Projection exposure apparatus

Abstract

Constant speed drive of a reticle and a wafer in a relative scanning direction and positioning of the reticle and the wafer are simultaneously performed with high precision by a slit scanning exposure scheme. A reticle side scanning stage for scanning a reticle relative to a slit-like illumination area in the relative scanning direction is placed on a reticle side base. A reticle side fine adjustment stage for moving and rotating the reticle within a two-dimensional plane is placed on the reticle side scanning stage. The reticle is placed on the reticle side fine adjustment stage. Constant speed drive and positioning of the reticle and a wafer are performed by independently controlling the reticle side scanning stage and the reticle side fine adjustment stage.

Description

Therefore, the acceleration b is lower than the acceleration a, and positional control of the reticle side fine adjustment stage 21 hardly affects the constant speed scanning operation of the reticle side scanning stage 20, thus realizing stable speed control.

A projection exposure apparatus according to the second embodiment of the present invention will be described next with reference to FIGS. 6 to 16B. In this embodiment, the present invention is applied to a projection exposure apparatus of a stitching and slit scanning exposure scheme, which apparatus includes a pulse emission type laser source.

FIG. 6 shows the overall arrangement of the projection exposure apparatus of the second embodiment. The second embodiment has almost the same arrangement as that of the first embodiment except for the illumination optical system 22 and the stage system for a reticle in the first embodiment. Therefore, the same reference numerals in FIG. 6 denote the parts having the same functions as in FIG. 1, and a description thereof will be omitted.

Referring to FIG. 6, a laser beam LB emitted from a pulse laser source 52 such as an excimer laser is incident on an illumination optimizing optical system 53 constituted by a beam expander an optical integrator, and an aperture stop, a relay lens, and the like. A pulse laser beam IL as exposure light emerging from the illumination optimizing optical system 53 is reflected by a deflecting mirror 54 to be incident on a field stop 55. The pulse laser beam IL passing through the aperture of the field stop 55 illuminates a reticle 7 with uniform illuminance through a relay lens 56, a deflecting mirror 57, and a condenser lens 58. The plane where the field stop 55 is arranged is conjugate to the pattern formation surface of the reticle 7. The shape of a slit-like illumination area 43 on the pattern formation surface of the reticle 7 is set by the aperture of the field stop 55.

The reticle 7 is held on a reticle stage 61. Movable mirrors 62 are attached to the reticle stage 61 in the X direction (a lateral direction parallel to the drawing surface of FIG. 6) and the Y direction (a direction perpendicular to the drawing surface of FIG. 6), respectively. The reticle stage 61 and the movable mirrors 62 are held such that they can be moved along a guide 63 with the X—Y plane and can be moved in the X direction at a constant speed. A drive 66 is connected to the reticle stage 61 to move the stage 61 in the X and Y directions and perform fine rotation for yawing correction. Laser beams from a laser interferometer 64 fixed to the guide 63 are reflected by the movable mirrors 62 so that the X- and Y-direction positions of the reticle 7 and its yawing amount are constantly measured by the laser interferometer 64. The measurement data are supplied to a main control system 23. The main control system 23 supplies a control signal S₁ to the drive 66 to control the movement of the reticle 7, and also outputs a control signal S₂ to a laser source control system 51 to control the emission of the pulse laser source 52. The main control system 23 includes a storage unit 23a.

FIG. 7A shows the slit-like rectangular illumination area 43 on the reticle 7. The illumination area 43 is inscribed in the contour of a circular area conjugate to the maximum exposure field of a projection optical system 13. The illumination area 43 has a length LP (=L+2M) in the Y direction and a width D in the X direction. When the reticle 7 is scanned in the X direction, a pulse laser beam within the illumination area 43 sequentially illuminates a pattern area wider than the illumination area 43 on the reticle 7. As shown in FIG. 7B, according to a light intensity distribution (to be referred to as an illuminance distribution hereinafter) S in the Y direction within the illumination area 43, the light intensity is constant in a central area having a length L, and decreases almost linearly to 0 in side areas 43a and 43b, each having a length M. That is, the illuminance distribution S of the illumination area 43 in the Y direction perpendicular to the relative scanning direction has a trapezoidal shape. In order to obtain such a trapezoidal illuminance distribution, the aperture of the field stop 55 in FIG. 6 may be set in a defocus state in the longitudinal direction. Alternatively, a trapezoidal illuminance distribution can be obtained by arranging an ND filter plate or the like, whose transmittance linearly changes, in the field stop 55 or the illumination optimizing optical system 53.

FIG. 8 shows the reticle 7 in FIG. 6. Referring to FIG. 8, a pattern area 75 having a width LT in the Y direction is formed on the pattern formation surface of the reticle 7. A circuit pattern to be transferred onto a wafer is formed in this pattern area 75. A forbidden zone 76, consisting of a light-shielding portion having a width M or more, is formed on outer peripheral portions of the pattern area 75 in the Y direction. In the second embodiment, the pattern area 75 is scanned twice in the X direction with the slit-like illumination area 43 to transfer a pattern of the pattern area 75 onto the wafer. For example, a pattern of a substantially right half area 75a is transferred onto the wafer by the first scanning operation, and a pattern of a substantially left half area 75b is transferred onto the wafer by the second scanning operation.

In this case, a left side portion of the area 75a and a right side portion of the area 75b are superposed on each other at a connection area 75c having the width M in the Y direction, and the connection portion 75c is scanned by the area 43a or 43b in which the light intensity (illuminance) of the illumination area 43 gradually decreases. With this operation, the illuminance distribution of the connection portion 75c is made uniform, and the position deviation of a transferred pattern can be prevented. In addition, in order to make the illuminance in the pattern area 75 constant, no area at an end portion of the pattern area 75 in the Y direction is scanned by the area 43a or 43b in which the illuminance of the illumination area 43 gradually decreases. Since the Y-direction width of the area, in the illumination area 43, in which the illuminance is constant is represented by L, and the Y direction width of the pattern area 75 is represented by LT, the Y-direction width M of the area 43a or 43b in which the illuminance gradually decreases to 0 is given by:
M=LT−2·L   (2)

In general, the pattern area 75 is scanned n times in the X direction by the illumination area 43 to transfer a pattern of the pattern area 75 onto a wafer 14. In order to prevent the formation of an area which is illuminated only with the area 43a or 43b in which the illuminance gradually decreases, the width M of the area 43a or 43b in which the illuminance gradually decreases may be set as follows:
M=(n·LP−LT)/(n+1)   (3)

FIG. 9A shows a slit-like rectangular exposure area 43 P on the wafer 14 in FIG. 6. The exposure area 43 P is conjugate to the illumination area 43 on the reticle 7 in FIG. 7A. In this case, since the projecting magnification of the projection optical system 13 is β, the X- and Y-direction widths of the exposure area 43 P are β·D and β·LP, respectively. In addition, as shown in FIG. 9B, in areas 43 aP and 43 bP, of the exposure area 43 P, located at two ends and having a width β·M in the Y direction, illuminance S decreases almost linearly to 0. The illuminance distribution of the exposure area 43 P in the Y direction perpendicular to the relative scanning direction has a trapezoidal shape.

The condition for the width β·D of the exposure area 43 P in the X direction as the relative scanning direction will be described next. In this case, provided that the pulse emission period (i.e., the reciprocal of an emission frequency f) of the pulse laser source 52 in FIG. 6 is T, and the distance by which the wafer 14 is scanned in the X direction in one period T during an slit scanning exposure operation is ΔL, the X-direction width Δ·D of the exposure area 43 P is set to be an integer multiple of the distance ΔL. In addition, if the scanning speed of the wafer 14 in the X direction is represented by V, then the distance ΔL is T·V. That is, the following equation can be established, providing that m is an integer of one or more:
β·D=m·ΔL=m·T·V   (4)

FIG. 9A shows a case where β·D=4·ΔL. In this case, for example, an exposure point Q0 which is present at an edge portion of the exposure area 43 P when pulse emission occurs is irradiated with a pulse laser beam corresponding to three pulses within the exposure area 43 P, and is irradiated with a pulse laser beam corresponding to two pulses at the edge portion of the exposure area 43 P. Letting ΔE be the energy radiated on an exposure point inside the exposure area 43 P by one pulse emitting operation, energy represented by 4·ΔE (=ΔE/2+3·ΔE+ΔE/2) is radiated on the exposure point Q0. In addition, as shown in FIG. 9A, energy represented by 4·ΔE is radiated on an exposure point Q1, on the wafer, which is present inside the edge portion of the exposure area 43 P when pulse emission occurs, and energy represented by 4·ΔE is radiated on an exposure point Q2, on the wafer, which is present outside the edge portion of the exposure area 43 P when the pulse emission occurs. As described above, according to the second embodiment, the same pulse laser beam corresponding to m pulses is radiated on all the exposure points, on the wafer, which are scanned by the exposure area 43 P. Therefore, a constant illuminance distribution is set at the exposure points which are scanned by the area, of the exposure area 43 P, in which the illuminance is constant.

Although energy corresponding to m pulses is radiated on exposure points which are scanned once by the two side areas 43 aP and 43 bP of the exposure area 43 P, the radiated energy is lower than that radiated on the other exposure points. However, as described above, in the second embodiment, since a connection portion is scanned twice by the areas 43 aP and 43 bP in a stitching operation, energy represented by m·ΔE is also radiated on each exposure point of the connection portion. Therefore, the same amount of energy is radiated on all the exposure points on the wafer, preventing illuminance irregularity.

An example of stitching and slit scanning exposure in the second embodiment will be described next. Referring to FIG. 6, while the slit-like illumination area 43 on the reticle 7 is illuminated with the pulse laser beam IL, the main control system 23 scans the reticle 7 in the −X direction at the constant speed V/β through the drive 66 and the reticle stage 61. In synchronism with this scanning operation, the main control system 23 scans the wafer 14 in the X direction at the constant speed V through a drive 31. In this case, the main control system 23 obtains the coordinate position (RSx,RSy) of the reticle 7 and the coordinate position (WSx,WSy) of the wafer 14 at the time when, for example, a predetermined alignment mark on the reticle 7 coincides with a predetermined alignment mark on the wafer 14, on the basis of measurement values obtained by a laser interferometer 64 and a laser interferometer 47. Similar to the first embodiment, the main control system 23 then calculates (SWx/β+RSx), (WSy/β+RSy), and (WSθ+RSθ), and stores these values as reference values in the storage unit 23a in advance. In addition, the main control system 23 obtains these three reference value for each shot exposed on the wafer in advance, and stores them in the storage unit 23a. The main control system 23 controls the coordinate positions of the wafer 14 and the reticle 7 through the drives 66 and 31 such that the three data (WSx/β+RSx), (WSy/β+RSy), and (WSθ+RSθ) sampled during a relative scanning operation with respect to the wafer 14 and the reticle 7 coincide with the above-mentioned reference values.

With this operation, as shown in FIG. 8, on the reticle 7 side, the slit-like illumination area 43 relatively scans the right area 75a of the pattern area 75 along a trace 77. In addition, as shown in FIG. 10A, on the wafer side 28, the slit-like exposure area 43 P relatively scans a left area 80a of an exposure area 80 along a trace 77 P.

When the first slit scanning exposure operation is completed, the reticle 7 is moved in the Y direction by stitching so as to move the illumination area 43 to an upper left position in the pattern area 75 along a trace 78, as shown in FIG. 8. Referring to FIG. 10A, a slit-like exposure area 20 P is moved to a lower right position in the exposure area 80 along a trace 78 P by moving the wafer 14 in the −Y direction. Thereafter, the reticle 7 is scanned at the speed V/β in the X direction, and the wafer 14 is scanned at the speed V in the −X direction, thereby performing the second slit scanning exposure operation. As a result, as shown in FIG. 8, on the reticle 7 side, the slit-like illumination area 43 relatively scans the left area 75b of the pattern area 75 along a trace 79. In addition, as shown in FIG. 10A, on the wafer 14 side, the slit-like exposure area 43 P relatively scans the right area 80b of the exposure area 80 along a trace 79 P.

As shown in FIG. 8, at the connection portion 75c of the pattern area 75 of the reticle 7, exposure is performed twice by the left and right areas 43a and 43b, of the illumination area 43, in which the illuminance decreases, with the first and second scanning operations. Therefore, the main control system 23 controls the position of the reticle 7 such that the moving amount of the reticle 7 in the Y direction in a stitching operation becomes (LP−M). Similarly, the main control system 23 controls the position of the wafer 14 such that the moving amount of the wafer 14 in the −Y direction in a stitching operation becomes (LP−M)/β.

With this control, as shown in FIG. 10A, at a connection portion 80c, of the exposure area 80 of the wafer 14, located at a middle position in the Y direction, exposure is performed twice by the right and left areas 43 ap and 43 bp, of the slit-like exposure area 43 P, in which the illuminance decreases. For example, at an exposure point Q3 inside the connection portion 80c, the illuminance in the first exposure operation becomes an illuminance SA in FIG. 10B; and the illuminance in the second exposure operation, an illuminance SB. As shown in FIG. 9B, since the illuminances of the areas 43 aP and 43 bP in the Y direction symmetrically and linearly decrease to 0, the sum of the illuminances SA and SB in FIG. 10B becomes equal to an illuminance SC obtained when exposure is performed by using the area, of the exposure area 43 P, in which the illuminance is constant.

As has been described above, all the exposure points which are scanned by the exposure area 43 P once are irradiated with a pulse laser corresponding to m pulses. The exposure point Q3 inside the connection portion 80c is irradiated with the same amount of energy as that radiated on an exposure point which is scanned once by two scanning operations of the exposure area 43 P (i.e., an exposure point outside the connection portion). Therefore, the illuminances at all the exposure points on the wafer 14 are made uniform. In addition, at an exposure point inside the connection portion 80c, the number of pulses radiated in two scanning operations is 2 m, which is twice that radiated at an exposure point outside the connection portion. Therefore, at the connection portion 80c, especially variations in the energy of a pulse laser beam for each pulse and the influences of speckles are reduced. More specifically, at the connection portion 80c, the variations in illuminance due to variations in the energy of a pulse laser beam for each pulse are reduced to ½^1/2 the variations at a non-connection portion.

In the second embodiment, when slit scanning exposure is to be performed with respect to the area 80a on the wafer 14 shown in FIG. 10A, the main control system 23 stores the differences between the above-mentioned three data (WSx/β+RSx), (WSy/β+RSy), and (WSθ+RSθ) and the corresponding reference values in the storage unit 23a. When a pulse laser beam corresponding to m pulses is radiated on an arbitrary exposure point on the wafer 14 by the first scanning operation, the main control system 23 monitors each difference in synchronism with each pulse emitting operation. These differences cause intra-shot distortion at the connection portion 80c on the wafer 14. Therefore, when exposure is to be performed with respect to the area 80b on the wafer 14 by the second scanning operation, the main control system 23 controls the coordinate positions of the reticle 7 and the wafer 14 through the drives 66 and 31 such that the monitored differences coincide with the readout differences. With this operation, the pattern overlapping precision at the connection portion 80c on the wafer 14 is greatly improved.

In general, if the positioning precisions of the reticle stage 61 and wafer stages (27 and 28) in the X and Y directions are respectively represented by Δx and Δy, overlapping errors at the connection portion 80c are respectively represented by 2^1/2Δx and 2^1/2Δy. In contrast to this, according to the method of the second embodiment, the overlapping errors are only Δx and Δy because the positions of the reticle 7 and the wafer 14 in exposing the area 80b by the second scanning operation are controlled in accordance with shot distortion caused in exposing the area 80a by the first scanning operation.

A method of exposing the entire exposure surface of the wafer 14 will be described next. Consider a case where the stitching and slit scanning exposure operation described in the second embodiment is applied to this exposure method. As shown in FIG. 11, exposure is sequentially performed with respect to adjacent areas 80-1a, 80-1b, 80-2a, 80-2b, . . . , 80-4a, and 80-4b by the slit scanning exposure method. According to this scanning method, a pattern of the pattern area 75 can be transferred onto the wafer 14 in a short period of time, and hence the transfer operation is not easily influenced by the expansion of the wafer 14 and the like. In contrast to this, the precision at the connection portion may deteriorate depending on the characteristics in the scanning direction. For this reason, the reticle 7 must be moved, along the trace 78, in the Y direction with respect to the illumination area 43 in FIG. 8, at a high speed.

According to another exposure method, as shown in FIGS. 12A and 12B, for example, only the right half area 75a of the pattern area 75 of the reticle 7 is continuously exposed on a corresponding area on the wafer 14. Thereafter, only the left half area 75b of the pattern area 75 is continuously exposed on a corresponding area on the wafer 14. In this method, as shown in FIG. 12A, exposure is performed first with respect to the areas 80-1a, 80-2a, . . . , 80-4a on the wafer 14. Thereafter, as shown in FIG. 12B, exposure is performed with respect to the areas 80-1b, 80-2b, . . . , 80-4b on the wafer 14 along a trace parallel to the trace in FIG. 12A. Therefore, the main control system 23 controls the position of the wafer 14 such that the moving amount of the wafer 14 corresponding to the trace 78 P of the exposure area 43 P in the −Y direction in FIG. 10A becomes 2(LP−M)/β. According to this method, in two exposure areas (e.g., the areas 80-1a and 80-1b), on the wafer 14, corresponding to the pattern area 75 of the reticle 7, the slit-like exposure area 43 P is scanned in the same relative scanning direction. With this operation, the overlapping precision at the connection portion 80c is improved.

In the first and second embodiments, since a refracting optical system is used as the projection optical system 13, a rectangular illumination area is set on the reticle 7, as shown in FIGS. 5A and 7A. In contrast to this, the use of a projection optical system constituted by a reflecting/refracting optical system using a concave mirror and the like will provide advantageous effects in terms of aberrations and the like, especially as the wavelength of exposure light decreases. If this reflecting/refracting optical system is used, since the aberrations of a concave mirror or the like are reduced as the distance from the optical axis increases, the slit-like illumination area on the reticle 7 becomes an arcuated illumination area 81, as shown in FIG. 13A.

Assume that a width D of the illumination area 81 in the relative scanning direction is constant, and that the longitudinal direction, of the illumination area 81, which is perpendicular to the relative scanning direction is defined as the Y direction. In this case, the Y-direction illuminance distribution of the illumination area 81 is set to be trapezoidal, as shown in FIG. 13B. That is, in two sides areas 81a and 81b of the illumination area 81 in the Y direction, the illuminances linearly decrease to 0. By setting such as illuminance distribution, the illuminance irregularity at the connection portion in a stitching operation can be reduced, similar to the second embodiment described above.

Consider a case where a regular hexagonal illumination area is set, as a modification of the second embodiment described above. The arrangement of this modification is the same as that of the second embodiment except for the shape of an illumination area.

In the modification, in the first and second wafer scanning operations, the wafer is set at the same X-direction position when a pulse laser source performs pulse emission. More specifically, as shown in FIG. 16A, the X-direction positions of an exposure point P9 which are set when pulse emission is performed in the first wafer scanning operation are defined as positions 8, and the X-direction positions of an exposure point P9 which are set when pulse emission is performed in the second wafer scanning operation are defined as positions 12. In this case, a main control system 23 controls the timing of pulse emission through a laser source control system 51 to make the positions 12 and 8 coincide with each other. As shown in FIG. 16A, there are five positions 8 inside an area 3a, and three positions 12 inside an area 3b. Therefore, with the two slit scanning exposure operations, energy corresponding to a total of eight pulses is radiated on the exposure point P9.

FIG. 16B shows a case where the pulse emission timings in the first and second scanning operations are shifted from those in the case shown in FIG. 16A in the X-direction by ΔL/2. Referring to FIG. 16B, assume that the X-direction positions of an exposure point P9 which are set when pulse emission is performed in the first wafer scanning operation are defined as positions 10, and the X-direction positions of the exposure point P9 which are set when pulse emission is performed in the second wafer scanning operation are defined as positions 13. In this case, the wafer is also set at the same X-direction position when the pulse laser source performs pulse emission in the first and second wafer scanning operations. Since there are four positions 10 in an area 3a, and four positions 13 in an area 3b, energy corresponding to eight pulses is radiated on the exposure point P9 by the two slit scanning exposure operations. In general, according to this modification, energy corresponding to eight pulses is radiated on each exposure point in a connection portion 4 as well as an exposure point P0 in a non-connection portion, thereby preventing illuminance irregularity.

Furthermore, in the modification, the pulse emission timing is controlled such that a wafer is set at the same X direction position when the pulse laser source performs pulse emission in the first and second scanning operations. However, a wafer side, X stage 27 may be controlled.

In the second embodiment and its modification, a stitching operation using one reticle has been described. However, a plurality of reticles may be placed on the same reticle stage, and scanning exposure may be repeatedly performed while the reticles are interchanged with each other in a stitching operation. In addition, the reticle stage in the second embodiment and its modification may be constituted by a reticle side scanning stage and a reticle side fine adjustment stage, as in the case of the reticle stage system in the first embodiment.

The present invention is not limited to the first and second embodiments described above, and various changes and modifications can be made without departing from the scope and spirit of the invention.

Claims

1. An exposure apparatus for radiating exposure light on a predetermined illumination area on a mask on which a pattern to be transferred is formed, and exposing the pattern on a photosensitive substrate, comprising:

a scanning system for synchronously scanning the mask and the photosensitive substrate in a predetermined first direction of the illumination area while maintaining a predetermined speed ratio; and

an illumination condition setting portion for setting the illumination area to be rectangular, and letting a light intensity distribution of the illumination area in a second direction substantially perpendicular to the first direction have a trapezoidal shape so that a middle portion of the distribution exhibits a substantially constant light intensity, and two side portions of the distribution exhibit a gradually decreasing light intensity.

2. An apparatus according to claim 1, wherein said scanning system scans the mask and the photosensitive substrate at least twice in the first direction, and further comprising a substrate moving system for moving the photosensitive substrate in the second direction while first and second scanning operations with respect to the mask and the photosensitive substrate are performed by said scanning system.

3. An apparatus according to claim 2, further comprising a mask moving system for moving the mask in the second direction while first and second scanning operations with respect to the mask and the photosensitive substrate are performed by said scanning system.

4. An apparatus according to claim 2, further comprising:

storage portion for storing a relative positional difference between the mask and the photosensitive substrate when the mask and the photosensitive substrate are to be synchronously scanned in the first direction; and

a controller for controlling a position of at least of one of the mask and the photosensitive substrate such that the relative positional difference in the first scanning operation with respect to the mask and the photosensitive substrate coincides with that in the second scanning operation.

5. An apparatus according to claim 2 wherein said illumination condition setting portion determines a length M of each of the side portions, of the illumination area, in which the light intensity gradually decreases, in the second direction so as to establish

M=(n·LP−LT)/(n+1)

6. An apparatus according to claim 5, further comprising a projection optical system for projecting an image of a pattern of the mask, irradiated with the exposure light, onto the photosensitive substrate at a projecting magnification β, and wherein a moving amount of the photosensitive substrate moved by said substrate moving system in the second direction is defined as

n·(LP−M)/β

7. A projection exposure apparatus comprising:

a pulse light source for pulse-emitting exposure light;

an illumination optical system for illuminating a predetermined illumination area on a mask, on which a pattern to be transferred is formed, with the exposure light;

a projection optical system for projecting an image of the pattern, irradiated with the exposure light, onto a photosensitive substrate;

a scanning system for synchronously scanning the mask and the photosensitive substrate at least twice in a predetermined first direction of the illumination area while maintaining a predetermined speed ratio;

a substrate moving system for moving the photosensitive substrate in a second direction substantially perpendicular to the first direction while first and second scanning operations with respect to the mask and the photosensitive substrate are performed by said scanning system; and

a controller for controlling at least one of said pulse light source and said scanning system such that a position of the photosensitive substrate in the first direction at the time when said pulse light source performs pulse emission, in the first scanning operation with respect to the photosensitive substrate and the mask coincides with that in the second scanning operation.

8. An apparatus according to claim 7, wherein said controller includes a position storage portion for detecting a position of the photosensitive substrate in the first direction when said pulse light source performs pulse emission, and storing data indicating the position, and controls one of said pulse light source and said synchronous scanning means on the basis of the stored data indicating the position of the photosensitive substrate.

9. A scanning exposure apparatus comprising:

a scanning system for synchronously scanning a mask and a photosensitive substrate for scanning exposure; and

an adjusting system for moving the mask to decrease a positional deviation between the mask and the substrate, independently of scanning of the mask which is performed by said scanning system, during the scanning exposure.

10. An apparatus according to claim 9, further comprising:

a projection optical system for projecting a pattern image of the mask onto the substrate; and wherein

said scanning system includes a mask stage for scanning the mask in a direction perpendicular to an optical axis of said projection optical system and a substrate stage for scanning the substrate in the direction perpendicular to the optical axis, and causes the mask stage and the substrate stage to scan at a speed ratio corresponding to a projecting magnification of said projection optical system.

11. An apparatus according to claim 10, wherein

said adjusting system includes a finely movable stage for relatively moving the mask on said mask stage and a driving member for finely driving said finely movable stage in the direction perpendicular to said optical axis.

12. An apparatus according to claim 11, further comprising:

a first measuring system for measuring a position of the mask within a plane perpendicular to said optical axis; and

a second measuring system for measuring a position of the substrate within a plane perpendicular to said optical axis, and wherein

said adjusting system includes a controller for controlling the driving member in accordance with signals from said first and second measuring systems.

13. An apparatus according to claim 12, wherein

said first measuring system includes a rotational angle detecting device for detecting a rotational angle of the mask within the plane perpendicular to said optical axis.

14. An apparatus according to claim 13, wherein

said finely movable stage includes a mirror having a reflecting surface substantially perpendicular to said plane, and

said first measuring system includes an interferometer for radiating a light beam onto said reflecting surface and receiving the light beam reflected by said reflecting surface.

15. A scanning exposure apparatus for projecting a pattern image of a mask onto a sensitive plate through a projection optical system in a scanning manner, the exposure apparatus comprising:

(a) a plate stage for scanning the plate in at least one-dimensional direction under said projection optical system for the scanning exposure;

(b) a first mask stage for scanning the mask in at least said one-dimensional direction above said projection optical system for the scanning exposure;

(c) a second mask stage for finely moving the mask on said first mask stage in each of translational and rotational directions;

(d) a first driving system for synchronously driving said plate stage and said first mask stage with a predetermined velocity ratio for the scanning exposure;

(e) a detecting system for detecting a positional deviation amount between the mask and the plate in a real time manner during the scanning exposure; and

(f) a second driving system for driving said second mask stage to decrease the detected deviation amount during the scanning exposure.

16. The scanning exposure apparatus according to claim 15, wherein said detecting system includes a first measuring unit to detect a relative translational deviation amount between the mask and the plate and a second measuring unit to detect a relative rotational deviation amount between the mask and the plate.

17. The scanning exposure apparatus according to claim 16, wherein said second drive system includes a first actuator unit for finely moving said second mask stage in said one-dimensional scanning direction and in a cross direction of said scanning direction based on said translational deviation amount.

18. The scanning exposure apparatus according to claim 16, wherein said second drive system includes a second actuator unit for finely rotating said second mask stage about a predetermined point on the mask based on said rotational deviation amount.

19. The scanning exposure apparatus according to claim 18, wherein said predetermined point on the mask is changed in said one-dimensional scanning direction according to the scanning position of the mask.

20. The scanning exposure apparatus according to claim 16, wherein said first and second measuring units include a mask side interferometer system for measuring a coordinate position and a rotational angle of the mask and a plate side interferometer system for measuring a coordinate position and a rotational angle of the plate.

21. The scanning exposure apparatus according to claim 15, wherein each of said plate stage and said first mask stage is linearly movable in said one-dimensional scanning direction by restraining of respective linear air-guide structures.

22. The scanning exposure apparatus according to claim 21, wherein said first driving system includes a mask side linear motor for driving said first mask stage guided by the corresponding linear air-guide structure and a plate side linear motor for driving said plate stage guided by the corresponding linear air-guide structure.

23. A scanning exposure apparatus for projecting a pattern image of a mask onto a sensitive plate through a projection optical system in a scanning manner, the exposure apparatus comprising:

(a) a plate stage for moving the plate in at least one-dimensional direction under said projection optical system which has an imaging reduction ratio 1/β;

(b) a first mask stage for moving the mask in at least said one-dimensional direction above said projection optical system;

(c) a second mask stage for finely moving the mask on said first mask stage in each of translational and rotational direction;

(d) an illuminating system for irradiating the mask with a radiation having a slit shaped distribution elongated perpendicular to said one-dimensional direction on the mask in order to project a slit shaped partial pattern image of the mask onto the plate through said projection optical system;

(e) a first driving system for synchronously, relatively driving said plate stage and first mask stage with a velocity ratio B for the scanning exposure of the plate by said slit shaped partial pattern image of the mask;

(f) a detecting system for detecting a deviation amount from an ideal positional relation of the mask and the plate occurring at a term of the scanning exposure; and

(g) a second driving system for driving said second mask stage to correct the deviation during the scanning exposure when said detected deviation amount is out of a predetermined tolerance.

24. The scanning exposure apparatus according to claim 23, wherein said detecting system includes a first measuring system to detect a translational deviation amount from said ideal positional relation of the mask and the plate and a second measuring system to detect a rotational deviation amount from said ideal positional relation of the mask and the plate.

25. The scanning exposure apparatus according to claim 24, wherein said second drive system includes a first actuator system for finely moving said second mask stage in said one-dimensional scanning direction and a cross direction thereof based on said translational deviation amount.

26. The scanning exposure apparatus according to claim 24, wherein said second drive system includes a second actuator system for finely rotating said second mask stage about a predetermined point on the mask based on said rotational deviation amount.

27. The scanning exposure apparatus according to claim 26, wherein said predetermined point on the mask is changed in said one-dimensional scanning direction according to the scanning position of the mask.

28. The scanning exposure apparatus according to claim 23, wherein said first driving system includes a mask side linear motor for driving said first mask stage supported by an air-guide structure and a plate side linear motor for driving said plate stage supported by an air-guide structure.

29. A scanning exposure apparatus for projecting a pattern image of a mask onto a sensitive plate through a projection system having a predetermined magnification ratio in a scanning manner, the apparatus comprising:

(a) a scanning system for synchronously, relatively scanning the mask and the plate with respect to a projection field of said projection system at a velocity ratio corresponding to said magnification ratio during the scanning exposure;

(b) a finely movable stage provided on said scanning system for finely moving the mask relative to said scanning system in each of translational and rotational directions;

(c) a detecting system for detecting a positional deviation amount between an ideal positional relation and an actual positional relation of the mask and the plate during the scanning exposure; and

(d) a control system for driving said finely movable stage based on said detected deviation amount in order to decrease the positional deviation of the mask and the plate.

30. A scanning exposure method in which a pattern area of a mask is transferred onto a sensitive plate through a projection optical system in a scanning manner, the method comprising the steps of:

(a) irradiating the mask with a radiation having a slit shaped intensity distribution in order to project a slit image portion of said pattern area of the mask toward the plate through said projection optical system;

(b) synchrouously scanning each of the mask and the plate relative to said projection optical system in a scanning direction perpendicular to a longitudinal direction of said slit image portion at a predetermined velocity ratio by using a scanning mechanism for the scanning exposure;

(c) detecting a deviation value between an ideal positional relation and an actual positional relation of the mask and the plate at a term of the scanning exposure; and

(d) correcting a position of the mask determined by said scanning mechanism so as to decrease said detected deviation value by using a fine moving mechanism provided on said scanning mechanism at the term of the scanning exposure.

31. The scanning exposure method according to claim 30, wherein said detecting step includes detecting a relative rotational deviation between the mask and the plate and said fine moving mechanism finely rotates the mask to decrease said rotational deviation.

32. The scanning exposure method according to claim 31, wherein said relative rotational deviation is detected by using a mask side interferometer system and a plate side interferometer system.

33. A scanning exposure method in which a pattern area of a mask is transferred onto a sensitive plate through a projection system in a scanning manner, the method comprising the steps of:

(a) irradiating the mask with a radiation in order to project an image portion of said pattern area of the mask onto the plate through said projection system;

(b) synchronously scanning each of the mask and the plate relative to said projection system in a scanning direction at a predetermined velocity ratio by using a scanning mechanism for the scanning exposure;

(c) detecting a deviation between an ideal positional relation and an actual positional relation of the mask and the plate at a term of the scanning exposure; and

(d) correcting a position of the mask determined by said scanning mechanism for decreasing said detected deviation by using a fine moving mechanism provided on said scanning mechanism at the term of the scanning exposure.

34. A scanning exposure apparatus for projecting a pattern image of a mask onto a sensitive plate through a projection system in a scanning manner, the exposure apparatus comprising:

(a) a plate stage for moving the plate under said projection system in an X direction for the scanning exposure and in a Y direction perpendicular to the X direction;

(b) a first mask stage for moving the mask in the X direction for the scanning exposure above said projection system;

(c) a second mask stage for finely moving the mask on said first mask stage in each of translational and rotational directions;

(d) first driving means for synchronously driving each of said plate stage and said first mask stage with a predetermined velocity ratio in the X direction during the scanning exposure; and

(e) second driving means for driving said plate stage and said second mask stage to maintain a translational relation of the mask and plate in the Y direction and for driving said second mask stage to maintain a relative rotational relation of the mask and the plate, during the scanning exposure.

35. A scanning exposure method in which in synchronism with movement of a first object formed with a predetermined pattern a second object is moved, thereby exposing sequentially a plurality of defined regions on said second object, comprising:

effecting an exposure onto one of the plurality of the defined regions on said second object while moving said second object in a predetermined direction, and

after finishing the exposure, moving said second object in a direction perpendicular to said predetermined direction while moving said second object in a direction parallel to said predetermined direction.

36. A scanning exposure method in which in synchronism with movement of a first object formed with a predetermined pattern a second object is moved, thereby exposing sequentially a plurality of defined regions on said second object, comprising:

effecting an exposure onto one of the plurality of the defined regions on said second object while moving said second object in a predetermined direction, and

after finishing the exposure, accelerating said second object in a direction intersecting with said predetermined direction while decelerating said second object in said predetermined direction.

37. A scanning exposure method in which in synchronism with movement of a first object formed with a predetermined pattern a second object is moved, thereby exposing sequentially a plurality of defined regions on said second object, comprising:

a first step of effecting an exposure onto one of the plurality of defined regions on said second object while moving said second object in a predetermined direction,

a second step of decelerating said second object in said predetermined direction after finishing the exposure,

a third step of accelerating said second object in a reverse direction to said predetermined direction after said second step, and

a fourth step of accelerating and decelerating said second object in a direction intersecting with said predetermined direction during said second step and said third step.

38. A scanning exposure method in which in synchronism with movement of a first object formed with a predetermined pattern a second object is moved, thereby exposing sequentially a plurality of defined regions on said second object, comprising:

effecting an exposure onto one of the plurality of defined regions on said second object while moving said first object in a first direction and moving said second object in a second direction corresponding to said first direction, and

after finishing the exposure, moving said second object in a direction parallel and perpendicular to said second direction simultaneously while decelerating said first object in said first direction.

39. A scanning exposure method in which in synchronism with movement of a first object formed with a predetermined pattern a second object is moved, thereby exposing sequentially a plurality of defined regions on said second object, comprising:

a first step of effecting an exposure onto one of the plurality of defined regions on said second object while moving said first object in a first direction and moving said second object in a second direction corresponding to said first direction, and

a second step of decelerating said second object in said second direction after finishing the first step,

a third step of accelerating said second object in a reverse direction to said second direction after said second step, and

a fourth step of decelerating said first object and setting said first object to a reference position during said second step and said third step.

40. A scanning exposure method in which in synchronism with movement of a first object formed with a predetermined pattern a second object is moved, thereby exposing sequentially a plurality of defined regions on said second object, comprising:

effecting an exposure onto one of the plurality of defined regions on said second object while moving said second object in a predetermined direction, and

after finishing the exposure, starting accelerating said second object in a reverse direction to said predetermined direction for preparing a scanning exposure onto a next defined region while moving said second object in a direction intersecting with said predetermined direction.

41. A scanning type exposure apparatus in which in synchronism with moving a first object in a first direction, a second object is moved in a second direction, thereby exposing sequentially each of a plurality of defined regions on said second object, comprising:

a projection optical system which is disposed in an optical path of an exposure beam, said first object being provided on one side of the projection optical system, said second object being provided on the other side of the projection optical system, and an image of a pattern formed on said first object being projected onto said second object by the projection optical system;

a first movable stage which holds said first object, at least a part of the first movable stage being disposed on the one side of the projection optical system;

a second movable stage which holds said second object, at least a part of the second movable stage being disposed on the other side of the projection optical system;

a first interferometer system which outputs positional information of said first movable stage, the first interferometer system being optically connected to said first movable stage;

a second interferometer system which outputs positional information of said second movable stage, the second interferometer system being optically connected to said second movable stage;

a first drive mechanism, functionally connected to the first movable stage, which moves said first movable stage in said first direction;

a second drive mechanism, functionally connected to the second stage, which moves said second movable stage in said second direction; and

a controller functionally connected to said first interferometer system, said second interferometer system, said first drive mechanism and said second drive mechanism, which converts positional information in said second direction of said second movable stage outputted from said second interferometer system to first speed information and speed controls said second drive mechanism so that said first speed information may correspond to a constant speed v, and which converts positional information in said first direction of said first movable stage outputted from said first interferometer system to second speed information and speed controls said first drive mechanism so that said second speed information may correspond to a constant speed v/β, where β is a projection magnification of the image of the pattern on said first object projected by said projection optical system.