Exposure apparatus and article manufacturing method

Abstract

An exposure apparatus is disclosed for exposing multiple projection areas on a substrate. The apparatus includes a projection optics system, a drive mechanism configured to drive the substrate, a detector configured to detect the surface height of the substrate, and a controller configured to control the drive mechanism based on the output of the detector. The projection optics system is configured to project a pattern of a master image onto the exposure areas in the image plane of the projection optics system. The detection area of ​​the detector is larger than the exposure areas. The controller is configured to control the drive mechanism to drive the substrate, based on the output of the detector obtained when a first projection area among the multiple projection areas is positioned in the exposure areas, to expose a second projection area among the multiple projection areas.

Description

Technical Field

[0001] The present invention relates to an exposure device and an article manufacturing method. Prior Art

[0002] In an exposure device, the shot region on a substrate can be exposed after measuring its height and adjusting the substrate height based on the measurement results. Japanese Patent Laid-Open No. 2016-206654 describes measuring the heights of multiple measurement points in the shot region on a substrate (positions along the optical axis of a reduced projection lens system) and adjusting the substrate height and tilt based on the measurement results.

[0003] In exposure equipment, the process of measuring the height of the projected area on the substrate after it falls into the exposure area of ​​the projection optical system (the exposure area is the area irradiated with light by the projection optical system during exposure) limits throughput. Summary of the Invention

[0004] The present invention provides techniques that facilitate increased throughput.

[0005] A first aspect of the present invention provides an exposure device for exposing multiple projection areas on a substrate, the exposure device comprising: a projection optical system; a drive mechanism configured to drive the substrate; a detector configured to detect the surface height of the substrate; and a controller configured to control the drive mechanism based on the output of the detector, wherein the projection optical system is configured to project a pattern of an original onto an exposure area in an image plane of the projection optical system, the detection area of ​​the detector is larger than the exposure area, and the controller is configured to control the drive mechanism to drive the substrate based on the output of the detector obtained when a first projection area among the multiple projection areas is arranged in the exposure area, so as to expose a second projection area among the multiple projection areas.

[0006] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. Simple diagram description

[0007] [FIG. 1] is a diagram schematically showing an example of the arrangement of an exposure apparatus according to an embodiment of the present disclosure;

[0008] [Figure 2] is a diagram showing an example of the arrangement of the detector;

[0009] [FIG. 3] is a diagram showing an exemplary geometric relationship between an image sensor, a detection area, and a pattern image;

[0010] [Figure 4] is a diagram for exemplifying the operation according to the embodiment;

[0011] [Figure 5] is a diagram for explaining the operation of the first modification;

[0012] [Fig. 6] is a diagram for explaining the operation of the second modification; and

[0013] [ Fig. 7 ] is a diagram for explaining the operation of the third modification example. Implementation Method

[0014] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the claimed invention. While various features are described in the embodiments, the present invention is not limited to requiring all of these features, and multiple such features may be appropriately combined. Furthermore, identical reference numerals are assigned to identical or similar configurations in the accompanying drawings, and redundant descriptions thereof are omitted.

[0015] FIG1 schematically illustrates an example arrangement of an exposure apparatus EX according to an embodiment of the present disclosure. The exposure apparatus EX can be configured to expose multiple projection areas on a substrate 405. The exposure apparatus EX may include a projection optical system 404, a drive mechanism (substrate drive mechanism) 412 that drives the substrate 405, a detector 100 that detects the surface height of the substrate 405, and a controller 410 that controls the drive mechanism 412 based on the output of the detector 100. The projection optical system 404 can be configured to project a pattern of the original plate 402 onto an exposure area ER within the image plane of the projection optical system 404. The exposure area ER is the area illuminated by the projection optical system 404 with exposure light. If the exposure apparatus EX is configured as a stepper, when the projection areas on the substrate 405 are arranged within the exposure area ER, the extent of the projection areas can coincide with the extent of the exposure area ER. If the exposure apparatus EX is configured as a scanner, the exposure area ER is a slit-shaped area, and when the substrate 405 is scanned about the exposure area ER, the exposure areas on the substrate 405 are exposed. The detection area, which is the field of view of the detector 100, is larger than the exposure area ER.

[0016] Based on the output of the detector 100 obtained when a first projection area among the multiple projection areas on the substrate 405 is positioned in the exposure area ER, the controller 410 can control the drive mechanism 412 to drive the substrate to expose a second projection area among the multiple projection areas. Note that the terms "first projection area" and "second projection area" are merely terms used to distinguish different projection areas from one another. Based on the output of the detector 100 obtained when the first projection area is positioned in the exposure area ER, the controller 410 can control the drive mechanism 412 to drive the substrate 405 when the second projection area is moved to the exposure area ER. Here, driving the substrate may include driving to align the second projection area (its surface) with the image plane of the projection optical system 404 (driving the substrate in a direction parallel to the optical axis of the projection optical system 404).

[0017] For example, the controller 410 may control the drive mechanism 412 to drive the substrate 405 based on the output of the detector 100 obtained when the first shot region is exposed in the exposure region ER, thereby moving the second shot region to the exposure region ER. Alternatively, the controller 410 may control the drive mechanism 412 to drive the substrate based on the output of the detector 100 obtained during the period from when the first shot region is placed in the exposure region ER to when the first shot region is exposed, thereby moving the second shot region to the exposure region ER.

[0018] The controller 410 can be formed, for example, from a PLD (Programmable Logic Device) such as an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), a general-purpose or dedicated computer with a program installed, or a combination of all or some of these components. The exposure apparatus EX can include a substrate stage 406 including a substrate chuck for holding a substrate 405. The drive mechanism 412 can drive the substrate 405 by driving the substrate stage 406.

[0019] In this specification and the drawings, directions are specified in an XYZ coordinate system. The optical axis AX of the projection optical system 404 is parallel to the Z axis. The optical axis AX and the Z axis are generally parallel to the vertical direction. The drive mechanism 412 can drive and position the substrate 405 relative to six axes: the X axis, the Y axis, the Z axis, rotation about the X axis (θX), rotation about the Y axis (θY), and rotation about the Z axis (θZ). The exposure apparatus EX may include a measuring device 407 for measuring the position and posture of the substrate stage 406. The measuring device 407 may be, for example, a laser interferometer. The measuring device 407 may be configured to apply a laser beam to a reflector 411 provided on the substrate stage 406 and detect displacement of the substrate stage 406 using the laser beam reflected by the reflector 411.

[0020] The exposure apparatus EX may further include an illumination optical system 401 for illuminating the original plate 402 and an original plate drive mechanism 403 for driving the original plate 402. The illumination optical system 401 may uniformly illuminate the original plate 402 using exposure light emitted from a light source (not shown). For example, an ultrahigh-pressure mercury lamp (g-ray lamp or i-ray lamp), a KrF excimer laser, an ArF excimer laser, an F2 laser, or the like may be used as the exposure light. Alternatively, extreme ultraviolet light (EUV light) having a wavelength of several to several hundred nanometers may be used as the exposure light in order to manufacture smaller semiconductor devices.

[0021] Based on the output of the detector 100, the controller 410 can control the drive mechanism 412 to align the projection area to be exposed on the substrate 405 (more specifically, for example, the surface of the projection area) with the image plane of the projection optical system 404. This control can include controlling the surface height (position in the Z-axis direction) and inclination (θX and θY) of the substrate 405. The controller 410 can also control the optical elements of the projection optical system 404 to align the projection area to be exposed on the substrate 405 with the image plane of the projection optical system 404.

[0022] FIG2 shows an example arrangement of detector 100. Detector 100 may include a projection unit 110 and a light receiving unit 120. Projection unit 110 may be configured to obliquely project a pattern onto the surface of substrate 405, serving as a projection target. Projection unit 110 may include, for example, a light source 111, a pattern portion 112 including a two-dimensionally arranged pattern, and a projection optical system 113 for projecting the pattern of pattern portion 112 onto substrate 405. Note that depending on the type of light source 111 and the distance between pattern portion 112 and substrate 405, projection optical system 113 may not necessarily be provided.

[0023] The light receiving unit 120 may include an image sensor 121 and an imaging optical system 122. The imaging optical system 122 forms an image of the pattern projected by the projection unit 110 onto the substrate 405 on the image sensor 121. FIG3 exemplarily illustrates the image sensor 121, the detection area 201, and the pattern image 151 formed on the image sensing surface of the image sensor 121 through the imaging optical system 122. The detection area 201 is the field of view of the detector 100 and is larger than the exposure area ER. The controller 410 processes the image captured in the detection area 201 to obtain the height or height distribution of the area corresponding to the detection area 201 on the entire surface of the substrate 405.

[0024] If the height of the surface of substrate 405, serving as the projection target, fluctuates, the pattern image 151 fluctuates accordingly. Controller 410 can determine the surface height of substrate 405 based on the fluctuations in pattern image 151 captured by image sensor 121. By processing images of any region within detection area 201 of image sensor 121 (corresponding to any region on the surface of substrate 405), controller 410 can detect the height of any region on the surface of substrate 405. Image sensor 121 can be formed, for example, by a CMOS image sensor, a CCD image sensor, a photodiode array, or the like.

[0025] The pattern portion 112 and the surface of the substrate 405 can be arranged in a Scheimpflug optical relationship using the projection optical system 113. This Scheimpflug optical relationship allows the entire area of ​​the pattern portion 112 to be focused on the substrate 405, improving measurement accuracy. Furthermore, the Scheimpflug optical system allows the main direction defining the exposure sequence in the exposure apparatus EX to be aligned with the projection direction of the pattern portion 112. This reduces the size of the pattern image captured by the image sensor 121, allowing the inspection area 201 to be configured to include the adjacent projection area to be exposed next. In the example shown in the figure, the main direction is the Y-axis. Typically, the exposure apparatus EX sequentially exposes multiple projection areas arranged in the main direction, and then sequentially exposes multiple projection areas arranged in adjacent columns.

[0026] 4 exemplarily shows a detection area 501 (corresponding to the detection area 201), a pattern image 500 (corresponding to the pattern image 151), and projection areas 503, 504, and 505. Projection areas 503, 504, and 505 show examples of multiple projection areas along the main direction.

[0027] When the first projection area 504 is positioned in the exposure region ER, the detector 100 can be controlled to capture and output an image of the second projection area 503 or 505 adjacent to the first projection area 504. The second projection area 503 or 505 can be the projection area to be exposed immediately after the first projection area 504, or the projection area to be exposed after the first projection area 504 has been exposed. The controller 410 can control the drive mechanism 412 to drive the substrate 405 to expose the second projection area 503 or 505 based on the output of the detector 100 obtained when the first projection area 504 is positioned in the exposure region ER. Alternatively, the controller 410 can control the drive mechanism 412 to drive the substrate 405 to move the second projection area 503 or 505 to the exposure region ER based on the output of the detector 100 obtained when the first projection area 504 is positioned in the exposure region ER.

[0028] From another perspective, the controller 410 can control the drive mechanism 412 to drive the substrate 405 based on the output of the detector 100 obtained when the first projection area 504 is exposed in the exposure area ER, so as to expose the second projection area 503 or 505. Alternatively, the controller 410 can control the drive mechanism 412 to drive the substrate 405 based on the output of the detector 100 obtained when the first projection area 504 is exposed in the exposure area ER, so as to move the second projection area 503 or 505 to the exposure area ER.

[0029] From another perspective, the controller 410 may control the drive mechanism 412 to drive the substrate 405 based on the output of the detector 100 obtained during the period from when the first projection area 504 is arranged in the exposure area ER to when the first projection area 504 is exposed, so as to expose the second projection area 503 or 505. Alternatively, the controller 410 may control the drive mechanism 412 to drive the substrate 405 based on the output of the detector 100 obtained during the period from when the first projection area 504 is arranged in the exposure area ER to when the first projection area 504 is exposed, so as to move the second projection area 503 or 505 to the exposure area ER.

[0030] When the first projection area is arranged in the exposure area ER, the entire second projection area preferably falls within the detection area 501, but only a portion of the second projection area may fall within the detection area 501. In this case, the height or height distribution of the portion of the second projection area is detected using the detector 100, and the controller 410 can control the drive mechanism 412 to drive the substrate 405 based on the detection result to expose the second projection area.

[0031] In this example, while first projection area 504 is positioned within exposure area ER, detector 100 is used to detect the height or height distribution of second projection area 503. After exposing first projection area 504, controller 410 can then control drive mechanism 412 based on the detection results to align the surface of second projection area 503 with the image plane of projection optical system 404 while simultaneously positioning second projection area 503 within exposure area ER. This shortens the time required to begin exposure of second projection area 503 after exposure of first projection area 504, thereby improving throughput.

[0032] A first modification will be described with reference to FIG5 . In the first modification, the controller 410 detects the height of a first portion 601 of a second projection area 605 on the substrate 405 based on the output of the detector 100 obtained when the first projection area 604 on the substrate 405 is arranged in the exposure area ER. After the second projection area 605 moves to the exposure area ER, the controller 410 detects the height of a second portion 608 of the second projection area 605 based on the output of the detector 100. The controller 410 then controls the drive mechanism 412 to drive the substrate 405 based on the heights of the first portion 601 and the second portion 608, so that the second projection area 605 (its surface) coincides with the image plane of the projection optical system 404. Here, the second portion 608 may be the portion obtained by excluding an exclusion area 607 corresponding to the first portion 601 from the entire second projection area 605. The exclusion area 607 may be the same as the first portion 601, or it may be smaller than the first portion 601, such that the first portion 601 and the second portion 608 partially overlap.

[0033] Compared to conventional methods, according to the first modification, the amount of data processing required to detect the height of the second projection area 605 after moving the second projection area 605 to the exposure area ER can be reduced by an amount corresponding to the exclusion area 607. Data processing can include, for example, data transmission from the detector 100 to the controller 410 and calculations in the controller 410. Therefore, compared to conventional methods, throughput can be improved.

[0034] A second modification will be described with reference to FIG6 . Controller 410 detects the height of first portion 703, which is part of second shot region 702, as a first height based on the output of detector 100 obtained when first shot region 701 is positioned in exposure region ER. Here, second shot region 702 may be a shot region to be exposed immediately after shot region 701, among shot regions 702, 705, 706, and 707 adjacent to shot region 701. After second shot region 702 moves to exposure region ER, controller 410 detects the height of the entire second shot region 702 as a second height based on the output of detector 100. Furthermore, controller 410 stores the difference between the first and second heights as an offset.

[0035] When a second projection area corresponding to the second projection area 702 among the plurality of projection areas on another substrate is moved to the exposure area ER, the controller 410 controls the drive mechanism 412 to drive the substrate based on the height difference of the first portion of the second projection area on the other substrate. For example, when the second projection area on the other substrate is moved to the exposure area ER, the controller 410 can align the second projection area on the other substrate with the image plane of the projection optical system 404 based on a value obtained by correcting the height of the first portion of the second projection area on the other substrate using the difference.

[0036] For example, when processing at least one leading substrate in a batch, the difference (offset) can be measured. For subsequent substrates, the height of the first portion, which is part of the second shot area, can be determined based on the output of detector 100 obtained when the first shot area is positioned in exposure area ER. Then, when the second shot area is moved to exposure area ER, controller 410 can control the drive mechanism 412 to drive substrate 405 based on the height of the first portion of the second shot area and the difference. Therefore, the second modification is advantageous in terms of improving focusing accuracy and increasing throughput.

[0037] A third modification will be described with reference to FIG7 . The first projection area 800 and a first portion 803, which is part of the second projection area 802, can fall within the detection area 801 of the detector 100. The controller 410 detects the height of the first portion 803 of the second projection area 802 based on the output of the detector 100 obtained when the first projection area 800 on the substrate 405 is arranged in the exposure area ER. When the second projection area 802 is moved to the exposure area ER, the controller 410 controls the drive mechanism 412 based on the height of the first portion 803 and the height difference between the first projection area 800 and the second projection area 802, obtained based on pre-registered information. This control can be performed so that the second projection area 802 is aligned with the image plane of the projection optical system 404. The height difference can be obtained using at least one leading substrate from a batch.

[0038] Various methods can be used to control the drive of the substrate based on the height (a) of the first portion 803 and the height difference (b) between the projection area 800 and the area 802. For example, the following method is effective: a weight for the height (a) of the first portion 803 and a weight for the height difference (b) are determined based on actual exposure results, and the drive of the substrate is controlled based on a weighted average of the height (a) of the first portion 803 and the height difference (b).

[0039] The following describes a method for manufacturing an article (such as a semiconductor IC device, liquid crystal display device, or MEMS) using the aforementioned exposure apparatus. The article is manufactured using the exposure apparatus through the steps of exposing a substrate (such as a wafer or glass substrate) coated with a photosensitizer, developing the substrate (photosensitizer), and processing the developed substrate through other known steps. These other known steps include etching, resist removal, dicing, bonding, and packaging. This method can produce higher-quality articles than conventional methods.

[0040] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments and the scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

[0041] 100: Detector 110: Projection unit 111: Light Source 112: Pattern part 113: Projection Optical System 120: Light receiving unit 121: Image sensor 122: Imaging optical system 151: Pattern Image 201: Detection area 401: Illumination optical system 402: Original 403: Original drive mechanism 404: Projection optical system 405:Substrate 406:Substrate table 407: Measuring device 410: Controller 411:Reflector 412: driving mechanism 500: Pattern Image 501: Detection area 503: Projection Area 504: Projection area 505: Projection area 601: Part 1 604: First projection area 605: Second projection area 607: Excluded area 608: Part 2 701: Projection Area 702: Second projection area 703: Part 1 705: Projection Area 706: Projection Area 707: Projection Area 800: Projection area 801: Detection area 802: Second projection area 803: Part 1

Claims

1. An exposure apparatus for exposing a plurality of projection areas on a substrate, the exposure apparatus comprising: Projection optical system; A drive mechanism configured to drive the substrate; A detector configured to detect the surface height of the substrate; and a controller configured to control the drive mechanism based on the output of the detector, wherein the projection optics system is configured to project the original pattern onto an exposure area in the image plane of the projection optics system, the detection area of ​​the detector is larger than the exposure area, and the controller is configured to control the drive mechanism to drive the substrate to expose the second projection area based on the output of the detector obtained when (i) a first projection area in the plurality of projection areas is arranged in the exposure area, and (ii) at least a portion of the first projection area and the second projection area in the plurality of projection areas are arranged in the detection area.

2. The exposure equipment as requested in item 1, wherein, The controller is configured to control the drive mechanism to drive the substrate based on the output of the detector obtained when the first projection area is arranged in the exposure area, so as to move the second projection area to the exposure area.

3. The exposure equipment as requested in item 1, wherein, The controller is configured to control the drive mechanism to drive the substrate based on the output of the detector obtained when the first projection area is exposed in the exposure area, so as to move the second projection area to the exposure area.

4. The exposure equipment as requested in item 1, wherein, The controller is configured to control the drive mechanism to drive the substrate based on the output of the detector obtained during the period from the placement of the first projection area in the exposure area to the exposure of the first projection area, so as to move the second projection area to the exposure area.

5. The exposure equipment as requested in item 1, wherein, The second projection area is the projection area that is to be exposed immediately following the first projection area.

6. The exposure equipment as requested in item 1, wherein, The controller is configured to control the drive mechanism to drive the substrate relative to the optical axis of the projection optics system based on the output of the detector obtained when the first projection area is arranged in the exposure area, so as to move the second projection area to the exposure area.

7. The exposure equipment as requested in item 1, wherein, The controller is configured to detect the height of at least a portion of the second projection area based on the output of the detector obtained when (i) the first projection area is arranged in the exposure area and (ii) the first projection area and at least a portion of the second projection area are arranged in the detection area, and the controller is configured to control the driving mechanism to drive the substrate based on the height of the at least a portion of the second projection area to move the second projection area to the exposure area.

8. The exposure equipment as requested in item 1, wherein, The controller is configured to detect the height of at least a portion of the second projection area based on the output of the detector obtained when (i) the first projection area is arranged in the exposure area and (ii) the first projection area and at least a portion of the second projection area are arranged in the detection area, and after the second projection area moves to the exposure area, the controller detects the height of the second portion of the second projection area based on the output of the detector, and controls the drive mechanism to drive the substrate based on the height of the at least a portion of the second projection area and the height of the second portion of the second projection area.

9. The exposure equipment as requested in item 1, wherein, The controller is configured to detect the height of at least a portion of the second projection area as a first height based on the output of the detector obtained when the first projection area is arranged in the exposure area. After the second projection area is moved to the exposure area, the controller detects the height of the entire second projection area as a second height based on the output of the detector. The controller is configured to store the difference between the first height and the second height. In order to move a second projection area corresponding to the second projection area on the second projection area on the first substrate from a plurality of projection areas on the other substrate to the exposure area, the controller is configured to control the driving mechanism to drive the substrate based on the height of at least a portion of the second projection area on the other substrate and the difference.

10. The exposure equipment as requested in item 1, wherein, The controller is configured to detect the height of at least a portion of the second projection area based on the output of the detector obtained when (i) the first projection area is arranged in the exposure area and (ii) at least a portion of the first projection area and the second projection area are arranged in the detection area, and in order to move the second projection area to the exposure area, the controller is configured to control the drive mechanism to drive the substrate based on the height of at least a portion of the second projection area and the height difference between the first projection area and the second projection area obtained based on pre-registered information.

11. The exposure equipment as described in request item 10, wherein, The height difference is obtained using at least one leading substrate from a batch.

12. A method for manufacturing an article, comprising: Expose the substrate using the exposure equipment described in any of claims 1 to 11; Develop the substrate that has undergone this exposure; And to obtain an article by processing the substrate that has undergone the development.

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