JP2002142491A - Linear motor driver and stage unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a linear motor driver in which dynamic brake is actuated appropriately at the time of power interruption even when an excitation switching system is employed, and a stage unit comprising the driver. SOLUTION: The linear motor driver employing an excitation switching system comprises switching circuits SW1-SW4 for switching excitation of respective coils L1-L4, and a semiconductor relay switch 202 for short-circuiting a circuit including the coils L1-L4 in order to actuate the dynamic brake upon occurrence of power interruption. The switching circuits SW1-SW4 do not operate as power supply is interrupted and switching is turned off. Power supply for the switching circuits SW1-SW4 is thereby provided with a charge/discharge circuit comprising electric double layer capacitors C1-C3 so that the power supply is backed up during effective period of dynamic brake even if power supply to the switching circuits SW1-SW4 is interrupted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor driving device for driving a linear motor and a stage device provided with the driving device.

[0002]

2. Description of the Related Art A linear motor is used for a stage having a long moving stroke in a wafer stage or a reticle stage of a semiconductor projection exposure apparatus. In this linear motor, when a power failure occurs during driving, it is necessary to surely stop the stage. For this reason, it is necessary to operate a dynamic brake at the time of a power failure.

FIG. 9 shows an example of a conventional linear motor drive circuit for driving one coil of a linear motor. Normally, coils of a three-phase linear motor have three phases of a U-phase, a V-phase, and a W-phase. The current controlled to a constant current in the current control circuit 101 is applied to the coil 10 of the linear motor 102.
When it is supplied to 3, the mover provided with the permanent magnet is driven in a predetermined direction. Reference numeral 104 denotes a normally closed mechanical relay that has a configuration in which a contact is closed when a brake signal is input and when the power is turned off. During normal operation, the brake signal is inactive, the mechanical relay 104 operates, and the contacts are open.

In such a configuration, when a power failure occurs, the mechanical relay 104 closes and a closed circuit including the coil 103 is formed. In such a state, when the permanent magnet of the mover attempts to move, a current tends to flow in the closed circuit in a direction that impedes the movement due to the back electromotive force.
As a result, a dynamic brake acts on the magnet of the mover, and the stage is reliably stopped due to a power failure or the like.

On the other hand, in order to improve the exposure accuracy and the throughput at the time of exposure in recent years, a scan type exposure apparatus has been developed, and the thrust of a linear motor has been improved.
In order to improve the thrust of the linear motor, the driving voltage and the driving current are increased, and the power consumption is increased. In order to solve this problem, in an MM type linear motor in which the mover of the linear motor is a magnet, current is supplied only to the coil of the stator where the mover is present, and the magnet of the mover is magnetized. There has been proposed an excitation switching linear motor that switches a coil to be energized in accordance with the movement of the motor. As a result, the coil that does not directly contribute to the thrust of the motor is not energized, and power is saved.

In such an excitation switching type linear motor drive circuit, in addition to the conventional linear motor drive circuit, a switch BOX circuit for switching ON / OFF each coil is required separately. The switch BOX circuit is
In terms of switch response speed, switch contact reliability, malfunction due to noise, size, etc., mechanical relay switches with contacts cannot be used, and photo MOS relay switches or photo couplers and large current MOS-FETs
Switches and the like are used.

[0007]

Such a switch is turned on only when a current flows from the power supply and the control signal is instructed to be turned on. Therefore, when the power supply is stopped due to a power failure or the like, the switch is turned on. Automatically switches on
It becomes FF. In that case, even if both ends of each coil are short-circuited by the mechanical relay 104 in the linear motor drive circuit of FIG. 9, the switch of the switch BOX circuit (not shown) provided in the middle is turned off.
The OPEN state is set for the coil of the linear motor. For this reason, there has been a problem that the dynamic brake may not work properly.

It is an object of the present invention to provide a linear motor drive device that appropriately operates a dynamic brake in a power failure or the like even in an excitation switching method and the like, and a stage device provided with the drive device.

[0009]

FIG. 1 shows an embodiment of the present invention.
The present invention will be described below with reference to the corresponding elements in parentheses using FIGS. According to a first aspect of the present invention, in the linear motor driving device, switching means (SW1 to SW4) for turning on and off a current to coils (L1 to L4) constituting the linear motor (208);
A first power supply unit (209) for supplying power for operating the switching units (SW1 to SW4), a second power supply unit (201) for supplying a drive current for the coils (L1 to L4), and a first power supply unit (201). When the power supply from the power supply means (209) and the second power supply means (201) is stopped,
In order to apply a dynamic brake to the linear motor (208), a short circuit means (202) forming a closed circuit including coils (L1 to L4) and switching means (SW1 to SW4), and a first power supply means (209) ) Is supplying power, the first power supply means (209)
When the supply of power from the second power supply means (201) is stopped, the switching means (S
W1 to SW4) and a charging / discharging means (203) for discharging power so as to back up the power. According to a second aspect of the present invention, in the linear motor driving device according to the first aspect, a third power supply means (211) for supplying power to another circuit of the linear motor driving apparatus, and a first power supply means (209). , Second power supply means (201), and third power supply means (201).
Reset signal generation means for generating an initial reset signal at the time of power-on based on power-off of the third power supply means (211) when power supply from the power supply means (211) is stopped and then turned on again (212). According to a third aspect of the present invention, in the stage device, a stage (8) on which a moving object (5) is mounted;
A linear motor (208) for driving the stage (8) to move the moving object (5);
08) and a linear motor driving device according to claim 1 or 2 for driving the linear motor driving device.

[0010] In the section of the means for solving the above-mentioned problems, the description is made in correspondence with the drawings of the embodiments for easy understanding, but the present invention is not limited to the embodiments.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Before describing an embodiment of a linear motor drive circuit (drive apparatus) according to the present invention, first, a projection using the present linear motor drive circuit will be described. The exposure apparatus and its stage apparatus will be described.

FIG. 1 is a schematic configuration diagram of a projection exposure apparatus.
The projection exposure apparatus mainly includes an illumination optical system 1, a reticle stage device 2, a projection optical system 3, and a wafer stage device 4. FIG. 1 is a view of the projection exposure device as viewed from the front. The projection exposure apparatus employs a slit scan exposure method. The slit scan exposure method is as follows. That is, the reticle 5 is illuminated with the exposure light IL restricted in the form of a slit emitted from the illumination optical system 1, the reticle 5 is driven in one direction, and the reticle 5 is driven in one direction. The exposure light IL scans the entire pattern provided on the reticle 5, and drives the wafer 6 in the opposite direction to the reticle 5 in accordance with this scan. As a result, the entire pattern is projected onto a predetermined area of the wafer 6. Projection exposure is performed via the optical system 3. This is repeated. The slit scan exposure method has a known content (for example, see JP-A-6-140305).

The projection exposure apparatus will be further described with reference to FIGS. In FIG. 1, the direction perpendicular to the paper is X
The axis, the vertical direction is the Z axis, and the horizontal direction is the Y axis.

The reticle stage device 2 includes a reticle base 7, a reticle scanning stage 8, and a reticle fine movement stage 9, and the reticle 5 is mounted on the reticle fine movement stage 9. The reticle scanning stage 8 is also called a reticle coarse movement stage. The reticle scanning stage 8 is driven by a reticle scanning drive device 10, and the reticle fine movement stage 9 is driven by a reticle fine movement drive device 11.
The reticle scanning drive device 10 and the reticle fine movement drive device 11 are connected to and controlled by a control device 12. Control device 1
2 is composed of a microprocessor and peripheral circuits,
Other controls related to the projection exposure apparatus are also performed.

The wafer stage device 4 includes a wafer base 1
3, wafer stage X-axis drive unit 14, wafer stage Y
The wafer 6 is mounted on the wafer stage Y-axis drive unit 15. The wafer stage X-axis driving unit 14 and the wafer stage Y-axis driving unit 15 are driven by a wafer driving device 16, and the wafer driving device 16 is connected to and controlled by the control device 12.

FIG. 2 is a plan view of the reticle stage device 2. The reticle base 7 is formed with two rows of air guides 21a and 21b in the X direction, on which the reticle scanning stage 8 is mounted. A plurality of electromagnets 22a and 22b are embedded outside the air guides 21a and 21b in a row in the X direction, and a permanent magnet (not shown) is embedded on the back surface of the reticle scanning stage 8. The reticle scanning stage 8 includes electromagnets 22a, 22b
And air guides 21a and 21b by permanent magnets (not shown).
Is driven in the X direction along a linear motor system (hereinafter referred to as a linear motor). The driving of the linear motor will be described later.

A reticle fine movement stage 9 is mounted on the reticle scanning stage 8. Further, on the reticle scanning stage 8, actuators 23 and 24 for finely driving the reticle fine movement stage 9 in the X direction, respectively, and Y
An actuator 25 that finely drives in the direction is fixed.
The actuators 23 to 25 are constituted by voice coils, and one end is fixed to the reticle fine movement stage 9. Therefore, the reticle fine movement stage 9 is finely driven in the XY plane with respect to the reticle scanning stage 8 by controlling the current flowing through the voice coil.
It is fixed at a predetermined position on the reticle scanning stage 8.
The reticle fine movement stage 9 includes actuators 23 and 24
Is finely driven also in the rotational direction in the XY plane by adjusting the balance of the control.

Moving mirrors 26, 27 and 28 are fixed to reticle fine movement stage 9 as shown in FIG. Further, laser interferometers 29, 30, 31 are provided to face these movable mirrors 26, 27, 28. The laser interferometers 29, 30, 31 are provided in a fixed relation to the reticle base 7, and the outputs thereof are connected to the controller 12. The combination of the movable mirror 26 and the laser interferometer 29 detects the position of the reticle fine movement stage 9 in the Y direction, and the combination of the movable mirror 27 and the laser interferometer 30 detects the position of the reticle fine movement stage 9 in the X direction. Moving mirror 28
The rotation angle of the reticle fine movement stage 9 in the XY plane is detected by a combination of the laser interferometer 31 and the laser interferometer 31.

FIG. 3 is a plan view of the wafer stage device 4. On the wafer base 13, two rows of air guides 41a and 41b are formed in the X direction, and the wafer stage X-axis drive unit 14 is mounted thereon. A plurality of electromagnets 42a and 42b are embedded in a row in the X direction outside the air guides 41a and 41b, respectively, and a permanent magnet (not shown) is embedded on the back surface of the wafer stage X-axis drive unit 14. The wafer stage X-axis drive section 14 is driven by electromagnets 42a and 42b and permanent magnets (not shown) in the X direction along the air guides 41a and 41b by a linear motor system (hereinafter, referred to as a linear motor). The driving of the linear motor will be described later.

On the wafer stage X-axis drive unit 14, two rows of air guides 43a and 43b are formed in the Y direction, and the wafer stage Y-axis drive unit 15 is mounted thereon. The wafer stage Y-axis driving unit 15 is provided with a stepping motor 44 along the air guides 43a and 43b.
, And is driven in the Y direction via the ball screw 45.

As shown in FIG.
The movable mirrors 46 and 47 are fixed as shown in FIG. Two laser interferometers 48 and 49 are provided facing the moving mirror 46, and a laser interferometer 50 is provided facing the moving mirror 47. The laser interferometers 48, 49, 50 are provided in a fixed relation to the wafer base 13, and the outputs thereof are connected to the controller 12. The combination of the movable mirror 46 and the laser interferometer 48 detects the position of the wafer stage Y-axis drive unit 15 in the Y direction, and the movable mirror 47 and the laser interferometer 5
X of the wafer stage Y-axis drive unit 15 in combination with 0
The position in the direction is detected, and the movable mirror 46 and the laser interferometer 49 are detected.
XY of the wafer stage Y-axis driving unit 15 in combination with
A rotation angle in the plane is detected.

With the reticle stage device 2 and the wafer stage device 4 configured as described above, slit scan exposure can be realized. In the present embodiment, a pattern for one chip is formed on the reticle 5, and one chip is projected and exposed on the wafer 6 by one slit scan exposure. The minute pattern is projected and exposed.

Next, the excitation switching method of the linear motor will be described with reference to the reticle stage device shown in FIG.

As described above, reticle scanning stage 8
Are electromagnets 22a, 22 provided on the reticle base 7.
It is driven by two linear motors on the left and right constituted by b and a permanent magnet provided on the reticle scanning stage 8.
In the linear motor on the left side of FIG. 2, a stator is constituted by the electromagnet 22a, and a permanent magnet provided on the reticle scanning stage 8 corresponding to the electromagnet 22a constitutes a mover. The linear motor on the right side of FIG. 2 forms a stator with the electromagnet 22b,
A permanent magnet provided on the reticle scanning stage 8 corresponding to the electromagnet 22b forms a mover. These linear motors are moving magnet type (MM) linear motors.

Hereinafter, the linear motor on the left side (the electromagnet 22a side) in FIG. 2 will be described. The electromagnet 22a has three phases (U-phase, V-phase, and W-phase). In the present embodiment, 14 electromagnets 22a are provided in the X direction. Therefore, U phase, V
Phase and W-phase coils are alternately overlapped for 14 sets (14 sets).
(× 3 phases = 42 coils) provided at predetermined intervals. Although only seven sets are clearly shown in FIG. Actually, 14 sets are provided. A plurality of permanent magnets provided on the reticle scanning stage 8 side are provided in a predetermined range corresponding to seven electromagnets 22a. In the present embodiment, since the excitation switching method is adopted during slit scan exposure, energization of the electromagnet 22a is energized only in a range corresponding to the permanent magnet of the reticle scanning stage 8.
That is, power is supplied to seven electromagnets 22 a selected according to the position of the reticle scanning stage 8, and power supply to each coil is switched as the reticle scanning stage 8 moves.

According to this method, since no power is supplied to the electromagnet which does not contribute to the driving of the mover, a low power consumption linear motor is realized. 2 (electromagnet 22b
The same applies to the linear motor on the side.

Next, a drive circuit of the linear motor according to the present embodiment will be described. Hereinafter, the linear motor on the electromagnet 22a side in FIG. 2 will be described, but the same applies to the linear motor on the electromagnet 22b side.

FIG. 4 shows a drive circuit of the linear motor according to the present embodiment. As described above, the linear motor 208
Although a three-phase motor of a phase, a V-phase, and a W-phase is used, only one phase will be described here for the sake of simplicity. In the above description, the number of the electromagnets 22a is fourteen, and the excitation switching is performed for seven of them. However, in FIG. 4, the number of the electromagnets 22a is four in order to simplify the description, and two of them are two. Excitation switching is to be performed for each of them. That is, a case will be described where the total number of coils is four and the excitation switching of the two coils is sequentially performed.

In FIG. 4, a current control circuit 201 is controlled by a current control signal and outputs a controlled constant current. The current output from the current control circuit 201 is applied to the coil 20 inside the linear motor 208 by the switch circuit 205 inside the switch BOX circuit 206 via the switches whose switches SW1 to SW4 are turned on.
7 is energized. In FIG. 4, the switches SW2 and SW3 are turned on, and a current flows through the coils L2 and L3. Further, which of the switches SW1 to SW4 are sequentially turned on is designated by a SW switching signal.

In a preparatory state before receiving the current control signal to drive the stage to a predetermined position, the brake signal is set to LOW and the semiconductor relay switch 202 is turned on so that the dynamic brake operates. At this time, since the switches SW2 and SW3 of the switch 205 in the switch BOX circuit 206 are ON, the coil 207
Both ends of the coils L2 and L3 are short-circuited, and the dynamic brake operates.

FIG. 5 is a diagram showing an example of a circuit of one of the switches SW1 to SW4. In FIG. 5, by setting the SW switching signal SW0 to LOW, a current flows through the LED of the photocoupler PC1, and a current flows through the photodiode of the photocoupler PC1. When a current flows through the photodiode of the photocoupler PC1, the gates of the MOS-FETs Q1 and Q2 are driven, the MOS-FETs Q1 and Q2 are turned on, and a drive current can flow through the coil L1 of the linear motor 8. Conversely, by setting the SW switching signal SW0 to HIGH, no current flows to the LED of the photocoupler PC1, and the MOS-FETs Q1 and Q2 are turned off. Each of the switches SW2 to SW4 is configured by a similar circuit.

Next, a case where a power failure such as an instantaneous power failure occurs in a driving state in which a current is flowing will be described with reference to FIG. When a power failure such as an instantaneous power failure occurs, the power failure is detected by a predetermined detection circuit (described later), the brake signal is set to LOW, and the semiconductor relay switch 202 is turned on. Further, since the charging / discharging circuit 203 starts charging from a state in which a SW power supply (described later) is turned on, a predetermined voltage is maintained even when the SW power supply is down due to a power failure such as an instantaneous power failure. Circuit semiconductor relay switch 202, switch B
The signal is supplied to the OX circuit 206 and a control system circuit (not shown).
Therefore, the switch circuit 205 inside the switch BOX circuit 206 holds the state before a power failure such as a momentary power failure, and the dynamic brake can be operated.

That is, when a power failure occurs, the semiconductor relay switch 202, the switches SW2 and SW3, and the coil L
2, L3 constitute a closed circuit. In such a state, when the permanent magnets of the mover positioned corresponding to the positions of the coils L2 and L3 try to move by inertia, back electromotive force is generated in the coils L2 and L3, and the mover is prevented from moving. Current tries to flow in a closed circuit. As a result, a dynamic brake acts on the mover.

FIG. 6 shows a DC-DC as a SW power supply.
Converter 209, charge / discharge circuit 203, power failure detection circuit 2
FIG. The DC-DC converter 209 is
24 VDC is input and outputs a +5 VDC SW power supply having a potential of +5 VDC. DC-DC converter 20
Reference numeral 9 denotes a semiconductor relay switch 202 and a switch BOX 20, as shown in FIG.
Power is supplied to 6. Further, as shown in FIG. 4 or FIG. 6, a charge / discharge circuit 203 is connected to the output of the DC-DC converter 209. The charging current of the charging / discharging circuit 203 is set by the resistor R1 and charges the three electric double-layer capacitors C1 to C3 connected in series while the DC-DC converter 209 is ON. When 24 VDC fails, +5 VDC is discharged via diode D1.
The reason why three electric double-layer capacitors C1 to C3 are connected in series is to ensure a withstand voltage. The resistance R2
R4 are provided for stabilizing the charging operation of the three electric double-layer capacitors C1 to C3.

The power failure detection circuit 210 detects a power failure by detecting a decrease in the potential of 24 VDC. For example, 24VDC
Is reduced to about 18 to 19 VDC, the power failure detection signal is set to LOW. If a power failure detection circuit 210 uses a normally closed terminal or the like of a mechanical relay, it is possible to set a power failure detection signal to LOW at the time of power failure detection, and thereafter hold the LOW signal even when power supply is interrupted. However, if the power of the power failure detection circuit 210 is supplied by the SW power supply 209 (DC-DC converter 209), the power can be backed up by the charge / discharge circuit 203 after the power failure. In this way, a circuit can be formed without using a mechanical relay. Note that the DC-DC converter 209 is a DC-DC converter that can still operate at a voltage at which the power failure detection circuit 210 detects a power failure, and becomes inoperable only after the voltage drops to about 15 to 16 VDC.

The power failure detection signal of the power failure detection circuit 210 is input to the semiconductor relay switch 202 as a LOW signal of the brake signal through a predetermined circuit. further,
The power failure detection signal is fed back to the current control signal of the current control circuit 201, and in a driving state where current is flowing,
When a power failure such as an instantaneous power failure occurs, the current output of the current control circuit 201 is protected from being short-circuited to the ground. That is, the current control circuit 201 turns off the current output when the power failure detection signal is fed back, and is protected from being short-circuited to the ground via the semiconductor relay switch 202.

As described above, even if a power failure occurs, the power of the switch BOX 206 and the semiconductor relay switch 202 is backed up by the charge / discharge circuit 203.
Even with a linear motor drive circuit that employs the excitation switching method, the dynamic brake can be reliably applied. In other words, protection of the linear motor of the excitation switching system which saves power can be reliably achieved. In addition,
The charge / discharge circuit 203 only needs to have a capacity enough to back up at least the time when the dynamic brake needs to be applied.

Second Embodiment A second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, as shown in FIG. 6, a charge / discharge circuit 203 is provided at the output of the DC-DC converter 209.
Even if the input of the C-DC converter 209 is turned off and then turned on again, if it is within the discharge time of the charge / discharge circuit 203,
ON / OFF of the DC-DC converter 209 cannot be recognized. That is, the DC-DC converter 20
9, even if an initial reset circuit, in other words, a power-on reset circuit for resetting at power-on, is provided,
If the time of N is short, the initial reset circuit may not operate.

Therefore, in the second embodiment, as shown in FIG. 7, a second DC-DC converter 211 is used in addition to the first DC-DC converter 209 for the SW power supply. . Second DC-DC converter 211
Functions as a power supply to circuits that do not need to be backed up to activate the dynamic brake in the event of a power failure. The circuit which does not need to be backed up is claimed in claim 3
Corresponds to other circuits.

FIG. 8 shows the second DC-DC converter 21
FIG. 4 is a diagram in which an initial reset circuit 212 is configured using an output of + 5VC having a potential of + 5VDC. The initial reset circuit 212 includes a resistor R5, a capacitor C4, and a diode D2. When the output + 5VC of the second DC-DC converter 211 falls, the output of the initial reset circuit 212 becomes LOW, and the LOW signal becomes AND.
Input to the gate 213. When the input of the AND gate 213 becomes LOW, the AND gate 213 outputs a LOW signal, and the error detection flip-flop 214 is reset. As a result, the error state of the error detection flip-flop 214 is released every time the power is turned on, without inputting the RESET signal from the host. The error detection flip-flop 214 is set by an error detection signal. The error detection signal is a signal generated by detection of various error states such as overcurrent, overvoltage, and overtemperature in the linear motor driving device in addition to the power failure.

The other structure is the same as that of the first embodiment, and the description is omitted.

As described above, even in a linear motor drive circuit that employs the excitation switching method and is capable of operating a dynamic brake, an initial reset circuit can be configured as in the related art. Therefore, even if an external reset signal is not input, the error detection flip-flop and the like can be initially reset.

In the above embodiment, only the linear motor on the electromagnet 22a side may be described, but the description can be similarly applied to the linear motor on the electromagnet 22b side.

Although the above embodiment has been described with reference to the example of the reticle stage device 2, the present invention can be similarly applied to the wafer stage device 4. That is, the above contents are shown in FIG.
Electromagnets 42a and 42b and wafer stage X-axis drive unit 1
4 can be similarly applied to a linear motor constituted by a permanent magnet (not shown) provided on the back surface of the motor.

In the above-described embodiment, the example has been described in which the number of electromagnets of the linear motor is 14, and the number of electromagnets to be energized by switching the excitation is 7, but the present invention is not limited to this. The number of electromagnets of the linear motor may be more than 14 or less than 14. The number of electromagnets to be energized in the excitation switching method may be more than seven or less than seven.

In the above embodiment, the example of the linear motor used for the stage of the projection exposure apparatus has been described. However, the present invention is not limited to this. It can be applied to anything using a linear motor.

In the above embodiment, FIG. 5 shows an example in which a photocoupler and a MOS-FET are used as a switch circuit. However, the present invention is not limited to this. For example, a photo MOS relay switch may be used. That is, the present invention can be applied to all switch circuits that require a constant power supply for ON / OFF switching operation.

In the above embodiment, the example in which the semiconductor relay switch 202 is used and the power supply of the semiconductor relay switch 202 is backed up by the charging / discharging circuit 203 in FIG. 4 has been described. However, the present invention is not limited to this. For example, instead of the semiconductor relay switch 202, a mechanical relay may be used as in the prior art of FIG. 9, and the power supply may not be backed up for this portion.

In the above-described embodiment, an example in which the electric double layer capacitors C1 to C3 are used for the charge / discharge circuit 203 has been described. However, the present invention is not limited to this. For example, another type of capacitor having a large capacity may be used. Alternatively, it may be a rechargeable battery. That is, any charge / discharge circuit that can be charged when the power is turned on and can be discharged when the power is turned off such as a power failure can be used.

[0050]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the present invention, for example, even in a linear motor driving device having a switching means for the excitation switching method, the dynamic brake can be reliably applied to protect the linear motor. According to the second aspect of the present invention, the initial reset signal can be reliably generated even in the linear motor driving device of the first aspect. According to the third aspect of the present invention, the above effects can be achieved in the stage device.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a projection exposure apparatus.

FIG. 2 is a plan view of the reticle stage device as viewed from above.

FIG. 3 is a plan view of the wafer stage device as viewed from above.

FIG. 4 is a linear motor drive circuit according to the first embodiment;

FIG. 5 illustrates an example of one switch circuit.

FIG. 6 is a diagram showing a DC-DC converter, a charge / discharge circuit, and a power failure detection circuit.

FIG. 7 is a diagram illustrating two DC-DC converters according to the second embodiment.

FIG. 8 is a diagram illustrating an initial reset circuit according to a second embodiment.

FIG. 9 shows a conventional linear motor drive circuit.

[Explanation of symbols]

Reference Signs List 1 illumination optical system 2 reticle stage device 3 projection optical system 4 wafer stage device 5 reticle 6 wafer 7 reticle base 8 reticle scanning stage 9 reticle fine movement stage 10 reticle scanning drive device 11 reticle fine movement drive device 12 controller 13 wafer base 14 wafer stage X-axis drive unit 15 Wafer stage Y-axis drive unit 16 Wafer drive device 21a, 21b, 41a, 41b, 43a, 43b Air guide 22a, 22b, 42a, 42b Electromagnet 23 to 25 Actuator 26 to 28, 46, 47 Moving mirror 29 To 31, 48 to 50 Laser interferometer 44 Stepping motor 45 Ball screw 101, 201 Current control circuit 102, 208 Linear motor 103, 207 Coil 104 Mechanical relay 202 Semiconductor relay switch H 203 Charge / discharge circuit 205 Switch circuit 206 Switch box circuit 209, 211 DC-DC converter 210 Power failure detection circuit 212 Initial reset circuit 213 AND gate 214 Flip flop R1 to R5 Resistance C1 to C3 Electric double layer capacitor C4 Capacitor D1, D2 Diode SW1 to SW4 Switches L1 to L4 Coil PC1 Photocoupler PC1 Q1, Q2 MOS-FET

Continued on the front page F term (reference) 2F078 CA02 CA08 CB13 CC11 5F046 CC01 CC02 CC13 CC17 5H540 AA10 BA03 BA05 BB03 BB06 BB09 DD04 EE02 FA14 FC02 FC03 GG01 GG02 GG05 GG06 GG09 5H570 AA30 BB02 BB09 DD04 LL08 MM02 MM03 MM05 MM08 MM10

Claims (3)

[Claims] A switching unit for turning on and off a current to a coil constituting a linear motor; a first power supply unit for supplying power for operating the switching unit; and a second power supply unit for supplying a driving current for the coil. When the supply of electric power from the first power supply means and the second power supply means is stopped, in order to apply a dynamic brake to the linear motor, the power supply means is closed including the coil and the switching means. A short-circuit unit that constitutes a circuit; charged when the first power supply unit is supplying power, and at least when the supply of power from the first power supply unit and the second power supply unit is stopped. Charging / discharging means for discharging so as to backup the first power supply means while applying a dynamic brake to the linear motor. Linear motor drive device according to claim. 2. The linear motor driving device according to claim 1, wherein power is supplied to another circuit of the linear motor driving device.
Power supply means, the first power supply means, the second power supply means, and when the power supply from the third power supply means is stopped and then turned on again, the third power supply means A linear motor driving device, comprising: reset signal generation means for generating an initial reset signal at power-on based on power off / on. 3. The linear motor driving device according to claim 1, wherein a stage on which the moving object is mounted, a linear motor that drives the stage to move the moving object, and the linear motor that drives the linear motor. A stage device comprising: