JP2000106340A - Aligner, scanning exposure method, and stage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the throughput of a scanning type exposure device. SOLUTION: When a mask pattern is transferred sequentially on a plurality of shot regions (S1 and S2, etc.), on a sensitized substrate, the substrate is controlled for moving so that a preliminary operation (pre-scan and over scan before/after a shot exposure time (t3)) for a next shot S2 exposure after the completion of a substrate exposure in the figure (B) and a stepping operation in non-scan direction for the next shot exposure in the figure (C) are performed at the same time in parallel after the scan exposure completion of a shot S1, while the stepping operation is completed before a synchronization settling time (t2) between a mask and a substrate before next shot exposure. As a result, the substrate is scanned relative to the center of a lighting slit ST along a path such as a curved line as in a solid line in the figure (A), resulting in shortened movement time between the exposures of the shot S1 and the shot S2 as compared to conventional examples with movement along the solid line curve path.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an exposure apparatus, a scanning exposure method, and a stage apparatus.
For example, the present invention relates to an exposure apparatus and a scanning exposure method used when a circuit device such as a semiconductor circuit element or a liquid crystal display element is manufactured by a lithography process, and a stage apparatus suitable for the exposure apparatus.

[0002]

2. Description of the Related Art At present, at a semiconductor device manufacturing site,
The minimum line width is 0.3 using a reduction projection exposure apparatus, a so-called stepper, using i-line of a mercury lamp having a wavelength of 365 nm as illumination light.
Circuit devices of about 0.35 μm (64 M (mega) bit D-RAM and the like) are mass-produced. At the same time, 2
An exposure apparatus for mass-producing a next-generation circuit device having a 56 Mbit, 1G (giga) bit D-RAM class integration density and a minimum line width of 0.25 μm or less has begun to be introduced.

As an exposure apparatus for manufacturing the next generation of circuit devices, a wavelength 248 from a KrF excimer laser light source is used.
An ultraviolet pulse laser beam having a wavelength of 193 nm or an ultraviolet pulse laser beam having a wavelength of 193 nm from an ArF excimer laser light source is used as illumination light. By scanning the wafer one-dimensionally relative to the projection field of view of the reduction projection optical system, a scanning exposure operation for transferring the entire reticle circuit pattern into one shot area on the wafer and an inter-shot stepping operation are repeated. The scanning exposure apparatus of the step-and-scan method is considered to be promising.

[0004] Such a step-and-scan type scanning exposure apparatus includes a refractive optical element (lens element).
First, a PerkinElmer Micra Scan exposure apparatus equipped with a reduction projection optical system composed of a reflection optical element (such as a concave mirror) is commercialized and commercially available. The Micra scan exposure apparatus is described in, for example, SPIE, Vol. As described in detail in p. 424 to 433 of 1088, while projecting a part of the reticle pattern onto the wafer through the effective projection area limited in the shape of an arc slit, the projection magnification ( 1
By performing relative movement at a speed ratio corresponding to (/ 4 reduction), a shot area on a wafer is exposed.

In a step-and-scan projection exposure method, an excimer laser beam is used as illumination light,
A method of limiting the effective projection area of a reduction projection optical system having a circular projection field of view to a polygon (hexagon) and partially overlapping both ends of the effective projection area in the non-scanning direction, a so-called scan & stitch method. Are disclosed in, for example, JP-A-2-229423.
A projection exposure apparatus employing such a scanning exposure method is disclosed in, for example, JP-A-4-196513 and JP-A-4-196513.
No. 277612, JP-A-4-307720 and the like.

In the step-and-scan type scanning exposure apparatus, when sequentially transferring a reticle pattern to a plurality of shot areas (hereinafter, appropriately referred to as "shots") on a wafer, the throughput is improved in order to improve the throughput.
Normally, the reticle is alternately scanned (reciprocally scanned) to sequentially expose the next shot. For this reason, after the transfer of the reticle pattern to one shot is completed, at the time of prescanning before the start of exposure (acceleration time up to the target speed (scanning speed at the time of exposure) + the speed after the end of acceleration, the target speed is within a predetermined error range). An operation (overscan) is required in which the reticle is further moved from the end of the exposure by the same distance as the settling time until the reticle converges, and the reticle is returned to the scanning start position for the next shot exposure. Correspondingly, the wafer is shot next (another shot adjacent to the one shot in the non-scanning direction).
In addition to the stepping operation, a movement in the scanning direction is also required.

The movement operation between shots of the wafer is as follows.
Conventionally, the following procedure has been performed. After the exposure is completed, the wafer stage (substrate stage) is once moved to the same coordinate position in the scanning direction as the scanning start position of the next shot,
Stepping is performed in the non-scanning direction up to the scanning start position of the next shot, and scanning for exposure of the next shot is started.
Therefore, the wafer was moved along the U-shaped path.

[0008]

By the way, improving the throughput (processing capability) is one of the most important issues for an exposure apparatus, and since it is necessary to achieve this, the acceleration / deceleration of a reticle during scanning exposure is, for example, 0.1 mm. 5G → 4G, the maximum speed is also increased from 350 mm / s → 1500 mm / s, and accordingly, the acceleration / deceleration and the maximum speed at the time of scanning exposure of the wafer stage are also proportional to the projection magnification 1 / n. . For this reason, it is necessary to extend the movement distances required before and after exposure during prescanning and overscanning accordingly.

For this reason, although the acceleration / deceleration and the maximum speed are increased from the viewpoint of originally improving the throughput, there is a disadvantage that the throughput may be rather deteriorated as a result.

[0010] Further, the improvement of the throughput by shortening the stepping time between shots (including the positioning settling time at the time of movement) is also required for a static exposure type exposure apparatus such as a stepper.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an exposure apparatus capable of improving throughput.

It is still another object of the present invention to provide a scanning exposure method capable of improving the throughput.

[0013]

According to the first aspect of the present invention, a plurality of shot areas (S1) on the sensitive substrate (W) are moved by synchronously moving the mask (R) and the sensitive substrate (W). , S2, etc.), an exposure apparatus for sequentially transferring the pattern of the mask, the substrate stage (WST) holding the sensitive substrate (W) and moving in a two-dimensional plane; and holding and moving the mask Possible mask stage (RS
T), a running operation for the next shot exposure after the exposure of the substrate stage and a stepping operation in the non-scanning direction for the next shot exposure are performed simultaneously in parallel, and A stage control system (33,
78, 80).

According to this, when the mask pattern is sequentially transferred to a plurality of shot areas on the sensitive substrate, the stage control system performs the next shot exposure after the end of the exposure of the substrate stage after the end of the scanning exposure of a certain shot. (The prescan and overscan before and after the exposure time for scanning and exposing the shot) and the stepping operation in the non-scanning direction for the next shot exposure are performed simultaneously in parallel, and the stepping in the non-scanning direction is performed. Both stages are controlled so that the operation is completed before the synchronization period of both stages before the next shot exposure. For this reason, the approach operation of the substrate stage in the scanning direction and the stepping operation of the next shot in the non-scanning direction (adjacent shot in the non-scanning direction) are performed simultaneously and in parallel, and the conventional substrate stage comprising The movement time is shorter than the movement control between shots. Of course, in the related art, if the substrate stage has a two-stage structure including the scanning direction moving stage and the non-scanning direction moving stage, the above operations can be performed simultaneously and in parallel. Since the scanning of the next shot has not yet begun at the time when is completed, the stepping operation is completed before the synchronization period of both stages before the next shot exposure.
In other words, at the time when the stepping is completed, it is clear that the present invention improves the throughput because the operation has already been started and the acceleration period has been completed. Further, according to the present invention, since the stepping is completed before the synchronization stabilization period between the mask stage and the substrate stage before the next shot exposure, during the synchronization stabilization period, it is possible to concentrate on only constant-speed synchronization control of both stages. Does not become long.

According to the first aspect of the present invention, as in the second aspect, the stage control system (33,
78, 80) are the substrate stage (WST) corresponding to the overscan consisting of the constant speed movement time and the deceleration time of the mask stage (RST) after the previous shot exposure.
Are controlled such that the absolute value of the acceleration in the non-scanning direction becomes larger than the deceleration in the non-scanning direction of the portion corresponding to the pre-scanning of the mask stage (mask stage) before the start of the exposure of the next shot. It is more desirable. In such a case, the shaking (vibration) of the exposure apparatus main body that occurs at the time of high acceleration during stepping is attenuated during deceleration. Can completely attenuate the vibration, thereby improving the controllability, shortening the settling time and improving the throughput.

According to a third aspect of the present invention, there is provided a scanning exposure method for sequentially transferring a pattern of a mask (R) to a plurality of divided areas (S1, S2) on a substrate (W). A first synchronous movement is performed to scan and expose one (S1) of the plurality of divided areas, and the first substrate is synchronously moved.
In order to scan and expose another partitioned area (S2) adjacent to the one partitioned area in a second direction orthogonal to the direction,
The acceleration of the substrate in the first direction is started before the stepping operation of the substrate in the second direction after the scanning exposure of the one divided area (S1) is completed.

According to this, the mask and the substrate are moved synchronously, and after one of the plurality of divided areas is scanned and exposed, the first
The second direction of the substrate after the scanning exposure of one partitioned area is performed in order to scan and expose another partitioned area adjacent to one partitioned area in a second direction (non-scanning direction) orthogonal to the direction (scanning direction). Is performed, but before the stepping operation is completed, the acceleration of the substrate in the first direction is started. That is, a non-scanning direction moving (stepping) operation for exposing another partitioned area adjacent to the one partitioned area in the non-scanning direction is started after the end of the exposure of one partitioned area. Since the acceleration of the substrate in the scanning direction is started in the step (b), the stepping time in the non-scanning direction can at least partially overlap the acceleration time in the scanning direction for exposure of the adjacent area (another divided area). It is possible to improve the throughput as compared with the conventional example in which the stepping operation in the non-scanning direction for exposing another partitioned area is completed and then the acceleration in the scanning direction for exposing the adjacent area is started. is there.

[0018] In this case, as in the fourth aspect of the present invention, the substrate (W) is provided in the separate partition area (S2).
Prior to the scanning exposure, it is preferable that the substrate is moved obliquely with respect to the first and second directions by the acceleration, and the moving speed in the first direction is set to a speed according to the sensitivity characteristic of the substrate. In such a case, the moving speed in the first direction is set to a speed corresponding to the sensitivity characteristic of the substrate before the scanning exposure of another divided area (S2), so that the speed is maintained during the exposure and the mask is synchronously controlled. Control is easy.

In the scanning exposure method according to the third or fourth aspect, as in the invention according to the fifth aspect, after the scanning exposure of the one partitioned area (S1) is completed, the other partitioned area is scanned and exposed. The substrate may be moved in the second direction while decelerating in the first direction until the substrate separates in the first direction by a necessary approach distance.

In each of the third to fifth aspects of the present invention, as in the sixth aspect of the present invention, the substrate (W)
Is that at least one of the speed component in the first direction and the speed component in the second direction is between the scanning exposure of the one section area (S1) and the scanning exposure of the another section area (S2). It is desirable that the movement is performed so as not to be zero. In such a case, since the substrate is moved without stopping between the scanning exposure of one partitioned area (S1) and the scanning exposure of the other partitioned area (S2), the throughput is improved accordingly. Because.

In each of the third to sixth aspects of the present invention, as in the seventh aspect of the present invention, the substrate (W) is
Between the scanning exposure of the one partitioned area (S1) and the scanning exposure of the another partitioned area (S2), the position in the second direction at which the moving speed in the first direction becomes zero is the one partitioned area. The movement may be performed so as to be closer to the another divided area than the area. In such a case, even if the acceleration and deceleration of the substrate in the non-scanning direction between the scanning exposure of one partitioned area and the scanning exposure of another partitioned area are equal, the scanning of another partitioned area must be performed. Since the speed in the non-scanning direction has become zero a predetermined time before the start of the exposure, the movement in the non-scanning direction ends at a certain time before the start of the scanning exposure of another partitioned area. Therefore, it is not necessary to increase the deceleration of the substrate after the acceleration in the non-scanning direction between the scanning exposure of one partitioned area and the scanning exposure of another partitioned area. The effect does not remain, and the synchronization settling time does not become unnecessarily long.

According to an eighth aspect of the present invention, the mask (R) and the substrate (W) are synchronously moved, and the substrates are arranged in a second direction substantially orthogonal to the first direction in which the substrate is synchronously moved. A first partitioned area (S1) and a second partitioned area (S1) on the substrate
2) wherein each of the first and second sections is scanned and exposed by the pattern of the mask.
Moving the substrate in the second direction while decelerating the substrate until the moving speed of the substrate in the first direction becomes zero;
The substrate is moved in the second direction while being accelerated in the first direction before scanning exposure of the partitioned area.
According to this, after the scanning exposure of the first sectioned area is completed,
Since the substrate is moved along a parabolic path, the substrate is moved along a path that is close to the shortest distance, and the throughput can be improved accordingly.

In this case, as in the ninth aspect of the present invention, the position of the substrate (W) in the second direction at which the moving speed in the first direction becomes zero is determined by the second direction in the second direction. It may be set between both ends of the divided area (S2). In such a case, even if the acceleration and the deceleration of the substrate in the non-scanning direction between the scanning exposure of the first partitioned area and the scanning exposure of the second partitioned area are equal, the scanning of the second partitioned area must be performed. Since the speed in the non-scanning direction has become zero a predetermined time before the start of the exposure, the movement in the non-scanning direction ends at a certain time before the start of the scanning exposure of the second partitioned area.
Therefore, it is not necessary to increase the deceleration after the acceleration of the substrate in the non-scanning direction between the scanning exposure of the first partitioned area and the scanning exposure of the second partitioned area. The effect does not remain, and the synchronization settling time does not become unnecessarily long.

According to a tenth aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved, and the first partitioned area (S1) on the substrate is arranged in a second direction substantially orthogonal to the first direction in which the substrate (W) is synchronously moved. In the scanning exposure method for transferring the pattern of the mask to each of the divided areas (S2), after the scanning exposure of the first divided area (S1), the substrate is moved so that its movement locus becomes substantially parabolic. And scanning and exposing the second divided area (S2) with the pattern of the mask.
According to this, after the scanning exposure of the first sectioned area and before the start of the scanning exposure of the second sectioned area, the substrate is moved so that its movement trajectory is substantially parabolic. Is moved substantially in the first direction, and the speed component of the substrate in the non-scanning direction does not affect the scanning exposure after the start of the scanning exposure.

In this case, the position of the substrate in the second direction at the vertex of the parabola may be set closer to the second section area than the first section area. desirable.

According to a twelfth aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area (S1) on the substrate are arranged in a second direction substantially orthogonal to a first direction in which the substrate is synchronously moved. S2)
In the scanning exposure method of transferring the pattern of the mask, the deceleration of the substrate after the scanning exposure of the first partitioned area (S1) and the acceleration of the substrate before the scanning exposure of the second partitioned area are performed. In the method, the substrate may be moved in a direction intersecting the first and second directions.
According to this, the substrate is moved in a direction intersecting the first and second directions during the deceleration of the substrate after the scanning exposure in the first partitioned area and during the acceleration of the substrate before the scanning exposure in the second partitioned area. As a result, the movement trajectory of the substrate is shorter than that of the conventional U-shaped path, and the substrate is moved along a path close to the shortest distance, so that the throughput can be improved accordingly.

In this case, the moving locus of the substrate may be V-shaped, but the substrate moves without stopping between the scanning exposure of the first partitioned area and the scanning exposure of the second partitioned area. It is desirable that the locus be parabolic (or U-shaped). In this case, the movement locus of the substrate is not the shortest, but since the substrate does not stop, the total time required for overscan, stepping, and prescan (the time required for the substrate to move between shots) is the shortest.

According to a thirteenth aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved, and the first partitioned area (S1) on the substrate is arranged along a second direction orthogonal to the first direction in which the substrate (W) is synchronously moved. In the scanning exposure method for sequentially transferring the pattern of the mask to two divided areas (S2), after the scanning exposure of the first divided area (S1) is completed, the position of the substrate in the second direction is changed to the second divided area. Before matching the position in the second direction of (S2),
The acceleration of the substrate for scanning exposure of the second partitioned area is started. According to this, after the scanning exposure of the first partitioned area is completed, the movement of the substrate in the second direction is started for the scanning exposure of the second partitioned area. Acceleration of the substrate in the first direction of the substrate is started, and after the movement of the substrate in the second direction for the scanning exposure of the second divided area is completed, the acceleration for the scanning exposure of the second divided area is completed. Throughput can be improved as compared with the case where acceleration is started.

In this case, after the scanning exposure of the first partitioned area (S1) is completed and before the velocity component of the substrate (W) in the first direction becomes zero, as in the fourteenth aspect of the present invention. Moving the substrate obliquely with respect to the first direction,
It is desirable that the substrate is moved immediately after the start of acceleration of the substrate so that the velocity components in the first and second directions do not become zero.

According to a fifteenth aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. (S
2) in which the pattern of the mask is sequentially transferred, before the speed component of the substrate (W) in the second direction after the scanning exposure of the first partitioned area (S1) becomes zero becomes zero. And starting acceleration of the substrate for scanning exposure of the second partitioned area. According to this,
After the scanning exposure of the first sectioned area is completed, the substrate is moved in the second direction toward the second sectioned area. Before the movement is completed and the velocity component of the substrate in the second direction becomes zero. Then, since the acceleration of the substrate for the scanning exposure of the second partitioned area is started, the scanning exposure of the second partitioned area is completed after the movement of the substrate in the second direction for the scanning exposure of the second partitioned area is completed. It is possible to improve the throughput as compared with the case where the acceleration for the start is started.

In this case, the substrate (W) is accelerated in the first direction and decelerated in the second direction, that is, in the second direction of the substrate. It is desirable that the acceleration in the first direction be performed before the scanning exposure of the second partitioned area during the deceleration to the second direction.

In each of the inventions described in claims 15 and 16, as in the invention described in claim 17, the velocity component of the substrate in the first direction after the completion of the scanning exposure of the first partitioned area is zero. It is preferable that the acceleration of the substrate in the second direction is started before the acceleration.

The invention according to claim 18 is a mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. (S
2) in the scanning exposure method of sequentially transferring the pattern of the mask, wherein after the scanning exposure of the first partitioned area (S1) is completed, the second component of the substrate, in which the velocity component of the substrate in the first direction becomes zero. The position in the direction is set to be closer to the first section area than the position of the second section area in the second direction, and in order to scan and expose the second section area with respect to the first and second directions. The method is characterized in that the substrate is moved obliquely. According to this, the moving trajectory of the substrate after the scanning exposure of the first partitioned area is shorter than that of the conventional U-shaped path, and the substrate is moved along the path closest to the shortest distance, thereby improving the throughput. Becomes In this case, the moving locus of the substrate may be V-shaped, but the substrate moves without stopping between the scanning exposure of the first partitioned area and the scanning exposure of the second partitioned area. It is desirable that the locus be parabolic (or U-shaped).

The invention according to claim 19 is a mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. (S
2) In the scanning exposure method of sequentially transferring the pattern of the mask, the substrate is reversed by the first scanning exposure of the first partitioned area (S1) and the second scanning exposure of the second partitioned area (S2). In order to move in the direction, the speed component of the substrate in the first direction is set to zero after the end of the first scanning exposure, and the speed components of the first and second directions are set to zero before the second scanning exposure. The substrate is accelerated so as not to be caused. According to this, the substrate is moved obliquely to the first and second directions along a curved (or straight) path prior to the second scanning exposure.

According to a twentieth aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. (S
2) and a scanning exposure method for sequentially transferring the pattern of the mask between the first scanning exposure of the first partitioned area (S1) and the second scanning exposure of the second partitioned area (S2).
The position in the second direction of the substrate at which the velocity component in the first direction after the first scanning exposure is zero is the position of the first divided region in the second direction and the position of the second divided region in the second direction. The method is characterized in that the substrate is moved so as to be between the position in the second direction. According to this, when the first scanning exposure is completed, the substrate is moved in the second direction while reducing the speed of the substrate in the first direction, and at this time, the speed component of the substrate in the first direction becomes zero. The substrate is moved such that the position in the second direction is between the position in the second direction of the first partitioned area and the position in the second direction of the second partitioned area. Therefore, when the first scanning exposure is completed, the substrate is moved obliquely with respect to the first and second directions along a curved (or straight) path.

According to a twenty-first aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. (S
2) in the scanning exposure method of sequentially transferring the pattern of the mask to the substrate between the first scanning exposure of the first partitioned area (S1) and the second scanning exposure of the second partitioned area (S2). During the deceleration of the substrate after the first scanning exposure and during the acceleration of the substrate before the second scanning exposure, the velocity component in the second direction is set to zero so that the movement trajectory becomes substantially parabolic. The method is characterized in that the substrate is moved without the need. According to this, the movement trajectory of the substrate between the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area becomes substantially parabolic, and the velocity component in the second direction is set to zero. Since the substrate is moved without any trouble, the substrate does not stop, and the total time required for overscan, stepping, and prescan (the time required to move the substrate between shots) is almost the shortest.

In this case, as in the invention according to claim 22, immediately after the completion of the first scanning exposure, and
Immediately before the start of the scanning exposure, the velocity component of the substrate (W) in the second direction may be substantially zero.

According to a twenty-third aspect of the present invention, the mask (R)
And the substrate (W) are synchronously moved, and a first partitioned area (S1) and a second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. (S
2) and a scanning exposure method for sequentially transferring the pattern of the mask between the first scanning exposure of the first partitioned area (S1) and the second scanning exposure of the second partitioned area (S2).
Before the speed component in the first direction of the substrate after the first scanning exposure is completed becomes zero, acceleration of the substrate in the second direction is started, and the speed component of the substrate in the second direction is started. Before the value becomes zero, acceleration of the substrate in the first direction is started. According to this, the movement trajectory of the substrate between the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area is a U-shaped path or a path similar thereto.

In this case, it is preferable that the acceleration of the substrate in the first direction is started during the deceleration of the substrate in the second direction.

In each of the above-mentioned inventions, the acceleration of the substrate (W) in the second direction is performed after the completion of the first scanning exposure. It is desirable to start during the deceleration of the substrate.

In the scanning exposure method according to any one of claims 8 to 25, when the substrate is moved between the divided areas in the second direction, the magnitude of the acceleration is made the same during acceleration and during deceleration. 27. The method according to claim 26, wherein the substrate (W) is moved between the scanning exposure of the first partitioned area (S1) and the scanning exposure of the second partitioned area (S2). When moving in the direction, the absolute value of the acceleration may be different between the time of acceleration and the time of deceleration of the substrate.

According to a twenty-seventh aspect of the present invention, a mask (R)
And the substrate (W) are synchronously moved to the first and second partitioned areas (S1 and S2) on the substrate arranged in a second direction substantially orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method of transferring the pattern of the mask, when the substrate is moved in the second direction between a first scanning exposure of the first partitioned area and a second scanning exposure of the second partitioned area. The absolute value of the acceleration differs between the time of acceleration and the time of deceleration of the substrate.

In such a case, the absolute value and the deceleration of the acceleration during the movement of the substrate in the second direction between the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area are reduced. By appropriately setting the absolute value of the acceleration at the time, the time required for the substrate to move in the second direction may be longer than when the absolute value of the acceleration at the time of acceleration and the absolute value of the acceleration at the time of deceleration are the same. In addition, it is possible to control the movement of the substrate such as shortening the positioning settling time of the substrate after the completion of the movement to shorten the total time required for the movement of the substrate in the second direction including the positioning settling time.

In this case, as in the invention according to claim 28, after the first scanning exposure, the first of the substrate (W) is exposed.
The acceleration of the substrate in the second direction may be started during the deceleration in the direction, and the deceleration of the substrate in the second direction may be started during the acceleration of the substrate in the first direction before the second scanning exposure. . In such a case, the so-called overscan time after the end of the first scanning exposure and the movement time of the substrate between the divided areas, and the so-called prescan time before the second scanning exposure and the movement time of the substrate between the divided areas are each at least one. Since the portions can be overlapped, the throughput can be improved accordingly.

In each of the inventions described in claims 27 and 28, as in the invention described in claim 29, the substrate is
It is desirable to move without stopping between the first scanning exposure and the second scanning exposure.

In this case, as in the invention according to claim 30, the acceleration of the substrate (W) in the second direction is started before and after the speed component in the first direction becomes zero. good.

In each of the twenty-sixth to thirty-sixth aspects of the present invention, as in the thirty-first aspect, the substrate (W)
It is desirable to make the absolute value of the acceleration in the second direction larger during acceleration than during deceleration. In such a case, the acceleration in the second direction of the substrate corresponding to the so-called overscan after the end of the first scanning exposure is smaller than the negative acceleration in the non-scanning direction of the substrate corresponding to the so-called prescan before the start of the second scanning exposure. Since the absolute value can be increased, the vibration of the substrate due to the high acceleration of the substrate in the movement in the second direction can be completely attenuated before the start of the second scanning exposure.

[0048] In the scanning exposure method according to each of the inventions described in claims 8 to 26, as in the invention described in claim 32, the substrate (W) is provided with a scanning exposure of the first partitioned area (S1). It is desirable to move without stopping between the scanning exposure of the second partitioned area (S2).

Further, in the scanning exposure method according to each of the inventions according to claims 8 to 32, as in the invention according to claim 33, the mask (R) prior to the scanning exposure of the second partitioned area (S2). Before the synchronous settling of the substrate and the substrate (W), it is preferable that the velocity component of the substrate in the second direction is made substantially zero. In such a case, before the mask and the substrate are settled synchronously prior to the scanning exposure of the second partitioned area, the second position of the substrate is set.
Since the velocity component in the direction is almost zero, when the scanning exposure is started after the synchronous settling, the movement in the second direction of the substrate between the divided areas does not affect the scanning exposure, and the exposure is performed with high precision. Is possible.

[0050] In the scanning exposure method according to each of the inventions as set forth in claims 10 to 33, as in the invention as set forth in claim 34, the mask (R) may be arranged so that the substrate (W) extends along the first direction. The first partition area (S
It is desirable to reciprocate between the scanning exposure of 1) and the scanning exposure of the second section area (S2). In such a case, no time is required for rewinding the mask between the scanning exposure of the first partitioned area and the scanning exposure of the second partitioned area, and the throughput can be improved accordingly.

[0051] In the scanning exposure method according to each of the inventions as set forth in claims 10 to 34, as in the invention as set forth in claim 35, the substrate (W) may transfer the pattern of the mask (R). All defined areas (S1, S2,
Until the scanning exposure in S3,...) Is finished, it is desirable to move the velocity components in both the first and second directions so that the velocity components do not become zero at the same time. In such a case, since the substrate is moved without stopping from the start of the scanning exposure of the first partitioned area to the end of the scanning exposure of all the partitioned areas on the substrate, the throughput is maximized. Can be done.

According to a thirty-sixth aspect of the present invention, the mask (R) and the substrate are synchronously moved for each of the divided areas on the substrate (W), and the plurality of divided areas (S1, S2, S3) on the substrate are moved. ,
..)), The step-and-scan type scanning exposure method of sequentially transferring the mask pattern is performed between two sections of the substrate on which the mask pattern is transferred by the reciprocating movement of the mask. And moving the substrate without stopping. According to this, since the substrate does not stop between the scanning exposures of the two partitioned areas (usually adjacent areas) to which the pattern of the mask on the substrate is sequentially transferred, the throughput is further improved for that part.

In this case, as in the invention according to claim 37, the substrate (W) remains on the substrate until the scanning exposure of the last partitioned area on the substrate to which the pattern of the mask (R) is to be transferred is completed. Preferably, the substrate is moved such that at least one of the velocity components in the first direction in which the substrate is synchronously moved and the second direction orthogonal thereto is not zero. In such a case, as a result, the substrate does not stop while scanning exposure of the step-and-scan method is performed on all of the plurality of divided areas, so that the throughput is improved most.

In the scanning exposure method according to any one of the third to third aspects of the present invention, as in the thirty-eighth aspect of the present invention, the mask (R) is provided on the substrate (W) during the scanning exposure. It is desirable that the acceleration be started before the velocity components in the two directions become zero. In such a case, since the acceleration of the mask is started before the velocity component of the substrate in the second direction becomes zero, the acceleration of the mask is started after the velocity component of the substrate in the second direction becomes zero. This is because, compared to the case, the time required for the mask and the substrate to be in a synchronized state at a constant speed is shortened, and the throughput can be improved accordingly.

Further, in the scanning exposure method according to each of the inventions described in claims 3 to 38, as in the invention described in claim 39, when the substrate (W) is accelerated before the scanning exposure,
At least one of when the substrate is decelerated after the scanning exposure, the substrate may be moved in the first direction according to an acceleration change curve whose acceleration gradually converges to zero. In such a case, at least one of the time of acceleration of the substrate before scanning exposure and the time of deceleration of the substrate after scanning exposure, the substrate is moved in the first direction according to an acceleration change curve such that the acceleration gradually converges to zero. Because of the movement, the acceleration does not discontinuously, that is, does not suddenly change at the end of acceleration or at the end of deceleration, such as when accelerating to the target scanning speed at a constant acceleration and decelerating to zero at a constant deceleration. Therefore, the high frequency vibration of the substrate caused by the rapid change of the acceleration can be suppressed, and the position error with respect to the target position (which naturally changes with time) can be quickly converged within the allowable range. As a result, the position controllability of the substrate can be improved.

According to a third aspect of the present invention, there is provided a scanning exposure method according to the third aspect, wherein the mask (R) is accelerated before the scanning exposure and after the scanning exposure. The mask may be moved in accordance with an acceleration change curve such that the acceleration gradually converges to zero at least during the deceleration of the mask. In such a case, at least one of the time of acceleration of the mask before scanning exposure and the time of deceleration of the mask after scanning exposure, the mask is moved according to an acceleration change curve such that the acceleration gradually converges to zero. , Accelerate to the target scanning speed at a constant acceleration,
At the end of acceleration, such as when decelerating to zero with a constant deceleration,
Alternatively, the acceleration is not discontinuous at the end of the deceleration, that is, does not suddenly change. Therefore, it is possible to suppress the high-frequency vibration of the mask caused by the rapid change of the acceleration,
A position error with respect to a target position (which naturally changes with time) can be quickly converged within an allowable range, and as a result, the position controllability of the mask can be improved.

In each of the above-described inventions, the substrate (W) or the mask (R) is moved according to the acceleration change curve at the time of acceleration. Is also good. According to this,
When the mask or the substrate is accelerated in the synchronous movement direction based on an acceleration change curve whose acceleration gradually converges to zero prior to the synchronous movement, so that the mask or the substrate accelerates to the target scanning speed at a constant acceleration. The acceleration does not discontinuously, that is, does not suddenly change at the end of the acceleration.
Accordingly, high-frequency vibration of at least one of the mask and the substrate caused by the rapid change of the acceleration can be suppressed, and the position error with respect to the target position (which naturally changes with time) can be quickly brought into the allowable range. The convergence can be achieved, and as a result, the synchronization settling time between the mask and the substrate can be reduced.

In this case, the substrate (W) or the mask (R) may be decelerated at a constant acceleration during the deceleration. In such a case, by setting the absolute value of the deceleration to a constant acceleration (negative acceleration) corresponding to the highest acceleration, the deceleration time can be significantly reduced, and the acceleration of the substrate or the mask from the start to the end of the deceleration can be achieved. Can be further reduced. In this case, at the end of the deceleration, there is no need to set the mask and the substrate synchronously. Therefore, there is no inconvenience even if the deceleration is performed at a constant acceleration. Here, both the substrate and the mask may be accelerated by the method of claim 41 and decelerated by the method of claim 42. In such a case, the throughput can be improved most.

43. The scanning exposure method according to claim 43, wherein the mask and the substrate are moved synchronously to transfer the pattern of the mask to one or more divided regions on the substrate. Prior to the synchronous exposure of the mask and the substrate, at least one of the mask and the substrate is moved in the synchronous movement direction based on an acceleration change curve such that the acceleration gradually converges to zero. It is characterized by accelerating along.

According to this, at the time of scanning exposure for each partitioned area, at least one of the mask and the substrate has an acceleration change curve whose acceleration gradually converges to zero prior to the synchronous movement between the mask and the substrate. Since the acceleration is performed in the synchronous movement direction based on the acceleration, the acceleration does not discontinuously, that is, does not suddenly change at the end of the acceleration as in the case of accelerating to the target scanning speed at a constant acceleration. Therefore, high-frequency vibration of at least one of the mask and the substrate caused by the rapid change of the acceleration can be suppressed,
The position error with respect to the target position (which naturally changes with time) can be quickly converged within an allowable range,
As a result, the synchronous settling time between the mask and the substrate can be reduced.

Here, when the mask and the substrate are accelerated along the synchronous movement direction based on the acceleration change curve as described above, the settling time can be shortened most, but usually, in a scanning exposure apparatus, , The maximum acceleration of one of the mask (mask stage) and the substrate (substrate stage) is a constraint, and if the above acceleration method is adopted for the one having the constraint, a sufficient effect can be obtained. Can be obtained.

In this case, as in the invention according to claim 44, the first partitioned area and the second partitioned area on the substrate are arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. When sequentially transferring the pattern of the mask to the partitioned area, the substrate may be decelerated in the first direction after the scanning exposure of the first partitioned area is completed, and the substrate may be transferred before the scanning exposure of the second partitioned area. During acceleration in one direction, the substrate may be moved in a direction intersecting the first and second directions. In such a case, as in the case of the twelfth aspect, the substrate is consequently moved along a path close to the shortest distance, so that the throughput can be further improved in combination with the shortening of the settling time.

The invention according to claim 45 is that the mask and the substrate are synchronously moved, and the first substrate on the substrate is arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method for sequentially transferring the pattern of the mask to the divided area and the second divided area, at least at least one of the mask and the substrate is used for the scanning exposure to the first divided area. Prior to the synchronous movement, the acceleration is accelerated along the first direction based on an acceleration change curve whose acceleration gradually converges to zero, and along the first direction at a constant deceleration after the completion of the synchronous movement. It is characterized by deceleration.

According to this, at the time of scanning exposure on the first partitioned area, at least one of the mask and the substrate is formed into an acceleration change curve such that the acceleration gradually converges to zero prior to the synchronous movement between the mask and the substrate. And accelerates along the first direction, and decelerates along the first direction at a constant deceleration after the end of the synchronous movement. For this reason,
Since the acceleration does not suddenly change as in the case of accelerating to the target scanning speed at a constant acceleration, at least one of the position error of the mask and the substrate is quickly converged to an allowable range, and as a result, the position of the mask and the substrate is reduced. In addition to shortening the synchronous settling time, the deceleration at the constant deceleration (normally the deceleration corresponding to the maximum acceleration) is performed at the time of deceleration after the end of the synchronous movement. The time required for deceleration can be shortened as compared with the case where it is performed. Therefore, in the scanning exposure of at least the first partitioned area, the total total time from the start of acceleration to the end of deceleration can be further reduced for at least one of the mask and the substrate.

Also in this case, a sufficient effect can be obtained by adopting the above-described acceleration control method for both the mask (mask stage) and the substrate (substrate stage), or at least one of which has a constraint. .

In the invention according to claim 45, as in the invention according to claim 46, during the deceleration of the substrate in the first direction after the completion of the scanning exposure of the first partitioned area and the second
The substrate may be moved in a direction intersecting the first and second directions during acceleration of the substrate in the first direction before scanning exposure of the partitioned area. In such a case, as in the case of the twelfth aspect, the substrate is consequently moved along a path which is close to the shortest distance. Is possible.

In the scanning exposure method according to any one of claims 3 to 46, as in the invention described in claim 47, the first direction in which the substrate (W) is synchronously moved and the second direction orthogonal to the first direction. Among them, at least in the second direction, it is desirable to control the position of the substrate by using the first measurement beam (RIX1) in a direction different from the second direction. In such a case, at least in the second direction (non-scanning direction), position control is performed using the first length measurement beam in a different direction. That is, since the position control in the second direction is performed using the first measurement beam obliquely intersecting with the synchronous movement direction, the stage having the reflecting surface in the direction orthogonal to the first measurement beam is performed. If it is possible to adopt a stage of any shape as a substrate stage, it is not necessary to use a rectangular stage such as a square or a rectangular shape, the degree of freedom in the design of the stage shape is improved,
As a result, the size of the substrate stage can be reduced.

In this case, the exposure operation may be performed while controlling the position of the substrate in the first direction (synchronous movement direction) using a length measurement beam in a direction different from the synchronous movement direction. As in the invention described in Item 48, it is preferable to control the position of the substrate (W) in the first direction using a second measurement beam (RIY) substantially parallel to the first direction. When the position control in both the synchronous movement direction and the non-scanning direction is performed using different length measurement beams from the respective directions, the position is controlled by a trigonometric function operation for position control in both the synchronous movement direction and the non-scanning direction. In the case of the present invention, such a trigonometric function operation is unnecessary in the synchronous movement direction (first direction).

In the scanning exposure method according to claim 47 or 48, as in the invention according to claim 49, the first length measuring beam (R) intersects the first and second directions and is different from the first and second directions.
The position of the substrate (W) may be controlled using a third measurement beam (RIX2) in a direction different from that of the substrate (W1). In this case, the third measurement beam may be used for controlling the position of the substrate in the first direction.
The measurement beam may be used for controlling the position of the substrate in the second direction. In such a case, the position measurement in the non-scanning direction can be performed independently of the position measurement in the scanning direction of the substrate, and the averaging effect enables high-precision measurement.
Calculations for position control are simplified, and more accurate substrate position control becomes possible.

The stage device according to the fiftyth aspect of the present invention is a stage device, comprising: a platen (22); at least two first plates which can move relative to the platen and respectively hold the substrates (W1, W2). 1 movable body (WST1, WST2)
A second movable body (138) in which each of the first movable bodies is arranged on the upper surface thereof, is arranged on the surface plate, and moves relative to each of the surface plate and each of the first movable bodies. ) Provided on the second movable body, and each of the first
A driving device (42a, 4a) for driving the movable body in a two-dimensional plane
2b), wherein the second movable body is configured to move in response to a reaction force when each of the first movable bodies is driven.

According to this, when any one of the first movable bodies is driven by the driving device, the second movable body moves by the reaction force of the driving force, and the center of gravity of the first movable body moves. The eccentric load can be canceled by moving the center of gravity of the second movable body, and as a result, the center of gravity of the entire stage device can be held at a predetermined position. Similarly, when a plurality of first movable bodies are simultaneously driven by the driving device, a biased load due to the movement of the center of gravity of the plurality of first movable bodies is caused by a reaction force corresponding to a resultant force of the driving forces. The second movable body moves so as to be canceled by the movement, and as a result, the center of gravity of the entire stage device can be held at a predetermined position. Accordingly, it is not necessary to adjust the operation of the first movable bodies so that the operation of a certain first movable body does not act as a disturbance on another first movable body, so that the control load is reduced and The position controllability of each first movable body can be kept high.

In this case, the mass of each of the first movable bodies (WST1, WST2) is substantially 1/9 or less of the mass of the second movable body (138). A second driving device (44) for driving the second movable body at a low response frequency on the surface plate (22) may be further provided. In such a case, as described above, the center of gravity of the stage device can be held at a predetermined position. In addition, for example, when one of the first movable bodies moves, the second movable body is moved in the opposite direction by the reaction force. The distance that the body moves is 1 /
It can be 10 or less. The second movable body is the first movable body.
Since the second driving device drives the movable body on the surface plate at a low response frequency that cannot respond to the reaction force at the time of acceleration / deceleration of the movable body, it does not affect the movement of each of the first movable bodies. , The second movable body can be driven.

According to a fifty-second aspect of the present invention, there is provided an exposure apparatus for transferring a mask pattern onto a substrate.
Or the stage device according to 51, wherein a substrate to which the pattern of the mask is transferred is held by each of the first movable bodies constituting the stage device.

In this case, when a projection optical system for projecting the pattern of the mask onto the substrate is further provided as in the invention according to claim 53, the driving device constituting the stage device includes When transferring the pattern of the mask onto the substrate held by each of the first movable bodies, the first holding unit holds the substrate to which the pattern is to be transferred.
A movable body may be driven in the scanning direction with respect to the projection optical system in synchronization with the mask.

According to a fifty-fourth aspect, the pattern of the mask (R) is transferred to each of the first and second partition regions (S1 and S2) arranged adjacent to each other on the substrate (W or W1). An exposure apparatus, comprising: a substrate stage (WST, WST1, or WST3) for holding the substrate; and moving the substrate stage between a first exposure for the first partitioned area and a second exposure for the second partitioned area. A first driving device ((42, 78) or (42a, 160)) for making the absolute value of the acceleration different between the time of acceleration and the time of deceleration of the substrate stage.

According to this, the first driving device for changing the transfer position of the mask pattern on the substrate between the first exposure for the first division area on the substrate and the second exposure for the second division area. Moves the substrate stage. At this time, in the first driving device, the absolute value of the acceleration is made different between when the substrate stage is accelerated and when the substrate stage is decelerated. Therefore, in the first driving device, the absolute value of the acceleration when the substrate stage is moved and the absolute value of the acceleration when the substrate stage is decelerated between the first exposure for the first partitioned region and the second exposure for the second partitioned region are determined. By appropriately setting the absolute value of the acceleration at the time of acceleration and deceleration at the same time, the positioning stabilization time of the substrate after the movement is shortened, and the It is possible to control the movement of the substrate stage such as shortening the total time required.

In this case, the first driving device ((42, 78) or (4)
2a, 160)), it is desirable to make the absolute value of the acceleration larger during the acceleration than during the deceleration. In such a case, the absolute value of the negative acceleration at the time of deceleration of the substrate stage before the start of the second scanning exposure is set to be small to effectively attenuate the vibration of the substrate stage at the end of the movement, thereby shortening the positioning settling time. Thus, the second exposure can be started immediately after the end of the movement. In addition, by increasing the absolute value of the acceleration when the substrate stage is accelerated after the end of the first exposure, the moving time is not unnecessarily prolonged. Therefore, it is possible to shorten the entire time including the movement and positioning settling time of the substrate stage, and to improve the throughput.

In the exposure apparatus according to each of the inventions, the substrate stage (WST, WST1 or WST
A first surface plate (38 or 138) on which 3) is arranged; and a second surface plate (22) on which the first surface plate is arranged.
The first platen may move relative to the substrate stage on the second platen in response to the movement of the substrate stage. In such a case, when the substrate stage moves, the first platen moves relative to the substrate stage on the second platen in response thereto. Since it is possible to cancel by moving the center of gravity of one surface plate, the center of gravity of the entire system including the substrate stage, the first surface plate, and the second surface plate can be held at a predetermined position.

In this case, as in the invention according to the fifty-seventh aspect, the second base plate (138) disposed on the first base plate (138).
When further including a substrate stage (WST2 or WST4), the first platen includes the two substrate stages (WST2 or WST4).
It is desirable that the movement is performed so as to cancel out the resultant force of the reaction forces generated by the movement of ST1, WST2 or WST3, WST4). In such a case, when the two substrate stages move at the same time, the first platen is moved so as to cancel the resultant force of the reaction force generated by the movement. That is,
The first platen moves so as to cancel the reaction force caused by the movement of the two substrate stages. As a result, the center of gravity of the entire system including the two substrate stages, the first platen and the second platen is held at a predetermined position. it can. Therefore, it is not necessary to adjust the operations of the substrate stages so that the operation of one substrate stage does not act as a disturbance on the other substrate stage, so that the control load is reduced and the position of each substrate stage is reduced. High controllability can be maintained.

In the exposure apparatus according to claim 56, as in the invention described in claim 58, the first platen (1)
38) When further comprising a second substrate stage (WST2 or WST4) disposed on the first substrate, the first platen is provided with the two substrate stages (WST1, WST2 or WST4).
3, WST4) may be moved so as to prevent a change in the position of the center of gravity due to the movement of at least one of WST4). In such a case, when any one of the substrate stages moves, the first base plate moves by a reaction force due to the movement, and the unbalanced load due to the movement of the center of gravity of the substrate stage is canceled by moving the center of gravity of the first base plate. As a result, the center of gravity of the entire system including the two substrate stages, the first platen and the second platen can be held at a predetermined position. Similarly, when two substrate stages are driven at the same time, the eccentric load due to the movement of the center of gravity of the two substrate stages is canceled by the movement of the center of gravity of the first platen by the reaction force corresponding to the resultant force of the driving forces. The first platen moves to the first stage, resulting in two substrate stages, the first
The center of gravity of the entire system including the surface plate and the second surface plate can be held at a predetermined position.

In the exposure apparatus according to each of the inventions described in claims 56 to 58, as in the invention described in claim 59,
A second driving device (44) for relatively moving the first surface plate (138) with respect to the second surface plate (22); and a control response of the second driving device (44) for exposing the substrate to an exposure operation. And a control device (160) that makes each variable by a plurality of operations including: In such a case, for example, it is necessary to control the position of the substrate stage with high precision, for example, in the case of exposure and alignment, the first platen needs to move in response to the reaction force due to the movement of the substrate stage. Therefore, the control device sets the control response of the second drive device so as not to follow the drive of the substrate stage by the first drive device. On the other hand, in an operation in which it is not necessary to perform the position control of the substrate with high accuracy, the control device uses the first control.
The control response of the second drive device is set such that the surface plate is not affected by the movement of the substrate stage and substantially maintains its position with respect to the second surface plate. Thereby, the required stroke of the first platen can be reduced.

In this case, as in the invention according to claim 60, the control device (160) controls the first base plate (138) when the substrate stage moves between the first and second exposures. However, the control response of the second drive device (44) may be set so that control can be performed so as to substantially maintain the position with respect to the second platen (22).

In the exposure apparatus according to each of the inventions as set forth in claims 54 to 60, as in the invention as set forth in claim 61,
The first driving device ((42, 78) or (42a, 16)
In 0)), the substrate stage may be moved so that a plurality of partitioned areas on the substrate are exposed by a step-and-repeat method or a step-and-scan method. That is, in the case of such a sequential movement type exposure apparatus,
Stepping the substrate stage (positioning the substrate stage with respect to the transfer position of the mask pattern (in the case of the step-and-repeat method), or moving the substrate stage to the scan start position for transferring the mask pattern to each partitioned area on the substrate (In the case of the step-and-scan method)) is repeated, so that the above-described improvement in the position controllability of the substrate stage contributes to a reduction in the overall exposure time.

In the exposure apparatus according to any one of claims 54 to 61, as in the invention described in claim 62, the first drive unit drives the substrate stage with at least three degrees of freedom. Type linear actuator (4
2, or 42a, 42b). Here, when the first planar magnetic levitation linear actuator drives the substrate stage with, for example, three degrees of freedom in a moving plane, by combining with an appropriate Z-tilt mechanism,
The position and orientation of the substrate stage in six degrees of freedom can be controlled. Also, for example, when the first planar magnetic levitation linear actuator drives the substrate stage in six degrees of freedom, the position and orientation of the substrate stage in the six degrees of freedom are controlled by the first planar magnetic levitation linear actuator. Since the control can be performed, the configuration of the substrate stage can be simplified and reduced in weight, for example, by configuring the substrate stage with a simple plate-like member.

In the exposure apparatus according to each of the inventions as set forth in claims 59 to 62, as in the invention as set forth in claim 63,
The second drive device may include a second planar magnetic levitation linear actuator (44) that moves the first platen (138) relative to the second platen (22).

The invention according to claim 64 is a mask (R)
An exposure apparatus for transferring the pattern of (1) onto a substrate (W1, W2), comprising: a first surface plate (138); and a plurality of substrate stages each holding the substrate respectively disposed on the first surface plate ( WST1, WST2 or WST3, WST
4) and; a second platen (22) on which the first platen is arranged.
And a support device (44) for supporting the first platen so as to be relatively movable with respect to the second platen so as to suppress a change in the position of the center of gravity due to the movement of at least one of the plurality of substrate stages. . In such a case, when any one of the substrate stages moves, the first platen supported by the support device moves due to the reaction force due to the movement, and the unbalanced load due to the movement of the center of gravity of the substrate stage moves. Cancellation can be made by moving the center of gravity, and as a result, the center of gravity of the entire system including the plurality of substrate stages, the first surface plate, and the second surface plate can be held at a predetermined position. Similarly, when the plurality of substrate stages move at the same time, the unbalanced load due to the movement of the center of gravity of the plurality of substrate stages is canceled by the movement of the center of gravity of the first platen due to the resultant reaction force generated by the movement of each of the substrate stages. Thus, the first platen supported by the support device is moved, and as a result, the center of gravity of the entire system including the plurality of substrate stages, the first platen, and the second platen can be held at a predetermined position. Therefore, it is not necessary to adjust the operations of the substrate stages so that the operation of one substrate stage does not act as a disturbance on the other substrate stages, so that the control load is reduced and the position of each substrate stage is reduced. High controllability can be maintained together

In this case, the first substrate stage (WST1 or WST3) among the plurality of substrate stages may be configured such that the substrate (W1) is a step-and-repeat type or a step-and-repeat type. When moved to be exposed in the AND scan method,
The support device may include a planar magnetic levitation linear actuator that supports the first surface plate (138) so as to be relatively movable with respect to the second surface plate (22). In the case of such a sequential movement method, stepping of the first substrate stage (positioning of the first substrate stage with respect to the transfer position of the mask pattern (in the case of the step-and-repeat method)) or transfer of the mask pattern to each partitioned area on the substrate. Of the first substrate stage to the scanning start position (in the case of the step-and-scan method) is repeatedly performed, so that the above-described improvement in the controllability of the position of the first substrate stage contributes to shortening of the entire exposure time. The rate of doing it increases.

In this case, the first substrate stage (WST1 or WST1) may be connected to the first substrate stage (WST1 or WST1).
3) During the exposure operation of the upper substrate (W1), a second substrate stage (WST2 or WST) different from the first substrate stage
4) may be driven so that operations other than the exposure operation are performed. In such a case, on the first substrate stage and the second
Since the exposure operation and other operations are simultaneously and concurrently processed on the substrate stage, the overall throughput can be improved. Further, the operation of the first substrate stage does not act as a disturbance on the second substrate stage.

In this case, during the exposure operation of the substrate on the first substrate stage, an alignment system (124) for detecting a mark on the substrate as in the invention according to claim 67,
a, 124b), wherein the second substrate stage (W
In ST2 or WST4), mark detection by the alignment system, or loading or unloading of the substrate may be executed.

In the exposure apparatus according to each of the inventions described in claims 54 to 67, as in the invention described in claim 68,
The first and second substrate stages (WST3, WST4) are arranged such that their extending directions cross each other at an acute angle.
It may further include first and second interferometers having reflecting surfaces (60a and 60b (or 60c)) and having length measuring axes orthogonal to the first and second reflecting surfaces, respectively. According to this, at least one of the first reflection surface and the second reflection surface extends in a direction intersecting any one of the coordinate axes of the rectangular coordinate system except at a right angle.
Compared to a substrate stage having an axial reflecting surface, the beam of the interferometer continues to travel for a longer time when moving in any coordinate axis direction of the above-described orthogonal coordinate system. Therefore, for example, even in the case of a stationary exposure apparatus such as a stepper, by arranging an aerial image measuring instrument, a reference mark, and the like at the end of the substrate stage,
When measuring while moving the stage, the measurement can be performed without extending the reflective surface in the direction that intersects any one of the coordinate axes of the rectangular coordinate system in consideration of the approach distance during the movement. This makes it possible to improve the degree of freedom in arranging reference marks and the like. In this sense, it is desirable that both the first reflection surface and the second reflection surface intersect with a predetermined coordinate axis of the rectangular coordinate system.

In this case, the first and second reflecting surfaces (60a and 60b)
(Or 60c)) is desirably arranged so that a trapezoid having the two reflecting surfaces on two sides other than the upper bottom and the lower bottom includes the substrate. Here, the trapezoid is a concept including the upper base = 0, that is, including a triangle. In this case, it is more desirable that the trapezoid circumscribes the substrate.

In each of the inventions described in claims 68 and 69, as in the invention described in claim 70, the first and second reflection surfaces substantially cover the substrate on the substrate stage (WST), respectively. It may be formed along two sides of the triangle.

In the exposure apparatus according to each of the inventions according to claims 68 to 70, as in the invention according to claim 71,
It is preferable that the length in the extending direction of the first reflecting surface or the second reflecting surface is set substantially longer than the exposure range on the substrate. Here, "substantially long" means that the first reflecting surface and the second reflecting surface are not necessarily a series of reflecting surfaces, but a plurality of reflecting mirrors arranged adjacent to each other with a predetermined clearance in the extending direction. In such a case, the total length in the extending direction is longer than the exposure range. The “exposure range” means the range of the area where the pattern of the mask is to be transferred onto the substrate when the area is one area. If there is an area, as in the invention of claim 72,
The exposure range includes all partial regions where the pattern of the mask (R) is to be transferred on the substrate.

In the exposure apparatus according to each of the inventions described in claims 54 to 67, as in the invention described in claim 73,
A mask stage (RST) for holding the mask; and a mask stage and the substrate stage (WST3, WST) for transferring the pattern of the mask onto the substrate.
And 4) synchronously moving in a first direction, wherein the substrate stage comprises a first length measuring first extending along a direction intersecting at an acute angle with the synchronously moving first direction.
It may have a reference plane (60a).

In this case, for example, the first direction and the first
Assuming that the angle formed by the reference plane is 面 and the length of the first reference plane for length measurement is L, the first direction component L1 of the first reference plane for length measurement is L
cosΘ. In other words, considering the case where the substrate stage moves in the first direction, the length L1 extending in the first direction is considered.
The length measuring beam continues to hit the first reflecting surface for a time (moving distance) longer by 1 / cosΘ (> 1) times than that of the reflecting surface, and is not cut off. Accordingly, if at least the position of the substrate stage (substrate) in the non-scanning direction is controlled using the first reference plane for length measurement, the exposure of the area around the substrate as in the case of the conventional position control of the square stage is performed. Even if the first reference plane for length measurement is not extended further in anticipation of the so-called pre-scan or over-scan distance at the time of
Position control in a second direction (non-scanning direction) orthogonal to the first direction can be performed over the entire moving stroke in the direction. Therefore, the size of the substrate stage can be reduced.

In this case, as in the invention according to claim 74, the first reference plane (60a) extends over substantially the entire moving range of the substrate stage in the scanning exposure operation of the substrate in the extending direction. It is desirable to be formed. In such a case, the beam for length measurement does not deviate from the first reference plane for length measurement during the scanning exposure operation of the substrate. Therefore, the beam is orthogonal to the first direction over the entire moving stroke of the substrate stage in the first direction. Position control in the second direction (non-scanning direction) becomes possible

[0097] In the exposure apparatus according to each of the above aspects 73 and 74, as in the invention according to aspect 75, the first reference surface (60a) has a length in the extending direction on the substrate. Is desirably set substantially longer than the exposure range. In this case, the exposure range means the range of the area to be scanned and exposed on the substrate when the area is one area, and when the area to be scanned and exposed is plural on the substrate, 76, the exposure range includes all the divided areas where the pattern of the mask (R) is to be transferred on the substrate (W).

In the exposure apparatus according to each of the above-described aspects of the present invention, as in the above-described aspect,
A length measurement axis (R) orthogonal to the first length reference plane (60a)
IX1) further comprising a first interferometer (76X1), wherein the measured value of the first interferometer is at least a second direction of the first direction and a second direction orthogonal to the first direction. It may be used for stage position control. In such a case, the measurement value of the first interferometer having the length measurement axis orthogonal to the first length measurement reference plane is used for position control of the substrate stage (substrate) in the second direction (non-scanning direction). Therefore, as in the case of the position control of the conventional square stage, the first reference plane for length measurement can be extended without extra length in anticipation of the so-called pre-scan or over-scan distance when exposing the area around the substrate. A second direction (non-scanning direction) orthogonal to the first direction over the entire movement stroke in one direction
Can be controlled. Therefore, the size of the substrate stage can be reduced.

In the exposure apparatus according to each of the inventions as set forth in claims 73 to 77, as in the invention according to claim 78,
The substrate stage may include a second length measurement reference plane (60b) extending in a second direction orthogonal to the first direction.

The position of the substrate stage can be controlled not only in the second direction but also in the first direction based on the measurement value of the first interferometer. , A trigonometric function operation is required to determine the respective positions in the second direction. On the other hand, in the case of the present invention, such a trigonometric function operation is not required for the first direction by using the second reference plane for length measurement for position control of the substrate stage in the first direction. In this sense, as in the invention according to claim 79, the second reference plane for length measurement (6)
0b) and a second interferometer (76)
Preferably, the method further comprises Y), wherein the measurement value of the second interferometer is used for controlling the position of the substrate stage in the first direction.

In the exposure apparatus according to each of the inventions as set forth in claims 73 to 79, as in the invention as set forth in claim 80,
The substrate stage intersects both the first direction and a second direction orthogonal thereto, and has a third measurement reference plane (60c) in a direction different from the first measurement reference plane (60a).
It is desirable to have. In such a case, the third reference plane for length measurement can be used for position measurement of one or both of the first and second directions of the substrate stage. In particular, when the third reference plane for measurement is used together with the reference plane for first measurement for position measurement of the substrate stage, highly accurate position measurement by the averaging effect and, consequently, high-precision position control become possible. . In this sense, as in the invention according to Claim 81, the apparatus further comprises a third interferometer (76X2) having a length measurement axis (RIX2) orthogonal to the third length measurement reference plane (60b). 3
It is desirable to use the measurement value of the interferometer of (1) for position control of the substrate stage in at least one of the first and second directions.

[0102]

DESCRIPTION OF THE PREFERRED EMBODIMENTS << First Embodiment >> A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view of a scanning type exposure apparatus 10 according to a first embodiment of the present invention, and FIG.
2 schematically shows the internal configuration. The scanning exposure apparatus 10 is a projection exposure apparatus that performs an exposure operation by a step-and-scan method, which is currently becoming the mainstream as a lithography apparatus for manufacturing semiconductor elements. The scanning exposure apparatus 10 projects a partial image of a circuit pattern drawn on a reticle R (see FIG. 2) as a mask onto a wafer W as a sensitive substrate (or a substrate) via a projection optical system PL. While moving the reticle R and the wafer W in a one-dimensional direction with respect to the visual field of the projection optical system PL (here, Y
Direction), the entire circuit pattern of the reticle R is transferred to each of a plurality of shot areas on the wafer W by a step-and-scan method.

As shown in FIG. 1, the scanning exposure apparatus 10 includes an excimer laser light source 11 and an exposure apparatus main body 1.
2 and a control rack 14 as a main control system for integrally controlling them. The excimer laser light source 11 is installed in another room (a low-clean service room) isolated from the ultra-clean room where the exposure apparatus main body 12 is usually installed. Further, the exposure apparatus body 12
Is usually installed in an ultra-clean room, the interior space is highly dustproof, and is housed in an environmental chamber with high-precision temperature control.
FIG. 1 schematically shows only the main body structure housed in the chamber.

Next, the configurations of the excimer laser light source 11, the exposure apparatus main body 12, and the control rack 14 will be described with reference to FIGS.

The excimer laser light source 11 has an operation panel 11A. Also, the excimer laser light source 11
Has a built-in control computer 11B (not shown in FIG. 1; see FIG. 2) for interfacing with the operation panel 11A. The pulse emission of the excimer laser light source 11 is controlled in response to a command from a main controller 50 composed of a minicomputer.

The excimer laser light source 11 is used as an exposure light source, and emits, for example, KrF excimer laser light having a wavelength of 248 nm or ArF excimer laser light having a wavelength of 193 nm. Here, the pulse laser light in the ultraviolet region from the excimer laser light source 11 (hereinafter also referred to as "excimer laser light", "pulse illumination light" or "pulse ultraviolet light" as appropriate) is used as the illumination light for exposure at 256M. The minimum line width required for mass production of microcircuit devices having a degree of integration and fineness equivalent to a semiconductor memory element (D-RAM) of 4 to 4 Gbit class or more.
This is for obtaining a pattern resolution of about 25 to 0.10 μm.

The pulse laser light (excimer laser light)
Is narrowed so that chromatic aberration caused by various refractive optical elements constituting the illumination system and the projection optical system PL of the exposure apparatus is within an allowable range. The absolute value of the center wavelength to be narrowed and the value of the narrowing width (between 0.2 pm and 300 pm) are displayed on the operation panel 11A,
Fine adjustment can be made from the operation panel 11A as needed. A mode of pulse emission (typically, three modes of self-excited oscillation, external trigger oscillation, and maintenance oscillation) can be set from the operation panel 11A.

As described above, an example of an exposure apparatus using an excimer laser as a light source is disclosed in JP-A-57-198631.
JP-A-1-259533, JP-A-2-13572
An example of an exposure apparatus disclosed in Japanese Unexamined Patent Application Publication No. 3 and Japanese Patent Application Laid-Open No. H2-294013 and using an excimer laser light source for step-and-scan exposure is disclosed in Japanese Unexamined Patent Application Publication No. HEI 2-2294.
No. 23, JP-A-6-132195, JP-A-7
No. 142542. Therefore, FIG.
In the scanning exposure apparatus 10 described above, the basic technology disclosed in each of the above-mentioned patent publications can be applied as it is or partially modified.

The exposure apparatus body 12 includes a gantry 16, a reticle stage RST, an illumination optical system 18, and a projection optical system P.
An L / LC / MAC system, a stage device 1, a wafer transfer robot 19, an alignment system, and the like are provided.

More specifically, as shown in FIG. 1, the gantry (first gantry) 16 is supported on the floor via four vibration isolation devices 20. Each anti-vibration device 20
The weight of the exposure apparatus main body 12 is supported via an air cylinder (vibration isolation pad) (not shown).
Are provided with an actuator and various sensors for actively correcting the displacement in the X and Y directions by feedback control or feedforward control by a control system (not shown). An active vibration isolator of this type is disclosed in, for example, Japanese Patent Application Laid-Open No. 9-74061.

The gantry 16 has a surface plate 22 parallel to the floor surface and a support plate portion 24 provided above and opposed to the surface plate 22, and has a box-like shape with a hollow inside. ing. The support plate 24 is formed of a rectangular plate-like member having a circular opening formed in the center, and the projection optical system PL is inserted into the center opening in a state orthogonal to the support plate 24. The projection optical system PL is held by the support plate 24 via a flange provided on a part of the outer periphery.

On the upper surface of the support plate 24, the projection optical system PL
The four legs 26 are erected so as to surround. A reticle base platen 28 supported by the four legs 26 and interconnecting the upper ends thereof is provided above the four legs 26. These four legs 2
6 and the reticle base platen 28 constitute a second column (second base).

On the upper surface of the reticle base platen 28, a guide 28b extends in the Y direction (first axial direction, first direction). An opening 28a (see FIG. 2) is formed in the center of the reticle base surface plate 28. The emission end of the illumination optical system 18 is arranged to face the opening 28a.

On the reticle base surface plate 28, the reticle stage RST is provided which holds the reticle R by suction and moves in the Y direction along the guide 28b. The reticle stage RST is driven by a linear motor or the like constituting a drive system 29 (see FIG. 2). The reticle stage RST linearly moves on the reticle base surface plate 28 with a large stroke in the Y direction, and moves in the X direction. (The second axial direction, the second direction) and the θ direction can be minutely driven by a voice coil motor (VCM), a piezo element, or the like.

FIG. 2 shows a part of reticle stage RST.
As shown in FIG. 1, a movable mirror 31 for reflecting a length measurement beam from a reticle laser interferometer 30 for measuring the position and the amount of movement is attached. Where, in practice,
The reticle laser interferometer is composed of a reticle Y interferometer for Y-direction (scanning direction) position measurement and a reticle X for X-direction position measurement.
An interferometer and a reticle θ interferometer for measuring the θ direction (rotation direction) are provided, and a movable mirror corresponding to each of the interferometers is fixed on a reticle stage RST. Is typically a reticle laser interferometer 3
0, shown as a moving mirror 31. Then, the X, Y, and θ directions of the reticle stage RST are measured by the above three reticle interferometers, respectively.
It is assumed that the position measurement in the Y and θ directions is simultaneously and individually performed.

The position information (or speed information) of reticle stage RST (that is, reticle R) measured by interferometer 30 is sent to reticle stage controller 33. The reticle stage controller 33 basically includes a drive system (linear motor) for moving the reticle stage RST such that the position information (or speed information) output from the interferometer 30 matches the command value (target position, target speed). , A voice coil motor, a piezo motor, etc.) 29.

As shown in FIG. 1, the illumination optical system 18 has a beam receiving system 32 housed in the back thereof and a BMU comprising the beam receiving system 32 and a light-shielding tube 34 connected thereto. (Beam matching unit) is connected to the excimer laser light source 11. Excimer laser light from the excimer laser light source 11 guided through the tube 34 always enters the beam receiving system 32 constituting the BMU with a predetermined positional relationship with respect to the optical axis of the illumination optical system 18. As described above, a plurality of movable reflecting mirrors (not shown) for optimally adjusting the incident position and the incident angle of the excimer laser light to the illumination optical system 18 are provided.

As shown in FIG. 2, the illumination optical system 18 includes a variable dimmer 18A, a beam shaping optical system 18B,
Fly-eye lens system 18C, vibrating mirror 18D, condenser lens system 18E, illumination NA correction plate 18F, second fly-eye lens system 18G, illumination system aperture stop plate 18H, mirror 18
J, a first relay lens 18K, a fixed reticle blind 18L, a movable reticle blind 18M, a second relay lens 18N, an illumination telecentric correction plate (parallel plate of tiltable quartz) 18P, a mirror 18Q, and a main condenser lens system 18R. Have. Here, the components of the illumination optical system 18 will be described.

The variable dimmer 18A is for adjusting the average energy of each pulse of the excimer laser light. And an optical filter that continuously varies the dimming rate by adjusting the degree of overlap between two optical filters whose transmittance continuously changes. The optical filter constituting the variable dimmer 18A includes a drive mechanism 35 controlled by the main controller 50.
Driven by

The beam shaping optical system 18B includes the variable dimmer 1
The cross-sectional shape of the excimer laser beam adjusted to a predetermined peak intensity by 8A is incident on a first fly-eye lens system 18C which is provided behind the optical path of the excimer laser beam and constitutes an incident end of a double fly-eye lens system described later. It is shaped so as to be similar to the entire shape of the end and is efficiently incident on the first fly-eye lens system 18C, and is composed of, for example, a cylinder lens and a beam expander (both not shown).

The double fly-eye lens system is for uniformizing the intensity distribution of the illumination light, and the first fly-eye lens system is sequentially arranged on the optical path of the excimer laser light behind the beam shaping optical system 18B. 18C and the condenser lens 18
E and a second fly-eye lens system 18G. In this case, between the first fly-eye lens system 18C and the condenser lens 18E, a vibrating mirror 18D for smoothing interference fringes and weak speckles generated on the irradiated surface (reticle surface or wafer surface) is provided. Are located. The vibration (deflection angle) of the vibration mirror 18D is controlled by the main controller 50 via the drive system 36.

On the incident end side of the second fly lens system 18G, the directionality of the numerical aperture (illumination N
The illumination NA correction plate 18F for adjusting the (A difference) is arranged.

For a configuration in which the double fly-eye lens system and the vibrating mirror 18B are combined as in the present embodiment, for example, Japanese Patent Application Laid-Open Nos.
No. 142354 discloses this in detail.

An illumination system aperture stop plate 18 made of a disc-shaped member is provided near the exit surface of the second fly-eye lens system 18G.
H is arranged. The illumination system aperture stop plate 18H is provided at substantially equal angular intervals, for example, an aperture stop composed of a normal circular aperture, an aperture stop composed of a small circular aperture, for reducing the σ value which is a coherence factor, and an annular aperture. A ring-shaped aperture stop, a modified aperture stop formed by eccentrically arranging four apertures, and the like for the modified light source method are arranged. The illumination system aperture stop plate 18H is rotated by a motor (not shown) or the like controlled by the main controller 50, whereby any one of the aperture stops is selectively placed on the optical path of the pulse illumination light. It is set, and the light source surface shape in Koehler illumination is limited to an annular zone, a small circle, a large circle, a fourth circle, or the like.

A beam splitter 18J having a large reflectance and a small transmittance is arranged on the optical path of the pulse illumination light behind the illumination system aperture stop plate 18H.
A relay optical system including a first relay lens 18K and a second relay lens 18N is arranged with a fixed reticle blind 18L and a movable reticle blind 18M interposed therebetween.

The fixed reticle blind 18L is arranged on a plane slightly defocused from a conjugate plane with respect to the pattern plane of the reticle R, and has an opening having a predetermined shape that defines an illumination area on the reticle R. In the present embodiment, it is assumed that the opening is formed in a slit shape or a rectangular shape linearly extending in the X direction orthogonal to the moving direction (Y direction) of the reticle R during scanning exposure.

A movable reticle blind 18M having an opening whose position and width in the scanning direction is variable is arranged near the fixed reticle blind 18L, and illumination is performed via the movable reticle blind 18M at the start and end of scanning exposure. By further restricting the area, exposure of an unnecessary portion is prevented. The movable reticle blind 18M is controlled by the main controller 50 via the drive system 43.

At the exit of the second relay lens 18N constituting the relay optical system, an illumination telecentric correction plate 18P is arranged, and further on the optical path of the pulse illumination light behind the second relay lens 18N, A mirror 18Q that reflects the pulsed illumination light passing through the illumination telecentric correction plate 18P toward the reticle R is disposed, and the main condenser lens system 18 is disposed on the optical path of the pulsed illumination light behind the mirror 18Q.
R is arranged.

The illumination optical system 18 thus configured
When the excimer laser light from the excimer laser light source 11 is incident on the illumination optical system 18 via the tube 34 and the beam receiving system 32, the excimer laser light is given a predetermined amount by the variable dimmer 18A. After being adjusted to the peak intensity, the light enters the beam shaping optical system 18B. The excimer laser light is applied to the beam shaping optical system 18B.
Thus, the cross-sectional shape is shaped so as to efficiently enter the rear first fly-eye lens system 18C. Next, when this excimer laser light is incident on the first fly-eye lens system 18C, a number of secondary light sources are formed on the exit end side of the first fly-eye lens system 18C. The pulsed ultraviolet light diverging from each of these many point light sources passes through the vibrating mirror 18D, the condenser lens system 18E, and the illumination NA correction plate 18F to the second.
The light enters the fly-eye lens system 18G. As a result, a large number of secondary light sources are formed at the exit end of the second fly-eye lens system 18G. The pulsed ultraviolet light emitted from the many secondary light sources passes through one of the aperture stops on the illumination system aperture stop plate 18H, and then reaches a beam splitter 18J having a large reflectance and a small transmittance.

The pulsed ultraviolet light as exposure light reflected by the beam splitter 18J is applied to the first relay lens 18
K illuminates the opening of the fixed reticle blind 18L with a uniform intensity distribution. However, interference fringes and weak speckles depending on the coherence of the pulsed ultraviolet light from the excimer laser light source 11 can be superimposed on the intensity distribution with a contrast of about several percent. For this reason, exposure unevenness due to interference fringes and weak speckles may occur on the wafer surface. The vibration mirror 18D is synchronized with the movement of the wafer W and the oscillation of the pulsed ultraviolet light.
Is smoothed.

The pulsed ultraviolet light that has passed through the opening of the fixed reticle blind 18L passes through the movable reticle blind 18M, passes through the second relay lens 18N and the illumination telecentric correction plate 18P, and the optical path is vertically moved downward by the mirror 18Q. After being bent into a predetermined shape, a predetermined illumination area (a slit-shaped or rectangular illumination area linearly extending in the X direction) on the reticle R held on the reticle stage RST is made uniform through the main condenser lens system 18R. Illumination with a suitable illuminance distribution. Here, the rectangular slit-shaped illumination light applied to the reticle R is set so as to extend in the X direction (non-scanning direction) in the center of the circular projection field of view of the projection optical system PL in FIG. Y direction (scanning direction)
Is set almost constant.

On the other hand, the pulsed illumination light transmitted through the beam splitter 18J is incident on an integrator sensor 46 composed of a photoelectric conversion element via a not-shown condenser lens, where it is photoelectrically converted. Then, the photoelectric conversion signal of the integrator sensor 46 is supplied to the main controller 50 via a peak hold circuit and an A / D converter, which will be described later.
As the integrator sensor 46, for example, a PIN-type photodiode or the like having sensitivity in the deep ultraviolet region and having a high response frequency for detecting pulse emission of the excimer laser light source 11 can be used. The correlation coefficient between the output of the integrator sensor 46 and the illuminance (exposure amount) of the pulsed ultraviolet light on the surface of the wafer W is obtained in advance and stored in the memory in the main controller 50.

As the projection optical system PL, here,
Both the object plane (reticle R) side and the image plane (wafer W) side are telecentric and have a circular projection visual field, and are only composed of a refractive optical element (lens element) using quartz or fluorite as an optical glass material. A refracting optical system with a (or 1/5) reduction magnification is used. An imaging light flux from a portion of the circuit pattern area on reticle R illuminated with the pulsed ultraviolet light is electrostatically attracted to a holder on wafer stage WST to be described later via projection optical system PL. The resist is projected onto the resist layer on W at a reduced size of 1/4 or 1/5.

Note that the projection optical system PL is described in Japanese Patent Laid-Open No. 3-282.
As disclosed in Japanese Unexamined Patent Publication No. 527, a so-called catadioptric system combining a refractive optical element and a reflective optical element (a concave mirror, a beam splitter, or the like) may be used.

The LC / MAC system finely adjusts various optical characteristics (imaging performance) of the projection optical system PL. In this embodiment, the LC / MAC system is provided at a position near the object plane in the projection optical system PL. Telecentric lens system G2 capable of minute movement in the axial direction and slight inclination with respect to the plane orthogonal to the optical axis, and this lens system G
Drive mechanism 96 for finely moving 2 in the optical axis direction (including the inclination)
And pressurizing and reducing the gas pressure in a specific air space (sealed chamber) sealed from the outside air in the projection optical system PL through a pipe 94 within a range of, for example, about ± 20 mmHg. And a lens controller 102 for finely adjusting the imaging magnification of the projected image. The MAC can adjust the magnification or distortion of the projected image (isotropic distortion, or anisotropic distortion such as barrel, pincushion, trapezoid, etc.).

In this case, the lens controller 102 also serves as a control system for the driving mechanism 96 of the lens system G2, and changes the magnification of the projected image by driving the lens system G2, or changes the pressure of the sealed chamber in the projection optical system PL. Switching control is performed to change the magnification of the projection image by control, or combined control is performed. The lens controller 102 is also under the control of the main controller 50.

However, when an ArF excimer laser light source having a wavelength of 193 nm is used as the illumination light, the inside of the illumination optical path and the inside of the barrel of the projection optical system PL are replaced with nitrogen gas or helium gas. Since it is difficult to change the refractive index in the specific air space, the mechanism for increasing or decreasing the pressure in the air space may be omitted.

Further, at a position near the image plane in the projection optical system PL, ascoma aberration, which is particularly likely to occur in a portion of the projected image having a particularly high image height (a portion near the periphery in the projection visual field), is reduced. And an as-coma aberration correcting plate G3 for causing the image to be corrected.

Further, in this embodiment, in order to effectively reduce a random distortion component contained in a projected image formed in an effective image projection area (defined by the opening of the fixed reticle blind 18L) in the circular visual field. The image distortion correction plate G1 is disposed between the reticle R and the lens system G2 of the projection optical system PL. The correction plate G1 locally polishes the surface of a parallel quartz plate having a thickness of about several millimeters and slightly deflects an image forming light beam passing through the polished portion. An example of how to make such a correction plate G1 is disclosed in detail in JP-A-8-203805.
Also in the present embodiment, basically, the technique disclosed in the publication is applied.

Next, the stage device 1 will be described.
As shown in FIGS. 1 and 2, the stage device 1 includes a platen 22
A movable surface plate 38 supported on the surface plate 22 so as to be relatively movable in the XY plane; and a movable surface plate 38 on the movable surface plate 38 relative to the movable surface plate 38 in the XY plane. And a wafer stage WST as a substrate stage supported by the wafer stage.

The wafer stage WST includes a projection optical system PL
The first planar magnetic levitation linear actuator 42 (see FIG. 5B) provided below the movable platen 38 and levitation supported, and the optical axis A of the projection optical system PL.
It is designed to be freely driven in an XY two-dimensional plane orthogonal to X. Similarly to wafer stage WST, movable platen 38 is levitated and supported by a second planar magnetic levitation linear actuator 44 (see FIG. 5B) provided on platen 22, and XY2 It is designed to be driven freely in a three-dimensional plane. In FIG. 2, the planar magnetic levitation linear actuators 42 and 44 are collectively shown as a drive system 48 for convenience of illustration. The drive system 48, that is, the planar magnetic levitation linear actuators 42 and 44 are controlled by a wafer stage controller 78. The control method and role of the movable surface plate 38 will be described later in detail.

The wafer stage WST is, as shown in FIG. 1, a movable stage 52 as a second plate which can be freely moved on a movable platen 38 in an XY two-dimensional plane.
A leveling drive mechanism 58 as a drive mechanism mounted on the moving stage 52; and a substrate table TB as a first plate supported by the leveling drive mechanism 58 and holding the wafer W.

In the present embodiment, the moving stage 52 is formed in a regular triangular shape, and one end surface thereof has a reticle stage RS.
Y-axis direction, which is the scanning direction of T (first direction, first axis direction)
Are arranged on the movable platen 38 in a direction orthogonal to the table.

The substrate table TB includes a moving stage 5
2 and is supported by three actuators ZAC constituting a leveling drive mechanism 58 in a state of overlapping with the moving table 52 in a plan view. A substantially circular wafer holder 54 is provided on the substrate table TB (see FIG. 3C), and the wafer W is electrostatically attracted to the wafer holder 54 and is held after being flattened and corrected. The temperature of the wafer holder 54 is controlled in order to suppress expansion deformation due to heat accumulation of the wafer W during exposure.

The leveling drive mechanism 58 supports three actuators (piezo, piezo, Voice coil motor, etc.) ZACX1, ZACX2, ZACY (see FIG. 3 (A)) and these three actuators ZAC
The actuator controller 56 is configured to finely move the substrate table TB in the direction of the optical axis AX (Z direction) by independently controlling X1, ZACX2, and ZACY, and to tilt the substrate table TB with respect to the XY plane. A drive command to the actuator control device 56 is output from the wafer stage controller 78.

Although illustration is omitted in FIG. 2,
A focus / leveling sensor for detecting a deviation (focus error) and an inclination (leveling error) in the Z direction between the imaging plane of the projection optical system PL and the surface of the wafer W is provided near the projection optical system PL, and the wafer stage controller 78 is provided. Outputs a drive command to the actuator control device 56 in response to a focus error signal or a leveling error signal from the sensor. An example of such a focus / leveling detection system is disclosed in detail in JP-A-7-201699.

The positions of the wafer stage WST, that is, the directions of the interferometer beams in FIG. 3A on the substrate table TB are sequentially measured by the laser interferometer system 76 shown in FIG. 78. Wafer stage controller 78
Calculates a XY coordinate position by a predetermined calculation, and outputs a command signal for driving wafer stage WST to drive system 48 based on the obtained coordinate position and target position information to be positioned.

Here, a specific configuration of the laser interferometer system 76 will be described in detail with reference to FIGS.

FIG. 3A shows a laser interferometer system 7.
First to third interferometers 76X1, 76Y, 7 that constitute 6
6X2 and interferometer beams RI from those three interferometers
X1, RIY, RIX2 are shown in plan view together with the substrate table TB.

As can be seen from FIG. 3A, in the present embodiment, the substrate table TB is formed in an equilateral triangle shape in plan view, and the three side surfaces thereof are mirror-finished to form the first to the first. Three reflecting surfaces 60a, 60b, 60c are formed. Then, the second interferometer 76Y vertically irradiates the second reflection surface 60b with the interferometer beam RIY in the Y-axis direction (first axis direction) that is the scanning direction, and receives the reflected light, thereby obtaining the substrate. The position (or speed) of the table TB in the Y-axis direction is measured. Further, the first interferometer 76X1 has a predetermined angle θ1 (θ1
Here is -60 °) interferometer beam RI in a tilted direction
By irradiating X1 perpendicularly to the first reflecting surface 60a and receiving the reflected light, the position (or speed) in the third axial direction which is the direction of the interferometer beam RIX1 is measured. Similarly, the third interferometer 76X2 vertically irradiates an interferometer beam RIX2 in a direction inclined at a predetermined angle θ2 (θ2 is + 60 ° here) with respect to the Y-axis direction to the third reflecting surface 60c, and reflects the beam. By receiving the light, the position (or speed) in the fourth axis direction which is the direction of the interferometer beam RIX2 is measured.

By the way, in consideration of the fact that a minute rotation error (including a yawing component) which can be generated in the XY plane due to the XY movement of the wafer stage WST or the fine movement of the substrate table TB has a bad influence on the exposure accuracy, this embodiment is not limited to this embodiment. As each interferometer constituting the laser interferometer system 76, a multi-axis interferometer is used.

FIG. 3B shows the interferometer beam RIY from the second interferometer 76Y in more detail together with some optical systems constituting the interferometer. As shown in FIG. 3B, the second reflection surface 60b of the substrate table TB
Include _first and second measurement beams RIY ₁ , R 2, which are two-axis measurement beams viewed from above, which are emitted from the interferometer 76Y.
IY ₂ has been irradiated. These measurement beams RI
Y ₁ and RIY ₂ irradiate the second reflection surface 60b vertically on the same horizontal plane at a predetermined distance in the X direction. These measurement beams RIY ₁ and RIY ₂ are emitted from a light source (not shown) and transmitted as linearly polarized light beams through the polarization beam splitters 62A and 62B, respectively.
It becomes circularly polarized light via 4B and irradiates the second reflection surface 60b. The returned light is transmitted through the λ / 4 plates 64A and 64B again, becomes a linearly polarized light beam orthogonal to the first polarization condition, is reflected by the polarization beam splitters 62A and 62B, respectively, and enters the corner cube parts 66A and 66B. Here, the light beams reflected on the three surfaces again pass through the polarization beam splitters 62A and 62B and the λ / 4 plates 64A and 64B, become circularly polarized light, and reach the second reflection surface 60b. Then, when the reflected light passes through the λ / 4 plates 64A and 64B, it becomes linearly polarized light having the same polarization condition as the first, passes through the polarization beam splitters 62A and 62B, and returns to the interferometer main body in parallel with the incident light flux. It has become. That is, the measurement by each of the measurement beams RIY ₁ and RIY ₂ is performed by a so-called double-pass configuration.

The returning light beam overlaps with the returning light beam of the reference beam from a fixed mirror (not shown) in the main body of the interferometer, and the interference fringes of the overlapping light beams are counted, whereby the accuracy of the substrate table TB is doubled. FIG. 3 of the second reflecting surface 60b of FIG.
(B), the positions on the axes Y ₁ and Y ₂ indicated by the dashed lines can be independently measured. Further, the rotation of the substrate table TB can be obtained based on the difference between the measurement values of the measurement beams RIY ₁ and RIY ₂ .

However, the ability to measure rotation only is not sufficient, especially in the case of a configuration in which the side surface of the substrate table is mirror-finished as a movable mirror as in this embodiment. In such a case, the measurement beam from the interferometer cannot be set at the same height as the wafer W surface. In consideration of such a point, as shown in FIG.
From Y, a third measurement beam RIY ₃ is irradiated from a position irradiated by the measurement beam RIY ₁ (or RIY ₂ ) at a predetermined distance in a plane direction (downward) perpendicular to the XY plane. I have. Therefore, the measurement beam RIY ₁ (or RIY ₁
It is possible to obtain the inclination with respect to the XY plane of the substrate table TB based on the difference ₂₎ and the measurement beam RIY _3.

In this sense, the measurement beam RIY
The third and fourth length measuring beams may be respectively radiated to positions separated by a predetermined distance in the plane direction (downward) perpendicular to the XY plane from the irradiation positions of ₁ and RIY ₂ respectively. . That is, at least three non-collinear measuring beams from the interferometer 76Y are output from the interferometer 76Y on the second reflecting surface 60b so that the rotation of the substrate table TB in the XY plane and the inclination with respect to the XY plane can be obtained. Second reflecting surface 60
It is desirable to adopt a configuration that irradiates b. In addition, it is needless to say that the measurement by the third and fourth measurement beams should also have a so-called double-pass configuration in order to improve the measurement accuracy.

Similarly to the above interferometer 76Y, the other interferometers 76X1 and 76X2 irradiate three measuring beams to the first reflecting surface 60a and the third reflecting surface 60c and receive the respective reflected lights. Thus, the positions of the irradiation points of the respective measurement beams on the first reflection surface 60a and the third reflection surface 60c in the respective measurement beam directions are independently measured. In FIG. 3A, the interferometers 76X1, 76X
Each of the three (or four) length measurement beams from 2, 76Y is typically interferometer beams RIX1, RIX2, RI
It is shown as Y.

In this case, as shown in FIG.
Reflecting surface 60 on each side of equilateral triangular wafer table TB
a, 60b, 60c, interferometers 76X1, 76Y, 76
X2 is an actuator ZACX for vertically irradiating an interferometer luminous flux composed of at least three length-measuring beams, and driving tilt and Z directions to opposing positions of each interferometer luminous flux.
1, ZACY, and ZACX2 are arranged, and the actuators ZACX1, ZACY, and ZACX2 can be independently controlled according to the tilt angles of the corresponding reflection surfaces measured by the respective interferometers, so that a high tilt drive control response can be obtained. Has become.

Referring back to FIG. 2, a spatial image detector KES for photoelectrically detecting an image of a test pattern or an alignment mark on the reticle R projected through the projection optical system PL is provided in a part of the substrate table TB. Fixed. The aerial image detector KES is mounted so that the surface thereof is substantially the same as the height position of the surface of the wafer W.
However, actually, when the substrate table TB is set at the center of the entire movement stroke (for example, 1 mm) in the Z direction, the image plane of the projection optical system PL and the surface of the aerial image detector KES coincide with each other. Have been.

The aerial image detector KES is used for measuring the amount of exposure, measuring the illuminance unevenness, measuring the imaging characteristics, and the like. Here, the configuration of the aerial image detector KES and the measurement of imaging characteristics using the same will be described in detail. FIG. 4 schematically shows a configuration of the aerial image detector KES mounted on the substrate table TB in FIG. 2 and a configuration of a signal processing system related thereto.

In FIG. 4, aerial image detector KES
Is a light-shielding plate 140 provided so as to have substantially the same height (for example, in the range of about ± 1 mm) as the surface of the wafer W on the substrate table TB, and several tens of μm formed at a predetermined position on the light-shielding plate 140. A rectangular aperture (knife-edge aperture) 141 having a diameter of about several hundred μm, an imaging light flux transmitted from the projection optical system PL through the aperture 141 and having a large NA (numerical aperture) are incident by a quartz light pipe 142 and a light pipe 142. A semiconductor light receiving element (silicon photodiode, PIN photodiode, or the like) 143 that photoelectrically detects the amount of an image forming light beam transmitted without loss is provided.

When the illumination light for exposure is obtained from the excimer laser light source 11 as in this embodiment, the photoelectric signal from the light receiving element 143 of the aerial image detector KES has a pulse waveform corresponding to the pulse emission of the excimer laser light source 11. Become. That is, assuming that an image optical path from a certain object point on a test reticle (not shown) installed on the object plane of the projection optical system PL is MLe, the image optical path MLe matches the rectangular aperture 141 of the aerial image detector KES. With the substrate table TB (ie, wafer stage WST) positioned in the X and Y directions,
When the excimer laser light source 11 in FIG. 2 emits pulses, the photoelectric signal from the light receiving element 143 also has a time width of 10 to 2.
It has a pulse waveform of about 0 ns.

In consideration of this, in the present embodiment, the photoelectric signal from the light receiving element 143 is input and amplified into the signal processing system of the aerial image detector KES, and the receiver 76E of the laser interferometer system 76 is described. 10nm made of
A sample-and-hold circuit (hereinafter, referred to as a sample-and-hold circuit) that alternately performs a sample operation and a hold operation in response to a counting pulse signal for each
An “S / H circuit” 150A is provided. In addition, the signal processing system includes an A / D converter 152A for converting the output of the S / H circuit 150A into a digital value, and a waveform memory circuit (RAM) 15 for storing the digital value.
3A and a computer 154 for waveform analysis. Also, in this case, 1 sent from the laser interferometer system 76 as an address counter of the RAM 153A.
An up-down counter 151 that counts a pulse signal for counting every 0 nm is provided.

In this embodiment, the excimer laser light source 11
The control computer 11B (see FIG. 2) is operated by the wafer stage controller 78 based on the measurement values from the laser interferometer system 76,
0, triggering pulse emission according to the coordinate position information sent to main controller 50. That is, in the present embodiment, the pulse emission of the excimer laser light source 11 is
The S / H circuit 150A holds the peak value of the pulse signal waveform from the light receiving element 143 in synchronization with the pulse emission. The peak value held by the S / H circuit 150A is converted into a digital value by an A / D converter 152A, and the digital value is stored in a waveform memory circuit (RAM) 153.
A is stored. The address (address) at the time of the storage operation of the RAM 153A is generated by the up / down counter 151, and the position of the substrate table TB and the RAM 153A are stored.
Is uniquely associated with the address at the time of the storage operation.

By the way, the peak intensity of the pulse light from the excimer laser light source 11 fluctuates by about several% for each pulse. Therefore, in order to prevent the image measurement accuracy from deteriorating due to the fluctuation, as shown in FIG. 4, the signal for the intensity detection provided in the illumination optical system is provided in the signal processing circuit of the present embodiment. S / H circuit 1 to which a photoelectric signal (pulse waveform) from detector (integrator sensor) 46 is input
50B (which has the same function as the SH circuit 150A), an A / D converter 152B for converting the output of the S / H circuit 150B into a digital value, and a waveform memory circuit (RAM) for storing the digital value 153B (the address generation during the storage operation is common to the RAM 153A).

Thus, the position of the substrate table TB and R
The peak intensity of each pulse light from the excimer laser light source 11 is stored in the RAM 153B in a state where the address (address) at the time of the storage operation of the AM 153B is uniquely associated.

As described above, each of the RAMs 153A, 153A
The digital waveform stored in 3B is read into a waveform analysis computer (CPU) 154, and a measurement waveform corresponding to the image intensity stored in RAM 153A is normalized by the intensity fluctuation waveform of the illumination pulse light stored in RAM 153B ( Division). The standardized measurement waveform is temporarily stored in a memory in the waveform analysis computer 154, and the center position of the image intensity to be measured is obtained by various waveform processing programs.

In this embodiment, the test pattern image on the test reticle is detected using the edge of the opening 141 of the aerial image detector KES.
4 is the coordinates of the substrate table TB (wafer stage 14) measured by the laser interferometer system 76 when the center of the test pattern image coincides with the edge of the opening 141 in the XY plane. Determined as position.

The information on the center position of the test pattern image analyzed in this way is sent to main controller 50, where main controller 5
Reference numeral 0 denotes an operation for sequentially measuring the position of each projected image of a test pattern formed at a plurality of points (eg, ideal lattice points) on the test reticle. The computer 11B for controlling the excimer laser light source 11, the wafer stage controller 78,
And instruct the computer 154 for waveform analysis.

As described above, the imaging performance of the projection optical system PL and the illumination characteristics of the illumination optical system are measured by the aerial image detector KES, and various optical elements shown in FIG. And mechanism can be adjusted.

Further, on the substrate table TB of the present embodiment, there is provided a reference mark plate FM whose surface is substantially the same as the height position of the surface of the wafer W (FIG. 5A )reference). On the surface of the fiducial mark plate FM, fiducial marks that can be detected by various alignment systems described later are formed, and these fiducial marks are used to check (calibrate) the detection center point of each alignment system.
It is used for measuring the baseline length between the detection center points, checking the position of the reticle R with respect to the wafer coordinate system, or checking the position in the Z direction of the best imaging plane conjugate to the pattern surface of the reticle R. If the reference marks are formed on the surface of the above-described KES, calibration in the X, Y, and Z tilt directions can be performed using the same reference plate, so that the accumulated error corresponding to each reference plate can be reduced. it can.

The wafer transfer robot 19 shown in FIG.
Is a part of a wafer transfer system that transfers a wafer W from a wafer mounting portion (not shown) to a wafer stage WST. Wafer W between
Arm (wafer load / unload arm) 21 for transferring the robot.

In the scanning type exposure apparatus 10 of this embodiment, as an alignment system, an alignment mark formed for each shot area on the wafer W without passing through the projection optical system PL, or a reference mark on the reference mark plate FM. An off-axis alignment sensor (alignment optical system) that optically detects the light is used. This alignment optical system ALG is arranged on the side of the projection optical system PL, as shown in FIG. The alignment optical system irradiates the resist layer on the wafer W with non-photosensitive illumination light (uniform illumination or spot illumination) through an objective lens, and reflects reflected light from an alignment mark or a reference mark through the objective lens. To detect photoelectrically. The mark detection signal photoelectrically detected is input to a signal processing circuit 68, which includes a wafer stage controller 78,
The measurement value of the laser interferometer system 76 is input via the synchronous control system 80 and the main controller 50. Then, the signal processing circuit 68 performs waveform processing on the above-described photoelectrically detected mark detection signal under a predetermined algorithm, and based on the processing result and the measurement value of the laser interferometer system 76,
Wafer stage W such that the center of the mark coincides with the detection center (index mark, reference pixel on image pickup surface, light receiving slit, spot light, etc.) in alignment optical system ALG.
The position shift amount of the wafer mark and the reference mark with respect to the ST coordinate position (shot alignment position) or the detection center is obtained. Information on the obtained alignment position or positional deviation amount is sent to main controller 50, and is used for positioning at the time of alignment of wafer stage WST, setting of a scanning exposure start position for each shot area on wafer W, and the like. .

Further, the scanning exposure apparatus 10 of the present embodiment
Then, reticle stage RST and wafer stage WST
And a synchronous control system 80 for synchronously moving the control signal and the control signal are provided in the control system. The synchronization control system 80 is used to control the reticle stage RST and the wafer stage WS, especially during scanning exposure.
When synchronizing the movement of T with the reticle stage controller 33, the control of the drive system 29 by the reticle stage controller 33 and the control of the drive system 48 by the wafer stage controller 78 are interlocked with each other. The positions and speeds of the reticle R and the wafer W to be measured are monitored in real time, and managed so that their mutual relationship becomes a predetermined one. The synchronous control system 80 is controlled by various commands and parameters from the main controller 50.

Further, the scanning exposure apparatus 10 of the present embodiment
Although illustration is omitted in FIGS. 1 and 2, actually,
During scanning exposure, the reticle stage RST having the mass Rm acts on the reticle base platen 28 from the reticle stage RST having the mass Rm in accordance with the acceleration / deceleration Ar generated during prescanning before and after the constant speed movement of the reticle stage RST during overscanning. In order to prevent force-Ar × Rm from being transmitted to the gantry 16 via the leg 26, the reaction actuator 7
4 are provided.

The reaction actuator 74
As shown in FIG. 6, a base plate B supporting the gantry 16
S is supported by a reaction frame 72 roughly positioned by an elastic body 70 with respect to S, and is disposed at substantially the same height as the center of gravity determined by the weight of the reticle stage RST, the reticle base surface plate 28, and the like.

In practice, a pair of left and right reaction actuators 74L and 74R are provided as the reaction actuator 74, but these are representatively shown as the reaction actuator 74 in FIG. The reaction actuator 74 is controlled by a control device (not shown) so as to apply a force opposite to the reaction force to the reticle base platen 28 so as to cancel the lateral shift and rotation of the center of gravity when the reticle stage RST is accelerated or decelerated. As a result, vibration during reticle acceleration / deceleration is not transmitted to the gantry 16 via the leg 26.

It can be said that such a reaction actuator has a higher necessity and effect when a linear motor or a two-dimensional magnetic levitation linear actuator is used than when a reticle stage of a feed screw system is used.

Next, the configuration of the control rack shown in FIG. 1 will be described.

The control rack 14 includes the excimer laser light source 1
1 and each unit of the exposure apparatus main body 12 (the illumination optical system 1).
8, reticle stage RST, wafer stage WST,
A processor board rack unit 104 for storing a plurality of processor boards for controlling each unit including the excimer laser light source 11, each processor board being constructed as a distributed system for individually controlling each of the transfer robots 19 and the like. That houses a main controller (minicomputer) 50 (see FIG. 2) that controls the entire system, an operation panel 106 for man-machine interface with an operator, and a rack that houses a display 108, etc. And a single rack configuration. The excimer laser light source 1 is controlled by the control rack 14.
1 and the overall operation of the exposure apparatus body 12 are managed.

Each processor board in the processor board rack section 104 is provided with a unit computer such as a microprocessor. A series of exposure processing of the wafer is executed.

The overall sequence of the series of exposure processing is totally controlled according to a predetermined process program stored in a memory (not shown) in main controller 50.

The process program is based on the exposure processing file name created by the operator, information on the wafer to be exposed (number of processed wafers, shot size, shot array data, alignment mark arrangement data, alignment conditions, etc.), and the reticle to be used. Information (pattern type data, arrangement data of each mark, size of circuit pattern area, etc.) and information on exposure conditions (exposure amount, focus offset amount, scanning speed offset amount, projection magnification offset amount, various aberrations and images The distortion correction amount, the setting of the σ value of the illumination system and the illumination light NA, the setting of the NA value of the projection optical system, etc.) are stored as a package of parameter groups.

Main controller 50 decodes the process program instructed to be executed, and instructs the operation of each component necessary for wafer exposure processing to the corresponding unit-side computer as a command one after another. At this time, when each unit computer completes one command normally,
The status to that effect is sent to the main controller 50, and the main controller 50 receiving the status sends the next command to the unit-side computer.

In such a series of operations, for example,
When a wafer exchange command is sent from main controller 50, wafer stage controller 78, which is a control unit for wafer stage WST, and wafer transfer robot 19
The wafer stage WST and the arm 21 (wafer W) are set in a positional relationship as shown in FIG.

Further, a plurality of utility software are stored in a memory in main controller 50. The representative software automatically measures the optical characteristics of the projection optical system and illumination optical system and evaluates the quality of the projected image (distortion characteristics, ascoma characteristics, telecentric characteristics, illumination numerical aperture characteristics, etc.) Measurement program for
There are two types of correction programs for performing various correction processes according to the quality of the evaluated projected image.

Next, the role of the movable platen 38 and its control method will be described with reference to FIGS. FIG. 5A shows a schematic plan view of the vicinity of the surface plate 22, and FIG. 5B shows a schematic front view seen from the direction of arrow A in FIG. 5A. In FIG. 5A, arrow C indicates the moving distance of movable surface plate 38 due to the reaction force on movable surface plate 38 due to acceleration / deceleration when wafer stage WST moves by the distance indicated by arrow B. .

A plurality of coils (not shown) constituting a planar magnetic levitation linear actuator 42 together with a permanent magnet (not shown) provided on the lower surface (bottom surface) of the wafer stage WST are provided on the upper surface of the movable platen 38 in XY2. It is stretched in the dimension direction. And, the wafer stage WST is
In addition to being levitated above the movable platen 38 by the planar magnetic levitation linear actuator 42, the coil is controlled in an arbitrary two-dimensional direction by controlling the current flowing through the coil.

Similarly, a plurality of coils (not shown) constituting the planar magnetic levitation linear actuator 44 together with a permanent magnet (not shown) provided on the lower surface (bottom surface) of the movable surface plate 38 are provided on the upper surface of the surface plate 22. ) Are stretched in the XY two-dimensional directions. The movable surface plate 38 is levitated above the surface plate 22 by the planar magnetic levitation linear actuator 44, and is driven in an arbitrary two-dimensional direction by controlling the current flowing through the coil. Configuration.

In this case, since the wafer stage WST and the movable surface plate 38 and the movable surface plate 38 and the surface plate 22 are not in contact with each other, the friction therebetween is extremely small. The momentum conservation law is established for the whole system including the WST and the movable surface plate 38.

Therefore, when the mass of wafer stage WST is m and the mass of movable platen 38 is M, wafer stage WST
When the ST moves at a speed v with respect to the movable platen 38, the movable platen 38 moves in the opposite direction to V =
It moves with respect to the surface plate 12 at a speed of mv / (M + m). However, since the acceleration is the time derivative of the velocity, when the wafer stage WST moves at the acceleration a (when the force F = ma is applied), the movable platen 38 applies the force F
, An acceleration of A = ma / (M + m) is received in the opposite direction.

In this case, since wafer stage WST is mounted on movable platen 38, wafer stage WST
Moves at a speed of v × (1-m / (M + m)) with respect to the surface plate 22, and therefore, at an acceleration of a × (1-m / (M + m)). Therefore, if the mass m (weight mg) of the wafer stage WST is close to the mass M (weight Mg) of the movable platen 38, it is not possible to obtain the desired acceleration and maximum speed of the wafer stage WST. Also, since the travel distance is proportional to the speed,
The moving amount of the movable platen 38 increases, and the footprint deteriorates.

For example, assuming that m: M = 1: 4, if it is desired to move the 300 mm wafer stage WST for the entire 12-inch wafer exposure, the above equation V = mv / (M + m)
Therefore, it is necessary to secure a stroke of the movable platen 38 for 60 mm, which is 1/5 of 300 mm.

Therefore, in this embodiment, the ratio of the mass m of the wafer stage WST to the mass M of the movable platen 38 is m: M in order to suppress the deterioration of the wafer stage acceleration, the maximum speed, and the footprint to one digit or less. = 1: 9 or less, that is, the weight of the wafer stage WST is set to be 1/9 or less of the weight of the movable platen 38.

In order to reduce the required stroke of the movable platen 38, the wafer stage controller 78 determines the control response to the planar magnetic levitation linear actuator 44 for driving the movable platen 38 during exposure, alignment, and the like. It is made to be variable at the time of.

This will be described in more detail. At the time of exposure, the wafer stage WST and the reticle stage RST move synchronously. However, if the control response of the planar magnetic levitation linear actuator 44 for driving the movable platen 38 is controlled at several Hz, it will be several tens of Hz. Can hardly follow the reaction force of the planar magnetic levitation linear actuator 42 for driving the wafer stage WST controlled by the movable surface plate 38, and the movable surface plate 38 moves freely according to the law of conservation of momentum. The force is absorbed, and the effect of the reaction does not reach the outside.

In wafer stage controller 78, position of reticle stage RST and wafer stage W
When the exposure apparatus main body 12 is tilted as a whole due to the change in the position of ST, the control response of the planar magnetic levitation linear actuator 44 is controlled at several Hz, so that the movable platen 38 moves in the tilt direction. The moving low-frequency position shift is prevented.

Even if m: M = 1: 9, if the wafer stage WST moves 300 mm full, the movable platen 38 also moves in the opposite direction by about 30 mm. Stepping length is at most 30
mm, so the movable platen 38 moves 3m at that time.
m. Therefore, in the present embodiment, the wafer stage controller 78 operates the planar magnetic levitation type for driving the movable platen 38 during deceleration of the wafer stage (at the time of non-scanning stepping acceleration) which does not affect the synchronization control performance after scan exposure. The response frequency in the same direction as the stepping of the linear actuator 44 is increased to several tens Hz, and the movable surface plate 38 is increased.
The linear encoder 45 (FIG. 5) as a position measuring device for detecting the position of the relative movement of the
(B), the movable platen 38 is controlled to return to the original position before stepping. Thereby, the movable platen 38
5A can be reduced (see the phantom line 38 'in FIG. 5A). In addition, since the movable platen 38 and the platen 22 can be considered to be in a fixed state, the wafer acceleration, The maximum speed can also be improved by 10%.

Such a control method can be similarly applied to the movement of wafer stage WST between other alignments and the movement to the loading position when exchanging wafers.

The vibration isolator 20 supporting the gantry 16
Has an air pad for preventing high-frequency vibration such as floor vibration and a linear actuator for removing low-frequency vibration accompanying the air pad.
The apparatus may slightly tilt depending on the position of wafer stage WST. In this case, it is necessary to correct the inclination by continuously applying a predetermined voltage to the linear actuator constituting the vibration isolator 20. However, since the load is always applied to the actuator, the life of the actuator and other components is shortened. In such a case, in this embodiment, the wafer stage controller 78 moves the movable platen 38 by a predetermined amount as described above, thereby forcing the center of gravity of the entire apparatus.
The inclination of the device can be corrected so that no load is applied to the linear actuator, and the life of components such as the actuator can be extended.

In the present embodiment, with the various measures described above, the shape of the movable platen 38 and its moving range are changed according to the shape and the moving range of the wafer stage WST in FIG.
(A) It has a triangular shape without vertices as shown by a solid line and a virtual line in FIG. In this case, the wafer stage W
The scanning direction of ST (scanning direction) is the vertical direction of the drawing in FIG. In the present embodiment, the surface plate 22 is formed in a substantially square shape, and the four vibration isolating devices 20 supporting the surface plate are arranged in a quadrangular shape in order to increase rigidity. May be formed in a shape similar to that shown by a virtual line 38 'in FIG. 5A, and the vibration isolator 20 may be arranged in a three-point arrangement as shown by a dotted line 20' in FIG. 5A. . This can obviously improve the footprint. However, in this case, it is necessary to increase the rigidity of the vibration isolator.

Next, one shot performed by a stage control system (wafer stage controller 78, reticle stage controller 33, synchronization control system 80) for relatively moving reticle stage RST and wafer stage WST in the scanning direction (Y direction). The basic scanning procedure of the wafer stage when exposing an area will be briefly described with reference to FIG.

FIG. 7A shows a slit-shaped illumination area on the wafer (an area conjugate to the illumination area on reticle R; hereinafter, referred to as an effective area PL ′ of projection optical system PL).
FIG. 7 is a plan view showing the relationship between ST (referred to as “illumination slit”) ST and shot area S1 as one partitioned area.
(B) shows the relationship between the stage movement time and the stage speed. Actually, the exposure is performed by moving the shot area S1 in the direction opposite to the arrow Y with respect to the illumination slit ST, but here, the table of FIG. It is shown that the on-wafer illumination slit ST moves with respect to the shot area S1 in order to correspond to

First, as a basic (general) scanning procedure, the center P of the illumination slit ST is positioned at a predetermined distance from the shot end of the shot area S1, and acceleration of the wafer stage WST is started. Wafer stage W
When ST approaches a predetermined speed, synchronous control of reticle R and wafer W is started. Time t1 from the start of the acceleration of the wafer stage to the start of the synchronous control is represented by
Called acceleration time. After the start of the synchronous control, the reticle stage RS
The tracking control by T is performed, and the exposure is started. The time t2 from the start of the synchronous control to the start of the exposure is called a settling time.

The time (t1 + t2) from the start of the acceleration to the start of the exposure is called a prescan time. Assuming that the average acceleration at the acceleration time t1 is a and the settling time is t2,
The moving distance during prescan is (1/2) · at
It is represented by 1 ² + a · t1 · t2.

The exposure time t3 during which exposure is performed by constant-speed movement is t3 = (L + w) / (at) where the shot length is L and the width of the illumination slit ST in the scanning direction is w.
1), and the moving distance is L + w.

The transfer of the reticle pattern to the shot area S1 is completed at the end of the time t3. However, in order to improve the throughput, in the step-and-scan method, the normal reticle R is alternately scanned (reciprocally scanned), thereby sequentially. Since the exposure for the next shot is performed, the reticle R is further moved from the end of the exposure by the same distance as the movement distance in the prescan, and
Is returned to the scanning start position for the next shot exposure (therefore, the wafer W is also moved in the scanning direction correspondingly).
It is necessary. The time for this is the constant speed overscan time t4 and the deceleration overscan time t5, and (t4 + t5) is the overscan time as a whole. If the deceleration at the deceleration overscan time t5 is b, the moving distance in this overscan time is-(1/2) .b.t5 ² -b.t5.t4, and this distance is (1/2). a · t1 ² + a · t1 · t
T4 and t5 and the deceleration b are set so as to be 2.

Since a = -b in a general control system, t1 =
It is the easiest control method to set t5 and t2 = t4. As described above, in the scan exposure, a prescan distance and an overscan distance are required in order to perform a constant-speed synchronous scan, and even when exposing a wafer peripheral shot, the interferometer light flux is interposed between the prescan and the overscan. Must not deviate from the reflecting surface (moving mirror). Therefore, it is necessary to make the reflecting surface longer accordingly.

Next, the setting of the length of each reflection surface of the substrate table TB in this embodiment will be described with reference to FIG. FIG. 7 (C) shows a wafer peripheral shot S when the wafer stage WST (substrate table TB) scans in the arrow Y direction to expose a shot area S around the wafer, and a moving mirror length extension (L0, L1 + L2). , L
3) is shown. In FIG. 7C, the length of the reflecting surfaces 60a and 60c when the extension line of the interferometer beams RIX1 and RIX2 intersects the outer periphery of the wafer W is the minimum necessary length of the reflecting surface. When the shot S can be exposed in a state where the shot S is chipped on the outer periphery of the wafer W, the missing virtual shot length is L3, the distance required for the pre-scan and the overscan described above is L1 + L2, and the interferometer beam is 2 in the XY plane. The total sum of the center position (dotted line portion) of the two measurement beams, the distance to the center of each measurement beam, the beam radius, and a predetermined margin when the two measurement beams are used is L
Assuming 0, the extension of the reflecting surface is L0 + L1 + L2 + L3
The length of the reflecting surface is set such that the value is smaller than the vertex of the triangle of the substrate table TB.
This prevents an inconvenience that the measurement beam deviates from the reflecting surface during the scanning exposure. However, since it is not necessary to completely expose the shot on the outer periphery of the wafer by the shot length L, the extension of the movable mirror is controlled to be L0 + L1 + L2 by controlling only the portion exposed on the wafer.
It is good.

The basic scanning procedure of the wafer stage at the time of exposing one shot area is as described above. However, when the reticle pattern is sequentially transferred to a plurality of adjacent shot areas, wafer stage WST ( The method of controlling the movement of the substrate table TB) is the greatest feature of the present invention, and will be described in detail below. Here, as an example, adjacent shots S1 and S1 shown in FIG.
A case where S2 and S3 are sequentially exposed will be described.

FIG. 8A shows shots S1, S2, and S3.
3 shows a trajectory in which the center P of the on-wafer illumination slit ST passes over each shot in the case of sequentially exposing.
As is clear from FIG. 8A, the wafer stage controller 78 and the synchronization control system 80 perform pre-scanning and over-scanning of the wafer stage WST in the scanning direction (Y direction) and in the non-scanning direction (X direction). Of the wafer stage WST is performed at the same timing. Thereby, the moving distance between shots of wafer stage WST is shortened, so that the moving time required for this is shortened, and the throughput is improved.

As described above, since the pre-scan time includes the settling time t2 for causing the reticle R to completely follow the wafer W, the acceleration / deceleration control in the non-scan direction is performed as much as possible from the start of the settling time t2. It is desirable to finish early. To achieve this, in the present embodiment, the wafer stage controller 78 and the synchronization control system 80 use the wafer stage WS following the end of the exposure.
The stepping of the wafer stage WST in the non-scanning direction is started during the constant-speed overscan time t4 in the scanning direction of T. Control to end the deceleration control is performed. In FIG. 8B,
In this case, a relationship between speed Vy in the scanning direction of wafer stage WST and time is shown, and FIG. 8C shows a corresponding relationship between speed Vx in the non-scanning direction and time. According to this method of controlling the movement of the wafer stage, during the settling time t2, only the synchronous control in the scanning direction can be concentrated, so that the settling time t2 (and therefore t4) can be shortened.

Here, when the stepping direction is the X axis, the scan direction is the Y axis, the scan speed at the time of exposure of the shot S1 is -VY, and the maximum speed at the time of stepping is VX, the time distribution is specifically described for each axis. To think.

First, considering the scanning direction, the exposure of the shot S1 is completed and the uniform overscan time t4
Later, wafer stage WST decelerates (− in FIG. 8A).
(Acceleration in the + Y direction when having a speed in the Y direction). Assuming that the deceleration at this time is ay, wafer stage WST is set using point O (0, 0) in FIG.
Advances in the scanning direction by −VY · t4 during the time t4, and thereafter changes to −VY · t + (）) · ay · t ² with the time point after the lapse of the time t4 as a time reference point. And −VY · t + (１ ／) · ay · t ² = −VY
· Time point when t · (１ ／) is satisfied, that is, t = t _y 5
At the time when = VY / ay (see FIG. 8B), a branch point B (see FIG. 8A) at which the prescan for the shot S2 as another partitioned area is started. Thereafter, during the acceleration period, the acceleration start point is set to 1 / 2.ay with respect to time.
· T take ² locus, it continues to accelerate until t _y 1 = VY / ay, then, through t2 as synchronous control period of the reticle R and the wafer W, the exposure is started. Exposure time t
3 is t3 = (shot length Ly + illumination slit width w) / V
It is represented by Y. At this time, the trajectory of wafer stage WST is parabolic. The actual parabola is y = x ² Or y
= √x, but here, if t is deleted, x ²
And √x, and for convenience, a parabolic shape indicates a function including these functions.

Next, considering the stepping direction, wafer stage WST starts accelerating immediately after exposure of shot S1 is completed. When the acceleration and ax, wafer stage X coordinate 8 as a reference point O (0,0) point in (A) (1/2) · ax · t 2 next WST, t = t _x 5
= VX / ax (see FIG. 8C), the maximum speed is reached. Here, the stepping length Lx ≦ ax · t _x 5 ² Case of, t _x 5 = deceleration from the time of √ (Lx / ax) (+ X
(Acceleration in the -X direction when having speed in the direction).
Thereafter, during the deceleration period, the deceleration start point is used as a time reference point, and a
x · t _x 5 · t- (1/2) · ax · t ² It changes _{as, ax · t x 5 · t-} (1/2) · ax · t 2 = (1
_{/ 2) · ax · t x} 5 · t become time, that is, reduced to the point of elapse of t _x 5 from the deceleration start point time stops.

That is, as shown in FIG. 8B, the scanning direction is from the end of exposure of the previous shot to t4 +
t _y 5 + in t _y 1 + t2 but starts exposure of the next shot, as the stepping direction as shown in FIG. 7 (C), tx5 + t4 + tx from the exposure end time of the previous shot
Acceleration / deceleration has been completed at time point 1, and from this, t _y 1
= T _x 1, t _y 5 = t _x 5, t 2 as described above
= T4, it can be seen that the stepping operation ends earlier than the start of the synchronization control at the settling time t2 in the scanning direction by t4.

In other words, the point at which the speed in the scanning direction becomes zero, that is, the point at which deceleration ends and acceleration for the exposure of the next shot is started, is shown in FIG.
The X coordinate Bx of the point B (Bx, By) in FIG.
The wafer stage controller 78 and the synchronous control are performed such that the stepping operation in the non-scanning direction is performed in parallel with the overscanning and prescanning operations in the scanning direction of the wafer stage WST so as to be closer to S2 from the boundary between 1 and S2. This means that the system 80 controls the movement of the wafer stage WST in the X and Y directions.

In the description so far, the acceleration at the time of stepping is ± ax. However, if the acceleration at the time of deceleration is -bx with respect to the acceleration at the time of acceleration and | -bx | <ax, As compared with the case where the magnitude of the acceleration is the same during acceleration and deceleration, although the stepping time is longer, the magnitude of the acceleration itself during deceleration becomes smaller, so the apparatus including the wafer stage WST accompanying the deceleration is used. There is an effect that the vibration itself can be reduced. Therefore, the settling time at the time when the stepping in the non-scanning direction ends is shortened.

In the above description, the stepping length L
Having described the case of ^{_{x ≦ ax · t x 5 2}} , Lx> ax ·
For _{^{t x 5 2, t x 6}} = (Lx-ax · t x 5 2) /
It is sufficient to control the position of wafer stage WST in the X direction so as to start the deceleration operation after scanning at maximum speed VX for time tx6 that satisfies VX. However, in any _{t4 + t y 5 + t y} 1 ≧ t x 5 + t x 6 + tx1 become as acceleration ax, to set the maximum speed VX is important. By doing so, all the stepping times are performed in parallel with the prescan and overscan, and the throughput is improved.

That is, wafer stage WST (substrate table T) described with reference to FIGS.
According to the scanning exposure method employing the movement control method of B),
The reticle R and the wafer W are scanned in the Y direction (first scanning direction).
After the shot S1 is scanned and exposed, before the wafer W reaches the position of the shot S2 adjacent to the shot S1 in the X direction (non-scanning direction) (in the non-scanning direction between shots). The acceleration of the wafer W in the scanning direction is started (during deceleration before the stepping is completed), and the shot S2 is scanned and exposed using the pattern of the reticle R. In other words, the movement to the shot S2 is started after the exposure of the shot S1 is completed, but the acceleration of the wafer in the scanning direction is started during this movement.
In the non-scanning direction movement time, the scanning direction acceleration time for exposure of the shot S2 can be at least partially overlapped, and the exposure time of the shot S2 after the wafer W reaches the position of the shot S2 It is clear that the throughput can be improved as compared with the conventional example in which the acceleration in the scanning direction is started.

In the case of FIG. 8, the acceleration of the wafer W in the non-scanning direction is started at the time of the uniform movement in the scanning direction after the end of the scanning exposure of the shot S1, but this is settling in the scanning direction. This is intended to end the stepping operation by the time t4 earlier than the start of the synchronous control at the time t2, and is not limited to this, and the acceleration of the wafer W in the non-scanning direction is started during the deceleration of the wafer W. You may do it.

In this case, the wafer W is accelerated in a direction intersecting the scanning direction before the scanning exposure of the shot S2, and the moving speed in the scanning direction is set to a speed corresponding to the sensitivity characteristic of the wafer W. Therefore, during exposure, the speed can be maintained and the reticle can be synchronously controlled, so that the control is easy.

As is clear from FIGS. 8B and 8C, the wafer W is moved between the scanning exposure of the shot S1 and the scanning exposure of the shot S2 in the scanning direction and the non-scanning direction. Is moved so that at least one of the moving speeds does not become zero. Therefore, the moving is performed without stopping between the scanning exposure of the shot S1 and the scanning exposure of the shot S2, thereby improving the throughput.

As is apparent from FIG. 8A, the wafer W is moved between the scanning exposure of the shot S1 and the scanning exposure of the shot S2 in the X direction at the point B where the moving speed in the scanning direction becomes zero. Is moved so as to be closer to the shot S2 than to the shot S1, so that the acceleration in the non-scanning direction of the wafer W between the shot S1 and the shot S2 is equal to the deceleration as described above. However, even if there is a certain time before the start of the exposure of the shot S2, a certain time (t
2) Before, the speed in the non-scanning direction is zero. Therefore, it is not necessary to increase the deceleration of the wafer W after the acceleration in the non-scanning direction between the scanning exposure of the shot S1 and the scanning exposure of the shot S2. Is not unnecessarily long.

However, the wafer W is not necessarily moved between the scanning exposure of the shot S1 and the scanning exposure of the shot S2 in FIG.
It is not necessary to move the wafer W along the movement trajectory shown in FIG.
In order to scan and expose the shot S2, the position of the wafer in the non-scanning direction (the position of the point B in the X direction) at which the speed component in the scanning direction becomes zero is set to be closer to the shot S1 than the position of the shot S2 in the X direction. Alternatively, the wafer W may be moved obliquely with respect to the scanning direction and the non-scanning direction. Or shot S
Between the scanning exposure of No. 1 and the scanning exposure of shot S2, the position in the non-scanning direction of the wafer W where the speed component in the scanning direction after the scanning exposure of the shot S1 is zero (the position of the point B in the X direction).
However, the wafer W may be moved between the position of the shot S1 in the non-scanning direction and the position of the shot S2 in the non-scanning direction. In these cases, when the scanning exposure of the shot S1 is completed, the wafer W is moved in the non-scanning direction while reducing the speed in the scanning direction, and the wafer W moves along a curved (or straight) path. It is moved obliquely with respect to the scanning direction and the non-scanning direction. Accordingly, the movement trajectory of the wafer W after the scanning exposure of the shot S1 is completed is shorter than that of the conventional U-shaped path, and the wafer W is moved along a path that is closer to the shortest distance, thereby improving the throughput. In this case,
Although the movement trajectory of the wafer W may be V-shaped, the wafer W is moved without stopping between the scanning exposure of the shot S1 and the scanning exposure of the shot S2, and the trajectory is parabolic (or U-shaped). Character).

Also, as is clear from FIGS. 8A and 8C, after the scanning exposure of the shot S1, the wafer W is accelerated in a direction intersecting the scanning direction and the non-scanning direction, and thereafter, for a predetermined time. (T2 + α) Since exposure is started after moving at a constant speed in the scanning direction, the speed component of the wafer W in the non-scanning direction does not affect the scanning exposure after the start of exposure.

In this case, during movement of the wafer W in a direction intersecting the scanning direction and the non-scanning direction, and before the velocity component of the wafer W in the non-scanning direction becomes zero, the reticle R
Is accelerated, the time required for the reticle R and the wafer W to be in a constant-speed synchronization state is reduced as compared with the case where the acceleration of the reticle R is started after the wafer moves to the constant speed movement, The throughput can be improved accordingly. Note that the acceleration and deceleration (negative acceleration) refer to average acceleration / deceleration during operation, and the same effect as in the present embodiment can be obtained in acceleration / deceleration map control for smooth acceleration / deceleration. Needless to say.

Next, referring to FIG. 9, first to third interferometers 76X1, 76Y, and 7Y constituting the interferometer system of FIG.
The arrangement of the 6 × 2 measurement beam in the apparatus, the method of calculating the X and Y positions and rotation of the substrate table TB by the wafer stage controller 78, and the like will be described in detail. FIG. 9 is a plan view near the movable platen 38 where the wafer stage WST is located at the loading position for exchanging the wafer W.

As shown in FIG. 9, interferometers 76X1, 76Y, 76X2 for monitoring the position of wafer stage WST on the XY coordinate system (stage coordinate system).
Has two length measuring beams in plan view, and each of these two length measuring beams is used as three independent light beams for yawing measurement as three reflecting surfaces 60a, 60b, and 60c of the substrate table TB. (Note that the interference measurement long beam for tilt direction measurement is not shown).

One of the measurement beams (the first measurement axis R) emitted from the first and third interferometers 76X1 and 76X2, respectively.
IX11, the projection optical system PL is located at a position where an extension of the measurement beam of the third measurement axis RIX21) and an extension of the center line of the two measurement beams emitted from the second interferometer 76Y intersect.
Are located, and the interferometers 76X1 and 76X
2 is a position where the extension lines of the remaining measurement beams (the measurement beams of the second measurement axis RIX12 and the fourth measurement axis RIX22) emitted from the second interferometer intersect each other, and are emitted from the second interferometer 76Y. The detection center of the alignment optical system ALG is located at a position where the extension lines of the center lines of the two measurement beams intersect.

In this case, wafer stage controller 7
In step 8, the average value (y1 + y2) / 2 of the measured values y1 and y2 of the positions in the Y-axis direction by the two measurement beams emitted from the interferometer 76Y is always calculated as the Y position of the substrate table TB. That is, the substantial measurement axis of the interferometer 76Y is the optical axis of the projection optical system PL and the alignment optical system AL.
The Y axis passes through the G detection center. The two measurement beams emitted from the interferometer 76Y do not come off the second reflection surface 60b of the substrate table TB in any case. The rotation (yaw) of the substrate table TB can be obtained by using any two measured values of the interferometers 76X1, 76X2, and 76Y. However, as described later, the interferometer 76X is used at the time of alignment.
Since there is a possibility that one of the 1,76X2 length measuring beams may deviate from the reflection surface of the substrate table, the wafer stage controller 78 also rotates the substrate table TB with the interferometer 76Y.
The calculation is performed based on the difference between y1 and y2 of the measured values of the position in the Y-axis direction by the two length measurement beams emitted from. When the rotation can be obtained based on the measured values of the interferometers 76X1, 76X2, and 76Y, the wafer stage controller 78 sets any one of the obtained rotation amounts, or any two or three of the rotation amounts. The rotation may be obtained by two averaging.

Also, in the present embodiment, the first interferometer 76
X1 irradiates the first interferometer beam RIX1 in a direction inclined at a predetermined angle θ1 (θ1 is −60 ° here) with respect to the Y-axis direction perpendicularly to the first reflection surface 60a, and the third interferometer 76X2
Is a predetermined angle θ2 with respect to the Y-axis direction (θ2 is +
(60 °) The interferometer beam RIX2 in the inclined direction is irradiated perpendicularly to the third reflecting surface 60c.

Therefore, the measured value based on the reflected light of the interferometer beam RIX1 is represented by X1, the interferometer beam RIX
Assuming that the measurement value measured based on 2 is X2, the X coordinate position of wafer stage WST can be obtained by the following equation (1). X = {(X1 / sin θ1) − (X2 / sin θ2)} × (1/2) (1)

In this case, the interferometer beams RIX1 and RIX
2 is a direction symmetric with respect to the Y axis,
Since inθ1 = sinθ2 = sinθ, the X coordinate position of wafer stage WST can be obtained from X = (X1−X2) / (2sinθ) (1 ′).

However, since it is important to prevent a so-called Abbe error from occurring, in the wafer stage controller 78, at the time of exposure, the first and second light beams emitted from the interferometers 76X1 and 76X2 toward the optical axis of the projection optical system PL are exposed. 1. The X position of the wafer stage WST is calculated by the above equation (1) ′ using the measurement value of the measurement beam on the third measurement axis, and the alignment center of the alignment optical system ALG is obtained from the interferometers 76X1 and 76X2 during alignment. The X position of the wafer stage WST is calculated by the above equation (1) ′ using the measurement values of the measurement beams of the second and fourth measurement axes respectively emitted toward the.

However, with respect to the scanning direction of wafer stage WST, the inclination of first and third reflecting surfaces 60a and 60c is set to be a predetermined angle (θ1 + 90 °) or (θ2-90 °). There is a need to. The inclination of the first and third reflecting surfaces 60a and 60c is adjusted in advance so as to be the same, and then θ1 and θ2 during reticle alignment using the reference mark plate FM on the wafer stage WST.
Is measured, and based on the difference, the X obtained by the above equation (1) or (1) ′ is corrected, whereby stable measurement of the stage position can be performed.

In the present embodiment, unlike the conventional two-way interferometer, each interferometer beam is located at a position rotated by 120 ° from each other. The two locations are hidden by the shadow of the wafer stage WST, making air conditioning difficult. Therefore, at least two of the three locations are provided with air outlets that independently perform air conditioning, and the configuration is such that a temperature-controlled gas can be sent to the three interferometer beams without stagnation. I have. This air blowing method includes a light beam parallel air conditioning method that blows air from the interferometer side to the stage, and a light beam orthogonal air conditioning method that blows the light beam from top to bottom. Thus, the air conditioning method may be selected independently for each axis.

Next, the operation from the wafer exchange to the end of the exposure in the scanning type exposure apparatus 10 of the present embodiment will be described with reference to FIGS.

At the wafer loading position shown in FIG. 9, all the measurement beams from all the interferometers of the interferometer system 76 are irradiated on the respective reflection surfaces of the substrate table TB. This includes a reticle alignment sensor (not shown) that uses exposure light that transmits different marks on the reference mark plate FM through the projection optical system PL at the same time as wafer replacement,
Since the reference mark plate FM is arranged at one end of the triangular apex of the substrate table TB so that it can be observed simultaneously with the alignment optical system (off-axis alignment sensor) ALG, at this time, the measurement beam is applied to each of the substrate tables TB. In such a way as not to deviate from the reflecting surface. Thereby, at the time of exposing the exposed wafer to be unloaded simultaneously with the wafer exchange, the reset operation of the interferometer for the alignment optical system ALG in which the measurement beam is deviated from the reflecting surface (moving mirror), the reticle alignment, and Baseline measurement can be performed. This reticle alignment and baseline measurement are described in
The quick alignment mode disclosed in JP-176468 is used. In FIG. 9, shots that can be exposed by one scan on the wafer W are written by solid lines, and square dashed lines indicate positions where the wafer stage WST must move in prescan and overscan. .

When the wafer exchange and the baseline measurement are completed, alignment is performed, for example, as described in JP-A-61-44.
No. 429, enhanced global
The sample alignment by the alignment (EGA) is executed. That is, wafer stage WST corresponds to FIG.
The alignment marks formed on at least three shots (eight shots in FIG. 10) on the wafer are detected by the alignment optical system ALG in the order according to the arrow (→) written on the wafer W of “0”. And the position of wafer stage WST at each mark detection position, ie, alignment optical system AL.
The positions of a plurality of representative marks are measured by using a measurement value of an interferometer in which a length measurement axis passes through a G detection center point (or an optical axis). The measurement order of the alignment marks in this case is determined as follows.

That is, since the end of the wafer exposure is the upper left shot close to the loading position, when a full alternate scan with the highest throughput is performed, the lower left shot is obtained when the total exposure shot row is an even row, and the lower left shot is obtained when the total exposure shot row is an odd row. The lower right shot is the exposure start point. Therefore, after the measurement on the reference mark plate FM, the alignment sequence starts with a shot close to that position and ends at a position close to the exposure start shot position. The wafer stage controller 78 decides.

When the EGA measurement according to the above measurement order is completed, the length axis of the interferometer used for measuring the position of wafer stage WST by wafer stage controller 78 is changed to the optical axis of the exposure interferometer (first and third length measurement axes). Axis), the step / step for a plurality of shot areas on the wafer W is performed.
Exposure of the AND scan method is started. in this case,
As shown in FIG. 11, since the total exposure rows are even rows,
Exposure is started from the lower left, and scan exposure is performed sequentially and alternately. When the first line is exposed in the order of left to right, the next line is alternately stepped from right to left, and finally when the upper left exposure is completed as shown in FIG. 9
Is repeated to move the wafer stage WST to the wafer exchange position. It can be seen from FIGS. 11 and 12 that the above-described efficient stepping control is performed during the above-described alternate scanning.

The reticle R and the wafer W are synchronously moved to the above-described shot area on the wafer W, and the pattern of the reticle R is sequentially transferred to a plurality of shot areas S1, S2, S3,. In the step-and-scan scanning exposure method, any two shot areas on the wafer W to which the pattern of the reticle R is transferred by the reciprocating movement of the reticle R, for example, the shots S1 and S
It is desirable to move the wafer W without stopping between the two scanning exposures. In this case, since the wafer W does not stop between adjacent areas on the wafer W where the pattern of the reticle R is sequentially transferred, for example, between the scanning exposures of the shots S1 and S2, the throughput is further improved for that portion. Because.

In this sense, the wafer W is kept in at least one of the scanning direction and the non-scanning direction of the wafer W until the scanning exposure of the last shot area on the wafer W to which the pattern of the reticle R is to be transferred is completed. More preferably, the velocity component is moved so as not to become zero. In such a case, as a result, the wafer is not stopped while scanning exposure of the step-and-scan method is performed on all of the plurality of shot areas, so that the throughput is most improved.

As described above, in the scanning exposure apparatus 10 of the present embodiment, the pre-scan by the wafer advance (acceleration time) before exposure of the reticle R and the wafer W, and the uniform speed movement time after exposure of the wafer. Stepping in the non-scanning direction (non-scanning direction) of the wafer for exposing the next shot in synchronization with the overscan due to the deceleration time,
Since the stepping operation in the non-scanning direction ends before the settling time before the wafer pre-scan shifts to the exposure operation, the pre-scan and pre-scan times before and after the scan are reduced to the stepping time for stepping to the next shot. It is possible to completely overlap, and it is possible to improve the throughput as compared with the conventional example in which the prescan and overscan operations and the stepping operation for stepping to the next shot are performed separately. Further, only the synchronous control of the wafer and the reticle in the scanning direction needs to be performed in the settling time, so that the settling time can be shortened as a result, and the throughput can be improved accordingly.

In this embodiment, the non-scanning direction acceleration of the portion corresponding to overscan due to the constant speed movement time and the deceleration time after exposure of the wafer is the same as that of the portion corresponding to prescan by wafer advance (acceleration time). Control is also possible in which the absolute value is larger than the negative acceleration in the non-scan direction, so that the body shake etc. due to high acceleration can be completely attenuated before the settling time for the synchronous control, so the controllability is improved accordingly. Thus, the throughput can be improved.

Further, the scanning type exposure apparatus 1 according to the present embodiment
According to 0, the position of the wafer W in the non-scanning direction at the time of exposure is set to the first and third optical axes in two different directions forming angles of θ1 and θ2 with respect to the Y-axis which is the scanning direction.
The position of the wafer W in the scanning direction is measured by the second interferometer 76Y having a length measuring axis in the Y-axis direction, and is obtained by calculation based on the measured values of the interferometers 76X1 and 76X2. The substrate table TB (therefore, the wafer stage WS
T) is triangular (in the above embodiment, equilateral triangular)
It becomes possible to. As a result, as shown in FIG. 13, even at the time of high acceleration / deceleration and maximum speed increase, the wafer stage WST
, While improving the footprint,
Throughput can be improved. FIG. 13 is a graph showing the deterioration of the moving mirror distance Dx and Dy for preventing the vignetting of the optical axis of the interferometer, which is indicated by an arrow (→) in the figure due to the multi-axis interferometer and the prescan and overscan. The square stage st3 is significantly larger than the minimum required square stage st1 for holding a wafer, whereas the stage WST of the present embodiment has the same Dx and Dy distance deterioration. This indicates that the stage shape needs to be much smaller than that of the square stage st3.

Further, since the yawing of wafer stage WST is calculated based on the measurement value of second interferometer 76Y for measuring the position in the scanning direction, the yawing amount is used as a reticle R error as a wafer stage rotation error during exposure. Can be corrected on the side of the reticle stage that holds the rotation angle, so that a rotation control mechanism is not required for the wafer stage WST, and the weight of the wafer stage can be reduced accordingly.

The first and third interferometers 76X1, 76X
The extended intersection of each one optical axis (first and third length measuring axes) of X2 coincides with the optical axis of the projection optical system PL, and the other optical axis (second measuring axis and fourth length axis) respectively. Since the intersection of the extended length measurement axis) coincides with the detection center of the alignment optical system ALG, the stage position without Abbe error can be measured even during exposure and alignment, and the overlay accuracy is improved.

The first, second and third interferometers measure the distances to the first, second and third reflecting surfaces formed on different side surfaces of wafer stage WST holding wafer W, respectively. At the time of exposure around the wafer stage, the prescan distance based on the settling time until the wafer approaches and moves at a constant speed during the relative scanning of the reticle R and the wafer W, and the overscan based on the constant speed movement time and the deceleration time after the exposure of the wafer W The acceleration, maximum speed, and settling time of the wafer stage WST are determined so that the optical axis of each interferometer does not deviate from the different first, second, and third reflecting surfaces of the wafer stage WST depending on the distance. There is no need to extend the reflective surface extra. Therefore, since the reflecting surface can be set within the range of the three side surfaces of the wafer stage (substrate table TB), the balance of the wafer stage WST is improved, and the stage rigidity can be increased. As a result, the focus of the wafer stage can be improved. , The tilt control response can be improved.

The first, second, and third interferometer optical axes are different from each other on the wafer stage.
And the reference mark plate FM and the aerial image detector KES for performing baseline measurement, imaging characteristic measurement, and irradiation amount measurement are arranged at positions on the wafer stage that do not deviate from the third reflection surface. Eliminating the need to extend the moving mirror (or reflecting surface) for measurement by the FM and the aerial image detector KES also leads to a reduction in the weight of the wafer stage WST.

Also, the movable surface plate 38 provided with a drive system for driving the wafer stage WST is configured to move in accordance with the reaction force accompanying the acceleration / deceleration during the movement of the wafer stage WST. The offset load due to the movement of the center of gravity of the WST can be canceled by the movement of the center of gravity of the movable platen 38, thereby reducing the load on the vibration isolator 20 and minimizing the distortion of the body due to the offset load. Reticle R
And the positioning accuracy of the wafer W can be improved.

The movable surface plate 38 can be driven and controlled at a response frequency of several Hz, and is driven and controlled so as to cancel the reaction force during acceleration / deceleration of the movement of the wafer stage WST (free movement). In addition, the response frequency can be controlled so that the movable platen 38 does not move in any direction by the stage posture (unbalanced load), so that the position of the reticle can be changed and the unbalanced load due to environmental change can be prevented. It becomes possible.

Further, since the weight of wafer stage WST is set so as to be 1/9 or less of the weight of movable surface plate 38, the movement of movable surface plate 38 due to acceleration / deceleration during movement of wafer stage WST is reduced. The moving distance according to the force becomes 1/10 or less of the moving distance of wafer stage WST, and the necessary moving range of movable table 38 can be set small.

Further, the response frequency of the movable surface plate 38 before exposure and alignment that requires position control accuracy and the other response frequencies are variable. The position of the movable platen 38 is corrected to a predetermined position during a driving operation other than exposure and alignment that requires position control accuracy. The distance that the platen 38 moves in the reverse direction can be reduced by one digit or more. That is, in addition to being able to control with high accuracy at the time of exposure and alignment, it is possible to reset the position of the movable platen 38 to an arbitrary position under other conditions, and to reduce the footprint. it can.

In the above embodiment, the scanning exposure method according to the present invention has been described in detail with reference to FIGS. 8A to 8C. However, it goes without saying that the present invention is not limited to this.
To describe another example using the same reference numerals as those in the above description, after the scanning exposure of the shot S1 is completed, the wafer W is decelerated until the moving speed of the wafer W in the scanning direction becomes zero, while intersecting the scanning direction. Move in the direction of shot S2
Before the scanning exposure, the wafer W may be moved in a direction crossing the scanning direction while being accelerated. With this configuration, after the scanning exposure of the shot S1 is completed, the wafer W is moved along the V-shaped path, so that the wafer W is moved along the path closest to the shortest distance, and the throughput can be improved accordingly. Become. Alternatively, during the deceleration of the wafer W after the scanning exposure of the shot S1, and the wafer W before the scanning exposure of the shot S2.
The wafer W may be moved in a direction intersecting the scanning direction and the non-scanning direction during the acceleration. Even in such a case, as a result, the wafer W is moved along the V-shaped path, so that the wafer is moved along a path that is close to the shortest distance, and the throughput can be improved accordingly.

In these cases, too, the wafer W
Needless to say, it is desirable to move without stopping between the scanning exposure of one and the scanning exposure of the shot S2.

In the above embodiment, an equilateral triangular stage is employed as wafer stage WST, and wafer stages WST are respectively adjusted from three different directions.
The case where the interferometer system including the first to third interferometers for measuring the position of the ST is adopted has been described. However, this is based on the viewpoint of more effectively achieving the improvement of the throughput which is the object of the present invention. Therefore, it is needless to say that the present invention is not limited to this. That is, the present invention can be suitably applied to a normal square or rectangular wafer stage similarly to the above embodiment,
The effect of improving the throughput can be sufficiently obtained to some extent.

Further, in the above embodiment, the case where wafer stage WST includes moving stage 52, leveling drive mechanism, substrate table TB, and the like has been described. However, the present invention is not limited to this. A plate-like member may be used as the substrate stage. Even if such a plate-shaped member is used, a so-called two-dimensional plane motor (having a Z drive coil) or the like can be used for tilt drive and Z-direction drive with respect to the XY plane.

In the above embodiment, the case where all of the first to third reflecting surfaces 60a, 60b and 60c are formed on the side surface of the substrate table TB by mirror finishing has been described.
The present invention is not limited to this, and it is a matter of course that any one or two of them may be constituted by a reflecting surface of a moving mirror composed of a plane mirror.

In the above embodiment, the projection optical system PL
As described above, a case was described in which a reduction projection lens composed of only a refractive optical element (lens) using quartz or fluorite as an optical glass material was used. However, the present invention is not limited to this and other types of projection lens are used. The same applies to an optical system. Therefore, another type of projection optical system will be briefly described with reference to FIG.

FIG. 14A shows a reduction projection optical system combining refracting optical elements (lens systems) GS1 to GS4, concave mirrors MRs, and a beam splitter PBS. This point is reflected by the concave mirror MRs via the large beam splitter PBS, returned to the beam splitter PBS again, formed into an image on the projection image plane PF3 (wafer W) by obtaining a reduction ratio by the refraction lens system GS4. It is disclosed in Japanese Unexamined Patent Publication No. 3-282527.

FIG. 14B shows a reduction projection optical system in which refractive optical elements (lens systems) GS1 to GS4, a small mirror MRa, and a concave mirror MRs are combined.
The image forming light beam from the reticle R is transmitted to the lens systems GS1 and GS.
2. First imaging system PL of approximately equal magnification composed of concave mirrors MRs
1. Small mirror MRa with eccentric arrangement and lens system GS
And GS4, which has a substantially desired reduction ratio.
An image is formed on a projection image plane PF3 (wafer W) through an imaging system PL2.
No. 6,086,045.

In the above embodiment, the case where the off-axis alignment sensor ALG is used as the alignment optical system has been described.
Of course, an on-axis alignment optical system such as a (through-the-lens) type may be used. In such cases,
Similarly to the second interferometer 76Y, the first and third interferometers 76
The projection optical system PL is located at a position where the extension of the center line of the two light beams (length measuring beams) emitted from X1 and 76X2 intersects.
When the wafer stage yawing is determined based on the average value of the difference between the results measured with all three biaxial light beams, the yawing measurement accuracy is improved to 1 / √3.

By the way, the present inventor provided two wafer stages (substrate stages) mainly from the viewpoint of improving the throughput at the time of double exposure, during exposure operation on a wafer on one of the wafer stages. An exposure apparatus that performs other operations such as wafer exchange and alignment on the other wafer stage in parallel has been proposed (Japanese Patent Laid-Open No.
-163097, JP-A-10-163098, etc.). It is apparent that the exposure apparatuses described in these publications can improve the throughput further by using ordinary exposure instead of double exposure as compared with the case of double exposure. Further, when the scanning exposure method described in the first embodiment is adopted in the exposure apparatuses described in these publications, the throughput is further improved in both the normal exposure and the double exposure. It is possible.

However, in such a case, Japanese Patent Application Laid-Open
As described in Japanese Patent Application Laid-Open No. 0-163098, in addition to control measures such as performing operations on one wafer stage side and the other wafer stage side such that operations that do not affect each other are synchronized with each other. Since the wafer stage must be controlled as described in the first embodiment, the control program of the stage control system becomes very complicated. The following second embodiment has been made to improve such inconvenience.

<< Second Embodiment >> Next, a second embodiment of the present invention will be described with reference to FIGS.

FIG. 15 shows a schematic configuration of an exposure apparatus 110 according to the second embodiment. Here, for the same or equivalent parts as in the first embodiment described above,
The same reference numerals are used and the description is simplified or omitted. The exposure apparatus 110 is a so-called step-and-scan type scanning exposure type projection exposure apparatus.

Exposure apparatus 110 is a stage apparatus provided with two square wafer stages WST1 and WST2 as first movable bodies that respectively hold wafers W1 and W2 as substrates and move independently in two-dimensional directions. 101,
The projection optical system PL disposed above the stage apparatus 101 and the reticle R as a mask above the projection optical system PL are mainly used in a predetermined scanning direction, here, the Y-axis direction (FIG. 1).
5, a reticle drive mechanism that drives the reticle R from above, a control system that controls these components, and the like.

The stage device 101 includes a surface plate 22 forming the gantry (first column) 16,
2, a rectangular movable platen 138 as a second movable body supported to be relatively movable in the XY plane, and the movable platen 138 on the movable platen 138 in the XY plane. The two wafer stages WST supported so as to be relatively movable.
1, WST2, and an interferometer system for measuring the positions of wafer stages WST1, WST2. As the movable surface plate 138, a structure similar to that of the movable surface plate 38 of the first embodiment described above is used. In addition,
The role of the movable platen 138 will be described later.

Wafer stages WST1 and WST2 are planar magnetic levitation linear actuators 4 as driving devices provided on movable table 138 below projection optical system PL.
2a and 42b, respectively, and are driven independently of each other in an XY two-dimensional plane orthogonal to the optical axis AX of the projection optical system PL. Further, the movable type platen 138 includes wafer stages WST1 and WST1.
Similarly to ST2, it is levitated and supported by a planar magnetic levitation type linear actuator 44 as a second driving device provided on the surface plate 22, and is freely driven in an XY two-dimensional plane. The planar magnetic levitation linear actuators 42a, 42b, and 44 are shown in FIG.
5 is controlled by the stage controller 160.

On wafer stages WST1 and WST2, wafers W1 and W2 are placed via a wafer holder (not shown).
Are fixed by electrostatic suction or vacuum suction. The wafer holder is minutely driven in a Z-axis direction and a θ-direction (a rotation direction around the Z-axis) orthogonal to the XY plane by a Z · θ drive mechanism (not shown). Further, on the upper surface of wafer stages WST1 and WST2, fiducial mark plates FM1 and FM2 on which various fiducial marks are formed are installed so as to be approximately the same height as wafers W1 and W2. These reference mark plates FM1 and FM2 are used, for example, when detecting the reference position of each wafer stage.

As shown in FIG. 16, a surface 120 on one side in the X-axis direction (left side surface in FIG. 15) of wafer stage WST1 and a surface on one side in the Y-axis direction (rear surface in FIG. 15). Reference numeral 121 denotes a mirror-finished reflection surface. Similarly, a surface 122 on the other side in the X-axis direction (the right side surface in FIG. 15) of the wafer stage WST2 and a surface 123 on one side in the Y-axis direction The mirror surface is a reflective surface. The interferometer beams of the respective measurement axes (BI1X, BI2X, etc.) constituting the interferometer system described later are projected on these reflecting surfaces, and the reflected light is received by the interferometers, whereby the reference of each reflecting surface is obtained. Position (generally, a fixed mirror is placed on the side of the projection optical system or the side of the alignment optical system,
Then, the displacement from the reference plane is measured, whereby the two-dimensional positions of the wafer stages WST1 and WST2 are respectively measured. The configuration of the measurement axis of the interferometer system will be described later in detail.

On both sides of the projection optical system PL in the X-axis direction, as shown in FIG. 15, off-axis alignment systems 124a and 124b having the same function.
Are located at the same distance from the optical axis center of the projection optical system PL (coincident with the projection center of the reticle pattern image). These alignment systems 124a,
124b is an LSA (Laser Step Alignment) system, FI
A (Filed Image Alignment) system, LIA (Laser Inte
It has three types of alignment sensors of the rferometric Alignment type, and can measure the position of the reference mark on the reference mark plate and the alignment mark on the wafer in the X and Y two-dimensional directions.

Here, the LSA system is the most versatile sensor that irradiates a laser beam onto a mark and measures the position of the mark by using diffracted and scattered light. Is done. The FIA system is a sensor that illuminates a mark with broadband (broadband) light such as a halogen lamp and measures the mark position by processing the mark image, and is used effectively for an asymmetric mark on an aluminum layer or a wafer surface. You. In addition, LIA system
A sensor that irradiates a diffraction grating mark with laser light whose frequency is slightly changed from two directions, interferes the two generated diffraction lights, and detects mark position information from its phase. Used effectively for rough wafers.

In the second embodiment, these three types of alignment sensors are properly used according to the purpose, and a so-called search for detecting the positions of three one-dimensional marks on the wafer and measuring the approximate position of the wafer is performed. Alignment and fine alignment for accurately measuring the position of each shot area on the wafer are performed.

In this case, alignment system 124a is used for position measurement of an alignment mark on wafer W1 held on wafer stage WST1 and a reference mark formed on reference mark plate FM1. Further, alignment system 124b is used for position measurement of alignment marks on wafer W2 held on wafer stage WST2 and reference marks formed on reference mark plate FM2.

The alignment systems 124a and 124
The information from each of the alignment sensors constituting b is A / D converted by the alignment control device 180, and the digitized waveform signal is subjected to arithmetic processing to detect the mark position. The result is sent to main controller 190, and from main controller 190, stage controller 160 is controlled in accordance with the result.
, A synchronous position correction at the time of exposure or the like is instructed.

Although not shown, each of the projection optical system PL and the alignment systems 124a and 124b is used to check the in-focus position as disclosed in the above-mentioned JP-A-10-163098. auto focus/
An auto-leveling (AF / AL) measurement mechanism is provided.

Next, the reticle driving mechanism will be described with reference to FIG.
This will be described with reference to FIG.

The reticle driving mechanism comprises a reticle stage RST that can move in the two-dimensional XY directions while holding a reticle R on the reticle base platen 28, and a linear motor (not shown) that drives the reticle stage RST. And a reticle laser interferometer 30 that measures the position of the reticle stage RST via a movable mirror 31 fixed to the reticle stage RST.

More specifically, as shown in FIG. 16, on the reticle stage RST, two reticles R1 and R2 can be set in series in the scanning direction (Y-axis direction). This reticle stage RST
Is floated and supported on a reticle base surface plate 28 via an air bearing or the like (not shown) so that a driving system 29 performs minute driving in the X-axis direction, minute rotation in the θ direction, and scanning driving in the Y-axis direction. Has become. The drive system 29 is
Although the mechanism uses a linear motor as a drive source, it is shown as a simple block in FIG. 15 for convenience of illustration and description. For this reason, the reticles R1 and R2 on the reticle stage RST are selectively used, for example, at the time of double exposure, and any of the reticles can be synchronously scanned with the wafer side.

On reticle stage RST, a parallel plate moving mirror 31X made of the same material (for example, ceramic) as reticle stage RST is provided at the other end in the X-axis direction.
Is extended in the Y-axis direction, and a reflection surface is formed on the other surface of the movable mirror 31X in the X-axis direction by mirror finishing. The measurement axis BI6 is directed toward the reflection surface of the movable mirror 31X.
An interferometer beam from an interferometer (not shown) indicated by X is emitted, and the interferometer receives the reflected light and measures the relative displacement with respect to a reference plane, thereby measuring the position of the reticle stage RST. I have. Here, the interferometer having the measurement axis BI6X actually has two interferometer optical axes that can be measured independently, and the X axis of the reticle stage
Axial position measurement and yawing amount measurement are possible. The measured values of the interferometer having the length measuring axis BI6X are measured by the length measuring axes BI1X, BI1
Based on yawing information and X position information of wafer stages WST1 and WST2 from interferometers 116 and 118 having 2X, rotation control of reticle stage RST in a direction for canceling relative rotation (rotation error) between the reticle and the wafer, X Used to perform direction synchronization control.

On the other hand, on the other side in the Y-axis direction (scanning direction) of reticle stage RST (on the front side in FIG. 15), a pair of corner cube mirrors 3 are provided.
1 _y1 and 31 _y2 are installed. Then, from a pair of double-pass interferometers (not shown), the measurement axes BI7Y and BI7Y are shown in FIG. 16 for these corner cube mirrors 31 _y1 and 31 _y2 .
An interferometer beam indicated by BI8Y is radiated, and a corner cube mirror 3
1 _y1 , 31 _y2 , each reflected light reflected there returns along the same optical path, is received by each double-pass interferometer, and each corner cube mirror 31 _y1 ,
A relative displacement from a reference position _31y2 (a reflection surface on the reticle base surface plate 28 at the reference position) is measured. The measured values of these double-pass interferometers are shown in FIG.
The reticle stage RST is supplied to the stage controller 160 of No. 5 and the position of the reticle stage RST in the Y-axis direction is measured based on the average value. The information on the Y-axis direction position is calculated by calculating the relative position between the reticle stage RST and the wafer stage WST1 or WST2 based on the measurement value of the interferometer having the wafer-side length measuring axis BI3Y, and performing scanning during scanning exposure based on this. It is used for synchronous control of the reticle in the direction (Y-axis direction) and the wafer.

As described above, in the second embodiment, the interferometer indicated by the length measuring axis BI6X and the length measuring axes BI7Y and BI7Y
Reticle laser interferometer 3 shown in FIG. 15 by a total of three interferometers of a pair of double-pass interferometers indicated by 8Y.
0 is configured.

Next, wafer stages WST1, WST2
An interferometer system that manages the position of is described with reference to FIGS.

As shown in these figures, along the X-axis passing through the projection center of projection optical system PL and the detection centers of alignment systems 124a and 124b, a surface on one side in the X-axis direction of wafer stage WST1 is disposed. Is the interferometer 1 in FIG.
An interferometer beam indicated by the measurement axis BI1X from the wafer stage WST2 is similarly irradiated along the X axis.
15 is irradiated with an interferometer beam indicated by a measurement axis BI2X from the interferometer 118 in FIG. The interferometers 116 and 118 measure the relative displacement of each reflecting surface from the reference position by receiving these reflected lights, and measure the positions of the wafer stages WST1 and WST2 in the X-axis direction. .

Here, the interferometers 116 and 118 are shown in FIG.
As shown in the figure, the three-axis interferometer having three optical axes enables tilt measurement and θ measurement in addition to the measurement of the wafer stages WST1 and WST2 in the X-axis direction. In this case, θ of wafer stages WST1 and WST2
Since a not-shown θ stage for rotation and a Z-leveling stage (not shown) for performing minute drive and tilt drive in the Z-axis direction are actually below the reflecting surface (120 to 123), the tilt of the wafer stage is All of the driving amounts during the control can be monitored by these interferometers 116 and 118.

It should be noted that each interferometer beam of length measuring axes BI1X and BI2X always strikes wafer stages WST1 and WST2 in the entire movement range of wafer stages WST1 and WST2. Therefore, in the X-axis direction, At the time of exposure using projection optical system PL, alignment system 1
At any time such as when using 24a and 124b, the positions of wafer stages WST1 and WST2 are aligned with length measurement axes BI1X,
It is managed based on the measured value of BI2X.

As shown in FIGS. 16 and 17, each of an interferometer 132 having a length measuring axis BI3Y perpendicular to the X axis at the projection center of the projection optical system PL, and alignment systems 124a and 124b, respectively. Interferometers 131 and 133 having length measuring axes BI4Y and BI5Y respectively perpendicularly intersecting the X axis at the detection center are provided.

In the case of this embodiment, the position measurement in the Y direction of wafer stages WST1 and WST2 at the time of exposure using projection optical system PL requires the projection center of projection optical system PL, that is, the length measurement axis passing through optical axis AX. The measurement value of the BI3Y interferometer 132 is used, and in the Y direction position measurement of the wafer stage WST1 when the alignment system 124a is used, the detection center of the alignment system 124a, that is, the interference of the length measurement axis BI4Y passing through the optical axis SX. The measurement value of the total 131 is used, and the wafer stage WST2 when the alignment system 124b is used.
In the Y direction position measurement, the measurement value of the detection center of the alignment system 124b, that is, the interferometer 133 of the length measurement axis BI5Y passing through the optical axis SX is used.

Accordingly, the long axis of the interference measurement in the Y-axis direction deviates from the reflection surface of wafer stage WST1 or WST2 depending on each use condition, but at least one of the length measurement axes, ie, length measurement axes BI1X and BI2X, Of the wafer stage WST1 and WST2, the Y-side interferometer can be reset at an appropriate position where the optical axis of the interferometer to be used is on the reflection surface.

Note that the length measurement axes BI3Y and B
I4Y, BI5Y interferometers 132, 131, 133
Is a two-axis interferometer having two optical axes, and can perform tilt measurement in addition to the measurement of the wafer stages WST1 and WST2 in the Y-axis direction. In this embodiment, a total of five interferometers 116, 118, 131, 132, and 133 constitute an interferometer system that manages the two-dimensional coordinate position of wafer stages WST1 and WST2.

Further, main controller 19 shown in FIG.
0 is provided with a memory 191 storing a conditional expression (for example, an interference condition) for managing the movement of the wafer stages WST1 and WST2.

In the second embodiment, as will be described later, while one of wafer stages WST1 and WST2 is executing an exposure sequence, the other is for wafer exchange.
A wafer alignment sequence is performed. At this time, the stage controllers 160 in accordance with a command from the main controller 190 based on the output values of the interferometers so that the two stages do not interfere with each other.
2 is managed.

Next, the role of the movable surface plate 138 and a control method thereof will be briefly described. This movable surface plate 1
The stage 38 basically has the same role as the movable platen 38 of the first embodiment described above, and is similarly controlled by the stage controller 160.

That is, on the upper surface of the movable platen 138,
A plurality of coils (not shown) forming the planar magnetic levitation linear actuators 42a and 42b are stretched in the XY two-dimensional directions together with permanent magnets (not shown) provided on the lower surfaces of the wafer stages WST1 and WST2. The wafer stages WST1 and WST2 are levitated above the movable platen 138 by the planar magnetic levitation linear actuators 42a and 42b, and the wafer stages WST1 and WST2 of the coils oppose each other. By controlling the current flowing through the partial coils, the coils are independently driven in an arbitrary two-dimensional direction.

The movable surface plate 138 is levitated above the surface plate 22 by a planar magnetic levitation linear actuator 44 in the same manner as the movable surface plate 38 of the first embodiment. It is configured to be driven in an arbitrary two-dimensional direction by controlling the current flowing through the coil.

In this case, wafer stages WST1, WS
T2 and movable platen 138, movable platen 138 and platen 22
Means that the friction between them is very small because they are not in contact with each other.
The momentum conservation law is established for the entire system including the WST 2 and the movable surface plate 138. That is, wafer stage WST1
When one of WST2 and WST2 moves, it is completely the same as in the first embodiment, and wafer stages WST1 and WST2 move.
When ST2 moves at the same time, the movable platen 13 is moved by the reaction force against the resultant force of the driving forces of these stages.
This is because 8 moves.

Also in the second embodiment, as in the first embodiment, the wafer stage acceleration, maximum speed,
In order to suppress the deterioration of the footprint to one digit or less, the mass m of the wafer stages WST1 and WST2 and the movable platen 13
8 is set so that the ratio of the mass M of m: M is 1: 9 or less, that is, the weight of the wafer stages WST1 and WST2 is 1/9 or less of the weight of the movable platen 138. If the masses of wafer stage WST1 and wafer stage WST2 are different, movable surface plate 138
Is preferably set to at least about nine times the mass of the lighter wafer stage as a reference.

In order to reduce the required stroke of the movable surface plate 138, the stage control device 160 determines the control response to the planar magnetic levitation linear actuator 44 for driving the movable surface plate 138 during exposure, alignment, and other operations. It is made to be variable at the time of.

Therefore, at the time of exposure, wafer stage WS
The reticle stage RST moves synchronously with the T1 or WST2. However, if the control response of the planar magnetic levitation linear actuator 44 for driving the movable platen 138 is controlled at several Hz, the wafer is controlled at several tens of Hz. Stage WST
1. The reaction force of the planar magnetic levitation linear actuators 42a and 42b for driving the WST2 on the movable surface plate 138 can hardly be followed.
Moves freely and absorbs the reaction force, and the influence of the reaction force does not reach the outside.

Also, in stage control device 160, the position of reticle stage RST, wafer stage WST1,
When the exposure apparatus main body 12 is entirely tilted due to a change in the position of the WST 2, the planar magnetic levitation linear actuator 4
By controlling the control response at 4 Hz at several Hz, the low-frequency position shift in which the movable platen 138 moves in the tilt direction is prevented.

Also in the present embodiment, the linear encoder 45 as a position measuring device for detecting the position of the movable platen 138 relative to the platen 22 in the X and Y directions.
By the feedback control using FIG. 15 (see FIG. 15), the stage control device 160 controls the response frequency of the planar magnetic levitation linear actuator 44 for driving the movable surface plate 138 at a predetermined timing as in the first embodiment. The movement amount of the movable platen 138 is reduced (maintained at a substantially predetermined position) by an operation such as raising the frequency to several tens Hz.

The control system mainly includes a main controller 190 for controlling the entire apparatus as a whole, and an exposure controller 170, a stage controller 160, and the like under the main controller 190.

Here, the operation of the exposure apparatus 110 of the present embodiment at the time of exposure will be described focusing on the operation of each component of the control system.

[0307] Prior to the start of the synchronous scanning of the reticle R and the wafer (W1 or W2), the exposure amount control device 170 controls the illumination optical system 1 via a shutter drive unit (not shown).
The shutter (not shown) in 8 is opened.

After that, the stage control device 160
Synchronous scanning (scan control) of reticle R and wafer (W1 or W2), that is, reticle stage RST and wafer stage (WST1 or WST2) is started according to an instruction from main controller 190. This synchronous scanning is performed by the aforementioned measuring axis BI3Y and measuring axis BI1X of the interferometer system.
Or the measuring axis B of BI2X and reticle laser interferometer 30
While monitoring the measured values of I7Y, BI8Y and the measurement axis BI6X, the stage controller 160 controls the reticle driver 29 and the drive system of the wafer stage (the planar magnetic levitation linear actuator 42a or 42b).

Then, when both stages are controlled at a constant speed within a predetermined allowable error, the exposure amount control device 170 starts pulse emission of the excimer laser. Thus, the illumination light from the illumination optical system 18 illuminates the rectangular illumination area IA of the reticle R on which the pattern is chromium-deposited on the lower surface, and an image of the pattern in the illumination area is projected by the projection optical system PL. Projection exposure is performed on a wafer (W1 or W2), which is reduced to ４ (or ５) times and has a surface coated with a photoresist. Here, FIG.
As is clear from FIG. 5, the slit width in the scanning direction of the illumination area IA is narrower than the pattern area on the reticle R, and the reticle R and the wafer (W1 or W2) are synchronously scanned as described above, so that the pattern An image of the entire surface is sequentially formed in a shot area on the wafer.

Here, at the same time as the start of the pulse emission described above, the exposure control device 170 drives the vibrating mirror 18D so that the pattern area on the reticle R becomes completely the illumination area I.
A (see FIG. 16), that is, until the entire image of the pattern is formed in the shot area on the wafer.
By performing this control continuously, unevenness of interference fringes generated in the two fly-eye lens systems is reduced.

The movable blind 18M is driven in synchronization with the scanning of the reticle R and the wafer W so that the illumination light does not leak outside the light-shielding area on the reticle at the shot edge during the scanning exposure. Drive control is performed by the stage control device 43, and a series of these synchronous operations are managed by the stage control device 160.

During the above-mentioned scanning exposure (scanning exposure), as disclosed in Japanese Patent Application Laid-Open No. 10-163098, the main controller 190 or the exposure controller 170 sets the integrated exposure corresponding to the resist sensitivity. Performs all calculations on the variable amount of irradiation energy and oscillation frequency, and controls the dimming system provided in the light source unit to change the irradiation energy and oscillation frequency and control the shutter and vibration mirror. It is configured.

Further, in the main control device 190, for example,
When correcting the movement start position (synchronous position) of the reticle stage and the wafer stage that perform synchronous scanning during scan exposure, a stage control device 160 that controls movement of each stage.
Is instructed to correct the stage position according to the correction amount.

Further, in the exposure apparatus 110 of the present embodiment,
A first transfer system for exchanging wafers with wafer stage WST1 and a second transfer system for exchanging wafers with wafer stage WST2 are provided.

As shown in FIG. 18, the first transfer system exchanges wafers with wafer stage WST1 at the wafer loading position on the left as described later. The first transport system is attached to a first loading guide 182 extending in the Y-axis direction, a first slider 186, a second slider 187, and a first slider 186 moving along the loading guide 182. A first wafer loader including a first unload arm 184, a first load arm 188 attached to a second slider 187, and the like, and three vertical moving members provided on wafer stage WST1 And a first center-up 181 composed of

Here, the operation of exchanging wafers by the first transfer system will be briefly described.

Here, as shown in FIG. 18, wafer stage WST at the left wafer loading position
A case where the wafer W1 ′ on the wafer 1 is replaced with the wafer W1 carried by the first wafer loader will be described.

First, main controller 190 turns off the vacuum of the wafer holder (not shown) on wafer stage WST1 via a switch (not shown), and releases the suction of wafer W1 '.

Next, main controller 190 drives center-up 181 upward by a predetermined amount via a center-up drive system (not shown). Thereby, the wafer W1 'is lifted to a predetermined position. In this state, main controller 190
Then, the movement of the first unload arm 184 is instructed to a wafer loader control device (not shown). As a result, the first slider 186 is driven and controlled by the wafer loader control device, and the first unload arm 184 moves along the loading guide 182 to a position above the wafer stage WST1 and is located immediately below the wafer W1 ′.

In this state, main controller 190 drives center-up 181 to descend to a predetermined position. Since the wafer W1 'is transferred to the first unload arm 184 while the center-up 181 is descending, the main controller 190 instructs the wafer loader controller to start vacuuming the first unload arm 184. As a result, the wafer W1 ′ is placed on the first unload arm 184.
Is held by suction.

Next, main controller 190 instructs wafer loader controller to retract first unload arm 184 and to start moving first load arm 188. Accordingly, the first unload arm 184 starts moving in the −Y direction in FIG. 18 integrally with the first slider 186, and at the same time, the second slider 187 and the first load arm 188 holding the wafer W1 Movement is integrally started in the + Y direction. Then, when the first load arm 188 comes above the wafer stage WST1, the second slider 187 is stopped by the wafer loader control device, and the vacuum of the first load arm 188 is released.

In this state, main controller 190 drives center-up 181 to move up, and center-up 181 lifts wafer W1 from below. Next, main controller 190 instructs wafer loader controller to retract the load arm. Thereby, the second slider 18
7 starts moving integrally with the first load arm 188 in the −Y direction, and the first load arm 188 is retracted. At the same time that the first load arm 188 starts retreating, main controller 190 starts lowering drive of center-up 181 to place wafer W1 on a wafer holder (not shown) on wafer stage WST1, and reduces the vacuum of the wafer holder. turn on. Thus, a series of wafer exchange sequences is completed.

In the second transfer system, similarly, as shown in FIG. 19, the wafer is exchanged with wafer stage WST2 at the right wafer loading position in the same manner as described above. The second transport system includes a second loading guide 192 extending in the Y-axis direction, a third slider 196 and a fourth slider 200 moving along the second loading guide 192, and a third slider 1
96, a second unload arm 194 attached to
A second wafer loader including the second load arm 198 and the like attached to the fourth slider 200 and a second center-up (not shown) provided on the wafer stage WST2.

Next, the parallel processing by the two wafer stages WST1 and WST2 will be described with reference to FIGS.

FIG. 18 shows that while wafer W2 on wafer stage WST2 is being exposed through projection optical system PL, wafer stage WST1 and first transfer are performed as described above at the left loading position. FIG. 3 is a plan view showing a state where a wafer is exchanged with the system. In this case, an alignment operation is performed on wafer stage WST1, following the wafer exchange, as described later. In FIG. 18, position control of wafer stage WST2 during the exposure operation is performed based on the measured values of measurement axes BI2X and BI3Y of the interferometer system, and the position of wafer stage WST1 at which the wafer exchange and alignment operation are performed. The control is performed by the measurement axis BI1 of the interferometer system.
This is performed based on the measured values of X and BI4Y.

At the left loading position shown in FIG. 18, the reference mark on reference mark plate FM1 of wafer stage WST1 is arranged immediately below alignment system 124a. Therefore, main controller 190
Then, the reference mark plate FM is adjusted by the alignment system 124a.
Before measuring the fiducial mark on 1, the reset of the interferometer of the length measurement axis BI4Y of the interferometer system is performed.

[0327] Subsequent to the above-described wafer exchange and resetting of the interferometer, search alignment is performed. The search alignment performed after the wafer exchange is the wafer alignment
This is pre-alignment performed again on wafer stage WST1 because a positional error is large only by pre-alignment performed during the transfer of wafer 1. Specifically, the positions of three search alignment marks (not shown) formed on wafer W1 mounted on stage WST1 are measured using an LSA system sensor or the like of alignment system 124a, and the measurement is performed. Based on the result, X, Y,
The alignment in the θ direction is performed. The operation of each unit during the search alignment is controlled by main controller 190.

After completion of the search alignment, fine alignment for obtaining the arrangement of each shot area on the wafer W1 using EGA is performed here. Specifically, the wafer stage WST1 is sequentially controlled based on the designed shot array data (alignment mark position data) while controlling the position of the wafer stage WST1 by an interferometer system (length measuring axes BI1X and BI4Y). While moving, the position of the alignment mark of a predetermined sample shot on the wafer W1 is measured by a FIA sensor or the like of the alignment system 124a, and a statistical calculation by the least square method is performed based on the measurement result and the design coordinate data of the shot array. , And calculate all shot array data. The operation of each unit at the time of this EGA is controlled by main controller 190, and the above calculation is performed by main controller 190.
It is desirable that the result of this operation be converted into a coordinate system based on the reference mark position of the reference mark plate FM1.

In the case of the present embodiment, as described above, at the time of measurement by the alignment system 124a, the same AF as at the time of exposure is performed.
The position of the alignment mark is measured while performing autofocus / autoleveling by measuring / controlling the / AL mechanism, so that an offset (error) due to the posture of the stage does not occur between alignment and exposure. Can be.

While wafer exchange and alignment operations are being performed on wafer stage WST1 side, wafer stage WST2 side uses two reticles R1 and R2 to continuously perform step and step changing exposure conditions. Double exposure is performed by the AND scan method.

Specifically, fine alignment by EGA is performed in advance in the same manner as the above-described wafer W1 side, and the shot arrangement data on the wafer W2 obtained as a result (the reference alignment on the reference mark plate FM2) is obtained. Based on the mark), the inter-shot movement (stepping) operation to the adjacent shot of the wafer W2 is sequentially performed, and the above-described scan exposure is sequentially performed on each shot area on the wafer W2. During the above-mentioned movement between shots,
Movement control of wafer stage WST2 similar to that described with reference to FIGS. 8A to 8C in the first embodiment is performed.

Exposure for all shot areas on wafer W2 is continuously performed even after reticle replacement.
As a specific exposure sequence of the double exposure, for example, the wafer W
Scan exposure is sequentially performed on each of the shot areas 1 using the reticle R2, and then the reticle stage RST is moved in the scanning direction by a predetermined amount to set the reticle R1 at the exposure position. Do. At this time, reticle R2 and reticle R1 use exposure conditions (AF / AL,
Since the exposure amount and the transmittance are different, it is necessary to measure each condition at the time of reticle alignment and change the condition according to the result.

The operation of each part during the double exposure of wafer W2 is also controlled by main controller 190.

In the exposure sequence and the wafer exchange / alignment sequence performed in parallel on the two wafer stages WST1 and WST2 shown in FIG. 18, the previously completed wafer stage is in a waiting state, and both operations are performed. Is completed, the movement of wafer stages WST1 and WST2 is controlled to the position shown in FIG. Then, wafer W2 on wafer stage WST2, for which the exposure sequence has been completed, is replaced at the right loading position, and wafer W1, on wafer stage WST1, for which the alignment sequence has been completed, undergoes an exposure sequence under projection optical system PL. Will be

In the right loading position shown in FIG. 19, similarly to the left loading position, the reference mark on the reference mark plate FM2 is arranged below the alignment system 124b. Will be executed.
Of course, the reset operation of the interferometer of the length measurement axis BI5Y of the interferometer system is executed before the alignment system 124b detects a mark on the reference mark plate FM2.

The operation of resetting the interferometer by main controller 190, which is performed in the above-described series of parallel processing operations, is exactly the same as the operation disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 10-163098. Therefore, detailed description is omitted.

When two wafer stages WST1 and WST2 are used to simultaneously perform different operations as in this embodiment, the operation performed in one stage may affect the operation of the other stage (disturbance). There is. In such a case, in the exposure apparatus described in Japanese Patent Application Laid-Open No. H10-163098, two stages WST1 as disclosed in FIGS.
Since the timing of the operation performed on WST2 was adjusted, the control operation was complicated.

On the other hand, in this embodiment, as described above, since wafer stages WST1 and WST2 are arranged on surface plate 22 via movable surface plate 138, planar magnetic levitation linear actuator 42a or Any wafer stage (WST1 or WST2) depending on 42b
Is driven, the movable surface plate 138 moves due to the reaction force of the driving force, and the uneven load due to the movement of the center of gravity of the wafer stage (WST1 or WST2) is moved.
Not only can the center of gravity of the entire stage device 101 be maintained at a predetermined position, but also the planar magnetic levitation linear actuator 42
When wafer stages WST1 and WST2 are simultaneously driven by a and 42b, the eccentric load caused by the movement of the center of gravity of wafer stages WST1 and WST2 due to the reaction force corresponding to the resultant force of the driving force is caused by the movement of the center of gravity of movable platen 138. The movable surface plate 138 moves so as to cancel, and as a result, the center of gravity of the entire stage device 101 can be held at a predetermined position. Accordingly, it is not necessary to adjust the operation of the wafer stages WST1 and WST2 so that one operation does not act as a disturbance on the other, so that the control load is reduced and the position of each wafer stage is reduced. High controllability can be maintained.

When double exposure is performed using a plurality of reticles R as described above, high resolution and DOF (depth of focus) can be obtained. However, in the double exposure method, since the exposure step must be repeated at least twice, the conventional exposure apparatus has a disadvantage that the exposure time is long and the throughput is greatly reduced. On the other hand, in the second embodiment, the throughput can be greatly improved by the simultaneous parallel processing such as the exposure operation on one wafer stage and the alignment and the wafer exchange operation on the other wafer stage, so that the throughput is reduced. The high resolution and the effect of improving the DOF can be obtained without any problem.

As disclosed in JP-A-10-163098, in an exposure apparatus having a double wafer stage, for example, each processing time is set to T1 (wafer replacement time) and T2 (search alignment time). , T3 (fine alignment time), and T4 (single exposure time), when performing double exposure while processing T1, T2, T3 and T4 in parallel, for an 8-inch wafer,
Since the exposure time is longer, the exposure time becomes a constraint and the overall throughput is determined. However, in the second embodiment, the exposure time T4 is shortened by shortening the inter-shot movement time of the wafer stages WST1 and WST2. Is possible, and a double exposure with a high throughput almost equal to that of a normal single exposure can be realized.

In the second embodiment, the case where the stage apparatus according to the present invention is applied to an apparatus for exposing a wafer by using the double exposure method has been described. Can also be applied, in which case
While exposing twice with two reticles on one wafer stage side, wafer exchange and wafer alignment are performed in parallel on the other independently movable wafer stage side, so that stitching by a normal exposure apparatus is performed. Higher throughput than that of

However, the application range of the stage device according to the present invention is not limited to this, and the present invention can be suitably applied to the case of performing exposure by a single exposure method.

In the second embodiment, the case where the alignment operation, the wafer exchange operation, and the exposure operation are performed in parallel has been described. However, the present invention is not limited to this. For example, a baseline check (BCHK), a wafer exchange operation, and the like. A sequence such as a calibration performed every time is performed may be similarly processed in parallel with the exposure operation.

In the second embodiment, an exposure apparatus using a square wafer stage as the two wafer stages WST1 and WST2 has been described. However, the present invention is not limited to this. For example, as shown in FIG. Triangular wafer stages WST3 and WST4 similar to wafer stages WST1 and WST2 of the first embodiment may be arranged on movable platen 138 on platen 22. In the apparatus shown in FIG. 20, an interferometer system for measuring the positions of wafer stages WST3 and WST4 is connected to XY axes intersecting the centers of projection optical system PL and alignment optical systems 124a and 124b, as shown in FIG. Six pairs of interferometers 211, 212, 21 each having a length measuring axis inclined at a predetermined angle
3, 214, 215, and 16 may be used. In this case, interferometers 213 and 214 can control the position of wafer stage WST3 or wafer stage WST4 in the Y direction (synchronous movement direction) and the X direction (non-scanning direction) at the time of exposure with high accuracy. Also, the interferometer 211,
The position control of the wafer stage WST3 in the Y and X directions at the time of alignment performed using the alignment optical system 124a can be performed with high precision by the 212.
Further, position control of wafer stage WST4 in the Y direction and the X direction at the time of alignment performed using alignment optical system 124b by interferometers 215 and 216 can be performed with high accuracy.

In this case, a set of the interferometer 211 and the interferometer 213 or the set of the interferometer 213 and the interferometer 215
May be used instead of the above-described first interferometer 76X1, and similarly, the above-described third interferometer 76X1 may be used instead of the interferometer 212 and interferometer 214 set or the interferometer 214 and interferometer 216 set. May be used. Further, the position control of wafer stage WST4 in the Y direction is performed by the second control described above.
Is always performed using the interferometer 76Y of the
3, 214 or interferometers 215, 216 may be used simultaneously to control the position of wafer stage WST4 in the X direction at the time of exposure or alignment as in the first embodiment.

In the second embodiment, the case where the wafer stages WST1 and WST2 as the first movable bodies constituting the stage device 101 are driven by the planar magnetic levitation linear actuator has been described. Such a stage device is not limited to this, and a driving device for driving each first movable body may be a normal linear motor or the like.

In the description of the above embodiment, FIG.
(B) and (C) are used to describe a speed control method in a case where the movement trajectory of the wafer stage WST during the movement between shots is set in a U-shape as shown in FIG.
Wafer stage WST (and reticle stage RST)
In the scanning direction, the acceleration is accelerated to a target scanning speed (scan speed) at a constant acceleration, and after the scanning exposure at the target scanning speed is completed, the acceleration is decelerated at a constant acceleration (constant deceleration). B) and FIG. 8B), the throughput can be further improved by changing the method of controlling the acceleration of the reticle stage RST and the wafer stage WST in the scanning direction.

Hereinafter, the stage control system for sequentially exposing adjacent shots S1, S2, and S3 shown in FIG. 8A by alternate scan using the scanning exposure apparatus 10 of the first embodiment will be described. A stage acceleration control method will be described with reference to FIGS. 21 and 22.

In scanning exposure apparatus 10, reticle stage RST needs to be scanned at a target scanning speed four times (or five times) wafer stage WST, so that the acceleration capability of reticle stage is a limiting condition. Since it is conceivable, the following description focuses on acceleration control of reticle stage RST.

FIG. 21A shows the scanning exposure method for each of the above shots in the scanning exposure method of the present invention.
The time change of the speed command value of the reticle stage RST in the scanning direction (Y direction) when the first acceleration control method is adopted is shown. FIG. 21B shows, as a comparative example, a temporal change in the speed command value of the reticle stage RST in the scanning direction (Y direction) corresponding to FIG. 8B described above. Further, FIG. 21C shows a time change of the speed command value of the reticle stage RST in the scanning direction (Y direction) when the second acceleration control method is employed during the scanning exposure for each shot. I have. In these figures, the horizontal axis represents time, and the vertical axis represents the speed command value _Vry in the Y direction of the reticle stage.

In the following description, the acceleration time from zero to the target scanning speed Vr is Ta, the synchronization settling time between the reticle and the wafer is Ts, the exposure time is Te, and the adjustment time, ie, the constant speed overscan time is Tw. Target scanning speed V
The deceleration time from r to zero is Td.

In the first acceleration control method, FIG.
As shown in FIG. 2, instead of the constant acceleration control based on the maximum acceleration generated by the maximum thrust that can be generated by the linear motor constituting the drive system 29 in FIG. 2, the acceleration change curve whose acceleration gradually converges to zero is used. Reticle stage RS
T is accelerated in the synchronous movement direction (Y direction) from zero speed to the target scanning speed Vr. Here, a quadratic curve (parabola) or a higher-order curve is used as the acceleration change curve.

According to the first acceleration control method, at the time of scanning exposure for each shot, prior to the synchronous movement of the reticle R and the wafer W, the reticle R changes its acceleration such that its acceleration gradually converges to zero. Since acceleration is performed along the Y direction based on the curve, as shown in FIG. 21B, the acceleration is discontinuous at the end of acceleration, as in the case of accelerating to the target scanning speed Vr at a constant acceleration. That is, there is no sudden change.

FIGS. 22 (A) and 22 (B) show FIG.
(A) and (B) correspond to the settling time Ts and the time change of the position error with respect to the target position of the reticle stage RST is shown. Although the target position naturally changes with time, FIGS. 22A and 22B show a position error based on the target position (0 in the drawing) at each time point. As is apparent from a comparison between FIGS. 22A and 22B, according to the first acceleration control method described above, FIG.
It can be seen that the position error with respect to the target position can be quickly converged within the allowable range as compared with the case of 1 (B). This is because high-frequency vibration of reticle stage RST caused by the rapid change of the acceleration can be suppressed. In this case, the reticle stage RST, which is a stage whose acceleration capability is a constraint, can quickly converge to the target position, that is, the target scanning speed, and as a result, the reticle R (the reticle stage R)
It is clear that the synchronization settling time Ts between the wafer ST (ST) and the wafer W (wafer stage WST) can be shortened (see FIGS. 21A and 21B).

When the first acceleration control method is adopted, the acceleration time Ta itself tends to be longer than that in the case of acceleration at a constant acceleration.
The shortening of s more than compensates for the increase in acceleration time.
As is clear from comparison between (A) and (B), the prescan time (Ta + Ts) is shorter by Δt1 when the first acceleration control method is employed. As described above, since the synchronous settling time Ts and the constant speed overscan time Tw are set to the same time, the constant speed overscan time Tw is also shorter in FIG. 21A, and the acceleration is very easy to control. In the case as shown in FIG. 21A in which the speed changes on the side and the deceleration side are set to be symmetrical, the total total time from the start of acceleration of the reticle stage RST to the end of deceleration for one shot exposure is 2Δt1. Therefore, the throughput can be improved.

In the first acceleration control method, since the control method is very simple, the case where the speed change on the acceleration side and the speed change on the deceleration side are set symmetrically has been described. Since there is no settling time for control, there is no problem even if the acceleration is suddenly changed during deceleration.

Therefore, in the second acceleration control method, focusing on this point, as shown in FIG. 21C, only during deceleration, reticle stage RST is moved to a constant acceleration (negative acceleration) corresponding to the maximum acceleration. (Acceleration). In this case, the constant-speed overscan time Tw is longer than the case of the first acceleration control method of FIG. 21A, but the deceleration time Td is much shorter, so that the total overscan time (Tw + Td) is It can be seen that the time is shorter by the time Δt2 than in the first acceleration control method (see FIGS. 21A and 21C). Therefore,
In the scanning exposure for the shots S1, S2, and S3, the total total time from the start of the acceleration of the reticle R to the end of the deceleration can be further reduced. Here, FIG.
If the areas of the hatched portions in FIG. 21A and FIG. 21C are made equal, the reticle stage RST can be correctly stopped at the scanning start position of the next shot.

The first and second acceleration control methods described above
The same can be applied to the wafer stage side, and the first and second wafers can be applied to both the reticle stage and the wafer stage.
It is most preferable to apply the acceleration control method described above in terms of improving the throughput.

The shot S1 shown in FIG.
In the scanning direction (Y direction) when the wafer stage WST is moved along the U-shaped (or V-shaped) movement trajectory as shown in FIG. ), The first and second acceleration control
May be adopted. For example, when the first acceleration control method is employed, the wafer W is consequently moved along a path close to the shortest distance, so that the throughput can be further improved in combination with the shortening of the settling time. . Further, when the second acceleration control method is employed, the deceleration time can be further reduced, so that the throughput can be further improved.

The above first and second acceleration controls can be performed by obtaining a control amount of acceleration by a predetermined calculation based on an interferometer measurement value or the like each time scanning exposure of each shot is performed. May be prepared in advance, and the acceleration control map may be used to execute based on time.

The first and second acceleration control methods described above can be similarly applied to the exposure apparatus 110 of the second embodiment described above, and the effect of improving the throughput can be similarly obtained. Needless to say.

In the above embodiment, the case where ultraviolet light having a wavelength of 100 nm or more, specifically, a KrF excimer laser or an ArF excimer laser is used as the illumination light for exposure has been described. KrF excimer laser and the same far ultraviolet region belonging far ultraviolet such as lines (DUV) light, or be a vacuum ultraviolet (VUV) light such as ArF excimer laser and F ₂ laser belonging to the same vacuum ultraviolet region (wavelength 157 nm) it can. Note that Y
A harmonic of an AG laser may be used.

Further, a single-wavelength laser in the infrared or visible range oscillated from a DFB semiconductor laser or a fiber laser is amplified by, for example, a fiber amplifier doped with erbium (or both erbium and ytterbium) to form a nonlinear optical amplifier. It is also possible to use a harmonic whose wavelength has been converted to ultraviolet light using a crystal.

For example, the oscillation wavelength of a single-wavelength laser is set to 1.
When the wavelength is in the range of 51 to 1.59 μm, the generated wavelength is 18
An eighth harmonic having a wavelength in the range of 9 to 199 nm or a tenth harmonic having a generation wavelength in the range of 151 to 159 nm is output. In particular, the oscillation wavelength is set to 1.544 to 1.553.
If it is within the range of μm, the generated wavelength is 193 to 194 nm.
Is obtained, that is, ultraviolet light having substantially the same wavelength as that of the ArF excimer laser is obtained.
When the wavelength is in the range of 57 to 1.58 μm, the generated wavelength is 15
The tenth harmonic in the range of 7 to 158 nm, ie, F ₂
Ultraviolet light having substantially the same wavelength as the laser is obtained.

The oscillation wavelength is set to 1.03 to 1.12 μm
, A 7th harmonic whose output wavelength is in the range of 147 to 160 nm is output.
Assuming that the wavelength is within a range of 099 to 1.106 μm, the seventh harmonic having a generated wavelength within a range of 157 to 158 nm, that is, F
Ultraviolet light having almost the same wavelength as the _two lasers is obtained. Note that an ytterbium-doped fiber laser is used as the single-wavelength oscillation laser.

In the exposure apparatus of the above embodiment,
The illumination light for exposure is not limited to light having a wavelength of 100 nm or more, and light having a wavelength of less than 100 nm may be used. For example, in recent years, in order to expose a pattern of 70 nm or less, EUV (Ex) in a soft X-ray region (for example, a wavelength region of 5 to 15 nm) using a SOR or a plasma laser as a light source.
In addition to generating treme ultraviolet light, an EUV exposure apparatus using an all-reflection reduction optical system designed based on the exposure wavelength (for example, 13.5 nm) and a reflective mask is being developed. In this apparatus, a configuration in which scan exposure is performed by synchronously scanning the mask and the wafer using arc illumination can be considered, and such an apparatus is also included in the scope of the present invention.

The present invention can be applied to an exposure apparatus using a charged particle beam such as an electron beam or an ion beam. In the electron beam exposure apparatus, for example, a thermionic emission type lanthanum hexaborite (LaB ₆ ) or tantalum (Ta) can be used as an electron gun. The electron beam exposure apparatus may be any of a pencil beam system, a variable shaped beam system, a cell projection system, a blanking aperture array system, and a mask projection system.
The mask projection method uses 250 n separated from each other on the mask.
The circuit pattern is formed by disassembling the circuit pattern into a number of subfields of about m square, and the electron beam is sequentially shifted on the mask in the first direction, and is synchronized with the movement of the mask in the second direction orthogonal to the first direction. Then, the wafer is relatively moved with respect to the electron optical system for projecting the decomposition pattern in a reduced size, and a combined pattern is formed by joining reduced images of the decomposition pattern on the wafer.

In the above embodiment, the stage drive system is a magnetic levitation type linear actuator, and the chuck system is also electrostatically supposed, assuming that the chamber is evacuated by an EUV exposure apparatus or an electron beam exposure apparatus. Although a device such as a suction method is used, in a light exposure apparatus having an exposure wavelength of 100 nm or more, a vacuum may be used for a stage drive system by air flow or suction.

In the above embodiment, the case where the present invention is applied to a step-and-scan type reduction projection exposure apparatus (scanning stepper) has been described, but in a state where the reticle and the wafer are almost stationary. A step-and-repeat type reduction projection exposure apparatus (stepper) that repeats an operation of transferring a reticle pattern onto a wafer via a projection optical system, or a mirror projection aligner, a proximity type exposure apparatus (for example, X-ray irradiation) The present invention can also be applied to a scanning type X-ray exposure apparatus that moves a mask and a wafer relative to an arc-shaped illumination region to be integrated.

The projection optical system may use not only a reduction system but also an equal magnification system or an enlargement system (for example, an exposure apparatus for manufacturing a liquid crystal display). Further, the projection optical system may be any one of a refraction system, a reflection system, and a catadioptric system.
The type of glass material or coating material that can be used for an optical element (particularly, a refraction element) is limited by the wavelength of the illumination light for exposure, and the maximum diameter that can be manufactured differs for each glass material. One of the refraction system, the reflection system, and the catadioptric system is selected in consideration of the exposure wavelength to be used, its wavelength width (narrow bandwidth), the field size of the projection optical system, the numerical aperture, and the like.

In general, if the exposure wavelength is about 190 nm or more, synthetic quartz and fluorite can be used as the glass material, so that not only reflective systems and catadioptric systems but also refractive systems are relatively Can be easily adopted. In the case of vacuum ultraviolet light having a wavelength of about 200 nm or less, a refraction system can be used depending on the narrowed wavelength width. In particular, when the wavelength is about 190 nm or less, an appropriate material other than fluorite is used as a glass material. It is advantageous to employ a reflection system or a catadioptric system since there is no problem and it is difficult to narrow the wavelength band. Further, with EUV light, a plurality of sheets (for example, 3 to
A reflection system consisting of only (about six) reflection elements is employed. Note that an electron beam exposure apparatus uses an electron optical system including an electron lens and a deflector. Further, in the illumination light for exposure in the vacuum ultraviolet region, a gas (for example, nitrogen,
The optical path is filled with an inert gas such as helium), or the optical path is evacuated, and the EUV light or electron beam is evacuated.

Further, not only an exposure apparatus used for manufacturing a semiconductor element but also an exposure apparatus used for manufacturing a display including a liquid crystal display element for transferring a device pattern onto a glass plate and a thin film magnetic head. The present invention can also be applied to an exposure apparatus for transferring a device pattern onto a ceramic wafer, an exposure apparatus used for manufacturing an imaging device (such as a CCD), and the like.

Further, the present invention can be applied to an exposure apparatus for transferring a circuit pattern onto a glass substrate or a silicon wafer for producing a reticle or a mask. Here, a transmissive reticle is generally used in an exposure apparatus using DUV light, VUV light, or the like, and quartz glass, fluorine-doped quartz glass, fluorite,
Alternatively, quartz or the like is used. In the EUV exposure apparatus, a reflection type mask is used, and a proximity type X
In a line exposure apparatus or an electron beam exposure apparatus of a mask projection system, a transmission type mask (stencil mask, membrane mask) is used, and a silicon substrate or the like is used as a mask substrate.

The stage apparatus according to the present invention is applicable not only to the lithography apparatus used in the manufacturing process of microdevices such as semiconductor elements, such as the above-described exposure apparatus, but also to, for example, laser repair apparatuses and inspection apparatuses. Applicable. Further, the present invention can be applied to devices other than various devices used in the micro device manufacturing process.

In the semiconductor device, a step of designing the function and performance of the device, a step of manufacturing a reticle based on the design step, a step of manufacturing a wafer from a silicon material, and a step of manufacturing a reticle by the exposure apparatus of the above-described embodiment. Transferring the pattern to the wafer,
It is manufactured through a device assembly step (including a dicing step, a bonding step, and a package step), an inspection step, and the like.

[0376]

As described above, the exposure apparatus and the scanning exposure method according to the present invention have an excellent effect that the throughput can be improved.

Further, according to the stage device of the present invention, the control load can be reduced, and the position controllability of each first movable body (substrate stage) holding the substrate can be maintained at a high level. is there.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a scanning exposure apparatus according to a first embodiment.

FIG. 2 is a view schematically showing an internal configuration of the scanning exposure apparatus of FIG.

FIG. 3 is a diagram for explaining the laser interferometer system of FIG. 2 in more detail, where (A) shows interferometer beams from three interferometers constituting the laser interferometer system together with a substrate table TB. FIG. 3B is a plan view showing the interferometer beam from the second interferometer in more detail together with some optical systems constituting the interferometer, and FIG. RIY ₁ (or RIY ₂ ) and measuring beam RI
It is a diagram for explaining the positional relationship between Y _3.

FIG. 4 is a diagram schematically showing a configuration of an aerial image detector mounted on a substrate table and a configuration of a signal processing system related thereto.

5A and 5B are views for explaining the role of the movable surface plate and a control method thereof, wherein FIG. 5A is a schematic plan view near the surface plate, and FIG. 5B is viewed from the direction of arrow A in FIG. It is a schematic front view.

FIG. 6 is a diagram for explaining a reaction actuator and a reaction frame.

FIG. 7A shows a slit-shaped illumination area and a shot area S1 on a wafer inscribed in an effective field of the projection optical system.
(B) is a diagram showing the relationship between the stage moving time and the stage speed, and (C) is a wafer peripheral shot S when exposing a shot area S around the wafer.
FIG. 6 is a diagram for explaining the relationship between the moving mirror length extension and the moving mirror length extension.

FIG. 8A is a diagram showing a locus of the center P of the on-wafer illumination slit ST passing through each shot when the shots S1, S2, and S3 are sequentially exposed, and FIG. FIG. 3C is a diagram illustrating a relationship between the speed and time in the scanning direction of the wafer stage, and FIG.

FIG. 9 is a plan view near the movable platen when the wafer stage is located at a loading position for replacing a wafer W.

FIG. 10 is a plan view of the vicinity of a movable surface plate showing a state of movement of a wafer stage at the time of alignment measurement.

FIG. 11 is a plan view of the vicinity of the movable platen when the wafer stage is located at the position at the start of exposure.

FIG. 12 is a plan view showing the vicinity of a movable platen when a wafer stage is located at a position at the time of completion of exposure.

FIG. 13 is a diagram for explaining the effect of the present embodiment, and the wafer stage of the present embodiment can be used even if a moving mirror distance is deteriorated due to interferometer multi-axis and pre-scan and over-scan. It is a figure showing that it can be made small compared with the conventional square shape stage.

14A is a diagram illustrating an example in which the projection optical system is a catadioptric optical system, and FIG. 14B is a diagram illustrating another example in which the projection optical system is a catadioptric optical system.

FIG. 15 is a diagram illustrating a schematic configuration of an exposure apparatus according to a second embodiment.

FIG. 16 is a perspective view showing a positional relationship among two wafer stages, a reticle stage, a projection optical system, and an alignment system.

17 is a schematic plan view showing the vicinity of a surface plate in the apparatus of FIG.

FIG. 18 shows a wafer exchange using two wafer stages.
FIG. 4 is a plan view showing a state where an alignment sequence and an exposure sequence are being performed.

19 is a diagram showing a state in which switching between the wafer exchange / alignment sequence and the exposure sequence in FIG. 18 has been performed.

FIG. 20 is a schematic plan view showing a modification of the second embodiment.

21A is a diagram showing a time change of a speed command value in the scanning direction of the reticle stage when the first acceleration control method is adopted, and FIG. 21B is a reticle stage corresponding to FIG. (C) is a diagram showing a time change of the speed command value of the reticle stage in the scanning direction when the second acceleration control method is adopted.

FIGS. 22A and 22B are diagrams showing the time change of the position error with respect to the target position of the reticle stage near the settling time Ts corresponding to FIGS. 21A and 21B, respectively.

[Explanation of symbols]

10: scanning exposure apparatus (exposure apparatus), 33: reticle stage controller (part of stage control system), 42
a, 42b: planar magnetic levitation linear actuator (drive unit), 44: planar magnetic levitation linear actuator (second drive unit), 66: synchronous control system (part of stage control system), 78: wafer stage controller (Part of stage control system), 80: synchronous control system (part of stage control system), 101: stage apparatus, 110: exposure apparatus, 138: movable surface plate (second movable body), W: wafer ( Substrate, sensitive substrate), R ... reticle (mask), WST
... Wafer stage (substrate stage), WST1, WST
2 wafer stage (first movable body), RST reticle stage (mask stage), S1 shot (first partitioned area, one partitioned area), S2 shot (second partitioned area, another partitioned area).

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F046 AA11 BA04 BA05 CA04 CB01 CB02 CB05 CB08 CB13 CB22 CB23 CB25 CC01 CC02 CC03 CC06 CC13 CC16 CC18 CD04 CD06 DA01 DA02 DA05 DA13 DA14 DA27 DB01 DB05 DC02 DC10 DD01 DD03 DD06 EB01 EB01 FA03 FA05 FA06 FC05 FC08

Claims (81)

[Claims] 1. An exposure apparatus for sequentially transferring a pattern of the mask to a plurality of shot areas on the sensitive substrate by synchronously moving a mask and a sensitive substrate, wherein the two-dimensional mask is held while holding the sensitive substrate. A substrate stage that moves in a plane; a mask stage that is movable while holding the mask; a run-up operation for the next shot exposure after the substrate stage has been exposed, and a non-scanning direction for the next shot exposure. A stage control system for controlling the two stages so that the stepping operation is performed simultaneously and in parallel, and the stepping operation in the non-scanning direction is completed before the synchronization adjustment period of the two stages before the next shot exposure. An exposure apparatus comprising: 2. The stage control system according to claim 1, wherein the acceleration of the substrate stage in a non-scanning direction corresponding to an overscan consisting of a constant speed movement time and a deceleration time of the mask stage after a previous shot exposure is performed in a next shot exposure. 2. The exposure according to claim 1, wherein the two stages are controlled so that an absolute value is larger than a deceleration in a non-scanning direction of the substrate stage in a portion corresponding to a pre-scan of the mask stage before starting. apparatus. 3. A scanning exposure method for sequentially transferring a mask pattern to a plurality of partitioned areas on a substrate, wherein the mask and the substrate are synchronously moved to scan and expose one of the plurality of partitioned areas. In order to scan and expose another partitioned area adjacent to the one partitioned area in a second direction orthogonal to a first direction in which the substrate is synchronously moved, the substrate after the scanning exposure of the one partitioned area is finished. A scanning exposure method comprising: starting acceleration of the substrate in the first direction before the stepping operation in the second direction ends. 4. The apparatus according to claim 1, wherein the substrate is moved obliquely with respect to the first and second directions by the acceleration before the scanning exposure of the another divided area, and the moving speed of the substrate in the first direction is higher than that of the substrate. 4. The scanning exposure method according to claim 3, wherein the speed is set according to the sensitivity characteristic. 5. After the scanning exposure of the one partitioned area is completed, the substrate is moved in the first direction until the substrate is separated in the first direction by a running distance necessary for scanning and exposing the another partitioned area. 5. The scanning exposure method according to claim 3, wherein the moving is performed in the second direction while decelerating. 6. The substrate according to claim 1, wherein the first exposure is performed between the scanning exposure of the one divided area and the scanning exposure of the another divided area.
The scanning exposure method according to claim 3, wherein at least one of the speed component in the direction and the speed component in the second direction is moved so as not to be zero. 7. The method according to claim 1, wherein the substrate is provided between the scanning exposure of the one partitioned area and the scanning exposure of the another partitioned area.
The position in the second direction where the moving speed in the direction becomes zero is 1
The scanning exposure method according to any one of claims 3 to 6, wherein the scanning exposure method is moved so as to be closer to the another divided area than one divided area. 8. A first partition area and a second partition on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged in a second direction substantially orthogonal to the first direction in which the substrate is synchronously moved. In the method of scanning and exposing each area with the pattern of the mask, the first exposure of the substrate is performed after the completion of the scanning exposure of the first partitioned area.
Moving the substrate in the second direction while decelerating the substrate until the moving speed in the second direction becomes zero, and accelerating the substrate in the first direction before scanning exposure of the second partitioned area. A scanning exposure method characterized by moving in a direction. 9. The method according to claim 1, wherein a position in the second direction of the substrate at which the moving speed in the first direction becomes zero is set between both ends of the second partitioned area in the second direction. Item 9. The scanning exposure method according to Item 8. 10. A first partition area and a second partition area on the substrate, which are arranged in a second direction substantially orthogonal to a first direction in which the mask and the substrate are synchronously moved. In the scanning exposure method of transferring the pattern of the mask, the substrate is moved so that its movement trajectory is substantially parabolic after the scanning exposure of the first section area, and then the second section is moved by the pattern of the mask. A scanning exposure method comprising scanning and exposing an area. 11. The scanning exposure according to claim 10, wherein a position of the substrate at the vertex of the parabola in the second direction is set closer to the second section area than the first section area. Method. 12. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged in a second direction substantially orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method of transferring the pattern of the mask respectively, during the deceleration of the substrate after the scanning exposure of the first partitioned area, and during the acceleration of the substrate before the scanning exposure of the second partitioned area, A scanning exposure method comprising: moving a substrate in a direction intersecting the first and second directions. 13. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method of sequentially transferring the pattern of the mask, the position of the substrate in the second direction coincides with the position of the second divided region in the second direction after the scanning exposure of the first divided region is completed. Scanning acceleration of the substrate for scanning exposure of the second partitioned area before starting. 14. After the scanning exposure of the first partitioned area is completed,
The substrate moves obliquely to the first direction before the velocity component of the substrate in the first direction becomes zero, and immediately after the acceleration of the substrate starts, the velocity in the first and second directions increases. 14. The scanning exposure method according to claim 13, wherein the substrate is moved so that the component does not become zero. 15. A first partition area and a second partition area on the substrate, wherein the mask and the substrate are synchronously moved, and the substrate is arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method of sequentially transferring the pattern of the mask, the scanning of the second partitioned area before the velocity component of the substrate in the second direction after the scanning exposure of the first partitioned area becomes zero is completed. A scanning exposure method, wherein acceleration of the substrate for exposure is started. 16. The scanning exposure direction according to claim 14, wherein the substrate is accelerated in the first direction and decelerated in the second direction. 17. The acceleration of the substrate in the second direction is started before the velocity component of the substrate in the first direction becomes zero after the scanning exposure of the first partitioned area is completed. 17. The scanning exposure method according to claim 15, wherein 18. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged in a second direction orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method of sequentially transferring the pattern of the mask, the position of the substrate in the second direction at which the velocity component in the first direction of the substrate becomes zero after the completion of the scanning exposure of the first partitioned area, Positioning the substrate obliquely with respect to the first and second directions in order to scan and expose the second divided region with respect to the first divided region with respect to the position of the second divided region in the second direction. A scanning exposure method characterized by moving. 19. A first partition area and a second partition area on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. And in the scanning exposure method of sequentially transferring the pattern of the mask, in order to move the substrate in the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area in the opposite direction,
After completion of the first scanning exposure, the speed component of the substrate in the first direction is set to zero, and the substrate is moved so that the speed components in the first and second directions do not become zero prior to the second scanning exposure. A scanning exposure method characterized by accelerating. 20. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. A scanning exposure method for sequentially transferring the pattern of the mask between the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area, The position of the substrate in the second direction where the velocity component in one direction becomes zero is between the position of the first partitioned area in the second direction and the location of the second partitioned area in the second direction. Scanning exposure method, wherein the substrate is moved as described above. 21. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged in a second direction orthogonal to the first direction in which the substrate is synchronously moved. Wherein the movement trajectory of the substrate between the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area is substantially parabolic. Moving the substrate without reducing the velocity component in the second direction to zero during deceleration of the substrate after the first scanning exposure and during acceleration of the substrate before the second scanning exposure. A scanning exposure method. 22. The apparatus according to claim 21, wherein the velocity component of the substrate in the second direction is substantially zero immediately after the end of the first scanning exposure and immediately before the start of the second scanning exposure.
3. The scanning exposure method according to 1. 23. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved. Wherein the pattern of the mask is sequentially transferred to the substrate after the first scanning exposure between the first scanning exposure of the first partitioned area and the second scanning exposure of the second partitioned area. Before the velocity component in the first direction becomes zero, the acceleration of the substrate in the second direction is started, and before the velocity component in the second direction of the substrate becomes zero, A scanning exposure method, characterized by starting acceleration in the first direction. 24. The acceleration of the substrate in the first direction,
The scanning exposure method according to claim 23, wherein the method is started during deceleration of the substrate in the second direction. 25. The acceleration of the substrate in the second direction,
25. The scanning exposure method according to claim 23, wherein the method is started during deceleration of the substrate after the first scanning exposure. 26. When the substrate is moved in the second direction between the scanning exposure of the first sectioned area and the scanning exposure of the second sectioned area, the acceleration of the substrate is accelerated and decelerated during the deceleration. Wherein the absolute value of is different.
26. The scanning exposure method according to claim 25. 27. A mask and a substrate are synchronously moved, and the substrate is arranged in first and second partition regions on the substrate arranged in a second direction substantially orthogonal to a first direction in which the substrate is synchronously moved. In a scanning exposure method for transferring a pattern of a mask, when the substrate is moved in the second direction between a first scanning exposure of the first partitioned region and a second scanning exposure of the second partitioned region, A scanning exposure method, wherein the absolute value of the acceleration differs between the time of acceleration and the time of deceleration of the substrate. 28. After the first scanning exposure, the first
Starting acceleration of the substrate in the second direction during deceleration in the direction, and starting deceleration of the substrate in the second direction during acceleration in the first direction before the second scanning exposure. The scanning exposure method according to claim 27, wherein 29. The scanning exposure method according to claim 27, wherein the substrate is moved without stopping between the first scanning exposure and the second scanning exposure. 30. The scanning exposure method according to claim 29, wherein acceleration and deceleration of the substrate in the second direction is started before and after the velocity component in the first direction becomes zero. 31. The scanning exposure method according to claim 26, wherein the absolute value of the acceleration in the second direction is made larger during acceleration of the substrate than during deceleration. 32. The apparatus according to claim 8, wherein the substrate is moved without stopping between the scanning exposure of the first partitioned area and the scanning exposure of the second partitioned area. The scanning exposure method according to claim 1. 33. The method according to claim 8, wherein the velocity component of the substrate in the second direction is made substantially zero before the synchronous setting of the mask and the substrate prior to the scanning exposure of the second partitioned area. 33. The scanning exposure method according to any one of Items 1 to 32. 34. The mask is reciprocated by scanning exposure of the first partitioned area and scanning exposure of the second partitioned area in which the substrate is moved in the reverse direction along the first direction. The scanning exposure method according to any one of claims 10 to 33, characterized in that: 35. The substrate has its velocity component simultaneously reduced to zero in both the first and second directions until scanning exposure of all the divided areas on the substrate to which the pattern of the mask is to be transferred is completed. The scanning exposure method according to any one of claims 10 to 34, wherein the scanning exposure method is moved so as not to be shifted. 36. A step-and-step in which a mask and the substrate are synchronously moved for each divided area on the substrate and the pattern of the mask is sequentially transferred to a plurality of divided areas on the substrate.
In a scanning exposure method of a scanning method, the substrate is moved without stopping between scanning exposures of two divided areas on the substrate to which a pattern of the mask is transferred by reciprocating movement of the mask. Exposure method. 37. The substrate is moved in a first direction in which the substrate is synchronously moved and a second direction orthogonal to the first direction until scanning exposure of the last partitioned area on the substrate to which the pattern of the mask is to be transferred is completed. 37. The scanning exposure method according to claim 36, wherein the moving is performed such that at least one speed component in the direction does not become zero. 38. The mask according to claim 3, wherein acceleration of the mask is started before the velocity component of the substrate in the second direction becomes zero during the scanning exposure. The scanning exposure method according to the above. 39. An acceleration change curve such that the acceleration of the substrate gradually converges to zero during at least one of acceleration of the substrate before the scanning exposure and deceleration of the substrate after the scanning exposure. The scanning exposure method according to any one of claims 3 to 38, wherein the scanning exposure method moves in the first direction according to the following. 40. An acceleration change curve such that the acceleration of the mask gradually converges to zero at least one of when the mask is accelerated before the scanning exposure and when the mask is decelerated after the scanning exposure. The scanning exposure method according to any one of claims 3 to 39, wherein the scanning exposure method moves in accordance with the following. 41. The scanning exposure method according to claim 39, wherein the substrate or the mask is moved according to the acceleration change curve when the substrate or the mask is accelerated. 42. The scanning exposure method according to claim 41, wherein the substrate or the mask is decelerated at a constant acceleration when the substrate or the mask is decelerated. 43. A scanning exposure method in which a mask and a substrate are synchronously moved and a pattern of the mask is transferred to one or more divided regions on the substrate. Prior to synchronous movement between the mask and the substrate, at least one of the mask and the substrate is accelerated along the synchronous movement direction based on an acceleration change curve whose acceleration gradually converges to zero. Scanning exposure method. 44. A first substrate on the substrate arranged along a second direction orthogonal to the first direction in which the substrate is synchronously moved.
When sequentially transferring the pattern of the mask to the divided area and the second divided area, during the deceleration of the substrate in the first direction after the scanning exposure of the first divided area and before the scanning exposure of the second divided area During acceleration of the substrate in a first direction, the substrate is moved to the first and second directions.
The scanning exposure method according to claim 43, wherein the scanning exposure method moves in a direction intersecting the direction. 45. A first partition region and a second partition region on the substrate, the mask and the substrate being synchronously moved, and the substrate being arranged in a second direction orthogonal to the first direction in which the substrate is synchronously moved. In the scanning exposure method of sequentially transferring the pattern of the mask, at least during the scanning exposure of the first partitioned region, at least one of the mask and the substrate is accelerated prior to the synchronous movement of the mask and the substrate. Is accelerated along the first direction based on an acceleration change curve such that the velocity gradually converges to zero, and decelerates along the first direction at a constant deceleration after the end of the synchronous movement. Scanning exposure method. 46. The method according to claim 46, wherein the substrate is decelerated in the first direction after the scanning exposure of the first partitioned area is completed, and the substrate is accelerated in the first direction before the scanning exposure of the second partitioned area. The scanning exposure method according to claim 45, wherein the scanning exposure method moves in a direction intersecting the first and second directions. 47. A first direction in which the substrate is synchronously moved,
The position of the substrate is controlled using a first length measuring beam in a direction different from the second direction, at least in a second direction among second directions orthogonal to the second direction. 47. The scanning exposure method according to any one of the items 46. 48. The scanning exposure method according to claim 47, wherein the position of the substrate in the first direction is controlled using a second length measuring beam substantially parallel to the first direction. 49. The position control of the substrate is performed by using a third length measuring beam that intersects the first and second directions and is different from the first length measuring beam. 49. The scanning exposure method according to 47 or 48. 50. a surface plate; at least two first movable bodies movable relative to the surface plate and respectively holding substrates; each of the first movable bodies being arranged on an upper part thereof; A second movable body disposed on the surface plate and relatively moving with respect to each of the surface plate and each of the first movable bodies; and a second movable body provided on the second movable body, A stage device comprising: a driving device that drives in a two-dimensional plane; and wherein the second movable body is configured to move in response to a reaction force when the first movable bodies are driven. . 51. The mass of each of the first movable bodies is substantially 1/9 or less of the mass of the second movable bodies, and the second movable body drives the second movable bodies at a low response frequency on the surface plate. The driving device is further provided.
The stage device according to 0. 52. An exposure apparatus for transferring a pattern of a mask onto a substrate, comprising: the stage device according to claim 50, wherein the substrate onto which the pattern of the mask is transferred constitutes the stage device. An exposure apparatus characterized by being held by each first movable body. 53. A projection optical system for projecting the pattern of the mask onto the substrate, wherein the driving device constituting the stage device includes a pattern of the mask on a substrate held by each of the first movable bodies. 53. The method according to claim 52, wherein, when transferring the image, the first movable body that holds the substrate on which the pattern is to be transferred is driven in a scanning direction with respect to the projection optical system in synchronization with the mask. Exposure equipment. 54. An exposure apparatus for transferring a pattern of a mask to each of a first and a second divided region arranged adjacent to each other on a substrate, the substrate stage holding the substrate; and the first divided region. A first driving device that, when the substrate stage is moved between the first exposure to the first exposure and the second exposure to the second partitioned area, makes the absolute value of the acceleration different between the time of acceleration and the time of deceleration of the substrate stage An exposure apparatus comprising: 55. The exposure apparatus according to claim 54, wherein the first driving device makes the absolute value of the acceleration larger during the acceleration than during the deceleration. 56. A first platen on which the substrate stage is disposed; and a second platen on which the first platen is disposed, wherein the first platen is responsive to movement of the substrate stage. 56. The exposure apparatus according to claim 54, wherein the surface plate is configured to move relative to the substrate stage on the second surface plate. 57. A semiconductor device further comprising a second substrate stage disposed on the first surface plate, wherein the first surface plate is moved so as to cancel out a resultant force of reaction forces generated by the movement of the two substrate stages. 57. The exposure apparatus according to claim 56, wherein: 58. The apparatus further comprising a second substrate stage disposed on the first surface plate, wherein the first surface plate prevents a change in a center of gravity position caused by movement of at least one of the two substrate stages. The exposure apparatus according to claim 56, wherein the exposure apparatus is moved. 59. A second driving device for moving the first surface plate relative to the second surface plate; and controlling a control response of the second driving device by a plurality of operations including an exposure operation of the substrate. The exposure apparatus according to any one of claims 56 to 58, further comprising: a control unit configured to be variable. 60. The control device according to claim 26, wherein the control is such that the first platen substantially maintains a position with respect to the second platen when the substrate stage is moved between the first and second exposures. 60. The exposure apparatus according to claim 59, wherein a control response of the second driving device is set to be as follows. 61. The first driving device moves the substrate stage such that a plurality of partitioned areas on the substrate are exposed by a step-and-repeat method or a step-and-scan method. Claim 54
61. The exposure apparatus according to any one of claims 60. 62. The apparatus according to claim 54, wherein the first driving device includes a first planar magnetic levitation linear actuator that drives the substrate stage with at least three degrees of freedom. Exposure apparatus according to the above. 63. The apparatus according to claim 59, wherein the second driving device has a second planar magnetic levitation linear actuator that moves the first surface plate relative to the second surface plate. The exposure apparatus according to any one of the above. 64. An exposure apparatus for transferring a pattern of a mask onto a substrate, comprising: a first platen; a plurality of substrate stages respectively arranged on the first platen and each holding the substrate; 1
A second platen on which a platen is disposed; and a first platen relatively movable with respect to the second platen so as to suppress a change in the center of gravity due to movement of at least one of the plurality of substrate stages. An exposure apparatus comprising: a supporting device that supports the device. 65. A first substrate stage of the plurality of substrate stages is moved so that the substrate is exposed by a step-and-repeat method or a step-and-scan method, and the supporting device is configured to be a first substrate stage. 65. The exposure apparatus according to claim 64, further comprising a planar magnetic levitation linear actuator that supports the surface plate so as to be relatively movable with respect to the second surface plate. 66. During the exposure operation of the substrate on the first substrate stage, a second substrate stage different from the first substrate stage is driven such that operations other than the exposure operation are performed. The exposure apparatus according to claim 65, wherein: 67. An apparatus according to claim 67, further comprising an alignment system for detecting a mark on said substrate, wherein said second substrate stage executes mark detection by said alignment system or loading or unloading of said substrate. The exposure apparatus according to claim 66. 68. The substrate stage has first and second reflecting surfaces arranged so that extending directions thereof intersect at an acute angle with each other, and length measurement axes orthogonal to the first and second reflecting surfaces, respectively. The exposure apparatus according to any one of claims 54 to 67, further comprising first and second interferometers having the following. 69. The first and second reflecting surfaces are arranged such that a trapezoid having both reflecting surfaces on two sides other than an upper bottom and a lower bottom includes the substrate. 68
3. The exposure apparatus according to claim 1. 70. The first and second reflection surfaces each having a triangular shape substantially including the substrate on the substrate stage.
70. The exposure apparatus according to claim 68, wherein the exposure apparatus is formed along a side. 71. A length of the first reflecting surface or the second reflecting surface in an extending direction thereof is set substantially longer than an exposure range on the substrate. 70. The exposure apparatus according to any one of -70. 72. The exposure apparatus according to claim 71, wherein the exposure range includes all partial regions where the pattern of the mask is to be transferred on the substrate. 73. A mask stage for holding the mask; and a driving device for synchronously moving the mask stage and the substrate stage in a first direction to transfer a pattern of the mask onto the substrate, 68. The substrate stage according to any one of claims 54 to 67, wherein the substrate stage has a first length measurement reference plane extending along a direction intersecting at an acute angle with the synchronized first direction. Exposure equipment. 74. The method according to claim 73, wherein the first reference plane for length measurement is formed over substantially the entire moving range of the substrate stage in the scanning exposure operation of the substrate with respect to its extending direction. 3. The exposure apparatus according to claim 1. 75. The first reference plane for length measurement, wherein the length in the extending direction thereof is set substantially longer than the exposure range on the substrate.
3. The exposure apparatus according to claim 1. 76. The exposure apparatus according to claim 75, wherein the exposure range includes all the divided areas where the pattern of the mask is to be transferred on the substrate. 77. The apparatus further comprises a first interferometer having a length measurement axis orthogonal to the first length measurement reference plane, wherein a measurement value of the first interferometer is in the first direction and orthogonal to the first direction. The exposure apparatus according to any one of claims 73 to 76, wherein the exposure apparatus is used for position control of the substrate stage in at least the second direction among the second directions. 78. The exposure according to claim 73, wherein the substrate stage has a second reference plane for length measurement extending in a second direction orthogonal to the first direction. apparatus. 79. The apparatus according to claim 79, further comprising a second interferometer having a length measurement axis orthogonal to the second length measurement reference plane, wherein a measurement value of the second interferometer is a value of the substrate stage with respect to the first direction. The exposure apparatus according to claim 78, wherein the exposure apparatus is used for position control. 80. The substrate stage, wherein the first stage comprises:
And a third reference plane for length measurement that intersects both the second direction perpendicular to the first reference plane and a direction different from the first reference plane for length measurement. Exposure apparatus according to Item. 81. The apparatus further comprises a third interferometer having a length measuring axis orthogonal to the third length measuring reference plane, wherein the measured value of the third interferometer is at least in the first and second directions. The exposure apparatus according to claim 80, wherein the exposure apparatus is used for position control of the substrate stage with respect to one side.