JPH0855784A - Aligner - Google Patents

Abstract

PURPOSE:To properly correct image formation property by measuring the quantity of slippage of the image by the projective optical systems corresponding to each of reference marks and the reference marks, and correcting the image formation property of a plurality of projective optical systems, according to the quantity of slippage. CONSTITUTION:The quantity of slippage between the image by a plurality of projective optical systems 5-9 corresponding to each of the first reference mark 10A on the side of a mask face and the second reference mark 10B on the side of a mask face, the first reference mark 11 on the side of a photosensitive substrate and the second reference mark 11 on the side of the photosensitive substrate or the quantity of slippage between the image by a plurality of projective optical systems 5-9 corresponding to each of the first reference mark 11 on the side of the photosensitive substrate and the second reference mark 11 on the side of the photosensitive substrate and the first reference mark 10A on the side of the mark face and the second reference mark 10B on the side of the mask face is measured, and the image formation property of the projective optical systems 5-9 is corrected, according to the quantity of its slippage. Hereby, the projective optical systems 5-9 can be optimized by directly measuring the quantity of slippage being obtained by projecting it actually, so the image formation property of the projecting optical systems 5-9 can be properly corrected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus, and more particularly, it can be applied to an exposure apparatus for manufacturing a semiconductor element or a liquid crystal display substrate, which has a plurality of projection optical systems.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display substrate has been widely used as a display element of a personal computer or a television receiver. This liquid crystal display substrate is manufactured by patterning a transparent thin film electrode on a glass substrate into a desired shape by a photolithographic method. As an apparatus for this lithography, a projection exposure apparatus is used which exposes an original image pattern formed on a mask onto a photoresist layer on a glass substrate via a projection optical system.

Recently, there has been a demand for a larger area of the liquid crystal display substrate, and accordingly, the projection exposure apparatus is also required to expand the exposure area. As a means for enlarging the exposure area, a scanning type exposure apparatus having a plurality of projection lenses can be considered. That is, in this scanning exposure apparatus, after the light flux emitted from the light source is made uniform in the amount of light through an optical system including a fly-eye lens and the like, it is shaped into a desired shape by a field stop and the pattern surface of the mask is formed. Illuminate.

A plurality of illumination systems having such a configuration are arranged, and different small areas (illumination areas) on the mask are illuminated by the light beams emitted from each of the plurality of illumination systems. The light flux that has passed through the mask forms a pattern image of the mask on different projection regions on the glass substrate through a plurality of different projection lenses. Then, by synchronously scanning the mask and the glass substrate with respect to the projection lens, the entire surface of the pattern area on the mask is transferred onto the glass substrate.

[0005]

By the way, in the scanning type exposure apparatus having the above-mentioned structure, the continuous pattern of the mask is divided by a plurality of projection lenses so that the divided images are not overlapped or overlapped by a predetermined amount on the glass substrate. Therefore, if there is a large difference in the image forming characteristics of the projection lenses, there arises a problem that divided images are not continuously formed on the glass substrate.

Therefore, when assembling a plurality of projection lenses, adjustment is made so as to minimize the difference in image forming characteristics, but there is a problem that the work is difficult and time is required. In addition, even after being assembled once, the imaging characteristics may change with time, which is not practically sufficient.

The present invention has been made in consideration of the above points, and the mask and the photosensitive substrate are synchronously scanned with respect to a plurality of projection optical systems so that the entire surface of the pattern area on the mask is correctly exposed on the photosensitive substrate. The present invention is intended to propose an exposure device capable of transferring to the.

[0008]

In order to solve such a problem, according to the present invention, a plurality of illumination optical systems (3) for irradiating a plurality of partial areas in a pattern area of a mask (2) with a light flux of a light source, The images of the plurality of partial regions are arranged along a predetermined direction and displaced from each other in a direction orthogonal to the predetermined direction, and the images of the plurality of partial regions are overlapped with each other in the positions of the adjacent images in the predetermined direction. A plurality of projection optical systems (5-9) for projecting onto the photosensitive substrate (4), and a direction (a) substantially orthogonal to a predetermined direction with respect to the projection optical systems (5-9).
And a scanning means for scanning the mask (2) and the photosensitive substrate (4) in synchronization with each other, and the mask (2) and the photosensitive substrate (4).
In the exposure device (1) for transferring the entire pattern area of the mask (2) onto the photosensitive substrate (4) by scanning and with respect to the projection optical system (5 to 9), on the mask (2) surface. And at positions corresponding to each other on the photosensitive substrate surface (4) and at positions conjugate with the projection optical systems (5, 7) at both ends of the array of the plurality of projection optical systems (5-9). 2 sets of mask surface side first fiducial marks (10A
(A, b)) and the first reference mark (11
(A ', b')) and a position corresponding to each other on the mask (2) surface and the photosensitive substrate surface (4) and corresponding to overlapping positions are arranged in one row in a predetermined direction and Are fixed with respect to the mask surface side first reference mark (10A (a, b)) and the photosensitive substrate surface side first reference mark (11 (a ', b')), and the other is movable. Side second reference mark (10B (c to h)) and photosensitive substrate surface side second reference mark (11 (c 'to h')), mask surface side first reference mark (10A (a, b)) and Images of the mask surface side second reference marks (10B (c to h)) by the corresponding plurality of projection optical systems (5 to 9) and the photosensitive substrate side first reference marks (11 (a ', b')). ) And the second reference mark (11 (c'-h ')) on the photosensitive substrate side, or the first reference mark ( 1 (a ', b')) and the second reference mark (11 (c'-h ')) on the photosensitive substrate side by the corresponding plurality of projection optical systems (5-9) and the mask surface side first image. Deviation amount measuring means (12 to 16, 23, 24) for measuring the amount of deviation between the first reference mark (10A (a, b)) and the mask surface side second reference mark (10B (c to h)).
And a plurality of projection optical systems (5 to 5) according to the deviation amount measured by the deviation amount measuring means (12 to 16, 23, 24).
9) Lens adjusting means (1) for correcting each image forming characteristic
7 to 21).

In the present invention, the mask-side first reference mark (10A (a, b)) and the photosensitive-substrate-side first reference mark (11 (a ', b')) are the mask (2) surface. It is arranged integrally with the block (22) having sufficient rigidity to hold it on the top and the corresponding surface of the photosensitive substrate (4).

Further, according to the present invention, the mask surface side first reference mark (10A) is provided by the shift amount measuring means (23, 24).
(A, b)) and the first reference mark (11
(A ′, b ′)), the projection optical system (5,
As a correction value that minimizes the distortion of each projected image due to 7), a value for adjusting at least one of the projection magnification of the projection optical system (5, 7), the rotation of the projected image, and the shift is obtained, and the lens adjustment means According to (17, 19), the imaging characteristics are changed by changing at least one of the magnification of the projection optical system (5, 7) at both ends, the rotation of the projected image, and the shift according to the correction value. Modified projection optics on both ends (5, 7)
2nd fiducial mark (10B
(C to h)) or an image of the second reference mark on the photosensitive substrate surface side,
The second reference mark (11 (c '...
h ')) or the mask surface side second reference mark (10B (c to h)) or the photosensitive substrate surface side first reference mark are moved and positioned so as to match the mask surface side second reference mark,
The displacement amount measuring means (12 to 16) uses a plurality of mask surface side second reference marks (10B (c to h)) and a photosensitive substrate surface side second reference mark (11 (c 'to h')). At least one of the projection magnification, the rotation and the shift of the projection image of the projection optical system (5-9) is adjusted as a correction value that minimizes the distortion of each projection image by the projection optical system (5-9). A value is obtained, and at least one of the magnification, the rotation and the shift of the projected image of the plurality of projection optical systems (5 to 9) corresponding to the correction value is changed by the lens adjusting means (17 to 21). Then, the image forming characteristic is corrected.

[0011]

A plurality of projection optical systems (5-9) at positions corresponding to each other on the mask (2) surface and the photosensitive substrate surface (4).
Of the two sets of mask surface side first fiducial marks (10A) at positions conjugate with the projection optical system (5, 7) at both ends of the arrangement.
(A, b)) and the first reference mark (11
(A ', b') are respectively arranged, and at a position corresponding to each other on the mask (2) surface and the photosensitive substrate surface (4), and in a predetermined direction corresponding to the overlapping position, and One is the first fiducial mark (10A (a,
b)) and the first reference mark (11 (a ',
b ')), a plurality of mask surface side second reference marks (10B (c to h)) fixed and the other movable, and a photosensitive substrate surface side second reference mark (11 (c' to h ')). ) Are arranged, and the plurality of projection optical systems (5 to 9) corresponding to the mask-side first reference mark (10A (a, b)) and the mask-side second reference mark (10B (c to h)), respectively. Image and the first reference mark (11 (a ', b')) on the photosensitive substrate side
And the second reference mark (11 (c'-h ')) on the photosensitive substrate side
Or the first reference mark (11
(A ', b')) and the second reference mark (11) on the photosensitive substrate side.
(C ′ to h ′)) corresponding images by the plurality of projection optical systems (5 to 9) and the first reference mark (1) on the mask surface side.
0A (a, b)) and the mask surface side second fiducial mark (10
B (c to h)) is measured, and the imaging characteristics of each of the plurality of projection optical systems (5 to 9) are corrected according to the amount of deviation. This makes it possible to directly measure the shift amount obtained by actually projecting and optimize the projection optical system (5 to 9), and to appropriately correct the imaging characteristics of the projection optical system (5 to 9). .

Further, the first reference mark (10A
(A, b)) and the first reference mark (11
(A ', b')) is integrally arranged on the block (22) having sufficient rigidity to hold the mask (2) surface and the photosensitive substrate surface (4) at corresponding positions. , The mask surface side first reference mark (10A (a, b)) and the photosensitive substrate surface side first reference mark (11 (a ', b'))
Can always be kept constant, and the best correction can be performed again even if the imaging characteristics of the projection optical system (5 to 9) change with time due to changes in the environment.

Further, the first reference mark (10A
(A, b)) and the first reference mark (11
(A ′, b ′)), the projection optical system (5,
As a correction value that minimizes the distortion of each projected image due to 7), a value that adjusts at least one of the projection magnification of the projection optical system (5, 7), the rotation of the projected image, and the shift is obtained to form the imaging characteristics. And the image of the mask surface side second fiducial mark (10B (c to h)) or the photosensitive substrate surface side second fiducial mark movable by the projection optical systems (5, 7) at the both ends thus changed, The second reference mark (1
1 (c ′ to h ′)) or the mask surface side second reference mark (10B (c)
~ H)) or the photosensitive substrate surface side second reference mark is moved and positioned, and the mask surface side second reference mark (10B (c ~
h)) and the second reference mark (11 (c '...
h ′)) is used as a correction value for minimizing the distortion of each projection image by the plurality of projection optical systems (5-9), the projection magnification of the projection optical system (5-9), the rotation of the projection image,
Since the value for adjusting at least one of the shifts is obtained to correct the imaging characteristic, the projection optical system (5
To 9) for correcting the mask surface side second reference mark (1
0B (c to h)) and the second reference mark (1
1 (c'-h ')) can be calibrated correctly, thus mask (2) for a plurality of projection optical systems (5-9).
And the photosensitive substrate (4) are synchronously scanned so that the entire surface of the pattern area on the mask (2) is correctly exposed.
Can be transcribed on. The first reference mark (10
A (a, b)) and the first reference mark (11
The accuracy of mounting (a ′, b ′)) on the block (22) is rough and good, and the manufacturing becomes easier accordingly.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a scanning type exposure apparatus which is an erect image as a whole and which has a magnifying power of 1. This exposure apparatus 1
Is composed of an illumination system 3 for irradiating a light flux onto the mask 2 and projection lenses 5 to 9 for projecting the pattern on the mask 2 onto the photosensitive substrate 4. For the illumination system 3 and the projection lenses 5 to 9,
By scanning the mask 2 and the photosensitive substrate 4 synchronously in the direction of the arrow a0, the entire surface of the pattern area on the mask 2 can be transferred onto the photosensitive substrate 4. Further, in this exposure apparatus 1, since the patterns projected on the photosensitive substrate 4 through the projection lenses 5 to 9 are measured, the measuring instruments 12 to 16 are arranged at corresponding positions.

The projection lenses 5-9 include measuring instruments 12-16.
Lens adjustment mechanisms 17 to 21 for adjusting the image forming characteristics of the projection lenses 5 to 9 are installed in order to adjust the amount of deviation of each image measured in step S6. Further, the illumination system 3, the projection lens 5, and the measuring device 12 are arranged in a straight line along the optical axis,
The illumination optical system 3, the projection lenses 6 to 9 and the measuring instruments 13 to 16 are also arranged in the same manner. At this time, projection lenses 5-9
Are arranged in two rows of the projection lenses 5, 6, 7 and the projection lenses 8, 9 and are arranged in a staggered manner so that the exposure images of the adjacent patterns overlap by a predetermined amount. Therefore, the pattern on the mask 2 is divided by the projection lenses 5 to 9 and imaged on the photosensitive substrate 4 at a ratio of 1: 1.

On one side of the mask 2 and the photosensitive substrate 4 in the scanning direction, a mask side reference mark 10 arranged on the same surface as the mask 2 and a photosensitive substrate side reference mark 11 arranged on the same surface as the photosensitive substrate 4. U-shaped block 22 each having
Is provided on the carriage (not shown) for scanning exposure together with the mask 2 and the photosensitive substrate 4. In the exposure apparatus 1, the image forming characteristics (for example, distortion) of the projection lenses 5 to 9 can be measured by using the mask side reference mark 10 and the photosensitive substrate side reference mark 11.

In the case of this embodiment, the mask side reference mark 1
0 and the reference mark 11 on the photosensitive substrate side, the reference mark 11 on the photosensitive substrate side and the fixed mark 1 on the mask side on the block 22.
0A is attached, and the mask side movable mark 10B is attached to the mask stage 2A on which the mask 2 is placed. The mask stage 2A, the photosensitive substrate holder 4A on which the photosensitive substrate 4 is placed, and the block 22 are attached to a carriage, and they are integrated into one body to form the illumination system 3 and the projection lenses 5 to 9.
Move against.

On the mask stage 2A, X, Y, and X are attached to the block 22 and the photosensitive substrate holder 4A on the carriage.
A moving mechanism (not shown) is attached so as to move in the θ direction, and a laser interferometer (not shown) is provided so that its position with respect to the photosensitive substrate holder 4A can be monitored. Further, between the outermost projection lenses 5 and 7 and the illumination system 3, an alignment mark formed on the mask 2 by the projection lenses 5 and 7 and an alignment mark on the mask 2 are formed. Alignment microscopes 23 and 24 for measuring the amount of deviation are installed. The alignment microscopes 23 and 24 are selected in a relatively wide field of view, and also serve as an observation system when the mask side reference mark 10 and the photosensitive substrate side reference mark 11 are calibrated.

The mask side reference mark 10 and the photosensitive substrate side reference mark 11 are shown in FIG. Of the mask side reference mark 10 (FIG. 2A), the mask side fixed mark 10A fixed to the block 22 has at least one or more measurement marks a for each exposure area of the outermost projection lenses 5 and 7. b is included. The movable mark 10 on the mask side
B is formed such that at least two or more measurement marks c to h are included in the exposure areas of the projection lenses 5 to 9. On the other hand, the photosensitive substrate side reference mark 11 paired with the mask side reference mark 10 is the mask side fixed mark 10A.
And both measurement marks a to h of the movable mark 10B on the mask side
One measurement mark a ′ to h ′ corresponding to
Are accurately formed.

In the above structure, first, FIGS. 3 and 4 show the calibration of the projection lenses 5 and 7 located outside by the photosensitive substrate side reference mark 11 and the mask side fixed mark 10A. The carriage is attached to the projection lenses 5 and 7, and the measurement mark a of the mask side fixed mark 10A and the photosensitive substrate side reference mark 11
Of the measurement mark a ′ is moved to a conjugate position, the measurement mark a ′ is projected onto the measurement mark a by the projection lens 5, and as shown in FIG.
The deviation amounts Δx ₁ and Δy ₁ between the projected image and the measurement mark a are measured by. The deviation amounts Δx ₁ and Δy ₁ are shown in FIG.
As shown in, the lens adjustment mechanism 17 of the projection lens 5 moves the image of the measurement mark a ′ so as to shift the image so that it becomes zero. Similarly, alignment microscope 2
The projection optical system 7 is adjusted with reference numeral 4 and the measurement marks b and b '.

Next, as shown in FIGS. 5 and 6, the mask side movable mark 10B is calibrated. That is, the carriage is attached to the projection lens 5 with the measurement mark c of the movable mark 10B on the mask side and the reference mark 11 on the photosensitive substrate side.
The measurement mark c ′ of 1 moves to a position where it becomes conjugate. At this time, the carriage is moved so that the measurement mark h of the mask side movable mark 10B and the measurement mark h ′ of the photosensitive substrate side reference mark 11 are conjugated with respect to the projection lens 7. At this time, the measurement mark a and the measurement mark c are attached to the projection lens 5.
Is preferably at the same position or a position close to each other in the Y direction of FIG. The same applies to the measurement mark b and the measurement mark h.

Then, the measurement mark c'is projected onto the measurement mark c by the projection lens 5 already adjusted by the measurement mark a, and the alignment microscope 23 measures the deviation amounts Δx ₂ and Δy ₂ between the projected image and the measurement mark c. . Similarly, the deviation amounts Δx ₃ and Δy ₃ between the measurement marks h and h ′ are measured, and the mask stage 2A is moved in the X, Y, and θ directions so that the deviation amounts Δx ₂ , Δy ₂ , Δx ₃ , and Δy ₃ become smaller. Moving.

By moving the mask stage 2A in this manner, as shown in FIG. 6A, the amount of deviation between the measurement marks c, c'and h, h'is eliminated. However, when the mask side fixing mark 10A and the photosensitive substrate side reference mark 11 are attached to the block 22 with an error with respect to the design value (that is, in this case, the mask side fixing mark 10A and the photosensitive substrate side reference mark 11 are two-dimensionally). Even if they coincide with each other, the image of the mask-side fixed mark 10A or the photosensitive substrate-side reference mark 11 and the image of the mask-side fixed mark 10A or the photosensitive substrate-side reference mark 11 are obtained through the projection optical system (of the best imaging characteristic). However, the error is included in the position of the mask side movable mark 10B as it is. Therefore, if there is an error, the error amounts αx and αy of the photosensitive substrate side reference mark 11 with respect to the mask side reference mark 10A are measured in advance, and when the mask stage 2A is moved, as shown in FIG. The error amounts αx and αy are added.

In this way, the calibration of the mask side movable mark 10B serving as a reference is completed, and then the steps shown in FIGS.
As shown in (B), the projection lenses 5 to 9 are calibrated. At this time, not only the projection lenses 6, 8 and 9 but also the projection lenses 5 and 7 on the outer side, the respective measurement marks c to h of the calibrated mask side movable mark 10B and the respective measurement marks of the photosensitive substrate side reference mark 11 are calibrated. The deviation amount between c ′ and h ′ is measured by the measuring devices 12 to 16, and the calibration is performed based on the deviation amount obtained by the measurement result.

According to the above construction, before the projection lenses 5 to 9 are calibrated, the respective measurement marks c'to h'of the reference mark 11 on the photosensitive substrate side and the movable mark 11B on the mask side are calibrated.
By calibrating the positions of the measurement marks c to h, the projection lenses 5 to 9 can be calibrated with high accuracy, and thus the mask 2 can be used for the plurality of projection lenses 5 to 9.
Also, the photosensitive substrate 4 can be synchronously scanned to properly transfer the entire surface of the pattern region on the mask 2 onto the photosensitive substrate 4.
Further, according to the above-described configuration, the accuracy of attaching the photosensitive substrate-side reference mark 11 and the mask-side fixed mark 10A to the block 22 and the attachment accuracy of the mask-side movable mark 10B to the mask stage 2A are rough and good. Will be easier.

In the above embodiment, the error amounts αx and αy between the measurement marks a and b of the mask side fixed mark 10A and the measurement marks a ′ and b ′ of the photosensitive substrate side reference mark 11 are used.
However, instead of this, the calibration is performed by setting the error amounts αx and αy to 0 in advance, and finally, the error amount α is set as an offset by exposure.
Even if x and αy are obtained, the same effect as that of the above-described embodiment can be realized.

In the above embodiment, the alignment microscopes 23 and 24 are used to calibrate the photosensitive substrate side reference mark 11 and the mask side movable mark 10B, and a dedicated measuring instrument is used to calibrate the projection lenses 5 to 9. Although the case where 12 to 16 are used has been described, a sensor that serves both may be used. In this case, if a sensor having a mechanism for switching the observation system to a wide field of view or switching the resolution to high is used, the same effect as that of the above-described embodiment can be realized.

Further, in the above-mentioned embodiments, the case where the present invention is applied to the scanning type exposure apparatus in which five projection lenses are arranged is described, but the number of projection lenses may be any number,
Further, since the image of the mask surface may be formed on the surface of the photosensitive substrate as the projection lens, a projection optical system using a reflection mirror may be used. Further, even if the projection optical system is a reduction or enlargement system, the same effect as that of the above-described embodiment can be realized.

[0030]

As described above, according to the present invention, two sets of mask surface side first fiducial marks are provided at positions corresponding to each other on the mask surface and the photosensitive substrate surface and conjugate to the projection optical system at both ends. While arranging the first reference marks on the photosensitive substrate surface side,
One row in a predetermined direction at a position corresponding to and overlapping each other on the mask surface and the photosensitive substrate surface, and one of them is fixed to the mask surface side first reference mark and the photosensitive substrate surface side first reference mark. , A plurality of mask surface side second reference marks and a photosensitive substrate surface side second reference mark, the other of which is movable, and images of a plurality of projection optical systems corresponding to the respective reference marks,
The amount of deviation from the reference mark is measured, and the imaging characteristics of each of the plurality of projection optical systems are corrected according to the amount of deviation. As a result, the amount of deviation actually obtained by projection is directly measured to adjust the image forming characteristics of each projection optical system, so that an exposure apparatus capable of appropriately correcting the image forming characteristics of the projection optical system can be realized.

Also, the mask surface side first reference mark and the photosensitive substrate surface side first reference mark are integrally arranged on a block having sufficient rigidity to hold the mask surface side and the photosensitive substrate surface side first reference mark at corresponding positions on the mask surface and the photosensitive substrate surface. By doing so, the positional relationship between the mask-side first reference mark and the photosensitive-substrate-side first reference mark can always be kept constant, and the imaging characteristics of the projection optical system will not change over time due to changes in the environment. Even if it occurs, it is possible to realize an exposure apparatus that can perform the best correction again.

Further, by using the first reference mark on the mask surface side and the first reference mark on the photosensitive substrate surface side, the projection magnification of the projection optical system is set as a correction value for minimizing the distortion of each projected image by the projection optical system at both ends. , A value for adjusting at least one of the rotation and shift of the projected image is changed to change the imaging characteristic, and the changed mask surface side second fiducial mark or photosensitive substrate surface by the projection optical system at the both ends is changed. The second reference mark on the mask surface side or the second reference mark on the photosensitive substrate surface side so that the image of the second reference mark on the side and the fixed second reference mark on the surface of the photosensitive substrate or the second reference mark on the mask surface side are aligned. Are positioned by moving the second reference mark on the mask surface side and the second reference mark on the photosensitive substrate surface side, and projection is performed as a correction value that minimizes the distortion of each projected image by the plurality of projection optical systems. The mask surface side second reference for correcting the projection optical system by obtaining the value for adjusting at least one of the projection magnification, the rotation and the shift of the projection image of the academic system to correct the imaging characteristic. The mark and the second reference mark on the surface side of the photosensitive substrate can be correctly calibrated, and thus the mask and the photosensitive substrate can be scanned synchronously with respect to a plurality of projection optical systems so that the entire surface of the pattern area on the mask is correctly corrected. It is possible to realize an exposure device that can be transferred on top. Further, the accuracy of attaching the mask-side first reference mark and the photosensitive-substrate-side first reference mark to the block is rough and good, and the manufacturing becomes easier accordingly.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a scanning exposure apparatus according to the present invention.

FIG. 2 is a schematic diagram used to describe a mark configuration of a mask side reference mark and a photosensitive substrate side reference mark.

FIG. 3 is a schematic diagram used for explaining calibration of projection lenses at both ends using a mask-side fixing mark.

FIG. 4 is a schematic diagram for explaining calibration of projection lenses at both ends using a mask-side fixing mark.

FIG. 5 is a schematic diagram used for explaining calibration of a mask-side movable mark.

FIG. 6 is a schematic diagram for explaining calibration of a mask-side movable mark.

FIG. 7 is a schematic diagram for explaining adjustment of a projection lens using a mask side movable mark and a photosensitive substrate side reference mark.

[Explanation of symbols]

1 ... exposure device, 2 ... mask, 3 ... illumination system, 4 ...
Photosensitive substrate, 5 to 9 ... Projection lens, 10 ... Mask side reference mark, 11 ... Photosensitive substrate side reference mark, 12 to 16
...... Measuring instrument, 17-21 …… Lens adjustment mechanism, 22 ……
Blocks, 23, 24 ... Alignment microscope.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication H01L 21/30 526 A (72) Inventor Take Narabe 3 2-3 Marunouchi, Chiyoda-ku, Tokyo Stock Company Nikon

Claims (3)

[Claims] 1. A plurality of illumination optical systems for irradiating a plurality of partial areas in a pattern area of a mask with a light beam of a light source, and a plurality of illumination optical systems arranged along a predetermined direction and displaced from each other in a direction orthogonal to the predetermined direction. A plurality of projection optical systems that project the images of the plurality of partial regions by the light flux that has passed through the mask onto the photosensitive substrate by overlapping the positions of the adjacent images in the predetermined direction with each other; On the other hand, a scanning unit that scans the mask and the photosensitive substrate in synchronization with each other in a direction substantially orthogonal to the predetermined direction, and scans the mask and the photosensitive substrate with respect to the projection optical system. ,
In an exposure apparatus that transfers the entire surface of the pattern area of the mask onto the photosensitive substrate, both ends of the array of the plurality of projection optical systems at positions corresponding to each other on the mask surface and the photosensitive substrate surface. 2 arranged at conjugate positions with respect to the projection optical system of
A pair of mask surface side first reference marks and photosensitive substrate surface side first reference marks, at positions corresponding to each other on the mask surface and the photosensitive substrate surface, and in the predetermined direction corresponding to the overlapping positions. A plurality of mask surface side second reference marks and photosensitive substrates arranged in one row, one of which is fixed with respect to the mask surface side first reference mark and the photosensitive substrate surface side first reference mark, and the other of which is movable A surface side second fiducial mark, the mask surface side first fiducial mark and the mask surface side second
The amount of deviation of the reference mark between the corresponding plurality of projection optical systems and the first reference mark on the photosensitive substrate side and the second reference mark on the photosensitive substrate side, or the first reference mark on the photosensitive substrate side and the first reference mark Displacement amount measuring means for measuring the amount of displacement between the mask surface side first reference mark and the mask surface side second reference mark, and the images of the photosensitive substrate side second reference mark respectively corresponding to the plurality of projection optical systems. An exposure apparatus comprising: a lens adjusting unit that corrects image forming characteristics of each of the plurality of projection optical systems according to the shift amount measured by the shift amount measuring unit. 2. The mask surface side first reference mark and the photosensitive substrate surface side first reference mark are integrated with a block having sufficient rigidity to hold the mask surface side and the photosensitive substrate surface side corresponding positions on the mask surface and the photosensitive substrate surface. The exposure apparatus according to claim 1, wherein the exposure apparatus is arranged in the. 3. The displacement amount measuring means minimizes the distortion of each projected image by the projection optical systems at the both ends by using the mask surface side first reference mark and the photosensitive substrate surface side first reference mark. As the correction value to be obtained, a value for adjusting at least one of the projection magnification of the projection optical system, the rotation of the projection image, and the shift is obtained, and the lens adjusting means projects the projections of the both ends according to the correction value. At least one of a magnification of an optical system, a rotation and a shift of the projected image is changed to change an imaging characteristic, and the movable second mask surface side reference by the changed projection optical systems at both ends. The mask surface side second reference so that the image of the mark or the photosensitive substrate surface side second reference mark matches the fixed photosensitive substrate surface side second reference mark or the mask surface side second reference mark. Mar Or, the photosensitive substrate surface side second reference mark is moved and positioned, and the displacement amount measuring means uses the mask surface side second reference mark and the photosensitive substrate surface side second reference mark to project the plurality of projections. A value for adjusting at least one of the projection magnification of the projection optical system, the rotation of the projection image, and the shift is obtained as a correction value that minimizes the distortion of each projection image by the optical system. The image forming characteristic is corrected by changing at least one of the magnification of the plurality of projection optical systems, the rotation of the projection image, and the shift of the projection image corresponding to the correction value. The exposure apparatus according to claim 1.