JP2000003870A - Method and device for scanning exposure and manufacture of device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transfer the pattern of a mask on a photosensitive substrate in high accuracy without decreasing throughput, by changing the detecting point used for adjusting the position relationship of the image surface of a projecting system and the second body among the detecting points in correspondence in the moving direction of the second body. SOLUTION: Among a plurality of detecting points 21 and 27, which are arranged for detecting the position information of a second body 10 with regard to the optical-axis direction of a projecting system during the movement of the second body 10, the detecting point used for adjusting the position relationship of the image surface of the projecting system and the second body 10 is changed in correspondence with the moving direction of the second body 10. Thus, even when the scanning direction of the second body 10 is changed, the part to be exposed on the second body 10 can be aligned into the side surface with high accuracy. Therefore, the mask pattern as the first body can be transferred on the photosensitive substrate as the second body 10 in high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of illuminating a rectangular or arcuate illumination area with, for example, exposure light and scanning the mask and photosensitive substrate in synchronism with the illumination area. The present invention relates to an exposure method suitable for being applied to a so-called slit scan exposure type exposure apparatus that exposes the light onto a photosensitive substrate.

[0002]

2. Description of the Related Art Conventionally, when a semiconductor device, a liquid crystal display device, a thin film magnetic head, or the like is manufactured by using photolithography technology, a photomask or a reticle (hereinafter, referred to as a "reticle") has been used.
A projection exposure apparatus that exposes a pattern of a “reticle” to a photosensitive substrate such as a wafer or a glass plate coated with a photoresist or the like via a projection optical system is used. Recently, one chip pattern or the like of a semiconductor element has been increasing in size, and a projection exposure apparatus is required to have a large area for exposing a pattern having a larger area on a reticle onto a photosensitive substrate.

Further, as the pattern of a semiconductor element or the like becomes finer, it is required to improve the resolution of the projection optical system. However, in order to improve the resolution of the projection optical system, the projection optical system must be improved. However, there is a problem that the exposure field cannot be made too large. In particular, when a catadioptric system is used as the projection optical system, the shape of the aberration-free exposure field may be an arc-shaped region.

In order to increase the area of the pattern to be transferred and to limit the exposure field of the projection optical system, for example, a rectangular, arcuate or hexagonal illumination area (this is called a "slit illumination area"). A so-called slit scan exposure type projection exposure apparatus for exposing a pattern having a larger area than the slit-shaped illumination area on the reticle onto the photosensitive substrate by synchronously scanning the reticle and the photosensitive substrate has been developed. I have. Generally, in a projection exposure apparatus, it is necessary to perform exposure in a state where the exposure surface of the photosensitive substrate is aligned with the image plane (best image formation plane) of the projection optical system.
Even in the projection exposure apparatus of the slit scan exposure method,
An auto-focus mechanism that adjusts the height (focus position) of the reference point of the exposure surface of the photosensitive substrate in the focus direction to the image surface, and an auto-focus mechanism that adjusts the average exposure surface of the photosensitive substrate parallel to the image surface And a leveling mechanism.

In a conventional auto-focus mechanism, the height of a photosensitive substrate at or near the center of an exposure field of a projection optical system is detected by a focus position detection means, and the height is used as the height of the image plane of the projection optical system. Sa (best focus position)
The height of the substrate stage on which the photosensitive substrate is mounted is controlled so as to adjust the height. Similarly, the conventional auto-leveling mechanism detects the average inclination of the exposure surface of the photosensitive substrate in the exposure field of the projection optical system by the inclination angle detection means, and adjusts the inclination to the inclination of the image plane of the projection optical system. That is, the inclination of the substrate stage is controlled.

[0006]

In the conventional auto focus mechanism, the detection point by the focus position detection means is set at or near the exposure center in the exposure field of the projection optical system. Due to the influence of the phase delay caused by the signal processing time, there is a disadvantage that the focusing of the photosensitive substrate (focusing) becomes inaccurate. That is, in the case of the slit scan exposure method, since the photosensitive substrate is scanned with respect to the exposure field of the projection optical system, based on the focus position of a certain exposure area detected at the exposure center in the exposure field. However, even if the height of the substrate stage is adjusted after a predetermined signal processing time, it is not always possible to perform accurate focusing because another exposure area is included in the exposure field. .

To prevent this, it is conceivable to reduce the feed speed of the substrate stage. However, if the feed speed of the substrate stage is reduced, there is a disadvantage that the exposure time becomes longer and the throughput decreases. Similarly, in the conventional auto-leveling mechanism, since the detection surface of the tilt angle detecting means is set in the exposure field of the projection optical system, it is affected by the phase delay caused by the signal processing time of the tilt angle detecting means. In addition, there is a disadvantage that leveling of the photosensitive substrate becomes inaccurate.

In view of the foregoing, the present invention provides a scanning exposure method capable of transferring a mask pattern onto a photosensitive substrate with high accuracy without reducing throughput when performing exposure with a slit scanning exposure type projection exposure apparatus. The purpose is to do. Still another object of the present invention is to provide a scanning exposure apparatus capable of performing such a scanning exposure method, and a device manufacturing method capable of manufacturing a device with high accuracy using the scanning exposure method.

[0009]

SUMMARY OF THE INVENTION A first scanning type exposure apparatus according to the present invention comprises a second scanning exposure apparatus for synchronizing the movement of a first object with respect to an exposure beam and the second scanning exposure apparatus with respect to an exposure beam passing through a projection system. In a scanning type exposure apparatus that scans and exposes a second object by moving the object, a plurality of positions capable of detecting position information of the second object in the optical axis direction of the projection system during movement of the second object. Detecting means having a detecting point; an image plane of the projection system based on a detection result of the detecting means;
Adjusting means for adjusting the positional relationship with the object, wherein the detecting point used to adjust the positional relationship between the image plane of the projection system and the second object among the plurality of detecting points is set to the second point. This is changed according to the moving direction of the object.

Further, the second scanning type exposure apparatus according to the present invention moves the second object with respect to the exposure beam passing through the projection system in synchronization with the movement of the first object with respect to the exposure beam. Thereby, the scanning type exposure apparatus that scans and exposes the second object has a plurality of detection points capable of detecting the position information of the second object in the optical axis direction of the projection system while the second object is moving. Detecting means, and adjusting means for adjusting the positional relationship between the image plane of the projection system and the second object based on the detection result of the detecting means, and selectively using some of the plurality of detection points Then, the positional relationship between the image plane of the projection system and the second object is adjusted.

Next, in the first scanning exposure method according to the present invention, the second object is moved with respect to the exposure beam having passed through the projection system in synchronization with the movement of the first object with respect to the exposure beam. Thus, in the scanning exposure method for scanning and exposing the second object, a plurality of detection means arranged to detect position information of the second object in the optical axis direction of the projection system during movement of the second object. Among the points, the detection point used for adjusting the positional relationship between the image plane of the projection system and the second object is changed according to the moving direction of the second object.

In a second scanning exposure method according to the present invention, the second object is moved with respect to the exposure beam passing through the projection system in synchronization with the movement of the first object with respect to the exposure beam. In the scanning exposure method for scanning and exposing the second object, a plurality of detection means arranged to detect position information of the second object in the optical axis direction of the projection system while the second object is moving Select and use some of the points.

Next, a first device manufacturing method according to the present invention uses the scanning exposure apparatus of the present invention. Further, a second device manufacturing method according to the present invention uses the scanning exposure method of the present invention.

[0014]

The first scanning type exposure apparatus of the present invention and the first
According to the scanning exposure method, the detection point of the position information of the second object in the optical axis direction of the projection system is changed according to the moving direction (scanning direction) of the second object. Even if the scanning direction is changed, the portion to be exposed on the second object can be aligned with the image plane with high accuracy. Therefore,
The pattern of the mask as the first object is transferred with high precision onto the photosensitive substrate as the second object without lowering the throughput.

According to the second scanning type exposure apparatus and the second scanning exposure method of the present invention, a part of a plurality of detection points of the position information of the second object in the optical axis direction of the projection system is selected. The detection point can be changed according to the scanning direction, for example. Therefore, regardless of the scanning direction of the second object, without lowering the throughput,
The pattern of the mask as the first object is precisely
It is transferred onto a photosensitive substrate as an object.

Next, another operation of the present invention will be described with reference to an embodiment.
The detection of the height of the photosensitive substrate (10) as an object is separated from the exposure area (11) by a distance determined by the phase delay due to the signal processing time of the focus position detection means and the feed speed of the substrate stage (12, 13). Done in a place. Then, the focusing based on the detected height of a certain exposed area (30) is performed when the exposed area (30) moves to the exposed area (11). The phase delay of the position detecting means and the like can be canceled, and the focusing can be performed accurately.

Similarly, the detection of the tilt angle of the photosensitive substrate (10) as the second object by the tilt angle detecting means is based on the phase delay due to the signal processing time of the tilt angle detecting means and the feed speed of the substrate stage (12, 13). This is carried out at a place separated from the exposure area (11) by a distance determined by the above. Then, the leveling based on the detected inclination angle of a certain exposed area (30) is performed by setting the exposed area (30) to the exposed area (1).
Since it is performed when moving to 1), the phase difference and the like of the inclination angle detecting means and the like can be canceled by the time difference between them, and leveling is performed accurately.

[0018]

An embodiment of the present invention will be described below with reference to the drawings. In the present embodiment, the present invention is applied to a slit scan exposure type projection exposure apparatus that uses a pulse oscillation type light source such as an excimer laser light source as a light source for exposure light. FIG. 1 shows a projection exposure apparatus of the present embodiment,
In FIG. 1, pulse light from a pulse laser light source 1 such as an excimer laser light source enters an illumination optical system 2. The pulse emission timing of the pulse laser light source 1 is arbitrarily set by a trigger control unit (not shown). The illumination optical system 2 includes a beam shaping optical system, a dimming optical system, an optical integrator, a field stop, a condenser lens system, and the like. The pulse light is converted by the illumination optical system 2 into pulse exposure light IL having substantially uniform illuminance. The pulse exposure light IL illuminates the reticle 3.

The reticle 3 is held on a reticle stage 4, and the reticle stage 4 is in a direction perpendicular to the optical axis of the projection optical system 9 in an X direction (or -X direction) parallel to the plane of FIG.
In addition to scanning the reticle 3, the reticle 3 is positioned in the Y direction perpendicular to the X direction (the direction perpendicular to the plane of FIG. 1). A reticle blind 5 having a rectangular opening is arranged on the lower surface of reticle stage 4, and a rectangular illumination area is substantially set on reticle 3 by the opening of reticle blind 5. A movable mirror 6 is fixed on the reticle stage 4, and a laser beam from an external reticle-side interferometer 7 is reflected by the movable mirror 6, and the reticle-side interferometer 7 coordinates the reticle stage 4 in the X and Y directions. Is constantly measured, and the coordinate information S1 thus measured is supplied to a main control system 8 that controls the operation of the entire apparatus.

In the pattern drawn on the reticle 6,
An image of a portion limited by the opening of the reticle blind 5 is projected via a projection optical system 9 onto a wafer 10 coated with a photoresist as a photosensitive substrate. A region conjugate with respect to the projection optical system 5 and a region on the reticle 3 which is limited by the opening of the reticle blind 5 is a rectangular exposure region 11. Further, the wafer 10 is held on a Z-leveling stage 12,
Is mounted on the XY stage 13 on the wafer side. A Z leveling stage 12 for positioning the wafer 10 in the Z direction which is the optical axis direction of the projection optical system 9;
It is composed of a leveling stage and the like for tilting the exposure surface of the wafer 10 by a desired tilt angle. On the other hand, the wafer-side XY stage 13 scans the wafer 10 in the X direction.
It comprises a stage and a Y stage for positioning the wafer 10 in the Y direction.

A movable mirror 14 is attached to a side surface of the Z leveling stage 12, and an external wafer-side interferometer 1 is provided.
5 is reflected by the moving mirror 14, and the X-ray of the wafer-side XY stage 13 is
The coordinates and the Y coordinate are constantly measured, and the coordinate information thus measured is supplied to the main control system 8. Further, the height (focus position) and inclination currently set in the Z-leveling stage 12 are detected by the Z-leveling stage position detecting device 17, and information on the detected height and inclination is sent to the arithmetic device 18. Supplied. The position detecting device 17 for the Z leveling stage is composed of, for example, a rotary encoder attached to the shaft of the drive motor or a potentiometer for directly detecting the height.

Then, multi-point focus position detecting devices 19 and 2 are provided on both side portions of the projection optical system 9 in the X direction.
0 is arranged. FIG. 2 shows the relationship between the detection areas of the multi-point focus position detection devices 19 and 20 and the rectangular exposure area 11. In FIG.
1a, centering on a position 21a at an interval D in the -X direction.
A detection area 21 having substantially the same size as the exposure area 11 is set. 5 on the side in the -X direction of this detection area 21
The first multi-point focus position in FIG. 1 is obliquely positioned on the four detection points 22A to 26A and the five detection points 22B to 26B on the side in the X direction, obliquely to the normal to the exposure surface of the wafer 10. A slit pattern image is projected from the detection device 19. As illumination light for projecting the slit pattern image, light in a wavelength region having low photosensitivity to the photoresist is used.

The reflected light from these ten slit pattern images returns to the multipoint focus position detecting device 19, and the multipoint focus position detecting device 19 outputs the re-formed images of the ten slit pattern images. Ten focus signals corresponding to the amount of lateral displacement from the reference position are generated. When the height of the wafer 10 in the Z direction changes,
Since the positions of the re-formed images of the zero slit pattern images are shifted laterally, the detection points 22A to 26A and 22B to 22B of the detection area 21 are respectively obtained from the ten focus signals.
The height (focus position) of the wafer 10 at 26B is detected.

Further, in FIG. 2, from the center 11a of the exposure area 11, a position 27a at a distance D in the X direction is used as a center.
A detection area 27 having a size substantially equal to that of the exposure area 11 is set. On ten detection points on the detection area 27, the detection area 27 is oblique to the normal to the exposure surface of the wafer 10.
Each of the second multi-point focus position detecting devices 20 shown in FIG.
, A slit pattern image is projected. These 10
The reflected light from each of the slit pattern images returns to the multipoint focus position detection device 20, and the multipoint focus position detection device 20
, And generates ten focus signals corresponding to the height.
For example, when the wafer 10 is scanned in the scanning direction RW along the X direction, the height information detected by the first multi-point focus position detection device 19 for the detection area 21 is used, and the wafer 10 is moved to -X Scanning direction RW 'along the direction
In the case where the scanning is performed, the height information detected by the second multipoint focus position detection device 20 for the detection area 27 is used.

Returning to FIG. 1, the information of the first set of ten focus signals and the information of the second set of ten focus signals S2 respectively output from the multipoint focus position detectors 19 and 20 are calculated by the arithmetic unit 18. Is supplied to The arithmetic unit 18 calculates the height and inclination (target height) to be set by the Z-leveling stage 12 with respect to the area to be exposed next in the exposure area 11 based on the information on the focus position read in advance as described later. And the target inclination), and informs the main control system 8 of information on the target height and the target inclination. The main control system 8 controls the operation of the Z leveling stage 12 via the wafer stage control device 16 according to this information. In addition, the main control system 8 scans the reticle stage 4 via a reticle stage control device (not shown) and synchronizes the scanning operation of the reticle side XY stage 13 with the wafer stage control device 16. Control.

In this embodiment, when performing exposure by the slit scan exposure method, for example, the wafer 10 is moved to the XY stage 13 in synchronization with the reticle 3 being scanned by the reticle stage 4 in the scanning direction RR (−X direction). Scanning direction RW
(X direction). In this case, assuming that the projection magnification of the projection optical system 9 is β and the scanning speed of the reticle 3 is VR, the scanning speed of the wafer 10 is β · VR. Thereby, all the patterns on the reticle 3 are sequentially exposed on the wafer 10. However, the scanning direction may be reversed. When the reticle 3 is scanned in the X direction, the wafer 10 is scanned in the −X direction in synchronization with the scanning.

The moving speed of the reticle stage 4 and the XY stage 13 on the wafer side during the slit scan exposure is determined by the amount of the pulse exposure light IL irradiated onto the reticle 3, the width of the opening of the reticle blind 5 and the application speed to the wafer 10. Determined by the sensitivity of the applied photoresist. That is, the speed of the reticle stage 4 is determined such that the photoresist on the reticle 3 is sufficiently exposed within the time required for the pattern on the reticle 3 to cross the opening of the reticle blind 5 by the movement of the reticle stage 4. Further, the center point 11a of the exposure area 11 and the center point 21a of the detection area 21 (or 27) shown in FIG.
(Or 27a) is equal to or longer than the distance that the wafer-side XY stage 13 moves during the delay time due to the signal processing time in the multipoint focus position detector 19 (or 20) and the arithmetic unit 18. Is set to the length.

Next, referring to the flowchart of FIG.
An example of the exposure operation of the present example will be described. In the exposure operation of this example, the following conditions are premised. The reference plane on which the surface of the portion to be exposed on the wafer 10 is aligned is the image plane (best imaging plane) of the projection optical system 9. The height and inclination set by the Z-leveling stage 12 are the same as the surface of a wafer having a good flatness (super flat wafer) held on the Z-leveling stage 12 via a wafer holder (not shown). Height and inclination. Such a surface determined by the height and the inclination set in the Z leveling stage 12 is called a “holder surface”.

The center of rotation during leveling of the Z leveling stage 12 in FIG. 1 is the center 1 of the exposure area 11 in FIG.
1a. That is, the XY stage 13 on the wafer side
When the leveling is performed by the Z leveling stage 12 irrespective of the values of the X coordinate and the Y coordinate, the height (focus position) of the wafer 10 at the center 11 a of the exposure area 11 does not change.

Under such conditions, first, step 1 in FIG.
At 01, calibration of focus signals respectively corresponding to the ten detection points 22A to 26A and 22B to 26B in the detection area 21 and the ten detection points in the detection area 27 in FIG. For example, in order to calibrate focus signals corresponding to the detection points 22A to 26A and 22B to 26B in the detection area 21, a test reticle on which a pattern for focus measurement is formed on the reticle stage 4 in FIG. The wafer is placed and held on a Z leveling stage 12 shown in FIG. Then, with the inclination of the Z leveling stage 12 fixed at zero and the height set to a predetermined value, focus signals corresponding to these ten detection points are obtained via the multipoint focus position detection device 19. Thereafter, the XY stage 13 on the wafer side is driven to move the portion to be exposed in the detection area 21 of FIG.
The exposed portion is exposed to a test reticle pattern.
In addition, using another exposed portion of the wafer for test baking, the height (focus position) at the Z leveling stage 12 is slightly changed, and ten focus signals are obtained. Expose the test reticle pattern.

Thereafter, by developing the wafer, each detection point 22A to 26A,
In 22B to 26B, the focus position when the test reticle pattern is formed most sharply, that is, the image plane position of the projection optical system 9 is obtained. Thus, the reference level corresponding to the image plane position of the projection optical system 9 of each focus signal corresponding to the detection points 22A to 26A and 22B to 26B is obtained. Similarly, the other detection area 27
The reference level corresponding to the image plane position of the projection optical system 9 is also obtained for the focus signals corresponding to the ten detection points in the above.

Next, in step 102, the reticle 3 on which the pattern for transfer has been formed is moved to the reticle stage 4
Then, the wafer 10 to be exposed to which the photoresist is applied is loaded on the Z leveling stage 12. Then, in synchronization with the start of the scanning of the reticle 3 in the scanning direction RR, the scanning of the wafer 10 in the scanning direction RW is started. Next, in step 103, FIG.
As shown in (a), the center of the exposed portion 30 on the wafer 10 is positioned at the detection area 21 of the multi-point focus position detection device 19.
At the center 21a of the detection point 22A shown in FIG.
To 26A (collectively referred to as “detection point XA”) and detection points 22B to 26B (collectively referred to as “detection point XA”).
B ") is obtained by the multi-point focus position detecting device 19, and these focus signals are supplied to the arithmetic device 18. This is equivalent to obtaining the height (focus position) of the exposed portion 30 at the detection points XA and XB. The average of the heights measured at the five detection points XA is Z _1A , and the average of the heights measured at the five detection points XB is Z _1B .

Further, the center of the exposed portion 30 is
At the time when the center 21a is reached, the height and inclination set in parallel with the Z-leveling stage 12 in FIG. 1 via the Z-leveling stage position detecting device 17, ie, the holder shown in FIG. Center 11 of exposure area 11 on surface 29
The height Z _H0 and the inclination at a are detected, and the height Z _H0 and the inclination are supplied to the arithmetic unit 18. Note that the inclination is represented by the tangent of the inclination angle, and the inclination angle of the holder surface 29 in the XZ plane is θ _HX , and the inclination angle in the YZ plane is θ _HY .

Thereafter, in step 104, the arithmetic unit 18 sets the exposed portion 3 based on the holder surface 29 as a reference.
An average height (average height) Z _1C in the 0 detection area 21 is obtained by the following equation. In the following, the distance D between the center 11a of the exposure area and the center 21a of the detection area can be considered as a prefetch distance.

## EQU1 ## Z _1C = (Z _1A + Z _1B ) / 2-D · tan θ _HX

Further, the arithmetic unit 18 calculates an average inclination (average inclination) in the detection area 21 of the exposed portion 30 with reference to the holder surface 29. Since the surface of the wafer 10 has irregularities due to the process, the inclination of the exposed portion 30 on the wafer 10 refers to the average inclination of the surface in the exposed portion 30, that is, the local surface of the wafer 10. It is a slope. First, assuming that the distance in the X direction between the detection points XA and XB in the X direction is E and the inclination angle corresponding to the average inclination in the XZ plane is θ _1X , the inclination tan θ _1X is as follows.

Tan θ _1X = (Z _1A −Z _1B ) / E-tan θ _HX

The inclination (inclination angle θ _1Y ) in the YZ plane in the detection area 21 of the exposed portion 30 with reference to the holder surface 29 is, for example, the average of the detection points 22A and 22B in FIG. Is Z _1D , the average height of the detection points 26A and 26B is Z _1E , and the interval in the Y direction between the detection points 22A and 26A is E, the following equation is obtained.

Tan θ _1Y = (Z _1D -Z _1E ) / E-tan θ _HY

Next, at step 105, the arithmetic unit 1
8 is to move the exposed portion 30 to the exposure area 11 and perform exposure.
Height to set on the Z leveling stage 12
(Target height) Z_H And the slope to be set (target slope)
Confuse. These target heights Z_H And the target slope are
The height Z of the best imaging plane 28 of the projection optical system 9 which is a quasi-plane ₀ 
And the inclination, the average height and the average inclination of the exposed portion 30 are calculated.
It has been deducted. That is, the target height Z_H Is as follows
become.

## EQU4 ## Z _H = Z ₀ −Z _1C

XZ of the inclination angle of the image plane of the projection optical system 9
_Assuming that the inclination angle in the plane is θ _0X and the inclination angle in the YZ plane is θ _0Y , the inclination angle θ _X in the XZ plane and the inclination angle θ in the YZ plane of the inclination angles of the target inclinations _Y is as follows.

Tan θ _X = tan θ _0X -tan θ _1X , tan θ _Y = tan θ _0Y -tan θ _1Y

Thereafter, in step 106, FIG.
(B), when the exposed portion 30 on the wafer 10 has reached the exposure region 11, the main control system 8 sets the height to set the Z-leveling stage 12 to the target height Z _H And X set on the Z leveling stage 12
The inclination in the Z plane and the inclination in the YZ plane are set to target inclinations tan θ _X and tan θ _Y respectively. At the same time, in step 107, the main control system 8 causes the pulse laser light source 1 in FIG. 1 to emit light, and exposes the pattern of the reticle 3 to the exposed portion 30 on the wafer 10. At this time,
The exposed portion 30 substantially matches the best imaging plane 28.

The above description relates to the operation in the case where a certain exposed portion 30 on the wafer 10 is exposed.
Actually, the exposure operation of FIG. 4 is repeated in a time series for a series of exposed portions on the wafer 10 in the X direction. As described above, according to this example, the height and the inclination of each of the exposed portions on the wafer 10 are read in advance, and the height and the inclination of the Z-leveling stage 12 are adjusted based on the result of the pre-read during the exposure. I have. Therefore, wafer 1
Even if there are local irregularities on the exposure surface 0, the wafer 1
The pattern of the reticle 3 can be exposed on the exposure surface of the wafer 1 in a state where the entire exposure surface is aligned with the image surface of the projection optical system 9.

In the above embodiment, since the pulse laser light source 1 is used as the light source of the exposure light, the exposure timing can be accurately adjusted when the exposed portion 30 reaches the exposure area 11. . However, even when continuous light such as a mercury lamp is used as the exposure light, the height of the exposed portion 30 is read in advance so that the exposed portion 30 can be almost accurately positioned on the image plane of the projection optical system 9 during exposure. Can be adjusted.

As described above, the present invention is not limited to the above-described embodiment, and can take various configurations without departing from the gist of the present invention.

[0043]

According to the present invention, since the detection point of the position information can be changed in accordance with the moving direction of the second object, the pattern of the first object (mask) can be accurately extracted without lowering the throughput. It can be transferred onto two objects (photosensitive substrate). Further, prior to exposure, the height of a region to be exposed on a photosensitive substrate as a second object is detected at a position separated from the reference point of the exposure region of the projection system (projection optical system) by a predetermined distance. In the case where focusing is performed at the exposure position of the exposed area based on the above, there is an advantage that accurate focusing can be performed without being affected by the phase delay due to the signal processing time of the focus position detecting means. is there. Further, since the feed speed of the substrate stage on which the photosensitive substrate is mounted does not need to be reduced more than necessary, the throughput does not decrease.

In the substrate stage, when the exposed portion is exposed, the height is set to a height obtained by adding a difference between the height of the exposed portion obtained by the prefetching and the height of the image plane to the height set at the time of the prefetching. In this case, the calculation can be performed at a high speed and the control is easy. Similarly, the adjustment of the positional relationship is based on the direction intersecting the moving direction of the second object and the relationship between the image plane of the projection system and the inclination of the second object with respect to at least one of the moving directions of the second object. In the case where the adjustment is included, the inclination amount of the exposed area on the photosensitive substrate as the second object is detected prior to the exposure, so that the influence of the phase delay due to the signal processing time of the inclination angle detecting means is reduced. There is an advantage that accurate leveling can be performed without receiving. Further, the control is easy without a decrease in throughput.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a projection exposure apparatus to which an exposure method according to an embodiment of the present invention is applied.

FIG. 2 is a plan view showing a relationship between an exposure area and a detection area in FIG.

FIG. 3A is a diagram showing a state of a portion to be exposed during pre-reading,
(B) is a diagram showing a state of a portion to be exposed at the time of exposure.

FIG. 4 is a flowchart illustrating an example of an exposure operation according to the embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 pulse laser light source 2 illumination optical system 3 reticle 4 reticle stage 5 reticle blind 8 main control system 9 projection optical system 10 wafer 11 exposure area 12 Z leveling stage 13 wafer-side XY stage 16 wafer stage control device 17 position detection for Z leveling stage Device 18 Arithmetic unit 19, 20 Multi-point focus position detection device

Claims (15)

[Claims] 1. A scan for scanning and exposing a second object by moving a second object with respect to an exposure beam passing through a projection system in synchronization with moving a first object with respect to the exposure beam. A type exposure apparatus, comprising: a detection unit having a plurality of detection points capable of detecting position information of the second object in an optical axis direction of the projection system while the second object is moving; Adjusting means for adjusting the positional relationship between the image plane of the projection system and the second object, and adjusting the positional relationship between the image plane of the projection system and the second object among the plurality of detection points. A scanning exposure apparatus, wherein a detection point used for performing the scanning is changed according to a moving direction of the second object. 2. A scan for scanning and exposing the second object by moving the second object with respect to the exposure beam passing through the projection system in synchronization with moving the first object with respect to the exposure beam. A pattern exposure apparatus, comprising: a detection unit having a plurality of detection points capable of detecting position information of the second object with respect to an optical axis direction of the projection system while the second object is moving, based on a detection result of the detection unit Adjusting means for adjusting the positional relationship between the image plane of the projection system and the second object, and selectively using a part of the plurality of detection points to form the image plane of the projection system and the second object. A scanning exposure apparatus for adjusting a positional relationship between two objects. 3. The scanning exposure apparatus according to claim 1, wherein the plurality of detection points include a plurality of detection points separated in a direction intersecting a moving direction of the second object. 4. A plurality of detection points in a direction intersecting the moving direction of the second object have a width substantially equal to an irradiation area of the exposure beam passing through the projection system in a direction intersecting the moving direction of the second object. The scanning type exposure apparatus according to claim 3, wherein the scanning type exposure apparatus is disposed inside the apparatus. 5. The scanning exposure apparatus according to claim 1, wherein the plurality of detection points include a plurality of detection points separated in a moving direction of the second object. . 6. The image processing apparatus according to claim 1, wherein the adjusting unit is configured to control an image plane of the projection system with respect to a direction intersecting a moving direction of the second object.
The scanning exposure apparatus according to any one of claims 1 to 6, wherein the relationship between the inclination and the object is adjusted. 7. The scanning exposure apparatus according to claim 6, wherein the adjustment unit tilts the second object about a predetermined point in the irradiation area as a center of rotation. 8. A device manufacturing method using the scanning exposure apparatus according to claim 1. 9. A scan for scanning and exposing the second object by moving the second object with respect to the exposure beam having passed through the projection system in synchronization with the movement of the first object with respect to the exposure beam. In the exposure method, among a plurality of detection points arranged to detect position information of the second object with respect to an optical axis direction of the projection system during movement of the second object, an image plane of the projection system and A scanning exposure method, wherein a detection point used for adjusting a positional relationship with the second object is changed according to a moving direction of the second object. 10. A scan for scanning and exposing the second object by moving the second object with respect to the exposure beam passing through the projection system in synchronization with moving the first object with respect to the exposure beam. In the exposure method, during the movement of the second object, a part of a plurality of detection points arranged for detecting position information of the second object in the optical axis direction of the projection system is selected and used. A scanning exposure method. 11. The scanning exposure method according to claim 9, wherein the plurality of detection points include a plurality of detection points separated in a direction intersecting a moving direction of the second object. 12. The scanning exposure method according to claim 9, wherein the plurality of detection points include a plurality of detection points separated in a moving direction of the second object. 13. A movement of the image plane of the projection system in a direction intersecting with a movement direction of the second object and the second object based on a detection result at the detection point during the movement of the second object. The scanning exposure method according to claim 9, further comprising adjusting a relationship between inclinations. 14. The relationship between the image plane of the projection system and the inclination of the second object is adjusted by adjusting the inclination of the second object around a predetermined point in the irradiation area as a center of rotation. The scanning exposure method according to claim 13, wherein: 15. A device manufacturing method using the scanning exposure method according to claim 9.