JP2000077503A - Stage device and aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a base which supports a stage from being vibrated caused by the difference between reactions resulting from the movement of the stage and the compensating forces of the reactions. SOLUTION: Linear motors 40A and 40B, respectively composed of movers 36A and 36B and integrally attached to a stage RST, and stators 38A and 38B which are supported by a supporting member 58, in such a way that the stators 38A and 38B can move relative to the movers 36A and 36B in the X-axis direction integrally with the stage RST, and, at the same time, the stators 38A and 38B can move in the X-axis direction with respect to a base, are used as the drive devices for the stage RST. When the stage RST is moved by means of the motors 40A and 40B, although the reactions of the drive forces act on the stators 38A and 38B, since the stators 38A and 38B are supported by the support member 58 in such a state that the stators 38A and 38B is movable in the X-axis direction with respect to the base, the reactions are not transmitted to the base. Therefore, the base can be prevented from being vibrated by reactions when the state RST is driven.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage apparatus and an exposure apparatus, and more particularly, to an exposure apparatus used in a lithography process for manufacturing a semiconductor element, a liquid crystal display element, and the like, and can be suitably applied to the exposure apparatus. It relates to a stage device.

[0002]

2. Description of the Related Art Conventionally, in a lithography process for manufacturing a semiconductor device, a liquid crystal display device, etc., a step-and-repeat type reduction projection exposure apparatus (a so-called stepper) or a step-and-scan type scan type reduction. Light exposure apparatuses such as projection exposure apparatuses (so-called scanning steppers) are mainly used. In addition, an electron beam exposure apparatus (hereinafter, referred to as an “EB exposure apparatus”) is also used.

In these exposure apparatuses, in order to transfer a pattern of a mask or a reticle (hereinafter, collectively referred to as a “reticle”) onto a plurality of shot areas on a wafer as a substrate, a projection optical system such as a projection lens or an electromagnetic lens is used. A system and a positioning stage called a wafer stage for positioning the wafer at a projection position (exposure position) of the projection optical system are used. The projection optical system is fixed to the main body column, and the wafer stage moves on this main body column.

For example, in the case of a light exposure apparatus such as a stepper,
The first column that holds the projection optical system (part of the main body column)
A stage base made of rectangular granite is fixed on the upper surface of a hanging base (part of the main body column) suspended below the wafer base, and the wafer stage moves two-dimensionally on this stage base. In some cases, the stage base is suspended directly from the first column.

In this case, the reaction force generated when the wafer stage is accelerated or decelerated acts on the heavy stage base, and as a result, the main body column vibrates or swings, and the positioning performance and exposure accuracy (overlay accuracy) of the wafer stage are reduced. Sometimes it was worse.

In the case of a scanning stepper, a scanning exposure method is employed in which the entire surface of a reticle pattern is transferred onto a wafer by synchronously moving the reticle and the wafer in the scanning direction. The reticle stage for holding the reticle also moves on the main body column.

For this reason, a reaction force generated when the wafer stage and the reticle stage are accelerated or decelerated acts on the main body column, and the main body column vibrates or swings, thereby deteriorating the position control performance of the stage and the exposure accuracy. was there.

Conventionally, in order to suppress such vibration of the main body column, a compensating force generating mechanism for applying a reverse compensating force for canceling the reaction force to the stage base or another part of the main body column. (Also called a reaction mechanism or a reaction force canceller).

[0009]

The conventional compensating force generating mechanism calculates a reaction force generated by the movement of the stage and calculates a reaction force equal in magnitude to the reaction force and in the opposite direction to the main body column as a compensation force. Had become. This is because, when an acceleration sensor or the like is provided in the main body column and the vibration of the main body column is feedback-controlled based on the output of the acceleration sensor, a control delay always occurs and the vibration of the main body column is effectively suppressed. This is to prevent the control delay from being caused by giving the compensation force calculated by feed forward.

However, since the reaction force actually generated by the movement of the stage does not match the value obtained by the calculation, the reaction force does not match the compensation force generated by the compensation force generation mechanism, and an error between the two. Caused the main body column to vibrate.

As a driving source for a stage of an exposure apparatus in recent years, a linear motor capable of driving at a higher speed is often used instead of the conventional combination of a feed screw and a rotary motor from the viewpoint of improving throughput. It has become In the case of such a stage driven by a linear motor, an error occurs between the reaction force acting on the main body column and the compensating force when the stage is actually driven due to the following reasons. Had become.

That is, in the linear motor, since the metal plate containing the coil moves across the magnetic field, an eddy current is generated in the metal plate, thereby generating a viscous resistance which is a force that hinders the movement. This force is proportional to the speed of movement. In addition, when a current flows through the coil, a back electromotive force is generated in the coil, and this back electromotive force also acts as a force that hinders movement of the metal plate (coil). In addition, an eddy current is generated in the metal plate due to a change in the current flowing through the coil, and the eddy current becomes a force that hinders movement of the metal plate. A thrust error occurs due to the force that hinders such movement, and as a result, an error occurs between the reaction force and the compensation force accompanying the movement of the stage.

The present invention has been made under such circumstances, and a first object of the present invention is to provide a base (stage) for supporting a stage due to an error between a reaction force accompanying the movement of the stage and this compensation force. The present invention is to provide a stage device capable of preventing generation of vibration on the base).

A second object of the present invention is to improve exposure accuracy by suppressing vibration of a main body column holding a projection optical system due to a driving reaction force of a mask stage during scanning exposure. It is an object of the present invention to provide an exposure apparatus capable of performing the above-described steps.

A third object of the present invention is to provide an exposure apparatus capable of improving throughput and overlay accuracy.

[0016]

A first stage device according to the present invention comprises a stage (RST) movable with respect to a base (30) and a driving device (4) for driving the stage.
0), the driving device is a movable element (3) integrally attached to the stage.
6A, 36B) and a stator (38A, 38B) supported by a support member (58) to move the mover integrally with the stage in a predetermined direction and to be movable in the predetermined direction with respect to the base. ), And a biasing device (49A, which applies force to both ends of the stator in the predetermined direction).
49B, 49C, and 49D).

According to this, the driving device is capable of moving the movable element integrally with the stage relative to the base in a predetermined direction and moving the movable element relative to the base in a predetermined direction. And a stator supported by the support member. Therefore, when the movable element is driven relative to the stage integrally with the stage by the stator, the reaction force acts on the stator, but the stator can be moved in the predetermined direction with respect to the base by the support member. The reaction force is not transmitted to the base. Therefore, it is possible to prevent the base from vibrating due to the reaction force when the stage is driven (during acceleration / deceleration).

Further, by applying a force (compensation force) to both ends of the stator in a predetermined direction by the biasing device, the relative movement of the stator with respect to the base can be suppressed or prevented. Even if an error occurs between the reaction force and the compensation force, the error force is not transmitted to the base, and the base does not vibrate.

In this case, the stator (38A,
38B) a position detector (56) for detecting the position in the predetermined direction, and control for servo-controlling the biasing device based on position information from the position detector so that the stator is at a fixed position. A system (80) may be further provided.
In such a case, even if an error occurs between the reaction force (approximately equal to the stage drive thrust) acting on the stator and the compensating force due to the stage driving, the amount can be compensated. The compensating force can be made the same.

Further, the second stage device according to the present invention comprises a stage (RS) movable with respect to the base (30).
T) and a driving device (40) for driving the stage, wherein the driving device is a mover (36A, 36B) integrally attached to the stage.
And a stator (38A, 38B) that relatively drives the mover in a predetermined direction integrally with the stage, and one end of the stator in the predetermined direction is connected and disposed along the vertical direction. A first vertical member (48), a second vertical member (50) connected to the other end of the stator in the predetermined direction and disposed along the vertical direction, the first vertical member and the second vertical member. At least a connecting member (60) for connecting the member and the member,
A frame (58) for supporting the stator movably in the predetermined direction with respect to the base is provided.

According to this, the stator constituting the driving device is supported by the frame so as to be movable in a predetermined direction with respect to the base. For this reason, when the mover is driven relative to the stage integrally with the stage by the stator, the reaction force acts on the stator, but the stator can be moved in the predetermined direction with respect to the base by the frame. Because it is supported, the reaction force is not transmitted to the base. Therefore, it is possible to prevent the base from vibrating due to the reaction force when the stage is driven (during acceleration / deceleration).

Also, a frame (58) is connected to one end of the stator in a predetermined direction, and is arranged along a vertical direction.
A vertical member (48) and a second vertical member (50) connected to the other end of the stator in a predetermined direction and arranged along the vertical direction.
And a connecting member (60) for connecting the first vertical member and the second vertical member. That is, the rigidity can be improved because the frame has a gate shape, a mouth shape, an H shape, or the like.

In this case, a compensating force generating mechanism is provided between the stator and at least one of the first and second vertical members for generating a compensating force for substantially canceling a reaction force generated when the stage is driven by the driving device. May be. In this compensation force generating mechanism, when the stator includes at least two reaction actuators (49A, 49B, 49C, and 49D) provided between the stator and the first and second vertical members, respectively, A control device (80) for controlling the reaction actuator according to the direction and magnitude of the received reaction force may be further provided. In such cases,
In the control device, depending on the direction and magnitude of the reaction force received by the stator, for example, the reaction actuator is selectively controlled so that a tensile force always acts on the stator, or the reaction actuator is selected. In addition, it is possible to control both reaction actuators so that the compensation force generated by both reaction actuators is substantially the same as and opposite to the reaction force.

In the above, the first vertical member and the second vertical member may have different frequency characteristics. In such a case, since the first vertical member and the second vertical member are connected by the connecting member, the frequency characteristics in a low frequency range can be improved.

A first exposure apparatus according to the present invention is an exposure apparatus for synchronously moving a mask (R) and a substrate (W) to transfer a pattern of the mask onto the substrate via a projection optical system (PL). Wherein the base (30) is provided with the first stage device or the second stage device according to the present invention, and the base (30) is a part of a main body column (14) holding the projection optical system (PL). Wherein the stage is a mask stage (RST) for holding the mask.

According to this configuration, the base, ie, the base,
That is, the main body column holding the projection optical system can be reliably prevented from vibrating. Therefore, when the pattern of the mask is transferred to the substrate via the projection optical system by synchronously moving the mask and the substrate, that is, the vibration of the main body column caused by the driving reaction force of the mask stage during scanning exposure is suppressed. Thus, the exposure accuracy can be improved. In the case of a scanning type exposure apparatus such as a scanning stepper, the stage on the substrate side also moves, but since the driving speed of the stage on the substrate side is lower than that of the mask stage,
The vibration of the main body column caused by the driving reaction force is slight.

A second exposure apparatus according to the present invention is an exposure apparatus for transferring a predetermined pattern onto a substrate (W) via a projection optical system (PL), and includes a substrate stage (WST) for holding the substrate. A stage base (64) that movably supports the substrate stage; a substrate driving device (70) that drives the substrate stage; and a main that holds the projection optical system and movably supports the stage base. A frame (20).

According to this, since the stage base that movably supports the substrate stage is movably supported by the main frame that holds the projection optical system, the reaction force is generated when the substrate stage is driven (moved). Is not transmitted to the mainframe via the stage base. Therefore,
The main frame does not vibrate or oscillate due to the reaction force of the substrate stage, shortening the positioning settling time of the substrate stage and improving the positioning accuracy (in the case of a stationary exposure type exposure apparatus such as a stepper or an EB exposure apparatus) Alternatively, it is possible to shorten the synchronization settling time of the mask and the substrate stage and the synchronization accuracy (in the case of a scanning exposure apparatus such as a scanning stepper). Therefore, it is possible to improve the overlay accuracy as well as the throughput.

In this case, the limit mechanism (84A, 84B, 86A, 8A) for limiting the movement of the stage base.
6B, 80) may be provided. The restriction mechanism may be an actuator system that applies a compensation force to the stage base in a direction substantially opposite to a reaction force generated in the stage base when the substrate stage is driven by the driving device. . In such a case, a compensation force for canceling the reaction force generated on the stage base by the actuator system is given to the stage base.
The stage base can be stopped at a predetermined position when driving the substrate stage by the driving device.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS << First Embodiment >> A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 schematically shows a configuration of an exposure apparatus 10 according to the first embodiment. The exposure apparatus 10 is a so-called reduction projection exposure apparatus that transfers a pattern of a reticle R as a mask onto a wafer W as a substrate by a so-called step-and-scan method, that is, a so-called scanning stepper.

The exposure apparatus 10 includes an illumination optical system 12 that illuminates the reticle R, a reticle stage RST as a stage that holds the reticle R and moves in a predetermined scanning direction (here, the X-axis direction). A projection optical system PL disposed below the reticle stage RST and held by the main body column 14; a wafer stage device 15 disposed below the projection optical system PL for driving a wafer W as a substrate in the XY two-dimensional directions; ing.

The illumination optical system 12 is connected to a non-illustrated excimer laser light source (for example, having a wavelength of 248) disposed on the back side of FIG.
nm krF excimer laser, 193 nm wavelength ArF
Excimer lasers, are connected to the F ₂ excimer laser) with a wavelength of 157 nm. The illumination optical system 12 includes a relay lens, a condenser lens, a blind, and the like. The laser beam after shaping by the beam matching unit is used to uniformize the illuminance, reduce speckles, and limit the beam cross-sectional shape. Reticle R
The upper slit-shaped illumination area is illuminated.

The main body column 14 is a first frame as a main frame horizontally supported by a plurality of (here, four) vibration isolating mounts 18 above a base frame (frame caster) 16 installed on an installation floor. 20 and
A second gantry 22 fixed to an upper portion of the first gantry 20 is provided.

The first gantry 20 includes an upper plate 24 horizontally held by the four vibration-isolating pads 18, and a hanging base 26 suspended below and supported by four columnar members 25 below the upper plate 24. It is constituted by.

The second gantry 22 has four columns 28 planted on the upper surface of the upper plate 24 and a reticle stage base 3 as a base horizontally held by the columns 28.
0.

The reticle stage RST has a plurality of air pads 32 fixed to the bottom surface thereof, and is supported above the reticle stage base 30 by the air pads 32. This reticle stage RS
T is driven in a predetermined stroke range in the X-axis direction which is the scanning direction by the driving device 40. The reticle stage RST is provided with a reticle fine movement stage (not shown) that sucks and holds the reticle R and minutely drives the reticle R in the non-scanning direction (Y-axis direction). However, since the driving of the reticle R in the non-scanning direction (Y-axis direction) is less relevant to the present invention, the description of the non-scanning direction driving system of the reticle R will be omitted in the following description. .

Here, a specific configuration and the like of the driving device 40 will be described with reference to FIG. As shown in the perspective view of FIG. 2, movers 36A and 36B each having a built-in coil and extending in the X-axis direction are provided integrally at substantially the center in the Z-direction on both sides of the reticle stage RST in the Y-direction. A pair of stators 38A and 38B having a U-shaped cross section are arranged to face the movers 36A and 36B, respectively. Each of the stators 38A and 38B includes a stator yoke and a number of permanent magnets that generate alternating magnetic fields and are arranged at predetermined intervals along the extending direction of the stator yoke. That is, in the present embodiment, the moving coil 36A and the stator 38A constitute a moving coil type linear motor 40A, and the moving element 36B and the stator 3A.
8B and moving coil type linear motor 40
B is configured. The drive device 40 described above is configured by the pair of linear motors 40A and 40B. These linear motors 40A and 40B are controlled by a main controller 80 (see FIG. 3) described later.

Reaction actuators 49A and 49B composed of voice coil motors are connected to both ends in the longitudinal direction of the one stator 38A via rectangular plate-shaped mounting members 42A and 42B, respectively. One reaction actuator 49A includes a mover 44A composed of an arm member connected to the mounting member 42A, and a stator 46 for driving the mover 44A in its axial direction (X-axis direction).
A. The stator 46A is fixed to a first vertical member 48 formed of a plate-like member that is planted on the installation floor and is disposed along the YZ plane (see FIG. 1). The other reaction actuator 49B includes a mounting member 42B.
A movable member 44B composed of an arm member connected to the movable member 44B and a plate-like member driven in the axial direction (X-axis direction), planted on the installation floor, and connected along the YZ plane. The stator 46 fixed to the second vertical member 50
B.

Similarly, reaction actuators 49C and 49D each composed of a voice coil motor are connected to both ends of the other stator 38B in the longitudinal direction via rectangular plate-shaped mounting members 42C and 42D, respectively. The reaction actuator 49C includes a mover 44C composed of an arm member connected to the mounting member 42A,
Stator 46C that drives 4C in its axial direction (X-axis direction)
The stator 46C includes a first vertical member 48
It is fixed to. The reaction actuator 49D includes a mover 44D composed of an arm member connected to the mounting member 42D, and a stator 46D that drives the mover 44D in its axial direction (X-axis direction).
The stator 46D is fixed to the second vertical member 50.

The first vertical member 48 and the second vertical member 50
The upper and lower ends are connected to each other by a horizontal plate 60 as a connecting member, and the first vertical member 48, the second vertical member 50, and the horizontal plate 60 make the stator 38A,
A gate-shaped frame 58 is configured as a support member that movably supports the reticle stage base 30 with respect to the reticle stage base 30. The first vertical member 48 and the second vertical member 50 have different frequency characteristics from each other. Here, the resonance frequency of the first vertical member 48 is 40, for example.
[Hz], the resonance frequency of the second vertical member 50 is 30 [H
z].

Normally, when no force is applied to reticle stage RST (at the time of stopping or moving at a constant speed), reaction actuators 49A and 49B and reaction actuators 49C and 49D are operated by main controller 80 described later.
4A, a tensile force of F ₁ = F ₂ = F (including F = 0) is applied to the stators 38A and 38B to bring the stators 38A and 38B into a predetermined state. Fixed in neutral position.

That is, in this embodiment, the stator 38A is controlled by the reaction actuators 49A and 49B.
An urging device for applying a force to both ends in the X-axis direction, which is the scanning direction, is configured.
D constitutes an urging device that applies force to both ends in the X-axis direction, which is the scanning direction of the stator 38B.

As shown in FIG. 2, the reticle stage RST has a concave portion 52 having a rectangular cross section formed on the upper surface thereof, and a rectangular opening 52a is formed at the center of the inner bottom surface of the concave portion 52.
Are formed. The reticle R is placed in the recess 52 so as to cover the opening 52a. FIG. 1 shows a state in which the reticle R is placed on the upper surface of the reticle stage RST for convenience of illustration. ing.

A pair of corner cubes (not shown) are provided on the −X side of the reticle stage RST, and a reticle laser interferometer (hereinafter, “reticle interferometer”) is provided through the pair of corner cubes. Briefly) 53
Thus, the X direction position of reticle stage RST is measured at a predetermined resolution, for example, about 0.5 to 1 nm. The reticle interferometer 53 is the second gantry 2 of FIG.
It is fixed to 2. Although not shown, the reference mirror (fixed mirror) of the reticle interferometer 53 is fixed to the lens barrel of the projection optical system PL. The measured value of the reticle interferometer 53 is
It is supplied to a main controller 80 described later (see FIG. 3).

On the lower surfaces of the mounting members 42B and 42D,
As shown in FIG. 2, a moving mirror 54 composed of a plane mirror is provided.
A, 54B are fixed, and these movable mirrors 54A,
The X position of each of the stators 38A and 38B is measured at a resolution of, for example, about 0.5 to 1 nm by a stator laser interferometer 56 (see FIG. 1) as a position detector via 54B. The stator laser interferometer 56 is fixed to the second mount 22 in FIG. 1 via a support member (not shown). Reference mirror (fixed mirror) of this laser interferometer for stator 56
Although not shown, is fixed to the second gantry 22 (or the projection optical system PL). The measured value of the stator laser interferometer 56 is also supplied to a main controller 80 described later.

Returning to FIG. 1, the projection optical system PL includes the first
It is inserted from above into a circular opening provided substantially at the center of the upper plate 24 constituting the gantry 20, and is screwed through a flange 57 provided slightly below the center in the height direction of the lens barrel. To the upper plate 24. In the projection optical system PL, the direction of the optical axis AX is the Z-axis direction, and here, a plurality of lens elements arranged at predetermined intervals along the optical axis AX direction so as to have a telecentric optical arrangement on both sides. Is used. The projection optical system PL has a predetermined projection magnification, for example, 1 /
This is a reduction optical system having 5 (or 1/4). For this reason, the reticle R by the illumination light from the illumination optical system 12
Is illuminated, this reticle R
Of the circuit pattern in the illumination area of the reticle R through the projection optical system PL by the illumination light having passed through the slit-shaped illumination area on the wafer W having a surface coated with a photoresist. It is formed in a conjugate exposure area.

The wafer stage device 15 has a predetermined clearance (for example, a clearance of several μm) with respect to the upper surface of the suspension base 26 by the plurality of air pads 62.
A wafer stage base 64 as a stage base made of a rectangular plate-like granite which is levitated and supported via an X stage 66 mounted on the wafer stage base 64 and movable in the X-axis direction which is the scanning direction. A Y stage 68 movable on the X stage 66 in the Y-axis direction, which is a non-scanning direction, and a substrate driving device 70 for driving the X stage 66 and the Y stage 68. Here, the substrate driving device 70 includes an X linear motor 72X that drives the X stage 66 on the wafer stage base 64,
A Y linear motor 72Y that drives the Y stage 68 on the X stage 66 is representatively shown (see FIG. 3). A wafer W is fixed on the Y stage 68 via a Z · θ table (not shown), a wafer holder, and the like, for example, by vacuum suction.

Therefore, in this embodiment, the wafer W is held by the Y stage 68 and the X
A wafer stage WST as a substrate stage that can be moved in two-dimensional Y is configured. In the following description, wafer stage WST will be described as a single two-dimensional moving stage unless otherwise required. Of course, instead of the wafer stage WST having a two-stage structure including the Y stage 68 and the X stage 66, the XY
It is also possible to provide a wafer stage driven in the plane as a substrate stage.

The position of the wafer stage WST in the XY plane is determined by a wafer laser interferometer (hereinafter, referred to as a “fixed”) fixed to the first mount 20 via a movable mirror 74 fixed to the Y stage 68.
(Referred to as a “wafer interferometer”) 76 at a predetermined resolution, for example, about 0.5 to 1 nm. The measurement value of the wafer interferometer 76 is sent to a main controller 80 described later.

FIG. 3 shows a main part of a control system of the exposure apparatus 10. This control system is mainly configured by a main controller 80 including a microcomputer (or a workstation). The main controller 80 includes:
A reticle interferometer 53, a wafer interferometer 76,
The stator laser interferometer 56 and the like are connected, and the output side thereof includes reaction actuators 49A to 49D, linear motors 40A and 40B, and X linear motors 72X and Y.
The linear motor 72Y and the like are connected. The main control device 80 includes these reaction actuators 49A to 49A.
49D, the linear motors 40A and 40B, the X linear motor 72X, the Y linear motor 72Y, and the like, as well as the entire device.

Next, the flow of an exposure processing operation in the exposure apparatus 10 configured as described above will be briefly described.

First, under the control of the main controller 80, reticle loading and wafer loading are performed by a reticle loader system and a wafer loader system (not shown), and a reticle microscope (not shown) and a reference (not shown) on the Y stage 68. Mark board,
Preparation operations such as reticle alignment and baseline measurement are performed according to a predetermined procedure using an alignment detection system (not shown).

Thereafter, the main controller 80 uses an alignment detection system (not shown), for example, as disclosed in
An alignment measurement such as EGA (Enhanced Global Alignment) disclosed in Japanese Patent No. 429 is performed. In such an operation, when movement of wafer W is necessary, main controller 80 moves wafer stage WST in a desired direction via substrate driving device 70. After the completion of the alignment measurement, the exposure operation of the step-and-scan method is performed as follows.

In this exposure operation, first, the wafer W
The main controller 80 controls the wafer stage WST such that the XY position of the wafer stage becomes the scanning start position for the exposure of the first shot area (first shot) on the wafer W.
Is moved. At the same time, main controller 80 moves reticle stage RST such that X position of reticle R becomes the scanning start position. Next, main controller 80 controls reticle R measured by reticle interferometer 53.
Based on the X position information of the wafer W and the XY position information of the wafer W measured by the wafer interferometer 76,
Reticle R (reticle stage RST) and wafer W (wafer stage WST) via 40B and driving device 70
Are synchronously moved in the opposite directions along the X-axis direction at a speed ratio corresponding to the projection magnification of the projection optical system PL.
The pattern of the partial area of the reticle R illuminated by the slit-shaped illumination light is sequentially transferred to the shot area on the wafer W. Since the partial areas illuminated by the slit-shaped illumination light sequentially move in synchronization with the synchronous movement, when one synchronous movement is completed, the entire surface of the pattern area is accurately transferred to the shot area on the wafer W. That is, scanning exposure is performed in this manner.

When the transfer of the reticle pattern to one shot area is completed as described above, wafer stage WST is stepped by one shot area in the Y-axis direction, and scanning exposure is performed for the next shot area. In this way, the stepping and the scanning exposure are sequentially repeated, and the required number of shot patterns are transferred onto the wafer W.

At the time of the above scanning exposure, reticle stage RST is driven at a high speed, and wafer stage WST is also driven in the X-axis direction at a speed 1/4 or 1/5 thereof. The speed at the time of scanning exposure of the reticle stage RST is usually the same as that of the reticle stage RST from the viewpoint of improving throughput.
Drive system, in this case, the maximum speed at which the linear motors 40A and 40B can be driven.
A large thrust acts on the movers 36A and 36B during the acceleration and deceleration of ST. Accordingly, a reaction force in the opposite direction to the thrust and having the same magnitude is generated in the stators 38A and 38B, but in the present embodiment, the reticle stage base 30 and the stators 38A and 38A,
There is no mechanical connection with the stators 38A, 38B.
Are movable relative to the reticle stage base 30 so that the reaction actuators 49A, 49B, 49C,
Since the reticle stage base 30 is supported by the gate-shaped frame 58 via 49D, the reticle stage base 30 does not vibrate due to the above reaction force.

In the first embodiment, as is clear from FIGS. 1 and 2, the driving point of the reticle stage RST, that is, the thrust generating position of the linear motors 40A and 40B is determined by the height of the reticle stage RST. Direction (Z direction)
Of the reticle stage RST, and is in a plane including the position of the center of gravity of the reticle stage RST. Accordingly, the reaction force of reticle stage base 30 for maintaining the horizontal attitude of reticle stage RST becomes almost zero, and as a result, the stimulating force on reticle stage base 30 in the Z direction also becomes zero. Therefore, even if reticle stage RST is driven at a high speed, reticle stage base 3
0 and the body column 14 containing it are not affected.

When the reticle stage RST is driven, a reaction force of the stage driving force acts on the stators 38A and 38B, and unless any compensation force is applied to the stators 38A and 38B, the reaction force causes the stators to fail. 38A and 38B move along the X-axis direction in a direction opposite to the reticle stage RST. However, in the present embodiment, the reaction actuators 49A to 49D controlled by the main controller 80 are used.
The main controller 80 controls the reaction actuators 49A to 49D by various control methods as described below, so that the stator 38A,
38B is held in a neutral position.

First Control Method This first control method is based on a thrust command value of reticle stage RST and a corresponding compensating force, that is, reticle stage RS by linear motors 40A and 40B.
The feed-forward control of the reaction actuators 49A to 49D is performed to generate a compensating force for substantially canceling the reaction force acting on the stators 38A and 38B when the T is driven.

In the following, for convenience of explanation, the stators 38A and 38B will be referred to as the stator 38, and the reaction actuators 49A and 49C will be referred to as the first reaction actuator 46 ₁ and the reaction actuators 49B and 49D. as ₂ second reaction actuator 49 and shall advance the discussion.
Therefore, in practice, the force acting on each stator and each reaction actuator is half as large as that described below.

Now, when no force acts on reticle stage RST, when stator 38 is in the neutral position in the state of FIG. 4A, reticle stage RST faces left as shown in FIG. 4B. Consider the case of receiving the force f.

In this case, the stator 38 has a rightward reaction force f.
Receive. In order to cancel the reaction force f, a rightward force acting on the stator 38 = a leftward force (that is, F ₂ ′ =
f + F ₁ ′) should be satisfied.

In order to satisfy the above equation, main controller 80 controls second reaction actuator 49 ₂ , for example.
Thrust F ₂ 'and is increased by f from the state of FIG. _{4 (A) (F 2'} = F + f). Alternatively, when F ₁ = F ≧ f holds, the thrust F ₁ ′ of the first reaction actuator may be reduced by f from the state of FIG. 4A (F ₁ ′ = F−f). Alternatively, arbitrary forces F ₁ ′ and F ₂ ′ satisfying F ₂ ′ = f + F ₁ ′ are applied to the first reaction actuator 49 ₁ and the second reaction actuator 49 ₂
May be caused by However, in any case, the forces F ₁ ′, F ₂ ′ always acting on the stator 38
It is important that both become tensile forces. The reason is as follows.

When any of the points of action of the forces F ₁ and F ₂ (F ₁ ′, F ₂ ′) is displaced from the horizontal plane including the center of gravity of the reticle stage RST, the reticle is moved by the forces F ₁ and F ₂ . A rotational moment is generated around the center of gravity of the stage RST, and the rotational moment causes the reticle stage RST to rotate around the center of gravity (up and down rotation). In this case, if the forces F ₁ and F ₂ are both tensile forces, the rotation acts in a direction to reduce the rotational moment, and as a result, the rotational moment becomes zero. On the other hand, when the forces F ₁ and F ₂ are compressive forces, the rotation of the stage acts in a direction to increase the rotational moment.

As apparent from FIGS. 1 and 2,
The driving point of the reticle stage RST,
The thrust generating position of the motors 40A and 40B is almost reticle
It is located at the same height as the center of gravity of
Reaction actuator 49 at the same height₁,
49_TwoCompensation force F₁’, F_Two’
F ₁’, F_TwoIs the reticle stage
Assuming that it is off the horizontal plane including the center of gravity of the RST
The deviation is small and therefore
The turning moment is also very small.

As described above, according to the first control method,
As long as F ₂ ′ = f + F ₁ ′ holds, the stator 38
Can be substantially maintained in the neutral position.

However, actually, the compensation force (the reaction actuator 4) calculated based on the thrust command value by the individual difference of the linear motor, the viscous resistance, the back electromotive force, and the like.
9 _1, and 49 ₂ of the thrust), the reaction force acting on the stator 38 in some cases do not match exactly.

Accordingly, an error may occur between the driving thrust of the reticle stage RST (having the same magnitude as the reaction force) and the compensating force, but the stator 38 is not fixed to the reticle stage base 30 as described above. Since it is configured to be freely movable, the error is not transmitted to the reticle stage base 30, and the rotational moment of the reticle stage RST caused by the stage driving force and the compensating force is almost zero. The vibration factor has been almost completely eliminated.

[0069] However, in the first control method for controlling a compensation force generated by the reaction actuator 49 _1, 49 ₂ by calculation on the basis of thrust command value of the reticle stage RST, the stator 38 the error power generated is It moves from the desired position. Therefore, the following second control method has been considered as a technique for effectively preventing such a situation from occurring.

Second Control Method In the second control method, the main controller 80 constantly monitors the actual position of the stator 38 based on the measurement value of the laser always is for servo-controlling the reaction actuator 49 _1, 49 ₂ so that the neutral position. In this case, unlike the first control method, control is inevitably performed by a feedback loop, so that the control response is likely to be delayed. However, the reaction force acting on the stator 38 due to the stage driving (stage driving thrust) substantially coincides) with even if errors in the compensation force, it is possible to generate a compensation force counteracting substantially the reaction force produced during stage driving by reaction actuator 49 _1, 49 _2, it is possible to compensate for the error force ,
The reaction force and the compensation force can be made substantially the same.

In this case, the position detector of the stator 38 is not limited to the laser interferometer, but may be a potentiometer or a linear encoder, or may be a proximity sensor or the like. Even in such a case, the stator 38 can be maintained at the predetermined neutral position by recognizing the amount of deviation from the optimum position.

As is apparent from the above description, in the first embodiment, the main controller 80 controls the urging device based on the position information from the stator laser interferometer 56 as the position detector. Reaction actuator 4
A control system for servo-controlling 9 ₁ and 49 _{2 so} that the stator 38 is at a fixed position is configured. Further, the reaction actuators 49 ₁ and 49 ₂ constitute a compensating force generating mechanism, and the main controller 80 controls the reaction actuators 49 ₁ and 49 ₂ according to the direction and magnitude of the reaction force received by the stator 38. Has been realized. Further, reticle stage RST, linear motor 4
0A, 40B and reaction actuator 49A-
The stage device according to the present invention includes 49D and the like.

As described above, according to the stage device constituting the exposure apparatus 10 according to the first embodiment, the reticle is caused by the error between the reaction force accompanying the movement of the reticle stage RST and the compensation force. Vibration of the main body column 14 provided with the stage base 30 can be almost certainly prevented.

In this embodiment, the reaction actuators 49 ₁ , 49 ₂ provided at both ends of the stator 38 are provided.
Since the first vertical member 48 and the second vertical member 50 to which are fixed are connected to each other by the horizontal plate 60 to form the gate-shaped frame 58, rigidity can be improved. Further, since the first and second vertical members 48 and 50 have different resonance frequencies, it is possible to improve frequency characteristics in a low frequency range.

According to exposure apparatus 10 of the first embodiment, wafer stage base 64 movably supporting wafer stage WST is movably supported by first gantry 20 holding projection optical system PL. ing. That is,
Since the wafer stage WST is floated and supported on the suspension base 26 constituting the first gantry 20, when the reaction force acts on the wafer stage base 64 when the wafer stage WST is driven (moved), the reaction force acts on the wafer stage base 64.
Moves in the direction opposite to wafer stage WST, thereby absorbing the reaction force. Therefore, the driving reaction force of wafer stage WST is not transmitted to first gantry 20 and other portions of main body column 14 via wafer stage base 64. In this case, if the air resistance and the like are ignored, the momentum of the system including the wafer stage WST and the wafer stage base 64 is preserved, and the center of gravity of the system does not move.

Incidentally, compared to the mass (weight) of wafer stage WST, wafer stage base 64 made of granite is used.
Since the mass (weight) of the wafer stage WST is much larger, the wafer stage base 64 generated by the reaction force when the wafer stage WST is driven can be understood from the principle of the action / reaction.
Is small.

Accordingly, the exposure apparatus 10 of the first embodiment
According to the above, when the reticle R and the wafer W are synchronously moved to transfer the reticle pattern onto the wafer W via the projection optical system PL, that is, the reticle stage RST at the time of scanning exposure
And the error force between the driving reaction force and the compensating force, and the vibration of the main body column 14 caused by the driving reaction force of the wafer stage WST, whereby the reticle stage RST The throughput can be improved by shortening the synchronization settling time of wafer stage WST, and the exposure accuracy (overlay accuracy) can be improved by improving the synchronization accuracy.

Further, the first pedestal 20, that is, the main body column 14 vibrates due to the driving reaction force of the wafer stage WST at the time of alignment or stepping between shots.
Alternatively, it is possible to shorten the positioning settling time of wafer stage WST and improve the positioning accuracy without swinging.

[0079] In the above embodiments, configuring the biasing device providing a force to each end of the stator 38 by reaction actuator 49 _1, 49 ₂ connected via an attachment member 42A~42D across the stator 38 Although the case has been described, the present invention is not limited to this.

[0080] For example, FIG. 5 (A), the as shown in the conceptual view of (B), connected to one end of the stator 38 to the reaction actuator 49 _2, the arm member 77 to the other end of the stator 38 and The first vertical member 48 via the buffer mechanism 79
May be connected. As the buffer mechanism 79, a spring such as a leaf spring, a disc spring, a coil spring, or the like, a magnetic coupling mechanism, or the like can be used. In this case, the cost can be reduced as compared with the case where the reaction actuator is provided on both sides of the stator.

For example, consider a case where a coil spring having a spring constant k is used as the cushioning material 79. Reticle stage R
In the state of FIG. 5A where no force acts on ST, the cushioning material 7
9 extends by a predetermined amount x and pulls the stator 38 to the right side in the figure with a force F ₁ = kx, and the second reaction actuator 49 ₂ causes the stator 3 to move with a force F ₂ that balances the force F _1.
8 is pulled to the left in FIG.
8 is in the neutral position. That is, F ₁ = k
When x = F ₂ = F, the stator 38 is in the neutral position.

In this state, assume that reticle stage RST receives leftward force f as shown in FIG. 5B.

In this case, the stator 38 has a rightward reaction force f.
Receive. Due to this reaction force, the stator 38 moves to the right by Δx. As a result, the force by which the cushioning material 79 is displaced by Δx and the buffering material 79 pulls the stator to the right is F ₁ ′ = k
(X−Δx).

However, since the reaction force f = kΔx holds, the sum of the rightward forces in FIG. 5B = f + F ₁ ′ = kΔ
x + {k (x−Δx)} = kx = F, and as long as the second reaction actuator 49 ₂ continues to pull the stator 38 to the left with a force of F ₂ ′ = F ₂ = F, F ₁ ′ + f = F ₂ '
Holds, the stator 38 stops at a position shifted to the right by Δx from the neutral position.

The spring material is not limited to one satisfying the relationship of force f = spring constant k × displacement x, but f = kx ² , f = k
such as x ^3, if (n is an integer except 0) n-th power of the displacement x in proportion to, similar to the above theory holds. In the case of a magnetic coupling mechanism, the same theory holds because the displacement x is proportional to the −2 power.

However, the reason that F ₁ ′ + f = F ₂ ′ is satisfied is that the stator 38 has a distance corresponding to the reaction force due to the reaction force.
Move in the X-axis direction, and the actual driving thrust of the reticle stage RST, that is, the reaction force, changes with time in an oscillating manner. As a result, the stator 38 vibrates. Even if there is no vibrational change, the stationary position of the stator differs depending on the magnitude of the reaction force.
In order to always apply a tensile force to the stator 38, it is necessary to first set a relatively large tensile force.

In order to avoid such inconvenience, an air coupling mechanism may be used as the buffer mechanism 79.
In this case, by always pulling the stator with a constant force F, the aforementioned reaction actuator 4
9 _1, by controlling the compensation force generated in the reaction actuator 49 ₂ in the same manner as when using the 49 _2, it can be substantially maintained stator 38 to the neutral position.

Of course, it is also possible to provide a buffer mechanism on both sides of the stator 38, and to configure an urging device by these buffer mechanisms.

The exposure apparatus 10 according to the first embodiment
Then, reticle stage RST and wafer stage WST move in opposite directions during scanning exposure. Therefore, for example, a Y guide driven in the X-axis direction by a pair of X-axis linear motors and a wafer stage WST driven by the Y-axis linear motor along the Y guides are provided. Of the first and second vertical members 4 in the same manner as the stators 38A and 38B of the above embodiment.
It may be supported by 8, 50. In such a case, the reaction force received by the reaction actuator (compensation mechanism) on the frame 58 at the time of scanning exposure occurs in the direction in which the frames 58 cancel each other, so that the vibration transmitted to the installation floor can be reduced.

Note that the reflecting mirror indicated by the imaginary line 81 in FIG. 1 is fixed to, for example, the second vertical member 50 of the frame 58, and another interferometer is incorporated in the laser interferometer 56 for the stator. Vibration (disturbance) of the frame 58 may be detected via the reflection mirror 81, and the disturbance may be fed back to the control system of the reaction actuators 49A to 49D to reduce the vibration factor of the frame 58.

Further, a reduction in thrust caused by viscous resistance, back electromotive force, etc. of the linear motors 40A, 40B driving the reticle stage RST is experimentally determined in advance, and a command value considering the determined reduction in thrust is used. May be input to the control system of the reaction actuators 49A to 49D. By doing so, the reticle stage RS
It is possible to almost completely eliminate an error factor between the driving thrust of T (the reaction force and the magnitude match) and the compensating force.

In the above embodiment, the vertical members 48 and 50 and the horizontal plate 60 serve as support members for supporting the stator 38.
Although the case of using the gate-shaped frame 58 made of is described above, an integrally formed gate-shaped frame may be used instead, or a mouth-shaped or H-shaped frame may be used. Alternatively, only vertical members similar to the first and second vertical members 48 and 50 may be provided as support members for the stator 38. The first and second vertical members having the same vibration characteristics may be used. Further, by providing a cushioning material between the frame 58 and the installation floor, the reaction force transmitted to the frame 58 may not be directly transmitted to the installation floor.

<< Second Embodiment >> Next, a second embodiment of the present invention will be described with reference to FIGS. Here, the same reference numerals are used for the same or equivalent components as those in the first embodiment, and the description thereof will be simplified or omitted.

The exposure apparatus of the second embodiment is characterized in that a wafer stage device 100 shown in FIG. 6 is provided instead of the wafer stage device 15 of the first embodiment.

This wafer stage apparatus 100 is a square or rectangular granite that is floated and supported by a plurality of air pads 62 on the upper surface of a suspension base 26 and supports a wafer stage WST as a substrate stage so as to be movable in XY two-dimensional directions. And a frame 82 surrounding the wafer stage base 64 and integrally fixed to the wafer stage base 64.

The wafer stage WST is moved by an X linear motor 72X (not shown in FIG. 6; see FIG. 7) in the same manner as in the first embodiment.
X stage 6 driven above in the X-axis direction which is the scanning direction
6 and a Y linear motor 72Y (not shown in FIG. 6,
) On the X stage 66 in the non-scanning direction.
A Y stage 68 driven in the axial direction. Y
A wafer W as a substrate is suction-held on an upper surface of the stage 68 via a wafer holder (not shown). A moving mirror 7 composed of an L-shaped mirror is provided on the upper surface of the Y stage 68.
The position of the Y stage 68 in the XY plane is set to a resolution of, for example, about 0.5 to 1 nm by a wafer interferometer 76 (not shown in FIG. 6, see FIG. 7) via the movable mirror 74. It is measured in.

A pair of Y actuators 84 composed of a voice coil motor are provided on both sides of the frame 82 in the X-axis direction.
A and 84B are arranged at positions facing each other. One Y actuator 84B is composed of a stator fixed to the upper end of a column 88 extending upward from the installation floor, and a mover fixed to the + X side surface of the frame 82 to face the stator. . Notches are formed near the ends of the base frame 16 and the suspension base 26 corresponding to the columns 88 in the + X direction. The configuration on the other Y actuator 84A side is also the same. Here, the point of application of the force in the Y-axis direction applied to the frame body 82 by the pair of Y actuators 84A and 84B is set at substantially the same height as the center of gravity of the Y stage 68.

A pair of X actuators 86 composed of a voice coil motor are provided on both sides of the frame 82 in the Y-axis direction.
A and 86B are arranged at positions facing each other. One X actuator 86A is composed of a stator fixed to the upper end of a column 90 extending upward from the installation floor, and a mover fixed to the + Y side surface of the frame body 82 opposite thereto. . Notches are formed near the ends of the base frame 16 and the suspension base 26 corresponding to the support columns 90 in the + Y direction. The configuration on the other X actuator 86B side is also the same. Here, the point of action of the force in the X-axis direction applied to the frame 82 by the pair of Y actuators 86A and 86B is substantially the same as the center of gravity of the wafer stage WST, that is, the entire X stage 66 and the Y stage 68. It is set at the height position.

A predetermined clearance is provided between the stator and the mover of each of the Y actuators 84A and 84B.
Predetermined gaps are also formed between the stator 84B and the frame 82, respectively. Thus, when driven by the X actuators 86A and 86B, the frame 82 can move in the X direction within a range defined by the gap. Similarly, Y actuators 84A, 8
A predetermined clearance is provided between the stator and the mover of each of X actuators 86A and 86B so that frame 82 can move in the Y direction when driven by 4B, and X actuators 86A and 86B. A predetermined gap is formed between each stator and the frame 82.

On the upper surface on the + X side of the suspension base 26,
A base X interferometer 92X that measures the position of the wafer stage base 64 in the X direction via the frame body 82 is fixed,
The surface of the frame 82 at a portion irradiated with the laser beam in the X-axis direction from the base X interferometer 92X is mirror-finished to form a reflection surface. The base X interferometer 92X is
The position of the wafer stage base 64 in the X direction is measured with reference to a fixed mirror (not shown) fixed to the side surface of the projection optical system PL.

Although not shown in FIG. 6,
Two base Y interferometers 92Y ₁ and 92Y ₂ (see FIG. 7) for measuring the position in the Y direction of the wafer stage base 64 are fixed via a frame 82 to the upper surface on the −Y side of the hanging base 26. And these base Y interferometers 92Y ₁ , 9
By 2Y ₂ , measurement is performed at two different positions of the wafer stage base 64 in the Y direction with respect to a fixed mirror (not shown) fixed to the side surface of the projection optical system PL in the same manner as described above.

FIG. 7 shows a configuration of a main part of a control system of the exposure apparatus according to the second embodiment. This control system
It is mainly configured by a main controller 80 composed of a microcomputer (or a workstation). The main controller 80 has a reticle interferometer 5 on its input side.
3. In addition to the wafer interferometer 76 and the stator laser interferometer 56, a base X interferometer 92X, a base Y interferometer 92Y ₁ ,
92Y ₂ are connected, the reaction actuator 49A~49D on its output side, the linear motor 40A, 40
B and X linear motor 72X, Y linear motor 72
The Y and X actuators 86A and 86B and the Y actuators 84A and 84B are connected.

The configuration and the like of the other parts are the same as those of the first embodiment.

According to the thus configured exposure apparatus of the second embodiment, the operation of the exposure processing step is performed in the same manner as the exposure processing operation of the exposure apparatus 10 of the first embodiment described above. In the operation of this exposure processing step, for example, during scanning exposure, the main controller 80 drives the wafer stage WST in the X-axis direction via the X linear motor 72X. Acts on the base 64.

If no force is applied, the wafer stage base 64 moves in the opposite direction to the X stage 66 due to this reaction force, as in the first embodiment.
In the case of the present embodiment, the main controller 80 controls the X actuators 86A and 86B based on the thrust command value of the X linear motor 72X at this time as described below, and compensates for almost canceling the reaction force. By generating the force, the movement of the wafer stage base 64 is restricted.

Here, a method of controlling X actuators 86A and 86B by main controller 80 will be described. It is assumed that the center of gravity CG of wafer stage WST is located at a distance L ₁ from the thrust generating point of X actuator 86A and a distance L ₂ from the thrust generating point of X actuator 86B, as shown in FIG. .

In the case of FIG. 8, main controller 80 controls X
The thrust P ₁ in which the actuator 86A is generated, the thrust P ₂ where X actuator 86B is generated, both the actuators 86A to a value which can be expressed by the following equation, to control 86B.

P ₁ = L ₂ / (L ₁ + L ₂ ) × P P ₂ = L ₁ / (L ₁ + L ₂ ) × P

Here, P is the magnitude of the reaction force obtained based on the thrust command value of the X linear motor 72X.

More specifically, main controller 80 causes X actuators 86A and 86B to generate forces P ₁ and P ₂ in the same direction as the movement direction of wafer stage WST as compensation forces for the above-mentioned reaction force. The reaction force acting on the stage base 64 is almost canceled, and the movement of the wafer stage base 64 is restricted. In this case, as is clear from the above two equations, P ₁ × L ₁ = P ₂ × L ₂ holds, and the total moment in the XY plane around the center of gravity CG of wafer stage WST is zero.

Further, since wafer stage base 64 made of granite is much heavier than wafer stage WST, wafer stage WST and wafer stage base 6
The center of gravity of the system consisting of the frame 4 and the frame 82 obviously exists in the wafer stage base 64.

Therefore, the above-mentioned wafer stage base 64
Since the rotational moment around the center of gravity of the system caused by the stage drive reaction force received by the motor and the rotational moment around the center of gravity of the system caused by the compensation forces P ₁ and P ₂ are opposite to each other, By applying the compensation force, most of the rotational moment caused by the stage driving reaction force can be canceled. The compensation forces P ₁ and P ₂ act on the same height position as the center of gravity of the moving wafer stage WST, and the total moment in the XY plane around the center of gravity of the wafer stage WST is zero. It is safe to assume that a force of (P ₁ + P ₂ ) = P acts on the center of gravity of wafer stage WST, and compensation forces P ₁ and P ₂ cause no inconvenience to moving wafer stage WST. Has no effect. In this sense, in the present embodiment, it can be said that the X actuators 86A and 86B generate a compensation force of substantially the same magnitude in the opposite direction to the reaction force generated when the wafer stage WST is driven.

Further, for example, at the time of stepping between shots, the main controller 80 drives the Y stage 68 via the Y linear motor 72Y, and the reaction force of the driving thrust acts on the X stage 66. If you do not apply any force,
As described above, the X stage 66 is moved integrally with the wafer stage base 64 in the opposite direction to the Y stage 68 due to the reaction force. In the case of the present embodiment, the main controller 80 controls the Y linear stage at this time. By controlling the Y actuators 84A, 84B in the same manner as the X actuators 86A, 86B described above based on the thrust command value of the motor 72Y, a compensation force having a magnitude substantially equal to the reaction force in the opposite direction is obtained. That is, the movement of the X stage 66 and the wafer stage base 64 is restricted.

Also in this case, Y actuators 84A, 84
The compensating force generated in 4B equivalently acts on the center of gravity of the Y stage 66 in the same manner as described above, and by applying the compensating force, the rotational moment of the system caused by the stage driving reaction force is increased. Partial cancellation is possible.

As described above, in practice, the compensation force calculated based on the thrust command value based on the individual difference of the linear motor, the viscous resistance, the back electromotive force, and the like, and the reaction force acting on the wafer stage base 64 May not be exactly the same.

Therefore, an error between the driving thrust (the reaction force and the magnitude of the reaction force) of wafer stage WST and the compensation force may occur. In the case of the present embodiment, wafer stage base 64 floats above suspension base 26. Supported, hanging base 2
6, that is, it is movable with respect to the first gantry 20, so that the error is not transmitted to the first gantry 20, and the wafer stage base 64 caused by the driving reaction force of the wafer stage WST. Since the rotational moment of the system including the frame 82 and the wafer stage WST can be reduced, the vibration factor of the first gantry 20 is almost completely eliminated.

However, based on the thrust command value of wafer stage WST, actuators 84A, 84B, 86A,
In the above control method for controlling 86B, the above-mentioned error force is generated, and the wafer stage base 64 may move due to this error force.

Therefore, main controller 80 constantly monitors the actual position of wafer stage base 64 based on the measured values of base X interferometers 92X, 92Y ₁ , 92Y ₂ while maintaining the position at the desired position. X actuators 86A, 86B and Y actuators 84A, 8
4B may be servo-controlled. In this case, even if an error occurs between the reaction force (approximately equal to the stage driving thrust) acting on the wafer stage base 64 and the compensating force due to the stage driving, the actuator 6A, 6A, 86B or the Y actuators 84A and 84B, which can compensate for the error force, thereby positioning the wafer stage base 64 at a fixed position, so that vibration factors can be reliably canceled. it can.

In this case, the detector for measuring the position of the wafer stage base 64 is not limited to the laser interferometer, but may be a potentiometer or a linear encoder, or may be a proximity sensor or the like. Even in such a case, the amount of deviation from the optimum position can be recognized and the deviation can be made zero.

As is apparent from the above description, in the second embodiment, the X actuators 86A and 86B, the Y actuators 84A and 84B, and the main controller 80 that controls these actuators cause the X linear actuator as a substrate driving device. When driving the wafer stage WST by the motors 72X and Y linear motors 72Y, an actuator that applies a compensating force to the wafer stage base 64 in a direction substantially equal to the reaction force generated in the wafer stage base 64 in the opposite direction.
A system is configured, and the actuator system also configures a limiting mechanism that limits the movement of the wafer stage base 64.

According to the exposure apparatus of the second embodiment described above, the same effects as those of the first embodiment can be obtained, and the reaction force generated on the wafer stage base 64 by the actuator system can be offset. Therefore, the wafer stage base 64 can be stopped at a predetermined position when the wafer stage WST is driven by the substrate driving device.

However, when the wafer stage WST is driven to stop the wafer stage base 64 at a predetermined position, the center of gravity of the system moves with the movement of the wafer stage WST, and therefore, compared with the reticle stage RST. When the weight (mass) of wafer stage WST is extremely large, etc.,
The main body column 14 tilts due to uneven load (subsidence)
Can occur.

In response to the sinking of the main body column 14 due to the eccentric load, an active anti-vibration mount having an actuator is used as the mount 18, and the active anti-vibration mount corrects the subsidence of the main body column. Is also good. For example, the sinking amount is measured in advance in accordance with the position and weight of wafer stage WST, and the value is stored in a memory, and the actual wafer stage WS
When driving the T, the active anti-vibration mount may be feed-forward controlled in accordance with the position of the wafer stage WST, or the sinking amount is measured in real time using a displacement sensor or the like, and based on the measurement value of this sensor. The active anti-vibration mount may be feedback controlled.

As easily imagined from FIG. 6,
By adjusting the forces P ₁ and P ₂ generated by the X actuators 86A and 86B (or the Y actuators 84A and 84B), it is possible to intentionally rotate the wafer stage base 64. Therefore, in main controller 80,
The direction of the drive axis of wafer stage WST during scanning exposure may be made to coincide with the coordinate axis of reticle R on reticle stage RST while monitoring the measured values of interferometers 92Y ₁ and 92Y ₂ . In such a case, the load on the control system required for controlling the synchronization error between the two stages RST and WST during the scanning exposure can be reduced.

In the first and second embodiments, the case where the present invention is applied to a scanning stepper using excimer laser light as exposure light has been described. However, it is needless to say that the present invention is not limited to this. It is. For example, as the exposure light, a bright line (g line,
i) or a charged particle beam such as light in the soft X-ray region or an electron beam.

Further, as described in the second embodiment,
The technical idea of the present invention in which a stage base that movably supports a stage (substrate stage) is movably supported on a main frame that holds a projection optical system includes a stationary exposure type exposure apparatus such as a stepper, an EB, and the like. The present invention can be suitably applied to an exposure apparatus and the like. In such a case, the reaction force is not transmitted to the main frame via the stage base when the substrate stage is driven (moved). Therefore, the main frame does not vibrate or swing due to the reaction reaction force of the substrate stage, and the positioning settling time of the substrate stage can be shortened and the positioning accuracy can be improved.
Exposure accuracy can be improved as well as the throughput.

[0127]

As described above, according to each of the first to sixth aspects of the present invention, the base for supporting the stage due to the error between the reaction force accompanying the movement of the stage and the compensation force. It is possible to provide an unprecedented excellent stage device that can prevent generation of vibration on the stage base).

According to the exposure apparatus of the present invention, the exposure accuracy can be reduced by suppressing the vibration of the main body column holding the projection optical system due to the driving reaction force of the mask stage during the scanning exposure. There is an effect that it is possible to achieve improvement.

Further, according to the exposure apparatus according to each of the eighth to eleventh aspects, there is an effect that the throughput and the overlay accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a view schematically showing an overall configuration of an exposure apparatus according to a first embodiment.

FIG. 2 is a schematic perspective view showing a configuration of a portion near a reticle stage included in the apparatus of FIG.

FIG. 3 is a block diagram showing a configuration of a main part of a control system of the apparatus shown in FIG.

FIG. 4 is a diagram for explaining a first control method of a reaction actuator for generating a compensation force for a reaction force acting on a stator of a linear motor driving a reticle stage, wherein (A) is a reticle; A diagram showing a force acting on the stator in a state where no force acts on the stage,
(B) is a diagram showing the force acting on the stator when the reticle stage is driven by the force f from the state of (A).

FIGS. 5A and 5B are diagrams for explaining a device according to a modified example.

FIG. 6 is a diagram illustrating a configuration of a main part of an exposure apparatus according to a second embodiment.

FIG. 7 is a block diagram showing a configuration of a main part of a control system of the exposure apparatus of the embodiment of FIG.

FIG. 8 is a diagram for explaining a control method of an X actuator in the device according to the second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Exposure apparatus, 14 ... Main body column, 20 ... 1st mount (main frame), 30 ... Reticle stage base (base), 34 ... Drive device, 36A, 36B ... Mover, 38A, 38B ... Stator, 40, 40A, 40B ...
Linear motor (drive device), 48 first vertical member, 49
A to 49D: Reaction actuator (biasing device,
Compensation force generation mechanism), 50: second vertical member, 56: stator interferometer (position detector), 58: frame (support member), 60: horizontal plate (connection member), 64: wafer stage base (stage) Base), 70 ... substrate driving device, 8
0: Main control device (control system, control device, part of restriction mechanism,
84A, 84B... Y
Actuator (part of restriction mechanism, part of actuator system), 86A, 86B ... X actuator (part of restriction mechanism, part of actuator system), R ... reticle (mask), W ... wafer (substrate) ,
PL: projection optical system, WST: substrate stage, RST: reticle stage (mask stage, stage).

Claims (11)

[Claims] A stage movable with respect to a base;
A stage device comprising a drive device for driving the stage, wherein the drive device relatively moves the mover integrally with the stage in a predetermined direction together with the mover. A stage supported by a supporting member movably in the predetermined direction with respect to the base; and a biasing device for applying a force to both ends of the stator in the predetermined direction. apparatus. 2. A position detector for detecting a position of the stator in the predetermined direction, and a servo unit for controlling the urging device based on position information from the position detector so that the stator is at a fixed position. The stage device according to claim 1, further comprising a control system for controlling. 3. A stage movable with respect to the base;
A stage device comprising: a driving device that drives the stage; wherein the driving device includes a mover integrally attached to the stage, and a stator that relatively drives the mover integrally with the stage in a predetermined direction. A first vertical member connected at one end of the stator in the predetermined direction and disposed along the vertical direction, and connected at the other end of the stator in the predetermined direction and along the vertical direction. At least a second vertical member provided, and a connecting member for connecting the first vertical member and the second vertical member are provided, and the stator is supported movably in the predetermined direction with respect to the base. A stage device comprising a frame. 4. A compensating force generating mechanism for generating a compensating force between the stator and at least one of the first and second vertical members, which substantially cancels a reaction force generated when the stage is driven by the driving device. 4. The device according to claim 3, wherein
A stage device according to item 1. 5. The compensation force generating mechanism includes at least two reaction actuators provided between the stator and the first and second vertical members, respectively, wherein a direction of a reaction force received by the stator and The stage device according to claim 4, further comprising a control device that controls the reaction actuator according to the size. 6. The stage device according to claim 3, wherein the first vertical member and the second vertical member have different frequency characteristics. 7. An exposure apparatus for synchronously moving a mask and a substrate to transfer a pattern of the mask onto the substrate via a projection optical system, wherein the stage according to any one of claims 1 to 6. An exposure apparatus, comprising: an apparatus; wherein the base forms a part of a main body column holding the projection optical system, and the stage is a mask stage holding the mask. 8. An exposure apparatus for transferring a predetermined pattern onto a substrate via a projection optical system, comprising: a substrate stage for holding the substrate; a stage base for movably supporting the substrate stage; and the substrate stage. An exposure apparatus, comprising: a substrate driving device that drives the substrate; and a main frame that holds the projection optical system and movably supports the stage base. 9. The exposure apparatus according to claim 8, further comprising a restriction mechanism for restricting movement of the stage base. 10. The actuator system, wherein the limiting mechanism applies a compensating force to the stage base in a direction substantially opposite to a reaction force generated in the stage base when the substrate stage is driven by the driving device. The exposure apparatus according to claim 9, wherein: 11. The substrate stage according to claim 8, wherein the substrate stage is movable in two orthogonal axis directions, and the stage base is movable in the same direction as the substrate stage. 3. The exposure apparatus according to claim 1.