JP2000347741A - Stage controller, stage device and exposing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stage controller capable of performing highly accurate control. SOLUTION: A target position generator 40 generates a reference signal RS1, for instance, for a wafer stage unit WS. A controller 44 controls the movement of a stage in accordance with a control signal CS1. A laser interference device 32 detects the position of the stage, and a feedback signal FS1 is generated. An operating part 43 outputs a deviation signal corresponding to the difference between the reference signal RS1 and the feedback signal FS1. A compensating circuit 49(#1) eliminates a specific frequency band component included in the deviation signal ES1 and outputs the control signal CS1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and a stage control apparatus and a stage apparatus suitable for highly accurately controlling the position of a moving object such as a mask (reticle) and a wafer used in the exposure apparatus.

[0002]

2. Description of the Related Art In a photolithography process in a manufacturing process of a micro device such as a liquid crystal display, a semiconductor device, an imaging device (such as a CCD), and a thin film magnetic head,
2. Description of the Related Art An exposure apparatus that projects an image of a circuit pattern formed on a reticle onto a photosensitive substrate such as a wafer or a glass plate having a surface coated with a photoresist via a projection optical system is used. 2. Description of the Related Art As an exposure apparatus, a step-and-repeat type exposure apparatus (stepper) configured to collectively project a reticle pattern onto each shot area of a wafer is known. When the exposure of one shot area is completed, the wafer is moved to perform the exposure of the next shot area, and this is sequentially repeated. Also, in order to enlarge the exposure range of the reticle pattern, the exposure light from the illumination optical system is limited to a slit shape, and a part of the reticle pattern is reduced and projected on the wafer using the slit light,
A step-and-scan type exposure apparatus in which a reticle and a wafer are synchronously scanned with respect to a projection optical system is also used.

In an exposure apparatus, a stage device is used to position a reticle and a wafer (or a substrate) with high accuracy, or to scan a reticle and / or a wafer with high accuracy at a constant speed. In this type of stage device, for example, a linear motor is used as a driving mechanism for driving the stage at high speed and in a non-contact manner. The linear motor includes a stator and a moving element. When one of the stator and the moving element includes a coil, the other includes a magnetic body such as a magnet.

When the driving mechanism including the stator and the moving element is in an accelerated state, a reaction force corresponding to the mass and acceleration of one of the stator and the moving element acts on the other. In some cases, the exposure apparatus may generate vibrations due to the vibrations, degrading the exposure accuracy, and may interfere with high-speed processing.

In order to deal with such a point, a passive or active type reaction frame mechanism is known. In the passive type reaction frame mechanism, the reaction frame and the stator, which are provided independently of the exposure apparatus main body, are connected by a reaction bar made of an elastic body, and the above-described reaction force is absorbed by the reaction bar or It is released to the floor via the reaction bar and the reaction frame. In the active type reaction frame mechanism, an actuator such as a voice coil motor that can be electrically controlled is provided in the middle of the reaction bar, and a force that cancels a reaction force is generated by the actuator.

In an exposure apparatus, a stage device is applied to each of a reticle and a wafer in order to eliminate a deviation in a relative positional relationship between the reticle and the wafer, and a PID is used.
(Proportional / Integral / Derivative) type servo control may be performed. For example, by moving the reticle stage according to the positioning error of the wafer stage, the relative position error between the wafer and the reticle is reduced. An outline of this control will be described with reference to FIG.

FIG. 7 is a block diagram showing a servo system of a conventional stage control device applicable to an exposure apparatus. Here, a wafer stage is used for a wafer, and a reticle coarse movement stage and a reticle fine movement stage are used for a reticle. It is assumed that each stage includes an amplifier model, a driving mechanism such as a linear motor, and an interferometer for position detection. For each stage, PI
A negative feedback circuit using a D-type controller is formed. The target position for the wafer stage is given by a target position signal output from a target position generator.
The target position for the reticle coarse movement stage is obtained by quadrupling the target position signal for the wafer stage when the projection magnification of the projection optical system is, for example, 1/4. The target position for the reticle fine movement stage is obtained by converting a position signal detected by the wafer stage interferometer using a conversion matrix defined by a certain conversion relationship. Then, in order to cause each stage to follow the target position, the deviation between the position signal detected by each interferometer and each target position signal is input to each PID type controller, and the resulting thrust command is amplified by an amplifier. To each drive mechanism. After an appropriate acceleration operation, the wafer stage and the reticle fine movement stage move synchronously in opposite directions at a constant speed, and the pattern on the reticle in the area illuminated by the illumination light is sequentially projected on the wafer via the projection optical system. Transcribed.

[0008]

The effect of the reaction force when driving the stage can be suppressed to some extent by the use of the reaction frame mechanism as described above, but it is caused by the reaction force. When the obtained mechanical vibration of the reaction frame includes a low-frequency component having a constant period, the low-frequency component passes through a position detection interferometer and enters a servo system as a low-frequency signal, thereby deteriorating control accuracy. Sometimes. More specifically, it is as follows.

In general, a PID type controller has a very good disturbance follow-up characteristic and disturbance suppression characteristic with respect to a step-like or ramp-like target trajectory. A servo system without the error can be realized. For a book on system type theory, Michio Nakano et al.
(Corona, published in 1989). But,
When the target trajectory includes a periodic signal (in the example shown in FIG. 7, the position signal from the wafer stage becomes the target position signal of the reticle fine movement stage, and the target position signal to be followed is sent to the wafer stage control system. Or a disturbance signal that has entered the control system is a periodic signal (in the example shown in FIG. 7, the control system of the wafer stage and the reticle coarse movement stage). A periodic swing signal (disturbance signal) enters inside.)
According to the "Internal Model Principle" (see the above book),
In some cases, it is not possible to realize a servo system without steady errors.

Accordingly, it is an object of the present invention to provide a stage control device and a stage device capable of performing high-accuracy control. It is another object of the present invention to provide an exposure apparatus having high exposure accuracy using the stage control device or the stage device according to the present invention. Other objects of the present invention will become clear from the following description.

[0011]

Hereinafter, in the examples shown in this section, for ease of understanding, each constituent element of the present invention will be described with typical reference numerals shown in the drawings of the embodiments. The configuration of the present invention or each component requirement is not limited to those restricted by these reference numerals.

According to the present invention, there is provided a stage control device for controlling movement of a stage, comprising: target position generating means (40) for generating a reference signal corresponding to a target position; A control system (44, 46, 48) for controlling the movement of the stage, and detecting means (32, 35, 37) for detecting the position of the stage and generating a feedback signal.
Deviation signal output means for outputting a deviation signal corresponding to a difference between the reference signal and the feedback signal (43, 45, 47)
And a vibration component removing unit (49) that removes a specific frequency band component included in the deviation signal from the deviation signal output unit (43, 45, 47) and becomes a control signal for the control system. A stage controller is provided.

According to the present invention, there is also provided a stage control device for controlling the movement of a first stage and a second stage provided independently of the first stage, wherein the first reference signal corresponding to a target position is provided. Target position generating means (4)
0), a first control system (44) for controlling the movement of the first stage according to an input control signal, and a first detection for detecting a position of the first stage and generating a first feedback signal. Means (32), first deviation signal output means (43) for outputting a deviation signal corresponding to a difference between the first reference signal and the first feedback signal, and the second stage according to an input control signal. A second control system (46) for controlling the movement of the second stage, a second detecting means (35) for detecting the position of the second stage and generating a second feedback signal, and converting the first reference signal according to a predetermined rule. Conversion means (4) for outputting the converted second reference signal;
1) and second deviation signal output means (4) for outputting a deviation signal corresponding to a difference between the second reference signal and the second feedback signal.
5) and first vibration component removing means (4) which removes a specific frequency band component included in the deviation signal from the first deviation signal output means and makes it a control signal for the first control system.
9 (# 1)), and a second vibration component removing unit (49) that removes a specific frequency band component included in the deviation signal from the second deviation signal output unit and becomes a control signal for the second control system. (# 2)) is provided.

Further, according to the present invention, a stage control for controlling the movement of the first stage, the second stage provided independently of the first stage, and the third stage provided on the second stage A target position generating means (40) for generating a first reference signal according to the target position;
A first control system (44) for controlling the movement of the first stage in accordance with the input control signal; and a first detecting means (3) for detecting a position of the first stage and generating a first feedback signal.
2) and first deviation signal output means (4) for outputting a deviation signal corresponding to a difference between the first reference signal and the first feedback signal.
3), a second control system (46) for controlling the movement of the second stage according to an input control signal, and a second detection for detecting a position of the second stage and generating a second feedback signal. Means (35), and first conversion means (4) for outputting a second reference signal obtained by converting the first reference signal according to a predetermined rule.
1) and second deviation signal output means (4) for outputting a deviation signal corresponding to a difference between the second reference signal and the second feedback signal.
5), a third control system (48) for controlling the movement of the third stage according to an input control signal, and a third detection for detecting a position of the third stage and generating a third feedback signal. Means for outputting a third reference signal obtained by converting the first feedback signal according to a predetermined rule.
2) and third deviation signal output means (4) for outputting a deviation signal corresponding to the difference between the third reference signal and the third feedback signal.
7) and a first vibration component removing unit (4) that removes a specific frequency band component included in the deviation signal from the first deviation signal output unit and becomes a control signal for the first control system.
9 (# 1)), a second vibration component removing means (49 (49 (1)) which removes a specific frequency band component included in the deviation signal from the second deviation signal output means and makes it a control signal for the second control system. # 2)), and a third vibration component removing unit (49 (#) that removes a specific frequency band component included in the deviation signal from the third deviation signal output unit and generates a control signal for the third control system. 3)) at least one of the following.

Further, according to the present invention, a stage (23) movably supported by a base (16), a moving element (22) connected to the stage (23), and the moving element (2).
A driving device having a stator (21) cooperating with 2) and driving the stage (23); and the stage (23).
Target position generating means (40) for generating a reference signal corresponding to the target position of the above, detecting means (35) for detecting the position of the stage (23) and generating a feedback signal, the reference signal and the feedback signal A difference signal output means (45) for outputting a difference signal corresponding to a difference between the difference signal output means and a frequency band component caused by the movement of the stage (23) included in the difference signal from the difference signal output means. The stage (2
A stage device including a stage control system (46) for controlling the movement of 3) is provided.

Further, according to the present invention, there is provided a mask stage (reticle stage) for holding a mask (reticle) (R) having a pattern, and a substrate stage for holding a substrate (W). An exposure apparatus formed in (W) is provided. In this exposure apparatus,
The stage device according to the present invention is used as at least one of the substrate stage and the mask stage, or the stage control device according to the present invention is applied to at least one of the substrate stage and the mask stage.

In the stage control device or stage device according to the present invention, the stage is driven or controlled based on a control signal obtained by removing a specific frequency band component by using a vibration component removing means having a specific configuration. With this configuration, even when mechanical vibrations, for example, at a constant period due to a reaction force or the like occur, high-precision control of the stage can be performed. Therefore, by applying the stage control device or the stage device according to the present invention to the exposure device, highly accurate exposure control can be performed.

[0018]

FIG. 1 is a front view showing an embodiment of an exposure apparatus to which the present invention is applied. Here, a step-and-scan type reduction projection type exposure apparatus is shown. A base member (base or surface plate) 13 is provided on the installation surface 11 via four (only two are shown in the figure) vibration isolation pads (vibration isolation mechanisms) 12. The anti-vibration pads 12 are arranged near the four corners of the base member 13, and are not particularly limited. For example, a pneumatic damper or a mechanical damper having a compression coil spring in a damping liquid is used. The base member 13 is made of a highly rigid member such as stone, ceramics, or iron.

A first column 15 holding a projection optical system 14 is provided above the base member 13, and a second column (base or surface plate) 16 is provided above the first column 15. Is provided. On the second column 16, a reticle coarse movement stage unit RCS and a reticle fine movement stage unit RFS are provided as a driving device for moving the reticle R on which the circuit pattern is formed. On the base member 13, a wafer stage unit WS as a driving device for moving a wafer W as a photosensitive substrate is provided. Accordingly, the reticle R and the wafer W are surfaces whose positions in the direction (Z direction in FIG. 1) along the optical axis of the projection optical system 14 are different from each other.
It is movable in a two-dimensional direction (X direction and Y direction) in a plane orthogonal to the optical axis. In this embodiment, since the scanning direction is the Y direction, drive control of the reticle R and the wafer W in the Y direction will be mainly described. The control of the positioning of the reticle R and the wafer W in the X direction and the adjustment of the rotation direction (θ direction) about the Z axis and the inclination angle with respect to the XY plane can be easily carried out as usual, and the description thereof will be omitted.

The wafer stage WS includes a stator 17, a movable member 18 movable in the Y direction with respect to the stator 17, and a stage 19 mounted on the movable member 18. The stator 17 and the moving element 18 cooperating therewith can be provided by a linear motor. Particularly in this embodiment,
The stator 17 includes a slide mechanism 20 such as an air bearing.
The base member 13 is provided so as to be movable in the Y direction. The stator 17 may be fixed on the base member 13. Wafer W coated with a photosensitive agent on its upper surface
Is held on the stage 19 by, for example, sucking and sucking the entire back surface thereof. Moving element 18 and stage 1
Although 9 is shown as a separate member, they may be provided by a common member.

The reticle coarse movement stage unit RCS
A stator 21, a movable member 22 movable in the Y direction with respect to the stator 21, and a stage 23 mounted on the movable member 22 are provided. The stator 21 and the cooperating mover 22 can be provided by a linear motor. In particular, in this embodiment, the stator 21 is moved on the second column 16 by the slide mechanism 24 having an air bearing or the like.
It is provided movably in the direction. The stator 21 may be fixed on the second column 16. Although the mover 22 and the stage 23 are illustrated as separate members, they may be provided by a common member.

The reticle fine movement stage unit RFS
It is provided on stage 23 of reticle coarse movement stage unit RCS. Reticle fine movement stage unit RF
S includes a stator 25, a movable member 26 movably provided in the Y direction with respect to the stator 25, and a stage 27 mounted on the movable member 26. The stator 25 and the cooperating mover 26 may be provided by a linear motor. In this embodiment, the stator 25 is the stage 2
3 fixed on. Further, although the moving element 26 and the stage 27 are illustrated as separate members, they may be provided by a common member. The stage 27 has a function of suction-holding a reticle R having a pattern to be transferred formed on its surface in the vicinity of its periphery with its pattern forming surface facing downward.

A third column 29 is provided on the second column 16. The third column 29 converts light emitted from a light source such as an excimer laser (not shown) into predetermined illumination light to form a reticle. An illumination optical system 30 for leading to R is attached.

A movable mirror 31 is mounted on the stage 19 for the wafer W, and a laser interferometer 32 as a position detecting device is provided on the first column 15 so as to correspond to the movable mirror 31. . The laser interferometer 32 and the movable mirror 31 measure the position of the stage 19 in the Y direction at a predetermined resolution (for example, about 0.001 μm). The measured values are supplied to a control device 33 which can be provided by computer hardware and software, and the wafer stage unit WS is controlled based on the measured values, thereby accelerating, decelerating, and moving the stage 19 during scanning. Positioning is performed.

A movable mirror 34 is mounted on the stage 23 for the reticle fine movement stage unit RFS, and a laser interferometer 35 as a position detecting device is mounted on the third column 29 so as to correspond to the movable mirror 34. Have been. The position of the stage 23 in the Y direction is set to a predetermined resolution (for example, 0.001) by the laser interferometer 35 and the moving mirror 34.
μm). The measured value is supplied to the control device 33, and the reticle coarse movement stage unit RCS is controlled based on the measured value, so that the stage 23 is moved, decelerated, moved, and positioned for scanning.

A movable mirror 36 is mounted on the stage 27 for the reticle R, and a laser interferometer 37 as a position detecting device is provided on the third column 29 so as to correspond to the movable mirror 36. I have. The laser interferometer 37 and the movable mirror 36 measure the position of the stage 27 in the Y direction at a predetermined resolution (for example, about 0.001 μm). The measured value is supplied to the control device 33, and the reticle fine movement stage unit RFS is controlled based on the measured value, so that the stage 27 is moved and positioned for acceleration, deceleration, and scanning.

The illumination optical system 30 illuminates the rectangular pattern area of the reticle R with illumination light extending in a slit shape (rectangular shape) in a direction (X direction) orthogonal to the scanning direction (Y direction) at the time of scanning exposure. Irradiate from above. The illumination area on the reticle R of the slit-shaped illumination light linear in the X direction is located at the center of the circular visual field on the object plane side perpendicular to the optical axis of the projection optical system 14, and has a predetermined reduction magnification β (this In the embodiment, an image of a part of the pattern of the reticle R in the illumination area is projected onto the wafer W at a predetermined resolution through the 1/4) projection optical system 14. As the projection optical system 14, one that projects a reduced inverted image of a pattern formed on the pattern surface of the reticle R onto the wafer W is used.

At the time of scanning exposure, the controller 33 controls the wafer stage unit WS, the reticle coarse movement stage unit RCS and the reticle fine movement stage unit RFS.
In response to this, the reticle R is moved in the + Y direction by scanning at the speed Vm, and in synchronization with this, the wafer W is moved in the −Y direction by the speed Vw.
(= Β · Vm). At the same speed ratio, the reticle R is moved in the -Y direction, and the wafer W is moved.
May be moved in the + Y direction.

At this time, focusing on the reticle coarse movement stage unit RCS, a reaction force acts on the stator 21 as the moving member 22 and the stage 23 accelerate or decelerate.
In this embodiment, since the stator 21 is movable with respect to the second column 16 by the slide mechanism 24, the stator 21 tends to move in the direction opposite to the moving direction of the moving element 22. In order to prevent the influence of the reaction force generated thereby, a reaction frame mechanism is employed.

The reaction frame mechanism includes a reaction frame 38 provided independently of the second column 16 (therefore, the base member 13), and a reaction frame 3
And a reaction force device for generating a force that cancels a reaction force acting on the stator 21 by the movement of the stage 23. Particularly, in this embodiment, a passive type reaction frame mechanism is adopted, and the reaction force device is provided by a reaction bar 39 made of an elastic body or a rigid body connecting the stator 21 and the reaction frame 28. Thereby, the reaction force accompanying the acceleration or deceleration of the stage 23 is released to the installation surface 11 via the reaction bar 39 and the reaction frame 38, so that a certain exposure accuracy is ensured. In addition, reaction bar 3
An active type reaction frame mechanism may be configured by providing an actuator capable of electrically controlling the expansion and contraction of the reaction frame in the middle of the section 9 or the like. Similarly, a reaction frame mechanism may be applied to wafer stage unit WS.

Particularly when a reaction frame mechanism is employed, a frequency band component (for example, a constant low frequency component) transmitted to the reaction frame by moving the stage.
As described above, a steady error may occur in servo control due to the above. Here, focusing on the frequency band component transmitted to the reaction frame 38 by the movement of the stage 23 of the reticle coarse movement stage unit RCS, a method for substantially reducing the steady-state deviation caused by the frequency band component to zero will be described below.

Referring to FIG. 2, there is shown a configuration of a main part of control device 33 shown in FIG. Control device 33
A target position generator 40 as target position generating means;
A conversion circuit 41 as conversion means, a conversion matrix circuit 42 as another conversion means, and an operation unit 4 forming a negative feedback loop for the wafer stage unit WS
3 and controller 44, and arithmetic unit 45 forming a negative feedback loop for reticle coarse movement stage unit RCS
And a controller 46, and a calculation unit 47 and a controller 48 that form a negative feedback loop for the reticle fine movement stage unit RFS. Arithmetic units 43, 45, 47
Function as deviation signal output means, and each of the controllers 44, 46, and 48 functions as a control system. Each of the controllers 44, 46 and 48 is, for example, a P-type
It may be provided by an I-type or PID-type controller.

In this embodiment, the negative feedback loop for the wafer stage unit WS, the reticle coarse movement stage unit RCS, and the reticle fine movement stage unit RFS is provided in order to make the above-mentioned steady-state deviation small or substantially zero. Compensation circuit 4 as vibration component removing means
9 (# 1, # 2, # 3). Here, three compensating circuits 49 (# 1, # 2, # 3) are shown, but the present invention can be implemented by one or two of them. To simplify the circuit configuration, the compensation circuit 4 for the wafer stage unit WS
9 (# 1) only. Each compensation circuit is a compensator 50
And a calculation unit 51, and a specific example of the configuration will be described later.

The target position generator 40 is a stage 19 of the wafer W or the wafer stage unit WS (see FIG. 1).
The reference signal RS1 which gives the target position is generated. The controller 44 controls the driving of the wafer stage unit WS according to the input control signal CS1. The position of stage 19 of wafer stage unit WS is detected by laser interferometer 32 (see FIG. 1), and as a result, feedback signal F
S1 is generated. The operation unit 43 outputs a deviation signal (error signal or difference signal) ES1 corresponding to the difference between the reference signal RS1 and the feedback signal FS1. The compensation circuit 49 (# 1)
The control signal CS1 is generated by removing a specific frequency band component included in the deviation signal ES1.

The conversion circuit 41 converts the reference signal RS1 according to a predetermined rule and outputs a reference signal RS2. For example, the conversion circuit 41 provides a four-fold proportional operation according to the projection magnification of the projection optical system 14 (see FIG. 1). The controller 46 controls the driving of the reticle coarse movement stage unit RCS according to the input control signal CS2. The position of stage 23 of reticle coarse movement stage unit RCS is detected by laser interferometer 35, and as a result, feedback signal F
S2 is generated. The operation unit 45 outputs a deviation signal (error signal or difference signal) ES2 corresponding to the difference between the reference signal RS2 and the feedback signal FS2. The compensation circuit 49 (# 2)
The control signal CS2 is generated by removing a specific frequency band component included in the deviation signal ES2.

The conversion matrix circuit 42 outputs the feedback signal F
S1 is converted according to a predetermined rule, and a reference signal RS3 is output. The controller 48 receives the input control signal CS
In accordance with 3, drive control of the reticle fine movement stage unit RFS is performed. The position of stage 27 of reticle fine movement stage unit RFS is detected by laser interferometer 37,
As a result, a feedback signal FS3 is generated. The calculation unit 47
It outputs a deviation signal (error signal or difference signal) corresponding to the difference between the reference signal RS3 and the feedback signal FS3. Compensation circuit 49
(# 3) generates a control signal CS3 by removing a specific frequency band component included in the deviation signal ES3.

According to one aspect of the invention, if the disturbance signal entering the negative feedback control loop includes a periodic signal, or the target trajectory (eg, the target trajectory provided by reference signal RS3 shown in FIG. 2) includes a periodic signal. In this case, by configuring the compensator 50 in accordance with the above-described internal model principle, servo control in which the steady error is small or the steady error is substantially zero is enabled. A specific configuration example of the compensator 50 will be described with reference to FIGS.

FIG. 3 is a block diagram showing a first embodiment of the compensator 50 shown in FIG. In this embodiment, the compensator 50 adjusts the phase of an output signal of the band-pass filter 52, and a band-pass filter 52 as band-pass means for extracting a specific frequency band component included in the deviation signal ES1, ES2 or ES3. And a phase shifter 53 as a phase adjusting means. The output signal of the phase shifter 53 is supplied to an operation unit 51 as an addition signal output unit. In this case, the operation unit 51 outputs the deviation signal ES1, ES2 or ES.
3, and outputs a signal obtained by adding the output signal of the phase shifter 53 as a control signal CS1, CS2 or CS3.

The drive control modes of the stage include an acceleration mode in which the stationary stage is accelerated to a speed within a constant speed range, a scan mode in which the stage is scanned at a constant speed after the acceleration mode, and a scan mode in which the stage is scanned after the scan mode. There is a deceleration mode for stopping the stage. In the acceleration mode or the deceleration mode, it is desirable that the compensator 50 does not operate in order to improve the rapid followability of the target trajectory. Therefore, in this embodiment, in particular, the compensator 50 includes a switch 54 as a switch for selectively switching the operation of the band-pass filter 52 and the phase shifter 53, that is, whether or not to remove a specific frequency band component. In addition. The switch 54 is turned off in the acceleration mode and the deceleration mode, and turned on in the scanning mode.
The switch 54 can be linked with, for example, a switch for opening and closing a shutter of the optical system. Switch 54
By adopting, the stage can be controlled with high accuracy in the scanning mode, and the rapid followability of the target trajectory is improved.

According to the internal model principle, it is described that a necessary and sufficient condition for the output of the controlled object to follow the target input without a steady-state error is to include a generation model of the target input in a closed loop. In the embodiment shown in FIG. 3, a specific frequency band component that may be included in the deviation signal ES1, ES2 or ES3 is extracted by the bandpass filter 52, and the phase of the extracted signal is shifted by the phase shifter 53. This phase-shifted signal is added to the deviation signal at the time of the next sampling, for example. As a result, a specific frequency band component is canceled in the control signal CS1, CS2 or CS3, and the steady-state error can be reduced or the steady-state error can be made substantially zero, so that extremely high-precision control becomes possible. . as a result,
In the exposure apparatus shown in FIG. 1, extremely high-precision exposure scanning using the reticle R and the wafer W becomes possible,
Exposure accuracy can be improved.

FIG. 4 is a block diagram showing a second embodiment of the compensator 50. In this embodiment, the compensator 50 includes a delay unit 55 that causes a time delay in an input signal,
The arithmetic unit 5 as first addition signal output means for outputting a signal obtained by adding the output signal of the delay means 55 to the deviation signal ES1, ES2 or ES3 as an input signal to the delay means 55
6, the stability compensator 57, and the switch 54 shown in FIG.
And a switch 58 provided for the same purpose.
The output signal of the delay unit 55 is supplied to the operation unit 5 as the second addition signal output unit via the stability compensator 57 and the switch 58.
1 (see FIG. 2), and in this case, the arithmetic unit 51
The output signal of the delay unit 55 is added to the deviation signal ES1, ES2, or ES3 and output as a control signal CS1, CS2, or CS3. More generally, the stability compensator 57 functions as a stabilization compensator for stabilizing the characteristics interposed between the delay unit 55 and the arithmetic unit 51.

As described above, in the embodiment shown in FIG. 4, the principle of repetitive tracking control is used.
This principle can also be explained by the above-described internal model principle, but more intuitively, the principle of the repetitive tracking control can be understood as follows. That is, although it is difficult to satisfy the specification of the tracking error only by the normal feedback control, the tracking error of one cycle before is stored and compensated in advance by using, for example, the fact that the target value has periodicity. Thus, the tracking error can be suppressed as the trial is repeated. In such repetitive control, when trying to follow a target signal or a disturbance signal having an arbitrary period L, a generation mechanism that generates all periodic signals having a fixed period L by using the internal model principle is configured. It is desirable to incorporate it into a closed loop as an internal model. More specifically, a function of a given period L is stored,
This is repeatedly extracted and used for each cycle L. Therefore,
The delay means 55 shown in FIG. 4 includes N stages of dead time elements (z-1) as a periodic function generator having a period L. The delay given by each dead time element (z-1) is a time corresponding to the cycle L. If the sampling time is T,
Since there is a relationship of L = N · T, N and T are set to satisfy this relationship. Delay means 55 and arithmetic unit 56
Constitutes a positive feedback circuit, and the instability of the system in which the positive feedback circuit is introduced is prevented by the stability compensator 57. For additional details on the principle of the repetitive tracking control, refer to “Dynamics and Control of Information Equipment”, edited by The Japan Society of Mechanical Engineers, published by Yokendo, 1996.

FIG. 5 is a block diagram showing a model used for simulating the effect obtained by the embodiment of the present invention. Here, compensator 50 is applied to reticle coarse movement stage unit RCS. As a specific frequency band component, a disturbance signal S having a constant period of 20 Hz is superimposed on the feedback signal FS2.

FIG. 6 shows the controller 46 shown in FIG.
7 is a graph showing a simulation result in a case where is a PID type controller. In FIG. 6, the vertical axis represents the reticle position error (m), and the horizontal axis represents time (second). The result indicated by A is the compensator 5
This is a case where 0 and the arithmetic unit 51 are not used, and the result indicated by B is a case where the compensator 50 and the arithmetic unit 51 are used. As is apparent from FIG. 6, the control error of the embodiment of the present invention is 50 times smaller than that of the prior art.
%.

The embodiments described above are described for the purpose of facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, a semiconductor device, a liquid crystal display,
Not only the exposure equipment used to manufacture thin-film magnetic heads and imaging devices (such as CCDs), but also the exposure equipment that transfers circuit patterns to glass substrates or silicon wafers to manufacture reticles or masks. The invention can be applied.

The exposure apparatus according to the present embodiment assembles a stage apparatus including a number of components such as a reticle fine movement stage unit RFS, a reticle coarse movement stage unit RCS, and a wafer stage unit WS, and also includes a projection system including a plurality of lenses. It can be manufactured by performing optical adjustment of the optical system PL and further performing overall adjustment (electric adjustment, operation confirmation, and the like) using the control device 33 having the compensation circuit 49.

It is desirable that the manufacture of the exposure apparatus be performed in a clean room in which the temperature and the degree of cleanliness are controlled.

[0049]

As described above, according to the present invention,
There is an effect that it is possible to provide a stage control device and a stage device capable of performing highly accurate control and an exposure device having high exposure accuracy. Since the effects obtained by the specific embodiment of the present invention are as described above, the description will be omitted.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of an exposure apparatus to which the present invention is applied.

FIG. 2 is a block diagram showing a main part of the control device shown in FIG.

FIG. 3 is a block diagram showing a first embodiment of the compensator shown in FIG. 2;

FIG. 4 is a block diagram showing a second embodiment of the compensator shown in FIG. 2;

FIG. 5 is a block diagram showing a model used for simulating the effect obtained by the embodiment of the present invention.

FIG. 6 is a graph showing a simulation result by the model shown in FIG. 5;

FIG. 7 is a block diagram showing a servo system of a conventional stage control device applicable to an exposure apparatus.

[Explanation of symbols]

 WS: wafer stage unit RCS: reticle coarse movement stage unit RFS: reticle fine movement stage unit W: wafer R: reticle 17, 21, 25: stator 18, 22, 26: mover 19, 23, 27: stage 20, 24 ... Slide mechanism 31,34,36 ... Movable mirror 32,35,37 ... Laser interferometer 33 ... Control device 38 ... Reaction frame 39 ... Reaction bar 40 ... Target position generator 44,46,48 ... Controller 49 (# 1, # 2, # 3) Compensation circuit 50 Compensator

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Claims (11)

[Claims] 1. A stage control device for controlling movement of a stage, comprising: target position generating means for generating a reference signal corresponding to a target position; and control for controlling movement of the stage according to an input control signal. System, detecting means for detecting the position of the stage and generating a feedback signal, deviation signal output means for outputting a deviation signal corresponding to a difference between the reference signal and the feedback signal, A stage control device comprising: a vibration component removing unit that removes a specific frequency band component included in the deviation signal and uses the frequency signal as a control signal for the control system. 2. The stage control device according to claim 1, wherein said vibration component removing means has switch means for selectively switching whether or not to remove said specific frequency band component. 3. A band-pass unit for extracting a specific frequency band component included in the deviation signal; a phase adjustment unit for adjusting a phase of an output signal of the band-pass unit; 3. The stage control device according to claim 1, further comprising an addition signal output unit that outputs a signal obtained by adding an output signal of the phase adjustment unit to the signal as a control signal for the control system. 4. The vibration component removing means: a delay means for causing a time delay in an input signal; and a signal obtained by adding an output signal of the delay means to the deviation signal is output as an input signal to the delay means. First addition signal output means, second addition signal output means for adding the output signal of the delay means to the deviation signal and outputting the same as a control signal for the control system, the delay means and the second addition signal output means 3. The stage control device according to claim 1, further comprising a stabilization compensating means for stabilizing characteristics interposed between the first and second stages. 5. A stage control device for controlling the movement of a first stage and a second stage provided independently of the first stage, wherein the target position generates a first reference signal corresponding to the target position. Generating means, a first control system for controlling the movement of the first stage according to an input control signal, first detecting means for detecting a position of the first stage and generating a first feedback signal, First deviation signal output means for outputting a deviation signal corresponding to a difference between the first reference signal and the first feedback signal; and a second control system for controlling movement of the second stage in accordance with an input control signal. A second detection unit that detects a position of the second stage to generate a second feedback signal; a conversion unit that outputs a second reference signal obtained by converting the first reference signal according to a predetermined rule; Two reference signals and the second feedback signal Second deviation signal output means for outputting a deviation signal corresponding to the difference between the first and second control signals; and a control signal for the first control system by removing a specific frequency band component contained in the deviation signal from the first deviation signal output means. A first vibration component removing unit, and a second vibration component removing unit that removes a specific frequency band component included in the deviation signal from the second deviation signal output unit to obtain a control signal for the second control system. And a stage control device. 6. A stage control device for controlling movement of a first stage, a second stage provided independently of the first stage, and a third stage provided on the second stage, Target position generating means for generating a first reference signal corresponding to a target position; a first control system for controlling movement of the first stage in accordance with an input control signal; and detecting a position of the first stage First detecting means for generating a first feedback signal by using the first reference signal; first deviation signal outputting means for outputting a deviation signal corresponding to a difference between the first reference signal and the first feedback signal; A second control system for controlling the movement of the second stage, a second detecting means for detecting a position of the second stage to generate a second feedback signal, and converting the first reference signal according to a predetermined rule And output the second reference signal 1 conversion means; second deviation signal output means for outputting a deviation signal corresponding to the difference between the second reference signal and the second feedback signal; and controlling the movement of the third stage according to an input control signal. A third control system that detects a position of the third stage to generate a third feedback signal; and a third output unit that outputs a third reference signal obtained by converting the first feedback signal according to a predetermined rule. (2) conversion means; third deviation signal output means for outputting a deviation signal corresponding to the difference between the third reference signal and the third feedback signal; and identification included in the deviation signal from the first deviation signal output means. A first vibration component removing unit that removes a frequency band component of the first control system and removes a specific frequency band component included in the deviation signal from the second deviation signal output unit; For the second control system A second vibration component removing unit serving as a control signal, and a third vibration component serving as a control signal for the third control system by removing a specific frequency band component included in the deviation signal from the third deviation signal output unit. A stage device comprising at least one of the removing means. 7. A driving device, comprising: a stage movably supported by a base; a moving element connected to the stage; and a stator cooperating with the moving element, the driving device driving the stage; Target position generating means for generating a reference signal according to a target position of the stage; detecting means for detecting a position of the stage to generate a feedback signal; a difference signal corresponding to a difference between the reference signal and the feedback signal And a stage control system that controls the movement of the stage by removing a frequency band component caused by the movement of the stage included in the difference signal from the difference signal output means. A stage device characterized by the above-mentioned. 8. A frame disposed independently of the base and connected to the stator, wherein the frequency band component is caused by a frequency band component transmitted to the frame by movement of the stage. The stage device according to claim 7, wherein: 9. The stage device according to claim 7, wherein the stator is movably supported by the base. 10. A frame disposed independently of the base, and a reaction force device disposed on the frame and generating a force for canceling a reaction force acting on the stator by moving the stage. The stage device according to claim 9, further comprising: 11. An exposure apparatus comprising: a mask stage for holding a mask having a pattern; and a substrate stage for holding a substrate, wherein at least one of the substrate stage and the mask stage forms the pattern on the substrate. An exposure apparatus using the stage device according to any one of claims 7 to 10.