JP2018077311A - Measurement device, exposure device, and article production method - Google Patents

Abstract

A technique advantageous in terms of measurement accuracy of a surface position of a measurement object is provided. A measuring apparatus causes a measurement light to be incident on a first measurement point of an object at a predetermined incident angle, and receives a measurement light reflected by the object to measure a surface position of the object. A measuring instrument and a second measuring instrument that measures the surface position of the object by causing the measuring light to enter the second measurement point of the object at a predetermined incident angle and receiving the measurement light reflected by the object. Including. The second measuring instrument is arranged at a second measuring point different from the first measuring point so that the measuring light is incident from a direction different from the direction in which the first measuring instrument enters the first measuring point. . [Selection] Figure 3

Description

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

  In recent years, flip chip mounting is increasingly used as semiconductor device mounting. The manufacturing process of a semiconductor device corresponding to flip chip mounting includes a process of forming solder balls on the device. One method for forming solder balls is a plating method. In order to form a solder ball by plating, it is necessary to bring the conductive film formed on the substrate (wafer) into contact with the electrode of the plating apparatus.

  Patent Document 1 discloses a method of peeling a portion of a resist film that is formed on a conductive film in contact with an electrode. When the resist is a negative resist, it is only necessary to prevent light from being applied to the periphery of the wafer during exposure. In this regard, Patent Document 2 discloses a method of arranging a light shielding plate on a wafer during exposure.

Japanese Examined Patent Publication No. 2-51254 US Pat. No. 6,680,774

  As described in Patent Document 2, since exposure is performed with the wafer peripheral portion shielded from light at the time of wafer exposure, a light shielding object is disposed on the wafer at the time of exposure. When exposing a wafer, it is necessary to measure the surface position of the wafer at a predetermined position with a light oblique incidence type measuring device and to correct the wafer surface to the optimum exposure image formation position. However, at the wafer peripheral portion, the light of the oblique incident light is kicked by the light shielding member and cannot be measured, and the focus accuracy can be lowered. This is a problem that may occur if there is a light-shielding object in the peripheral part of the region measured by obliquely incident light regardless of the peripheral part of the wafer.

  An object of this invention is to provide the technique advantageous at the point of the measurement precision of the surface position of a measurement object.

  According to one aspect of the present invention, a measuring apparatus having a plurality of measuring devices for measuring a surface position of an object, wherein the plurality of measuring devices emit a plurality of measurement points in a measurement region of the object. A first measuring instrument for measuring the surface position of the object by receiving the measurement light reflected by the object and receiving the measurement light reflected by the object; The surface position of the object is determined by entering the second measurement point different from the first measurement point among the plurality of measurement points at a predetermined incident angle and receiving the measurement light reflected by the object. A second measuring device that measures the second measuring device from an orientation different from the orientation in which the first measuring device enters the first measuring point at the second measuring point. A measuring device characterized by being arranged to allow measurement light to enter. It is subjected.

  ADVANTAGE OF THE INVENTION According to this invention, the technique advantageous at the point of the measurement precision of the surface position of a measurement object is provided.

1 is a diagram showing a configuration of an exposure apparatus according to an embodiment. FIG. 5 is a view showing an example of a shot layout and alignment marks on a wafer in the embodiment. The figure which shows the structural example of the measuring device in embodiment. The figure which shows the structural example of the measuring device in embodiment. The top view and side view of a wafer in an embodiment. The figure explaining the conventional measuring device. The figure explaining the measurement limit of the wafer by a light-shielding object. The figure explaining the light-shielding area | region by the light-shielding object at the time of using each measuring device. The figure explaining selection of the measuring device in an embodiment. The figure which shows the structural example of the measuring device in embodiment. The figure explaining selection of the measuring device in an embodiment. The figure explaining the shift focus in embodiment. The flowchart which shows the measuring method by the measuring device in embodiment. 6 is a flowchart showing an exposure method by the exposure apparatus in the embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to the following embodiment, The following embodiment shows only the specific example of implementation of this invention. Moreover, not all combinations of features described in the following embodiments are indispensable for solving the problems of the present invention. In each figure, the same reference numerals are assigned to the same members.

<First Embodiment>
FIG. 1 is a view showing the arrangement of an exposure apparatus 100 according to an embodiment to which the measurement apparatus of the present invention is applied. FIG. 2 is a diagram illustrating a shot layout and alignment marks of the wafer 3 as a substrate. In FIG. 1, an exposure apparatus 100 includes a reticle stage 2 that holds a reticle 1 that is an original, a wafer stage 4 that is movable while holding a wafer 3 that is a substrate, and a reticle 1 that is held on the reticle stage 2. And an illumination optical system 5 that illuminates with exposure light. In the periphery of the wafer 3, a light shield 501 is disposed on the outer periphery of the wafer. The exposure apparatus 100 further controls the projection optical system 6 that projects and exposes the reticle pattern image of the reticle 1 illuminated with exposure light onto the wafer 3 held on the wafer stage 4 and the overall operation of the exposure apparatus. And a control unit 20 that performs. The control unit 20 can include, for example, a CPU 21 and a memory 22. The memory 22 stores various control data, an exposure apparatus control program executed by the CPU 21, and the like.

  The exposure apparatus 100 can be, for example, a scanning exposure apparatus (scanning stepper) that exposes the reticle pattern formed on the reticle 1 onto the wafer 3 while moving the reticle 1 and the wafer 3 in synchronization with each other in the scanning direction. The exposure apparatus 100 may be an exposure apparatus (stepper) of a type that fixes the reticle 1 and exposes the reticle pattern onto the wafer 3, but in the present embodiment, the exposure apparatus 100 is described as a scanning exposure apparatus. To do.

  In the following description, the optical axis direction of the projection optical system 6 is the Z-axis direction, and the moving direction (scanning direction) of the reticle 1 and the wafer 3 in the plane perpendicular to the Z-axis direction is the Y-axis direction. A direction perpendicular to the Y-axis direction is taken as an X-axis direction. The rotation directions around the X, Y, and Z axes are the θX, θY, and θZ directions, respectively.

  A predetermined illumination area on the reticle 1 is illuminated with exposure light having a uniform illuminance distribution by the illumination optical system 5. As the light source in the illumination optical system 5, a mercury lamp, a KrF excimer laser, an ArF excimer laser, an F2 laser, or the like can be used. Alternatively, in order to manufacture a finer semiconductor element or the like, the illumination optical system 5 may emit extreme ultraviolet light (Extreme Ultra Violet: EUV light) having a wavelength of several nm to hundred nm.

  The reticle stage 2 can be two-dimensionally moved in a plane perpendicular to the optical axis of the projection optical system 6, that is, an XY plane, and can be slightly rotated in the θZ direction. In the present embodiment, three-axis driving is shown, but any of one-axis driving to six-axis driving may be used. The reticle stage 2 is driven by a reticle stage driving device (not shown) such as a linear motor, and the reticle stage driving device is controlled by the control unit 20. A mirror 7 is provided on the reticle stage 2. Further, an XY-direction laser interferometer 9 for measuring the position of the mirror 7 is provided at a position facing the mirror 7. The two-dimensional position and rotation angle of the reticle 1 on the reticle stage 2 are measured in real time by the laser interferometer 9, and the measurement result is output to the control unit 20. The control unit 20 positions the reticle 1 supported by the reticle stage 2 by driving the reticle stage drive device based on the measurement result of the laser interferometer 9.

  The projection optical system 6 projects and exposes the reticle pattern of the reticle 1 onto the wafer 3 at a predetermined projection magnification β, and is composed of a plurality of optical elements. In the present embodiment, the projection optical system 6 is a reduction projection system having a projection magnification β of, for example, 1/4 or 1/5.

  The wafer stage 4 includes a θZ tilt stage that holds the wafer 3 via a wafer chuck (not shown), an XY stage (not shown) that supports the θZ tilt stage, and a base (not shown) that supports the XY stage. . The wafer stage 4 is driven by a wafer stage driving device (not shown) such as a linear motor. The wafer stage driving device is controlled by the control unit 20. That is, in the present embodiment, the control unit 20 can also function as a drive control unit for the wafer stage. A mirror 8 that moves with the wafer stage 4 is provided on the wafer stage 4. In addition, a laser interferometer 10 for measuring the XY direction and a laser interferometer 12 for measuring the Z direction are provided at positions facing the mirror 8. The position of the wafer stage 4 in the XY direction and θ are measured in real time by the laser interferometer 10, and the measurement result is output to the control unit 20. Further, the position of the wafer stage 4 in the Z direction, θX, θY is measured in real time by the laser interferometer 12, and the measurement result is output to the control unit 20. The wafer stage 4 positions the wafer 3 held on the wafer stage 4 by driving the wafer stage 4 through the wafer stage driving device based on the measurement results of the laser interferometers 10 and 12.

  A reticle alignment detection system 13 is provided in the vicinity of the reticle stage 2. The reticle alignment detection system 13 includes a reticle reference mark (not shown) on the reticle 1 arranged on the reticle stage and a reticle alignment detection system reference mark 17 on the stage reference plate 11 on the wafer stage 4 (see FIG. 2). ) And are detected. The reticle alignment detection system 13 includes a photoelectric conversion element such as a CCD camera, for example, and detects reflected light from the reticle reference mark and the reticle alignment detection system reference mark 17. Based on the signal from the photoelectric conversion element, alignment between the reticle and the wafer is performed. At this time, the relative positional relationship (X, Y, Z) between the reticle and the wafer can be adjusted by adjusting the position and focus of the reticle reference mark and the reticle alignment detection system reference mark 17. The reticle alignment detection system reference mark 17 may be a reflection type or a transmission type. The stage reference plate 11 at the corner of the wafer stage 4 is installed at almost the same height as the surface of the wafer 3.

  The off-axis (OA) detection system 16 uses measurement light as a wafer alignment mark 19 (see FIG. 2) on the wafer 3 as an object to be measured and an OA detection system reference mark 18 on the stage reference plate 11 (see FIG. 2). An irradiator for irradiating the The OA detection system 16 further includes a light receiver that receives reflected light from these marks, and detects the mark positions of the wafer alignment mark 19 and the OA detection system reference mark 18.

  The measuring device 15 as a focus / tilt detection system projects measurement light onto the surface of the wafer 3 that is the object of measurement, and receives the measurement light reflected by the wafer 3, thereby measuring the height direction (Z A plurality of measuring instruments for measuring the position (surface position) of the (direction). FIG. 3 is a diagram illustrating a configuration example of the measuring device 15 including such a plurality of measuring instruments. In the present embodiment, a plurality of measurement points are set in the shot area 505 corresponding to the measurement area. That is, the plurality of measurement points are in the same shot area on the substrate. In the example of FIG. 3, three measurement points 505 a, 505 b, and 505 c are set in the shot area 505. The measuring device 15 includes a plurality of measuring devices 151, 152, and 153 for a plurality of measuring points 505a, 505b, and 505c, respectively. The measurement results of the plurality of measuring instruments 151, 152, 153 are output to the control unit 20 as surface shape data. Here, the measurement device 15 is also controlled by the control unit 20, but the measurement device 15 may include a dedicated control unit. Measuring instrument 151 includes a projector 1511 that projects measurement light onto measurement point 505a, and a light receiver 1512 that receives reflected light. The measuring instrument 152 includes a projector 1521 that projects measurement light onto the measurement point 505b and a light receiver 1522 that receives reflected light. Measuring instrument 153 includes a projector 1531 that projects measurement light onto measurement point 505c, and a light receiver 1532 that receives reflected light. Each of the plurality of measuring instruments 151, 152, and 153 is arranged so that the measurement light is incident on a different measurement point in the shot region 505 from a different direction from the other measurement instruments. That is, the planes formed by the incident light and the reflected light of the measurement light of each of the plurality of measuring instruments 151, 152, and 153 intersect each other. The control unit 20 can function as a selection unit that selects a measuring instrument to be used for measurement from the plurality of measuring instruments 151, 152, and 153.

  Next, details of the measuring instrument 151 will be described with reference to FIG. The projector 1511 can include a condenser lens 402, a pattern plate 403, a lens 404, and a mirror 405. The light receiver 1522 can include a mirror 406, a lens 407, and a CCD 408. The measurement light emitted from the light source 401 is condensed by the condenser lens 402 and illuminates the pattern plate 403. The light transmitted through the slit of the pattern plate 403 is irradiated onto the wafer 3 through the lens 404 and the mirror 405 at a predetermined incident angle. The pattern plate 403 and the wafer 3 form an imaging relationship with respect to the lens 404, and an aerial image of the slit of the pattern plate 403 is formed on the wafer 3. The slit image reflected by the wafer 3 is re-imaged on the CCD 408 by the mirror 406 and the lens 407, and a signal composed of a slit image corresponding to each slit of the pattern plate 403 such as 403i is obtained. By detecting the positional shift of this signal on the CCD, the position of the wafer 3 in the Z direction is measured.

  The configuration of the other measuring instruments 152 and 153 can be the same as that of the measuring instrument 151. In the present embodiment, the configuration in which measurement is performed using the slit of the pattern plate 403 is shown. However, the slit 3 is not configured, and the wafer 3 is directly irradiated with measurement light to measure the position of the wafer 3 in the Z direction. May be. The control unit 20 drives the Z stage based on the measurement results of the plurality of measuring instruments 151, 152, and 153, and adjusts the position (focus position) and tilt angle of the wafer 3 held on the Z stage in the Z-axis direction. Is possible.

  Although FIG. 3 shows an example in which the measuring device 15 has three measuring instruments, the number of measuring instruments is not limited to three. Further, the direction in which each measuring instrument enters the measurement light can be arbitrarily set. In the example of FIG. 3, each of the plurality of measuring devices is arranged so that the measurement light is incident from a different direction from the other measuring devices, but is not limited to a configuration in which all the measuring devices are directed in different directions. . Measuring instruments facing the same direction may be included. That is, it is only necessary that at least one of the plurality of measuring instruments is arranged so that the measuring light is incident from a different direction from the other measuring instruments. In each measuring instrument, the incident angle on the wafer 3 may be common to each measuring instrument or may be set individually. Furthermore, the positions and intervals of measurement points of a plurality of measuring instruments can be set arbitrarily. It is possible to select and measure a measuring device that meets the conditions according to the measurement target.

  Summarizing the above, it can be said that the measuring device 15 in the present embodiment has the following configuration. That is, the measuring device 15 includes a plurality of measuring instruments including at least a first measuring instrument and a second measuring instrument. The first measuring instrument causes measurement light to enter the first measurement point of the object (wafer 3) at a predetermined incident angle, and receives the measurement light reflected by the object, thereby determining the surface position of the object. measure. Further, the second measuring instrument makes the measurement light incident on a second measurement point different from the first measurement point of the target object at a predetermined incident angle, and receives the measurement light reflected by the target object. Measure the surface position of the object. Here, the second measuring instrument is arranged so that the measuring light is incident on the second measuring point from a direction different from the direction in which the first measuring instrument enters the measuring light at the first measuring point.

  Next, control of the measuring device 15 in this embodiment is demonstrated.

  FIG. 5 shows a plan view and a side view of the wafer 3. As shown in FIG. 5, a light shield 501 is mounted on the outer periphery of the wafer 3. Conventionally, a measuring apparatus as a focus / tilt detection system irradiates a plurality of measurement points 504 in a shot area 505 with measurement light 503 from the same direction (for example, a direction along the ZX plane) as shown in FIG. Was. In this case, as shown in the plan view of FIG. 5, a part of the light on the wafer is kicked near the shade 501. The side view of FIG. 5 shows a situation in which the wafer 3 near the light shield 501 is measured with the measurement light 503. The measurement light 503 is incident on the wafer at an incident angle α and reflected. In the side view of FIG. 5, the measurement point is a limit position that can be measured with the measurement light 503 due to the presence of the light shield 501. Therefore, it is not possible to measure outside this measurement point. In FIG. 5, a light shielding region 502 indicates a region where the measurement light 503 is shielded by the light shielding object 501 and cannot be measured. Since all the measurement light 503 is parallel to the ZX plane, the light shielding region 502 is a region as illustrated. In FIG. 6, the measurement light 503 is shown as five light beams. However, if the measurement light 503 is parallel to the ZX plane, the light shielding region 502 that is shielded by one light beam is the same. Note that the light-shielding region 502 can change depending on the position where the measurement device is arranged.

  The measurement limit by the above-described light shield 501 will be specifically described. Consider the case where the coordinates of Y = 0 are measured. A measuring instrument 151 that enters parallel to the ZX plane is compared with a measuring instrument 153 that enters the ZX plane at an angle. FIG. 7 shows the first quadrant of the wafer 3, and a light shielding object 501 is arranged around the wafer. In each of the measuring instruments 151 and 153, the incident angle and the reflection angle to the wafer 3 are set to α (see FIG. 5).

Let R be the radius from the center of the wafer 3 to the light shield 501, and θ be the angle between the ZX plane and the measuring instrument 153 incident at an angle with respect to the ZX plane. In the measuring instrument 151, the measurement limit from the light shielding object 501 is set to L in the XY plane. here,
L ′ = {R ² − (L sin θ) ² } ^1/2 (1)
And

The region Δ where the measurement range is wider than the current state is expressed by the following equation.
Δ = L− {Lcos θ + (R−L ′)} (2)
The measuring device 151 that enters parallel to the ZX plane can measure only up to the measuring point 701. On the other hand, it is possible to measure up to the measurement point 702 with the measuring instrument 153 that enters the ZX plane with an angle. By entering with an angle with respect to the ZX plane, a region that could not be measured so far spreads by Δ in the radial direction of the wafer 3. Specifically, for example, if θ = 60 ° and L = 26 mm, Δ = 11.3 mm, so that it is possible to measure up to 11.3 mm outside in the radial direction.

  Next, the light shielding area by the light shielding object 501 on the wafer 3 when each measuring instrument in the measuring device 15 is used will be described with reference to FIGS. In FIG. 8A, a region 801 is a region that is shielded by the light shield 501 when the wafer 3 is measured using the measuring instrument 152. In FIG. 8B, a region 802 is a region that is shielded by the light shield 501 when the wafer 3 is measured using the measuring instrument 153. Note that, when the wafer 3 is measured using the measuring instrument 151, the area shielded by the light shielding object 501 is as shown as the light shielding area 502 in FIG.

  As described above, as shown in FIGS. 5, 8A, and 8B, the light shielding object 501 is shielded by arranging the measuring instrument that makes the measuring light incident at an angle with respect to the ZX plane. The area changes. The light shielding region is a symmetric region with respect to the ZX plane and a plane of θ + 90 °, where θ is an angle formed with the ZX plane of the measuring instrument.

  With reference to FIG. 9, the selection of the measuring instrument in this embodiment is demonstrated. FIG. 9 shows a light shielding area 502 when the measuring instrument 151 is used, similar to FIG. When only the measuring instrument 151 is used as in the prior art, the measurement points in the light shielding area 502 cannot be measured. On the other hand, in the present embodiment, the measurement in the light shielding area 502 is selected by selecting a measuring instrument to be used from the plurality of measuring instruments 151, 152, 153 according to the position of the measurement point in the shot area that is the measurement area. Point measurement is also possible. In the present embodiment, the measurement points 111, 113, 114, 116, and 119 located at the upper left of the shot area are measured by selecting the measuring instrument 152. Measurement points 112, 115, 117, 118 and 120 located on the upper right side of the shot area are measured by selecting the measuring instrument 153.

  Hereinafter, the substrate surface position measuring method (S10) by the measuring device 15 will be described with reference to the flowchart of FIG. The program corresponding to this flowchart is stored in the memory 22 and executed by the CPU 21.

  First, in S11, a measuring instrument to be used is selected from a plurality of measuring instruments 151, 152, and 153 according to the position of the measurement point to be measured in the target shot area. For this selection, for example, a lookup table (LUT), which is information defining the correspondence between each measurement point in each shot area of the wafer and the identification information of the measuring instrument to be used, is acquired in advance, and this LUT is referred to. Is done. Next, in step S <b> 12, the wafer 3 is driven by the wafer stage 4 so that the position of the target measurement point in the target shot area comes to the measurement position of the measurement device 15. Next, in S13, the surface position (height) of the wafer 3 at the measurement point is measured. Thereafter, in S14, it is determined whether there is a next measurement point to be measured in the shot area. If there is a next measurement point to be measured in the shot area, the process returns to S11 and the process is repeated for the next measurement point. For example, when three measurement points in one shot area are set, three measuring devices are sequentially selected in S11 so that measurement of these three measurement points is performed. If all the measurement points in the shot area have been measured, the process proceeds to S15.

  For example, when five measurement points in one shot area are set and, for example, when measurement is successfully performed at three measurement points, measurement of the shot area is completed in S14. The process may proceed to S15. Tilt can be calculated if at least three points are measured within one shot area.

  Alternatively, when the reflected light at one measurement point obtained in S13 is kicked by the light blocking object, the reflected light does not reach the light receiver sufficiently. For example, when the light amount of the measurement light received by the light receiver is equal to or less than the threshold value, the control unit 20 determines that the detection error is caused by the reflected light being kicked by the light shielding object. If such a detection error occurs, the process may return to S11 in order to measure other measurement points with other measuring instruments (except when measurement of all measurement points is completed) in S14.

  If there is an unmeasured shot area in S15 (YES in S15), the process returns to S11 and the process is repeated for the next shot area. When the processing is completed for all shot areas, the measurement is terminated, and the measurement result is stored in the memory 22 as surface shape data.

  As described above, the measurement apparatus includes a plurality of measurement units each having different azimuths for irradiating measurement light, and the measurement direction can be changed by selecting a measurement unit according to the position of the measurement point. According to this embodiment, even if a light shielding object is provided around the measurement object (substrate), measurement points in the light shielding region by the light shielding object can be measured, and the measurement accuracy of the surface position of the substrate surface can be improved. Can be improved. Thereby, in an exposure apparatus using such a surface position measuring apparatus, higher focus accuracy is realized, and an improvement in yield can be achieved.

Second Embodiment
An example of arrangement of each measuring instrument in the measuring apparatus according to the second embodiment is shown in FIGS. FIG. 3 shows an example in which the number of measurement points in one shot area is three. However, in FIGS. 10A and 10B, the number of measurement points is set to the same conditions as in the conventional example shown in FIG. Has 5 points. In FIG. 10A, the incident azimuths of the measurement light with respect to each measurement point are different. The measuring device includes a plurality of measuring devices 601 to 605 that can be controlled independently. Measurement light from each measuring instrument is incident on the wafer at an angle α and reflected. FIG. 10B shows a detailed arrangement example of the measuring instruments 601 to 605. The measuring instrument 601 includes a projector 6011 and a light receiver 6012. The measuring instrument 602 includes a projector 6021 and a light receiver 6022. The measuring device 603 includes a projector 6031 and a light receiver 6032. The measuring instrument 604 includes a projector 6041 and a light receiver 6042. The measuring instrument 605 includes a projector 6051 and a light receiver 6052. The measuring instruments 601 to 605 are independent of each other, but may be configured in a common optical system or may be configured in different optical systems.

  FIG. 11 is a diagram for explaining selection of the measuring instruments 601 to 605 shown in FIG. In FIG. 11, only the first quadrant of the wafer 3 is shown for explanation. As in the first embodiment, a light shield 501 is mounted on the outer periphery of the wafer. In FIG. 11, when only the measuring instrument 601 is used, all the measurement points 71 to 77 in the light shielding area 502 cannot be measured. On the other hand, the measurement points 71 to 77 can be measured by selectively using the measuring instruments 601 to 605 shown in FIG. Since the measurement area of each measuring instrument is the same as that described in the first embodiment, a description thereof will be omitted.

  Specifically, the measurement points 71, 73, and 74 located on the lower right side of the shot area are measured by selecting the measuring device 605. The measurement points 72, 75, and 77 located in the upper left of the shot area are measured by selecting the measuring device 603. The measurement point 76 located at the lower left of the shot area is measured by selecting the measuring device 604. The measurement point 78 located on the upper right side of the shot area is measured by selecting the measuring device 602. As described above, a measuring instrument to be used is selected from a plurality of measuring instruments according to the position of each measuring point in the shot region. Thereby, even if there is a light blocking object on the wafer, the measurement light can be applied to the measurement point without being kicked by the light blocking object from the plurality of measuring instruments, and the measurement accuracy can be improved.

  Although FIG. 11 shows only the first quadrant of the wafer, the same applies to the second to fourth quadrants. In the first and second embodiments, one measurement point is measured by one measuring instrument. However, the present invention is not limited to this, and a plurality of measuring points measured by one measuring instrument may be used.

<Third Embodiment>
FIG. 12 shows an embodiment in which shift focus is performed using the measuring instruments 601 to 605. According to the method of the present embodiment, the measurement accuracy can be further increased with respect to the method described in FIG. In FIG. 12, in order to measure the shot area 82, first, the shot area 82 is moved below the measuring instruments 601 to 605. In this state, by selecting the measuring instrument 605, it is possible to measure only the measurement point 74 located at the lower right of the shot area 82. In this state, measurement cannot be performed by the measuring instrument 602 at the measurement point 79. However, if the wafer 3 is moved and shift focus is performed to move the measurement point 79 to the position of the measuring instrument 603 or measuring instrument 605, the measuring instrument 603 or the measuring instrument 605 can perform measurement. By performing the shift focus in this way, it is possible to further improve the measurement accuracy. According to this method, the measurement point 78 of the shot area 81, the measurement points 80 and 85 of the shot area 83, and the measurement point 84 of the shot area 86 can be measured by selecting the measuring instrument 603 or the measuring instrument 605.

  From the viewpoint of shortening the measurement time, it is desirable to select a measuring instrument to be used so that the movement amount of the wafer 3 by the shift focus becomes small. Therefore, in the present embodiment, for example, when measuring the measurement point 79, the following control is performed. First, the wafer stage 4 is driven so that the center of the shot area 82 comes to the position of the measuring instrument 601, and measurement of the measurement point located at the center of the shot area 82 is performed. Then, the movement destination in the shift focus for measuring the measurement point 79 is determined. The destination candidate is the position of the measuring instrument 603 or measuring instrument 605 as described above. At this time, the measuring instrument closer to the distance from the current position (center of the shot area 82) to the measuring instrument 603 and the distance to the measuring instrument 605 is selected. In the example of FIG. 12, the measuring instrument 603 is selected because the measuring instrument 603 is closer to the center of the shot area than the measuring instrument 605 from the shape of the shot area 82. Therefore, the control unit 20 selects a measurement point where the movement amount of the wafer 3 is small among the plurality of measurement points, and the selected measurement point is positioned at a position where measurement light is incident by the selected measurement unit. The wafer 3 (that is, the wafer stage 4) is moved. Note that this method is not limited to the case of performing the shift focus, and the measurement may be performed by selecting a measuring instrument so as to reduce the moving amount of the wafer stage 4.

  In FIG. 12, only the first quadrant of the wafer is described to describe the present method. However, the present method can be similarly applied to the second to fourth quadrants. Note that the instrument you choose will change.

  Next, a substrate exposure method by the exposure apparatus 100 will be described with reference to the flowchart of FIG. The program corresponding to this flowchart is stored in the memory 22 and executed by the CPU 21.

  First, in S21, the wafer 3 is carried into the exposure apparatus 100, and in S22, the wafer 3 is aligned by the OA detection system 16. Next, in step S <b> 10, the wafer surface position measurement described with reference to FIG. 13 is performed by the measurement device 15, and surface shape data as a measurement result is stored in the memory 22. Next, in S <b> 23, the wafer 3 is positioned by the wafer stage 4 at a position for starting scanning of the shot area to be exposed. At that time, the position (focus) of the wafer 3 in the Z direction is reduced by the wafer stage 4 based on the surface shape data of the wafer 3 so that the amount of deviation of the surface position of the wafer 3 from the image plane of the projection optical system 6 is reduced. ) And tilt (tilt) are controlled. In S24, the shot area to be exposed is subjected to scanning exposure. In this scanning exposure, the control unit 20 controls the wafer stage 4 to control the position (focus) and tilt (tilt) of the wafer 3 in the Z direction so that the amount of deviation from the image plane is reduced. Thereby, in the scanning exposure of each shot area, the surface of the wafer 3 can coincide with the image plane of the projection optical system 6 in synchronization with the scanning of the wafer 3. In S25, the control unit 20 determines whether there is an unexposed shot area. If there is an unexposed shot area, the process returns to S10 and the process is repeated for the next shot area. When the exposure of all the shot areas is completed, the wafer 3 is unloaded from the exposure apparatus 100 in S26.

<Embodiment of article manufacturing method>
The article manufacturing method according to the embodiment of the present invention is suitable for manufacturing an article such as a micro device such as a semiconductor device or an element having a fine structure. In the article manufacturing method of the present embodiment, a latent image pattern is formed on the photosensitive agent applied to the substrate using the above-described exposure apparatus (a step of exposing the substrate), and the latent image pattern is formed in this step. Developing the substrate. Further, the manufacturing method includes other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, and the like). The article manufacturing method of this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

15: Measuring device, 151, 152, 153: Measuring instrument, 1511, 1521, 1531: Light projector, 1512, 1522, 1532: Light receiver

Claims (11)

A measuring device having a plurality of measuring instruments for measuring the surface position of an object,
The plurality of measuring instruments are:
A surface of the object is obtained by causing measurement light to enter a first measurement point of a plurality of measurement points in the measurement region of the object at a predetermined incident angle and receiving the measurement light reflected by the object. A first measuring instrument for measuring the position;
The measurement light is incident on a second measurement point different from the first measurement point among the plurality of measurement points at a predetermined incident angle, and the measurement light reflected by the object is received to receive the measurement light of the object. A second measuring instrument for measuring the surface position;
Including
The second measuring device is disposed at the second measurement point so that the measurement light is incident from a different direction from the direction in which the first measuring device is incident on the first measurement point. A measuring device characterized by that.   The measuring apparatus according to claim 1, further comprising a selection unit that selects a measuring instrument to be used among the plurality of measuring instruments.   The said selection part selects the measuring instrument to be used according to the position in the said measurement area | region of the measurement point made into a measurement object among the said several measurement points in the measurement area | region of the said object. 2. The measuring device according to 2.   The selection unit selects the measuring instrument to be used based on information defining a correspondence relationship between each of the plurality of measuring points and a measuring instrument to be used among the plurality of measuring instruments. The measuring device according to claim 2. The plurality of measuring instruments includes at least three measuring instruments;
The plurality of measurement points include at least three measurement points corresponding to the at least three measuring instruments,
5. The measuring device according to claim 2, wherein the selection unit sequentially selects the at least three measuring devices so that the measurement of the at least three measuring points is performed. .   The selection unit further selects another measurement unit in the selected measurement unit when a detection error occurs due to a light amount of the received measurement light being equal to or less than a threshold value. 5. The measuring device according to any one of items 4 to 4.   The drive control unit for moving the object so that one of the plurality of measurement points is positioned at a position where the measurement light is incident by the measurement unit selected by the selection unit. The measuring device according to any one of 2 to 6.   The drive control unit selects a measurement point having a small amount to be moved for measurement of the object from the plurality of measurement points, and the selected measurement point is selected by the measurement unit selected by the selection unit. The measurement apparatus according to claim 7, wherein the object is moved so as to be located at a position where the measurement light is incident. An exposure apparatus that projects an original pattern onto a substrate by a projection optical system and exposes the substrate,
The measurement apparatus according to any one of claims 1 to 8, which is arranged to measure a surface position of the substrate;
A control unit that controls the position of the substrate based on the result of measurement by the measurement device so that the amount of deviation of the surface position from the image plane of the projection optical system is reduced;
An exposure apparatus comprising:   The exposure apparatus according to claim 9, wherein the first measurement point and the second measurement point are in the same shot area on the substrate. A step of exposing the substrate using the exposure apparatus according to claim 9 or 10;
Developing the exposed substrate;
A method for producing an article, comprising:

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