-shown mark plate formed on reticle stage RST is measured by a slit scanning method using aerial image measuring apparatus 45, and the best focus position of projection optical system PL is measured based on the measurement result. At this time, as shown in fig. 19B, since the liquid immersion area 14 is formed between the projection optical system PL and the measurement plate 30 (wafer table WTB), the aerial image is measured through the projection optical system PL and water. Although not shown in fig. 19B, measurement board 30 of aerial image measuring apparatus 45 is mounted on wafer stage WST (wafer table WTB) and a light receiving element And so on, on measurement stage MST, the measurement of the aerial image is performed while keeping the wafer stage WST and measurement stage MST in contact with each other (or in a contact state) (see fig. 33). By the above measurement, Z sensor 74 is obtained in a state where the center line of wafer table WTB coincides with straight line LV_1，4、74_2，4、76_1，3、76_2，3(i.e., surface position information of one side and the other side of wafer table WTB in the X-axis direction). This measurement value corresponds to the best focus position of the projection optical system PL.

(c) Thus, main control device 20 can determine the relationship between the measurement values of Z sensors 72a, 72b, 72c, and 72d (surface position information of wafer table WTB on one side and the other side in the X-axis direction) obtained in the first half of the focus correction in (a) above, the detection result (surface position information) of the surface of measurement plate 30 by the multipoint AF system (90a, 90b), and Z sensor 74 corresponding to the best focus position of projection optical system PL obtained in the second half of the focus correction in (b) above_1，4、74_2，4、76_1，3、76_2，3(i.e., the surface position information of the end of wafer table WTB on one side and the other side in the X-axis direction), the offset of the representative detection point of the multipoint AF system (90a, 90b), that is, the deviation between the best focus position of projection optical system PL and the detection origin of the multipoint AF system is obtained. In the present embodiment, the representative detection point is, for example, a detection point at or near the center of the plurality of detection points, but the number and/or position thereof may be arbitrary. At this time, the main controller 20 adjusts the detection origin of the multipoint AF system so that the offset of the representative detection point becomes zero. This adjustment can be performed optically by adjusting the angle of a not-shown parallel plane plate inside the light receiving system 90b, or can be performed electrically by adjusting the detection bias. In addition, the offset may be stored in advance without adjusting the detection origin. The adjustment of the detection origin is performed here by the above-described optical method. This completes the focus correction of the multi-point AF systems (90a, 90 b). In addition, since it is not easy to make the offset of the remaining detection points other than the representative detection point zero in the adjustment of the detection origin by the optical system, the remaining detection points are not easily set to zero The dots are preferably stored with the offset optically adjusted.

Next, offset correction of detection values between a plurality of light receiving elements (sensors) corresponding to a plurality of detection points of the multipoint AF system (90a, 90b) individually (hereinafter referred to as AF-sensor offset correction) will be described.

When performing the offset correction between the AF sensors, as shown in fig. 20 a, the main controller 20 irradiates the CD bar 46 having a predetermined reference plane with a detection beam from an irradiation system 90a of the multipoint AF system (90a, 90b), receives reflected light from the surface (reference plane) of the CD bar 46 at a light receiving system 90b of the multipoint AF system (90a, 90b), and then takes in an output signal from the light receiving system 90 b.

In this case, if the surface of the CD bar 46 is set to be parallel to the XY plane, the main control device 20 can obtain the relationship between the detection values (measurement values) of the plurality of sensors corresponding to the plurality of detection points, respectively, based on the output signals acquired as described above, and store the relationship in the memory, or electrically adjust the detection offsets of the respective sensors so that the detection values of all the sensors become the same value as the detection value of the sensor corresponding to the representative detection point at the time of the focus correction, for example, thereby performing the offset correction between the AF sensors.

However, in the present embodiment, when the output signal from the light receiving system 90b of the multipoint AF system (90a, 90b) is received, the main control device 20 detects the inclination of the surface of the CD bar 46 by using the Z sensors 72a, 72b, 72c, 72d as shown in fig. 20 a, and therefore, it is not necessary to set the surface of the CD bar 46 to be parallel to the XY plane. That is, as shown in the schematic diagram of fig. 20(B), the detection values at the respective detection points may be set to values indicated by arrows in the diagram, that is, when the line connecting the upper ends of the detection values has irregularities indicated by broken lines in the diagram, the line connecting the upper ends of the detection values may be set to the solid line shown in the diagram.

Next, the movement correction of the lead Z for obtaining the correction information for correcting the influence of the unevenness of the surface of the wafer table WTB, more precisely, the surface of the 2 nd hydrophobic plate 28b in the X-axis direction will be described. Here, the wire Z movement correction is performed by taking in the measured value of the Z sensor that detects the surface position information of the left and right areas of the surface of the 2 nd hydrophobic plate 28b of wafer table WTB and the detected value of the surface position information of the wafer by the multipoint AF system at a predetermined sampling interval while moving wafer table WTB in the X-axis direction.

When this lead wire Z movement correction is performed, the main controller 20, similarly to the above-described focus map, as shown in fig. 21(a), respectively faces the X scales 39X₁、39X₂Two X read heads 66(X linear encoders 70B, 70D) and a pair of Y scales 39Y facing each other₁、39Y₂Two Y read heads 64Y₂、64y₁(Y linear encoders 70A, 70C) to manage the position of wafer table WTB in the XY plane. In the state of fig. 21 a, the center line of wafer table WTB is located on the + Y side of straight line LV, and main controller 20 measures surface position information of points in the vicinity of the-X-side end of the left and right areas on the surface of 2 nd hydrophobic plate 28b of wafer table WTB using Z sensors 72a, 72b, 72c, and 72d, and detects surface position information of the wafer using a multi-spot AF system (90a, 90 b).

Next, main controller 20 moves wafer stage WST in the-Y direction at a predetermined speed, as indicated by the white arrow in fig. 21 (a). During this movement, the main controller 20 repeatedly performs an operation of simultaneously taking in the measurement values of the Z sensors 72a and 72b and the measurement values of the Z sensors 72c and 72d and the multipoint AF systems (90a and 90b) at predetermined sampling intervals. Next, as shown in fig. 21(B), the operation is terminated at the time when the simultaneous capturing operation is terminated in a state where the Z sensors 72a and 72B and the Z sensors 72c and 72d are opposed to points in the vicinity of the + X-side end of the left and right regions on the surface of the 2 nd hydrophobic plate 28B of the wafer table WTB.

Next, the main controller 20 obtains the relationship between the surface position information at each detection point of the multi-point AF system (90a, 90b) and the surface position information of the Z sensors 72a to 72d captured simultaneously. Next, the unevenness of the surface of the 2 nd water-repellent plate 28b in the X-axis direction was calculated from a plurality of relationships obtained when different sampling was performed. That is, since the multi-spot AF system (90a, 90b) adjusts the inter-sensor offset at this time, the detection values of the sensors corresponding to any one of the detection points should be the same value as long as they are the same point on the surface of the 2 nd hydrophobic plate 28 b. Therefore, the difference in the detection values when the same point on the surface of the 2 nd hydrophobic plate 28b is detected by the sensors corresponding to the different detection points directly reflects the unevenness on the surface of the 2 nd hydrophobic plate 28b and the positional variation of the wafer stage in the Z-axis direction when the wafer stage moves. Therefore, by using this relationship, the unevenness of the surface of the 2 nd hydrophobic plate 28b in the X-axis direction is obtained from a plurality of relationships obtained when different sampling is performed.

As described above, main controller 20 obtains information on positional variation in the Z-axis direction of the surface of wafer table WTB that occurs when wafer table WTB (wafer stage WST) moves in the X-axis direction (at different X positions) from the results sequentially detected using multipoint AF systems (90a, 90b) while moving wafer table WTB (wafer stage WST) in the X-axis direction. The main controller 20 adds this information as a correction amount when performing exposure, and performs focus control of the wafer W.

Next, a parallel processing operation using wafer stage WST and measurement stage MST in exposure apparatus 100 according to the present embodiment will be described with reference to fig. 22 to 36. In the following operation, the main control device 20 controls the opening and closing of the valves of the liquid supply device 5 and the liquid recovery device 6 of the local immersion device 8 in the manner described above, and fills the projection optical system PL with water on the emission surface side of the front end lens 191 as needed. In the following description, for the sake of easy understanding, the description about the control of the liquid supply device 5 and the liquid recovery device 6 is omitted. In the following description of the operation, although a plurality of drawings are used, the same reference numerals may be assigned to the same members in each drawing, and the same reference numerals may not be assigned in some cases. That is, the drawings are different in the number of symbols, but the same structure is used regardless of the presence or absence of any symbol in the drawings. This point is the same as that of each of the drawings used in the description so far.

Fig. 22 shows a state in which step-and-scan exposure is performed on wafer W on wafer stage WST (a batch of wafers (one batch of 25 or 50 wafers) is illustrated here). At this time, measurement stage MST moves following wafer stage WST while keeping a predetermined distance. Therefore, it is sufficient that the distance of movement of measurement stage MST after the end of exposure when moving to the contact state (or close state) with wafer stage WST is the same as the predetermined distance.

In this exposure, the main controller 20 is controlled to respectively face the X scales 39X₁、39X₂Two X read heads 66(X encoders 70B, 70D) shown in a circle frame in FIG. 22, and two X heads facing the Y scale 39Y₁、39Y₂The position of wafer table WTB (wafer stage WST) in the XY plane (including θ z rotation) is controlled by the measurement values of two Y heads 64(Y encoders 70A, 70C) shown in fig. 22 as a circle. Further, main controller 20 causes a pair of Z sensors 74 to be respectively opposed to one side and the other side in the X-axis direction of the front surface of wafer table WTB_1，j、74_2，j、76_1，q、76_2，qThe position of wafer table WTB in the Z-axis direction, and the θ y rotation (roll) and the θ x rotation (pitch) are controlled. In addition, the position of wafer table WTB in the Z-axis direction and the θ y rotation (roll) are based on Z sensor 74_1，j、74_2，j、76_1，q、76_2，qAnd thetax rotation (pitch) may also be controlled based on the measurements of the Y-axis interferometer 16. In any case, during this exposure, control of the position of wafer table WTB in the Z-axis direction, θ y rotation, and θ x rotation (focus leveling control of wafer W) is performed based on the result of the focus map performed in advance.

In order to prevent wafer stage WST and measurement stage MST from approaching a predetermined distance during this exposure, shutters 49A and 49B are set in a state of closing openings 51A and 51B.

By using the main control device 20, the wafer alignment systems AL1 and AL2 are adjusted according to the result of the wafer alignment (EGA) performed in advance₁～AL2₂By repeating the operation of directing wafer stage WST to each shot for making the wafer W have a new baselineThe exposure operation is performed by an inter-shot movement operation in which a scanning start position (acceleration start position) of shot region exposure is moved, and a pattern scanning exposure operation in which a pattern formed on the reticle R is transferred to each shot region by a scanning exposure method. The exposure operation is performed with water held between the front end lens 191 and the wafer W. In addition, the irradiation region located on the-Y side to the irradiation region located on the + Y side in fig. 22 are performed in this order.

The main controller 20 may store the measurement values of the encoders 70A to 70D and the measurement values of the interferometers 16 and 126 during exposure, and update the correction map as necessary.

Next, as shown in fig. 23, when exposing different irradiation areas on the wafer W sequentially before the exposure of the wafer W is completed, for example, before exposing the final irradiation area, the main controller 20 lowers the shutters 49A and 49B via the driving mechanisms 34A and 34B to set the openings 51A and 51B to the open state. After confirming that the shutters 49A and 49B are completely opened via the open/close sensor 101, the main controller 20 controls the stage drive system 124 based on the measurement value of the Y-axis interferometer 18 while maintaining the measurement value of the X-axis interferometer 130 at a constant value, and moves the measurement stage MST (measurement table MTB) to the position shown in fig. 24. At this time, the-Y side of CD lever 46 (measurement table MTB) comes into surface contact with the + Y side of wafer table WTB. Further, for example, the measurement values of an interferometer or an encoder for measuring the positions of the respective tables in the Y axis direction may be monitored, and the measurement table MTB and the wafer table WTB may be separated by about 300 μm in the Y axis direction to be kept in a non-contact state (close state).

Next, as shown in fig. 25, main controller 20 starts the operation of driving measurement stage MST in the-Y direction and driving wafer stage WST to unload position UP while maintaining the positional relationship between wafer table WTB and measurement table MTB in the Y-axis direction. When this operation starts, measurement stage MST moves only in the-Y direction in the present embodiment, and wafer stage WST moves in the-Y direction and the-X direction.

When wafer stage WST and measurement stage MST are simultaneously driven by main controller 20 in this manner, the water held between tip end lens 191 of projection unit PU and wafer W (water in liquid immersion area 14), that is, the water moves in the order of wafer W → plate body 28 → CD lever 46 → measurement table MTB as wafer stage WST and measurement stage MST move to the-Y side. In the movement, wafer table WTB and measurement table MTB are kept in the contact state (or in the proximity state). Fig. 25 shows a state immediately before water in the liquid immersion area 14 moves from the plate 28 to the CD bar 46.

When wafer stage WST and measurement stage MST are further driven by a small distance in the-Y direction from the state of fig. 25, since Y encoders 70A and 70C cannot measure the position of wafer stage WST (wafer table WTB), main controller 20 switches the control of the Y position and θ z rotation of wafer stage WST (wafer table WTB) from the control based on the measurement values of Y encoders 70A and 70C to the control based on the measurement value of Y-axis interferometer 16. Next, after a predetermined time, since measurement stage MST reaches the position where Sec-BCHK (time interval) is performed as shown in fig. 26, main controller 120 stops measurement stage MST at the position and passes through X scale 39X ₁While X reading head 66(X linear encoder 70B) shown in a circle in fig. 26 facing thereto measures the X position of wafer stage WST, measures the Y position, θ z rotation, and the like with Y-axis interferometer 16, wafer stage WST is driven further to unload position UP and stopped at unload position UP. In the state of fig. 26, water is held between measuring table MTB and tip lens 191.

Next, as shown in fig. 26 and 27, main controller 20 measures the relative positions of the four second alignment systems with respect to first alignment system AL1 using CD lever 46 of measurement stage MST in the above-described procedure. And Sec-BCHK (time interval) was performed. In parallel with this Sec-BCHK (time interval), main controller 20 gives a command to a drive system of an unillustrated unloading arm to unload wafer W on wafer stage WST stopped at unloading position UP, raises vertical moving pins CT (not shown in fig. 26, see fig. 27) driven to rise by a predetermined amount during unloading, and drives wafer stage WST in the + X direction to move to loading position LP. Here, the wafer unloading operation is performed by supporting and lifting the wafer W from below with the up-and-down pins CT, entering the unloading arm from below the wafer W, and then transferring the wafer to the unloading arm from the up-and-down pins CT by slightly moving the up-and-down pins CT downward or slightly lifting the unloading arm upward.

Next, as shown in fig. 28, main controller 20 moves measurement stage MST to an optimum standby position (hereinafter referred to as "optimum scram standby position") at which measurement stage MST is moved from a state of being separated from wafer stage WST to the contact state (or close state) with wafer stage WST, and closes shutters 49A and 49B in the steps described above. In parallel with this, the main control device 20 gives an instruction to a drive system of a loading arm, not shown, to load a new wafer W onto the wafer table WTB. The wafer W loading operation is performed by transferring the wafer W held by the loading arm from the loading arm to the up-and-down moving pin CT which is kept in an elevated state by a predetermined amount, and after the loading arm is removed, the up-and-down moving pin CT is lowered to load the wafer W on the wafer holder, and then the wafer W is sucked by a vacuum chuck not shown. At this time, since the vertical movement pins CT are maintained in a state of being raised by a predetermined amount, the wafer loading operation can be performed in a shorter time as compared with the case where the vertical movement pins CT are lowered and driven to be accommodated in the wafer holder. Fig. 28 shows a state in which the wafer W is mounted on the wafer table WTB.

In the present embodiment, the optimum emergency stop standby position of measurement stage MST is appropriately set based on the Y coordinate of the alignment mark provided in the alignment irradiation region on the wafer. Thus, when the measurement stage MST is moved to the contact state (or the proximity state), since the operation of moving the measurement stage MST to the optimal scram waiting position is not required, the number of times of moving the measurement stage MST at one time can be reduced as compared with the case where the measurement stage MST is caused to wait at a position away from the optimal scram waiting position. In the present embodiment, the optimum emergency stop standby position is set to a position at which wafer stage WST can be stopped at a position at which the wafer alignment is performed and can be moved to the contact state (or the proximity state).

Next, as shown in fig. 29, main controller 20 moves wafer stage WST from loading position LP to a position where fiducial marks FM on measurement plate 30 are positioned within the field of view (detection area) of first alignment system AL1 (i.e., a position where the first half of the Pri-BCHK process described above is performed). During this movement, main controller 20 switches the control of the position of wafer table WTB in the XY plane from the control based on the measurement value of encoder 70B (X-axis direction) and the control based on the measurement value of Y-axis interferometer 16 (Y-axis direction and θ z rotation) to the control based on the measurement value facing X scale 39X₁、39X₂Two X read heads 66 (encoders 70B, 70D) shown in a circle frame in FIG. 29, and a Y scale 39Y facing the Y scale₁、39Y₂Two Y read heads 64Y shown in circled frame in FIG. 29₂、64y₁Control of the measured values of (encoders 70A, 70C).

Subsequently, the main controller 20 performs the former half of the aforementioned Pri-BCHK process of detecting the reference marks FM using the first alignment system AL 1. At this time, measurement stage MST is waiting at the optimum scram position.

Next, main control device 20 starts moving wafer stage WST in the + Y direction to a position for detecting alignment marks (attached to the three first irradiation regions AS (see fig. 12C)) while managing the position of wafer stage WST based on the measurement values of the four encoders, after the start of movement of wafer stage WST in the + Y direction, main control device 20 opens shutters 49A and 49B in the above-described procedure so that wafer stage WST and measurement stage MST can be brought closer together, and main control device 20 confirms that shutters 49A and 49B are opened based on the detection result of open/close sensor 101.

Next, when wafer stage WST reaches the position shown in fig. 30, main control device 20 detects contact (or proximity to a distance of about 300 μm) between wafer stage WST and measurement stage MST based on the outputs of impact detection sensors 43B and 43C, and immediately stops wafer stage WST. Before that, main controller 20 operates (turns on) Z sensors 72a to 72d at or before the time when all or a part of Z sensors 72a to 72d face wafer table WTB to start measurement of the Z position and tilt (θ y rotation and θ x rotation) of wafer table WTB.

After wafer stage WST stops, main control apparatus 20 uses first alignment system AL1 and second alignment system AL2₂、AL2₃Alignment marks (see the star marks in fig. 30) attached to the three first alignment shot areas AS are detected substantially simultaneously and independently, and the three alignment systems AL1 are used₁、AL2₂、AL2₃The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other. In the simultaneous detection operation of the alignment marks attached to the three first alignment irradiation areas AS, the plurality of alignment systems AL1 and AL2 are changed while changing the Z position of wafer table WTB AS described above ₁～AL2₄Relative to the wafer W mounted on the wafer table WTB in the Z-axis direction (focusing direction).

AS described above, in the present embodiment, when the position of the alignment mark of the first alignment irradiation area AS is detected, the movement to the contact state (or the proximity state) of measurement stage MST and wafer stage WST is terminated, and the movement of both stages WST and MST in the contact state (or the proximity state) in the + Y direction from the above-described position is started by main control device 20 (the step movement is performed before the above-described position for detecting the alignment mark attached to the five second alignment irradiation areas AS). Before starting the movement of both stages WST and MST in the + Y direction, main controller 20 starts irradiation of wafer table WTB with the detection beams of multipoint AF systems (90a and 90b) as shown in fig. 30. Thereby forming a detection area of the multipoint AF system on wafer table WTB.

Next, when both stages WST and MST reach the positions shown in fig. 31 while both stages WST and MST move in the + Y direction, main control device 20 performs the first half of the focus correction described above, and obtains the relationship between the measurement values of Z sensors 72a, 72b, 72c, and 72d (surface position information of one side and the other side of wafer table WTB in the X-axis direction) and the detection result (surface position information) of the surface of measurement plate 30 by the multipoint AF system (90a and 90b) in a state where the center line of wafer table WTB coincides with straight line LV. At this time, liquid immersion area 14 is formed near the boundary between CD bar 46 and wafer table WTB. That is, the water in the liquid immersion area 14 is in a state immediately before being transferred from the CD bar 46 to the wafer table WTB.

Next, when the two stages WST and MST are further moved in the + Y direction while maintaining the contact state (or the close state) and reach the positions shown in fig. 32, the five alignment systems AL1 and AL2 are used₁～AL2₄The alignment marks (see the star marks in fig. 32) attached to the five second alignment irradiation regions AS are detected substantially simultaneously and independently, and the five alignment systems AL1 and AL2 are used₁～AL2₄The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other. At this time, the simultaneous detection operation of the alignment marks attached to the five second alignment irradiation areas AS is also performed while changing the Z position of wafer table WTB AS described above.

In addition, at this time, since there is no X scale 39X₁An X-ray head facing and positioned on the straight line LV, so that the main control device 20 can read the X-ray scale 39X₂The measurement values of the opposing X read head 66(Y linear encoder 70D) and Y linear encoders 70A, 70C control the position of wafer table WTB in the XY plane.

AS described above, in the present embodiment, position information (two-dimensional position information) of eight alignment marks in total can be detected at the time point when the detection of the alignment marks in the second alignment irradiation area AS is completed. Therefore, at this stage, the main controller 20 may calculate a scale (irradiation magnification) of the wafer W by performing statistical calculation using the position information, for example, the EGA method, and adjust the optical characteristics of the projection optical system PL, for example, the projection magnification, based on the calculated irradiation magnification. In the present embodiment, the specific movable lens constituting the projection optical system PL can be driven or changed The optical characteristics of the projection optical system PL are adjusted by varying the gas pressure inside the airtight chamber formed between the specific lenses constituting the projection optical system PL and controlling an adjusting device 68 (see fig. 8) for adjusting the optical characteristics of the projection optical system PL. That is, master control device 20 may also be aligned to systems AL1, AL2₁～AL2₄After a predetermined number (eight here) of marks on the wafer W are detected, the adjusting device 68 is controlled based on the detection results to adjust the optical characteristics of the projection optical system PL. The number of marks is not limited to eight, half of the total number of marks to be detected, or the like, and may be equal to or more than the number necessary for calculating a scale or the like of a wafer.

After the simultaneous detection operation of the alignment marks provided in the five second alignment irradiation areas AS is completed, the main controller 20 resumes the movement of the two stages WST and MST in the contact state (or the proximity state) in the + Y direction, and starts the above-described focus map using the Z sensors 72a to 72d and the multipoint AF systems (90a and 90b), AS shown in fig. 32.

Next, when both stages WST and MST reach the position where measurement plate 30 is disposed directly below projection optical system PL shown in fig. 33, main controller 20 performs the second half of the foregoing Pri-BCHK processing and the second half of the foregoing focus correction processing.

Next, the main controller 20 calculates a baseline of the first alignment system AL1 from the results of the former half of the Pri-BCHK process and the latter half of the Pri-BCHK process. Meanwhile, main control device 20 calculates the relationship between the measurement values of Z sensors 72a, 72b, 72c, and 72d (surface position information of wafer table WTB at one side and the other side in the X-axis direction) obtained in the first half of the focus correction process and the detection result (surface position information) of the surface of measurement plate 30 by the multi-spot AF system (90a and 90b), and calculates Z sensor 74 corresponding to the best focus position of projection optical system PL obtained in the second half of the focus correction process_1，4、74_2，4Z sensor 76_1，3、76_2，3The measured value (i.e., the surface position of the wafer table WTB at one side and the other side in the X-axis directionInformation) of the detected point, and the offset of the representative detected point of the multipoint AF system (90a, 90b) is obtained, and the detection origin of the multipoint AF system is adjusted to zero by the optical method.

In this case, from the viewpoint of throughput, only one of the latter half processing of the Pri-BCHK and the latter half processing of the focus correction may be performed, or the process may be shifted to the next processing without performing both processing. Of course, the main controller 20 may move the wafer stage WST to a position where the alignment mark provided on the first alignment irradiation area AS can be detected from the loading position LP, without performing the second half of the Pri-BCHK and without performing the first half of the Pri-BCHK.

In the state of fig. 33, the focus map is continued.

When both stages WST and MST in the contact state (or the close state) are moved in the + Y direction to reach the position shown in fig. 34, main control device 20 stops wafer stage WST at the position and continues to move measurement stage MST in the + Y direction. Next, the master control device 20 uses five alignment systems AL1, AL2₁～AL2₄The alignment marks (see the star marks in fig. 34) attached to the five third alignment irradiation regions AS are detected substantially simultaneously and independently, and the five alignment systems AL1 and AL2 are used₁～AL2₄The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other. At this time, the simultaneous detection operation of the alignment marks attached to the five third alignment irradiation areas AS is also performed while changing the Z position of wafer table WTB AS described above. In addition, the focus mapping is continued at this point as well.

On the other hand, after a predetermined time has elapsed from the stop of wafer stage WST, dampers 47A and 47B are disengaged from openings 51A and 51B formed in X-axis fixture 80, and measurement stage MST and wafer stage WST move from the contact (or close) state to the separated state. After moving to the separated state, main control device 20 raises and drives shutters 49A and 49B via drive mechanisms 34A and 34B to set the state of closing openings 51A and 51B, and stops at the exposure start standby position where measurement stage MST waits until the exposure start.

Next, main controller 20 moves wafer stage WST in the + Y direction to the detection positions of the alignment marks attached to the three first alignment irradiation areas AS. The focus mapping is continued at this point. On the other hand, wafer stage WST stands by at the exposure start standby position.

Next, when wafer stage WST reaches the position shown in fig. 35, main control apparatus 20 immediately stops wafer stage WST and uses first alignment system AL1 and second alignment system AL2₂、AL2₃Alignment marks (see the star marks in fig. 35) attached to the three first alignment shot regions AS on the wafer W are detected substantially simultaneously and independently, and the three alignment systems AL1 and AL2 are used₂、AL2₃The detection result of (a) and the measured values of the four encoders at the time of the detection are stored in a memory, not shown, in such a manner as to be correlated with each other. At this time, the simultaneous detection operation of the alignment marks attached to the three first alignment irradiation areas AS is also performed while changing the Z position of wafer table WTB AS described above. At this time, focus mapping is continued, and measurement stage MST is kept waiting at the exposure start waiting position. Next, the main controller 20 calculates the arrangement information (coordinate values) of all the irradiated regions on the wafer W on the XY coordinate system defined by the measurement axes of the four encoders by performing a statistical operation using the detection results of the sixteen alignment marks obtained in the above manner and the measurement values of the corresponding four encoders by the EGA method, for example.

Next, main controller 20 continues the focus mapping while moving wafer stage WST in the + Y direction again. Next, when the detection light beams from the multi-spot AF systems (90a, 90b) deviate from the surface of the wafer W, the focus map is terminated as shown in fig. 36. Thereafter, mainlyThe control device 20 is based on the results of the wafer alignment (EGA) and the five alignment systems AL1, AL2₁～AL2₂The latest baseline measurement result and the like are obtained by performing step-and-scan exposure by immersion exposure, and sequentially transferring the reticle pattern to a plurality of shot areas on the wafer W. Thereafter, the same operation is repeated for the remaining wafers in the lot.

In addition, according to the present embodiment, while wafer stage WST is moving linearly in the Y-axis direction, surface position information of the front surface of wafer W is detected by multipoint AF systems (90a, 90b) in which a plurality of detection points are set at predetermined intervals in the X-axis direction, and a plurality of alignment systems AL1, AL2 in which detection areas are aligned in a line in the X-axis direction₁～AL2₄To detect alignment marks whose positions on the wafer W are different from each other. That is, wafer stage WST (wafer W) passes only linearly through the plurality of detection points (detection areas AF) of multipoint AF systems (90a, 90b) and the plurality of alignment systems AL1, AL2 ₁～AL2₄Since the detection of the surface position information of the substantially entire surface of the wafer W and the detection of all alignment marks to be detected on the wafer W (for example, the alignment marks of the alignment irradiation region of the EGA) are completed in the detection region of (b), the throughput can be further improved as compared with a case where the detection operation of the alignment marks and the detection operation of the surface position information (focus information) are performed without being related to each other (independently).

In the present embodiment, as is apparent from the above description of the parallel processing operation using wafer stage WST and measurement stage MST, main controller 20 uses a plurality of alignment systems AL1 and AL2 during the movement of wafer stage WST from the loading position to the exposure position (exposure area IA) (i.e., during the movement of wafer stage WST in the Y-axis direction)₁～AL2₄A plurality of marks (alignment marks for aligning the irradiation region) having different positions in the X-axis direction on wafer W are simultaneously detected, and surface position information of wafer W passing through the detection regions of the plurality of alignment systems as wafer stage WST moves in the Y-axis direction is detected by multipoint AF systems (90a, 90 b). Therefore, the detection operation of the alignment mark and the surface position information (focus information) are performed without correlation) The processing capability can be further improved compared with the case of detecting the motion. In the present embodiment, the loading position and the exposure position are different in the X-axis direction, but may be the same in the X-axis direction. At this time, wafer stage WST can be moved substantially in a straight line from the loading position to the detection area of the alignment system (and the multipoint AF system). In addition, the loading position and the unloading position may be the same position.

In addition, according to the present embodiment, the pair of Y scales 39Y can be respectively opposed to each other while being aligned with each other₁、39Y₂A pair of Y read heads 64Y₂、64y₁The measurement values (of a pair of Y-axis linear encoders 70A and 70C) are measured to move wafer table WTB (wafer stage WST) in the Y-axis direction while measuring the position of wafer table WTB (wafer stage WST) in the Y-axis direction and the rotation (yaw) θ z. In this case, the second alignment system AL2 can be adjusted in the arrangement (size, etc.) of the irradiation regions already formed on the wafer W₁～AL2₄Since movement of wafer table WTB (wafer stage WST) in the Y-axis direction is realized in a state of a relative position in the X-axis direction with respect to first alignment system AL1, a plurality of alignment systems AL1 and AL2 can be used₁～AL2₄The alignment marks of a plurality of irradiation regions (for example, alignment irradiation regions) on the wafer W at the same position in the Y-axis direction and at different positions in the X-axis direction are measured at the same time.

In addition, according to the present embodiment, main control device 20 can use alignment systems AL1 and AL2 while controlling the position of wafer table WTB (wafer stage WST) based on the measurement values of encoder systems (Y linear encoders 70A and 70C and X linear encoders 70B and 70D)₁～AL2₄To detect the alignment marks on the wafer W. That is, the two scales can be respectively opposite to the Y scale 39Y ₁、39Y₂Y read heads 64(Y linear encoders 70A, 70C) and X scales 39X and 70X, respectively₁、39X₂Using alignment systems AL1 and AL2, the position of wafer table WTB (wafer stage WST) is controlled with high accuracy by the measurement values of X read head 66(X linear encoders 70B and 70D) of (B)₁～AL2₄To detect alignment on the wafer WAnd (4) marking.

In addition, according to the present embodiment, alignment systems AL1 and AL2 are set to follow the difference in position of wafer table WTB (wafer stage WST) in the XY plane₁～AL2₄Since the number of detection dots (number of measurement dots) of the alignment marks on wafer W to be simultaneously detected is different, for example, when wafer table WTB (wafer stage WST) is moved in a direction intersecting the X axis, for example, in the Y axis direction, for example, at the time of performing the above-described wafer alignment, a desired number of alignment systems can be used to simultaneously detect alignment marks having different positions on wafer W, based on the position of wafer table WTB (wafer stage WST) in the Y axis direction, in other words, based on the arrangement (LAYOUT) of the irradiation regions on wafer W.

In addition, according to the present embodiment, the main controller 20 may control the adjusting device 68 to adjust the optical characteristics of the projection optical system PL based on the detection results of a plurality of (for example, eight) alignment marks on the wafer W detected by the alignment system up to now, at a stage when the alignment mark to be detected by the alignment system remains on the wafer W (for example, at the time when the detection of the alignment mark attached to the second alignment irradiation area AS is completed). In this case, even if the image of the measurement mark is displaced in accordance with the adjustment after the adjustment of the optical characteristics of the projection optical system PL, for example, when the detection of the image of the predetermined measurement mark (or pattern) of the projection optical system PL is performed, the image of the measurement mark after the displacement is measured, and as a result, the displacement of the image of the measurement mark in accordance with the adjustment of the optical characteristics of the projection optical system PL does not become a factor of the measurement error. Further, since the adjustment is started based on the detection result of the alignment mark detected up to now before all the alignment marks to be detected are detected, the adjustment can be performed simultaneously with the detection operation of the remaining alignment marks. That is, in the present embodiment, the time required for the adjustment can be made to overlap with the time from the start of the detection of the alignment mark in the third alignment irradiation area AS to the end of the detection of the alignment mark in the first alignment irradiation area AS. This can improve the throughput compared with the conventional technique in which the adjustment is started after all the marks have been detected.

Further, according to the present embodiment, the main controller 20 performs the alignment systems AL1 and AL2 during a period from the start of an operation (for example, the first half of the Pri-BCHK processing) for measuring the positional relationship between the projection position of the pattern (for example, the pattern of the reticle R) image of the projection optical system PL and the detection center of the alignment system AL1 (the base line of the alignment system AL 1) to the end of the operation (for example, the period from the end of the second half of the Pri-BCHK processing), and then performs the alignment systems AL1 and AL2₁～AL2₄The detection of the alignment marks on the wafer W (e.g., the alignment marks of the three first alignment shot areas and the five second alignment shot areas) is performed. That is, at least a part of the detection operation of the alignment system for the mark can be performed simultaneously with the measurement operation of the positional relationship. Therefore, at least a part of the detection operation of the alignment system for the plurality of alignment marks to be detected on the wafer W can be ended at the time when the measurement operation of the positional relationship is ended. This makes it possible to improve the throughput compared to the case where the detection operation of the plurality of alignment marks by the alignment system is performed before or after the measurement operation of the positional relationship.

In addition, according to the present embodiment, the main control device 20 controls the alignment systems AL1 and AL2 ₁～AL2₄During a period from the start of the detection operation of the plurality of alignment marks to be detected on the wafer W (for example, the wafer alignment operation described above, that is, the detection operation of the first alignment irradiation region AS to the total of sixteen alignment marks respectively attached to the first alignment irradiation region AS) to the end of the detection operation, the measurement operation of measuring the positional relationship between the projection position of the pattern image of the reticle R projected by the projection optical system PL and the detection center of the alignment system AL1 (the base line of the alignment system AL 1) is performed. That is, the measurement operation of the positional relationship can be performed simultaneously with a part of the detection operation of the mark by the alignment system. Therefore, the alignment systems AL1 and AL2 can be performed₁～AL2₄The measurement operation of the positional relationship is terminated during the detection operation of the plurality of alignment marks to be detected on the wafer W. Thereby, the alignment system is aligned withThe throughput can be further improved as compared with the case where the above-described measurement operation of the positional relationship is performed before or after the detection operation of the plurality of alignment marks to be detected on the wafer W.

In addition, according to the present embodiment, main controller 20 performs a switching operation between a contact operation of wafer table WTB and measurement table MTB (or an approaching state in which the contact state is brought close to, for example, 300 μm or less) and a separation state in which the contact state and the separation state are separated, after starting a detection operation of a plurality of alignment marks to be detected on wafer W (for example, the detection operation of sixteen alignment marks, which is the aforementioned wafer alignment operation). In other words, according to the present embodiment, the detection operation of the alignment system for the plurality of alignment marks to be detected on the wafer W is started in the contact state (or the proximity state), and the two stages are controlled to switch from the contact state (or the proximity state) to the separation state before all the detection operations of the plurality of marks are finished. Therefore, the state switching operation can be terminated while the detection operation of the plurality of alignment marks to be detected on the wafer W is performed. This can improve the throughput compared to the case where the above-described switching operation is performed before or after the detection operation of the plurality of alignment marks to be detected on the wafer W.

In addition, according to the present embodiment, main control device 20 starts the baseline measurement operation of alignment system AL1 in the detached state, and ends the operation in the contact state (or proximity state).

In addition, according to the present embodiment, the stage driving system 124(Z leveling mechanism) and the alignment systems AL1 and AL2 are controlled by the main controller 20₁～AL2₄While the relative positional relationship between the plurality of alignment systems and the wafer W in the Z-axis direction (focus direction) is changed by a leveling mechanism (not shown), alignment marks having different positions on the wafer W are simultaneously detected by the corresponding plurality of alignment systems. In other words, while the relative positional relationship between the plurality of alignment systems and the wafer W in the focus direction is changed simultaneously by the plurality of alignment systems, the marks having different positions on the wafer W are detected simultaneously by the corresponding plurality of alignment systems. This makes it possible to detect the marks in each alignment system in, for example, the best focus state, and to detect the marks at different positions on the wafer W with good accuracy, with little influence of the irregularities on the surface of the wafer W and the difference in best focus among the plurality of alignment systems, by preferentially using the detection results. In addition, in the present embodiment, the alignment systems AL1, AL2 ₁～AL2₄Although the alignment system is arranged substantially along the X-axis direction, a method of simultaneously detecting marks having different positions on the wafer W by a plurality of corresponding alignment systems while simultaneously changing the relative positional relationship between the plurality of alignment systems and the wafer W in the focus direction by the plurality of alignment systems is effective even if the alignment system is different from the above arrangement. That is, it is sufficient that the marks at different positions formed on the wafer W can be detected substantially simultaneously by a plurality of alignment systems.

In addition, according to the present embodiment, the positional information of wafer table WTB in the XY plane can be measured with high accuracy without being affected by air shake or the like by the encoder system (including encoders 70A to 70D and the like having good short-term stability of the measurement values), and the positional information can be measured by the plane position measurement system (including Z sensors 72a to 72D, 74 and the like)_1，1～74_2，6And 76_1，1～76_2， ₆Etc.) to measure the positional information of wafer table WTB in the Z-axis direction orthogonal to the XY plane with high accuracy without being affected by air shake or the like. In this case, since both of the encoder system and the surface position measuring system can directly measure the upper surface of wafer table WTB, the position of wafer table WTB and hence the position of wafer W can be controlled easily and directly.

In addition, according to the present embodiment, when performing the focus matching, the main controller 20 causes the surface position measuring system and the multipoint AF systems (90a, 90b) to operate simultaneously, and converts the detection result of the multipoint AF systems (90a, 90b) into data based on the measurement result of the surface position measuring system. Therefore, by acquiring the conversion data in advance, it is only necessary to measure the positional information of the wafer table WT in the Z-axis direction and the positional information in the tilt direction with respect to the XY plane by the surface position measuring system thereafter, and the surface position of the wafer W can be controlled without acquiring the surface positional information of the wafer W. Therefore, in the present embodiment, even if the working distance between the front end lens 191 and the front surface of the wafer W is narrow, no problem occurs, and the focus/leveling control of the wafer W at the time of exposure can be performed with good accuracy.

In the present embodiment, as can be seen from the above description of the parallel processing operation using wafer stage WST and measurement stage MST, main control device 20 performs simultaneous operation of the surface position control system and the multipoint AF systems (90a, 90b) and conversion processing (focus matching) of the data described above, while wafer W is moving from a position (loading position LP) for carrying wafer W into wafer stage WST to a position for performing predetermined processing, for example, exposure (pattern formation) on wafer W.

In the present embodiment, the alignment systems AL1 and AL2 are started₁～AL2₄In the process from the detection operation of the plurality of marks to be detected (for example, the wafer alignment operation) to the completion of the detection operation of the plurality of wafers, the main controller 20 performs simultaneous operation of the surface position control system and the multi-spot AF system (90a, 90b) and starts the conversion processing of the data.

Further, according to the present embodiment, since the wafer table WTB, and further the surface position of the wafer W can be controlled with high accuracy as described above, high-accuracy exposure can be performed with little exposure failure due to an error in the surface position control, and thus a pattern image can be formed on the wafer W without causing image blur.

In addition, according to the present embodiment, main controller 20 can measure the surface position information of wafer W using the detection values (measurement values) of multipoint AF systems (90a, 90b) with reference to the surface position information of wafer table WTB on one side and the other side in the X axis direction, for example, before performing exposure, and can adjust the position of wafer W in the direction parallel to optical axis AX of projection optical system PL and in the direction inclined with respect to the surface orthogonal to optical axis AX with reference to the surface position information of wafer table WTB on one side and the other side in the X axis direction, also at the time of performing exposure. Therefore, the surface position of the wafer W can be accurately controlled even when the exposure is actually performed, regardless of whether the surface position information of the wafer W is measured before the exposure.

In addition, according to the present embodiment, aerial image measuring device 45 is provided with a part on wafer table WTB (wafer stage WST) and the remaining part on measurement stage MST, and measures an aerial image of a measurement mark formed by projection optical system PL. Therefore, for example, when performing the above-described focus correction, when measuring the best focus position of projection optical system PL, aerial image measuring device 45 is used to measure the position of wafer table WTB (wafer stage WST) provided with a part of aerial image measuring device 45 in the direction parallel to the optical axis of projection optical system PL as a reference of the best focus position. Therefore, when exposing a wafer with illumination light IL, the position of wafer table WTB (wafer stage WST) in the direction parallel to the optical axis of projection optical system PL can be adjusted with high accuracy based on the measurement result of the best focus position. Further, since only a part of aerial image measuring device 45 is provided in wafer table WTB (wafer stage WST), this positional controllability can be ensured satisfactorily without increasing the size of wafer table WTB (wafer stage WST). In addition, the remaining part of aerial image measuring device 45 may not be provided entirely on measurement stage MST, but may be provided separately on measurement stage MST and outside thereof.

In addition, according to the present embodiment, position information of measurement stage MST is measured by Y-axis interferometer 18 and X-axis interferometer 130, and position information of wafer table WTB (wafer stage WST) is measured by four linear encoders 70A to 70D. Here, the linear encoders 70A to 70D are reflection-type encoders including a plurality of gratings (that is, the Y scale 39Y) each having a grating disposed on the wafer table WTB and having a periodic direction in a direction parallel to the Y axis and the X axis, respectively₁、39Y₂Or X scale 39X₁、39X₂) And a scale 39Y₁、39Y₂、39X₁、39X₂A head (Y head 64 or X head 66) disposed opposite to each other. Therefore, the linear encoders 70A to 70D are less susceptible to air fluctuation because the optical path length of the light beam emitted from each of the heads to the opposing scale (grating) is much shorter than that of the Y-axis interferometer 18 and the X-axis interferometer 130, and the short-term stability of the measurement values is superior to that of the Y-axis interferometer 18 and the X-axis interferometer 130. Therefore, the position of wafer table WTB (wafer stage WST) for holding the wafer can be stably controlled.

In addition, according to the present embodiment, the intervals in the X-axis direction of the plurality of Y heads 64, which have the Y-axis direction as the measurement direction, are set to be larger than the Y scale 39Y₁、39Y₂The width in the X-axis direction is narrower, and the intervals in the Y-axis direction of the plurality of X-ray heads 66 with the X-axis direction as the measurement direction are set to be smaller than the X scale 39X ₁、39X₂The width in the Y-axis direction is narrow. Thus, when wafer table WTB (wafer stage WST) is moved, while sequentially switching a plurality of Y heads 64, the detection light (light beam) can be irradiated to Y scale 39Y according to the light used for the detection₁Or 39Y₂The Y linear encoder 70A or 70C measures the Y position of wafer table WTB (wafer stage WST), and simultaneously switches the plurality of X heads 66 in order, and irradiates the detection light (light beam) onto X scale 39X₁Or 39X₂To measure the X position of wafer table WTB (wafer stage WST).

In addition, according to the present embodiment, when the wafer stage (wafer stage WST) is moved in the Y-axis direction in order to acquire correction information of the grating pitch of the scale, the main control device 20 obtains the correction information for correcting each grating line 37 (constituting the X scale 39X) in the above-described procedure₁、39X₂) Correction information of the curvature of (raster curvature correction information). Then, main controller 20 simultaneously uses the Y-position information of wafer table WTB (wafer stage WST) and X scale 39X₁、39X₂The correction information of the raster curve (and the correction information of the raster pitch) of (a) correction of the measurement values obtained from the head units 62B and 62D is performed using the X scale 39X ₁、39X₂With the head units 62B, 62D toWafer table WTB (wafer stage WST) is driven in the X-axis direction. Therefore, the X scale 39X is not limited to be configured₁、39X₂Using an X scale 39X₁、39X₂Head units 62B and 62D (encoders 70B and 70D) drive wafer table WTB (wafer stage WST) in the X-axis direction with good accuracy. By performing the same operation as described above in the Y-axis direction, wafer table WTB (wafer stage WST) can be driven in the Y-axis direction with good accuracy.

In the case illustrated in the above embodiment, the pair of Y scales 39Y for measuring the position in the Y axis direction₁、39Y₂And a pair of X scales 39X for measuring the position in the X-axis direction₁、39X₂Provided on wafer table WTB, and in response thereto, a pair of head units 62A, 62C are disposed on one side and the other side in the X-axis direction via projection optical system PL, and two head units 62B, 62D are disposed on one side and the other side in the Y-axis direction via projection optical system PL. However, the present invention is not limited to this, and only the Y scale 39Y for measuring the Y-axis position may be used₁、39Y₂And an X scale 39X for measuring the position in the X-axis direction₁、39X₂At least one of the two units may be disposed on wafer table WTB (not a pair), or only one of the pair of head units 62A and 62C and at least one of the two head units 62B and 62D may be provided. The extending direction of the scale and the extending direction of the head unit are not limited to the orthogonal directions such as the X-axis direction and the Y-axis direction in the above embodiments, and may be directions intersecting each other.

In the above description, while Sec-BCHK (time interval) is performed using CD lever 46 of measurement stage MST during wafer exchange with wafer stage WST, the present invention is not limited to this, and at least one of uneven illuminance measurement (and illuminance measurement), aerial image measurement, wavefront aberration measurement, and the like may be performed using the measuring member of measurement stage MST, and the measurement result may be reflected in wafer exposure performed thereafter. Specifically, for example, the adjustment of the projection optical system PL can be performed by the adjustment device 68 based on the measurement result.

In the above-described embodiment, it has been described that, when performing correction for acquiring the grating pitch correction information of the scale, wafer table WTB is moved at a low speed (extremely low speed) to the extent that short-term variation of the measurement value of the interferometer can be ignored, but the present invention is not limited to this, and the wafer table WTB may be moved at a speed other than the extremely low speed. In this case, for example, the Y scale 39Y may be acquired₁、39Y₂When the correction information of the grating pitch of (1) is to be obtained, the wafer stage is set at a different position in the X-axis direction, and the wafer stage is moved in the Y-axis direction at the respective positions in the same manner as in the above-described embodiment, while the measurement values of the encoders 70A and 70C and the measurement values of the Y-axis interferometer 16 and the measurement values of the head units 62A and 62C are simultaneously captured during the movement, a continuous cubic equation is created using the sampling values obtained by the two simultaneous capturing operations, and the correction information (for example, correction map) of the grating pitch of the Y scale is independently obtained by solving the continuous cubic equation.

In the above-described embodiment, as shown in fig. 10(a), the optical encoder 70A to 70F is used as a diffractive interference encoder having two mirrors for branching light from a light source by an optical member such as a beam splitter and reflecting the branched light, but the present invention is not limited to this, and a diffractive interference encoder having three gratings, an encoder having a light reflection block disclosed in, for example, japanese patent application laid-open No. 2005-114406, and the like can be used. In the above embodiment, the head units 62A to 62D have a plurality of heads arranged at a predetermined interval, but the present invention is not limited to this, and a single head may be used which includes a light source that emits a light beam to an area that extends in a long and narrow manner in the pitch direction of the Y scale or the X scale, and a plurality of light receiving elements that receive reflected light (diffracted light) from the Y scale or the X scale (diffraction grating) of the light beam and receive the light beam in the pitch direction of the Y scale or the X scale, and are arranged without gaps.

In the above embodiment, the reflection type diffraction grating may be covered with a protective member (for example, a film or a glass plate) that can transmit the detection light from the head units 62A to 62D, so as to prevent damage to the diffraction grating. In the above-described embodiment, the reflection type diffraction grating is provided on the upper surface of wafer stage WST substantially parallel to the XY plane, but the reflection type diffraction grating may be provided on the lower surface of wafer stage WST, for example. At this time, the head units 62A to 62D are disposed on, for example, a base plate facing the lower surface of the wafer stage WST. In the above-described embodiment, wafer stage WST is moved in a horizontal plane, but may be moved in a plane (for example, ZX plane or the like) intersecting the horizontal plane. When reticle stage RST is moved two-dimensionally, an encoder system having the same configuration as the encoder system described above may be provided to measure the positional information of reticle stage RST.

In the above-described embodiment, interferometer system 118 can measure positional information of wafer stage WST in the direction of five degrees of freedom (X-axis, Y-axis, θ X, θ Y, and θ Z), but can also measure positional information in the Z-axis direction. At this time, at least during the exposure operation, the position of wafer stage WST may be controlled using the measurement values of the encoder system and the measurement values of interferometer system 118 (including at least position information in the Z-axis direction). This interferometer system 118 measures positional information in the Z-axis direction of wafer stage WST by providing a reflection surface inclined at a predetermined angle (for example, 45 degrees) with respect to the XY plane on a side surface of wafer stage WST and irradiating a measurement beam with the reflection surface provided on, for example, the barrel holder or the measurement frame via the reflection surface, as disclosed in, for example, japanese patent laid-open No. 2000-323404 (corresponding to U.S. patent No. 7,116,401) and japanese patent laid-open No. 2001-513267 (corresponding to U.S. patent No. 6,208,407). The interferometer system 118 can also measure positional information in the θ x direction and/or the θ y direction other than the Z-axis direction by using a plurality of measurement beams. In this case, a movable mirror for irradiating the wafer stage WST with a measurement beam for measuring positional information in the θ x direction and/or the θ y direction may not be used.

In the above embodiment, the plurality of Z sensors 74 are provided in the head units 62C and 62A_i，j、76_p，qHowever, the present invention is not limited to this, and the same surface position sensor as the Z sensor may be provided in, for example, the measurement frame. Further, the interval between the encoder head and the Z sensor and the upper surface of the wafer stage is preferably equal to or less than the tip lens 191 of the projection optical system PL, for example, is narrow. Thereby, the measurement accuracy can be improved. In this case, since it is difficult to provide an AF sensor, a simple Z sensor is particularly effective.

In the above-described embodiment, the lower surface of the nozzle unit 32 and the lower end surface of the front end optical block of the projection optical system PL are substantially flush with each other, but the present invention is not limited to this, and for example, the lower surface of the nozzle unit 32 may be disposed closer to the image plane (i.e., the wafer) of the projection optical system PL than the emission surface of the front end optical block. That is, the local immersion device 8 is not limited to the above-described structure, and for example, those described in european patent application publication No. 1420298, international publication No. 2004/055803, international publication No. 2004/057590, international publication No. 2005/029559 (corresponding to U.S. patent application publication No. 2006/0231206), international publication No. 2004/086468 (corresponding to U.S. patent application publication No. 2005/0280791), and japanese patent application laid-open No. 2004-289126 (corresponding to U.S. patent application No. 6,952,253), etc. can be used. As disclosed in the pamphlet of international publication No. 2004/019128 (corresponding to U.S. patent application publication No. 2005/0248856), the optical path space on the object surface side of the front end optical unit may be filled with a liquid in addition to the optical path on the image surface side of the front end optical unit. Further, a film having lyophilic and/or dissolution preventing function may be formed on a part (including at least a contact surface with a liquid) or the whole of the surface of the front end optical element. Further, although quartz has high lyophilic properties to liquid and a dissolution preventing film is not required, it is preferable that at least fluorite is formed as a dissolution preventing film.

In the above embodiments, pure water (water) is used as the liquid, but the present invention is not limited to this. It is also possible to use a chemically stable safety liquid having a high transmittance of the illumination light IL as the liquidAnd a body such as a fluorine-based inert liquid. As the fluorine-based inert liquid, for example, floriant (trade name of 3M company, usa) can be used. The fluorine-based inert liquid also has an excellent cooling effect. As the liquid, a liquid having a refractive index higher than that of pure water (refractive index of about 1.44), for example, a refractive index of 1.5 or more, for the illumination light IL may be used. Examples of such a liquid include a predetermined liquid having a C-H bond or an O-H bond such as isopropyl alcohol having a refractive index of about 1.50, glycerin (glycerol) having a refractive index of about 1.61, a predetermined liquid (organic solvent) such as hexane, heptane or decane, Decahydronaphthalene (Decahydronaphthalene) having a refractive index of about 1.60, and the like. Alternatively, any two or more of the above liquids may be mixed, or at least one of the above liquids may be added (mixed) to pure water. Alternatively, H may be added (mixed) to pure water as a liquid⁺、Cs⁺、K⁺、Cl^-、SO₄ ^2-、PO₄ ^2-And the like bases and acids. Further, fine particles of Al oxide or the like may be added (mixed) to pure water. The liquid can transmit ArF excimer laser. Further, it is preferable that the liquid has a small absorption coefficient of light and a small temperature dependency, and is stable against a photosensitive material (or a protective film (top coating film), an antireflection film, or the like) applied to the projection optical system PL and/or the wafer surface. In addition, in the formula F ₂When a laser is used as a light source, perfluoropolyether oil (fomblin oil) is selected. The liquid may have a refractive index higher than that of pure water, for example, about 1.6 to 1.8 for the illumination light IL. Supercritical fluids can also be used as liquids. The front end optical element of the projection optical system PL may be formed of a single crystal material of a fluorinated compound such as quartz (silicon dioxide), calcium fluoride (fluorite), barium fluoride, strontium fluoride, lithium fluoride, or sodium fluoride, or may be formed of a material having a higher refractive index (for example, 1.6 or more) than quartz or fluorite. As the material having a refractive index of 1.6 or more, for example, sapphire, germanium dioxide, or the like disclosed in pamphlet of international publication No. 2005/059617, potassium chloride (having a refractive index of about 1.75) or the like disclosed in pamphlet of international publication No. 2005/059618 can be used.

In the above embodiment, the recovered liquid may be reused, and in this case, a filter (for removing impurities from the recovered liquid) is preferably provided in the liquid recovery device, the recovery pipe, or the like.

In the above-described embodiment, the case where the exposure apparatus is a liquid immersion type exposure apparatus has been described, but the present invention is not limited thereto, and a dry type exposure apparatus that exposes the wafer W without passing a liquid (water) may be used.

In the above-described embodiments, the present invention has been described as being applied to a system including wafer stage WST (movable body), measurement stage MST (another movable body), and alignment system (AL1, AL 2)₁～AL2₄) Exposure apparatuses such as the multipoint AF systems (90A, 90b), the Z sensor, the interferometer system 118, and the encoder systems (70A to 70F) are all used, but the present invention is not limited to this. For example, the present invention can be applied to an exposure apparatus in which the measurement stage MST and the like are not provided. The present invention is applicable to any of the above-described components as long as the wafer stage (moving body) and a part of the other components are included. For example, the invention focusing on the mark detection system can be applied to a device including at least the wafer stage WST and the alignment system. In addition, the interferometer system and the encoder system do not necessarily have to be provided in both.

In the above-described embodiment, although aerial image measuring device 45 has been described as being disposed separately from the different stages, more specifically, as being disposed separately from wafer stage WST and measurement stage MST, the sensors disposed separately are not limited to the aerial image measuring device, and may be, for example, a wavefront aberration measuring instrument. In addition, the different stages are not limited to the combination of the wafer stage and the measurement stage.

In the above-described embodiments, the present invention has been described as being applied to a scanning exposure apparatus such as a step-and-scan system, but the present invention is not limited thereto, and the present invention can also be applied to a stationary exposure apparatus such as a stepper. Even in a stepper or the like, the position of the stage on which the exposure target object is mounted can be measured by the encoder, and the possibility of occurrence of a position measurement error due to air wobble can be made almost zero in the same manner. In this case, the stage can be positioned with high accuracy based on correction information for correcting short-term fluctuations in the measured value of the encoder using the measured value of the interferometer and the measured value of the encoder, and as a result, the reticle pattern with high accuracy can be transferred to the object. The present invention is also applicable to a reduction projection exposure apparatus of a step-and-join method for combining an irradiation field and an irradiation field, an exposure apparatus of a proximity method, a mirror projection alignment exposure apparatus, and the like. The present invention is also applicable to a multi-stage exposure apparatus including a plurality of wafer stages, as disclosed in, for example, Japanese patent application laid-open No. 10-163099, Japanese patent application laid-open No. 10-214783 (corresponding to U.S. Pat. No. 6,590,634), Japanese patent application laid-open No. 2000-505958 (corresponding to U.S. Pat. No. 5,969,441), and U.S. Pat. No. 6,208,407.

The projection optical system in the exposure apparatus according to the above-described embodiment may be not only a reduction system but also any of an equi-magnification system and an enlargement system, and the projection optical system PL may be not only a refraction system but also any of a reflection system and a catadioptric system, and the projection image may be any of an inverted image and an erect image. Further, although the exposure region IA on which the illumination light IL is irradiated via the projection optical system PL includes an on-axis region of the optical axis AX in the field of view of the projection optical system PL, for example, as in the case of the so-called on-line type catadioptric system disclosed in wo 2004/107011, the exposure region may be an off-axis region not including the optical axis AX, and the on-line type catadioptric system may have a plurality of reflection surfaces, and an optical system (reflection system or catadioptric system) forming at least one intermediate image is provided in a part thereof, and has a single optical axis. The illumination area and the exposure area are rectangular in shape, but the shape is not limited to this, and may be, for example, circular arc, trapezoid, or parallelogram.

The light source of the exposure apparatus according to the above embodiment is not limited to the ArF excimer laser light source, and may be any light source Using KrF excimer laser (output wavelength 248nm), F₂Laser (output wavelength 157nm), Ar₂Laser (output wavelength 126nm), Kr₂A pulsed laser source such as a laser (output wavelength 146nm), or an ultra-high pressure mercury lamp that emits bright light such as g-line (wavelength 436nm) or i-line (wavelength 365 nm). Further, a harmonic generator of YAG laser or the like may be used. For example, a harmonic disclosed in pamphlet of international publication No. 1999/46835 (corresponding to U.S. patent No. 7,023,610) can be used, in which a single-wavelength laser beam in the infrared region or the visible region emitted from a DFB semiconductor laser or a fiber laser is amplified as vacuum ultraviolet light by an optical fiber amplifier coated with erbium (or both erbium and ytterbium), and converted into ultraviolet light at a wavelength by nonlinear optical crystallization.

In the above embodiment, the illumination light IL of the exposure apparatus is not limited to light having a wavelength of more than 100nm, and light having a wavelength of less than 100nm may be used. For example, in recent years, in order to expose a pattern of 70nm or less, an EUV exposure apparatus has been developed which generates EUV (extreme Ultra violet) light in a soft X-ray region (for example, a wavelength region of 5 to 15 nm) using an SOR or a plasma laser as a light source, and uses a total reflection reduction optical system and a reflection mask designed at an exposure wavelength (for example, 13.5nm) thereof. The apparatus is constructed to scan and expose the mask and the wafer by using the arc illumination and the synchronous scanning, so that the present invention can be suitably applied to the apparatus. The present invention is also applicable to an exposure apparatus using charged particle beams such as electron beams or ion beams.

In the above-described embodiments, a light transmissive mask (reticle) is used in which a predetermined light shielding pattern (or phase pattern, or dimming pattern) is formed on a light transmissive substrate, but an electronic mask (also referred to as a variable shape mask, an active mask, or an image generator, such as a DMD (Digital Micro-mirror Device) including a non-light emitting type image display element (spatial light modulator)) which forms a transmission pattern, a reflection pattern, or a light emitting pattern based on electronic data of a pattern to be exposed, such as disclosed in, for example, U.S. Pat. No. 6,778,257, may be used instead of this mask.

The present invention is also applicable to an exposure apparatus (lithography system) that forms a pattern of lines with equal intervals on a wafer by forming interference fringes on the wafer, as disclosed in, for example, international publication No. 2001/035168.

Further, for example, the present invention can be applied to an exposure apparatus disclosed in japanese unexamined patent application publication No. 2004-519850 (corresponding to U.S. patent No. 6,611,316), which combines two reticle patterns on a wafer via a projection optical system and performs double exposure on one irradiation region on the wafer substantially simultaneously by one scanning exposure.

The apparatus for forming a pattern on an object is not limited to the exposure apparatus (lithography system), and the present invention can be applied to an apparatus for forming a pattern on an object by an inkjet method, for example.

In the above embodiment, the object to be patterned (the object to be exposed to the energy beam) is not limited to the wafer, and may be another object such as a glass plate, a ceramic substrate, a film member, or a mask substrate.

The use of the exposure apparatus is not limited to exposure apparatuses for semiconductor manufacturing, and can be widely applied to, for example, manufacturing exposure apparatuses for liquid crystal for transferring a liquid crystal display element pattern onto a square glass plate, and manufacturing exposure apparatuses for organic EL, thin film magnetic heads, image pickup devices (such as CCD), micromachines, DNA chips, and the like. In addition to the production of microdevices such as semiconductor devices, the present invention can be applied to an exposure apparatus for transferring a circuit pattern onto a glass substrate, a silicon wafer, or the like in order to produce a reticle or a mask used in a light exposure apparatus, an EUV (extreme ultraviolet) exposure apparatus, an X-ray exposure apparatus, an electron beam exposure apparatus, or the like.

The mark detection device of the present invention is not limited to the exposure device, and can be widely applied to other substrate processing devices (for example, other devices such as a laser repair device and a substrate inspection device), and devices having a moving body such as a stage that moves in a two-dimensional plane, such as a sample positioning device and a wire bonding device in other precision machines.

The exposure apparatus (patterning apparatus) according to the above-described embodiment can be manufactured by assembling various subsystems including the respective components listed in the scope of the present application in order to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. To ensure these various accuracies, adjustments for achieving optical accuracy, mechanical accuracy, and electrical accuracy are performed on various optical systems, mechanical systems, and electrical systems before and after assembly. The process of assembling the various subsystems to the exposure apparatus includes mechanical connection, wiring connection of circuits, piping connection of air pressure circuits, and the like. Of course, before the assembly process from the various subsystems to the exposure apparatus, there is an independent assembly process for each subsystem. When the assembling process from various subsystems to the exposure device is finished, the comprehensive adjustment is carried out to ensure various accuracies of the whole exposure device. Further, it is preferable that the exposure apparatus is manufactured in a clean room in which temperature, cleanliness, and the like are controlled.

Further, the disclosures of all publications, international pamphlets, U.S. patent application publications, and U.S. patent publications relating to exposure apparatuses and the like cited in the above embodiments are incorporated herein by reference.

Next, an embodiment of a device manufacturing method using the exposure apparatus (patterning apparatus) in the photolithography step will be described.

Fig. 37 is a flowchart showing an example of manufacturing a package (a semiconductor chip such as an IC (integrated circuit) or an LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micromachine, or the like). As shown in fig. 37, first, in step 201 (designing step), function/performance design of a component (for example, circuit design of a semiconductor element) is performed, and pattern design for realizing the function is performed. Next, in step 202 (mask making step), a mask on which the designed circuit pattern is formed is made. On the other hand, in step 203 (wafer manufacturing step), a wafer is manufactured using a material such as silicon.

Next, in step 204 (wafer processing step), using the mask and the wafer prepared in steps 201 to 203, actual circuits and the like are formed on the wafer by photolithography and the like as described later. Next, in step 205 (component assembly step), component assembly is performed using the wafer processed in step 204. In step 205, a dicing process, a bonding process, a packaging process (chip encapsulation) and the like are included as necessary.

Finally, in step 206 (inspection step), an inspection such as an operation confirmation test and an endurance test is performed on the component manufactured in step 205. After these steps, the assembly is completed and shipped out of the factory.

Fig. 38 shows a detailed flowchart of step 204 in the semiconductor device. In fig. 38, step 211 (oxidation step) oxidizes the wafer surface. Step 212(CVD (chemical vapor deposition) step) is to form an insulating film on the wafer surface. Step 213 (electrode forming step) forms an electrode on the wafer by evaporation. Step 214 (ion implantation step) implants ions into the wafer. Each of the steps 211 to 214 constitutes a preprocessing step of each stage of the wafer processing, and is selected and executed in accordance with the processing required for each stage.

When the pretreatment step is completed in each stage of the wafer treatment, the post-treatment step is performed as follows. In the post-processing step, first, a photoresist is applied to a wafer in step 215 (photoresist formation step). Next, in step 216 (exposure step), the circuit pattern of the mask is transferred to the wafer using the exposure apparatus (patterning apparatus) and the exposure method (patterning method) described above. Next, in step 217 (developing step), the exposed wafer is developed, and in step 218 (etching step), the exposed member except for the photoresist remaining portion is removed by etching. Next, in step 219 (resist removal step), unnecessary resist after the end of etching is removed.

By repeating these pre-processing steps and post-processing steps, a multi-circuit pattern is formed on the wafer.

By using the device manufacturing method of the present embodiment described above, the exposure apparatus (patterning apparatus) and the exposure method (patterning method) of the above-described embodiments are used in the exposure step (step 216), and therefore, exposure with high throughput can be performed while maintaining high overlay accuracy. Thus, the productivity of a highly integrated module having a fine pattern formed thereon can be improved.

As described above, the pattern forming apparatus, the exposure apparatus, the pattern forming method, the exposure method, and the device manufacturing method according to the present invention are suitable for manufacturing electronic devices such as semiconductor devices and liquid crystal display devices. The mark detection device of the present invention is suitable for detecting a mark on an object mounted on a stage of an exposure device or the like.

Claims

1. An exposure apparatus for exposing an object with an energy beam, comprising:

a movable body capable of holding the object and moving in the 1 st and 2 nd directions in a predetermined plane; and

a mark detection system having a plurality of detection regions at different positions in the 2 nd direction and capable of simultaneously detecting a plurality of marks on the object;

the movable body moves in the 1 st direction, and the mark detection system detects marks on the object at positions different in the 1 st direction, and the number of the marks detected by the mark detection system varies depending on the position of the object in the 1 st direction.

2. The exposure apparatus according to claim 1, characterized in that:

the mark detection system detects a plurality of marks at substantially the same position in the 2 nd direction on the object moving in the 1 st direction using one of the plurality of detection regions.

3. The exposure apparatus according to claim 1, characterized in that:

the mark detection system adjusts the position of the detection area according to the mark arrangement of the object.

4. The exposure apparatus according to claim 3, characterized in that:

The mark detection system adjusts the relative position of the plurality of detection regions in the 2 nd direction in accordance with the position of the mark in the 2 nd direction on the object moved in the 1 st direction.

5. The exposure apparatus according to claim 1, characterized in that:

the mark detection system may change the relative positions of the plurality of detection regions at least in the 2 nd direction.

6. The exposure apparatus according to claim 1, characterized in that:

a plurality of group marks different in position in the 1 st direction on the object are detected by the mark detection system for each group by moving the movable body in the 1 st direction, and at least one of the plurality of group marks includes a plurality of marks different in position in the 2 nd direction.

7. The exposure apparatus according to claim 1, further comprising:

a measuring device having an encoder for measuring positional information of the movable body;

the encoder measures position information of the movable body during an exposure operation of the energy beam to the object and a detection operation of the mark by the mark detection system.

8. The exposure apparatus according to claim 7, characterized in that:

in the movement of the movable body, at least one of the plurality of heads of the encoder for the measurement is switched to another head.

9. The exposure apparatus according to claim 7, characterized in that:

the encoder includes a read head and a grid part in which grids are periodically arranged;

the exposure apparatus further includes:

and a correction device for correcting the measurement error of the encoder caused by the grid part.

10. The exposure apparatus according to claim 9, characterized in that:

the correcting device corrects the measurement error caused by the deformation of the lattice part.

11. The exposure apparatus according to claim 7, characterized in that:

the measuring device includes an interferometer that measures positional information of the movable body;

the exposure apparatus further includes:

and a controller for controlling the movement of the movable body by one or both of the encoder and the interferometer during the exposure operation of the object.

12. The exposure apparatus according to claim 7, characterized in that:

the detection operation of the mark by the mark detection system is performed a plurality of times while changing the focus state of each of the plurality of marks on the object.

13. The exposure apparatus according to claim 7, further comprising:

an optical system for projecting the pattern illuminated by the energy beam onto the object;

an adjusting device for adjusting the optical characteristics of the optical system; and

and a control device for controlling the adjustment device based on a detection result of the mark detection system during the detection operation of the mark by the mark detection system.

14. The exposure apparatus according to claim 7, further comprising:

an optical system for projecting the pattern illuminated by the energy beam onto the object; and

and a controller that performs at least a part of the operations of measuring the projected position of the pattern, detecting the mark by the mark detection system, and the other at the same time.

15. The exposure apparatus according to claim 14, further comprising:

a detection device for detecting positional information of the object in a 3 rd direction orthogonal to the 1 st and 2 nd directions;

the measurement operation of the projection position of the pattern is performed simultaneously with at least a part of the detection operation of the detection device.

16. The exposure apparatus according to claim 7, further comprising:

Another moving body different from the above-described moving body,

the movable body and the other movable body can be set to a 1 st state in which they are close to each other by a predetermined distance or less and a 2 nd state in which they are separated from each other, and the 1 st and 2 nd states can be switched during a detection operation of a mark by the mark detection system.

17. The exposure apparatus according to claim 16, characterized in that:

the detection operation of the marker is started in the 1 st state, and the 1 st state is switched to the 2 nd state during the detection operation of the marker.

18. The exposure apparatus according to claim 7, characterized in that:

the mark detection system comprises a 1 st mark detection system and a 2 nd mark detection system with a position of the detection area changeable;

the measurement of the positional relationship of the detection regions of the 1 st and 2 nd mark detection systems is performed during the exchange operation of the exposed object.

19. The exposure apparatus according to claim 7, further comprising:

a reference member having a pair of reference grids spaced apart in the 2 nd direction and a plurality of reference marks disposed between the pair of reference grids;

The detection of the reference grid by the encoder and the detection of the reference mark by the mark detection system may be performed simultaneously.

20. The exposure apparatus according to claim 7, further comprising:

the mark detection system is configured to perform at least a part of a detection operation of the detection device, and the movable body is moved in the 1 st direction in the detection operation.

21. The exposure apparatus according to claim 20, characterized in that:

the detection point of the detection device is arranged at a position different from the plurality of detection areas in the 1 st direction.

22. The exposure apparatus according to claim 7, further comprising:

an optical system for emitting the energy beam;

another moving body different from the moving body; and

a liquid immersion system for supplying a liquid to a lower vicinity of the optical system to form a liquid immersion area,

by moving the movable body and the other movable body below the optical system, the liquid immersion area is moved from one of the movable body and the other movable body to the other while being maintained at a position close to the lower side of the optical system.

23. A method of manufacturing a component, comprising:

a step of exposing an object using the exposure apparatus according to any one of claims 1 to 22; and

and developing the exposed object.

24. An exposure method for exposing an object with an energy beam, comprising:

a 1 st step of mounting the object on a movable body movable in 1 st and 2 nd directions on a predetermined plane; and

and a 2 nd step of detecting a different number of marks from the position of the object in the 1 st direction by using a mark detection system having a plurality of detection regions different in position in the 2 nd direction when the moving body is moved in the 1 st direction to detect marks different in position in the 1 st direction on the object.

25. The exposure method according to claim 24, characterized in that:

a plurality of marks on the object, the marks being located at substantially the same positions in the 2 nd direction, are detected in one of the plurality of detection regions while the movable body is moved in the 1 st direction.

26. The exposure method according to claim 24, characterized in that:

and adjusting the position of the detection area according to the mark configuration of the object.

27. The exposure method according to claim 26, characterized in that:

adjusting relative positions of the plurality of detection regions in the 2 nd direction based on a position of the mark on the object in the 2 nd direction.

28. The exposure method according to claim 24, characterized in that:

29. The exposure method according to claim 24, characterized in that:

the position information of the movable body is measured by an encoder during an exposure operation of the energy beam to the object and during a detection operation of the mark by the mark detection system.

30. The exposure method according to claim 29, characterized in that:

31. The exposure method according to claim 29, characterized in that:

The measurement error of the encoder caused by the grid part which is irradiated by the measurement beam of the encoder and the grid is periodically arranged is corrected.

32. The exposure method according to claim 31, characterized in that:

correcting the measurement error caused by the deformation of the lattice part.

33. The exposure method according to claim 29, characterized in that:

in the exposure operation of the object, the movement of the movable body is controlled by one or both of the encoder and the interferometer.

34. The exposure method according to claim 29, characterized in that:

35. The exposure method according to claim 29, further comprising:

adjusting an optical characteristic of an optical system that projects a pattern illuminated by the energy beam onto the object, based on a detection result of the mark detection system, during a detection operation of the mark by the mark detection system.

36. The exposure method according to claim 29, characterized in that:

One of a measurement operation of projecting the pattern illuminated by the energy beam onto a pattern projection position of an optical system on the object and a detection operation of the mark by the mark detection system is performed simultaneously with at least a part of the other operation.

37. The exposure method according to claim 36, characterized in that:

the pattern projection position measuring operation is performed simultaneously with at least a part of the detection operation of the position information of the object in the 3 rd direction orthogonal to the 1 st and 2 nd directions.

38. The exposure method according to claim 29, characterized in that:

in the detection operation of the mark by the mark detection system, switching is performed between a 1 st state in which the movable body and another movable body different from the movable body approach each other by a predetermined distance or less and a 2 nd state in which the movable bodies are separated from each other.

39. The exposure method according to claim 38, characterized in that:

40. The exposure method according to claim 29, characterized in that:

The measurement of the positional relationship between the 1 st mark detection system of the mark detection systems and the detection area of the 2 nd mark detection system in which the position of the detection area is changeable is performed during the exchange operation of the exposed object.

41. The exposure method according to claim 29, characterized in that:

the detection of the pair of reference grids spaced apart in the 2 nd direction by the reference member by the encoder and the detection of the plurality of reference marks disposed between the pair of reference grids by the mark detection system may be performed simultaneously.

42. The exposure method according to claim 29, characterized in that:

the detection operation of the mark is performed simultaneously with at least a part of the detection operation of the position information of the object in the 3 rd direction orthogonal to the 1 st and 2 nd directions, and the moving body moves in the 1 st direction in the detection operation.

43. The exposure method according to claim 29, characterized in that:

supplying a liquid to a lower vicinity of an optical system that emits the energy beam to form a liquid immersion area,

the liquid immersion area is moved from one of the movable body and the other movable body to the other while being maintained at a position close to the lower side of the optical system by the movement of the movable body and the other movable body different from the movable body below the optical system.

44. A method of manufacturing a component, comprising:

a step of exposing an object using the exposure method according to any one of claims 24 to 43; and

and developing the exposed object.