JP4760019B2 - Exposure apparatus and device manufacturing method - Google Patents

Description

The present invention relates to an exposure apparatus for manufacturing a flat panel display element such as a liquid crystal display element in a lithography process, and a device manufacturing method using the exposure apparatus.

  Currently, in the manufacture of semiconductor integrated circuits, a photolithography technique using visible light or ultraviolet light is used to transfer a very fine pattern formed on a mask onto a photosensitive substrate. In a manufacturing process using this photolithography technique, an electronic device such as a liquid crystal display device or a semiconductor device is manufactured by a so-called photolithography technique in which a pattern formed on a mask is transferred onto a photosensitive substrate. An exposure apparatus used in this photolithography process has a mask stage on which a mask having a pattern is placed and moved two-dimensionally and a substrate stage on which a photosensitive substrate is placed and moved two-dimensionally, and is formed on the mask. The exposed pattern is projected and exposed to the photosensitive substrate through the projection optical system while sequentially moving the mask stage and the substrate stage. The exposure apparatus includes a batch type exposure apparatus that simultaneously transfers the entire mask pattern onto the photosensitive substrate, and a scanning type exposure that continuously transfers the mask pattern onto the photosensitive substrate while synchronously scanning the mask stage and the substrate stage. Two types of devices are mainly known. Among these, when manufacturing a liquid crystal display device, a scanning type exposure apparatus is mainly used because of a demand for a large display area (see, for example, Patent Document 1).

  In this scanning exposure apparatus, the focus sensor detects the position (focus position) in the optical axis direction of the projection optical system on the mask pattern formation surface and the exposed surface of the photosensitive substrate in real time, and controls the focus position. Yes.

JP 2004-177468 A

  In the exposure apparatus described above, the focus position is detected in real time by the focus sensor. However, since the focus sensor is not positioned on the photosensitive substrate at the start of exposure (scanning) of the top substrate of the lot, the focus is focused. The position cannot be detected in real time. Therefore, before starting the exposure, in order to detect the focus position at the start of exposure (scanning), the focus sensor is moved onto the photosensitive substrate to detect the focus position, the detection result is stored, and the stored detection result is stored. Since the exposure (scanning) was started based on this, the throughput was reduced. In addition, since the conditions for detecting the focus position of the photosensitive substrate at the start of the above-described exposure (scanning) (for example, scan acceleration, speed, substrate stage attitude, etc.) are different from the actual exposure conditions, accurate exposure is possible. It was difficult to detect the focus position of the substrate.

An object of the present invention is to provide an exposure apparatus capable of accurately detecting the focus position of a photosensitive substrate without causing a decrease in throughput, and a device manufacturing method using the exposure apparatus.

The exposure apparatus according to the present invention is an exposure apparatus that scans and exposes a pattern on a photosensitive substrate by moving a stage device that supports the photosensitive substrate in the scanning direction, and is arranged in two rows along the direction intersecting the scanning direction. A projection optical unit that projects the pattern onto the photosensitive substrate by the plurality of projection optical systems, and is disposed on one side in the scanning direction with respect to the projection area of the projection optical unit. A mark detection system for detecting a plurality of marks provided on the photosensitive substrate, and at least between the projection optical unit and the mark detection system with respect to the scanning direction, and an optical axis direction of the projection optical unit A position detection system for detecting the position of the photosensitive substrate in the first position, and the stage device at a first position where the mark detection system can detect the plurality of marks. A first control for causing the mark detection system to detect the plurality of marks and for the position detection system to detect the position of the photosensitive substrate; from the first position to the one side in the scanning direction; The stage device is moved so that the photosensitive substrate is disposed on the one side in the scanning direction with respect to the projection area of the projection optical unit, and the stage device is disposed at a second position where the scanning exposure is started. A second control for driving the stage device based on a detection result of the position detection system at the first position, and correcting a position of the photosensitive substrate in the optical axis direction for the scanning exposure. And a control device for performing the fourth control for starting the scanning exposure by moving the stage device from the second position to the other side in the scanning direction from the second position. Characterized in that it obtain.

  According to the exposure apparatus of the present invention, the relative position for correcting the relative position between the surface inclination and the image surface of the mask pattern based on the measurement results at a plurality of different positions in the substrate plane detected by the plurality of position detecting means. Since it is equipped with a correction means, it is not necessary to perform a separate sequence for detecting the relative position between the surface inclination and the image surface of the mask pattern before the exposure is started, unlike the conventional exposure apparatus, and the exposure processing capability Can be improved.

According to another aspect of the present invention, there is provided a method of manufacturing a device having a circuit pattern, wherein the circuit pattern is exposed by an exposure process of scanning exposure of the circuit pattern onto a photosensitive substrate using the exposure apparatus of the present invention. And a developing step of developing the photosensitive substrate on which the pattern is exposed .

According to the device manufacturing method of the present invention, since exposure is performed using an exposure apparatus in which the focus position is accurately adjusted, the device can be manufactured at a high throughput and a good device can be obtained. Can do.

  According to the exposure apparatus of the present invention, the relative position for correcting the relative position between the surface inclination and the image surface of the mask pattern based on the measurement results at a plurality of different positions in the substrate plane detected by the plurality of position detecting means. Since it is equipped with a correction means, it is not necessary to perform a separate sequence for detecting the relative position between the surface inclination and the image surface of the mask pattern before the exposure is started, unlike the conventional exposure apparatus, and the exposure processing capability Can be improved.

Further, according to the device manufacturing method of the present invention, since exposure is performed using an exposure apparatus in which the focus position is accurately adjusted, the device can be manufactured with high throughput, and a good device can be manufactured. Obtainable.

  An exposure apparatus according to the first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram of the exposure apparatus according to the first embodiment, and FIG. 2 is a schematic perspective view of the exposure apparatus shown in FIG.

  1 and 2, an exposure apparatus EX includes an illumination optical system IL including a plurality of illumination system modules 10a to 10k that illuminate a mask M with exposure light, a mask stage MST that supports the mask M, and an illumination system module. A plurality of projection optical systems PL1 for projecting an image of the pattern of the mask M arranged corresponding to each of 10a to 10k and illuminated with exposure light onto a photosensitive substrate (photosensitive substrate) P having an outer diameter larger than 500 mm. ~ PL11, substrate stage PST for supporting the photosensitive substrate P, mask side laser interferometers 39a and 39b for detecting the position of the mask stage MST using laser light, and detecting the position of the substrate stage PST using laser light Substrate side laser interferometers 43a and 43b. In this embodiment, there are eleven illumination system modules 10a to 10k, and only those corresponding to the illumination system module 10a are shown in FIG. 1 for convenience, but each of the illumination system modules 10a to 10k is the same. It has the composition of. The photosensitive substrate P is obtained by applying a resist (photosensitive agent) to a glass plate.

  The exposure apparatus EX transfers the pattern of the mask M to the photosensitive substrate P via the projection optical systems PL1 to PL11 while synchronously moving the mask M supported by the mask stage MST and the photosensitive substrate P supported by the substrate stage PST. This is a scanning exposure apparatus that performs projection exposure. In the following description, the optical axis direction of the projection optical systems PL1 to PL11 is the Z-axis direction, the synchronous movement direction (scanning direction) of the mask M and the photosensitive substrate P in the direction perpendicular to the Z-axis direction is the X-axis direction, and Z A direction (non-scanning direction) perpendicular to the axial direction and the X-axis direction is defined as a Y-axis direction.

  As shown in FIG. 1, the illumination optical system IL is necessary for exposure among the exposure light source 6, the elliptical mirror 6a that condenses the light beam emitted from the light source 6, and the light beam collected by the elliptical mirror 6a. A dichroic mirror 7 that reflects a light beam having a wavelength and transmits a light beam having another wavelength, a wavelength selection filter 8 that passes only a wavelength necessary for exposure among light beams reflected by the dichroic mirror 7, and a wavelength selection filter 8. The light guide 9 is branched into a plurality of light beams (11 in the present embodiment) and incident on each of the illumination system modules 10 a to 10 k via the reflection mirror 11. A mercury lamp is used as the light source 6 for exposure in the present embodiment, and the g-line (436 nm), h-line (405 nm), i-line (365 nm), which are wavelengths necessary for exposure, are applied by the wavelength selection filter 8 as exposure light. ) Etc. are used.

  The illumination system module 10 a includes an illumination shutter 12, a relay lens 13, an optical integrator 14 that adjusts a light beam that has passed through the relay lens 13 to a light beam having a substantially uniform illuminance distribution, and converts the light into exposure light. And a condenser lens 15 that condenses exposure light and illuminates the mask M with uniform illuminance. In this embodiment, illumination system modules 10b to 10k having the same configuration as the illumination system module 10a are arranged with a certain interval in the X-axis direction and the Y-axis direction.

  The illumination shutter 12 is disposed on the downstream side of the light path of the light guide 9 so as to be movable back and forth with respect to the light path of the light beam, and shields / releases the light beam. The illumination shutter 12 is provided with a shutter drive unit 12D that moves the illumination shutter 12 forward and backward with respect to the optical path of the light flux, and the drive is controlled by the control unit CONT. The light beam that has passed through the illumination shutter 12 reaches the optical integrator 14 via the relay lens 13. A secondary light source is formed on the exit surface side of the optical integrator 14, and exposure light from the optical integrator 14 irradiates the mask M supported by the mask stage MST through the condenser lens 15 with uniform illuminance. Then, the exposure light emitted from each of the illumination system modules 10a to 10k illuminates each of the different illumination areas on the mask M.

  The mask stage MST that supports the mask M is movably provided, and has a long stroke in the X-axis direction and a stroke of a predetermined distance in the Y-axis direction orthogonal to the scanning direction in order to perform one-dimensional scanning exposure. Have. As shown in FIG. 1, the mask stage MST has a mask stage drive unit MSTD that drives the mask stage MST in the X-axis direction and the Y-axis direction. The mask stage driving unit MSTD is controlled by the control device CONT.

  As shown in FIG. 2, the mask side laser interferometer includes an X laser interferometer 39a that detects the position of the mask stage MST in the X-axis direction and a Y laser interferometer 39b that detects the position of the mask stage MST in the Y-axis direction. And. An X moving mirror 38a extending in the Y-axis direction is provided at the + X side edge of the mask stage MST. On the other hand, a Y moving mirror 38b extending in the X-axis direction is provided at the + Y side edge of the mask stage MST so as to be orthogonal to the X moving mirror 38a. Further, an X laser interferometer 39a is disposed facing the X moving mirror 38a, and a Y laser interferometer 39b is disposed facing the Y moving mirror 38b.

  The X laser interferometer 39a irradiates the X moving mirror 38a with laser light. The light (reflected light) generated by the X moving mirror 38a by the laser light irradiation is received by a detector inside the X laser interferometer 39a. Based on the reflected light from the X moving mirror 38a, the X laser interferometer 39a detects the position of the X moving mirror 38a, that is, the position of the mask stage MST in the X axis direction based on the position of the internal reference mirror. The position of the mask M can be monitored with the inspection value of the laser interferometer by measuring each position of the mask M with respect to the mask stage MST.

  The Y laser interferometer 39b irradiates the Y moving mirror 38b with laser light. The light (reflected light) generated by the Y moving mirror 38b by the laser light irradiation is received by a detector inside the Y laser interferometer 39b. The Y laser interferometer 39b is based on the reflected light from the Y moving mirror 38b, with the position of the internal reference mirror as a reference, that is, the position of the Y moving mirror 38b, that is, the position of the mask stage MST (and thus the mask M) in the Y axis direction. Is detected.

  The detection results of the laser interferometers 39a and 39b are output to the control device CONT. The control device CONT drives the mask stage MST via the mask stage drive unit MSTD based on the detection results of the laser interferometers 39a and 39b, and controls the position of the mask M.

  The exposure light transmitted through the mask M enters each of the projection optical systems PL1 to PL11. Each of the projection optical systems PL1 to PL11 projects and exposes an image of a pattern existing in the illumination area of the mask M onto the photosensitive substrate P, and is arranged corresponding to each of the illumination system modules 10a to 10k. The projection optical systems PL1, PL3, PL5, PL7, PL9, PL11 (first projection optical unit) and the projection optical systems PL2, PL4, PL6, PL8, PL10 (second projection optical unit) are arranged in a staggered pattern in two rows. Has been. That is, each of the projection optical systems PL1 to PL11 arranged in a staggered manner is arranged by displacing adjacent projection optical systems (for example, projection optical systems PL1 and PL2, PL2 and PL3) by a predetermined amount in the X-axis direction. Yes. The exposure light transmitted through each of the projection optical systems PL1 to PL11 forms an image of a pattern corresponding to the illumination area of the mask M on different projection areas on the photosensitive substrate P supported by the substrate stage PST. The pattern of the mask M in the illumination area has a predetermined imaging characteristic and is transferred onto the photosensitive substrate P coated with a resist.

  The substrate stage PST that supports the photosensitive substrate P is movably provided, and has a long stroke in the X-axis direction for performing one-dimensional scanning exposure and a Y-axis for stepping in a direction orthogonal to the scanning direction. With a long stroke in the direction. The substrate stage PST has a substrate stage drive unit PSTD that drives the substrate stage PST in the X-axis direction and the Y-axis direction, and further in the Z-axis direction. The substrate stage drive unit PSTD is controlled by the control device CONT.

  As shown in FIG. 2, the substrate side laser interferometer includes an X laser interferometer 43a that detects the position of the substrate stage PST in the X-axis direction and a Y laser interferometer 43b that detects the position of the substrate stage PST in the Y-axis direction. And. An X moving mirror 42a extending in the Y-axis direction is provided at the + X side edge of the substrate stage PST. On the other hand, a Y moving mirror 42b extending in the X-axis direction is provided at the −Y side edge of the substrate stage PST so as to be orthogonal to the X moving mirror 42a. An X laser interferometer 43a is disposed opposite to the X movable mirror 42a, and a Y laser interferometer 43b is disposed opposite to the Y movable mirror 42b.

  The X laser interferometer 43a irradiates the X moving mirror 42a with laser light. The light (reflected light) generated by the X moving mirror 42a by the laser light irradiation is received by the detector inside the X laser interferometer 43a. Based on the reflected light from the X moving mirror 42a, the X laser interferometer 43a uses the position of the internal reference mirror as a reference, that is, the position of the X moving mirror 42a, that is, the X direction of the substrate stage PST (and hence the photosensitive substrate P). Detect position.

  The Y laser interferometer 43b irradiates the Y moving mirror 42b with laser light. The light (reflected light) generated by the Y moving mirror 42b by the laser light irradiation is received by the detector inside the Y laser interferometer 43b. The Y laser interferometer 43b detects the position of the Y moving mirror 42b, that is, the position of the substrate stage PST in the Y-axis direction based on the position of the internal reference mirror based on the reflected light from the Y moving mirror 42b. The position of the photosensitive substrate P can be monitored with the inspection value of the laser interferometer by measuring each position of the photosensitive substrate P with respect to the substrate stage PST. The detection results of the laser interferometers 43a and 43b are output to the control device CONT.

  Each of the mask stage MST and the substrate stage PST can be independently moved by the mask stage driving unit MSTD and the substrate stage driving unit PSTD under the control of the control device CONT. In this embodiment, the mask stage MST that supports the mask M and the substrate stage PST that supports the photosensitive substrate P move in the X-axis direction at an arbitrary scanning speed (synchronous movement speed) with respect to the projection optical systems PL1 to PL11. Move to sync.

  Further, on the −X side of the projection optical systems PL1, PL3, PL5, PL7, PL9, and PL11 (first projection optical unit), positions of the pattern forming surface of the mask M and the exposed surface of the photosensitive substrate P in the Z-axis direction. An autofocus detection system (position detection means, first detection means) 50 for detecting (focus position) is provided. As shown in FIG. 3, the autofocus detection system 50 includes a plurality (three in this embodiment) of photosensitive substrate position detection systems 50a, 50b, 50c arranged in a direction (Y direction) orthogonal to the scanning direction. , And a plurality (two in this embodiment) of mask position detection systems arranged in the Y direction (not shown). Note that P1 shown in FIG. 3 is a region (exposure region) where the light flux through the projection optical system PL1 is exposed on the photosensitive substrate P, and each of P2 to P11 is a light flux through each of the projection optical systems PL2 to PL11. Is an area (exposure area) where the photosensitive substrate P is exposed. The focus position at three position detection points of the exposed surface of the photosensitive substrate P detected by the three photosensitive substrate position detection systems 50a to 50c, and 2 of the pattern formation surface of the mask M detected by the two mask position detection systems. The focus positions at the two position detection points are output to the control device CONT.

  Further, on the + X side of the projection optical systems PL2, PL4, PL6, PL8, and PL10 (second projection optical unit), the positions (focus positions) of the pattern forming surface of the mask M and the exposed surface of the photosensitive substrate P in the Z-axis direction. An autofocus detection system (position detection means, second detection means) 52 is provided. That is, the autofocus detection systems 50 and 52 are in a positional relationship in which the first projection optical unit and the second projection optical unit are sandwiched in the scanning direction (X direction). As shown in FIG. 3, the autofocus detection system 52 is arranged in a plurality of (two in this embodiment) photosensitive substrate position detection systems 52a and 52b arranged in the Y direction, and in the Y direction (not shown). A plurality (two in this embodiment) of mask position detection systems are provided. Further, the focus position at two position detection points of the exposed surface of the photosensitive substrate P detected by the two photosensitive substrate position detection systems 52a and 52b, and the pattern formation surface of the mask M detected by the two mask position detection systems. The focus positions at the two position detection points are output to the control device CONT.

  The control device (surface inclination calculating means) CONT calculates the surface inclination of the photosensitive substrate P based on the focus position on the exposed surface of the photosensitive substrate P detected by the autofocus detection systems 50 and 52. Further, the surface inclination of the mask M is calculated based on the focus position on the pattern formation surface of the mask M detected by the autofocus detection systems 50 and 52, and the projection optical systems PL1 to PL1 are calculated based on the calculated surface inclination of the mask M. The image plane of the pattern of the mask M projected onto the photosensitive substrate P via PL11 is calculated. The relative position between the calculated surface inclination of the photosensitive substrate P and the image surface of the pattern of the mask M projected onto the photosensitive substrate P via the projection optical systems PL1 to PL11 is used as the substrate stage drive unit PSTD (or mask stage drive). The substrate stage PST (or the mask stage MST) is moved by driving the part MSTD) to correct.

  An alignment detection system 54 that detects a plurality of alignment marks provided on the photosensitive substrate P is provided on the −X side of the autofocus detection system 50. As shown in FIG. 3, the alignment detection system 54 includes a plurality (six in this embodiment) of alignment mark detection systems 54a to 54f arranged in the Y direction. Alignment mark positions on the photosensitive substrate P provided corresponding to 54a to 54f are detected. The alignment mark positions detected by the six alignment mark detection systems 54a to 54f are output to the control device CONT. The control device CONT uses the six alignment mark positions detected by the alignment detection system 54 and the baseline amount calculated and stored in advance based on the relative positional relationship between the mask M and the alignment detection system 54. A correction amount for aligning M and the photosensitive substrate P is calculated, and the position of the substrate stage PST (or mask stage MST) is calculated based on the calculated correction amount, and the substrate stage driving unit PSTD (or mask stage driving unit). MSTD) is driven to correct.

  Next, a first focus position correction method in the exposure apparatus according to the first embodiment will be described. FIG. 4 is a flowchart for explaining a focus position correction process performed before the substrate stage PST starts scanning in the exposure apparatus according to this embodiment.

  First, the control device CONT replaces the photosensitive substrate P and places the photosensitive substrate P on the substrate stage PST (step S10). Next, as shown in FIG. 5, the control device CONT places the substrate stage PST at a position where the alignment detection system 54 can detect the positions of the first alignment marks m1 to m6 provided on the photosensitive substrate P. The drive unit PSTD is driven and moved (step S11).

  Next, the control device CONT performs alignment (alignment) between the mask M and the photosensitive substrate P by the alignment detection system 54, and simultaneously with the alignment, the focus position on the exposed surface of the photosensitive substrate P by the autofocus detection systems 50 and 52. Is detected (step S12). That is, the three photosensitive substrate position detection systems 50a to 50c of the autofocus detection system 50 and the two photosensitive substrate position detection systems 52a and 52b of the autofocus detection system 52 are five detection points f1 to f1 of the exposed surface of the photosensitive substrate P. The focus position at f5 is detected, and the detected focus positions of the five detection points f1 to f5 are output to the control device CONT.

Next, the control device CONT determines the surface inclination of the exposed surface of the photosensitive substrate P (hereinafter referred to as “first”) based on the focus positions at the five detection points f1 to f5 of the exposed surface of the photosensitive substrate P detected in step S12. Is calculated (step S13). That is, based on the focus positions of the five detection points f1 to f5 detected in step S12, the tilt in the X direction (θ _X ) and the tilt in the Y direction with respect to the optical axis of the projection optical systems PL1 to PL11 of the photosensitive substrate P ( θ _Y ) and the height (Z) in the Z direction are calculated. Next, the control device CONT stores the first surface inclination calculated in step S13 in a storage unit (not shown) (step S14).

  Next, as shown in FIG. 6, the control apparatus CONT places the substrate stage PST at a position where the alignment detection system 54 can detect the positions of the second alignment marks m7 to m12 provided on the photosensitive substrate P. The drive unit PSTD is driven and moved, and alignment (alignment) between the mask M and the photosensitive substrate P is performed by the alignment detection system 54 (step S15).

  Next, as shown in FIG. 7, the control apparatus CONT moves the substrate stage PST to the exposure (scan) start position by driving the substrate stage drive unit PSTD, and the first surface tilt stored in step S15. Based on this, the focus position of the exposed surface of the photosensitive substrate P is corrected (step S16). Specifically, the control device CONT outputs a control signal to the substrate stage drive unit PSTD, and the substrate stage drive unit PSTD drives the substrate stage PST based on the control signal from the control device CONT, thereby photosensitive substrate. The focus position of the exposed surface of P is corrected.

  Next, a second focus position correction method in the exposure apparatus according to the first embodiment will be described. FIG. 8 is a flowchart for explaining a focus position correction process performed after the substrate stage PST starts scanning in the exposure apparatus according to this embodiment.

  First, the control device CONT outputs a control signal to the substrate stage drive unit PSTD, drives the substrate stage drive unit PSTD, and moves the substrate stage PST, thereby scanning for exposure from the position shown in FIG. Start (step S20). Here, when scanning is started from the position shown in FIG. 7, as shown in FIG. 9, before actual exposure is started, that is, the light flux through the projection optical systems PL1, PL3, PL5, PL7, PL9, and PL11. Before reaching the photosensitive substrate P, scanning is performed until the end of the substrate is detected, and after detecting the end of the substrate (step S21, Yes), the photosensitive substrate position detection systems 50a and 50b of the autofocus detection system 50 are detected by the photosensitive substrate. Reach on P. The edge of the substrate can be detected by monitoring a signal in which the output of the autofocus detection system 50 changes rapidly.

  Next, the control device CONT detects the focus position on the exposed surface of the photosensitive substrate P by the photosensitive substrate position detection systems 50a and 50b of the autofocus detection system 50 that has reached the photosensitive substrate P before actual exposure is started. Is performed (step S22). That is, of the three photosensitive substrate position detection systems 50a to 50c of the autofocus detection system 50, the two photosensitive substrate position detection systems 50a and 50b located on the photosensitive substrate P are two detection points on the exposed surface of the photosensitive substrate P. The focus positions at f6 and f7 are detected, and the detected focus positions at the two detection points f6 and f7 are output to the control device CONT.

  Next, the control unit CONT stores the two detection points f6 and f7 on the exposed surface of the photosensitive substrate P detected in step S22 in the storage unit (not shown) as the first focus position (step S23). Next, the control device CONT is moved from the first focus position by a predetermined distance (step S24).

  Next, as shown in FIG. 10, the control device CONT detects two detection points different from the two detection points f6 and f7 detected in step S22 by the photosensitive substrate position detection systems 50a and 50b of the autofocus detection system 50. The focus positions (second focus positions) of the points f8 and f9 are detected (step S25). That is, of the three photosensitive substrate position detection systems 50a to 50c of the autofocus detection system 50, the two photosensitive substrate position detection systems 50a and 50b located on the photosensitive substrate P are two detection points on the exposed surface of the photosensitive substrate P. The second focus positions at f8 and f9 are detected, and the detected second focus positions at the two detection points f8 and f9 are output to the control device CONT.

Next, the control device CONT is based on the first focus positions of the two detection points f6 and f7 detected in step S22 and the second focus positions of the two detection points f8 and f9 detected in step S25. Then, the surface inclination of the exposed surface of the photosensitive substrate P (hereinafter referred to as the second surface inclination) is calculated (step S26). That is, since the two detection points f6 and f7 and the two detection points f8 and f9 are detection points that are not arranged in a straight line, the optical axis of the projection optical system of the photosensitive substrate P is based on the four detection points f6 to f9. The inclination in the X direction (θ _X ), the inclination in the Y direction (θ _Y ), and the height in the Z direction (Z) can be calculated. Next, the control device CONT stores the second surface inclination calculated in step S26 in a storage unit (not shown) (step S27).

  Next, the control device CONT corrects the focus position of the exposed surface of the photosensitive substrate P based on the second surface inclination stored in step S27 (step S28). Specifically, the control device CONT outputs a control signal to the substrate stage drive unit PSTD, and the substrate stage drive unit PSTD drives the substrate stage PST based on the control signal from the control device CONT, thereby photosensitive substrate. The focus position of the exposed surface of P is corrected. The operations in steps S25 to S28 are repeated until the autofocus detection system 52 is positioned on the photosensitive substrate P.

  Next, as shown in FIG. 11, when the autofocus detection system 52 arrives on the photosensitive substrate P, the control device CONT covers the photosensitive substrate P covered by the photosensitive substrate position detection systems 50a and 50b of the autofocus detection system 50. Detection of the focus positions of the two detection points f10 and f11 on the exposure surface and the focus positions of the two detection points f12 and f13 on the exposed surface of the photosensitive substrate P by the photosensitive substrate position detection systems 52a and 52b of the autofocus detection system 52. Is performed (step S29). That is, of the three photosensitive substrate position detection systems 50 a to 50 c of the autofocus detection system 50, two photosensitive substrate position detection systems 50 a and 50 b positioned on the photosensitive substrate P and two photosensitive substrate positions of the autofocus detection system 52. The detection systems 52a and 52b respectively detect the focus positions at the detection points f10 to f11 on the exposed surface of the photosensitive substrate P, and the detected focus positions of the four detection points f10 to f11 are output to the control device CONT. Is done.

Next, the control device CONT calculates the surface inclination of the exposed surface of the photosensitive substrate P (hereinafter referred to as the third surface inclination) based on the focus positions of the four detection points f10 to f11 detected in step S29. (Step S30). That is, since the two detection points f10 and f11 and the two detection points f12 and f13 are not aligned in a straight line, the projection optical systems PL1 to PL11 on the photosensitive substrate P are based on the four detection points f10 to f13. The tilt in the X direction (θ _X ), the tilt in the Y direction (θ _Y ), and the height in the Z direction (Z) can be calculated. Next, the control device CONT stores the third surface inclination calculated in step S30 in a storage unit (not shown) (step S31).

  Next, the control device CONT corrects the focus position of the exposed surface of the photosensitive substrate P based on the third surface inclination stored in step S31 (step S32). Specifically, the control device CONT outputs a control signal to the substrate stage drive unit PSTD, and the substrate stage drive unit PSTD drives the substrate stage PST based on the control signal from the control device CONT, thereby photosensitive substrate. The focus position of the exposed surface of P is corrected. The operations in steps S22 to S32 are repeated while only the autofocus detection system 50 is positioned on the photosensitive substrate P.

  The above-described correction of the focus position of the photosensitive substrate P is performed when the first photosensitive substrate is installed and when the second and third photosensitive substrates are installed. When the fourth and subsequent photosensitive substrates are installed, four sheets are obtained based on the first surface inclination, the second surface inclination, and the third surface inclination calculated when the previous three photosensitive substrates are installed. The focus position of the photosensitive substrate after the first is corrected.

  Further, in the detection of the focus position of the photosensitive substrate P by the above-described autofocus detection system 50, the photosensitive substrate position detection system 50c of the autofocus detection system 50 is not positioned on the photosensitive substrate P. Although the focus position of the photosensitive substrate P is not detected by 50c, when the photosensitive substrate position detection system 50c is positioned on the photosensitive substrate P, the focus position of the photosensitive substrate P is detected by the photosensitive substrate position detection system 50c. And the surface inclination is calculated based on the detected focus position.

  In FIG. 8, after detecting the first focus positions at the two detection points f6 and f7 on the exposed surface of the photosensitive substrate P detected at step S22, the second focus positions at the detection points f8 and f9 are determined. Although the embodiment in which the focus control is not performed until the detection is performed has been described, the first surface tilt information that cannot be detected only by the first focus position based on the first surface tilt stored in step S15 illustrated in FIG. The surface inclination of the photosensitive substrate P may be calculated using the surface inclination information. That is, the height direction of the photosensitive substrate P may be calculated using the first focus position, and the surface inclination of the photosensitive substrate P may be calculated using the first surface inclination information. By doing in this way, it is possible to start the position control of the photosensitive substrate P at an early stage per exposure, and it is possible to easily perform the control.

  According to the exposure apparatus of the first embodiment, the alignment of the photosensitive substrate P detected by the photosensitive substrate position detection systems 50a to 50c, 52a and 52b included in the autofocus detection systems 50 and 52 at the same time as alignment is performed. The focus position of the exposure surface can be detected, the first surface inclination can be calculated based on the detection result, and the focus position of the photosensitive substrate P can be corrected based on the calculated first surface inclination. Further, after the scan is started and before the exposure is started, the focus positions of the four detection points on the exposed surface of the photosensitive substrate P detected by the photosensitive substrate position detection systems 50a and 50b included in the autofocus detection system 50 are different. , The second surface inclination is calculated based on the detection result, and the focus position of the photosensitive substrate P can be corrected based on the calculated second surface inclination. Further, when the photosensitive substrate position detection systems 52a and 52b included in the autofocus detection system 52 are positioned on the photosensitive substrate P, the focus positions of the two detection points of the photosensitive substrate P are detected by the photosensitive substrate position detection systems 52a and 52b. Detection is performed to detect the focus positions of four different detection points detected by the photosensitive substrate position detection systems 50a, 50b, 52a, and 52b, and the third surface inclination is calculated instead of the second surface inclination based on the detection result. Then, the focus position of the photosensitive substrate P can be corrected based on the calculated third surface inclination.

  Therefore, it is not necessary to detect and correct the surface inclination of the exposed surface of the photosensitive substrate P before starting the exposure as in the conventional exposure apparatus, and the exposure processing capability can be improved.

  Next, with reference to the drawings, an exposure apparatus according to a second embodiment of the present invention will be described. FIG. 12 is a view showing the schematic arrangement of an exposure apparatus according to the second embodiment. The exposure apparatus shown in FIG. 12 exposes a mask stage MST2 that supports a mask M2 on which a pattern is formed, a substrate stage PST2 that supports a photosensitive substrate (photosensitive substrate) P2, and a mask M2 that is supported by the mask stage MST2. An illumination optical system IL2 that illuminates with light EL, a projection optical system PL that projects an image of the pattern of the mask M2 illuminated with exposure light EL onto the photosensitive substrate P2 supported by the substrate stage PST2, and a projection optical system PL A column 100 supported via the surface plate 1 and a control device CONT2 that performs overall control of operations related to exposure processing are provided. The column 100 is installed on a base plate 110 placed horizontally on the floor surface. In the present embodiment, the projection optical system PL has a plurality (seven) of catadioptric projection optical modules, and the illumination optical system IL2 also has a plurality (7) corresponding to the number and arrangement of the projection optical modules. A) illumination optical module. The photosensitive substrate P2 is a glass substrate coated with a photosensitive agent (photoresist).

  This exposure apparatus is a scanning exposure apparatus that performs scanning exposure by synchronously moving the mask M2 and the photosensitive substrate P2 with respect to the projection optical system PL, and constitutes a so-called multi-lens scanning exposure apparatus. Further, this exposure apparatus is provided with an auto focus detection system 500, 520 and an alignment detection system 540 between the projection optical system PL and the photosensitive substrate P2 and at a position sandwiching an exposure region formed by the projection optical system PL. It has been. In the following description, the synchronous movement direction of the mask M2 and the photosensitive substrate P2 is the X-axis direction (scanning direction), the direction orthogonal to the X-axis direction in the horizontal plane is the Y-axis direction (non-scanning direction), the X-axis direction, and the Y-axis. The direction orthogonal to the direction is taken as the Z-axis direction. The directions around the X, Y, and Z axes are the θX, θY, and θZ directions.

  The illumination optical system IL2 has a light source, and illuminates the mask M2 with a plurality of slit-shaped illumination areas with exposure light emitted from the light source. A mercury lamp is used as a light source in the present embodiment, and as exposure light, a wavelength selection filter (not shown) is used for exposure to wavelengths required for exposure, such as g-line (436 nm), h-line (405 nm), and i-line (365 nm). ) Etc. are used.

  Mask stage MST2 is provided on column 100, and includes a mask holder 20 that holds mask M2 and a pair of linear motors (not shown) that can move mask holder 20 with a predetermined stroke in the X-axis direction. ing. Although not shown, the mask stage MST2 also has a moving mechanism that moves the mask holder 20 that holds the mask M2 in the Y-axis direction and the θZ direction.

  The substrate stage PST2 is provided on the base plate 110. The substrate stage PST2 is provided on the substrate holder 30 that holds the photosensitive substrate P2, the guide stage 35 that supports the substrate holder 30 so as to be movable while being guided in the Y-axis direction, and the guide stage 35. A linear motor (not shown) that moves in a direction and a pair of linear motors (not shown) that can move the substrate holder 30 together with the guide stage 35 in the X-axis direction with a predetermined stroke on the base plate 110 are provided. The substrate holder 30 holds the photosensitive substrate P2 via a vacuum chuck. Further, the substrate stage PST2 also has a moving mechanism for moving the substrate holder 30 in the Z-axis direction, θX and θY directions.

  The projection optical system PL has a plurality (seven) of arranged projection optical modules PLa, PLc, PLe, PLg and three projection optical modules (not shown). The plurality of projection optical modules PLa, PLc, PLe, PLg, and Three projection optical modules (not shown) are supported on one surface plate 1. As shown in FIG. 12, the projection optical modules PLa, PLc, PLe, and PLg and the surface plate 1 that supports the projection optical module (not shown) are supported by the column 100 via the support portion 2.

  The four projection optical modules PLa, PLc, PLe, and PLg are arranged in the Y direction (direction intersecting the scanning direction) and arranged on the front side in the X direction (scanning direction) (hereinafter, referred to as the first projection optical module). Called unit). Each of the three projection optical modules (not shown) is arranged in the Y direction and is arranged on the rear side in the X direction (hereinafter referred to as a second projection optical unit). The first projection optical unit and the second projection optical unit are arranged so as to face each other in the X direction, and each projection optical module PLa, PLc, PLe, PLg constituting the first projection optical unit and the second projection are arranged. The projection optical modules (not shown) constituting the optical unit are arranged in a staggered manner. That is, the adjacent projection optical modules are arranged by being displaced by a predetermined amount in the Y direction. Each of the projection optical modules constituting the first projection optical unit and the second projection optical unit includes a lens barrel PK (see FIG. 13) and a plurality of optical elements (lenses) arranged inside the lens barrel PK. have.

  FIG. 13 is a diagram showing a schematic configuration of one projection optical module PLf among the three projection optical modules constituting the second projection optical unit. Hereinafter, the projection optical module PLf will be described, but the other projection optical modules have the same configuration as the projection optical module PLf.

  As shown in FIG. 13, the projection optical module PLf projects and exposes a pattern image existing in the illumination area of the mask M2 illuminated with the exposure light EL by the illumination optical module onto the photosensitive substrate P2, and includes two sets of reflections. Refractive optical systems 151 and 152 and a field stop (not shown) are provided. The light beam transmitted through the mask M2 enters the first set of catadioptric optical system 151. The catadioptric optical system 151 forms an intermediate image of the pattern of the mask M2. A field stop (not shown) is disposed at the intermediate image position of the pattern formed by the catadioptric optical system 151. The field stop sets a projection area on the photosensitive substrate P2, and for example, sets the projection area on the photosensitive substrate P2 in a trapezoidal shape. The light beam that has passed through the field stop is incident on the second set of catadioptric optical system 152.

  The catadioptric optical system 152 has the same configuration as the catadioptric optical system 151. The light beam emitted from the catadioptric optical system 152 forms an image of the pattern of the mask M2 on the photosensitive substrate P2 at an erecting equal magnification.

  The exposure apparatus also includes a laser interference system that measures the position of the mask holder 20 (mask stage MST2). An X moving mirror (not shown) extending in the Y axis direction is provided at the −X side edge of the mask holder 20, and a Y moving mirror 71 extending in the X axis direction is provided at the −Y side edge of the mask holder 20. ing. A laser interferometer (not shown) is provided at a position facing the X moving mirror. A laser interferometer 74 is provided at a position facing the Y moving mirror 71. A laser interferometer and a laser interferometer 74 (not shown) are installed on the column 100. A reference mirror and a reference mirror 77 (not shown) are attached to the surface plate 1. A reference mirror (not shown) is provided at a position facing a laser interferometer (not shown), and a reference mirror 77 is provided at a position facing the laser interferometer 74.

  A measurement result of a laser interferometer (not shown) is output to the control device CONT2, and the control device CONT2 controls the position of the mask holder 20 (mask stage MST2) in the X-axis direction based on the measurement result of the laser interferometer. The measurement result of the laser interferometer 74 is output to the control device CONT2, and the control device CONT2 controls the position of the mask holder 20 (mask stage MST2) in the Y-axis direction based on the measurement result of the laser interferometer 74. That is, the control device CONT2 calculates the posture (position in the X axis, Y axis, θX, θY, and θZ directions) of the surface plate 1 that supports each projection optical module based on the measurement result by each laser interferometer. . The control device CONT2 controls the posture of the mask holder 20 via the mask stage driving device MSTD2 based on the posture measurement result of the surface plate 1.

  The exposure apparatus also includes a laser interference system that measures the position of the substrate holder 30 (substrate stage PST2). An X moving mirror (not shown) extending in the Y axis direction is provided at the −X side edge of the substrate holder 30, and a Y moving mirror 81 extending in the X axis direction is provided at the −Y side edge of the substrate holder 30. ing. A laser interferometer (not shown) is provided at a position facing the X moving mirror, and is installed on the base plate 110. Further, a laser interferometer 85 is provided so as to hang from the column 100 at a position facing the Y moving mirror 81.

  A reference mirror (not shown) is provided on the lens barrel PK of the projection optical module at a position facing each of the laser interferometers. A measurement result of a laser interferometer (not shown) is output to the control device CONT2, and the control device CONT2 controls the position of the substrate holder 30 (substrate stage PST2) in the X-axis direction based on the measurement result of each laser interferometer. The measurement result of the laser interferometer 85 is output to the control device CONT2, and the control device CONT2 controls the position of the substrate holder 30 (substrate stage PST2) in the Y-axis direction based on the measurement result of each laser interferometer. That is, the control device CONT2 calculates the posture (position in the X axis, Y axis, θX, θY, and θZ directions) of the surface plate 1 that supports each projection optical module based on the measurement result by each laser interferometer. . The control device CONT2 controls the posture of the substrate holder 30 via the substrate stage driving device PSTD2 based on the posture measurement result of the surface plate 1.

  Also, as shown in FIGS. 12 and 13, on the −X side of the projection area formed on the photosensitive substrate P2 by the light beams passing through the projection optical modules PLa, PLc, PLe, and PLg constituting the first projection optical unit. An autofocus detection system (position detection means, first detection means) 500 for detecting a position (focus position) in the Z-axis direction is provided. As shown in FIG. 12, the autofocus detection system 500 includes a plurality (three in this embodiment) of photosensitive substrate position detection systems 500a, 500b, and 500c arranged in a direction (Y direction) orthogonal to the scanning direction. And a plurality (two in this embodiment) of mask position detection systems arranged in the Y direction (not shown). The focus position at three position detection points of the exposed surface of the photosensitive substrate P2 detected by the three photosensitive substrate position detection systems 500a to 500c, and 2 of the pattern formation surface of the mask M2 detected by the two mask position detection systems. The focus positions at the two position detection points are output to the control device CONT2.

  Further, as shown in FIG. 13, the + X side Z-axis of the projection area formed on the photosensitive substrate P2 by the light beams passing through the projection optical unit PLf constituting the second projection optical unit and each of the two projection optical units (not shown). An auto force detection system (position detection means, second detection means) 520 for detecting a position in the direction (focus position) is provided. As shown in FIG. 13, the autofocus detection system 520 includes a plurality (two in this embodiment) of photosensitive substrate position detection systems 520a arranged in the Y direction and another photosensitive substrate position detection system (not shown). , And a plurality (two in this embodiment) of mask position detection systems arranged in the Y direction (not shown). In addition, the focus position at two position detection points of the exposed surface of the photosensitive substrate P2 detected by the two photosensitive substrate position detection systems, and two pattern forming surfaces of the mask M2 detected by the two mask position detection systems. The focus position at the position detection point is output to the control device CONT2.

  The control device (surface inclination calculating means) CONT2 calculates the surface inclination of the photosensitive substrate P2 based on the focus position on the exposed surface of the photosensitive substrate P2 detected by the autofocus detection systems 500 and 520. Further, the surface inclination of the mask M2 is calculated based on the focus position on the pattern forming surface of the mask M2 detected by the autofocus detection systems 500 and 520, and each projection optical module is determined based on the calculated surface inclination of the mask M2. The image plane of the pattern of the mask M2 projected onto the photosensitive substrate P2 is calculated. Then, the relative position between the calculated surface inclination of the photosensitive substrate P2 and the image surface of the pattern of the mask M2 projected onto the photosensitive substrate P2 via each projection optical module is used as the substrate stage driving device PSTD2 (or mask stage driving device MSTD2). ) Is driven to move the substrate stage PST2 (or mask stage MST2).

  In addition, an alignment detection system 540 that detects a plurality of alignment marks provided on the photosensitive substrate P <b> 2 is provided on the −X side of the autofocus detection system 500. The alignment detection system 540 has a plurality of alignment mark detection systems arranged in the Y direction, and detects the alignment mark position on the photosensitive substrate P2 provided corresponding to each alignment mark detection system. The alignment mark position detected by each alignment mark detection system is output to the control device CONT2. The control device CONT2 determines the mask based on the plurality of alignment mark positions detected by the alignment detection system 540 and the baseline amount calculated and stored in advance based on the relative positional relationship between the mask M2 and the alignment detection system 540. A correction amount for aligning M2 and the photosensitive substrate P2 is calculated, and the position of the substrate stage PST2 (or mask stage MST2) is determined based on the calculated correction amount, and the substrate stage driving device PSTD2 (or mask stage driving device). MSTD2) is driven to correct.

  Next, a first focus position correction method in the exposure apparatus according to the second embodiment will be described. First, the control device CONT2 performs alignment (first alignment) with the photosensitive substrate P2 replaced with the mask M2 by the alignment detection system 540, and at the same time, each photosensitive substrate position detection system included in the autofocus detection systems 500 and 520. The focus position on the exposed surface of the photosensitive substrate P2 is detected. Since the specific detection method is the same as the detection method according to the first embodiment, detailed description thereof is omitted. The focus positions at the five detection points detected by each photosensitive substrate position detection system are output to the control device CONT2.

Next, based on the detected focus positions at the five detection points of the exposed surface of the photosensitive substrate P2, the control device CONT2 tilts the first surface of the exposed surface of the photosensitive substrate P2, that is, the projection optics of the photosensitive substrate P2. The inclination (θ _X ) in the X direction with respect to the optical axis of the system PL, the inclination (θ _Y ) in the _Y direction, and the height (Z) in the Z direction are calculated, and the calculated first surface inclination is stored in a storage unit (not shown). Let Next, after the second alignment between the mask M and the photosensitive substrate P is performed by the alignment detection system 540, the control device CONT2 moves the substrate stage PST2 by driving the substrate stage driving device PSTD2 to the exposure (scan) start position. In addition, the focus position of the exposed surface of the photosensitive substrate P2 is corrected based on the first surface inclination. Since the specific correction method is the same as the correction method according to the first embodiment, detailed description thereof is omitted.

Next, a second focus position correction method in the exposure apparatus according to the second embodiment will be described. First, the control device CONT2 starts scanning for exposure. Then, before the light beam that has passed through the first projection optical unit reaches the photosensitive substrate P2, the focus position on the exposed surface of the photosensitive substrate P2 by the photosensitive substrate position detection system of the autofocus detection system 500 that has reached the photosensitive substrate P2. The focus positions of two or more detection points detected by each photosensitive substrate position detection system are output to the control device CONT2. Next, the control device CONT2 adds the focus position at two or more detection points of the detected surface of the photosensitive substrate P2 to the stored first surface inclination, and the photosensitive substrate P2 having the first surface inclination. The deviation of the inclination (θ _X ) in the X direction with respect to the optical axis of the projection optical system PL and the height (Z) in the Z direction are calculated, and the calculated deviation is stored in the storage unit.

  Next, the control device CONT2 corrects the focus position of the exposed surface of the photosensitive substrate P2 based on the calculated deviation. Since the specific correction method is the same as the correction method according to the first embodiment, detailed description thereof is omitted. Next, the control device CONT2 detects the focus positions of two or more detection points different from the two or more detection points detected by the autofocus detection system 500, and detects the two or more detection points detected. The focus position is output to the control device CONT2.

Next, the control device CONT2 determines the second exposure surface of the photosensitive substrate P2 based on the focus positions of two or more detection points detected earlier and the focus positions of two or more detection points detected later. The surface tilt, that is, the tilt in the X direction (θ _X ), the tilt in the Y direction (θ _Y ), and the height in the Z direction (Z) with respect to the optical axis of the projection optical system PL of the photosensitive substrate P2 are calculated. The two-surface inclination is stored in a storage unit (not shown). Next, the control device CONT2 corrects the focus position of the exposed surface of the photosensitive substrate P2 based on the second surface inclination. Since the specific correction method is the same as the correction method according to the first embodiment, detailed description thereof is omitted. In the operation of calculating the second surface inclination and correcting the focus position of the exposed surface of the photosensitive substrate P2 based on the calculated second surface inclination, the autofocus detection system 520 is positioned on the photosensitive substrate P2. Repeat until.

  Next, when the autofocus detection system 520 reaches the photosensitive substrate P2, the control device CONT2 determines the focus positions of two or more detection points on the exposed surface of the photosensitive substrate P2 by the autofocus detection system 500, and the autofocus. The detection system 520 detects the focus positions of one or more detection points on the exposed surface of the photosensitive substrate P2, and outputs the detected focus positions of the three or more detection points to the control unit CONT2.

Next, based on the focus positions of the detected three or more detection points, the control device CONT2 tilts the third surface of the exposed surface of the photosensitive substrate P2, that is, the optical axis of the projection optical system PL of the photosensitive substrate P2. The inclination in the X direction (θ _X ), the inclination in the Y direction (θ _Y ), and the height in the Z direction (Z) are calculated, and the calculated third surface inclination is stored in a storage unit (not shown). Next, the control device CONT2 corrects the focus position of the exposed surface of the photosensitive substrate P2 based on the third surface inclination. Since the specific correction method is the same as the correction method according to the first embodiment, detailed description thereof is omitted. The operation of calculating the third surface inclination and correcting the focus position of the exposed surface of the photosensitive substrate P2 based on the calculated third surface inclination is performed by the autofocus detection systems 500 and 520 on the photosensitive substrate P2. Repeated while in position.

  The above-described correction of the focus position of the photosensitive substrate P2 is performed when the first photosensitive substrate is installed and when the second and third photosensitive substrates are installed. When the fourth and subsequent photosensitive substrates are installed, four sheets are obtained based on the first surface inclination, the second surface inclination, and the third surface inclination calculated when the previous three photosensitive substrates are installed. The focus position of the photosensitive substrate after the first is corrected.

  According to the projection exposure apparatus of the second embodiment, the focus position of the exposed surface of the photosensitive substrate P2 detected by the photosensitive substrate position detection system included in the autofocus detection systems 500 and 520 at the same time as the alignment is performed. It is possible to detect, calculate the first surface inclination based on the detection result, and correct the focus position of the photosensitive substrate P2 based on the calculated first surface inclination. Further, after the start of scanning and before the start of exposure, the focus positions of three or more detection points with different exposed surfaces of the photosensitive substrate P2 detected by the photosensitive substrate position detection system included in the autofocus detection system 500 are detected. Then, the second surface inclination can be calculated based on the detection result, and the focus position of the photosensitive substrate P2 can be corrected based on the calculated second surface inclination. When the photosensitive substrate position detection system included in the autofocus detection system 520 is positioned on the photosensitive substrate P2, the photosensitive substrate position detection system detects the focus position of one or more detection points on the photosensitive substrate P2, The focus positions of three or more different detection points detected by the respective photosensitive substrate position detection systems of the auto focus detection systems 500 and 520 are detected, and the third surface tilt is substituted for the second surface tilt based on the detection result. The focus position of the photosensitive substrate P2 can be corrected based on the calculated third surface inclination.

  Therefore, it is not necessary to detect and correct the surface inclination of the exposed surface of the photosensitive substrate P2 before starting the exposure as in the conventional exposure apparatus, and the exposure processing capability can be improved.

  In the projection exposure apparatus according to each of the above-described embodiments, the focus position of the photosensitive substrate detected at the first alignment position during exposure (scanning) while the autofocus detection system is not positioned on the photosensitive substrate. Therefore, the conditions for detecting the focus position of the photosensitive substrate (for example, scanning acceleration, speed, substrate stage attitude, etc.) are not the same as the actual exposure conditions. When the autofocus detection system is positioned on the photosensitive substrate, the surface tilt of the photosensitive substrate is corrected based on the focus position detected in real time. It matches the condition. Therefore, a large error may occur in the detection value and the correction value of the focus position before and after the boundary between the position where the focus position of the photosensitive substrate cannot be detected in real time and the position where it can be detected by the autofocus detection system.

  In this case, the substrate stage is simulated and scanned under the same conditions as the actual exposure before and after the boundary between the position where the focus position of the photosensitive substrate cannot be detected in real time and the position where it can be detected by the autofocus detection system (only scanning is performed, In this case, the focus position of the photosensitive substrate may be detected, and the surface inclination of the photosensitive substrate may be corrected based on the detected focus position. For example, when the first to third photosensitive substrates are installed, this autofocus detection system detects the focus position before and after the boundary between the position where the focus position of the photosensitive substrate cannot be detected and the position where it can be detected. Then, the focus position is corrected based on the detected focus position, and when the fourth and subsequent photosensitive substrates are installed, based on the focus position detected when the previous three photosensitive substrates are installed. The focus position of the fourth and subsequent photosensitive substrates is corrected. Further, the focus position of the photosensitive substrate may be corrected when at least one of the exposed photosensitive substrates is installed.

  In this case, since the focus position of the photosensitive substrate can be detected under the same conditions as the actual exposure, a more accurate surface inclination can be calculated. In addition, it is possible to prevent a large error from occurring in the detection value and the correction value of the focus position before and after the boundary between the position where the focus position of the photosensitive substrate cannot be detected in real time and the position where it can be detected by the autofocus detection system.

  In the projection exposure apparatus according to each of the above-described embodiments, the focus position of the photosensitive substrate is corrected when the first to third photosensitive substrates are installed. When at least one photosensitive substrate is installed, the focus position of the photosensitive substrate may be corrected.

  In each of the above-described embodiments, the first surface inclination is calculated by detecting the focus positions of five different detection points on the photosensitive substrate. However, the focus positions of at least three different detection points are detected. By doing so, the first surface inclination may be calculated.

  In each of the embodiments described above, the relative position between the surface inclination and the image plane of the mask pattern projected onto the photosensitive substrate is corrected by inclining the position of the substrate stage. The relative position may be corrected by tilting the position.

  Further, the use of the exposure apparatus is not limited to an exposure apparatus for liquid crystal that exposes a liquid crystal display element pattern on a square glass plate. For example, to manufacture an exposure apparatus for semiconductor manufacturing or a thin film magnetic head The present invention can be widely applied to other exposure apparatuses.

  Increasingly, the size of the photosensitive substrate is increasing, and accordingly, the substrate stage is increased in size and the weight of the substrate stage is increased. However, the exposure apparatus of the present invention is particularly suitable for a photosensitive substrate having an outer shape larger than 500. It is valid.

  The exposure apparatus of the present invention is also effective when exposing a high definition pattern. Further, as an exposure apparatus for manufacturing a wider device pattern, the joint portion is increased by increasing the number of projection optical systems, or the projection area of each projection optical system is enlarged by increasing the angle of view of each projection optical system. Although it is necessary to accurately control the focus position at the joint portion and the peripheral portion of the projection area, the present invention is particularly effective when the focus position of the entire projection area cannot always be detected.

  In the exposure apparatus according to each of the embodiments described above, the reticle (mask) is illuminated by the illumination optical system, and the transfer pattern formed on the mask is exposed to the photosensitive substrate (plate) using the projection optical system ( By the exposure step, a micro device (semiconductor element, imaging element, liquid crystal display element, thin film magnetic head, etc.) can be manufactured. FIG. 14 shows an example of a method for obtaining a semiconductor device as a micro device by forming a predetermined circuit pattern on a plate or the like as a photosensitive substrate using the exposure apparatus according to each of the embodiments described above. This will be described with reference to a flowchart.

  First, in step S301 of FIG. 14, a metal film is deposited on one lot of plates. In the next step S302, a photoresist is applied on the metal film on the one lot of plates. Thereafter, in step S303, using the exposure apparatus according to each of the above-described embodiments, the pattern image on the mask is sequentially exposed and transferred to each shot area on the one lot of plates via the projection optical system. The Thereafter, in step S304, the photoresist on the one lot of plates is developed, and in step S305, etching is performed on the one lot of plates using the resist pattern as a mask to obtain a pattern on the mask. Corresponding circuit patterns are formed in each shot area on each plate.

  Thereafter, a device pattern such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer. According to the above-described microdevice manufacturing method, since exposure is performed using the exposure apparatus according to each of the above-described embodiments, a microdevice having a fine circuit pattern with high throughput can be obtained with high accuracy. In steps S301 to S305, a metal is vapor-deposited on the plate, a resist is applied on the metal film, and exposure, development and etching processes are performed. Prior to these processes, the process is performed on the plate. It is needless to say that after forming a silicon oxide film, a resist may be applied on the silicon oxide film, and steps such as exposure, development, and etching may be performed.

  In the exposure apparatus according to each of the above embodiments, a liquid crystal display element as a microdevice (display device) is formed by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). It can also be obtained. Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG. In FIG. 15, in the pattern formation step S401, there is a so-called photolithography step in which the exposure apparatus according to each of the above embodiments is used to transfer and expose a mask pattern onto a photosensitive substrate (such as a glass substrate coated with a resist). Executed. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate undergoes steps such as a developing step, an etching step, and a resist stripping step, whereby a predetermined pattern is formed on the substrate, and the process proceeds to the next color filter forming step S402.

  Next, in the color filter forming step S402, a large number of groups of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or three of R, G, and B A color filter is formed by arranging a plurality of stripe filter sets in the horizontal scanning line direction. Then, after the color filter formation step S402, a cell assembly step S403 is executed. In the cell assembly step S403, a liquid crystal panel (liquid crystal cell) is assembled using the substrate having the predetermined pattern obtained in the pattern formation step S401, the color filter obtained in the color filter formation step S402, and the like. In the cell assembly step S403, for example, liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern formation step S401 and the color filter obtained in the color filter formation step S402, and a liquid crystal panel (liquid crystal cell ).

  Thereafter, in a module assembly step S404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display element, since exposure is performed using the exposure apparatus according to each of the above-described embodiments, a semiconductor device having a fine circuit pattern with high throughput can be obtained with high accuracy.

It is a figure which shows schematic structure of the projection exposure apparatus concerning 1st Embodiment. It is a perspective view which shows schematic structure of the projection exposure apparatus concerning 1st Embodiment. It is a figure which shows arrangement | positioning of the alignment detection system and autofocus detection system concerning 1st Embodiment. It is a flowchart for demonstrating the correction method of the focus position of the photosensitive substrate before the scan start of the projection exposure apparatus concerning 1st Embodiment. It is a figure for demonstrating the position where the alignment detection system concerning 1st Embodiment performs 1st alignment. It is a figure for demonstrating the position where the alignment detection system concerning 1st Embodiment performs 2nd alignment. It is a figure for demonstrating the first exposure start position of the projection exposure apparatus concerning 1st Embodiment. It is a flowchart for demonstrating the correction method of the focus position of the photosensitive substrate after the scan start of the projection exposure apparatus concerning 1st Embodiment. It is a figure for demonstrating the position where one autofocus detection system concerning 1st Embodiment reached | attained on the photosensitive substrate. It is a figure for demonstrating a position when one autofocus detection system concerning 1st Embodiment detects the focus position of a different point on a photosensitive substrate. It is a figure for demonstrating the position where the other autofocus detection system concerning 1st Embodiment reached | attained on the photosensitive substrate. It is a figure which shows schematic structure of the projection exposure apparatus concerning 2nd Embodiment. It is a figure which shows the positional relationship of the auto-focus detection system and alignment detection system concerning 2nd Embodiment. It is a flowchart which shows the manufacturing method of the semiconductor device as a microdevice concerning embodiment of this invention. It is a flowchart which shows the manufacturing method of the liquid crystal display element as a microdevice concerning embodiment of this invention.

Explanation of symbols

6 ... Light source, 6a ... Elliptic mirror, 10a-10k ... Illumination system module, 20 ... Mask holder, 21 ... Linear motor, 30 ... Substrate holder, 39a, 39b, 74 ... Mask side laser interferometer, 43a, 43b, 85 ... Substrate side laser interferometer, 50, 52, 500, 520 ... autofocus detection system, 54, 540 ... alignment detection system, 151, 152 ... catadioptric optical system, EX ... exposure apparatus, IL, IL2 ... illumination optical system, PL1 to PL11, PL ... projection optical system, PK ... barrel, M, M2 ... mask, MST, MST2 ... mask stage, MSTD ... mask stage drive unit, P, P2 ... photosensitive substrate, PST, PST2 ... substrate stage, PSTD ... Substrate stage drive unit, CONT, CONT2 ... control device.

Claims (10)

In an exposure apparatus that scans and exposes a pattern on the photosensitive substrate by moving a stage device that supports the photosensitive substrate in the scanning direction,
A projection optical unit including a plurality of projection optical systems arranged in two rows along a direction intersecting the scanning direction, and projecting the pattern onto the photosensitive substrate by the plurality of projection optical systems ;
A mark detection system that is arranged on one side in the scanning direction with respect to the projection area of the projection optical unit and detects a plurality of marks provided on the photosensitive substrate;
A position detection system that is disposed at least between the projection optical unit and the mark detection system with respect to the scanning direction and detects the position of the photosensitive substrate in the optical axis direction of the projection optical unit;
The mark detection system moves the stage device to a first position where the plurality of marks can be detected, the mark detection system detects the plurality of marks, and the position detection system sets the position of the photosensitive substrate. First control to be detected, the stage device is moved from the first position to the one side in the scanning direction, and the photosensitive property is moved to the one side in the scanning direction with respect to the projection region of the projection optical unit. The stage device is driven based on the second control for arranging the stage and the stage device at the second position where the scanning exposure is started, and the detection result of the position detection system at the first position. A third control for correcting the position of the photosensitive substrate for the scanning exposure in the optical axis direction, and the second position from the second position to the other side in the scanning direction. A control device that performs a fourth control that initiates the scanning exposure by moving the stage device,
An exposure apparatus comprising:   The control device drives the stage device based on the detection result of the position detection system at the first position to correct the position of the photosensitive substrate in the optical axis direction at the second position. 2. The exposure apparatus according to claim 1, wherein: The position detection system is disposed between the projection optical unit and the mark detection system with respect to the scanning direction, and on the other side in the scanning direction with respect to the projection optical unit. A second position detection system,
The control device causes the first and second position detection systems to detect the position of the photosensitive substrate in the optical axis direction at the first position, and based on the detection results of the first and second position detection systems. The first surface inclination of the photosensitive substrate is calculated, the stage device is driven based on the first surface inclination, and the position of the photosensitive substrate in the optical axis direction for the scanning exposure is determined. 3. An exposure apparatus according to claim 1, wherein control for correction is performed. The plurality of marks include a first mark group and a second mark group that are spaced apart from each other in the scanning direction,
The control device moves the stage device to the first position, causes the mark detection system to detect the first mark group, and causes the position detection system to detect a position of the photosensitive substrate in the optical axis direction. And moving the stage device from the first position to the one side in the scanning direction to dispose the photosensitive substrate on the one side in the scanning direction with respect to the projection area and to the mark detection system The exposure apparatus according to claim 1, wherein after the second mark group is detected, control is performed to place the stage device at the second position.   The control device causes the first and second position detection systems to detect the position of the photosensitive substrate in the optical axis direction at the first position, and among the detection results of the first and second position detection systems. A second surface inclination of the photosensitive substrate is calculated based on at least three points that are not aligned on a straight line, and the stage device is driven based on the second surface inclination, so that the photosensitive for the scanning exposure is performed. 4. An exposure apparatus according to claim 3, wherein control for correcting a position of the conductive substrate in the optical axis direction is performed.   The controller calculates a third surface inclination of the photosensitive substrate based on at least three points that are not aligned on a straight line from the detection results of the first and second position detection systems after the start of exposure, 6. The exposure according to claim 5, wherein the stage device is driven based on a third surface inclination to perform control for correcting the position of the photosensitive substrate in the optical axis direction for the scanning exposure. apparatus.   The said control apparatus performs said 1st and 3rd control with respect to at least 1 sheet | seat of the lot which is a process group of the said photosensitive board | substrate, The any one of Claims 1-6 characterized by the above-mentioned. The exposure apparatus described. The projection optical unit includes a plurality of projection optical systems that are arranged along a non-scanning direction orthogonal to the scanning direction and each project an image of the pattern onto the photosensitive substrate.
The plurality of projection optical systems are arranged in two rows along a non-scanning direction orthogonal to the scanning direction ,
The mark detection system includes a plurality of mark detection devices that detect a group of marks arranged along the non-scanning direction among the plurality of marks,
8. The position detection system includes a plurality of position detection devices arranged along the non-scanning direction and each detecting a position of the photosensitive substrate in the optical axis direction. An exposure apparatus according to claim 1.   The exposure apparatus according to claim 1, wherein the pattern is projected and exposed onto the photosensitive substrate having an outer diameter larger than 500 mm. In a method for manufacturing a device having a circuit pattern,
An exposure step of scanning and exposing the circuit pattern on a photosensitive substrate using the exposure apparatus according to any one of claims 1 to 9,
A development step of developing the photosensitive substrate on which the circuit pattern is exposed in the exposure step.

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