JP5465024B2 - Exposure apparatus and exposure method - Google Patents

Description

  The present invention relates to an exposure apparatus and an exposure method. More specifically, the present invention relates to a mask pattern on a workpiece by exposing the workpiece coated with a photosensitive agent by irradiating exposure light through a mask having a mask pattern formed thereon. The present invention relates to an exposure apparatus and an exposure method for transferring the image.

  As a conventional exposure method, a contact exposure method in which exposure light is irradiated in a state where a workpiece and a mask are in close contact with each other has been proposed (for example, see Patent Document 1). In the contact exposure apparatus described in Patent Document 1, a hoop-shaped workpiece is fed to an exposure position using an unwinding device and a winding device, and a front mask and a back mask having a predetermined transfer pattern on the front and back surfaces of the workpiece are used. After alignment adjustment, the work and the front and back masks are brought into close contact with each other. The mask transfer pattern is exposed and transferred onto the front and back surfaces of the workpiece by irradiating the mask with exposure light.

  In addition, as an illumination optical system of the exposure apparatus, the curvature of a reflecting mirror such as a collimation mirror (concave mirror) or a plane mirror is manually adjusted to cope with correction of distortion aberration of the mirror itself, expansion and contraction of the mask, and waviness of the workpiece. Various mechanisms have been devised to change locally (feed screw or the like) or automatically (piezoelectric element or the like) (see, for example, Patent Documents 2 to 6). For example, in the collimation mirror described in Patent Document 2, the center portion of the back surface of the mirror is fixedly supported, and each side portion is movably supported by a bracket. Then, the alignment mark is observed using an alignment camera, and the bracket is displaced via a male screw by a motor, whereby the collimation mirror is displaced, and the declination angle is changed every time exposure is performed.

JP 2005-92027 A JP 2005-129785 A Japanese Patent Application Laid-Open No. 07-201711 JP 09-304940 A JP 2001-042281 A JP 2003-077783 A

  By the way, in the contact exposure apparatus as described in Patent Document 1, the hoop-like work is formed in a flat plate shape so as to be in close contact with the front and back masks at the exposure position, but at this time, the work is distorted and the exposed area is rectangular. Instead, it may be a parallelogram. In this case, even when the alignment between the workpiece and the mask is adjusted, there is a problem that a deviation occurs between the mask pattern and the exposed region of the workpiece, resulting in a reduction in exposure accuracy.

  In addition, the conventional mechanisms for changing the curvature of the collimation mirror and the plane mirror described in Patent Documents 2 to 6 are not considered to correspond to the shape of the exposed area due to distortion of the workpiece. In addition, since these mechanisms are all displaced by an amount of the order of 100 μm, they cannot sufficiently cope with the shape of the workpiece.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to enable exposure and transfer of a mask pattern with high accuracy according to the shape of an exposed area of a workpiece even when the workpiece is distorted. An apparatus and an exposure method are provided.

The above object of the present invention can be achieved by the following constitution.
(1) An exposure method in which a work is irradiated with a light beam of exposure light from a light source through a mask, and the pattern of the mask is transferred to the work.
Detecting an alignment mark of the workpiece and an alignment mark of the mask with an alignment detection system;
A step of calculating a positional deviation amount of the mask and the workpiece and a distortion amount of the workpiece based on a deviation amount of the alignment marks detected by the alignment detection system;
Adjusting the alignment between the workpiece and the mask based on the calculated amount of displacement;
Correcting the curvature of the reflecting mirror that reflects the luminous flux of the exposure light from the light source based on the calculated strain amount at the same time as the alignment adjustment step or at a separate timing; and
With
The step of correcting the curvature of the reflector includes
Irradiating light having directivity toward the reflecting mirror from the exposure surface side of the reflecting mirror;
Imaging the light having the directivity reflected on the reflector by the imaging means via the reflector;
Detecting a displacement amount of the light having the directivity imaged when the curvature of the reflecting mirror is corrected;
And the curvature correction is performed so that the displacement amount corresponds to the calculated strain amount.
(2) The light having the directivity is irradiated from the reflection mirror toward the reflection mirror from the exposure surface side in the optical path of the light beam of the exposure light,
The exposure method according to (1), wherein the reflector is disposed in the vicinity of the integrator.
(3) The exposure method according to (2), wherein the reflecting plate is retracted from the optical path of the light beam when the mask is irradiated with the light beam of exposure light from the light source.
(4) The exposure method according to (2) or (3), wherein the imaging unit is arranged at a position away from an optical path of a light beam of exposure light from the light source.
(5) The alignment detection system includes at least two or more alignment detection systems arranged in the vicinity of the end of the rectangular mask.
In the vicinity of each alignment detection system, laser light sources that irradiate laser light as the light having the directivity are arranged in the same number or more as the number of the alignment detection systems (2) to ( The exposure method according to any one of 4).
(6) A plurality of laser light sources that respectively irradiate laser light as the light having the directivity, and the laser light that is provided corresponding to the plurality of laser light sources and reflected by the reflecting mirror are applied to the reflecting plate. And a collection mirror group including a plurality of mirrors that respectively reflect toward the
The plurality of laser light sources irradiate the laser light toward the reflection mirror from the exposure surface side of the reflection mirror outside the optical path of the light beam of the exposure light,
The exposure method according to (1), wherein the imaging unit images the laser beam reflected on the reflection plate via the reflection mirror and the condenser mirror group.
(7) At least after the alignment adjustment step, a step of redetecting the alignment mark of the workpiece and the alignment mark of the mask with an alignment detection system;
Determining whether or not the positional deviation amount between the mask and the workpiece calculated based on the re-detected deviation amount between the alignments in the calculation step is less than or equal to an allowable value;
With
The exposure method according to any one of (1) to (6), wherein, in the determination step, the alignment adjustment step is executed when a positional deviation amount between the mask and the workpiece exceeds the allowable value.
(8) The exposure method according to any one of (1) to (7), wherein a predetermined gap is provided between the mask pattern and the workpiece.
(9) The exposure method according to (8), wherein a transmission medium capable of transmitting the exposure light and in close contact with the workpiece at the time of exposure is attached to a lower surface of the mask.
(10) A work support unit that supports a work, a mask support unit that supports a mask, a feed mechanism that relatively moves the work and the mask, a light source, and a light beam of exposure light from the light source is reflected. An illumination optical system including a reflecting mirror, and an alignment detection system that detects an alignment mark of the workpiece and an alignment mark of the mask, and a beam of exposure light from the light source is applied to the workpiece through the mask. An exposure apparatus that irradiates and transfers the pattern of the mask onto the workpiece,
A light source for detection that irradiates light having directivity from the exposure surface side toward the reflecting mirror from the reflecting mirror, a reflecting plate on which the light having directivity reflected by the reflecting mirror is projected, and the reflection An imaging means for imaging the light having the directivity reflected on the reflector through a mirror, and a displacement amount of the light having the directivity imaged when the curvature of the reflector is corrected. And a curvature correction amount detection system having a control unit,
The illumination optical system includes a support mechanism that supports either the peripheral edge or the back surface of the reflecting mirror, and a drive unit that can move the support mechanism.
The feed mechanism relatively moves the workpiece and the mask based on a positional deviation amount between the mask and the workpiece calculated from a deviation amount between the alignment marks detected by the alignment detection system. Then, while adjusting the alignment between the workpiece and the mask,
The reflection mirror is such that the displacement amount of the light having the directivity detected by the curvature correction amount detection system when the curvature of the reflection mirror is corrected corresponds to the calculated strain amount of the workpiece. An exposure apparatus, wherein the curvature is corrected by moving the support mechanism by the driving means.
(11) The detection light source irradiates light having the directivity from an exposure surface side toward the reflection mirror from the reflection mirror in an optical path of the light beam of the exposure light,
The exposure apparatus according to (10), wherein the reflector is disposed in the vicinity of the integrator of the illumination optical system so as to be retractable from the optical path of the light beam of the exposure light.

  According to the exposure method and the exposure apparatus of the present invention, the amount of displacement between the mask and the workpiece and the amount of distortion of the workpiece are calculated based on the amount of displacement between the workpiece and the mask alignment mark detected by the alignment detection system. Reflection that reflects the light flux of the exposure light from the light source based on the calculated distortion amount at the same time as the alignment adjustment or at a different timing, while adjusting the alignment between the workpiece and the mask based on the positional deviation amount. Since the curvature of the mirror is corrected, the mask pattern can be accurately exposed and transferred in accordance with the shape of the exposed area of the workpiece even when the workpiece is distorted.

  Further, the curvature correction of the reflecting mirror is performed by irradiating light having directivity from the exposure surface side toward the reflecting mirror from the reflecting mirror, and imaging the light having directivity reflected on the reflecting plate through the reflecting mirror. Since the displacement amount of the light having directivity that is imaged when the curvature of the reflecting mirror is corrected is detected, the curvature correction is performed so that the displacement amount corresponds to the calculated strain amount. It is possible to reliably perform the curvature correction of the reflecting mirror corresponding to the strain amount of the work while imaging the displacement amount of the light having.

It is the schematic for demonstrating the double-sided exposure apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the mask support mechanism of FIG. It is a figure which shows an alignment mechanism, (a) is the front view, (b) is III-III sectional drawing of (a), (c) is III'-III 'sectional drawing of (a). (D) is a sectional view taken along line III ″ -III ″ of (b). It is a figure which shows the illumination optical system and curvature correction amount detection system of FIG. (A) is a front view which shows the reflecting mirror support structure of an illumination optical system, (b) is sectional drawing along the VV line of (a), (c) is V of (a). It is sectional drawing along line '-V'. It is a figure which shows the state which act | operated the support mechanism of the reflecting mirror support structure of FIG. It is a figure which shows the modification of the reflecting mirror support structure of an illumination optical system. It is a figure which shows the flowchart of the exposure method of this embodiment. It is a figure which shows the positional relationship of the mask and workpiece | work after alignment adjustment. (A) is a figure which shows the state before correct | amending the curvature of a reflective mirror, (b) is an imaging figure of the left camera of (a), (c) is a right figure of (a). It is an imaging figure of a camera. (A) is a figure which shows the state after correcting the curvature of a reflective mirror, (b) is an image pick-up figure of the left camera of (a), (c) is a right figure of (a). It is an imaging figure of a camera. It is a figure which shows the displacement amount of the laser beam projected on a reflecting plate. It is a figure which shows the modification of the curvature correction amount detection system of this invention.

  Hereinafter, an exposure apparatus and an exposure method according to embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
First, the double-sided exposure apparatus according to the first embodiment will be described with reference to FIG. 1. In the figure, reference numeral 11 denotes an unwinding apparatus for unwinding a work 12 such as a hoop material by tact feed in the horizontal direction, and 13 is an exposure. It is a winding device that is arranged on the downstream side of the position P and winds the workpiece 12 after exposure.

  A gantry 14 is installed between the unwinding device 11 and the winding device 13 along the conveying direction of the workpiece 12, and the unwinding device 11 side and the winding device are disposed at both ends in the longitudinal direction of the gantry 14. Support rolls 15a and 15b are attached as work support portions for supporting the work 12 in a substantially horizontal direction on the 13th side.

  An indexer table 16 is slidably provided along the conveyance direction of the workpiece 12 on the gantry 14, and a first indexer 17 is provided at the upstream end of the exposure position P of the indexer table 16. Is attached so as to be movable in the conveying direction of the workpiece 12, and a second indexer 18 is attached to an end portion on the downstream side.

  The second indexer 18 is arranged in the vicinity of the downstream side of the exposure position P, and the first indexer 17 is arranged at a position separated by the stroke + α of the indexer table 16 on the upstream side of the exposure position P. A support roll 19 for reducing the bending of the work 12 as much as possible is provided in the vicinity of the upstream side so as not to interfere with the first indexer 17. The stroke is not less than the width of the exposed portion in the feeding direction, but is preferably as close to this width as possible in order to improve the yield of the material.

  Each of the indexers 17 and 18 does not interfere with the mask support mechanism 53 of FIG. 2 in which the second indexer 18 supports the front mask 21 and the back mask 22 when the indexer table 16 is located at the leftmost position in FIG. In addition, the first indexer 17 (shown by a two-dot chain line) when the indexer table 16 is located at the rightmost position in FIG. After exposure, the workpiece 12 is clamped (for example, using an air cylinder), and the indexer table 16 is sent to the downstream side with a predetermined feed amount to convey the workpiece 12 in the same direction so that a new exposed portion is formed. It is arranged at the exposure position P.

After the conveyance, after completion of alignment, mask contact, etc., the clamp of the work 12 by the indexers 17 and 18 is released, and the indexer table 16 returns to the original position.
The unwinding device 11 unwinds the workpiece 12 and the winding device 13 winds the workpiece 12 according to the feed amount of the workpiece 12 by the indexers 17 and 18. Reference numeral 12a denotes a workpiece feed buffer provided on the unwinding device 11 side and the winding device 13 side.
Further, the first indexer 17 side of the indexer table 16 is pushed back against the workpiece 12 between the indexers 17 and 18 sent to the exposure position P by pushing the first indexer 17 upstream. A cylinder device 20 for applying tension is installed.

That is, the main body (housing) of the cylinder device 20 is fixed on the indexer table 16, and the extendable rod of the cylinder device 20 protrudes from the left end of the main body in FIG. 1, and the tip is fixed to the indexer 17. .
Here, the operation of clamping the workpiece and applying the back tension will be described.
First, as shown by the solid line in FIG. 1, the workpiece 12 is clamped by the respective clamp portions of the indexers 17 and 18 in a state where the indexer table 16 is returned to the original position. At this time, since the support roll 19 supports the workpiece 12 from below in the vicinity of the center of the indexers 17 and 18, the deflection of the workpiece 12 between the indexers 17 and 18 is suppressed to be small.

Next, the cylinder device 20 is operated, and the indexer 17 is pressed leftward with a predetermined force in FIG. Thereby, the bending amount of the workpiece | work 12 between each indexer 17 and 18 can be suppressed further smaller.
The pressing force by the cylinder device 20 is set to a minimum size necessary for suppressing the bending due to the weight of the workpiece 12 as described above, so that an excessive force is not applied to the workpiece 12. Thus, the clamping and the back tension application are completed.

  As shown in FIG. 2, on the front and back surfaces of the exposed portion of the workpiece 12 at the exposure position P, a mask support portion for supporting a front mask 21 and a back mask 22 each having a predetermined transfer pattern, and a mask as a feed mechanism A support mechanism 53 is provided. The mask support mechanism 53 includes mask adjustment bases 34a and 34b, slide bearings 35a and 35b, mask bases 36a and 36b, and an alignment mechanism 49 provided on the mask bases 36a and 36b. The front mask 21 and the rear mask 22 are adsorbed to the mask adjustment bases 34a and 34b by vacuuming and are detachably attached. The mask adjustment bases 34a and 34b are connected to the mask bases 36a and 36b via the slide bearings 35a and 35b in order to perform alignment between the masks 21 and 22, respectively, in the X-axis direction, Y-axis direction, and θ-direction (X, Y It is supported so that it can be moved slightly in the direction of rotation in the plane).

  Specifically, as shown in FIG. 3, a mask adjustment base 34 a and a plurality of talcite support members 82 are attached to the mask base 36 a with a plurality of bolts 83 sandwiching the mask base 36 a. The mask base 36a is formed with an insertion hole 36a1 into which the bolt 83 is inserted with a gap. The insertion hole 36a1 has a height between the turkeyite support member 82 and the mask adjustment base 34a around the bolt 83. A collar 84 to be determined is arranged. A turkite 35a as a slide bearing is attached to the surface of the turkite support member 82 facing the mask base 36a and the surface of the mask base 36a facing the mask adjustment base 34a. Accordingly, the mask adjustment base 34a is supported so as to be slightly movable with respect to the mask base 36a in the X-axis direction, the Y-axis direction, and the θ direction (rotation direction in the X and Y planes). Further, of the two talcite support members 82a and 82b facing each other in the X-axis direction through the opening of the mask base 36a, one of the talcite support members 82a has a drive unit 85a that drives as the alignment mechanism 49 in the Y-axis direction. A drive unit 85b for driving in the X-axis direction, and a preload unit 86a for applying a predetermined preload to the turkite support member 82a, and the other talcite support member 82b has a drive unit 85c for driving in the Y-axis direction, And preload units 86b and 86c for applying a predetermined preload to the turkite support member 82b. Further, around one bolt 83 of the turkite support members 82a and 82b, there is another collar 87 between the turkite support members 82a and 82b and the collar 84 and between the mask adjustment base 34a and the collar 84. It is sandwiched. Accordingly, the mask adjustment base 34a can be moved slightly in the X-axis direction by driving the drive unit 85b, and the mask adjustment base 34a can be moved slightly in the Y-axis direction by driving the drive units 85a and 85c synchronously. The mask adjustment base 34a can be slightly moved in the θ direction by relatively driving the drive units 85a and 85c in the Y-axis direction. Further, since the turkeyite supporting members 82a and 82b pressed by the drive units 85a, 85b and 85c are provided with other collars 87, the turkeyite supporting members 82a and 82b, the mask adjustment base 34a, and the collar 84 It prevents backlash and improves responsiveness repeatedly. The same applies to the mask support mechanism 53 that supports the back mask 22.

  A transfer pattern P is formed of chrome on the surface of the front mask 21 and the back mask 22, and a photomask film (transparent film) 80 having a predetermined thickness is attached (see FIG. 10). ). The front mask 21 and the back mask 22 may be provided with a transmissive medium capable of transmitting exposure light by providing a predetermined gap between the masks 21 and 22 and the work 12. It is not limited and may be glass. Furthermore, a shim material may be affixed to the outer peripheral part used as a non-exposure area, and an air gap may be formed.

  The mask bases 36a and 36b are fixed to the Z-axis frames 37a and 37b. The mask adjustment bases 34a and 34b, the mask bases 36a and 36b, and the Z-axis frames 37a and 37b have holes, so that the irradiation light from the illumination optical systems 60a and 60b can be applied to the front and back masks 21 and 22. It has become. The illumination optical systems 60a and 60b are also configured to be movable in the Z-axis direction.

  The bottoms of the Z-axis frames 37a and 37b are supported by Z-axis stages 41a and 41b fixed on the double-sided exposure unit base 40 via Z-axis linear bearings 39a and 39b, and are supported by Z-axis drive units 42a and 42b. It is configured to be driven and move on the Z-axis stages 41a and 41b in the Z-axis direction. That is, the Z-axis drive units 42a and 42b include Z-axis drive motors 43a and 43b, ball screws 44a and 44b connected to the rotation shafts of the Z-axis drive motors 43a and 43b, and struts 45a that support the ball screws 44a and 44b. 45b, drive joints 46a and 46b attached to the Z-axis frames 37a and 37b, and nuts 47a and 47b embedded in the drive joints 46a and 46b and screwed into the ball screws 44a and 44b.

  Under such a configuration, when the ball screws 44a and 44b rotate in conjunction with the rotation of the Z-axis drive motors 43a and 43b, the Z-axis frames 37a and 37b are operated by the action of the ball screws 44a and 44b and the nuts 47a and 47b. Is moved in the Z-axis direction together with the drive joints 46 a and 46 b, and the masks 21 and 22 are brought into close contact with both surfaces of the work 12.

  The Z-axis frames 37a and 37b on the front and back sides are each provided with four positioning adjustment screws 50 or deformation amount absorbing spacers 51 as support members, and the mask bases 36a and 36b are fixed via these. It has come to be. In FIG. 2, for convenience, a positioning adjustment screw 50 is shown on the front side, and a deformation amount absorbing spacer 51 is shown on the back side. The positioning adjustment screw 50 and the deformation amount absorbing spacer 51 are used to eliminate the twisting of the front and back masks 21 and 22 caused by the twisting of the front and back Z-axis frames 37a and 37b that occurred during processing or assembly. Is. The deformation amount absorbing spacer 51 is processed in advance to a desired thickness in consideration of processing errors and deformation of the Z-axis frames 37a and 37b, and the positioning adjustment screw 50 is adjusted by adjusting the screw in and out. The distance between the Z-axis frames 37a and 37b and the mask bases 36a and 36b can be adjusted.

  Further, as shown in FIG. 2, a plurality of alignment detection systems 52 (in this embodiment, on the side opposite to the work 12 with respect to the masks 21 and 22, can be advanced and retracted to positions where the alignment marks on the mask side can be visually recognized. A total of four) are provided in the vicinity of the four corners of the rectangular mask. Each alignment detection system 52 includes a CCD camera 55, an objective lens 56, a mirror 57, and irradiation means (not shown). The CCD camera 55 uses the mask-side alignment marks 21a and 22a (FIG. 10). In this case, only 21a is shown) and the workpiece side alignment mark 12b is imaged. Each alignment detection system 52 that has advanced to a position where the mask alignment mark can be visually recognized moves in synchronization with the mask adjustment bases 34a and 34b so as to image the mask alignment marks 21a and 21b from above.

  Accordingly, the alignment mechanism 49 captures and detects the corresponding alignment marks 21a and 22a formed on the front and back masks 21 and 22 and the alignment mark 12b of the workpiece 12, and the alignment mechanism 49 allows the front and back masks 21 to be detected. , 22 is adjusted. Note that the front and back masks 21 and 22 may be aligned by driving and controlling the alignment mechanism 49 so that the alignment marks 21a and 22a of the masks 21 and 22 overlap each other.

  As shown in FIG. 4, the illumination optical systems 60a and 60b include, for example, a high pressure mercury lamp 61a that is a light source for ultraviolet irradiation, and a reflector 61b that collects the light emitted from the high pressure mercury lamp 61a. The lamp unit 61, the flat mirror 62 for changing the direction of the optical path EL, the exposure control shutter unit 64 for controlling the opening and closing of the irradiation optical path, and the downstream side of the exposure control shutter unit 64, are condensed by the reflector 61b. The optical integrator 65 that emits the emitted light so as to have as uniform an illuminance distribution as possible in the irradiation region, the plane mirror 63 for changing the direction of the optical path EL emitted from the integrator 65, and the light from the high-pressure mercury lamp 61a A collimation mirror 67 that irradiates the parallel light as parallel light, and It comprises a plane mirror 66 to irradiate the click M, the. Note that a DUV cut filter, a polarization filter, and a band pass filter may be disposed between the optical integrator 65 and the exposure surface. Further, the light source may be a single lamp as a high-pressure mercury lamp, or may be constituted by an LED.

  When the exposure control shutter unit 64 is controlled to be opened at the time of exposure, the light emitted from the multi-lamp unit 61 passes through the plane mirror 62, the optical integrator 65, the plane mirror 63, the collimation mirror 67, and the plane mirror 66. Then, the masks 21 and 22 held by the mask support mechanism and the surface of the substrate W are irradiated as light for pattern exposure, and the exposure pattern of the mask M is exposed and transferred onto the substrate W.

Here, as shown in FIG. 5, the plane mirror 66 is made of a glass material formed in a rectangular shape in front view. A plurality of support mechanisms 71 fixed to a support mechanism holding frame 70 are provided as reflector reflecting structures at three locations near the center of the back surface of the flat mirror 66 and 16 peripheral portions. In the support mechanism 71 provided in the vicinity of the center, the support portion 72 is fixed to the back surface of the flat mirror 66 with an adhesive, and in the support mechanism 71 provided in the peripheral portion, the support portions 72 and 72 a are provided on the flat mirror 66. It is fixed with an adhesive so as to sandwich the front and back surfaces. Further, a ball joint 74 as a bending mechanism that allows bending of ± 0 · 5 deg or more is provided at a position near each of the support portions 72 and 72 a of each support mechanism 71, and is opposed to the support mechanism holding frame 70. A motor 75 as a driving means is attached to the end on the support side.
Note that the support mechanism 71 at the center of the plane mirror 66 may be fixed to the support mechanism holding frame 70.

  Further, guide members 76 and 77 are attached to the rectangular support mechanism holding frame 70 at positions on two sides orthogonal to each other, and the side surface of the support portion 72a facing the guide members 76 and 77 is rolled. A moving member 78 is attached. Further, a low friction mechanism 79 such as Teflon (registered trademark) is applied to the guide surfaces 76 a and 77 a of the guide members 76 and 77 that guide the rolling member 78.

  Further, a plurality of contact sensors 81 are attached to the back surface of each position of the flat mirror 66 that reflects the exposure light at the positions of the mask side alignment marks 21a and 22a.

  Accordingly, the plane mirror 66 drives each motor 75 of each support mechanism 71 provided on the support mechanism holding frame 70 while sensing the amount of displacement of the plane mirror 66 by the contact sensor 81, whereby each support mechanism 71. Changes its length and moves the support 72 linearly. The flat mirror 66 is guided by the two guide members 76 and 77 through the rolling member 78 provided on the support portion 72 and the curvature thereof is locally corrected due to the difference in length of each support mechanism 71. In addition, the declination angle of the plane mirror 66 can be corrected. At this time, as shown in FIG. 6, each support mechanism 71 is provided with a ball joint 74, so that the part on the support part side can be rotated three-dimensionally. It can be tilted along the surface of the plane mirror 66. For this reason, it is suppressed that the stress in the vicinity of each support part 72 of the plane mirror 66 between each support part 72 from which a movement amount differs is large. Accordingly, even when the average breaking stress value is made of a glass material, when the curvature of the plane mirror 66 is locally corrected, the stress generated in the glass can be made smaller than in the conventional case. The flat mirror 66 can be bent on the order of 10 mm without breakage, and the curvature can be greatly changed.

  As shown in FIG. 7, each support mechanism 71 may have a plurality of (two in FIG. 7) ball joints 74. In this case, the amount of bending of the plane mirror 66 is set to each hole joint. The total amount of rotation by 74 can be made, and the plane mirror 66 can be bent more greatly.

  In the present embodiment, a curvature correction amount detection system 90 is provided for determining whether or not the curvature correction of the plane mirror 66 corresponding to the strain amount of the workpiece 12 has been performed when the curvature of the plane mirror 66 is corrected. It has been. The curvature correction amount detection system 90 is disposed in the vicinity of each alignment detection system 52, and extends from the flat mirror 66 to the flat mirror 66 from the exposure surface side (in the present embodiment, near the mask) in the optical path EL of the exposure light beam. A plurality of (four in the present embodiment) laser pointers 91 that irradiate laser light L as light having directivity toward the light source EL and can be retracted from the optical path EL of the light beam of the exposure light in the vicinity of the integrator 65 And a camera 93 as an imaging means for imaging the laser light L reflected on the reflector 92 via the reflector 92 disposed on the plane and the plane mirror 66, and a motor 75 of the support mechanism 71 for the camera 93 and the plane mirror 66. Are detected, and displacement amounts S1 and S2 of the laser light L imaged when the curvature of the plane mirror 66 is corrected are detected. Has calculated the strain amount and the control unit 94 for controlling the motor 75 of the support mechanism 71 so as to correspond, the.

  The laser pointer 91 is attached to the upper part of the alignment detection system 52, for example, the CCD camera 55, and moves in synchronization with the movement of the alignment detection system 52 to a position where the alignment mark on the mask side can be visually recognized. The laser pointer 91 may be moved back and forth above the mask by a drive mechanism independent of the alignment detection system 52.

  Since the reflecting plate 92 is arranged in the vicinity of the integrator that is the most condensed light by being reflected by the collimation mirror 67, the four laser pointers reflected by the plane mirror 66, the collimation mirror 67, and the plane mirror 63. The laser beam L from 91 can be captured by the reflector 92 having a relatively small area. Further, the reflector 92 is disposed so as to be retractable from the optical path EL of the light beam by a driving mechanism (not shown) when the masks 21 and 22 are irradiated with the light beam of the exposure light from the light source during normal exposure. Furthermore, the reflection plate 92 is a reflective surface having a low reflectance, so that the visibility of the laser light L with the camera 93 can be improved.

  The camera 93 is disposed at a position away from the light path EL of the light beam from the light source so as not to affect the light beam of the exposure light.

  Further, the control unit 94 detects the position of the laser light L imaged by the camera 93 as the displacement amounts S1 and S2 before and after the curvature correction, and the displacement amounts S1 and S2 are the strain amounts α of the workpiece 12. , Β is confirmed, and a control signal is given to the motor 75 of the support mechanism 71 of the plane mirror 66.

  Next, the exposure method of this embodiment will be described with reference to FIGS. 10 and 11 schematically show the case where the upper surface of the workpiece 12 is exposed, and the case where the lower surface of the workpiece 12 is exposed in the same manner is not shown. Here, when the hoop-shaped workpiece 12 is formed into a flat plate at the exposure position P, the workpiece 12 may be distorted and the exposed area may not be rectangular but may be a parallelogram (see FIG. 9). In the following, the case where such a workpiece 12 is exposed will be described. However, FIGS. 10 and 11 show the CCD camera 55 at a diagonal position of the workpiece.

  First, the workpiece 12 is conveyed to the exposure position P where the front and back masks 21 and 22 are located (step S1), and the alignment mark 12b of the workpiece 12 and the alignment marks 21a of the masks 21 and 22 are detected by the four CCD cameras 55. (Step S2). Then, based on the shift amount of the alignment marks 12b and 21a detected by each CCD camera 55 by a control unit (not shown), the positional shift amount between the centers of the masks 21 and 22 and the center of the work 12, and the distortion of the work 12 The quantity is calculated separately. Then, it is determined whether or not the amount of positional deviation between the centers of the masks 21 and 22 and the center of the workpiece 12 and the strain amount of the workpiece 12 are not more than allowable values (step S3).

  When the amount of positional deviation between the center of the masks 21 and 22 and the center of the workpiece 12 exceeds the allowable value, the correction amount by the alignment mechanism 49 is calculated as a command value, and the distortion amount of the workpiece 12 exceeds the allowable value. If there is, the correction amount of the plane mirror 66, specifically, the movement amount of each support mechanism 71 is calculated as a command value.

  In step S4, the alignment mechanism 49 for aligning the front and back masks 21 and 22 is driven and controlled to align the workpiece 12 and the masks 21 and 22 (shift correction). As a result, for example, as shown in FIG. 9, the sum of the positional deviation amounts of the centers of the alignment cameras 52, that is, the alignment marks 21a of the masks 21 and 22, and the alignment marks 12b of the workpiece 12, is minimized. The misalignment between the alignment marks 21 a of 21 and 22 and the alignment mark 12 b of the work 12 is mainly caused by distortion of the work 12.

  Next, in step S5, in order to correspond to the shape of the exposed area of the workpiece 12, the curvature of the plane mirror 66 is corrected to correct the declination angle of the exposure light. Specifically, based on the strain amounts α and β of the workpiece 12 as shown in FIG. 10, a command value related to the movement amount of each support mechanism 71 is sent to each motor 75, and the displacement of the plane mirror 66 is moved by the contact sensor 81. Each motor 75 is driven and controlled while checking the amount.

  Further, at the time of this curvature correction, the reflecting plate 92 is advanced on the optical path of the light beam of the exposure light, and the laser pointer 91 of the alignment detection system 52 located above the mask 21 is directed toward the flat mirror 66 to emit the laser light L. Irradiate. As a result, the camera 93 causes the laser light L before the curvature correction (black circle in the figure) reflected on the reflection plate 92 and the laser light L ′ after the curvature correction (white circle in the figure) as shown in FIG. And image.

  Then, after the correction by the alignment mechanism 49 and the correction by the plane mirror 66 are performed, the alignment mark 12b of the workpiece 12 and the alignment marks 21a of the masks 21 and 22 are again set by the four CCD cameras 55 in step S2. To detect. Here, as apparent from FIGS. 11B and 11C, the CCD camera 55 is located on the optical path side of the masks 21 and 22, and therefore cannot receive light via the plane mirror 66. For this reason, the CCD camera 55 cannot detect the positions of both alignment marks corrected by the bending correction of the plane mirror 66, and after correction by the alignment mechanism 49, as in FIGS. 10B and 10C. The alignment mark 12b of the workpiece 12 and the alignment marks 21a of the masks 21 and 22 are detected. Accordingly, in step S3 after correction, it is determined whether or not the correction amount by the alignment mechanism 49 based on the positional deviation amount between the centers of the masks 21 and 22 and the center of the work 12 is equal to or less than an allowable value.

  In step S3, the control unit 94 detects the positions of the laser beams L and L ′ captured by the camera 93 as the displacement amounts S1 and S2 before and after the curvature correction, and the displacement amounts S1 and S2. Corresponds to the strain amounts α and β of the workpiece 12, specifically, the displacement amounts S1 and S2 of the laser beams L and L ′ are allowable with respect to the values corresponding to the strain amounts α and β of the workpiece 12. Check if it is within range. A control signal is given to the motor 75 of the support mechanism 71 of the plane mirror 66 until the displacement amounts S1 and S2 fall within an allowable range of values corresponding to the strain amounts α and β of the workpiece 12. Curvature correction is performed.

  Thereafter, when the positional deviation amount and the distortion amount calculated in step S3 are equal to or less than the allowable values, the process proceeds to step S6, and the transparent films 80 of the masks 21 and 22 are brought into close contact with the front and back surfaces of the workpiece 12. Then, the illumination optical systems 60a and 60b respectively arranged on the outer sides of the masks 21 and 22 are connected to the masks 21 and 22 via a transparent film 80 that gives a predetermined gap between the masks 21 and 22 and the workpiece 12. The exposure light is irradiated toward the exposed area A (for example, the ground pattern) of the workpiece 12 via the transparent film 80. As a result, the patterns of the masks 21 and 22 are exposed and transferred onto the front and back surfaces of the work 12 in a state where the pattern of the masks 21 and 22 matches the shape of the exposed area A of the work 12. At the time of exposure, since the workpiece 12 at the exposure position P is held by the masks 21 and 22, the clamping of the workpiece 12 by the indexers 17 and 18 and the application of tension to the workpiece 12 by the cylinder device 20 are released.

  After the exposure transfer, the indexer table 16 is sent downstream by a predetermined feed amount with the workpiece 12 clamped by the indexers 17 and 18, and the workpiece 12 is conveyed in the same direction. Then, a new exposed portion is placed at the exposure position P (step S7), and after the transfer, the clamp of the work 12 by the indexers 17 and 18 is released to return the indexer table 16 to the original position. The workpiece 12 sent to the exposure position P is clamped by the indexers 17 and 18 to reduce the displacement amount of the workpiece 12, and a back tension is applied to the workpiece 12 by the cylinder device 20, and a new process is performed through the same process as described above. Exposure transfer is performed.

  Therefore, according to the exposure method of the present embodiment, the step of detecting the alignment mark 12b of the workpiece 12 and the alignment marks 21a and 22a of the masks 21 and 22 by the alignment detection system 52 and the both detected by the alignment detection system 52 are performed. Based on the displacement amounts of the alignment marks 12b, 21a, 22a, a step of calculating the displacement amount between the workpiece 12 and the masks 21, 22 and the strain amounts α, β of the workpiece 12, and based on the calculated displacement amounts. Then, at the same time as the process of adjusting the alignment between the workpiece 12 and the masks 21 and 22 and at the same time as the alignment adjustment process, the light flux of the exposure light from the light source is reflected based on the calculated distortion amounts α and β. Correcting the curvature of the plane mirror 66. Thereby, even when the work 12 is distorted, the patterns of the masks 21 and 22 can be accurately exposed and transferred in accordance with the shape of the exposed area A of the work 12.

  The curvature correction process of the plane mirror 66 includes a process of irradiating the plane mirror 66 with the laser light L from the exposure surface side to the plane mirror 66, and the laser beam L reflected on the reflector 92 via the plane mirror 66. And a step of detecting the displacement amounts S1 and S2 of the laser beams L and L ′ imaged when the curvature of the plane mirror 66 is corrected. The displacement amounts S1 and S2 Since the curvature correction is performed so as to correspond to the calculated distortion amounts α and β, the plane mirror 66 corresponding to the distortion amounts α and β of the workpiece 12 while imaging the displacement amounts S1 and S2 of the laser beams L and L ′. Curvature correction can be performed reliably.

  In addition, the laser light L is irradiated from the plane mirror 66 toward the plane mirror 66 from the exposure surface side in the optical path EL of the light beam of the exposure light, and the reflection plate 92 is disposed in the vicinity of the integrator. Can be planned.

  In addition, the reflecting plate 92 retracts from the optical path of the light beam when the masks 21 and 22 are irradiated with the light beam of the exposure light from the multi-lamp unit 61, so that the light beam of the exposure light is affected during the actual exposure operation. There is nothing.

  Furthermore, since the camera 93 is also arranged at a position away from the optical path of the light beam of the exposure light from the multi-lamp unit 61, it does not affect the light beam of the exposure light during the actual exposure operation.

  The alignment detection system includes four alignment detection systems 52 arranged in the vicinity of the four corners of the rectangular masks 21 and 22, and a laser pointer 91 that irradiates laser light L in the vicinity of each alignment detection system 52. Are arranged in the same number or more as the number of alignment detection systems 52. That is, since the laser pointer 91 is disposed in the vicinity of the four corners of the rectangular masks 21 and 22 in which the distortion amounts α and β of the workpiece 12 can be easily grasped, the curvature correction of the plane mirror 66 corresponding to the distortion amounts α and β is performed. It is possible to more efficiently check whether or not

  In addition, at least after the alignment adjustment step, the alignment marks 12b of the workpiece 12 and the alignment marks 21a and 22a of the masks 21 and 22 are re-detected by the alignment detection system, and the alignments 12b and 21a re-detected by the calculation step are detected. , 22a, and a step of determining whether the positional shift amount of the masks 21 and 22 calculated based on the shift amount of the workpiece 12 is equal to or less than an allowable value. In the determination step, the masks 21 and 22 and the workpiece 12 are determined. Since the alignment adjustment process is executed when the amount of positional deviation exceeds the allowable value, exposure transfer can be performed with higher accuracy.

  In addition, since a predetermined gap is provided between the transfer pattern drawn on the masks 21 and 22 and the workpiece 12, the light incident on the masks 21 and 22 depends on the declination angle caused by the bending of the plane mirror 66. Since it is bent by a predetermined gap, the mask pattern is projected in accordance with the distortion of the workpiece. Thereby, even when the work 12 is distorted, the patterns of the masks 21 and 22 can be accurately exposed and transferred in accordance with the shape of the exposed area A of the work 12.

  Since a transparent film 80 that can be in close contact with the workpiece 12 during exposure is attached to the lower surfaces of the masks 21 and 22, high-resolution exposure transfer can be realized by the contact exposure method, and the work 12 and the masks 21 and 22 can be connected to each other. By providing an interval between them, the curvature of the plane mirror 66 is changed to correct the declination angle, and the patterns of the masks 21 and 22 can be accurately exposed and transferred so as to correspond to the distortion of the work 12. .

  Further, based on the shift amounts of the alignment marks 12b, 21a, and 22a detected by the alignment detection system 52, the shift amount between the centers of the masks 21 and 22 and the center of the work 12 and the strain amount of the work 12 are calculated. The plane mirror 66 drives the plurality of support mechanisms 71 that support either the peripheral edge or the back surface of the plane mirror 66 by the motor 75 based on the calculated strain amount of the workpiece 12, thereby locally changing the curvature thereof. Therefore, the curvature of the plane mirror 66 can be easily corrected by driving and controlling the motor 75 of each support mechanism 71.

  Furthermore, according to the exposure apparatus of the present embodiment, the laser pointer 91 that irradiates the laser beam L from the plane mirror 66 toward the plane mirror 66 from the exposure surface side, and the laser beam L reflected by the plane mirror 66 are projected. Of the laser beam L and L ′ captured when the curvature of the plane mirror 66 is corrected, and the camera 93 that captures the laser beam L reflected on the reflector 92 via the reflector 92 and the plane mirror 66. A curvature correction amount detection system 90 having a control unit 94 for detecting the displacement amounts S1 and S2 is further provided, and the illumination optical systems 60a and 60b support a support mechanism 71 that supports either the peripheral edge or the back surface of the flat mirror 66. And a motor 75 that can move the support mechanism 71, and the mask support mechanism 53 is a matrix calculated from the amount of deviation of both alignment marks detected by the alignment detection system 52. The alignment between the workpiece 12 and the masks 21 and 22 is adjusted by moving the workpiece 12 and the masks 21 and 22 relative to each other based on the positional deviation amount between the workpieces 21 and 22 and the plane mirror 66. Is such that the displacement amounts S1 and S2 of the laser beams L and L ′ detected by the curvature correction amount detection system 90 when the curvature is corrected correspond to the calculated strain amounts α and β of the workpiece 12. The curvature is locally corrected by moving the support mechanism 71 by the motor 75. Thereby, even when the work 12 is distorted, the patterns of the masks 21 and 22 can be accurately exposed and transferred in accordance with the shape of the exposed area of the work 12.

  The laser pointer 91 irradiates a laser beam L from the plane mirror 66 toward the plane mirror 66 from the exposure surface side in the optical path EL of the light beam of the exposure light, and the reflection plate 62 is near the integrator 65 of the illumination optical systems 60a and 60b. Since the exposure light beam is disposed so as to be retractable from the optical path EL, space can be saved.

  In the above embodiment, the curvature of the plane mirror 66 is corrected after the alignment between the workpiece 12 and the masks 21 and 22 is adjusted. However, the alignment adjustment and the curvature correction of the plane mirror 66 are performed at the same time. Time may be shortened. Further, the curvature of the flat mirror 66 may be corrected after the transparent film 80 and the work 12 are brought into close contact after the alignment adjustment is performed a plurality of times and the positional deviation amount becomes equal to or less than the allowable value.

  FIG. 13 is a diagram showing a modification of the curvature correction amount detection system 90 of the present invention. This curvature correction amount detection system 90 is fixedly arranged to project a plurality of laser pointers 91 (laser light sources) that can be turned ON / OFF that respectively irradiate the laser light L and the laser light L reflected by the plane mirror 66. A condensing mirror group 96 provided with a plurality of mirrors 94 provided respectively corresponding to the reflecting plate 95 and the plurality of laser pointers 91 and reflecting the laser light L reflected by the plane mirror 66 toward the reflecting plate 95. And a camera 93 (imaging means) that images the laser light L reflected on the reflection plate 95 via the plane mirror 66 and the condenser mirror group 96.

  The plurality of laser pointers 91 are respectively installed on a laser installation frame 97 fixedly arranged so as to be substantially parallel to the plane mirror 66, and the laser beam L is exposed from the plane mirror 66 outside the optical path EL of the light beam of the exposure light. Irradiate from the side toward the plane mirror 66 at an angle. Also in the condensing mirror group 96, each mirror 94 is respectively installed on a mirror mounting frame 98 fixedly arranged on the same plane as the laser installation frame 97 so as to be substantially parallel to the plane mirror 66. . Each mirror 94 is driven to rotate about two axes orthogonal to each other in a plane so that the direction of each mirror 94 can be adjusted so that the laser beam L is condensed on a reflecting plate 95 smaller than the condenser mirror group 96. That is, it has an adjustment mechanism (not shown) having two degrees of freedom in the rotation direction. The camera 93 is mounted in a space that does not interfere with each mirror 94 near the center of the mirror mounting frame 98.

  Therefore, also in the curvature correction detection system 90 of this modified example, the amount of displacement of the plane mirror 66 before and after the curvature correction can be detected by the camera 93. In particular, in this curvature correction detection system 90, since the laser pointer 91, the condensing mirror group 96, and the reflecting plate 95 are fixedly arranged, detection with good reproducibility is possible. Further, since the curvature correction detection system 90 is arranged independently of the alignment detection system 52, the curvature correction process can be performed regardless of the position of the alignment detection system 52.

  The laser installation frame 97 is not limited to the arrangement substantially parallel to the plane mirror 66 as long as each laser pointer 91 can be irradiated to the plane mirror 66 with the same angle. Further, the mirror mounting frame 98, the reflecting plate 95, and the camera 93 can be arranged at arbitrary positions where these functions can be performed.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

  The reflecting mirror for correcting the curvature of the present invention is not limited to the plane mirror 66 of the above embodiment, and may be provided in another plane mirror 63 or a collimation mirror 67, and is applied to an arbitrary reflecting mirror. In addition, the curvature of a plurality of these mirrors 63, 66, 67 may be corrected. Further, when the curvature of a plurality of mirrors is corrected, the correction role can be shared for each mirror so that the scale correction is performed by the collimation mirror 67 and the distortion correction is performed by the plane mirror 66.

  The reflector 92 is provided separately from the shutter unit 64, but may be configured by the shutter unit 64 when the shutter unit 64 is on the downstream side of the integrator 65 on the optical path of the exposure light. .

Further, as the curvature correction amount detection system, the light applied to the reflecting plate is not limited to the laser light, but may be any light that emits a light beam smaller than the light beam of the directional exposure light.
Furthermore, the reflecting mirror curvature adjusting mechanism and the curvature correction amount detection system of the present invention can be applied not only to the proximity exposure apparatus and the contact exposure apparatus but also to an exposure apparatus other than the projection exposure apparatus that performs distortion correction with a lens system.
In addition, the detection light source for irradiating light having directivity according to the present invention is preferably disposed in the vicinity of the mask. However, the light source for detection may be disposed on the exposure surface side with respect to the reflecting mirror, and the work chuck side from the mask. May be arranged.

12 Workpiece 12b Workpiece side alignment mark 15a, 15b Support roll (work support part)
21, 22 Mask 21a Mask side alignment mark 49 Alignment mechanism 52 Alignment detection system 53 Alignment support mechanism (mask support part, feed mechanism)
60a, 60b Illumination optical system 61 Multi lamp unit (light source)
63, 66 Plane mirror (reflector)
67 Collimation mirror
71 Support mechanism 75 Motor (drive means)
80 Transparent film (transparent medium)
90 Curvature correction amount detection system 91 Laser pointer (laser light source, light source for detection)
92 Reflector 93 Camera 94 Controller

Claims (11)

An exposure method of irradiating a work with a light flux of exposure light from a light source through a mask, and transferring a pattern of the mask onto the work,
Detecting an alignment mark of the workpiece and an alignment mark of the mask with an alignment detection system;
A step of calculating a positional deviation amount of the mask and the workpiece and a distortion amount of the workpiece based on a deviation amount of the alignment marks detected by the alignment detection system;
Adjusting the alignment between the workpiece and the mask based on the calculated amount of displacement;
Correcting the curvature of the reflecting mirror that reflects the luminous flux of the exposure light from the light source based on the calculated strain amount at the same time as the alignment adjustment step or at a separate timing; and
With
The step of correcting the curvature of the reflector includes
Irradiating light having directivity toward the reflecting mirror from the exposure surface side of the reflecting mirror;
Imaging the light having the directivity reflected on the reflector by the imaging means via the reflector;
Detecting a displacement amount of the light having the directivity imaged when the curvature of the reflecting mirror is corrected;
And the curvature correction is performed so that the displacement amount corresponds to the calculated strain amount. The light having the directivity is irradiated toward the reflecting mirror from the exposure surface side of the reflecting mirror in the optical path of the light beam of the exposure light,
The exposure method according to claim 1, wherein the reflector is disposed in the vicinity of the integrator.   The exposure method according to claim 2, wherein the reflecting plate is retracted from an optical path of the light beam when the mask is irradiated with a light beam of exposure light from the light source.   4. The exposure method according to claim 2, wherein the imaging unit is disposed at a position away from the optical path of the light beam of the exposure light from the light source. The alignment detection system includes at least two or more alignment detection systems respectively disposed in the vicinity of the end of the rectangular mask.
5. The number of laser light sources that irradiate laser light as the light having the directivity is arranged in the vicinity of each alignment detection system, which is equal to or greater than the number of alignment detection systems. The exposure method according to any one of the above. A plurality of laser light sources each irradiating laser light as the light having the directivity, and provided corresponding to the plurality of laser light sources, respectively, the laser light reflected by the reflecting mirror toward the reflecting plate, respectively A collection mirror group including a plurality of mirrors to reflect,
The plurality of laser light sources irradiate the laser light toward the reflection mirror from the exposure surface side of the reflection mirror outside the optical path of the light beam of the exposure light,
2. The exposure method according to claim 1, wherein the imaging unit images the laser light reflected on the reflecting plate via the reflecting mirror and the condenser mirror group. A step of re-detecting the alignment mark of the workpiece and the alignment mark of the mask with an alignment detection system after at least the alignment adjustment step;
Determining whether or not the positional deviation amount between the mask and the workpiece calculated based on the re-detected deviation amount between the alignments in the calculation step is less than or equal to an allowable value;
With
The exposure method according to claim 1, wherein, in the determination step, the alignment adjustment step is executed when a positional deviation amount between the mask and the workpiece exceeds the allowable value.   The exposure method according to claim 1, wherein a predetermined gap is provided between the mask pattern and the workpiece.   9. The exposure method according to claim 8, wherein a transmission medium capable of transmitting the exposure light and in close contact with the workpiece during exposure is attached to a lower surface of the mask. A workpiece supporting portion for supporting a workpiece; a mask supporting portion for supporting a mask; a feed mechanism for relatively moving the workpiece and the mask; a light source; and a reflecting mirror for reflecting a light flux of exposure light from the light source. An illumination optical system, and an alignment detection system that detects an alignment mark of the workpiece and an alignment mark of the mask, and irradiates the workpiece with a light beam of exposure light from the light source through the mask, An exposure apparatus for transferring the mask pattern onto the workpiece,
A light source for detection that irradiates light having directivity from the exposure surface side toward the reflecting mirror from the reflecting mirror, a reflecting plate on which the light having directivity reflected by the reflecting mirror is projected, and the reflection An imaging means for imaging the light having the directivity reflected on the reflector through a mirror, and a displacement amount of the light having the directivity imaged when the curvature of the reflector is corrected. And a curvature correction amount detection system having a control unit,
The illumination optical system includes a support mechanism that supports either the peripheral edge or the back surface of the reflecting mirror, and a drive unit that can move the support mechanism.
The feed mechanism relatively moves the workpiece and the mask based on a positional deviation amount between the mask and the workpiece calculated from a deviation amount between the alignment marks detected by the alignment detection system. Then, while adjusting the alignment between the workpiece and the mask,
The reflection mirror is such that the displacement amount of the light having the directivity detected by the curvature correction amount detection system when the curvature of the reflection mirror is corrected corresponds to the calculated strain amount of the workpiece. An exposure apparatus, wherein the curvature is corrected by moving the support mechanism by the driving means. The detection light source irradiates light having the directivity from an exposure surface side toward the reflection mirror from the reflection mirror in the optical path of the light beam of the exposure light,
11. The exposure apparatus according to claim 10, wherein the reflection plate is disposed in the vicinity of the integrator of the illumination optical system so as to be retractable from the optical path of the light beam of the exposure light.

Images