CN119200336A

CN119200336A - Exposure method, exposure device, measurement method, and method for manufacturing article

Info

Publication number: CN119200336A
Application number: CN202410804961.1A
Authority: CN
Inventors: 今井烈士
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 2023-06-26
Filing date: 2024-06-21
Publication date: 2024-12-27
Also published as: JP2025004666A; KR20250000445A; TW202503440A

Abstract

The invention provides an exposure method, an exposure apparatus, a measurement method and a manufacturing method of an article, wherein the exposure method is characterized in that the exposure method comprises a first step of obtaining a first measurement value by measuring a position deviation of a stage holding a substrate after the stage is step-driven according to a first driving characteristic, a second step of obtaining a second measurement value by measuring a position deviation of the stage after the stage is step-driven according to a second driving characteristic different from the first driving characteristic, a third step of obtaining a correction value for correcting the position deviation of the stage based on the first measurement value obtained in the first step and the second measurement value obtained in the second step, and a fourth step of obtaining the correction value for correcting the position of the stage by using the correction value obtained in the third step and performing step-driven to expose the substrate held by the stage.

Description

Exposure method, exposure apparatus, measurement method, and method for manufacturing article

Technical Field

The present invention relates to an exposure method, an exposure apparatus, a measurement method, and a method for manufacturing an article.

Background

An exposure apparatus for performing exposure processing on a substrate or a measurement apparatus for performing measurement processing on a substrate has a substrate stage for holding a substrate to be processed. The positional accuracy of the substrate stage is an important factor affecting the accuracy of the exposure process or the measurement process, but may vary depending on the driving conditions for driving the substrate stage. Therefore, regarding the positional accuracy of the substrate stage, techniques for correcting the position of the substrate stage are proposed in Japanese patent application laid-open publication No. 2011-238707, japanese patent application laid-open publication No. 2-82510, and Japanese patent application laid-open publication No. 2003-86284.

Japanese patent application laid-open No. 2011-238707 discloses a technique related to correction of the position of a substrate stage during exposure processing. In this technique, a difference between a position measurement result obtained during acceleration of the substrate stage and a position measurement result obtained during constant speed of the substrate stage is obtained in advance as a correction value of a measurement error caused by the acceleration of the substrate stage. In addition, when the substrate is exposed while the position of the substrate stage (the held substrate) is controlled (positioned) based on the position measurement result obtained during acceleration of the substrate stage, the position of the substrate stage is corrected using the correction value acquired in advance.

Japanese patent application laid-open No. 2-82510 discloses a technique for improving positioning accuracy of a substrate stage. In this technique, in the step driving for positioning each light area of the substrate held by the substrate stage at the exposure position, the substrate stage is driven in a constant direction (one direction) at all times. Accordingly, the inertial force acting on the substrate stage at the time of positioning the substrate stage always becomes a constant direction, and thus, improvement in positioning accuracy of the substrate stage is associated.

Further, japanese patent application laid-open No. 2003-86284 discloses a technique of measuring a positional shift amount of a substrate stage with respect to a target position (target value) at the time of exposing a substrate, and feeding back the positional shift amount to a position measurement result obtained while positioning (aligning) the substrate stage.

Disclosure of Invention

Problems to be solved by the invention

However, when the substrate stage is driven, there is a case where a highly reproducible error occurs between the target position and the actual position of the substrate stage according to driving characteristics (driving conditions) including pitch, speed, acceleration, and the like. In this case, in the conventional technique, sufficient accuracy (that is, the position of the substrate stage cannot be sufficiently corrected) cannot be obtained as the positional accuracy of the substrate stage, and this becomes a factor that reduces the accuracy of the exposure process or the measurement process.

The present invention provides a technique advantageous for reducing positional displacement of a stage.

Means for solving the problems

An exposure method according to an aspect of the present invention is an exposure method for exposing a substrate, the exposure method including a first step of performing a step-by-step drive on a stage holding the substrate according to a first driving characteristic, and then measuring a positional shift of the stage to obtain a first measurement value, a second step of performing a step-by-step drive on the stage according to a second driving characteristic different from the first driving characteristic, and then measuring a positional shift of the stage to obtain a second measurement value, a third step of obtaining a correction value for correcting the positional shift of the stage based on the first measurement value obtained in the first step and the second measurement value obtained in the second step, and a fourth step of performing a step-by-step drive on the stage while correcting the position of the stage with the correction value obtained in the third step, and then exposing the substrate held by the stage.

The exposure apparatus according to another aspect of the present invention is an exposure apparatus for exposing a substrate, the exposure apparatus including a stage for holding the substrate, and a control unit for controlling exposure processing for exposing the substrate held by the stage, wherein the stage is driven stepwise while correcting a position of the stage by a correction value for correcting a position shift of the stage obtained based on a first measurement value obtained by driving the stage stepwise according to a first driving characteristic and a second measurement value obtained by driving the stage stepwise according to a second driving characteristic different from the first driving characteristic, and the substrate held by the stage is exposed.

In a further aspect of the present invention, there is provided a measuring method for measuring an object to be measured, comprising a first step of performing a step-by-step driving of a stage holding the object to be measured according to a first driving characteristic, and then measuring a positional shift of the stage to obtain a first measured value, a second step of performing a step-by-step driving of the stage according to a second driving characteristic different from the first driving characteristic, and then measuring a positional shift of the stage to obtain a second measured value, and a third step of obtaining a correction value for correcting the positional shift of the stage based on the first measured value obtained in the first step and the second measured value obtained in the second step, and a fourth step of performing a step-by-step driving of the stage while correcting the position of the stage with the correction value obtained in the third step, and then measuring the object to be measured held by the stage.

The method for producing an article according to still another aspect of the present invention is a method for producing an article, comprising the steps of exposing a substrate by the exposure method, developing the exposed substrate, and producing an article from the developed substrate.

Another object or other means of the present invention will be elucidated in the embodiments described hereinafter with reference to the drawings.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, for example, a technique advantageous for reducing positional displacement of a stage can be provided.

Drawings

Fig. 1 is a schematic diagram showing a configuration of an exposure apparatus according to an embodiment of the present invention.

Fig. 2 is a perspective view showing a structure of the periphery of the substrate stage.

Fig. 3 is a schematic diagram showing a structure of an alignment optical system.

Fig. 4A and 4B are diagrams for explaining a positional shift of the substrate stage caused by the step drive of the substrate stage.

Fig. 5 is a flowchart for explaining a method of reducing positional deviation caused by a stepping drive speed of a substrate stage.

Fig. 6 is a flowchart for explaining a method of reducing positional deviation caused by stepping drive acceleration of the substrate stage.

Fig. 7 is a flowchart for explaining a method of reducing positional deviation caused by the stepping direction of the substrate stage.

Fig. 8 is a flowchart for explaining a method of reducing positional deviation caused by a stepping drive speed of a substrate stage.

Fig. 9 is a flowchart for explaining a method of reducing positional deviation caused by stepping drive acceleration of the substrate stage.

Fig. 10 is a flowchart for explaining a method of reducing positional deviation caused by the stepping direction of the substrate stage.

Detailed Description

The embodiments are described in detail below with reference to the drawings. The following embodiments do not limit the invention according to the claims. Although the plurality of features are described in the embodiments, not all of the plurality of features are necessary for the invention, and the plurality of features may be arbitrarily combined. In the drawings, the same or similar structures are denoted by the same reference numerals, and repetitive description thereof will be omitted.

Fig. 1 is a schematic diagram showing a configuration of an exposure apparatus 1 according to an embodiment of the present invention. The exposure apparatus 1 is a lithographic apparatus used in a process of manufacturing a device such as a semiconductor device, and is configured to expose a substrate using a master (mask or reticle) to form a pattern on the substrate. In the present embodiment, the exposure apparatus 1 performs a process (exposure process) of projecting a pattern formed on an original plate onto a substrate via a projection optical system and transferring the original plate pattern onto the substrate.

The exposure apparatus 1 is implemented, for example, as an exposure apparatus (stepper) that fixes the master (i.e., in a step-and-repeat manner) and transfers the pattern of the master onto the substrate. The exposure apparatus 1 may be realized as a scanning type exposure apparatus (scanner) that transfers the original pattern onto the substrate while scanning the original and the substrate in synchronization with each other in the scanning direction (i.e., in a step-and-scan system).

In the present specification and the drawings, directions are represented by XYZ coordinate systems in which directions parallel to a surface on which the substrate is disposed are defined as XY planes. Directions parallel to the X-axis, the Y-axis, and the Z-axis in the XYZ coordinate system are set as the X-direction, the Y-direction, and the Z-direction, and the rotation about the X-axis, the rotation about the Y-axis, and the rotation about the Z-axis are set as θx, θy, and θz, respectively.

As shown in fig. 1, the exposure apparatus 1 has a projection optical system PO that projects a pattern formed on a master OR onto a substrate, a substrate stage 101 that holds a substrate 102, and an alignment optical system 103 that detects an alignment mark provided on the substrate 102. The exposure apparatus 1 further includes a driving unit 104 that drives the substrate stage 101, a measuring unit 106 that measures the position of the substrate stage 101, a control unit 107, and a storage unit SU.

The control unit 107 is configured by a computer (information processing device) including a CPU, a memory, and the like, for example, and controls the respective units of the exposure apparatus 1 in a unified manner according to a program stored in the storage unit SU or the like. In the present embodiment, the control unit 107 controls exposure processing for exposing the substrate 102 via the master OR.

The storage unit SU stores programs and various information (data) and the like necessary for controlling the respective portions of the exposure apparatus 1 to perform exposure processing.

Fig. 2 is a perspective view showing the structure of the periphery of the substrate stage 101. The substrate stage 101 is configured as an xyθ stage that can be driven in the X direction, the Y direction, and the rotation (θ) direction about the Z axis, for example.

The driving unit 104 has a function of driving the substrate stage 101. In the present embodiment, the driving section 104 includes a motor 104X for driving the substrate stage 101 in the X direction, a motor 104Y for driving the substrate stage 101 in the Y direction, and a motor (not shown) for rotationally driving the substrate stage 101 in the θ direction.

The measurement unit 106 has a function of measuring the position of the substrate stage 101, and includes laser interferometers 106X, 106Y, and 106 θ in this embodiment. The laser interferometers 106X, 106Y, and 106 θ measure the positions of the substrate stage 101 in the X direction, the Y direction, and the θ direction by irradiating the mirrors 105X and 105Y fixed to the substrate stage 101 with light and detecting the light reflected by the mirrors 105X and 105Y.

The control unit 107 constantly measures (monitors) the position of the substrate stage 101 via the measurement unit 106, and drives the substrate stage 101 to a target position via the driving unit 104 based on the measurement result, thereby positioning the substrate stage. The control unit 107 maintains the substrate stage 101 at the target position based on the measurement result of the measurement unit 106 even after the substrate stage 101 is positioned.

Fig. 3 is a schematic diagram showing the structure of the alignment optical system 103. The alignment optical system 103 is configured as an off-axis viewer (off-axis scope), and has a function of optically detecting an alignment mark assigned to (each of the light areas of) the substrate 102 and acquiring position measurement data. The position measurement data is also a measurement value related to the position of the substrate 102 held by the substrate stage 101.

In the present embodiment, the alignment optical system 103 includes a light source 201, a beam splitter 202, lenses 203 and 206, and a sensor 207. Light from the light source 201 is reflected by the beam splitter 202, and an alignment mark 204 (pre-alignment mark) or 205 (fine alignment mark) provided on the substrate 102 is illuminated via the lens 203. The light diffracted by the alignment mark 204 or 205 is received by the sensor 207 via the lens 203, the beam splitter 202, and the lens 206.

In the exposure apparatus 1, when performing exposure processing for each of the plurality of light areas of the substrate 102, the substrate stage 101 needs to be driven according to the driving characteristics, but there is a case where positional displacement occurs on the substrate stage 101 according to the driving characteristics. Such positional displacement of the substrate stage 101 becomes remarkable in driving of the substrate stage 101 for positioning each illumination region of the substrate 102 at an exposure position, so-called step driving. Here, the driving characteristics are characteristics that prescribe at least one of a speed, an acceleration, and a driving direction (step direction) in driving (including step driving) of the substrate stage 101. The positional displacement of the substrate stage 101 is an error with high reproducibility that occurs between the target position and the actual position of the substrate stage 101. The step drive is also a drive (drive between light irradiation regions) of the substrate stage 101 required to expose a certain light irradiation region of the substrate 102 and then position the next light irradiation region in the exposure position.

The positional displacement of the substrate stage 101 caused by the step driving of the substrate stage 101 will be specifically described with reference to fig. 4A and 4B. Fig. 4A shows a state (lighting layout) in which a plurality of lighting areas 301 are arranged in desired positions over the substrate 102. The step direction 302 indicates a direction in which the substrate stage 101 is driven in step driving of the substrate stage 101. Fig. 4B shows positions of exposure regions 303 (exposure results) formed on the substrate 102 by performing exposure processing on the plurality of light irradiation regions 301 on the substrate 102 while driving the substrate stage 101 in steps. As shown in fig. 4B, a positional shift with high reproducibility occurs between the illumination region 301 and the exposure region 303 due to the step driving of the substrate stage 101, specifically, according to the speed, acceleration, or step direction of the step driving of the substrate stage 101. The positional shift between the light irradiation region 301 and the exposure region 303 on the substrate 102 corresponds to the positional shift of the substrate stage 101. If the substrate stage 101 is driven stepwise at a low speed or a low acceleration, the positional shift of the substrate stage 101 (the positional shift of the light irradiation region 301 and the exposure region 303) can be reduced. However, since the time required for the step driving of the substrate stage 101 becomes long, there is a possibility that the throughput is reduced.

Therefore, in the present embodiment, a new technique is provided that reduces the positional displacement of the substrate stage 101 caused by the step driving of the substrate stage 101 without step-driving the substrate stage 101 at a low speed or at a low acceleration.

First, a method (exposure method) of reducing the positional deviation of the substrate stage 101 generated according to the speed of the step drive (step drive speed) of the substrate stage 101 will be described with reference to fig. 5. As described above, the control unit 107 controls the respective units of the exposure apparatus 1 in a unified manner to perform the method.

In S401, referring to exposure recipe data (recipe) for exposing the substrate 102, it is determined whether or not the maximum speed of the step drive of the substrate stage 101, that is, the maximum speed of the step drive speed is the initial speed with respect to the light irradiation layout of the substrate 102. If the maximum speed of the step driving speed is not the initial speed, the process proceeds to S406. On the other hand, if the maximum speed of the step driving speed is the initial speed, the process proceeds to S402.

In S402, the substrate stage 101 is driven stepwise at a low speed (first driving characteristic), and then, the positional displacement of the substrate stage 101 is measured while the substrate stage 101 is stationary, and a first measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the first speed, alignment marks provided in the respective light irradiation regions of the substrate 102 held by the substrate stage 101 are detected by the alignment optical system 103, whereby the positional displacement of the substrate stage 101 is measured. In this way, S402 is a step (first step) of obtaining a first measurement value by measuring the positional shift of the substrate stage 101 after the substrate stage 101 holding the substrate 102 is step-driven according to the first driving characteristic.

In S403, the substrate stage 101 is driven stepwise at a high speed (a second driving characteristic different from the first driving characteristic), and then the positional displacement of the substrate stage 101 is measured while the substrate stage 101 is stationary, and a second measurement value is obtained. Specifically, after the substrate stage 101 is step-driven at the second speed, an alignment mark provided on the substrate 102 held by the substrate stage 101 is detected by the alignment optical system 103, whereby the positional displacement of the substrate stage 101 is measured. In this way, S403 is a step (second step) of performing step driving on the substrate stage 101 holding the substrate 102 according to the second driving characteristic, and then measuring the positional shift of the substrate stage 101 to obtain a second measurement value.

The maximum speed (second speed) of the step driving speed in S403 may be larger than the maximum speed (first speed) of the step driving speed in S402. The maximum speed of the step driving speed in S403 is preferably the maximum speed (same speed as the maximum speed) of the step driving speed when the exposure process is actually performed on each light area of the substrate 102. In other words, in S403, the driving characteristic (second driving characteristic) when the substrate stage 101 is step-driven may be an actual exposure driving characteristic (same as) that prescribes step-driving of the substrate stage 101 when the substrate 102 is exposed.

In S404, a correction value for correcting the positional shift of the substrate stage 101 generated by the step driving speed is obtained based on the first measurement value obtained in S402 and the second measurement value obtained in S403 (third step). For example, in the case where the second drive characteristic is an actual exposure drive characteristic, a difference between the first measurement value and the second measurement value is taken as a correction value for correcting the positional deviation of the substrate stage 101. In addition, when the second driving characteristic is not the actual exposure driving characteristic, for example, linear interpolation or the like is performed on the difference between the first measurement value and the second measurement value, and a correction value for correcting the positional shift of the substrate stage 101 is obtained.

In S405, the correction amount obtained in S404 is stored in the storage unit SU included in the exposure apparatus 1 in association with the exposure recipe data (the exposure recipe data referred to in S401, in particular, the maximum speed of the stepping drive speed included in the exposure recipe data) (fifth step).

In S406, the substrate stage 101 is driven stepwise while the position of the substrate stage 101 is corrected by the correction amount obtained in S404, that is, the correction amount stored in the storage unit SU, and the substrate 102 held by the substrate stage 101 is exposed (fourth step). For example, the position (positional deviation) of the substrate stage 101 is corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the measurement value of the position of the substrate stage 101 measured by the measuring section 106 during the step-driving of the substrate stage 101. The position of the substrate stage 101 may be corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the target position of the substrate stage 101 during the step-driving of the substrate stage 101.

As described above, according to the present embodiment, the positional displacement of the substrate stage 101 caused by the stepping drive speed can be reduced, and the reduction in accuracy of the exposure process can be suppressed.

Next, a method (exposure method) of reducing the positional deviation of the substrate stage 101 generated by the acceleration of the step drive (step drive acceleration) of the substrate stage 101 will be described with reference to fig. 6. As described above, the control unit 107 controls the respective units of the exposure apparatus 1 in a unified manner to perform the method.

In S501, referring to the exposure recipe data for exposing the substrate 102, it is determined whether or not the maximum acceleration of the step drive of the substrate stage 101, that is, the maximum acceleration of the step drive acceleration, is the initial acceleration with respect to the illumination layout of the substrate 102. If the maximum acceleration of the step driving acceleration is not the initial acceleration, the process proceeds to S506. On the other hand, when the maximum acceleration of the step driving acceleration is the initial acceleration, the process proceeds to S502.

In S502, the substrate stage 101 is driven stepwise with a low acceleration (first driving characteristic), and then, the positional displacement of the substrate stage 101 is measured while the substrate stage 101 is stationary, and a first measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the first acceleration, the alignment marks provided in the respective light irradiation regions of the substrate 102 held by the substrate stage 101 are detected by the alignment optical system 103, and the positional displacement of the substrate stage 101 is measured. In this way, S502 is a step (first step) of obtaining a first measurement value by measuring the positional shift of the substrate stage 101 after the substrate stage 101 holding the substrate 102 is step-driven according to the first driving characteristic.

In S503, the substrate stage 101 is step-driven with a high acceleration (a second driving characteristic different from the first driving characteristic), and then, the positional displacement of the substrate stage 101 is measured while the substrate stage 101 is stationary, and a second measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the second acceleration, an alignment mark provided on the substrate 102 held by the substrate stage 101 is detected by the alignment optical system 103, whereby the positional displacement of the substrate stage 101 is measured. In this way, S503 is a step (second step) of performing step driving of the substrate stage 101 holding the substrate 102 in accordance with the second driving characteristic, and then measuring the positional shift of the substrate stage 101 to obtain a second measurement value.

The maximum acceleration (second acceleration) of the step driving acceleration in S503 may be larger than the maximum acceleration (first acceleration) of the step driving acceleration in S502. The maximum acceleration of the step driving acceleration in S503 is preferably the maximum acceleration of the step driving acceleration (the same acceleration as the maximum acceleration) when the exposure process is actually performed on each illumination area of the substrate 102. In other words, in S503, the driving characteristic (second driving characteristic) when the substrate stage 101 is step-driven may be an actual exposure driving characteristic (same as) that prescribes step-driving of the substrate stage 101 when the substrate 102 is exposed.

In S504, a correction value for correcting the positional deviation of the substrate stage 101 generated by the step driving acceleration is obtained based on the first measurement value obtained in S502 and the second measurement value obtained in S503 (third step). For example, in the case where the second drive characteristic is an actual exposure drive characteristic, a difference between the first measurement value and the second measurement value is taken as a correction value for correcting the positional deviation of the substrate stage 101. In addition, when the second driving characteristic is not the actual exposure driving characteristic, for example, linear interpolation or the like is performed on the difference between the first measurement value and the second measurement value, and a correction value for correcting the positional shift of the substrate stage 101 is obtained.

In S505, the correction amount obtained in S504 is stored in the storage unit SU included in the exposure apparatus 1 in association with the exposure recipe data (the exposure recipe data referred to in S501, in particular, the maximum acceleration of the stepping drive acceleration included in the exposure recipe data) (fifth step).

In S506, the substrate stage 101 is driven stepwise while the position of the substrate stage 101 is corrected by the correction amount obtained in S504, that is, the correction amount stored in the storage unit SU, and the substrate 102 held by the substrate stage 101 is exposed (fourth step). For example, the position (positional deviation) of the substrate stage 101 is corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the measurement value of the position of the substrate stage 101 measured by the measuring section 106 during the step-driving of the substrate stage 101. The position of the substrate stage 101 may be corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the target position of the substrate stage 101 during the step-driving of the substrate stage 101.

As described above, according to the present embodiment, the positional displacement of the substrate stage 101 caused by the stepping drive acceleration can be reduced, and the reduction in accuracy of the exposure process can be suppressed.

Next, a method (exposure method) of reducing the positional deviation of the substrate stage 101 generated in accordance with the step direction of the step driving of the substrate stage 101 will be described with reference to fig. 7. As described above, the control unit 107 controls the respective units of the exposure apparatus 1 in a unified manner to perform the method.

In S601, referring to exposure recipe data for exposing the substrate 102, it is determined whether or not the stepping direction of the stepping drive of the substrate stage 101 is the first direction with respect to the light irradiation layout of the substrate 102. If the step direction is not the initial direction, the process proceeds to S606. On the other hand, if the step direction is the first direction, the process proceeds to S602.

In S602, the substrate stage 101 is driven in a step in a first direction (with a first driving characteristic), and then, the positional displacement of the substrate stage 101 is measured while the substrate stage 101 is stationary, and a first measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise in the first direction, alignment marks provided in the respective light irradiation regions of the substrate 102 held by the substrate stage 101 are detected by the alignment optical system 103, whereby the positional displacement of the substrate stage 101 is measured. In this way, S602 is a step (first step) of obtaining a first measurement value by measuring the positional shift of the substrate stage 101 after the substrate stage 101 holding the substrate 102 is step-driven according to the first driving characteristic. The first direction is, for example, a different (i.e., opposite) step direction from the step direction when the exposure process is actually performed on each of the light areas of the substrate 102.

In S603, the substrate stage 101 is driven in a step in the second direction (with the second driving characteristic), and then, the positional displacement of the substrate stage 101 is measured while the substrate stage 101 is stationary, and a second measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise in the second direction, the alignment optical system 103 detects alignment marks provided in the respective light irradiation regions of the substrate 102 held by the substrate stage 101, and thereby the positional displacement of the substrate stage 101 is measured. In this way, S603 is a step (second step) of performing step driving of the substrate stage 101 holding the substrate 102 according to the second driving characteristic, and then measuring the positional shift of the substrate stage 101 to obtain a second measurement value. The second direction is, for example, a stepping direction (same direction as the first direction) when the exposure process is actually performed on each of the light areas of the substrate 102. In other words, in S603, the driving characteristic (second driving characteristic) when the substrate stage 101 is step-driven is an actual exposure driving characteristic (same as) that prescribes step-driving of the substrate stage 101 when the substrate 102 is exposed.

In S604, a correction value for correcting the positional shift of the substrate stage 101 generated in accordance with the stepping direction is obtained based on the first measurement value obtained in S602 and the second measurement value obtained in S603 (third step). For example, half of the difference between the first measurement value and the second measurement value is used as a correction value for correcting the positional deviation of the substrate stage 101.

In S605, the correction amount obtained in S604 is stored in the storage unit SU included in the exposure apparatus 1 in association with the exposure recipe data (the exposure recipe data referred to in S601, in particular, the step direction included in the exposure recipe data) (fifth step).

In S606, the substrate stage 101 is driven stepwise while the position of the substrate stage 101 is corrected by the correction amount obtained in S604, that is, the correction amount stored in the storage unit SU, and the substrate 102 held by the substrate stage 101 is exposed (fourth step). For example, the position (positional deviation) of the substrate stage 101 is corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the measurement value of the position of the substrate stage 101 measured by the measuring section 106 during the step-driving of the substrate stage 101. The position of the substrate stage 101 may be corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the target position of the substrate stage 101 during the step-driving of the substrate stage 101.

As described above, according to the present embodiment, the positional displacement of the substrate stage 101 caused by the stepping direction can be reduced, and the reduction in accuracy of the exposure process can be suppressed.

Instead of detecting the alignment mark provided on the substrate 102, the positional displacement of the substrate stage 101 due to the step driving of the substrate stage 101 can be reduced based on the result (exposure result) obtained by exposing the substrate 102. Next, a method of reducing positional displacement of the substrate stage 101 using the exposure result will be described.

First, a method (exposure method) of reducing the positional deviation of the substrate stage 101 generated according to the speed of the step drive (step drive speed) of the substrate stage 101 will be described with reference to fig. 8.

In S701, referring to the exposure recipe data for exposing the substrate 102, it is determined whether or not the maximum speed of the step drive of the substrate stage 101, that is, the maximum speed of the step drive speed is the first speed with respect to the illumination layout of the substrate 102. If the maximum speed of the step driving speed is not the initial speed, the process proceeds to S706. On the other hand, in the case where the maximum speed of the step driving speed is the initial speed, the process proceeds to S702.

In S702, the substrate stage 101 is driven at a low speed (first driving characteristic), and then, the positional displacement of the substrate stage 101 is measured based on the exposure result of exposing the substrate 102, and a first measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the first speed, the overlay mark obtained by exposing the substrate 102 is inspected by the overlay inspection device, whereby the positional displacement of the substrate stage 101 is measured. In this way, S702 is a step (first step) of obtaining a first measurement value by measuring the positional shift of the substrate stage 101 after the substrate stage 101 holding the substrate 102 is step-driven according to the first driving characteristic.

In S703, the substrate stage 101 is driven stepwise at a high speed (second driving characteristic), and then, based on the exposure result of exposing the substrate 102, the positional displacement of the substrate stage 101 is measured, and a second measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the second speed, the overlay mark obtained by exposing the substrate 102 is inspected by the overlay inspection device, whereby the positional displacement of the substrate stage 101 is measured. In this way, S703 is a step (second step) of performing step driving on the substrate stage 101 holding the substrate 102 according to the second driving characteristic, and then measuring the positional shift of the substrate stage 101 to obtain a second measurement value.

The maximum speed (second speed) of the step driving speed in S703 may be larger than the maximum speed (first speed) of the step driving speed in S702. However, the maximum speed of the step driving speed in S703 is preferably the maximum speed (same speed as the maximum speed) of the step driving speed when the exposure process is actually performed on each light area of the substrate 102. In other words, in S703, the driving characteristic (second driving characteristic) when the substrate stage 101 is step-driven may be an actual exposure driving characteristic (same as) that prescribes step-driving of the substrate stage 101 when the substrate 102 is exposed.

In S704, a correction value for correcting the positional shift of the substrate stage 101 generated by the step driving speed is obtained based on the first measurement value obtained in S702 and the second measurement value obtained in S703 (third step). For example, in the case where the second drive characteristic is an actual exposure drive characteristic, a difference between the first measurement value and the second measurement value is taken as a correction value for correcting the positional deviation of the substrate stage 101. In addition, when the second driving characteristic is not the actual exposure driving characteristic, for example, linear interpolation or the like is performed on the difference between the first measurement value and the second measurement value, and a correction value for correcting the positional shift of the substrate stage 101 is obtained.

In S705, the correction amount obtained in S704 is stored in the storage unit SU included in the exposure apparatus 1 in association with the exposure recipe data (the exposure recipe data referred to in S701, in particular, the maximum speed of the stepping drive speed included in the exposure recipe data) (fifth step).

In S706, the substrate stage 101 is driven in steps while the position of the substrate stage 101 is corrected by the correction amount obtained in S704, that is, the correction amount stored in the storage unit SU, and the substrate 102 held by the substrate stage 101 is exposed (fourth step). For example, the position (positional deviation) of the substrate stage 101 is corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the measurement value of the position of the substrate stage 101 measured by the measuring section 106 during the step-driving of the substrate stage 101. The position of the substrate stage 101 may be corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the target position of the substrate stage 101 during the step-driving of the substrate stage 101.

Next, a method (exposure method) of reducing the positional deviation of the substrate stage 101 generated by the acceleration of the step drive (step drive acceleration) of the substrate stage 101 will be described with reference to fig. 9.

In S801, referring to exposure recipe data for exposing the substrate 102, it is determined whether or not the maximum acceleration of the step drive of the substrate stage 101, that is, the maximum acceleration of the step drive acceleration, is the initial acceleration with respect to the illumination layout of the substrate 102. If the maximum acceleration of the step driving acceleration is not the initial acceleration, the routine proceeds to S806. On the other hand, when the maximum acceleration of the step driving acceleration is the first acceleration, the process proceeds to S802.

In S802, the substrate stage 101 is driven stepwise with a low acceleration (first driving characteristic), and then, based on the exposure result of exposing the substrate 102, the positional displacement of the substrate stage 101 is measured, and a first measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the first acceleration, the overlay mark obtained by exposing the substrate 102 is inspected by the overlay inspection device, whereby the positional displacement of the substrate stage 101 is measured. In this way, S802 is a step (first step) of obtaining a first measurement value by measuring the positional shift of the substrate stage 101 after the substrate stage 101 holding the substrate 102 is step-driven according to the first driving characteristic.

In S803, the substrate stage 101 is driven stepwise with a high acceleration (second driving characteristic), and then, based on the exposure result of exposing the substrate 102, the positional displacement of the substrate stage 101 is measured, and a second measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise at the second acceleration, the overlay mark obtained by exposing the substrate 102 is inspected by the overlay inspection device, whereby the positional displacement of the substrate stage 101 is measured. In this way, S803 is a step (second step) of performing step driving of the substrate stage 101 holding the substrate 102 in accordance with the second driving characteristic, and then measuring the positional shift of the substrate stage 101 to obtain a second measurement value.

The maximum acceleration (second acceleration) of the step driving acceleration in S803 may be larger than the maximum acceleration (first acceleration) of the step driving acceleration in S702. The maximum acceleration of the step driving acceleration in S803 is preferably the maximum acceleration of the step driving acceleration (the same acceleration as the maximum acceleration) when the exposure process is actually performed on each illumination region of the substrate 102. In other words, in S803, the driving characteristic (second driving characteristic) when the substrate stage 101 is step-driven may be an actual exposure driving characteristic (same as) that prescribes step-driving of the substrate stage 101 when the substrate 102 is exposed.

In S804, a correction value for correcting the positional deviation of the substrate stage 101 generated by the step driving acceleration is obtained based on the first measurement value obtained in S802 and the second measurement value obtained in S803 (third step). For example, in the case where the second drive characteristic is an actual exposure drive characteristic, a difference between the first measurement value and the second measurement value is taken as a correction value for correcting the positional deviation of the substrate stage 101. In addition, when the second driving characteristic is not the actual exposure driving characteristic, for example, linear interpolation or the like is performed on the difference between the first measurement value and the second measurement value, and a correction value for correcting the positional shift of the substrate stage 101 is obtained.

In S805, the correction amount obtained in S804 is stored in the storage unit SU included in the exposure apparatus 1 in association with the exposure recipe data (the exposure recipe data referred to in S801, in particular, the maximum acceleration of the stepping drive acceleration included in the exposure recipe data) (fifth step).

In S806, the substrate stage 101 is driven stepwise while the position of the substrate stage 101 is corrected by the correction amount obtained in S804, that is, the correction amount stored in the storage unit SU, and the substrate 102 held by the substrate stage 101 is exposed (fourth step). For example, the position (positional deviation) of the substrate stage 101 is corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the measurement value of the position of the substrate stage 101 measured by the measuring section 106 during the step-driving of the substrate stage 101. The position of the substrate stage 101 may be corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the target position of the substrate stage 101 during the step-driving of the substrate stage 101.

Next, a method (exposure method) of reducing the positional deviation of the substrate stage 101 generated in accordance with the step direction of the step driving of the substrate stage 101 will be described with reference to fig. 10.

In S901, referring to exposure recipe data for exposing the substrate 102, it is determined whether or not the stepping direction of the stepping drive of the substrate stage 101 is the first direction with respect to the light layout of the substrate 102. If the step direction is not the initial direction, the process proceeds to S906. On the other hand, if the step direction is the first direction, the process proceeds to S902.

In S902, the substrate stage 101 is driven in a step in a first direction (with a first driving characteristic), and then, based on an exposure result of exposing the substrate 102, the positional displacement of the substrate stage 101 is measured, and a first measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise in the first direction, the overlay mark obtained by exposing the substrate 102 is inspected by the overlay inspection device, whereby the positional displacement of the substrate stage 101 is measured. In this way, S902 is a step (first step) of obtaining a first measurement value by measuring the positional shift of the substrate stage 101 after the substrate stage 101 holding the substrate 102 is step-driven according to the first driving characteristic. The first direction is, for example, a different (i.e., opposite) step direction from the step direction when the exposure process is actually performed on each of the light areas of the substrate 102.

In S903, the substrate stage 101 is driven in a step in the second direction (with the second driving characteristic), and then, based on the exposure result of exposing the substrate 102, the positional displacement of the substrate stage 101 is measured, and a second measurement value is obtained. Specifically, after the substrate stage 101 is driven stepwise in the second direction, the overlay mark obtained by exposing the substrate 102 is inspected by the overlay inspection device, whereby the positional displacement of the substrate stage 101 is measured. In this way, S903 is a step (second step) of performing step driving of the substrate stage 101 holding the substrate 102 in accordance with the second driving characteristic, and then measuring the positional shift of the substrate stage 101 to obtain a second measurement value. The second direction is, for example, a stepping direction (same direction as the first direction) when the exposure process is actually performed on each of the light areas of the substrate 102. In other words, in S903, the driving characteristic (second driving characteristic) when the substrate stage 101 is step-driven is an actual exposure driving characteristic (same as) that prescribes step-driving of the substrate stage 101 when the substrate 102 is exposed.

In S904, a correction value for correcting the positional shift of the substrate stage 101 generated in accordance with the stepping direction is obtained based on the first measurement value obtained in S902 and the second measurement value obtained in S903 (third step). For example, half of the difference between the first measurement value and the second measurement value is taken as a correction value for correcting the positional deviation of the substrate stage 101.

In S905, the correction amount obtained in S904 is stored in the storage unit SU included in the exposure apparatus 1 in association with the exposure recipe data (the exposure recipe data referred to in S901, in particular, the step direction included in the exposure recipe data) (fifth step).

In S906, the substrate stage 101 is driven in steps while the position of the substrate stage 101 is corrected by the correction amount obtained in S904, that is, the correction amount stored in the storage unit SU, and the substrate 102 held by the substrate stage 101 is exposed (fourth step). For example, the position (positional deviation) of the substrate stage 101 is corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the measurement value of the position of the substrate stage 101 measured by the measuring section 106 during the step-driving of the substrate stage 101. The position of the substrate stage 101 may be corrected by performing the step-driving of the substrate stage 101 while reflecting the correction value to the target position of the substrate stage 101 during the step-driving of the substrate stage 101.

In the present embodiment, when the exposure recipe data (including the step driving speed, the step driving acceleration, and the step direction) is the first exposure recipe data, the correction value is stored in association with the exposure recipe data. However, even when the exposure recipe data is not the first exposure recipe data, there is a possibility that the correction value may vary due to a change with time or the like. Therefore, the correction value stored in association with the exposure recipe data is preferably updated periodically.

In the present embodiment, when the substrate 102 is exposed, the positional displacement of the substrate stage 101 due to the step drive of the substrate stage 101 is reduced (corrected). Therefore, alignment (fine adjustment) of the substrate 102 (the substrate stage 101 holding the substrate 102) after the step driving is basically not required. But the alignment of the substrate 102 may be performed after the substrate stage 101 is driven stepwise. In this case, since the positional displacement of the substrate stage 101 due to the step driving of the substrate stage 101 is reduced, it is advantageous from the viewpoint of time required for alignment of the substrate 102.

In addition, although the present embodiment has been described by taking an exposure method as an example, the present invention can also be applied to a measurement method in which a stage holding a measurement object is driven stepwise and then the measurement object held on the stage is measured. In this case, the stage may be driven stepwise to measure the object held by the stage while correcting the position of the stage holding the object with the correction values obtained through the first, second, and third steps.

The method for manufacturing an article according to the embodiment of the present invention is suitable for manufacturing an article such as a liquid crystal display element, a semiconductor element, a flat panel display, or MEMS. The manufacturing method includes a step of exposing the substrate coated with the photosensitive agent using the exposure apparatus 1 or the exposure method described above, and a step of developing the photosensitive agent after exposure. Further, the circuit pattern is formed on the substrate by performing an etching process, an ion implantation process, or the like on the substrate using the developed pattern of the photosensitive agent as a mask. These steps of exposure, development, etching, and the like are repeated to form a circuit pattern composed of a plurality of layers on a substrate. In the subsequent step, the circuit pattern-formed substrate is subjected to die cutting (processing), and the chip mounting, bonding, and inspection steps are performed. The production method may further include other known steps (oxidation, film formation, vapor deposition, doping, planarization, resist stripping, and the like). The method for manufacturing an article according to the present embodiment is advantageous in at least one of performance, quality, productivity, and production cost of the article as compared with the conventional method.

The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the claims are appended to disclose the scope of the invention.

Claims

1. An exposure method for exposing a substrate, characterized in that,

The exposure method comprises the following steps:

a first step of performing step-driving of a stage holding the substrate according to a first driving characteristic, and then measuring a positional shift of the stage to obtain a first measurement value;

a second step of performing step-driving of the stage according to a second driving characteristic different from the first driving characteristic, and then measuring a positional shift of the stage to obtain a second measurement value;

A third step of obtaining a correction value for correcting the positional shift of the stage based on the first measurement value obtained in the first step and the second measurement value obtained in the second step, and

And a fourth step of performing step-by-step driving of the stage to expose the substrate held by the stage while correcting the position of the stage with the correction value obtained in the third step.

2. The exposure method according to claim 1, wherein,

The second driving characteristic is a driving characteristic that prescribes a step driving of the stage when exposing the substrate.

3. The exposure method according to claim 1, wherein,

The first driving characteristic and the second driving characteristic are driving characteristics that specify at least one of a speed, an acceleration, and a driving direction of step driving of the stage.

4. The exposure method according to claim 1, wherein,

The maximum speed of the stepwise driving of the stage specified by the second driving characteristic is greater than the maximum speed of the stepwise driving of the stage specified by the first driving characteristic.

5. The exposure method according to claim 1, wherein,

The maximum acceleration of the step drive of the stage specified by the second drive characteristic is greater than the maximum acceleration of the step drive of the stage specified by the first drive characteristic.

6. The exposure method according to claim 1, wherein,

In the first and second steps, a positional displacement of the stage is measured by detecting an alignment mark provided on the substrate held by the stage with an alignment optical system.

7. The exposure method according to claim 1, wherein,

In the first and second steps, a registration mark obtained by exposing the substrate is inspected by a registration inspection device, thereby measuring a positional displacement of the stage.

8. The exposure method according to claim 2, wherein,

The first driving characteristic and the second driving characteristic are driving characteristics that prescribe a speed or acceleration of a step drive of the stage,

In the third step, a difference between the first measurement value and the second measurement value is obtained as the correction value.

9. The exposure method according to claim 2, wherein,

The first driving characteristic and the second driving characteristic are driving characteristics that prescribe a driving direction of step driving of the stage,

In the third step, half of the difference between the first measurement value and the second measurement value is obtained as the correction value.

10. The exposure method according to claim 1, wherein,

In the fourth step, the stage is step-driven while reflecting the correction value obtained in the third step to a measurement value of the position of the stage measured during the step-driving of the stage.

11. The exposure method according to claim 1, wherein,

In the fourth step, the stage is step-driven while reflecting the correction value obtained in the third step to a target position of the stage during step-driving of the stage.

12. The exposure method according to claim 1, wherein,

The exposure method further includes a fifth step of storing the correction value obtained in the third step in association with exposure recipe data for exposing the substrate.

13. The exposure method according to claim 12, wherein,

In the fifth step, the correction value stored in association with the exposure recipe data is updated periodically.

14. An exposure apparatus for exposing a substrate, characterized in that,

The exposure device comprises:

a stage holding the substrate, and

A control unit for controlling exposure processing for exposing the substrate held by the stage,

In the exposure process, the stage is step-driven to expose the substrate held by the stage while correcting the position of the stage by a correction value for correcting the position shift of the stage, which is obtained based on a first measurement value obtained by step-driving the stage holding the substrate in accordance with a first driving characteristic and a second measurement value obtained by step-driving the stage in accordance with a second driving characteristic different from the first driving characteristic, and the position shift of the stage is measured.

15. A measuring method for measuring an object to be measured is characterized in that,

The measuring method comprises the following steps:

a first step of performing step-driving of a stage holding the object to be measured according to a first driving characteristic, and then measuring a positional shift of the stage to obtain a first measurement value;

And a fourth step of measuring the object held by the stage by driving the stage in a step-wise manner while correcting the position of the stage with the correction value obtained in the third step.

16. A method for manufacturing an article, characterized in that,

The method for manufacturing the article comprises the following steps:

a step of exposing a substrate by using the exposure method according to claim 1;

Developing the substrate after exposure, and

And a step of manufacturing an article from the developed substrate.