JP2015222417A - Apparatus and method for exposure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for exposure which improve the illuminance distribution of an exposure area of exposure light and thereby increase the exposure accuracy even when the curvature of a reflector is corrected.SOLUTION: An exposure apparatus PE is provided with an illuminometer 40 for measurement of the illuminance of exposure light applied to work W. Before exposure of the work W, the illuminance distribution of the exposure light area A of the exposure light to be applied to the work W through a planar mirror 68 is measured by using the illuminometer 40.

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.

  Conventionally, a mirror element having a reflecting surface that reflects illumination light and a plurality of drive units that deform the reflecting surface by applying a force to the back surface of the mirror element, and the reflecting surface can be deformed into various shapes An exposure apparatus including the above optical system is disclosed (see, for example, Patent Documents 1 and 2). As shown in FIG. 8, in the exposure apparatus of Patent Document 1, a mirror element 101 having a reflection surface 101a that reflects the irradiation light IL, a plurality of drive units 102 arranged on the back surface of the mirror element 101, and the mirror element 101 A holding block 103 that holds the holding portion 101b at the peripheral portion, and the reflective surface 101a of the mirror element 101 is deformed into various shapes by a plurality of drive units 102, and correction is difficult with a normal imaging characteristic correction mechanism. The non-rotationally symmetric aberration component such as astigmatism on the optical axis was corrected.

  In the exposure apparatus of Patent Document 2, the back surface of the plane mirror is supported on the holding frame via a plurality of support members, ball joints, and pads, and the support member is driven by the drive device to cope with the distortion of the workpiece. By correcting the curvature of the mirror, the mask pattern is exposed according to the shape of the exposed area of the workpiece.

JP 2013-161992 A JP 2011-123461 A

  By the way, in the exposure apparatus described in Patent Document 2, when the curvature of the plane mirror is corrected in response to the distortion of the workpiece, the illuminance distribution of the exposure light is deteriorated, and therefore it is required to improve the deterioration of the illuminance distribution. .

  The present invention has been made in view of the above-described problems, and its purpose is to improve the exposure accuracy by improving the illuminance distribution of the exposure area of the exposure light even when the curvature of the reflecting mirror is corrected. It is an object of the present invention to provide an exposure apparatus and an exposure method that can perform the above.

The above object of the present invention can be achieved by the following constitution.
(1) a work support part for supporting the work;
A mask support for supporting the mask;
An illumination optical system having a light source and a reflecting mirror that reflects exposure light from the light source;
A mirror bending mechanism capable of correcting the curvature of the reflecting mirror;
An exposure apparatus that irradiates the work with exposure light from the light source through the mask and transfers the pattern of the mask to the work,
An illuminance meter that measures the illuminance of exposure light irradiated on the workpiece,
An exposure apparatus for measuring an illuminance distribution in an exposure area of the exposure light irradiated onto the work through the reflecting mirror before the work is exposed using the illuminometer.
(2) A feed mechanism for moving the work support portion so as to relatively move the work and the mask in the horizontal direction,
The exposure apparatus according to (1), wherein the illuminance meter is movable across the entire exposure area by driving the feeding mechanism.
(3) The reflection mirror corrects its curvature by driving the mirror bending mechanism according to the illuminance distribution of the exposure area measured by the illuminometer (1) or ( The exposure apparatus according to 2).
(4) The illumination optical system includes a plurality of the reflecting mirrors,
The mirror bending mechanism includes a plurality of mirror bending mechanisms capable of correcting curvatures of the plurality of reflecting mirrors, respectively.
For any one of the plurality of reflecting mirrors, the curvature is corrected by driving the mirror bending mechanism,
The other of the plurality of reflecting mirrors drives the mirror bending mechanism in accordance with the illuminance distribution of the exposure area measured by the illuminance meter with the curvature of any one of the reflecting mirrors corrected. Thus, the curvature is corrected, and the exposure apparatus according to (1) or (2).
(5) An exposure method using the exposure apparatus according to (3), wherein the work is irradiated with exposure light from the light source through the mask and the pattern of the mask is transferred to the work. A step of measuring an illuminance distribution of an exposure area of the exposure light irradiated onto the workpiece through a reflecting mirror using the illuminance meter;
Correcting the curvature of the reflecting mirror by driving the mirror bending mechanism according to the illuminance distribution of the exposure area measured by the illuminometer;
An exposure method comprising:
(6) An exposure method that uses the exposure apparatus according to (4) to irradiate the workpiece with the exposure light from the light source through the mask and transfer the pattern of the mask onto the workpiece. A step of correcting the curvature by driving the mirror bending mechanism with respect to any one of a plurality of reflecting mirrors;
Measuring the illuminance distribution of the exposure area of the exposure light irradiated onto the workpiece through the one reflecting mirror whose curvature is corrected by the mirror bending mechanism, using the illuminometer;
The other of the plurality of reflecting mirrors drives the mirror bending mechanism in accordance with the illuminance distribution of the exposure area measured by the illuminance meter with the curvature of any one of the reflecting mirrors corrected. The process of correcting the curvature,
An exposure method comprising:

  According to the exposure apparatus and the exposure method of the present invention, the illuminance meter that measures the illuminance of the exposure light applied to the workpiece is provided, and before the workpiece is exposed, the reflection is corrected by the mirror bending mechanism. The illuminance distribution in the exposure area of the exposure light irradiated on the workpiece is measured using an illuminometer. Thereby, the illuminance distribution of the exposure area can be obtained, and when the target illuminance distribution is not reached, the mirror bending mechanism of the reflector whose curvature is corrected or another reflector is driven again, and the target By performing fine adjustment so as to reach the illuminance distribution, the illuminance distribution in the exposure area of the exposure light can be improved and the exposure accuracy can be increased.

It is a front view of the exposure apparatus which concerns on this invention. It is a figure which shows the illumination optical system which concerns on 1st Embodiment of this invention. (A) is a top view which shows the reflecting mirror support structure of an illumination optical system, (b) is sectional drawing along the III-III line of (a), (c) is III of (a). It is sectional drawing along line '-III'. (A)-(d) is the schematic explaining the process of measuring the illumination intensity distribution of an exposure area. It is the V section enlarged view of FIG. It is a figure which shows the flowchart of the exposure method of this embodiment. It is a figure which shows the illumination optical system which concerns on 2nd Embodiment of this invention. It is a figure which shows the conventional reflecting mirror support structure.

(First embodiment)
Hereinafter, an embodiment of an exposure apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 shows an exposure apparatus according to the present invention.
As shown in FIG. 1, the proximity exposure apparatus PE uses a mask M smaller than a workpiece W as a material to be exposed, holds the mask M on a mask stage 1, and holds the workpiece W on a workpiece stage (work support unit) 2. The pattern of the mask M is irradiated by irradiating the mask M with light for pattern exposure from the illumination optical system 3 in a state where the mask M and the workpiece W are placed close to each other with a predetermined exposure gap. The exposure is transferred onto the workpiece W. Further, the work stage 2 is moved stepwise relative to the mask M in the two axial directions of the X axis direction and the Y axis direction, and exposure transfer is performed for each step.

  In order to move the work stage 2 stepwise in the X-axis direction, an X-axis stage feed mechanism 5 for moving the X-axis feed base 5a stepwise in the X-axis direction is installed on the apparatus base 4. On the X-axis feed base 5a of the X-axis stage feed mechanism 5, a Y-axis stage feed mechanism 6 for step-moving the Y-axis feed base 6a in the Y-axis direction is installed in order to move the work stage 2 stepwise in the Y-axis direction. Has been. The work stage 2 is installed on the Y-axis feed base 6 a of the Y-axis stage feed mechanism 6. On the upper surface of the work stage 2, the work W is held in a state of being sucked by a work chuck or the like. Further, a substrate side displacement sensor 15 for measuring the lower surface height of the mask M is disposed on the side portion of the work stage 2. Therefore, the substrate side displacement sensor 15 can move in the X and Y axis directions together with the work stage 2.

  On the apparatus base 4, a plurality of (four in the embodiment shown in the figure) X-axis linear guide rails 51 are arranged in the X-axis direction, and each guide rail 51 has a lower surface of the X-axis feed base 5 a. A slider 52 fixed to the bridge is straddled. Thereby, the X-axis feed base 5 a is driven by the first linear motor 20 of the X-axis stage feed mechanism 5 and can reciprocate along the guide rail 51 in the X-axis direction. A plurality of guide rails 53 for Y-axis linear guides are arranged on the X-axis feed base 5a in the Y-axis direction. Each guide rail 53 has a slider 54 fixed to the lower surface of the Y-axis feed base 6a. Is straddled. Accordingly, the Y-axis feed base 6 a is driven by the second linear motor 21 of the Y-axis stage feed mechanism 6 and can reciprocate in the Y-axis direction along the guide rail 53.

  Between the Y-axis stage feed mechanism 6 and the work stage 2, since the work stage 2 is moved in the vertical direction, the vertical coarse motion device 7 having a relatively coarse positioning resolution but a large moving stroke and moving speed, and the vertical coarse motion Positioning with high resolution is possible compared with the apparatus 7, and a vertical fine movement apparatus 8 is provided for finely adjusting the gap between the opposing surfaces of the mask M and the work W to a predetermined amount by finely moving the work stage 2 up and down. .

  The vertical coarse movement device 7 moves the work stage 2 up and down with respect to the fine movement stage 6b by an appropriate drive mechanism provided on the fine movement stage 6b described later. The stage coarse movement shafts 14 fixed at four positions on the bottom surface of the work stage 2 are engaged with linear motion bearings 14a fixed to the fine movement stage 6b, and are guided in the vertical direction with respect to the fine movement stage 6b. In addition, it is desirable that the vertical coarse motion device 7 has high repeated positioning accuracy even if the resolution is low.

  The vertical fine movement device 8 includes a fixed base 9 fixed to the Y-axis feed base 6a, and a linear guide guide rail 10 attached to the fixed base 9 with its inner end inclined obliquely downward. A ball screw nut (not shown) is coupled to a slide body 12 that reciprocates along the guide rail 10 via a slider 11 straddling the guide rail 10, and an upper end surface of the slide body 12. Is in contact with the flange 12a fixed to the fine movement stage 6b so as to be slidable in the horizontal direction.

Then, when the screw shaft of the ball screw is rotationally driven by the motor 17 attached to the fixed base 9, the nut, the slider 11 and the slide body 12 are integrally moved along the guide rail 10 in an oblique direction. The flange 12a is finely moved up and down.
Note that the vertical fine movement device 8 may drive the slide body 12 by a linear motor instead of driving the slide body 12 by the motor 17 and the ball screw.

The vertical fine movement device 8 is installed on one end side (left end side in FIG. 1) in the Y-axis direction of the Z-axis feed base 6a and two on the other end side, for a total of three units, and each is independently driven and controlled. It has become so. Accordingly, the vertical fine movement device 8 independently finely adjusts the heights of the three flanges 12 a based on the measurement results of the gap amounts between the mask M and the workpiece W at a plurality of locations by the gap sensor 27, and the workpiece stage 2. Fine-tune the height and inclination of
In addition, when the height of the work stage 2 can be sufficiently adjusted by the vertical fine movement device 8, the vertical coarse movement device 7 may be omitted.

  On the Y-axis feed base 6a, a bar mirror 19 facing the Y-axis laser interferometer 18 that detects the position of the work stage 2 in the Y direction, and an X-axis laser that detects the position of the work stage 2 in the X-axis direction. A bar mirror (both not shown) facing the interferometer is installed. The bar mirror 19 facing the Y-axis laser interferometer 18 is arranged along the X-axis direction on one side of the Y-axis feed base 6a, and the bar mirror facing the X-axis laser interferometer is located on the Y-axis feed base 6a. It is arranged along the Y-axis direction on one end side.

  The Y-axis laser interferometer 18 and the X-axis laser interferometer are arranged so as to always face the corresponding bar mirrors and supported by the apparatus base 4. Two Y-axis laser interferometers 18 are installed apart from each other in the X-axis direction. The two Y-axis laser interferometers 18 detect the position of the Y-axis feed base 6a and consequently the work stage 2 in the Y-axis direction and the yawing error via the bar mirror 19. In addition, the X-axis laser interferometer detects the position of the X-axis feed base 5a and eventually the work stage 2 in the X-axis direction via the opposing bar mirror.

  The mask stage 1 is inserted in a X, Y, θ direction (in the X, Y plane) by inserting a mask base frame 24 composed of a substantially rectangular frame body and a gap into a central opening of the mask base frame 24. The mask base frame 24 is held at a fixed position above the work stage 2 by a support column 4a protruding from the apparatus base 4.

  A frame-shaped mask holder (mask support portion) 26 is provided on the lower surface of the central opening of the mask frame 25. That is, a plurality of mask holder suction grooves connected to a vacuum suction device (not shown) are provided on the lower surface of the mask frame 25, and the mask holder 26 is sucked to the mask frame 25 through the plurality of mask holder suction grooves. Retained.

  A plurality of mask suction grooves (not shown) are provided on the lower surface of the mask holder 26 for sucking the peripheral portion of the mask M on which the mask pattern is not drawn. The mask M passes through the mask suction grooves. Then, it is detachably held on the lower surface of the mask holder 26 by a vacuum suction device (not shown).

  As shown in FIG. 2, the illumination optical system 3 of the exposure apparatus PE of this embodiment includes, for example, a high-pressure mercury lamp 61 that is a light source for ultraviolet irradiation, and a reflector that collects light emitted from the high-pressure mercury lamp 61. A multi-lamp unit 60 provided with 62, a plane mirror 63 for changing the direction of the optical path EL, an exposure control shutter unit 64 for controlling the opening and closing of the irradiation optical path, and a downstream side of the exposure control shutter unit 64. An optical integrator 65 that emits the light collected by the reflector 62 so as to have as uniform an illuminance distribution as possible in the irradiation region; a plane mirror 66 for changing the direction of the optical path EL emitted from the optical integrator 65; Collimation mirror 67 for irradiating light from high-pressure mercury lamp 61 as parallel light Comprises a plane mirror 68 for irradiating the the parallel light to the mask 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 open during exposure, the light emitted from the multi-lamp unit 60 passes through the plane mirror 63, the optical integrator 65, the plane mirror 66, the collimation mirror 67, and the plane mirror 68. Then, the mask M held by the mask holder 26 and, consequently, the surface of the work W are irradiated as light for pattern exposure, and the exposure pattern of the mask M is exposed and transferred onto the work W.

  Here, as shown in FIG. 3, the plane mirror 68 is made of a glass material formed in a rectangular shape in front view. The plane mirror 68 is supported on the mirror deformation unit holding frame 71 by a plurality of mirror deformation units (mirror bending mechanisms) 70 provided on the back side of the plane mirror 68.

  Each mirror deformation unit 70 includes a pad 72 that is fixed to the back surface of the flat mirror 68 with an adhesive, a support member 73 that is fixed to the pad 72 at one end, and an actuator 74 that is a drive device that drives the support member 73. Is provided.

  The support member 73 is provided with a ball joint 76 as a bending mechanism that allows bending of ± 0 · 5 deg or more at a position close to the pad 72 with respect to the holding frame 71, and is opposite to the holding frame 71. An actuator 74 is attached to the other end.

  Further, a plurality of contact sensors 81 are attached to the back surface of each position of the flat mirror 68 that reflects the exposure light at the position of an alignment mark (not shown) on the mask side.

  Thereby, the plane mirror 68 drives the actuator 74 of each mirror deformation | transformation unit 70, sensing the displacement amount of the plane mirror 68 with the contact-type sensor 81, and changes the length of each support member 73, and thereby the plane mirror 68 The curvature of the mirror 68 can be locally corrected, and the declination angle of the plane mirror 68 can be corrected.

  At this time, each mirror deformation unit 70 is provided with a ball joint 76, so that the portion on the support side can be rotated three-dimensionally, and each pad 72 is placed on the surface of the plane mirror 68. Can be tilted along. For this reason, the adhesive peeling between each pad 72 and the plane mirror 68 is prevented, and the stress of the plane mirror 68 between the pads 72 having different movement amounts is suppressed, and the average fracture stress value is made of a small glass material. Even when the curvature of the plane mirror 68 is locally corrected, the plane mirror 68 can be bent on the order of 10 mm without damaging the plane mirror 68, and the curvature can be greatly changed.

  Returning to FIG. 2, in this embodiment, when the curvature of the plane mirror 68 is corrected, the curvature correction of the plane mirror 68 is appropriately performed with respect to the target displacement amount corresponding to the strain amount of the workpiece W and the target illuminance distribution. A curvature correction amount detection system 90 is provided for determining whether or not it has been broken. The curvature correction amount detection system 90 irradiates laser light L as light having directivity from the exposure surface side (in the vicinity of the mask in this embodiment) toward the plane mirror 68 from the plane mirror 68 in the optical path EL of the light beam of exposure light. A plurality of (four in the present embodiment) laser pointers 91, a reflector 92 disposed in the vicinity of the optical integrator 65 so as to be retractable from the optical path EL of the light beam of exposure light, and a plane mirror 68 Are provided between the camera 93 and an actuator 74 of the mirror deformation unit 70 of the plane mirror 68 as an imaging means for imaging the laser light L reflected on the reflection plate 92. The amount of displacement of the laser beam L imaged when the curvature is corrected is detected, and the mirror deformation unit is set so that the amount of displacement corresponds to the target amount of displacement. And a control unit 94 for controlling the actuator 74 of the bets 70.

  The laser pointer 91 is attached to, for example, an upper part of a CCD camera (not shown) for detecting alignment, and moves in synchronization with the CCD camera moving forward and backward to a position where the alignment mark on the mask side can be visually recognized.

  Since the reflecting plate 92 is disposed 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 68, the collimation mirror 67, and the plane mirror 66. 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 mask M is 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 a displacement amount before and after the curvature correction, and confirms whether the displacement amount corresponds to the target displacement amount. Thus, a control signal is given to the actuator 74 of the mirror deformation unit 70 of the plane mirror 68.

  As shown in FIG. 1, an illuminance meter 40 that measures the illuminance of exposure light applied to the work W is attached to the side of the work stage 2, and the X-axis stage feed mechanism 5 and the Y-axis stage are attached. The feed mechanism 6 moves in the horizontal direction as the work stage 2 moves.

  Specifically, as shown in FIGS. 4A to 4D, the illuminance is such that the illuminance meter 40 moves to each vertex of a quadrangle obtained by dividing the exposure area A of the exposure light irradiated onto the workpiece W into 16 squares. The illuminance distribution of the entire exposure area is obtained by moving the total 40 together with the work stage 2 and measuring the illuminance at each vertex by the illuminance meter 40.

As shown in FIG. 5, a drive mechanism 42 that drives a blind (shutter) 41 that can advance and retreat above the illuminometer 40 is provided on the side of the illuminometer 40. Thereby, except at the time of illumination intensity measurement, deterioration of the illumination meter 40 by exposure light can be suppressed by shielding the illumination meter 40 from exposure light by the blind 41.
In addition, the illuminometer 40 performs zero point adjustment by blocking light to the illuminometer 40 by the blind 41 before starting the illuminance measurement.

Next, the exposure method of this embodiment is demonstrated with reference to the flowchart shown in FIG.
First, the workpiece W is transported to the exposure position and irradiated with exposure light (step S1). Next, the illuminance meter 40 measures the illuminance distribution of the entire exposure area A (step S3). Here, the mirrors 66, 67, and 68 in the initial state are likely to slightly vary in reflectance and curvature, and in this case, the illuminance distribution of the exposure light reflected by the mirrors 66, 67, and 68 also varies. Arise.

  For this reason, the measured illuminance distribution is compared with the target illuminance distribution (step S4). If the measured illuminance distribution reaches the target illuminance distribution in step S4, actual exposure is started (step S5). On the other hand, if the measured illuminance distribution does not reach the target illuminance distribution, a difference calculation is performed (step S6).

  Next, in step S7, the actuator 74 of each mirror deformation unit 70 is driven and controlled based on the difference calculation, and the amount of displacement of the plane mirror 68 is confirmed by the contact sensor 81 and the curvature correction amount detection system 90. The curvature of 68 is corrected.

  Thereafter, steps S3 to S7 are repeated until the measured illuminance distribution reaches the target illuminance distribution. As a result, it is possible to improve the exposure accuracy by improving the illuminance distribution of the exposure area of the exposure light.

  The correction of the illuminance distribution is performed every time the mirror bending offset amount changes. Furthermore, since the offset amount of mirror bending differs for 4 to 8 shots per workpiece, the illuminance distribution is corrected each time the offset amount is changed.

  In step S3, the curvature of the plane mirror 68 may be corrected for the first time before measuring the illuminance distribution (step S2 ′). In this case, the drive amount of the actuator 74 is based on the amount of deviation between the alignment marks Wa and Ma detected by each CCD camera 30 when the alignment mark of the workpiece W and the alignment mark of the mask M are detected by the plurality of CCD cameras 30. Thus, the amount of positional deviation between the center of the mask M and the center of the workpiece W and the strain amount of the workpiece W may be calculated separately and determined according to the strain amount of the workpiece W. In this case, the amount of positional deviation between the center of the mask M and the center of the workpiece W is performed by driving and controlling the alignment mechanism on the mask M side. In this case, the curvature correction of the flat mirror 68 based on the difference calculation in step S7 is performed so that the corrected strain amount of the workpiece W is within the allowable range.

  Alternatively, the first curvature correction of the plane mirror 68 in step S2 ′ is performed by setting the drive amount of the actuator 74 so as to preliminarily adjust apparatus-specific errors in the illumination optical system 3 and the exposure apparatus. May be.

  As described above, according to the exposure apparatus PE of the present embodiment, the illuminance meter 40 that measures the illuminance of the exposure light irradiated on the workpiece W is provided, and before the workpiece W is exposed, the exposure device PE passes through the plane mirror 68. The illuminance distribution in the exposure area A of the exposure light irradiated on the workpiece W is measured using the illuminometer 40. Thereby, the illuminance distribution of the exposure area A can be acquired, and when the target illuminance distribution is not reached, the mirror deformation unit 70 of the plane mirror 68 whose curvature is corrected is driven again to reach the target illuminance distribution. By performing the fine adjustment up to the above, it is possible to improve the exposure accuracy by improving the illuminance distribution of the exposure area A of the exposure light.

Further, the exposure apparatus includes an X-axis stage feed mechanism 5 and a Y-axis stage feed mechanism 6 that move the work stage 2 so as to relatively move the work W and the mask M in the horizontal direction. These feeding mechanisms 5 and 6 are driven so that the entire exposure area A can be moved. Thereby, the illuminance of the whole exposure area A can be measured by reducing the number of illuminance meters 40.
In the present invention, the number of illuminance meters 40 may be plural, and the illuminance at each position in the exposure area A may be measured simultaneously by the plural illuminance meters 40 to shorten the measurement time. .

  Further, according to the exposure method of the present embodiment, the mirror deformation unit 70 measures the illuminance distribution in the exposure area A of the exposure light irradiated onto the workpiece W via the plane mirror 68 using the illuminometer 40. And a step of correcting the curvature of the plane mirror 68 by driving the mirror deformation unit 70 in accordance with the illuminance distribution of the exposure area A measured by the illuminometer 40. Thereby, the illuminance distribution of the exposure area A can be acquired, and when the target illuminance distribution is not reached, the mirror deformation unit 70 of the plane mirror 68 whose curvature is corrected is driven again to reach the target illuminance distribution. By performing the fine adjustment up to the above, it is possible to improve the exposure accuracy by improving the illuminance distribution of the exposure area A of the exposure light.

(Second Embodiment)
Next, an exposure apparatus according to the second embodiment of the present invention will be described with reference to FIG. Since the illumination optical system 3 of the present embodiment has the same configuration as the illumination optical system of the first embodiment, the same or equivalent parts as those of the first embodiment are denoted by the same reference numerals in the drawings and the description thereof is made. Is omitted or simplified.

  In the illumination optical system 3 of the present embodiment, as shown in FIG. 7, the mirror deformation unit 70 is also attached to the back side of the plane mirror 68 and the back side of the other plane mirror 66. The curvature of the plane mirror 66 can be corrected locally.

  In other words, in the first embodiment, the deterioration of the illuminance distribution due to variations in the reflectivity and curvature of each of the plurality of mirrors 66, 67, 68 is suppressed by the curvature correction of one plane mirror 68. However, if the deterioration of the illuminance distribution is suppressed by correcting the curvature of the plurality of mirrors 66 and 68 as in the present embodiment, a desired curvature can be obtained for each of the mirrors 66 and 68, more easily. The illuminance distribution can be improved.

  In the flowchart of FIG. 6 of the first embodiment, the curvature correction of the mirrors 66 and 68 in step S7 may be performed by both the mirrors 66 and 68, or one of the mirrors 66 and 68. The curvature correction may be appropriately performed.

  For example, the curvature is corrected by driving the mirror deformation unit 70 with respect to the plane mirror 68 in step S7, and the workpiece W is irradiated through the plane mirror 68 in step S3 of the next step. The illuminance distribution in the exposure area A of the exposure light is measured using the illuminometer 40. If the target illuminance distribution is not reached in step S4, a difference calculation is performed in step S6, and in the next step S7, The other flat mirror 66 corrects the curvature by driving the mirror deformation unit 70 according to the illuminance distribution of the exposure area A measured by the illuminometer 40 in a state where the curvature of the flat mirror 68 is corrected. . As a result, the illuminance distribution in the exposure area A can be acquired. If the target illuminance distribution is not reached, the mirror deformation unit 70 of the other plane mirror 66 is driven and fine adjustment is performed until the target illuminance distribution is reached. By performing the above, it is possible to improve the exposure accuracy by improving the illuminance distribution of the exposure area A of the exposure light.

Accordingly, also in the illumination optical system 3 of the present embodiment having the above-described configuration, the curvature of the plane mirror 68 and the other plane mirror 66 is locally corrected, thereby reducing the declination angle of the exposure light. It can be changed and the illuminance distribution can be improved.
The mirror deformation unit 70 may also be attached to the back side of the collimation mirror 67.
About another structure and an effect, it is the same as that of the said 1st Embodiment.

  As a modification of the present embodiment, for example, when the workpiece W is distorted, the mask M is corrected by correcting the curvature with the mirror deformation unit 70 of the plane mirror 68 according to the shape of the exposed region of the workpiece W. The deterioration of the illuminance distribution of the exposure light caused by the exposure transfer of the pattern with high accuracy and the correction of the curvature by the mirror deformation unit 70 of the plane mirror 68 is performed by changing the curvature of the other plane mirror 66. May be suppressed by changing the illuminance and exposure at a high resolution may be performed by improving the illuminance distribution.

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

1 Mask stage (mask support part)
2 Work stage (work support part)
3 Illumination optical system 5 X-axis stage feed mechanism 6 Y-axis stage feed mechanism 40 Illuminance meter 60 Multi lamp unit (light source)
65 Optical integrator 66, 68 Plane mirror (reflector with mirror bending mechanism)
70 Mirror deformation unit (mirror bending mechanism)
EL Optical path M Mask PE Exposure device W Workpiece

Claims (6)

A workpiece support section for supporting the workpiece;
A mask support for supporting the mask;
An illumination optical system having a light source and a reflecting mirror that reflects exposure light from the light source;
A mirror bending mechanism capable of correcting the curvature of the reflecting mirror;
An exposure apparatus that irradiates the work with exposure light from the light source through the mask and transfers the pattern of the mask to the work,
An illuminance meter that measures the illuminance of exposure light irradiated on the workpiece,
An exposure apparatus for measuring an illuminance distribution in an exposure area of the exposure light irradiated onto the work through the reflecting mirror before the work is exposed using the illuminometer. A feed mechanism for moving the work support so as to move the work and the mask in a horizontal direction relative to each other;
The exposure apparatus according to claim 1, wherein the illuminance meter is movable across the entire exposure area by driving the feeding mechanism.   The said reflecting mirror correct | amends the curvature by driving the said mirror bending mechanism according to the illumination intensity distribution of the said exposure area measured by the said illumination meter. Exposure device. The illumination optical system includes a plurality of the reflecting mirrors,
The mirror bending mechanism includes a plurality of mirror bending mechanisms capable of correcting curvatures of the plurality of reflecting mirrors, respectively.
For any one of the plurality of reflecting mirrors, the curvature is corrected by driving the mirror bending mechanism,
The other of the plurality of reflecting mirrors drives the mirror bending mechanism in accordance with the illuminance distribution of the exposure area measured by the illuminance meter with the curvature of any one of the reflecting mirrors corrected. The exposure apparatus according to claim 1, wherein the curvature is corrected. An exposure method using the exposure apparatus according to claim 3, wherein the work is irradiated with exposure light from the light source through the mask and the pattern of the mask is transferred to the work.
A step of measuring an illuminance distribution of an exposure area of the exposure light irradiated onto the workpiece through the reflecting mirror using the illuminance meter;
Correcting the curvature of the reflecting mirror by driving the mirror bending mechanism according to the illuminance distribution of the exposure area measured by the illuminometer;
An exposure method comprising: An exposure method that uses the exposure apparatus according to claim 4 to irradiate the workpiece with the exposure light from the light source through the mask and transfer the pattern of the mask onto the workpiece.
A step of correcting the curvature by driving the mirror bending mechanism with respect to any one of the plurality of reflecting mirrors;
Measuring the illuminance distribution of the exposure area of the exposure light irradiated onto the workpiece through the one reflecting mirror whose curvature is corrected by the mirror bending mechanism, using the illuminometer;
The other of the plurality of reflecting mirrors drives the mirror bending mechanism in accordance with the illuminance distribution of the exposure area measured by the illuminance meter with the curvature of any one of the reflecting mirrors corrected. The process of correcting the curvature,
An exposure method comprising:

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