JP2000331909A - Scanning projection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high performance scanning projection aligner for establishing both processing capabilities and optical precision while operating proper exposure based on a process condition. SOLUTION: In this aligner, a mask 1 and a glass plate 4 are simultaneously moved to plural parallel projecting optical systems 3A-3E, and the pattern image of the mask 1 is transferred and exposed to projecting regions P1-P5 on the glass plate 4 by exposed lights from each projecting optical system 3A-3E. Each projecting optical system 3A-3E changes the width of the slit according to the scanning speed, and enlarges/reduces each projecting region P1-P5 while holding the mutual corresponding relation. Thus, the exposure can be increased and decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for manufacturing a liquid crystal display substrate or a semiconductor element, and more particularly to a scanning type exposure apparatus for transferring and exposing a pattern image of a mask onto a photosensitive substrate by synchronously moving the mask and the photosensitive substrate. The present invention relates to an exposure apparatus.

[0002]

2. Description of the Related Art In recent years, liquid crystal display substrates which can be made thinner have been frequently used as display elements for personal computers and televisions. The liquid crystal display substrate is manufactured by patterning a transparent thin-film electrode into a desired shape on a glass plate having a rectangular shape in a plan view by a photolithography technique. As an apparatus for performing the photolithography, a projection exposure apparatus for transferring and exposing an exposure pattern formed on a mask to a photoresist layer on a glass plate via a projection optical system is used.

With respect to the liquid crystal display substrate, the area of the glass plate is increased in order to improve the visibility of the screen, while in order to improve the productivity, one to a large number of liquid crystal display substrates are used. Is obtained. In order to respond to these demands, the step-and-scan type scanning exposure apparatus responds to the enlargement of the glass plate by increasing the size of the mask and the projection optical system.

The amount of light required to expose a photoresist layer, that is, the amount of exposure, is generally represented by the product of the illuminance on the glass plate and the irradiation time. In the case of a scanning type exposure apparatus, the amount of exposure is The product of the width (exposure width) of the slit in the scanning direction and the illuminance on the glass plate is divided by the scanning speed, and the exposure amount is controlled by adjusting the scanning speed.

Since the amount of exposure depends on the so-called process conditions such as the sensitivity and thickness of the photoresist layer, each time a new photoresist layer is exposed, a specific value corresponding to this is required. The exposure amount required for an exposure apparatus is not always constant.

On the other hand, in the conventional scanning exposure apparatus, since the illuminance and the exposure width on the glass plate are fixed, for example, when the required exposure amount increases due to a change in the process conditions, the scanning speed is set to a low value. And the time required for exposure increases.

That is, when the exposure amount increases, the time required for exposure per glass plate becomes longer, and as a result, the processing capacity decreases. Therefore, in a conventional scanning type exposure apparatus, a specific exposure amount that is frequently used is assumed, and various components of the exposure apparatus such as an increase in the size of a light source lamp (increase in illuminance) and an improvement in the transmittance of an optical member to meet the exposure amount condition. In order to improve the processing capability, the exposure time is not extended by improving the performance of.

[0008]

However, when the size of the light source lamp is increased, the distance between the electrodes is increased and the bright spot is increased. However, optically, the light source is as small as possible, that is, it is desirable to use a so-called point light source. However, there is a limit to the size of the light source lamp. In addition, it is difficult to obtain a higher processing ability because there is a limit in improving the transmittance. Further, if the exposure apparatus is adapted to an arbitrary exposure amount, the exposure time must be adjusted, and it is difficult to further improve the processing ability.

The present invention has been made in view of the above circumstances, and provides a high-performance scanning type exposure apparatus which achieves both processing performance and optical accuracy while performing appropriate exposure based on process conditions. It is intended to be.

[0010]

As means for solving the above-mentioned problems, an exposure apparatus having the following configuration is employed. That is, the exposure apparatus according to the present invention includes a light source unit, an illumination optical system (L) for illuminating a plurality of portions of a mask (1) having a pattern with a light beam from the light source unit, and a substrate (4) having a photosensitive layer. And a plurality of projection optical systems (3A to 3E) for projecting a pattern onto the substrate (4), each of which is disposed at an optically conjugate position with the mask (1). Aperture mechanisms (S1 to S5) for limiting the pattern to be performed, and the plurality of aperture mechanisms (S1 to S5).
Aperture control mechanism (11A, 11B) for changing shape of 5)
And a scanning mechanism (2, 5) for synchronously scanning the mask (1) and the substrate (4), and an aperture control mechanism (11A, 1).
1B) is characterized in that the width of the plurality of aperture mechanisms (S1 to S5) in the scanning direction of the mask (1) and the substrate (4) is controlled according to the scanning speed.

In the exposure apparatus according to the present invention, the shape of the aperture mechanism (S1 to S5) is changed to enlarge each projection area (P1 to P5) projected on the photosensitive substrate (4), or conversely. By reducing the size, the amount of exposure can be increased or decreased even while the scanning speed is kept constant. Also,
Even if exposure is performed with the same exposure amount, each projection area (P1 to P1)
By enlarging P5) and increasing the scanning speed, it is possible to improve the processing capability, or it is unavoidable that the processing capability is reduced, but it is possible to improve the optical accuracy by reducing the projection area (P1 to P5).

For example, when a large amount of exposure is required for exposure, a sufficient amount of exposure can be obtained without increasing the size of the light source lamp or improving the transmittance of the optical member as in the related art, and the processing capacity is reduced. Exposure can be minimized. Further, the magnification error has a larger variation as the projection area becomes wider. However, when high optical accuracy is required, the variation in the magnification error can be suppressed by reducing the projection area (P1 to P5) as described above. The optical accuracy can be improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a scanning exposure apparatus according to the present invention will be described with reference to FIGS. In this embodiment, the scanning direction of the mask and the glass plate is the X direction, the direction orthogonal to the X direction in the same plane as the mask and the glass plate is the Y direction, and the X and Y directions are the same.
The description will proceed with the direction orthogonal to the direction as the Z direction.

FIG. 1 shows a catadioptric optical system (for example,
1 shows a schematic configuration of a so-called multi-lens type scanning exposure apparatus using the optical system disclosed in 8-255746. This scanning type exposure apparatus comprises an illumination optical system L, a mask 1
Stage (scanning mechanism) 2 on which is mounted, a plurality of projection optical systems 3A to 3E, and a glass plate (photosensitive substrate)
And a substrate stage (scanning mechanism) 5 on which the stage 4 is placed.

The illumination optical system L is provided with an optical axis AX1 in the process of passing a light beam emitted from a light source unit such as an ultra-high pressure mercury lamp (not shown) through an optical fiber cable which branches into a plurality of beams on the way.
AX5 are set on a plurality of optical paths and irradiate the mask 1 with a wavelength selection filter (not shown), a fly-eye lens, and the like. Light beams emitted from the illumination optical system L are used as exposure light in different illumination areas M1 on the mask 1.
ＭM5 are illuminated.

The mask stage 2 is movable in the X direction by a driving device (not shown). A reflecting mirror 6a is provided at an edge of the mask stage 2 in the Y direction, and a laser interferometer 7 is provided at a position facing the reflecting mirror 6a.
a is arranged. Also, at the edge of the mask stage 2 in the X direction, a polarization beam splitter 6b, a λ / 4 plate 6c for changing the polarization direction of the laser beam passing through the polarization beam splitter 6b, a reference mirror 6d, and a corner cube 6e
The laser interferometer 7b is disposed at a position facing the reference mirror 6d, and the long mirror 7c is disposed at a position facing the corner cube 6e. Then, the moving distance of the mask stage 2 in the X direction, the displacement of the mask stage 2 in the Y direction at the time of scanning, and the amount of rotation of the mask stage 2 about the Z direction as a rotation axis are detected.

Each of the projection optical systems 3A to 3E is provided at a position corresponding to each of the above-described optical paths, and has an optical axis AX1 to AX1.
A pair of catadioptric optical systems 3A-3 arranged in the AX5 direction
E, and a field stop 8 arranged between each group of catadioptric systems arranged vertically.

Each of the projection optical systems 3A to 3E is an erecting equal magnification system, and irradiates a plurality of light beams passing through the mask 1 onto projection regions P1 to P5 on the glass plate 4 to illuminate the illumination regions M1 to M5. Is formed.

In the field stop 8, a material such as chromium having a high optical density is vapor-deposited on an optical member and is etched to form a trapezoidal slit (a stop mechanism) on the surface of the optical member as shown in FIG. What formed S1-S5 is used. The slits S1 to S5 are optical axes AX1 to AX5
Are provided so as to correspond to a plurality of optical paths along the optical path, and the cross section perpendicular to the optical axis of the light beam passing through the upper catadioptric system is shaped into a trapezoid.

The slits S1 to S5 are formed in a trapezoidal shape in plan view with upper and lower parallel sides facing in the Y direction, and slits adjacent in the Y direction (for example, S1 and S2, S2 and S3) in the X direction. They are arranged in two rows displaced by a fixed amount.
In addition, those that are adjacent to each other in the Y direction are brought close to the upper base (here, the longer side of the parallel opposite sides forming a trapezoid is the lower base and the shorter side is the upper base), and the end of each area is set. Are arranged so as to overlap the oblique sides located in the Y direction.

Returning to FIG. 1, each of the projection areas P1 to P5 is shaped into a trapezoid by slits S1 to S5 provided in the field stop 8, and projected onto the glass plate 4 according to the arrangement of the slits S1 to S5. ing. Needless to say, the projection optical systems 3A to 3E are also displaced by a predetermined amount in the X direction and overlap the oblique sides in the Y direction in correspondence with the arrangement of the projection areas P1 to P5. .

The substrate stage 5 can be moved in each of the X and Z directions by a driving device (not shown). A reflecting mirror 9a is provided on the edge of the substrate stage 5 in the Y direction, and a laser interferometer 10a is disposed at a position facing the reflecting mirror 9a. A polarizing beam splitter 9b is provided on the edge of the substrate stage 5 in the X direction.
And a λ / 4 plate 9c for changing the polarization direction of the laser beam that has passed through the polarization beam splitter 9b, a reference mirror 9d, and a corner cube 9e. A total of 10b is arranged, and a long mirror 10c is arranged at a position facing the corner cube 9e. Then, the moving distance of the substrate stage 5 in the X direction,
The displacement of the substrate stage 5 in the Y direction during scanning and the amount of rotation of the substrate stage 5 about the Z direction as a rotation axis are detected.

Further, as shown in FIG. 3, each group (e.g. 3A _U and 3A _D catadioptric optical system disposed vertically, 3B _U
And between 3B _D), the width of the X direction of each projection region P1~P5 projected on the glass plate 4, i.e. the projection area changing mechanism for enlarging / reducing the scanning direction of the exposure width (aperture control mechanism) 11A , 11B are installed below the field stop 8.

As shown in FIGS. 4 and 5, the projection area changing mechanism 11A (11B) includes a light shielding member 12 that blocks a part of a light beam passing through each of the slits S1 to S5, and a driving mechanism that drives the light shielding member 12. And The light blocking member 12 is movable in the X direction so as to block each of the slits S1 to S5 from the upper bottom side or the lower bottom side when viewed from each optical axis direction.

The driving mechanism 13 has an X
A rail portion 14 extending in the direction, a guide portion 15 fixed to the light shielding member 12, a linear motion mechanism 16 for reciprocating the guide portion 15 along the rail portion 14, and a motor 17 for driving the linear motion mechanism 16 And The linear motion mechanism 16 includes a nut portion 16 a fixed to the guide portion 15 and a nut portion 1.
A mechanism including a lead screw 16b screwed to 6a is employed. A coupling mechanism between the lead screw 16b and the motor 17 is provided with a clutch mechanism 18 for intermittently transmitting power.

In the scanning exposure apparatus configured as described above, the projection areas P1 to P5 projected on the glass plate 4 can be enlarged by operating the projection area changing mechanism 11A (11B). Conversely, it can be reduced. For example, as shown in FIG. 6, each light shielding member 12 provided corresponding to each of the slits S1 to S5 is +
When moved in the X direction, each of the projection areas P1 to P5 has a trapezoidal shape and a width in the X direction, that is, an exposure width in the scanning direction, while maintaining a state in which the hypotenuses overlap in the Y direction. And the projected area is enlarged. Further, as shown in FIG. 7, when each light shielding member 12 is moved in the −X direction, the exposure width and the projection area of each of the projection areas P1 to P5 are reduced.

As described above, by enlarging or reducing each of the projection areas P1 to P5, the exposure amount can be increased or decreased while the scanning speed is kept constant. Also,
Even if exposure is performed with the same exposure amount, the projection areas P1 to P5
It is unavoidable that the processing capacity is improved by increasing the scanning speed by increasing the scanning speed, or the processing capacity is reduced, but the projection areas P1 to P
5 can be reduced, and variation in magnification error can be suppressed to improve optical accuracy.

Further, conventionally, at the start and end of scanning, a light shielding area is provided on a mask because the exposure amount is not constant until the scanning speed becomes constant and exposure cannot be performed. Each projection area P1 to P5 is enlarged according to
By reducing the size, a constant exposure amount can be obtained from the start to the end of scanning, and the light-shielding area of the mask becomes unnecessary. Therefore, the size of the mask can be reduced by the light-shielding area.

Further, in the case where the periphery of the glass plate 4 is exposed, for example, in the vicinity of the periphery where the photoresist layer is thickened, each projection area is set to P1 to P4 while keeping the scanning speed constant.
By increasing P5 to increase the exposure amount, the exposure amount can be changed according to the thickness of the photoresist layer on the glass plate 4. Accordingly, accurate exposure processing can be performed without reducing the processing ability even in the peripheral portion where the photoresist layer tends to be non-uniform.

Next, a description will be given of a procedure for determining the scanning speed based on the process conditions given when performing exposure in the scanning exposure apparatus having the above-described configuration. In addition,
When determining the scanning speed, the case where the processing capability and the optical accuracy given together with the process conditions are prioritized will be described. As described above, the amount of exposure required for exposure depends on the process conditions such as the sensitivity and the thickness of the photoresist layer formed on the glass plate 4. Therefore, it is not possible for the exposure apparatus to automatically determine this. Impossible.

Therefore, first, the illuminance P on the glass plate 4 at that time is measured by an illuminometer (not shown) arranged on the glass plate 4. The method of determining the illuminance among the plurality of projection optical systems 3A to 3E is based on the conventional technique.

Next, based on the illuminance on the glass plate 4 and the required exposure amount, the scanning speed is calculated as follows in consideration of the performance to be prioritized. By the way, the exposure width is α [m
m] and the illuminance on the glass plate 4 is P [mW / c
m ² ] and the required exposure amount is E [mJ], the scanning speed VS [mm / s] is given by the following equation (I). VS = α × P / E (I)

[A. In the case of giving priority to processing capability] In this case, the exposure width is set to the maximum value (slit width in the X direction; see FIG. 6).
The scanning speed VS1 (= α1 × P / E) is calculated by setting α1 and substituting the same into equation (I).

When the scanning speed VS1 is determined, the projection area changing mechanism 11 is operated in the exposure apparatus to set each projection area P
Exposure is performed after setting the size of the exposure width of 1 to P5 to α1, and setting the scanning speed to VS1.

[B. In the case of giving priority to optical accuracy] In this case, the scanning speed VS2 (= α2) is set by setting the exposure width to a value (see FIG. 7) α2 at which the desired optical accuracy is guaranteed, and substituting this into the equation (I). × P / E) is calculated.

After the scanning speed VS2 is determined, the projection area changing mechanism 11 is operated in the exposure apparatus to set each projection area P
Exposure is performed after setting the size of the exposure width of 1 to P5 to α2 and setting the scanning speed to VS2.

Comparing the two, since the magnitude of the exposure width is α1> α2 even when the exposure amount E is constant, the scanning speed is VS1> VS2, and the former obtains a higher processing capability and the latter obtains a higher processing capability. It can be seen that optical precision is obtained. For example, when α1 is set to 20 mm and α2 is set to 16 mm, an improvement in scanning speed of up to 25% can be expected.

Incidentally, even with the exposure apparatus configured as described above, there is a limit to the scanning speed that can be handled. In particular, the mask stage and substrate stage, which are required to be driven at a constant speed while accurately maintaining the positional relationship between the mask and the glass plate, have a response frequency determined by the processing capability of the control system and the rigidity of the device itself. This is because the control ability is limited by factors.

For such a reason, when an enormous amount of exposure is required, there is a possibility that the scanning speed calculated by the above-mentioned formula (I) becomes lower than the lower limit of the range that can be handled. Further, when exposing a glass plate having a highly sensitive photoresist layer to light, the scanning speed may exceed the upper limit of a range that can be handled. Therefore, in such a case, the scanning speed is fixed to an upper limit or a lower limit of a range that can be dealt with, and the exposure width is changed within the range to cope with the case.

For example, the applicable range of the scanning speed VS is 3
When the required exposure amount E is specified to be 800 [mJ] when the illuminance P on the glass plate 4 is 130 [mW / cm ² ] and the exposure width W is 16 [mm / s].
In the conventional exposure apparatus fixed at [mm], the scanning speed VS calculated based on the equation (I) is VS = 16 × 130/800 = 2.6 [mm / s] Exposure could not be performed because it was below the lower limit.

However, in the exposure apparatus of this embodiment, the exposure width W required by fixing the scanning speed at the lower limit of 3 [mm / s] becomes W = 3 × 800/130 = 18.46 [ mm], the exposure can be performed by changing the exposure width W to this value.

In the conventional exposure apparatus, the lower limit of the exposure amount E is E = 16 × 130/200 = 10.4 [mJ]. However, the exposure apparatus of the present embodiment has a variable exposure width W. Therefore, assuming that the minimum value of the exposure width W that can be performed is 1 [mm], if the exposure width W is reduced to this size, the lower limit of the exposure amount E is E = 1 × 130/200 = Since it is 0.65 [mJ], exposure can be performed even when an exposure amount smaller than the conventional lower limit is required.

As described above, according to the scanning exposure apparatus configured as described above, the shapes of the slits S1 to S5 are changed to enlarge the projection areas P1 to P5 projected on the glass plate 4. By reducing / reducing, it is possible to increase or decrease the exposure amount even while keeping the scanning speed constant. Further, even if the exposure is performed with the same exposure amount, the processing capacity can be improved by enlarging each of the projection areas P1 to P5 and increasing the scanning speed. It is possible to improve the optical accuracy by reducing the scanning speed and reducing the scanning speed. Thus, for example, even when a large amount of exposure is required for exposure, it is possible to perform exposure while minimizing a decrease in processing capability. Further, a sufficient exposure amount can be obtained without increasing the size of the light source lamp or improving the transmittance of the optical member as in the related art.

Also, by changing only the width in the X direction of each of the projection areas P1 to P5, the amount of exposure can be increased or decreased without changing the width in the Y direction. Exposure can be performed without narrowing the transfer area, thereby obtaining excellent productivity.

The projection area changing mechanism 11 can change the exposure width of each of the projection areas P1 to P5 only by moving the light shielding member 12, and the structure including the driving mechanism 13 is simple and small. The size of the exposure apparatus does not increase, and the manufacturing cost can be reduced. Further, there are advantages such as easy maintenance.

Changing the exposure width changes the width in the Y direction of the overlapped exposure area provided in both projection areas in order to perform overlapped exposure between adjacent projection areas. It is also possible to widen the overlapping exposure area to relax the relative transfer image position accuracy between the adjacent projection optical systems 3A to 3E. As a result, the allowable range of the fluctuation of the transfer image position generated on the optical member due to the continuous exposure for a long time is extended, so that the frequency of performing the operation of adjusting the connection state between the optical members is reduced, and the maintenance of the exposure apparatus during a certain period is reduced. The required time can be shortened, and the operating time of the exposure apparatus can be extended. In addition, it is possible to increase the scanning speed by increasing the exposure width, and this shortens the exposure time required for one exposure, so that the fluctuation of the transfer image position due to one exposure can be suppressed. Further, the productivity can be improved by changing the exposure width.

Further, even during one exposure, it is possible to select the performance to be prioritized by controlling the driving mechanism 13 to change the exposure width. For example, even during the exposure in which the processing capability is prioritized, in a portion where the photoresist layer tends to be thick, such as the peripheral portion of the glass plate 4,
While maintaining the scanning speed constant, each projection area is enlarged from P1 to P5 to increase the amount of exposure, so that accurate exposure processing can be performed without lowering the processing ability, and the peripheral portion caused by peeling of the photoresist layer. Of the pattern can be prevented.

In the present embodiment, the projection area changing mechanism 11 is composed of the light shielding member 12 and the driving mechanism 13. However, for example, the field stop 8 is constituted by a liquid crystal substrate which transmits light on the front and back. Alternatively, the slits S1 to S5 whose exposure width can be freely changed may be formed by liquid crystal display.

In the present embodiment, a so-called multi-lens type scanning exposure apparatus using a catadioptric optical system has been described. However, the exposure apparatus according to the present invention is not limited to the catadioptric optical system, and the exposure light is not limited to the catadioptric optical system. What is necessary is just to set a plurality. Further, the exposure apparatus described in the present embodiment is of a type including five projection optical systems, but the number of projection optical systems is not limited.

The application of the scanning type exposure apparatus of the present embodiment is not limited to the exposure apparatus for manufacturing a liquid crystal display substrate, but can be widely used as an exposure apparatus for manufacturing, for example, a semiconductor or a thin film magnetic head.

[0051]

As described above, according to the scanning exposure apparatus of the first aspect of the present invention, the shape of the stop mechanism is changed, and each projection area projected on the photosensitive substrate is enlarged / reduced. By doing so, it is possible to increase or decrease the amount of exposure even while keeping the scanning speed constant. In addition, even if exposure is performed with the same exposure amount, the processing capacity can be improved by enlarging each projection area and increasing the scanning speed, or the processing speed cannot be reduced but the projection speed is reduced by reducing each projection area. It is possible to improve the optical accuracy by lowering. Thus, for example, even when a large amount of exposure is required for exposure, exposure can be performed while minimizing a decrease in processing capability. Further, a sufficient exposure amount can be obtained without increasing the size of the light source lamp or improving the transmittance of the optical member as in the related art. Further, by controlling the width of the aperture mechanism in accordance with the change in the scanning speed of the exposure light, it is possible to select the performance to be prioritized even during the exposure, whereby the transfer area that can be processed by one exposure By selecting the performance to be prioritized for each part, it is possible to achieve both the processing performance and the optical accuracy.

According to the scanning exposure apparatus of the second aspect,
The width of the aperture mechanism is determined based on the tolerance of the pattern transfer position error, so that the exposure process is performed with priority on either the processing capability or the optical accuracy while maintaining the optical accuracy within the allowable range. Can be implemented.

According to the scanning exposure apparatus of the third aspect,
By expanding / reducing the width of the aperture mechanism according to the acceleration / deceleration of the scanning speed performed during exposure, a constant exposure amount can be secured even when the scanning speed changes.

According to the scanning exposure apparatus of the fourth aspect,
Since the acceleration / deceleration of the scanning speed is acceleration until reaching the scanning speed at the start of exposure, or deceleration from the scanning speed at the end of exposure, the acceleration / deceleration of the scanning speed which cannot be avoided at the start and end of exposure Without making a problem, a constant exposure amount can be ensured from the start to the end of the exposure, thereby preventing a decrease in optical accuracy.

According to the scanning exposure apparatus of the fifth aspect,
The projection area changing means can enlarge / reduce each projection area only by moving the light shielding member, and its structure including the driving mechanism is simple and small, so that the size of the apparatus itself can be increased. In addition, it is possible to keep the manufacturing cost low. Further, there are advantages such as easy maintenance.

According to the scanning exposure apparatus of the sixth aspect,
By enlarging / reducing the overlapping exposure area between adjacent projection areas in accordance with the enlargement / reduction of the projection area, it is possible to adjust the positional accuracy between adjacent projection optical systems.
As a result, the allowable range of the variation of the transfer image position generated on the optical member due to the continuous exposure for a long time is expanded, so that the frequency of performing the operation of adjusting the connection state between the optical members is reduced, and the maintenance of the exposure apparatus during a certain period is reduced. The required time can be shortened, and the operating time of the exposure apparatus can be extended.

[Brief description of the drawings]

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

FIG. 2 is a plan view of the field stop shown in FIG.

FIG. 3 is a side view of the projection optical system shown in FIG.

4 is a plan view of the projection area changing mechanism shown in FIG.

5 is a sectional view taken along line VV in FIG.

FIG. 6 is a plan view showing an arrangement of a light shielding member for each slit when a projection area is enlarged.

FIG. 7 is a plan view showing an arrangement of a light shielding member for each slit when the projection area is reduced.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mask 3A-3E Projection optical system 4 Glass plate (substrate) 8 Field stop 11A, 11B Projection area change mechanism (aperture control mechanism) 12 Shielding member 13 Drive mechanism L Illumination optical system AX1-AX5 Optical axis M1-M5 Illumination area S1 -S5 Slit (aperture mechanism) P1-P5 Projection area

Claims (6)

[Claims] A light source unit; an illumination optical system for illuminating a plurality of portions of a mask having a pattern with a light beam from the light source unit; a plurality of projection optical systems for projecting the pattern on a substrate having a photosensitive layer; A plurality of aperture mechanisms arranged at positions substantially optically conjugate to the mask and for limiting the pattern projected onto the substrate for each of the plurality of projection optical systems; and an aperture control mechanism for changing the shape of the aperture mechanism And a scanning mechanism for scanning the mask and the substrate in synchronization with each other, wherein the aperture control mechanism controls the widths of the plurality of aperture mechanisms in a scanning direction of the mask and the substrate according to a scanning speed. A scanning exposure apparatus characterized by the above-mentioned. 2. The scanning exposure apparatus according to claim 1, wherein the width of the aperture mechanism is determined based on a tolerance of a transfer position error of the pattern. 3. The scanning exposure according to claim 1, wherein the aperture control mechanism expands / contracts the width of the aperture mechanism in accordance with acceleration / deceleration of the scanning speed performed during exposure. apparatus. 4. The scanning type according to claim 3, wherein the acceleration / deceleration of the scanning speed is acceleration until reaching the scanning speed at the start of exposure or deceleration from the scanning speed at the end of exposure. Exposure equipment. 5. The aperture control mechanism according to claim 1, further comprising: a light-shielding member movably supported in the scanning direction; and a driving mechanism for driving the light-shielding member in the scanning direction. 5. The scanning exposure apparatus according to claim 3 or 4. 6. A pattern image projected onto the substrate has, in part, a superimposed exposure region in which superimposed exposure is performed between adjacent pattern images, and the aperture control mechanism increases the width of the plurality of aperture mechanisms. /
6. The scanning exposure apparatus according to claim 1, wherein the overlapping exposure area is enlarged / reduced in accordance with the reduction.