JPH06302501A - Aligner - Google Patents

Abstract

PURPOSE:To make it possible to form an ideal dimmed region within the exposure field on a photosensitive substrate to be exposed without providing a reticle itself with a means for dimming in an aligner for image synthesization. CONSTITUTION:The title aligner consists of a driving apparatus 18A and 18B and a control apparatus 19. The driving apparatus 18A and 18B alters the setting of a reticle blind located in a position condugate with a reticle 10 in an illumination optical system wherein the reticle 10 is irradiated with the luminous flux from a light source 1. The control apparatus 19 drives the driving apparatus 18A and 18B in synchronization with the operation of a shutter 3. The control apparatus 19 drives the driving apparatus to move the reticle blind 7 within the field wherein images are to be superposed during the exposure of a photosensitive substrate 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus used for manufacturing a semiconductor device, a liquid crystal display substrate, etc., and particularly to a large area by overlapping part of the pattern of unit areas with each other on a photosensitive substrate. Exposure apparatus for performing so-called screen composition for forming a pattern

[0002]

2. Description of the Related Art In this type of exposure apparatus, in order to cope with an increase in the size of a sample to be exposed, the exposure area of the sample is divided into a plurality of unit areas and the exposure according to each area is repeated, and finally, A screen synthesizing method for synthesizing a desired pattern is used. When performing this screen composition, the drawing error of the reticle for pattern projection, the aberration of the lens of the projection optical system,
In order to prevent the occurrence of a pattern break at the boundary position of each exposure region due to the positioning error of the stage for positioning the sample, exposure is performed by superimposing the boundary of each exposure region by a small amount. However, when the exposure areas are overlapped, the exposure amount of this portion is doubled, and the line width of the joint portion of the pattern changes depending on the characteristics of the photosensitive agent. Further, when screens are combined, a step may occur at the joint portion of the pattern due to the displacement of the positions of the adjacent exposure regions, and the device characteristics may be impaired. Furthermore, when multiple exposure devices share the process of superimposing the screen-synthesized patterns in multiple layers, the overlay error in the exposure area of each layer may be affected by the lens aberration and positioning accuracy of each exposure device. Changes discontinuously with
In particular, in an active matrix liquid crystal device, the contrast changes intermittently at the pattern seam portion, resulting in a significant deterioration in device quality.

As a means for eliminating the above inconveniences in screen composition, Japanese Examined Patent Publication No. 63-49218 discloses a dim light that reduces the amount of transmitted light at a position corresponding to the pattern joint portion of a reticle or a filter to be laid on the reticle. It is disclosed that a means is provided to make the exposure amount of the pattern overlapping portion substantially coincide with the exposure amount of the other portion.

[0004]

However, the means described in the above publication has the following problems. First, when the reticle itself has a light-reducing characteristic, the number of man-hours for manufacturing the reticle increases, and the possibility that a pattern defect may occur during manufacturing also increases the burden on the reticle manufacturing process. on the other hand,
When a filter that overlaps the reticle is used, there is a problem in maintenance and management of the reticle, such that the reticle is likely to be damaged or contaminated when the filter is attached or detached.
In addition, since a pellicle with a certain thickness is often provided before and after the reticle to prevent foreign matter such as dust from adhering to the pattern, at least the pattern of the reticle should be separated from the reticle pattern by the thickness of the pellicle. Therefore, it becomes difficult to obtain an ideal dimming characteristic on the pattern. Furthermore, it is necessary to prepare a dedicated filter for each reticle, and the labor required for filter manufacturing and maintenance cannot be ignored.

An object of the present invention is that it is not necessary to provide a pattern transfer original plate such as a reticle with a light-reducing characteristic or to prepare different light-reducing means for each original plate, and it is ideal on the original plate. An object of the present invention is to provide an exposure apparatus that can obtain a dimming characteristic.

[0006]

In order to solve the above problems, in the present invention, an illumination optical system (2, 6, 8, 9) for irradiating a reticle (10) with a light beam from a light source (1), and a reticle. An illumination area setting means (7) which is arranged at a position substantially in the conjugate optical system and which can arbitrarily set an area on the reticle illuminated by the light flux, and an image (P1, P2) of the pattern on the reticle are provided. An exposing means (11) for exposing on a photosensitive substrate (12), and forming images so that a part (R1, R2) of the pattern image overlaps different regions on the photosensitive substrate. An exposure apparatus for performing exposure comprises a control means (19) for controlling the illumination area setting means (7) so that the light amount of a part of the image given by the exposure changes substantially continuously during the exposure. To do.

An illumination optical system (2, 6, 8, 9) for irradiating the reticle (10) with a light beam from the light source (1),
A field diaphragm device (7) arranged at a position almost conjugate with the reticle and capable of arbitrarily setting an area on the reticle illuminated by the light flux, and a pattern image (P1, P1 on the reticle).
Exposure means (1) for exposing P2) onto the photosensitive substrate (12)
1) and an exposure apparatus that performs exposure while forming images so that the peripheral portions (R1, R2) of the image of the pattern overlap with each other in different areas on the photosensitive substrate, the exposure apparatus is synchronized with the exposure. A field stop control means (19) for changing the amount of light at the peripheral portion of the image on the photosensitive substrate by displacing the edge position of the field stop device is provided.

[0008]

In the present invention, the means for continuously changing the illumination range of the reticle within the range corresponding to the overlapping portion of the images of the reticle during exposure of the photosensitive substrate is provided. The amount of exposure in a part changes continuously. That is, 2 as shown in FIGS.
When exposing two different pattern areas A and B so that the hatching portions overlap each other, first, as shown in FIG. 7C, the reticle blind 7 is set for the white area of the pattern area A. Then, as shown in FIG. 7D, while illuminating the pattern area A (during exposure), the reticle blind 7 corresponding to the hatched portion of the pattern area is driven in the direction of the arrow. As a result, the exposure amount on the photosensitive substrate continuously decreases at the portion corresponding to the hatched portion, as shown in FIG.

[0009]

1 is a diagram showing a schematic structure of an exposure apparatus according to a first embodiment of the present invention. The illumination light from the ultra-high pressure mercury lamp 1 as the exposure light source is condensed by the elliptical mirror 2,
The light enters the wavelength selection filter 5 via the shutter 3 and the reflecting mirror 4. The wavelength selection filter 5 passes only the wavelength required for exposure (generally the wavelength of g-line or i-line), and the illumination light that has passed through the wavelength selection filter 5 is a light flux with a uniform illuminance distribution in the fly-eye integrator 6. To reach the reticle blind 7. The reticle blind 7 changes the size of the opening S to adjust the illumination range on the reticle by the illumination light. A part of the light flux emitted from the fly-eye integrator 6 is reflected by the half mirror 16 and enters the integrated exposure amount meter 17, and the opening / closing time of the shutter 3 is controlled based on this information. That is, the exposure amount is controlled.

The illumination light that has passed through the opening S of the reticle blind 7 is reflected by the reflecting mirror 8 and enters the lens system 9, and the image of the opening S of the reticle blind 7 is formed on the reticle 10 by this lens system 9. , The desired area of reticle 10 is illuminated. An image of the pattern existing in the illumination range of the reticle 10 is imaged on the photosensitive substrate 12 such as a wafer or a glass plate by the projection optical system 11, and thus the photosensitive substrate 1
The image of the pattern of the reticle 10 is exposed in the two specific areas.

The photosensitive substrate 12 is fixed on the stage 13. The stage 13 is a known one in which a pair of blocks movable in directions orthogonal to each other are superposed, and the position of the stage 13 is a moving mirror on the stage 13 for a laser beam 15 from a laser interferometer system (not shown). 14
The position of the photosensitive substrate 12 in the horizontal plane is adjusted. When synthesizing screens, 1 for a certain reticle (pattern area)
After the exposure is completed, the reticle 10 is exchanged and the stage 13 is driven to position another exposure area of the photosensitive substrate 12 with respect to the projection optical system for exposure. After that, the same procedure is repeated each time the exposure is completed to expose the entire area of the photosensitive substrate 12. A plurality of types of patterns are formed on one reticle, and the reticle blind 7 is used to change the irradiation area in the reticle (change to a different pattern area) in association with the change of the exposure area of the photosensitive substrate 12. Synthesis may be performed.

The blind 7 is formed by combining blades 7A and 7B bent in an L-shape as shown in FIG. 4 in a state of being orthogonal to the optical axis AX of the illumination light, thereby forming a rectangular opening S. The positions of the blades 7A and 7B are adjusted by the drive mechanisms 18A and 18B shown in FIG. 1 to change the size of the opening S. As shown in FIGS. 5 and 6, the drive mechanisms 18A and 18B include a first block 710 to which the blades 7A and 7B are fixed, a second block 711 and a third block 711.
The block 712 is overlapped, and the first block 710 is moved along the guide grooves y1 and y2 by a feed mechanism (not shown) which is a combination of a servo motor and a ball screw, and the second block 711 is moved. Guide groove x
1 and x2 to move the blades 7A and 7B in a plane orthogonal to the optical path of the illumination light. As shown in FIG. 6, the drive mechanisms 18A and 18B are arranged on the opposite sides of the blades 7A and 7B, and the respective third blocks 712 are attached to the main body portion (not shown) of the exposure apparatus by a frame (not shown). It is fixed together.

The shutter 3, the integrated exposure meter 17,
The drive mechanisms 18A and 18B are both controlled by the controller 19. That is, after setting the reticle blind 7 for the pattern area of the reticle 10 to be exposed,
The shutter 3 is opened in response to a command from the control device, and exposure of the photosensitive substrate 12 is started. The movement of the reticle blind 7 is started in synchronization with the operation of the shutter 3,
The integrated exposure amount meter 17 measures the integrated exposure amount. The shutter 3 is closed and the movement of the reticle blind 7 is terminated when the information from the integrated exposure meter 17 reaches a predetermined exposure amount. The moving speed of the reticle blind 7 is set so that the reticle blind moves while the shutter 3 is open by a distance corresponding to the area to be combined.

Generally, in the case of this type of exposure apparatus, the exposure time is determined by the sensitivity of the photosensitizer and the like. Therefore, when applying the present invention, it is necessary to change the moving speed of the blind in accordance with the exposure time. Moreover, it is common to use an ultra-high pressure mercury lamp as a light source. However,
The illuminance of the ultra-high pressure mercury lamp deteriorates as it is used. Therefore, even if the exposure amount is constant, the exposure time becomes longer as the lamp usage time elapses. When the exposure amount is D (mJ / cm ² ) and the exposure illuminance is I (mW / cm ² ), the exposure time T (sec) is expressed by the following formula 1.

[0015]

[Equation 1]

In the equation (1), the exposure amount D is given as data in advance, but the exposure illuminance I can change. In addition, the overlapping width of the exposed areas is W (m
m), the distance L corresponding to the width W of the reticle blind during the exposure time T (the magnification of the lens system 9 with respect to the reticle of the reticle blind is M ₁ , and the magnification of the projection optical system 11 with respect to the photosensitive substrate of the reticle is M). _{If it is 2} , L = W /
The moving speed V (mm / sec) of the reticle blind is expressed by the following mathematical formula 2 because it has to move by M ₁ · M ₂ ).

[0017]

[Equation 2]

Since the value of the width L is determined at the stage of designing the reticle, it is given as data like the exposure amount D. Therefore, the moving speed of the reticle blind can be calculated by knowing the value of the exposure illuminance I. In the exposure apparatus shown in FIG. 1, the exposure illuminance I can be obtained by detecting the output of the integrated exposure amount meter 17. Specifically, prior to the exposure operation, the shutter 3 is opened and the integrated exposure meter 17
The output value when the output of is stable is stored. The value obtained by multiplying this value by a constant coefficient corresponds to the exposure illuminance I. This operation is performed at the time of replacing the photosensitive substrate 12 or at the beginning of a lot when a plurality of photosensitive substrates are regarded as one lot. The moving speed of the reticle blind is determined from Equation 2 based on the exposure illuminance I obtained here, and stored in the control device 19.

Now, FIG. 8 is a diagram showing an exposure image and an exposure amount distribution on the photosensitive substrate 12 when the size of the opening S of the blind 7 is appropriately determined and exposure is performed without the reticle 10. In each of the different shots P1 and P2 as shown in FIG. 8A, the shaded areas R1 and R2 become the light reduction area due to the blind movement, and the exposure amount in this area decreases. When both shots are combined as shown in FIG. 8 (B), the exposure amount distribution for each shot is as shown in FIG. 8 (C), and one of the light reduction amounts is in the overlapping range of the light reduction regions R1 and R2. The change is made to compensate for the variation of the other dimming amount, and as a result, as shown in FIG. 8D, the dimming region R1,
The combined exposure amount in the overlapping range of R2 matches the exposure amount of the white portion in FIG. 8A which is not affected by the blind movement.

Next, screen composition in the exposure apparatus according to the present embodiment will be described. FIG. 9 shows an example in which the photosensitive substrate 12 is divided into four rectangular exposure regions Ra to Rd to synthesize the pattern Pr.
As shown in 0, the four reticles 10a to 10d corresponding to the exposure regions Ra to Rd are used in order. Incidentally, reticle 1
0a to 10d are drawn so that only the overlapping portion at the time of screen combination has the same pattern.

A light-shielding band IB having a transmittance of 0% that completely blocks the passage of light is formed around the reticles 10a to 10d. Although not shown in FIG. 9, the boundary portions of the exposure regions Ra to Rd are overlapped by a desired amount (corresponding to L and W described above),
The blades 7A and 7B of the reticle blind 7 are positioned during each exposure so that the dimming area due to the blind movement coincides with the overlapping portion of the exposure areas Ra to Rd.

That is, when the upper left exposure area Ra in FIG. 9 is exposed, as shown in FIG. 10A, the blade 7A located on the right side and the lower side of the reticle 10a has its dimming area from the light shielding band IB. The blade 7B positioned so as to project and located on the left side and the upper side of the reticle 10a.
Are positioned so that they are completely retracted into the light-shielding band IB.

When the upper right exposure area Rb is exposed, as shown in FIG. 10B, the light-reducing areas of the blades 7A and 7B are located on the left side and the lower side of the reticle 10b.
The blades 7A and 7B are positioned so as to project from the blades. When the lower left exposure area Rc is exposed,
As shown in (C), the blades 7A and 7B are positioned so that the dimming regions of the blades 7A and 7B project from the light-shielding band IB on the right side and the upper side of the reticle 10c.
Then, when exposing the lower right exposure region Rd,
As shown in (D), the blades 7A and 7B are positioned so that the dimming regions of the blades 7A and 7B project from the light-shielding band IB on the left side and the upper side of the reticle 10d.

As a result of the above operation, in the overlapping portion of the exposure areas Ra to Rd, the dimming area in the previous exposure and the dimming area in the subsequent exposure overlap as shown in FIG. 8B, and these overlapping portions. The combined exposure amount at 8 is equal to that at other portions as shown in FIG. Therefore, the exposure amount of the pattern Pr becomes uniform, and the line width does not change even at the joint portion of the pattern Pr.

Further, according to the above, the step at the joint portion of the pattern is eliminated. This point will be described with reference to FIG.
FIG. 11 (A) shows screen composition by the conventional method.
In this example, when the positional deviation of δ occurs between the adjacent exposure areas, a step difference is generated in the joint portion of the patterns Pr1 and Pr2 by the same amount. On the other hand, in the case of this embodiment,
As shown in FIG. 11B, even if the positional deviation of δ occurs in the adjacent exposure areas, the left and right patterns Pr1, Pr2
Are smoothly continuous as shown by the thick line in the figure.

That is, since the joints of the patterns Pr1 and Pr2 match the dimming range (range of width W) of the exposure region, the exposure amount at each cross-section position d1 to d5 of the joints of the patterns Pr1 and Pr2 is as shown in the figure. As shown in FIG. 11 (C), it decreases toward each edge. The cross-section position d1
The waveform showing the exposure amount distribution of the patterns Pr1 and Pr2 at d5 appears with a shift amount δ of the exposure region shifted in the left-right direction in FIG. 11C.

Since the combined exposure amounts at the positions where the patterns Pr1 and Pr2 are completely overlapped with each other are equal, the combined exposure amounts at the cross-section positions d1 to d5 in FIG. 11B show a distribution as shown in FIG. 11D. , The maximum values of the combined exposure amount at each cross-section position d1 to d5 are all equal. With respect to such an exposure amount distribution, when the resist characteristics are determined so that the portion exceeding the constant exposure amount Qc (50% of the maximum exposure amount in the illustrated example) remains on the photosensitive substrate 12 after development, FIG. As shown in (E), the pattern width at the cross-section positions d1 to d5 is constant, and the patterns Pr1 and Pr2 are smoothly continuous while maintaining a constant width as shown by the thick line in FIG. 11 (B).

When the joints of the patterns Pr1 and Pr2 are smoothly continuous in this way, discontinuous changes in overlay error at the joints of the respective layers are suppressed even when the screen synthesis is repeated for many layers. Therefore, even in the case of the liquid crystal device, the discontinuous change in the contrast at the joint portion of the screen is eliminated and the display quality is improved. Here, as is clear from FIG. 11B, the degree of change in the seam portion of the pattern becomes gentler as the width W of the overlapping portion of the pattern is increased. However, if the width W is made too large, the number of screen combinations increases and the efficiency decreases, so the width W may be set on the basis of the degree to which human eyes cannot detect a change when used in a liquid crystal device. Generally, it is sufficient to set it to about 5 to 10 mm.

As described above, according to the exposure apparatus of this embodiment, the reticle 1 is exposed during the exposure of the photosensitive substrate 12.
Since the control device 19 that moves the reticle blind 7 within the range in which the images of 0 are superimposed is provided, ideal light reduction characteristics can be obtained in the peripheral portions R1 and R2 of the images on the photosensitive substrate. The exposure amount at the joint portion of the pattern can be accurately controlled to maximize the effect of dimming.

Another example of the control of the movement of the reticle blind will be described with reference to FIG. FIG. 2A is the same as FIG.
The output obtained by the integrated exposure meter 17 shown in
This is equivalent to one obtained by one shutter opening / closing operation. FIG. 2B shows a change in moving speed of the reticle blind with time. That is, in this example, the voltage obtained by multiplying the output of the integrated exposure dose meter by an appropriate multiplier is used as it is as the speed command voltage for moving the reticle blind. In this case, even if the illuminance of the light source deteriorates, the speed of the reticle blind automatically follows and slows down, so that it is not necessary to previously measure the output of the integrating exposure meter as described above. Furthermore, since the output of the integrated exposure amount meter is output according to the opening / closing of the shutter, it is possible to move the reticle blind in perfect synchronization with the shutter. Therefore, the calculation by the above formula 2 is unnecessary. Incidentally, the above-mentioned appropriate multiplier means that the movement amount of the reticle blind becomes the width L when the reticle blind is moved based on the waveform showing the change of the moving speed in FIG. 2B. It is a multiplier. This multiplier is also a value that is inversely proportional to the exposure amount D. A block diagram of the control system of the example shown in FIG. 2 is shown in FIG.

The output of the integrated exposure meter 17 is amplified by the amplifier 21, and the result is input to the integrating circuit 22 and the multiplier 25. On the other hand, the above-mentioned multiplier is output from the output port of the microprocessor 23 and input to the other input of the multiplier 25 via the D / A converter 24. Multiplier 2
The output from 5 is input to the servo circuit 26 and drives the motor 27 for driving the reticle blind.

In the above embodiment, the drive of the reticle blind is controlled based on the output of the integrated exposure meter. However, if the fluctuation of the illuminance of the light source is negligible, simply opening and closing the shutter A configuration in which the drive of the reticle blind is controlled in synchronization may be used. By the way, in the above-mentioned embodiment, the blades 7A and 7B of the reticle blind 7 for adjusting the illumination range of the reticle 10 are moved during the exposure, but this is not necessary when the screen synthesis is performed in the one-dimensional direction. No problem. However, as shown in FIG. 9 described above, when two-dimensional screen synthesis is performed, there is a portion in which the four pattern regions overlap each other in the exposure region on the photosensitive substrate, and the exposure amount of this region is different from that of the other. It will be larger than the area. How to deal with this case will be described below.

FIG. 12 is a view showing the schematic arrangement of an exposure apparatus according to the second embodiment of the present invention. The basic structure is the same as that of the device shown in FIG. 1, but the reticle blind 7 is used.
ND filter 30 having a configuration in which the transmittance of the edge portion gradually changes to at least two opposing edges of the four edges of the blade of FIG.
The difference is that an ND blind 30 composed of A and 30B is provided. This is configured such that a part of the edges of the plurality of blades corresponding to the area to be subjected to screen composition is blind-moved as in the above-described embodiment, and the other blades are dimmed in the overlapping portion by the ND filter. It is configured to form a region. That is, when the screen combination as shown in FIG. 9 is performed, for example, when the exposure regions Ra and Rb or Rc and Rd are overlapped, the respective dimming regions are formed by the blind movement described above, and the exposure region R
The attenuating region when a and Rc or Rb and Rd overlap is formed by using an ND blind. With such a configuration, the exposure amount per pattern region of the portion where all four pattern regions overlap in the exposure region on the photosensitive substrate is reduced, and the exposure amount of this portion is different from that of other regions. Will be equivalent. Therefore, good screen composition can be achieved even when screen composition is performed in two directions.

In this embodiment, the ND filter 30A, the blade which does not require dimming at the time of screen composition,
30B is retracted from the illumination area set by the blades 7A and 7B. In this case, the light-shielding band formed on the reticle is N
The width can be set narrower than the width of the dimming area by the D filters 30A and 30B, and the reticle can be effectively used. Incidentally, if the ND filters 30A and 30B are integrally formed with the blades 7A and 7B, the light-shielding band on the reticle needs to have a width equal to or greater than the width of the dimming region of the ND filters 30A and 30B. The ND filters 30A and 30B separated from the blades 7A and 7B are attached to the blades 7A and 7B.
You may provide the same light-shielding plate 31A, 31B.

In the above example, the ND blind is arranged near the reticle blind, but the optical system 32 is arranged as shown in FIG.
The D blind 30 may be arranged in a conjugate relationship. In this case, the ND blind 30 is configured to include blades 30A and 30B configured only with an ND filter and a moving mechanism (not shown) that drives these blades 30A and 30B. In this example, the ND blind 30 is at a position conjugate with the blind 7, so that the reticle 1
An ideal dimming characteristic can be obtained at zero.

The ND blind used for the two-direction screen combination may be configured not only by a general optical neutral density filter but also by means such as liquid crystal or EC.
In addition, the dimming characteristic due to the blind movement or the ND blind is not limited to the example in which the amount of transmitted light is linearly reduced in proportion to the distance from the center (optical axis AX) of the opening S, and synthetic exposure in the overlapping portion of the exposure region is performed. If the amount is substantially the same as the exposure amount of the other portion, it may be changed in a curve. It is also possible to reduce the light by shifting the lens focus and blurring the edge image of the blind aperture. That is, in addition to the conventional blind, the second blind may be provided so as to be displaced in the optical axis direction, and the image of the aperture of the second blind may be blurred on the reticle to reduce the light.

[0037]

As described above, according to the present invention, the reticle blind for setting the illumination area on the reticle is configured to move within the range of the portion where the patterns should be superposed during the exposure on the photosensitive substrate. The exposure amount at the seam portion diminishes almost continuously. Therefore, the exposure dose in the pattern overlapping portion becomes almost equal to the exposure dose in the other portions, the line width at the pattern joint portion is kept substantially constant, and there is no step or overlay error at the pattern joint portion. Continuous changes disappear.

Further, since the reticle blind that gives the light reduction effect is spaced apart from the reticle, it is not necessary to give the reticle its own light reduction characteristic, and there is no risk of damage or contamination of the reticle, and the reticle is manufactured. The burden of maintenance is reduced. Furthermore, since the dimming area can be adjusted,
The same reticle blind can be used regardless of the size of the reticle and changes in the overlay position of the exposure area.
Since it is not necessary to prepare various types of dimming means for each reticle, the labor required for manufacturing the dimming means and maintenance management is reduced.

[Brief description of drawings]

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

2A is a diagram showing an output obtained by an integrated exposure meter of the exposure apparatus shown in FIG. 1, and FIG. 2B is a diagram showing a change in moving speed of the reticle blind of the exposure apparatus shown in FIG.

FIG. 3 is a block diagram of a control system of another example of the embodiment shown in FIG.

FIG. 4 is a front view of a blade portion of the reticle blind.

FIG. 5 is a diagram showing a schematic configuration of a drive mechanism of a reticle blind.

FIG. 6 is a diagram showing a schematic configuration of a reticle blind and a drive mechanism.

FIG. 7 is a diagram showing a positional relationship between a reticle and a blade when screens are combined.

FIG. 8 is a diagram showing a relationship between an exposure image on the photosensitive substrate 11 and an exposure amount.

FIG. 9 is a diagram showing an example of screen synthesis.

FIG. 10 is a diagram showing an arrangement of a reticle and a reticle blind when performing screen synthesis.

FIG. 11 is a diagram for explaining the reason for eliminating the step at the joint portion of the pattern.

FIG. 12 is a diagram showing a schematic configuration of an exposure apparatus according to a second embodiment of the present invention.

13 is a diagram showing a modification of the example shown in FIG.

FIG. 14 is a view showing the arrangement of reticle blinds and ND blinds of the exposure apparatus according to the second embodiment.

[Explanation of symbols]

 1 Ultra High Pressure Mercury Lamp 3 Shutter 7 Reticle Blind 7A, 7B Blade 10, 10a, 10b, 10c, 10d Reticle 12 Photosensitive Substrate 17 Integrated Exposure Meter 18A, 18B Driving Device 19 Control Device 30 ND Blind 30A, 30B ND Filter 31A, 31B light shield

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masakazu Murakami 3 2-3 Marunouchi, Chiyoda-ku, Tokyo Inside Nikon

Claims (4)

[Claims] 1. An illumination optical system for irradiating a reticle with a light beam from a light source, and an area on the reticle which is arranged at a position in the illumination optical system substantially conjugate with the reticle and which is illuminated by the light beam is arbitrarily set. An illumination area setting unit that can be set and an exposure unit that exposes an image of the pattern on the reticle onto a photosensitive substrate are provided, and a part of the image of the pattern is different from each other for different regions on the photosensitive substrate. In an exposure apparatus that performs the exposure while forming the images so as to overlap, the illumination area setting means is provided so that the light amount of a part of the image given by the exposure changes substantially continuously during the exposure. An exposure apparatus comprising control means for controlling. 2. The exposure apparatus further comprises an integrated exposure dose meter for detecting an integrated exposure dose during the exposure, and the control means performs the control based on information from the integrated exposure dose meter. The exposure apparatus according to claim 1, wherein: 3. The control means, when exposing a plurality of the patterns on the photosensitive substrate to different positions on the photosensitive substrate while overlapping the peripheral portions of the images with each other, The exposure apparatus according to claim 1, wherein the illumination area setting means is controlled so that the light amount at the overlapping position becomes substantially equal to the light amount outside the range of the overlapping position. 4. An illumination optical system for irradiating a reticle with a light beam from a light source, and a field diaphragm arranged at a position substantially conjugate with the reticle and capable of arbitrarily setting an area on the reticle illuminated by the light beam. An apparatus and an exposure unit that exposes the image of the pattern on the reticle onto a photosensitive substrate, and displays the image so that the peripheral portions of the image of the pattern overlap different areas on the photosensitive substrate. In an exposure device that performs the exposure while forming, a field stop control unit that changes the light amount of the peripheral portion of the image on the photosensitive substrate by displacing the edge position of the field stop device in synchronization with the exposure. An exposure apparatus comprising: