JP2010251409A - Exposure method, exposure apparatus, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure method and apparatus, and a device manufacturing method, capable of improving throughput. <P>SOLUTION: The exposure method includes a step of radiating exposure light to a pattern arranged on a first surface, a step of radiating the exposure light, having passed through the pattern, to a substrate arranged on a second surface, a step of detecting first illuminance of the exposure light on the upper stream side of the optical path of the exposure light than the second surface, a step of detecting second illuminance of the exposure light on the second surface, a step of making the first illuminance to be corresponded to the second illuminance, and a step of adjusting the second illuminance based on the first illuminance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an exposure method, an exposure apparatus, and a device manufacturing method for irradiating a substrate with exposure light via a projection optical system and exposing the substrate.

  When manufacturing a semiconductor element or a liquid crystal display element, a pattern image of a mask (reticle, photomask, etc.) is stepped and applied to each shot area on a plate (glass plate, semiconductor wafer, etc.) coated with a photoresist. A projection exposure apparatus (stepper) that performs batch exposure using the repeat method is used.

  In recent years, instead of using one large projection optical system, a plurality of small partial projection optical systems are arranged in a plurality of rows at predetermined intervals along the scanning direction. A so-called multi-lens type exposure apparatus that projects and exposes an image on a plate has been proposed (see, for example, Patent Document 1).

  In such a multi-lens scanning exposure apparatus, a configuration is known in which a plurality of illuminance sensors are arranged on a plate stage in order to detect the illuminance on the plate. The plurality of illuminance sensors are configured to measure the illuminance of an overlap exposure region among a plurality of exposure regions formed by, for example, a multi lens.

  For example, as described in Patent Document 1, a plurality of illuminance sensors detect the illuminance of a plurality of overlap exposure areas, and after shifting the overlap exposure areas by one pitch, the plurality of illuminance sensors again detect one pit. A technique for detecting the illuminance of the overlapped exposure region at a shifted position is known. This technique enables illuminance measurement in a short time.

JP 2005-11990 A

  However, in the method described in Patent Document 1, the above measurement cannot be performed while the plate is exchanged on the plate stage. For this reason, it takes time for the exchange of the plate and the measurement, respectively, and there is a problem in terms of throughput.

  In view of the circumstances as described above, an aspect of the present invention is to provide an exposure method, an exposure apparatus, and a device manufacturing method capable of improving throughput.

  According to the first aspect of the present invention, the step of irradiating the pattern disposed on the first surface with exposure light, the step of irradiating the substrate disposed on the second surface with the exposure light via the pattern, and Detecting the first illuminance of the exposure light on the upstream side of the optical path of the exposure light from the second surface, detecting the second illuminance of the exposure light on the second surface, and the first There is provided an exposure method including a step of associating illuminance with the second illuminance and a step of adjusting the second illuminance based on the first illuminance.

  According to the second aspect of the present invention, an exposure apparatus that irradiates the mask disposed on the first stage with exposure light and irradiates the substrate disposed on the second stage with the exposure light via the mask pattern. A first detection device that detects a first illuminance of the exposure light upstream of the second stage with respect to the optical path of the exposure light, and the exposure on the second stage provided in the second stage. A second detection device that detects a second illuminance of light, and a control device that associates the first illuminance with the second illuminance and outputs adjustment information of the second illuminance based on the first illuminance. An exposure apparatus is provided.

  According to a third aspect of the present invention, exposing the substrate using the exposure method described above, developing the exposed substrate to form an exposure pattern layer corresponding to the pattern, And processing the substrate through the exposed pattern layer.

  According to the aspects of the present invention, it is possible to provide an exposure method, an exposure apparatus, and a device manufacturing method capable of improving throughput.

1 is a schematic block diagram showing an example of an exposure apparatus according to a first embodiment of the present invention. 1 is a perspective view showing an example of an exposure apparatus according to the present embodiment. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. The flowchart which shows the process of illumination intensity calibration. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. FIG. 2 is a plan view showing an example of an exposure apparatus according to the present embodiment. The flowchart for demonstrating an example of the manufacturing process of a microdevice.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto. In the following description, an XYZ orthogonal coordinate system is set, and the positional relationship of each part will be described with reference to this XYZ orthogonal coordinate system. A predetermined direction in the horizontal plane is defined as an X-axis direction, a direction orthogonal to the X-axis direction in the horizontal plane is defined as a Y-axis direction, and a direction orthogonal to each of the X-axis direction and the Y-axis direction (that is, a vertical direction) is defined as a Z-axis direction. In addition, the rotation (inclination) directions around the X axis, the Y axis, and the Z axis are the θX, θY, and θZ directions, respectively.

  FIG. 1 is a schematic block diagram showing an example of an exposure apparatus EX according to this embodiment, and FIG. 2 is a perspective view. 1 and 2, the exposure apparatus EX includes an illumination system IS that illuminates the mask M with exposure light EL, a mask stage MST that can move while holding the mask M, and a drive system 3 that moves the mask stage MST. A projection system PS that projects an image of the pattern of the mask M illuminated by the exposure light EL onto the plate P, a plate stage PST that can move while holding the plate P, and a drive system 4 that moves the plate stage PST, And a control device 5 that controls the overall operation of the exposure apparatus EX. Further, the exposure apparatus EX includes an interferometer system 6 (6A, 6B) that measures position information of the mask stage MST and the plate stage PST, and an alignment system 9 that detects alignment marks on the plate P.

  The mask M includes a reticle on which a device pattern projected onto the plate P is formed. The plate P includes, for example, a base material such as a glass plate and a photosensitive film (coated photosensitizer) formed on the base material. In the present embodiment, the plate P includes a large glass plate, and the size of one side of the plate P is, for example, 500 mm or more. In the present embodiment, a rectangular glass plate having a side of about 3000 mm is used as the base material of the plate P.

  The exposure apparatus EX of the present embodiment is a so-called multilens scan exposure apparatus. That is, the projection system PS has a plurality of projection optical systems PL (PL1 to PL7), and projects a pattern image of the mask M onto the plate P while moving the mask M and the plate P in synchronization with a predetermined scanning direction. It has become.

  The illumination system IS includes a lamp house 10, a light guide unit 13, and an illumination module IL. The lamp house 10 includes a light source 11a, a dichroic mirror 11b, a fiber part 11c, an illuminance sensor 11d, and a filter part 12. For example, a mercury lamp is used as the light source 11a. From the mercury lamp, for example, bright lines such as g-line, h-line, and i-line are emitted as exposure light EL. The dichroic mirror 11b reflects the exposure light from the light source 11a to the filter unit 12 and transmits the exposure light to the fiber unit 11c. The fiber part 11c is disposed at a position optically conjugate with the light source 11a. The illuminance sensor 11d is optically connected to the fiber part 11c.

  The filter unit 12 is provided with various filters such as a wavelength selection filter 12a and a neutral density filter 12b. The light guide unit 13 guides the exposure light EL from the lamp house 10 to the illumination module IL. For example, an optical fiber or the like is used.

  A plurality of, for example, seven illumination modules IL are provided so as to correspond to the plurality of projection optical systems PL1 to PL7. Each of the illumination modules IL1 to IL7 has an optical system such as an illumination wedge 14, a fly-eye lens 15, and a condenser lens 16, respectively. The number of illumination modules IL and projection optical systems PL is not limited to seven. For example, the illumination system IS may have 11 illumination modules, and the projection system PS may have 11 projection optical systems.

  The illumination system IS can irradiate the predetermined illumination areas IR1 to IR7 on the mask M with the exposure light EL. The illumination areas IR1 to IR7 are included in the irradiation areas of the exposure light EL emitted from the illumination modules IL1 to IL7. In the present embodiment, the illumination system IS illuminates each of the seven different illumination areas IR1 to IR7 with the exposure light EL. The illumination system IS illuminates portions of the mask M arranged in the illumination areas IR1 to IR7 with the exposure light EL having a uniform illuminance distribution.

  Mask stage MST is movable with respect to illumination regions IR1 to IR7 while holding mask M. The mask stage MST includes a mask holding unit 25 that can hold the mask M. The mask holding unit 25 includes a chuck mechanism that can vacuum-suck the mask M, and holds the mask M in a releasable manner. In the present embodiment, the mask holding unit 25 holds the mask M so that the lower surface (pattern formation surface) of the mask M and the XY plane are substantially parallel. The drive system 3 includes, for example, a linear motor, and can move the mask stage MST on the XY plane. In the present embodiment, the mask stage MST is movable in three directions of the X axis, the Y axis, and the θZ direction with the mask M held by the mask holder 25 by the operation of the drive system 3. An X blind 21 is provided on the mask stage MST. The X blind 21 is provided so as to be movable in the X direction, and shields at least a part of the exposure light EL irradiated to the mask M. One X blind 21 is provided on each of the + X side and the −X side of the mask stage MST.

  FIG. 3 is a plan view showing a configuration on the mask stage MST. In FIG. 3, a part of the configuration on the mask stage MST is omitted. Further, the portion indicated by the alternate long and short dash line in FIG. 3 is the holding position of the mask M on the mask stage MST.

  As shown in FIG. 3, the illuminance sensor 40 is provided on the mask stage MST. The illuminance sensor 40 detects the illuminance of the exposure light EL applied to the mask M of the mask stage MST. The illuminance sensor 40 can detect the illuminance of exposure light at the same Z coordinate as the Z coordinate of the mask M.

  For example, six illuminance sensors 40 are provided along the + X side edge of the mask stage MST. The six illuminance sensors 41 to 46 are arranged, for example, at the same pitch as the pitch of each joint portion of the illumination areas IR1 to IR7. FIG. 3 shows a state where the Y coordinate of each of the illuminance sensors 41 to 46 and the Y coordinate of the joint portion of the illumination areas IR1 to IR7 are exactly the same. The detection results by the illuminance sensors 41 to 46 are transmitted to the control device 5 and stored in the control device 5.

  1 and 2, the projection system PS has a plurality of projection optical systems PL (PL1 to PL7). The plurality of projection optical systems PL1 to PL7 can irradiate the predetermined projection areas PR1 to PR7 (see FIG. 3) with the exposure light EL. The projection areas PR1 to PR7 correspond to the irradiation areas of the exposure light EL emitted from the projection optical systems PL1 to PL7. In the present embodiment, the projection system PS projects a pattern image on each of seven different projection regions PR1 to PR7. The projection system PS projects an image of the pattern of the mask M at a predetermined projection magnification onto the portion of the plate P arranged in the projection regions PR1 to PR7. Each projection optical system PL1 to PL7 has a field stop 31 and a Y blind 32.

  FIG. 4 is a plan view showing a configuration on the plate stage PST. In FIG. 4, a part of the configuration on the plate stage PST is omitted. Further, in FIG. 4, the portions indicated by the alternate long and short dash line are the holding position of the plate P on the plate stage PST and the setting positions of the exposure areas PA1 to PA6 on the plate P.

  As shown in FIG. 4, the plate stage PST is movable with respect to the projection regions PR1 to PR7 while holding the plate P. The plate stage PST has a plate holder 36 that can hold the plate P. The plate holding unit 36 includes a chuck mechanism that can vacuum-suck the plate P, and holds the plate P in a releasable manner.

  In the present embodiment, the plate holding unit 36 holds the plate P so that the surface (exposure surface) of the plate P and the XY plane are substantially parallel. The plate holding unit 36 holds the plate P so that the surface of the plate P and the surface of the mask M are optically conjugate. The drive system 4 includes, for example, a linear motor, and can move the plate stage PST on the guide surface BPG of the base plate BP. In the present embodiment, the plate stage PST operates on the guide surface BPG with the plate P held by the plate holding portion 36 by the operation of the drive system 4, and the X axis, Y axis, Z axis, θX, θY, and It can move in six directions of θZ direction.

  An illuminance sensor 50 is provided on the plate stage PST. The illuminance sensor 50 detects the illuminance of the exposure light EL irradiated to the plate stage PST. For example, six illuminance sensors 50 are provided along the + X side edge of the plate stage PST. The six illuminance sensors 51 to 56 are arranged at the same pitch as the pitch of each joint portion of the projection regions PR1 to PR7, for example. FIG. 4 shows a state in which the Y coordinates of the illuminance sensors 51 to 56 and the Y coordinates of the joint portions of the projection regions PR1 to PR7 are exactly the same. The detection results by the illuminance sensors 51 to 56 are transmitted to the control device 5 and stored in the control device 5.

  The projection areas PR1 to PR7 correspond to the illumination areas IR1 to IR7, respectively. The projection areas PR1 to PR7 are formed at optically conjugate positions with the corresponding illumination areas IR1 to IR7, respectively.

  Next, an example of the operation of the exposure apparatus EX when the plate P is exposed will be described. At least a part of each operation of the exposure apparatus EX is executed based on predetermined control information (exposure control information) relating to exposure. The exposure control information includes a control command group that defines the operation of the exposure apparatus EX, and is also called an exposure recipe. In the following description, the control information related to exposure is appropriately referred to as an exposure recipe.

  The exposure recipe is stored in the control device 5 in advance. At least the operating conditions of the exposure apparatus EX at the time of exposure of the plate P (during the irradiation operation of the exposure light EL on the mask M and the plate P) are determined in advance by the exposure recipe. The control device 5 controls the operation of the exposure apparatus EX based on the exposure recipe. The exposure recipe includes the movement conditions of the mask stage MST and the plate stage PST when the plate P is exposed. When the plate P is exposed, the control device 5 moves the mask stage MST and the plate stage PST based on the exposure recipe.

  The control device 5 carries the mask M into the mask stage MST based on the exposure recipe. After the mask M is held on the mask stage MST, a setup process including an alignment process of the mask M, various measurement processes, and a calibration process is performed. After the mask M setup process, the control device 5 carries the plate P into the plate stage PST. After the plate P is held on the plate stage PST, a setup process including an alignment process, various measurement processes, and a calibration process for the plate P is performed.

  An exposure processing procedure by the exposure apparatus EX will be specifically described. After the setup process of the mask M and the plate P, the control device 5 sends the exposure light EL to the pattern area MA on the lower surface of the mask M while synchronously moving the mask M and the plate P in the scanning direction based on the exposure recipe. Irradiate (actual exposure step: step 101). The exposure light EL is incident on the projection optical systems PL1 to PL7 through the pattern area MA. The exposure light incident on the projection optical systems PL1 to PL7 is irradiated onto the exposure areas PA1 to PA6 (see FIG. 3) on the surface of the plate P via the projection optical systems PL1 to PL7, and the exposure areas PA1 to PA6 are exposed. Is done.

  In the exposure process for the plurality of exposure areas PA1 to PA6 provided on the plate P, the exposure areas PA1 to PA6 are moved in the scanning direction along the surface (XY plane) of the plate P with respect to the projection areas PR1 to PR7. The pattern area MA of the mask M is executed while moving in the scanning direction along the lower surface (XY plane) of the mask M with respect to the illumination areas IR1 to IR7. In the present embodiment, the scanning direction (synchronous movement direction) of the plate P is the X-axis direction, and the scanning direction (synchronous movement direction) of the mask M is also the X-axis direction.

  For example, when exposing the exposure area PA1 of the plate P, the control device 5 moves the exposure area PA1 of the plate P in the X-axis direction with respect to the projection areas PR1 to PR7, and moves the plate P in the X-axis direction. In synchronization with the illumination areas IR1 to IR7, the pattern area MA of the mask M is moved in the X-axis direction, and the illumination areas IR1 to IR7 are irradiated with the exposure light EL, so that the exposure light EL from the mask M is irradiated. The projection areas PR1 to PR7 are irradiated through the projection optical system PL. Thereby, the exposure area PA1 of the plate P is exposed by the exposure light EL irradiated to the projection areas PR1 to PR7, and the pattern image of the pattern area MA of the mask M is transferred to the exposure area PA1 of the plate P.

  For example, in order to expose the next exposure area (for example, the exposure area PA2) after the exposure of the exposure area PA1 is completed, the control device 5 places the projection areas PR1 to PR7 at the exposure start position of the next exposure area PA2. As described above, the plate stage PST is controlled to move the plate P in the predetermined direction in the XY plane with respect to the projection regions PR1 to PR7. Further, the control device 5 controls the mask stage MST to move the mask M with respect to the illumination areas IR1 to IR7 so that the illumination areas IR1 to IR7 are arranged at the exposure start positions of the pattern area MA. Then, after the projection areas PR1 to PR7 are arranged at the exposure start position of the exposure area PA2, and the illumination areas IR1 to IR7 are arranged at the exposure start position of the pattern area MA, the control device 5 performs the exposure of the exposure area PA2. Start.

  The controller 5 irradiates the plate P with the exposure light EL while synchronously moving the mask M held by the mask stage MST and the plate P held by the plate stage PST in the X-axis direction, and exposes the next exposure area. In order to achieve this, the mask M is provided with a plurality of exposure areas PA1 to PA6 provided on the plate P while repeating the stepping movement of the plate P in a predetermined direction (for example, the X-axis direction) in the XY plane. Sequential exposure is performed via the pattern and projection optical system PL. When the exposure of all the exposure areas PA1 to PA6 is completed, the exposure process for the plate P is terminated. The control device 5 causes such exposure processing to be performed while appropriately replacing the mask M, for example.

Next, the exposure light illuminance calibration operation will be described with reference to FIGS. FIG. 5 is a flowchart showing a process of illuminance calibration operation.
For example, when the mask M is out of the field of the projection optical system PL or when the mask M is replaced, the control device 5 performs exposure light illuminance calibration. 6-8 is a figure which shows the positional relationship between the illumination intensity sensors 51-56 and projection area | region PR1-PR7 in sensitivity calibration and illumination intensity calibration.
End portions (joints) in the Y direction of the projection regions PR1 to PR7 formed on the plate P are overlapped when the projection regions PR1 to PR7 are moved in the X direction (overlap). Exposure area). Specifically, the projection region PR1 has an overlap exposure region at the end on the −Y side. Each of the projection areas PR2 to PR6 has an overlap exposure area at the + Y side end and the −Y side end. The projection region PR7 has an overlap exposure region at the end on the + Y side. The sensitivity calibration of the illuminance sensors 51 to 56 and the illuminance calibration operation of the exposure light are performed based on the illuminance of the overlap exposure region of the exposure light.

  In the exposure light illuminance calibration operation, the control device 5 first performs sensitivity calibration of the illuminance sensors 51 to 56. The control device 5 uses the illuminance sensors 51 to 56 to detect the illuminance at a plurality of locations in the overlap exposure areas of the projection areas PR2, PR4, and PR6. In this embodiment, for example, the illuminance at six illuminance detection points (m1 to m6) is detected.

  As shown in FIG. 6, the control device 5 moves the plate stage PST so that the illuminance sensors 51 to 56 and the illuminance detection points m1 to m6 of the projection regions PR2, PR4, and PR6 overlap each other (step S10). After moving the plate stage PST, the control device 5 simultaneously detects the illuminance at the illuminance detection points m1 to m6 using the illuminance sensors 51 to 56 (step S11).

  After detecting the illuminance, the control device 5 moves the plate stage PST by one pitch in the direction orthogonal to the scanning direction (X direction) (Y direction) (step S12). By this operation, as shown in FIG. 7, the illuminance sensor 52 located at the illuminance detection point m2 is moved to the position of the illuminance detection point m1, and the illuminance sensor 53 located at the illuminance detection point m3 is moved to the illuminance detection point. The illuminance sensor 54 located at the illuminance detection point m4 moves to the illuminance detection point m3, and the illuminance sensor 55 located at the illuminance detection point m5 moves to the illuminance detection point m4. The illuminance sensor 56 that has been moved and located at the illuminance detection point m6 moves to the position of the illuminance detection point m5. In this embodiment, in step S12, the stage is moved by one pitch in the direction orthogonal to the scanning direction. However, the plate stage may be moved by more than one pitch in the direction orthogonal to the scanning direction.

  After moving the plate stage PST by one pitch, the control device 5 detects the illuminance at the illuminance detection points m1 to m5 using the illuminance sensors 52 to 56 (step S13). In step S <b> 13, the illuminance sensor 51 is located away from the illuminance detection points m <b> 1 to m <b> 6, so the control device 5 prevents the illuminance sensor 51 from performing illuminance detection.

  The control device 5 performs sensitivity calibration between the illuminance sensors 51 to 56 based on the illuminance of the illuminance detection points m1 to m6 measured by the illuminance sensors 51 to 56 in Step S11 and Step S13 (Step S11 and Step S13). S14). When the sensitivity calibration is performed, the control device 5 uses the illuminance sensor 51 as a reference illuminance sensor when sensitivity calibration is performed on the illuminance sensor 51 in advance. Based on the illuminance at the illuminance detection point m1 measured by the illuminance sensor 51 and the illuminance detection point m1 measured by the illuminance sensor 52, the control device 5 has the same sensitivity as the sensitivity of the illuminance sensor 51. Let's perform sensitivity calibration.

  After the sensitivity calibration of the illuminance sensor 52 is performed, the control device 5 detects the sensitivity of the illuminance sensor 52 subjected to the sensitivity calibration, the illuminance at the illuminance detection point m2 detected by the illuminance sensor 52, and the illuminance sensor 53. The sensitivity calibration of the illuminance sensor 53 is performed based on the illuminance at the illuminance detection point m2. Similarly, sensitivity calibration of the illuminance sensors 54 to 56 is performed.

  In the present embodiment, six illuminance sensors are provided, but it is sufficient that two or more illuminance sensors are provided. In this embodiment, the illuminance sensor 51 is used as the reference illuminance sensor. However, sensitivity calibration is performed on any one of the illuminance sensors 52 to 56, and the illuminance sensor subjected to sensitivity calibration is used as the reference illuminance sensor. It may be used as

  After performing the sensitivity calibration of the illuminance sensors 51 to 56 in step S14, the control device 5 moves the plate stage PST in the Y direction so that the illuminance sensor 56 overlaps the position of the illuminance detection point m1 (step S15). With this operation, only the illuminance sensor 56 is disposed at a position overlapping the illuminance detection point m1, and the illuminance sensors 51 to 55 do not overlap any illuminance detection point. After moving the plate stage PST, the control device 5 uses the illuminance sensor 56 to detect the illuminance at the illuminance detection point m1 (step S16).

After detecting the illuminance in step S16, the control device 5 calculates an accumulated error between the illuminance sensors 51 to 56 based on the detection result (step S17). For example, in the sensitivity calibration in steps S11 to S14, when the same illuminance detection point is detected using the adjacent illuminance sensor, if the detection result shifts due to illuminance ripple or the like, the sensitivity is corrected in step S14. The deviation becomes a cumulative error in all the illuminance sensors 51 to 56 and is included in the calibration result. In this case, the accumulated error in the illuminance sensors 51 to 56 increases in a geometric progression from the illuminance sensor 51 to the illuminance sensor 56. Specifically, the detection result including an error in each illuminance sensor is Sn (however, the illuminance sensor 51 is n = 1, the illuminance sensor 52 is n = 2,..., The illuminance sensor 56 is n = 6), and the cumulative amount. Is α, and a detection value S ₀ that does not include a cumulative error in the illuminance sensor 51 is
S _n = S _n−1 · α
= S ₀ · α ⁿ
It becomes.

In the present embodiment, the control device 5 performs step S15 and step S16 so that the accumulated error is not reflected in the illuminance calibration. Specifically, the control device 5 compares the detection result of step S16 with the detection result of the illuminance sensor 51 in the sensitivity calibration, and calculates an error value δ in the illuminance sensor 56. The control device 5 calculates the value of the cumulative amount α based on the calculated value. In the present embodiment, since six illuminance sensors 56 are provided, α = δ ^1/6 . After calculating the cumulative value α in this way and calculating the accumulated error included in each of the illuminance sensors 51 to 56, the control device 5 determines the sensitivity of each of the illuminance sensors 51 to 56 based on the calculation result. Calibration is performed again (step S18).

  After the sensitivity calibration of the illuminance sensors 51 to 56 is performed again in step S18, the control device 5 performs the illuminance calibration of the exposure light passing through the illumination modules IL1 to IL7 and the projection optical systems PL1 to PL7. In the present embodiment, illuminance calibration is performed separately for a set of projection areas PR1, PR3, PR5, and PR7 and a set of projection areas PR2, PR4, and PR6.

  First, as shown in FIG. 8, the control device 5 sets the plate stage so that the positions of the illuminance detection points m7 to m12 in the projection areas PR1, PR3, PR5, and PR7 coincide with the positions of the illuminance sensors 51 to 56. The PST is moved (step S19). After moving the plate stage PST, the control device 5 detects the illuminance at the illuminance detection points m7 to m12 using the illuminance sensors 51 to 56 (step S20). After detecting the illuminance, the control device 5 determines the illuminance of the exposure light based on the result of sensitivity calibration of the illuminance sensors 51 to 56 in steps S11 to S18 and the detection result of the illuminance detection points m7 to m12 detected in step S19. Is adjusted (step S21).

  When adjusting the illuminance of light, for example, the control device 5 moves the neutral density filter 12b in a direction orthogonal to the optical axis to adjust the illuminance of the light passing through the neutral density filter 12b. In the case of individually adjusting the illuminance of exposure light passing through the illumination modules IL1 to IL7 and the projection optical systems PL1 to PL7, the control device 5 is provided in the illumination modules IL1 to IL7 that are the adjustment targets of the illuminance. Adjust the illuminance using the variable illuminance mechanism.

  After performing the illuminance calibration for the illuminance detection points m7 to m12, the control device 5 detects the illuminance at the illuminance detection points m7 to m12 using the illuminance sensors 51 to 56 (step S22). After the re-detection, the control device 5 determines whether or not the illuminance adjustment of the exposure light is accurately performed in step S17 based on the illuminance detection values of the illuminance detection points m7 to m12 acquired again (step S23). ).

  When it is determined that the illuminance adjustment of the exposure light is not accurately performed (NO in step S23), the control device 5 repeatedly performs the adjustment operation in step S21 and the determination in step S22. If it is determined that the illuminance adjustment of the exposure light has been accurately performed (YES in step S23), the control device 5 moves the plate stage PST in the scanning direction (step S24), and the projection regions PR2, PR4, PR6. Shift to illuminance calibration for the set. In this manner, the control device 5 causes illuminance calibration for the set of the projection areas PR1, PR3, PR5, and PR7.

  After performing the illuminance calibration for the set of the projection areas PR1, PR3, PR5, and PR7, the control device 5 causes the illuminance calibration for the set of the projection areas PR2, PR4, and PR6 to be performed in the same manner. The control device 5 causes the illuminance sensors 51 to 56 to detect the illuminance at the illuminance detection points m1 to m6 again (step S25), and adjusts the illuminance of the exposure light using the detection result (step S26). It is determined whether or not the illuminance adjustment has been accurately performed (step S27). When it is determined that the illuminance adjustment of the exposure light is not accurately performed, the illuminance of the exposure light is adjusted again to determine whether the readjustment has been performed correctly. If it is determined that the illuminance adjustment of the exposure light has been accurately performed, the illuminance calibration process is terminated.

  After the illuminance calibration described above, the control device 5 causes the illumination areas IR1 to IR7 to be detected using the illuminance sensors 41 to 46 on the mask stage MST side. The controller 5 also detects the illuminance in the illumination areas IR1 to IR7 separately for the illumination areas IR1, IR3, IR5, and IR7 and the illumination areas IR2, IR4, and IR6. 9 and 10 are diagrams showing a positional relationship between the illumination regions IR1 to IR7 and the illuminance sensors 41 to 46. FIG.

  First, as shown in FIG. 9, the controller 5 sets the mask stage MST so that the illuminance sensors 41 to 46 overlap the illuminance detection positions n1 to n6 that are the overlapping illumination areas of the illumination areas IR1, IR3, IR5, and IR7. Is moved (step S28). After the movement of the mask stage MST, the control device 5 detects the illuminance at each of the illuminance detection positions n1 to n6 using the illuminance sensors 41 to 46 (step S29). After detecting the illuminance, the control device 5 stores the detection result (step S30).

  After storing the detection results, the control device 5 causes the illuminance sensors 41 to 46 to overlap the illuminance detection positions n7 to n12 that are the overlapping illumination areas of the illumination areas IR2, IR4, and IR6, as shown in FIG. Then, the mask stage MST is moved (step S31). After moving the mask stage MST, the control device 5 uses the illuminance sensors 41 to 46 to detect the illuminance at the illuminance detection positions n7 to n12 (step S32). After detecting the illuminance, the control device 5 stores the detection result (step S33).

  The control device 5 can obtain the illuminance data of the illumination regions IR1 to IR7 immediately after the illuminance calibration by the operations of Step S28 to Step S33. The control device 5 can perform illuminance calibration using the illuminance sensors 41 to 46 of the mask stage MST by using the illuminance data of the illumination regions IR1 to IR7. Specifically, the control device 5 can perform illuminance calibration using the illuminance sensors 41 to 46 on the mask stage MST side, for example, while the plate P is exchanged in the plate stage PST.

  As described above, according to the present embodiment, the illuminance of the exposure light in the projection areas PR1 to PR7 on the plate stage PST is detected, and the illuminance of the illumination areas IR1 to IR7 on the mask stage MST is associated with the detection result. Therefore, by detecting the illuminance of the illumination areas IR1 to IR7 on the mask stage MST and adjusting the illuminance of the illumination areas IR1 to IR7 using the detection result, the illuminance of the projection areas PR1 to PR7 is substantially increased. Calibration can be performed. In this case, for example, the exposure light illuminance calibration can be performed using the time during which the plate P is replaced in the plate stage PST, so that the processing time can be shortened as compared with the case where each is performed separately. Can do. Thereby, the throughput can be improved.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the detection results of the illuminance sensors 51 to 56 are associated with the detection results of the illuminance sensors 41 to 46. However, the present invention is not limited to this. For example, the illuminance sensor 11d in the lamp house 10 The illuminance calibration may be performed using the detection result of the illuminance sensor 11d in association with the detection result. In this case, since the illuminance calibration can be performed even while the mask M is exchanged in the mask stage MST, it is possible to further improve the throughput.

  Moreover, in the said embodiment, when adjusting the illumination intensity of exposure light, it demonstrated and demonstrated the example which adjusts using the neutral density filter 12b, but it is not restricted to this, For example, the electric power of the light source 11a is adjusted. By doing so, the illuminance of the exposure light may be adjusted. Further, the illuminance may be adjusted using the X blind 21 or the Y blind 32 in the projection optical system PL.

  Further, in the above-described embodiment, the example in which the illuminance sensors 50 for detecting the illuminances of the projection regions PR1 to PR7 on the plate stage PST are six (illuminance sensors 51 to 56) has been described, but the present invention is not limited thereto. There is nothing, and it is sufficient if the illuminance sensor 50 is one or more.

  In addition, as the plate P of the above-described embodiment, not only a glass substrate for a display device but also a semiconductor wafer for manufacturing a semiconductor device, a ceramic wafer for a thin film magnetic head, or an original mask or reticle used in an exposure apparatus ( Synthetic quartz, silicon wafer) or the like is applied.

  As the exposure apparatus EX, a step-and-scan type scanning exposure apparatus (scanning stepper) that scans and exposes the plate P with the exposure light EL through the pattern of the mask M by moving the mask M and the plate P synchronously. In addition, the pattern of the mask M is collectively exposed while the mask M and the plate P are stationary, and is applied to a step-and-repeat projection exposure apparatus (stepper) that sequentially moves the plate P stepwise. Can do.

  The present invention also relates to a twin-stage type exposure having a plurality of substrate stages as disclosed in US Pat. No. 6,341,007, US Pat. No. 6,208,407, US Pat. No. 6,262,796, and the like. It can also be applied to devices.

  Further, the present invention relates to a substrate stage for holding a substrate as disclosed in US Pat. No. 6,897,963, European Patent Application No. 1713113, etc., and a reference mark without holding the substrate. The present invention can also be applied to an exposure apparatus that includes a formed reference member and / or a measurement stage on which various photoelectric sensors are mounted. An exposure apparatus including a plurality of substrate stages and measurement stages can be employed.

  The type of exposure apparatus EX is not limited to an exposure apparatus for manufacturing a liquid crystal display element or a display, but an exposure apparatus for manufacturing a semiconductor element that exposes a semiconductor element pattern on a plate P, a thin film magnetic head, and an image sensor (CCD). In addition, the present invention can be widely applied to an exposure apparatus for manufacturing a micromachine, MEMS, DNA chip, reticle, mask, or the like.

  In each of the above-described embodiments, the position information of each stage is measured using an interferometer system including a laser interferometer. However, the present invention is not limited to this. For example, a scale (diffraction grating) provided in each stage You may use the encoder system which detects this.

  In the above-described embodiment, a light-transmitting mask in which a predetermined light-shielding pattern (or phase pattern / dimming pattern) is formed on a light-transmitting substrate is used. As disclosed in US Pat. No. 6,778,257, a variable shaped mask (also called an electronic mask, an active mask, or an image generator) that forms a transmission pattern, a reflection pattern, or a light emission pattern based on electronic data of a pattern to be exposed. ) May be used. Further, a pattern forming apparatus including a self-luminous image display element may be provided instead of the variable molding mask including the non-luminous image display element.

  The exposure apparatus EX of the above-described embodiment is manufactured by assembling various subsystems including the respective constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Is done. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy. The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus. The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  As shown in FIG. 6, a microdevice such as a semiconductor device includes a step 201 for designing a function / performance of the microdevice, a step 202 for manufacturing a mask (reticle) based on the design step, and a substrate as a base material of the device. Manufacturing step 203, including substrate processing (exposure processing) including exposing the substrate with exposure light using a mask pattern and developing the exposed substrate (photosensitive agent) according to the above-described embodiment The substrate is manufactured through a substrate processing step 204, a device assembly step (including processing processes such as a dicing process, a bonding process, and a packaging process) 205, an inspection step 206, and the like. In step 204, the photosensitive agent is developed to form an exposure pattern layer (developed photosensitive agent layer) corresponding to the mask pattern, and the substrate is processed through the exposure pattern layer. It is.

  EX ... Exposure apparatus M ... Mask EL ... Exposure light IS ... Illumination system MST ... Mask stage PST ... Plate stage PL ... Projection optical system IL ... Illumination module m1-m12, n1-n12 ... Illuminance detection point IR1-IR7 ... Illumination area IR PR1 to PR7 Projection area PR 10 Lamp house 11d Illuminance sensor 40, 41 to 46 Illuminance sensor 50, 51 to 56 Illuminance sensor

Claims (17)

Irradiating exposure light to the pattern disposed on the first surface;
Irradiating the substrate disposed on the second surface with the exposure light via the pattern;
Detecting a first illuminance of the exposure light upstream of the optical path of the exposure light from the second surface;
Detecting a second illuminance of the exposure light on the second surface;
Associating the first illuminance with the second illuminance;
Adjusting the second illuminance based on the first illuminance;
An exposure method comprising:   The exposure method according to claim 1, wherein the first illuminance is an illuminance of the exposure light on a conjugate plane optically conjugate with the second surface. Irradiating the substrate with the exposure light includes projecting an image of the pattern onto the second surface;
The exposure method according to claim 2, wherein the conjugate plane is the first plane. The step of detecting the second illuminance detects the second illuminance at a plurality of positions on the second surface,
4. The exposure method according to claim 2, wherein the step of detecting the first illuminance detects the first illuminance at a plurality of conjugate positions conjugate with the plurality of positions. 5.   5. The exposure method according to claim 4, wherein in the step of detecting the second illuminance, the second illuminance at the plurality of positions is detected by different sensors. The step of detecting the second illuminance includes
Detecting the second illuminance at a first position of the plurality of positions by a first sensor of the plurality of sensors;
Detecting the second illuminance at a second position of the plurality of positions by a second sensor of the plurality of sensors;
Detecting the second illuminance at the second position by the first sensor;
Calibrating the first sensor and the second sensor based on detection results of the first sensor at the first position and the second position;
The exposure method according to claim 5 comprising: The plurality of positions are arranged along a predetermined direction,
The first position and the second position are one end position and the other end position of the plurality of positions, respectively.
The step of detecting the second illuminance includes, based on the detection results of the first sensor at the first position and the second position, between the first position and the second position among the plurality of positions. The exposure method according to claim 6, further comprising: calibrating a plurality of the sensors corresponding to the respective positions arranged on the surface.   The exposure method according to claim 1, wherein the calibration is performed based on a difference between detection values of the first sensor at the first position and the second position.   The exposure method according to claim 1, wherein at least one of the step of detecting the first illuminance and the step of adjusting the second illuminance is performed during a period in which the substrate replacement process is performed. .   The step of adjusting the second illuminance changes at least one of a light emission amount of the light source of the exposure light and a transmittance of the exposure light at a predetermined position on the upstream side of the optical path of the exposure light from the first surface. The exposure method according to any one of claims 1 to 9. An exposure apparatus that irradiates a mask disposed on a first stage with exposure light and irradiates the substrate disposed on a second stage with the exposure light via a pattern of the mask,
A first detector that detects a first illuminance of the exposure light upstream of the optical path of the exposure light from the second stage;
A second detector provided on the second stage for detecting a second illuminance of the exposure light in the second stage;
A controller that associates the first illuminance with the second illuminance and outputs adjustment information of the second illuminance based on the first illuminance;
An exposure apparatus comprising:   The exposure apparatus according to claim 11, wherein the first detection device is provided on the first stage.   The exposure apparatus according to claim 11, further comprising a projection optical system that projects an image of the pattern of the mask disposed on the first stage onto the substrate disposed on the second stage. The second detection device detects the second illuminance at a plurality of positions in an imaging plane of the projection optical system;
The exposure apparatus according to claim 13, wherein the first detection device detects the first illuminance at a plurality of conjugate positions conjugate with the plurality of positions.   The exposure apparatus according to claim 14, wherein the second detection apparatus includes a plurality of sensors that respectively detect the second illuminance at the plurality of positions.   An adjustment device that changes at least one of a light emission amount of the light source of the exposure light and a transmittance of the exposure light at a predetermined position upstream of the optical path of the exposure light from the first stage based on the adjustment information. An exposure apparatus according to any one of claims 11 to 15. Exposing the substrate using the exposure method according to any one of claims 1 to 10,
Developing the exposed substrate to form an exposed pattern layer corresponding to the pattern;
Processing the substrate through the exposure pattern layer.

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