JP2000337429A - Active vibration damping device and semiconductor exposure device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the vibration restraining function of a structure by feedback based on a speed signal of good quality by providing a vibration sensor measuring vibration of a structural member, and driving movable elements based on the output of the vibration sensor to restrain vibration of the structural member. SOLUTION: A target 5 is fitted to a movable element 2b, and a vibration sensor 7 is fitted to the target 5. A displacement sensor 6 is fixed to a bottom plate 8. The signal of the displacement sensor 6 is input to a control device and computation-processed to excite a driver, and by carrying current to the winding coils of stators 3a, 3b, to position the movable elements 2a, 2b on the fixed normal positions. By similar control, by the signal from the vibration sensor 7, movement of the movable elements 2a, 2b are damped. Further for vibration of a floor or the like, the movable elements 2a, 2b are driven based on the signal output by detecting vibration of the bottom plate 8 with the vibration sensor 9, and the drive reaction of the movable elements 2a, 2b at this time is transmitted to the floor through the bottom plate 8 to restrain vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active vibration damping device for suppressing vibration of a structure by a driving reaction force of a movable mass, that is, an active mass damper. Also, the present invention relates to a technique for removing or reducing an adverse effect of floor vibration on positioning of a semiconductor exposure apparatus and the like using the same. Further, the present invention relates to an active vibration damping device of a type using a speed sensor instead of an acceleration sensor as a vibration sensor for detecting vibration of a structure.

[0002]

2. Description of the Related Art In order to meet the demand for miniaturization of semiconductor devices, the demand for vibration environments such as a floor on which a semiconductor exposure apparatus is installed has become severe. This is because if vibrations of the floor or the like enter the semiconductor exposure apparatus, the readings of high-precision measuring instruments in the apparatus will be disturbed, the accuracy of the positioning mechanism will be degraded, and eventually the exposure accuracy will be reduced. This is because it deteriorates.

As described above, the vibration of the floor on which the semiconductor exposure apparatus is installed significantly affects the exposure accuracy and the like. First, the semiconductor exposure apparatus itself must have a function of blocking the vibration of the floor. For this purpose, the main body structure in a recent semiconductor exposure apparatus is supported by an active vibration isolator. By activating the vibration isolation device, the vibration isolation region in the high frequency band can be expanded. In addition, the floor vibration can be detected and processed appropriately to drive the actuator in the active vibration isolator supporting the main body structure, thereby canceling the penetration of the floor vibration into the main body structure. A technique called so-called floor vibration feed forward or ground motion feed forward can be applied. Furthermore, the swinging of the main body structure caused by the driving of the movable mechanism (for example, the wafer stage) in the semiconductor exposure apparatus is
This can be suppressed by appropriately processing the drive signal of the mechanism and driving the actuator in the active vibration isolation device. This is called a reaction force feed forward.

[0004]

However, even if the active vibration isolator in the semiconductor exposure apparatus described above is optimally adjusted, the penetration of the vibration of the floor into the main body structure cannot be suppressed below the specified value. On the other hand, measures to reduce the vibration will be taken. More specifically, a structural member such as a beam forming a floor is reinforced, or concrete is poured into a beam forming a floor or the like to increase the mass of the floor and provide attenuation.

However, floor reinforcement work disturbs a clean environment in a clean room in which a semiconductor exposure apparatus is installed. Therefore, it is not realistic to apply floor reinforcement work to a clean room during production activities.

Nothing is more troublesome than the problems caused by vibrations of the floor that are discovered after installing expensive and heavy semiconductor exposure equipment. It would be desirable to be able to deal with this by changing the parameters of the active anti-vibration device in the semiconductor exposure apparatus, for example. However, if the performance is not sufficient, work must be performed to reduce floor vibration. However, it is very difficult to actually carry out floor reinforcement work.

The present invention addresses such a situation. That is, for example, it is difficult to remove or reduce the influence of floor vibration on the vibration isolator used in an apparatus such as a semiconductor exposure apparatus or the like, or on floors and other components that are frequently vibrated. In the case where it is difficult to perform reinforcement work on the equipment itself, the adverse effect of the vibration of the floor and other components on the positioning mechanism of the equipment will be eliminated or reduced by using the active vibration damping device. is there.

Conventionally, in the field of active vibration control for a structure, an acceleration sensor has been used to detect vibration. Then, the actuator is driven based on a signal obtained by arithmetically processing the output of the sensor. This calculation using the acceleration sensor required integration calculation processing. However, when performing the integration operation, filtering must be used in combination to prevent drift in the low frequency range of the acceleration sensor. Therefore, the operation process has some complexity. Then, the performance of the feedback system is deteriorated due to the filtering process.

Therefore, secondly, the present invention proposes an application for promoting the use of a speed sensor. Specifically, the present invention provides an active vibration damping device having improved vibration suppression capability of a structure by feedback based on a high-quality speed signal.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and is directed to a clean room floor or the like on which a controlled device such as a semiconductor exposure apparatus is mounted. This is an active vibration damping device that is installed at a site where the influence of vibration is remarkable or on a floor close to a device to be damped such as a semiconductor exposure apparatus. This active vibration damping device has characteristics of small size and large thrust.

That is, an active vibration damping device according to the present invention is a vibration damping device for suppressing vibration of a structural member by a driving reaction force of a mover, comprising a measurement sensor for measuring the vibration of the structural member. The vibration of the structural member is suppressed by driving the mover based on the output. Here, the mover can be driven by a linear motor. Further, the vibration sensor may be an acceleration sensor. A displacement sensor that measures the moving distance of the mover, a vibration sensor that is separate from the vibration sensor and measures the vibration of the mover, and is based on an output of the vibration sensor that measures the vibration of the mover. The drive control for the vibration control is performed, the position of the mover is controlled based on the output of the displacement sensor, and the vibration control of the structural member is performed based on the output of the measurement sensor that measures the vibration of the structural member. Drive control can be performed.

Further, the vibration sensor may be a speed sensor. Here, a displacement sensor that measures the moving distance of the mover, and a speed sensor that is separate from the speed sensor and measures the vibration of the mover, the output of the speed sensor that measures the vibration of the mover Performing drive control for the vibration suppression based on the output of the displacement sensor, controlling the position of the mover, and controlling the vibration suppression based on the output of a measurement sensor that measures the vibration of the structural member. Drive control can be performed. Further, the drive control for the vibration suppression can be performed using a signal obtained by multiplying the output of the speed sensor by a gain.

Further, a plurality of the movers can be provided. Further, the mover can swing at a predetermined frequency. The mover can be driven in a vertical direction. The mover can drive the mover in synchronization with the operation of the exposure apparatus.

In the exposure apparatus of the present invention, the above-mentioned vibration damping device is
It is provided in the exposure apparatus. Here, the above-mentioned vibration damping device may be provided in the vicinity of the stage or in a constituent member of the exposure apparatus. Further, the above-described vibration damping device can be provided on a floor or a structural member forming the floor.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS On the other hand, in recent years, in the field of machine motion control, control using the output of an acceleration sensor has become popular. For example, an acceleration sensor is used as an essential component in suspension control aimed at improving the riding comfort of a vehicle, vibration control of a structure using an active vibration damping device (commonly referred to as an active mass damper), and the like. . This is because a highly sensitive and small acceleration sensor is easily available and can be easily mounted on a control target.

Here, the identity of the manipulated variable applied to the control target by feeding back the output of the acceleration sensor will be considered. It can be seen that in most cases, an operation amount as damping is generated. For example, in the case of vehicle suspension control, skyhook damping is applied to a resonance peak to collapse the resonance peak. Similarly, in an active vibration damping device, it is common to drive an inertial mass with an electromagnetic motor such as a linear motor. However, a speed signal is generated by integrating the output of an acceleration sensor to a first order, and the speed signal is generated. The linear motor is driven based on the signal. That is, the operation amount of the speed term is generated by the linear motor. That is, in each case, the damping force, that is, the speed term force is obtained by feeding back the output of the acceleration sensor.

As described above, in most cases, the acceleration sensor that is frequently used in the motion control of a machine is used to give an operation amount as damping to a control target. If an operation amount is generated as damping, it cannot be said that there is essentially no necessity to use the outputs of acceleration sensors having different dimensions. Nevertheless, the reason for using an acceleration sensor in the field of machine control is that it is believed that this sensor is readily available and has high vibration detection resolution. That is, in the field of motion control, it has become common sense to use an acceleration sensor, and when attempting to control vibration, the acceleration sensor is mounted without any hesitation.

However, low-frequency acceleration in the field of mechanical vibration is extremely small, and a signal in this frequency region cannot be detected by an acceleration sensor. The true signal is buried in the electrical noise, and the signal actually output becomes a drift component. In view of such a property of the acceleration sensor, the speed sensor outputs a signal of a dimension obtained by integrating the acceleration by the first order, so that vibration in a low frequency range can be detected with high sensitivity in principle.

Hitherto, since the characteristics of the speed sensor from the above viewpoints have not been recognized, it has not been widely used as a general-purpose sensor. A remarkable effect is recognized in the use of the speed sensor, and if this use is promoted, it will be an easily available general-purpose sensor like the acceleration sensor. At present, there is a speed sensor known by the name of a geophone sensor, and a servo speed sensor that operates on exactly the same principle as a servo acceleration sensor. However, as mentioned above, the presence of these speed sensors is not a widely known situation and, therefore, is not designed for use in controlling machine vibration. As described above, it is necessary to design the structure and electric of the speed sensor so as to meet the vibration control of the machine.

In recent years, active mass dampers have been increasingly mounted on high-rise buildings and large bridges in order to suppress shaking. In the case of a high-rise building, the vibration of the high-rise building is detected by a vibration sensor, and the movable mass provided on the top floor of the same building is forcibly rocked in the direction opposite to the vibration of the high-rise building in accordance with the detection output. , Which suppresses the shaking of high-rise buildings.

As described above, the application of the active mass damper to a high-rise building or a bridge is in progress, but there is no example in which the active mass damper is used to reduce the vibration of the floor on which the semiconductor exposure apparatus is installed. This is because it was difficult to think that vibration of a large area floor on which the semiconductor exposure apparatus was installed could be suppressed by swinging the active mass damper.

However, if an active mass damper (hereinafter referred to as an active vibration damping device) having a small size and a large thrust characteristic can be provided, it is also necessary to suppress vibration of a floor or the like on which a semiconductor exposure apparatus is installed. It can be used.

First, the devised small and large thrust active vibration damping device will be described. Secondly, some structures of the active vibration damping device having improved thrust while maintaining small size are provided. Then, an operation method for coping with lack of lubrication that occurs when the active vibration damping device is operated for a long time is provided. Lastly, a configuration in which an active vibration damping device is applied to suppress a vibration that enters a semiconductor exposure apparatus which is a damped device will be described.

[0024]

FIG. 1 is a schematic view of an active vibration damping device 1 according to an embodiment of the present invention. In FIG. 1, 2a and 3a are a pair of flat linear motors, and 2b and 3b are also a pair of flat linear motors. Here, 2a and 2b are movers having permanent magnets, and 3a and 3b are stators having winding coils. The movers 2a and 2b are rigidly connected via a connecting plate 4, and when current is applied to the winding coils of the stators 3a and 3b, the movers 2a and 2b are simultaneously moved in the vertical direction. The reason why the movers 2a and 2 are combined via the connecting plate 4 to form an integral mover is to obtain a large thrust and to increase the weight of the mover. Reference numeral 5 denotes a target attached to the mover 2b, which measures the moving distance of the movers 2a, 2b by measuring the displacement sensor 6.
A vibration sensor 7 for detecting the vertical acceleration of the movers 2a and 2b is attached to the target 5, and the output is used for stabilizing the movement characteristics of the mover. The vibration sensor 9 attached to the bottom plate 8 measures the vibration of the floor or the like that comes into rigid contact with the bottom plate 8. Here, an acceleration sensor or a speed sensor can be used as the vibration sensor,
A speed sensor is preferred as described below.

FIG. 2 shows a schematic configuration of a control system for the active vibration damping device 1. The position of the movers 2a and 2b in the vertical direction is obtained by measuring the detection surface of the target 5 attached to the mover by the displacement sensor 6 fixed to the bottom plate 8, and this output is input to the control device 10, This is a feedback signal for localizing 2a, 2b at a predetermined position in the vertical direction. That is, by inputting a signal from the displacement sensor 6 to the control device 10 and performing an appropriate operation, the drivers 11a and 11b are excited and current is supplied to the winding coils 12a and 12b of the stators 3a and 3b. As a result, the movers 2a and 2b are located at predetermined positions. At this time, although a mechanism for guiding the movers 2a and 2b in the vertical direction is not shown in FIG. 1, for example, a guide rail for rolling guide with low friction in the moving direction can be used. When such a guide mechanism is used, the damping performance is inferior for positioning the movers 2a and 2b at desired positions. Therefore, the signal of the vibration sensor 7 that moves integrally with the movers 2a and 2b is input to the control device 10. This signal is sent to the control unit 1
0, the signals are appropriately processed in the drivers 11a and 11b for supplying current to the winding coils of the stators 3a and 3b.
b is excited, but acts so as to add diminution (damping) to the movement of the movers 2a and 2b. That is, by inputting the output signals of the displacement sensor 6 and the vibration sensor 7 to the control device 10, the movers 2a and 2b can be stably localized at predetermined positions in the vertical direction.

The vibration of the floor or the like is detected by the vibration sensor 9 of the bottom plate 8 of the active vibration damping device 1 in contact with the floor. This output signal is also input to the control device 10. In the control device 10, the movable element 2 is moved according to the vibration of the bottom plate 8.
a and 2b are driven, and movers 2a and 2 generated at this time are driven.
The driving reaction force of b is transmitted to the floor or the like via the bottom plate 8. After all, the vibration of the floor or the like in contact with the bottom plate 8 is
This is suppressed by the driving reaction forces a and 2b.

Here, in the active vibration damping device 1 shown in FIG. 1, two pairs of linear motors in the form of a flat plate comprising the mover 2 and the stator 3 are used. The reason for this is to increase the driving thrust and the mass of the mover in order to use the active vibration damping device for the purpose of suppressing vibration of the floor or the like. Therefore, if the drive thrust and the mass of the mover are increased, the vibration of a larger structure can be suppressed. At this time, it is preferable from the viewpoints of cost, reliability, and space to increase the driving thrust and the mass by using a plurality of linear motors that have already been used without newly designing a linear motor.

FIGS. 3A to 3E show examples of the structure of an active vibration damping device using a plurality of linear motors to increase the driving thrust and the mass. The figure shows the mechanical connection for parallel driving of the linear motor. That is, it is a schematic view of the active vibration damping device 1 in which the thrust and the movable mass are increased by connecting plate-shaped linear motors in parallel, as viewed from above.

FIG. 3A shows the active vibration damping device shown in FIG. A case where two linear motors are connected by using a connecting plate 4 is shown. FIG. 2B shows a case where three flat linear motors are connected to three side surfaces of a substantially triangular connecting member 4b, and FIG. 2C shows three linear motors connected to an inverted T-shaped connecting member 4c. (D) shows a case where four flat plate-like linear motors are connected to the side surface of a substantially square connecting member 4d, and FIG. (E) shows a case where a substantially H-shaped connecting member 4e is connected. Shows a case in which four pairs of linear motors are connected.

As the active vibration damping device shown in FIGS. 3A to 3E is improved, the driving thrust is improved and the mass of the movable portion is increased. In the case of FIG. 1, for example, the mass of the movable portion is largely determined by the masses of the movers 2a and 2b having permanent magnets. However, the additional mass can be added to the side surface of the mover 2 to increase the mass as the mover. In addition, for example, FIG.
In the case of (1), a weight for increasing the mass as the mover can be added to the center of the connecting members 4b and 4d.

Here, as a guide mechanism for moving the movers 2a and 2b in the vertical direction, for example, a guide rail using a circulating ball is used. It should be noted that the movable elements 2a and 2b are positioned at specific positions in the vertical direction, and the movable elements 2a and 2b are moved up and down in the vicinity of the specific positions according to the vibration of the floor. This amplitude is very small. Therefore, the lubrication of the guide rails is depleted due to the minute vibrations of the movers 2a and 2b at the same place, and the mover cannot move smoothly on the guide rails after a long operation. Cause the problem. In order to address such a problem, the present invention provides two solutions.

First, one is that the operation of the active vibration damping device 1 is
This is a case in which the exposure is performed independently of a semiconductor exposure apparatus (stepper or scanner), that is, in a stand-alone manner. Attention is paid to the fact that the drive suppression by the active vibration damping device 1 is normally performed for a floor vibration mode of several tens Hz. That is, the movers 2a and 2b are rocked at a frequency sufficiently lower than the vibration frequency. The swing of the movers 2a and 2b at a low frequency does not affect the vibration suppression by the active vibration damping device 1. The mover 2a in the active vibration damping device 1,
This is because the equilibrium position of 2b changes only very slowly. By giving such a movement to the movers 2a and 2b, the problem of insufficient lubrication of the guide rail can be avoided.

The second solution is to synchronize the active vibration damping device 1 with the operation of a stepper or a scanner.
More specifically, in the case of the stepper, a step period of an appropriate time interval is captured, and during this period, the movers 2a and 2b of the active vibration damping device are temporarily seated, or a large amplitude is set around the equilibrium position. Force to move. In the case of a scanner as well, an appropriate period not related to exposure, such as during a step period, is captured, and the movers 2a and 2b in the active vibration damping device 1 are seated or forcedly moved with a large amplitude around the equilibrium position. . By giving such an operation to the movers 2a and 2b, the guide rail is appropriately lubricated. As a result, even if the movers 2a and 2b continuously vibrate minutely around the same place, they are worn out due to lack of lubrication. Act so as not to cause.

Hereinafter, a configuration in which the above-described active vibration damping device 1 is installed on a floor or the like to remove or reduce the influence of vibration of the floor on the semiconductor exposure apparatus on positioning or the like will be described with reference to FIGS. I do.

[Embodiment 1] FIG.
1 shows a state in which the active vibration damping device 1 of the present invention is arranged in the vicinity of. It is assumed that vibrations entering from the outside exist on the stage base 14 on which the wafer stage 13 is mounted. For example, it is assumed that the vibrations are superimposed on the positioning waveform mainly in the vertical direction of the wafer stage 13 and deteriorate the positioning accuracy. In this case, if the vibration superimposed on the stage base 14 can be suppressed, the vibration superimposed on the wafer stage 13 can also be suppressed. Thus, the positioning accuracy can be improved. Therefore, as shown in FIG. 4, the active vibration damping device 1 is installed near the wafer stage 13, for example, on the stage base 14.

[Embodiment 2] FIG. 5 shows a configuration in which an active vibration damping device 1 is arranged directly on a floor on which a semiconductor exposure apparatus is installed.
In FIG. 1, reference numeral 15 denotes a grating that forms a floor in a clean room where the semiconductor exposure apparatus 16 is installed. The grating 15 is placed and fixed on the upper surface of the beam 17. As illustrated, the active vibration damping device 1 is installed on a floor near the semiconductor exposure device 16.
By suppressing the vibration of the floor portion, the vibration of the floor is prevented from entering the semiconductor exposure apparatus 16.
Of course, in FIG. 5, only one active damping device 1 is used for the semiconductor exposure device 16, but a plurality of active damping devices may be actually used. By arranging a plurality of the active vibration damping devices around the semiconductor exposure device 16, floor vibration for installing the exposure device can be reduced and a favorable environment can be provided.

[Embodiment 3] FIG.
A configuration in which the active vibration damping device 1 is installed is shown below. In the figure, a grating 15 is placed and fixed on the upper surface of a beam 17. Reference numeral 18 denotes a girder supporting a load (for example, a semiconductor exposure apparatus) on the grating 15 together with the beam 17. Here, the main vibration on the grating 15 constituting the floor of the clean room is often present on the girder 18 forming the framework of the building. That is, the girder 18 has the original vibration that causes the grating 15 to vibrate. Therefore, if the vibration at this portion can be suppressed, the vibration on the grating 15 can also be suppressed.

Therefore, the active vibration damping device 1 is fixed on the girder 18 as a structural member forming the floor by using an appropriate fixing jig 19. Fortunately, there is a space between the grading 15 and the girder 18 where the active vibration damping device 1 can be installed. As shown in FIG. 5, when the active vibration damping device 1 is installed on the floor near the semiconductor exposure device 16,
There is a high possibility that the layout flexibility of other production facilities, including, and the movement of people and things involved in production activities will be disturbed. However, the configuration shown in FIG. 6 has an advantage that this is not the case. Of course, the vibration suppression using the active vibration damping device 1 for the girder as the structural equipment is not limited to the case where only one is used as shown in FIG. Taking into account the vibration mode of the girder 18 as a structural member, the vibration of the structural member itself can be suppressed by using a plurality of active damping devices 1, which leads to a reduction in the vibration of the floor of the clean room. In addition, the vibration is prevented from entering the semiconductor exposure apparatus 16, thereby contributing to an improvement in productivity.

Next, experimental results showing the effect of vibration suppression using the active vibration damping device 1 will be described. FIG. 7 shows the spectrum of floor vibration when (A) the active vibration damping device 1 is not operated and when (B) it is operated. When the active vibration damping device 1 was not operated, the floor subjected to the test had a vibration peak of about 25 Hz as indicated by A in the figure. Vibration peaks also exist at other frequencies, but these are vibration peaks that are propagating through the floor as a transmission path, and
The vibration peak at 5 Hz has been found to be the natural vibration mode of the floor. When the active vibration damping device 1 is operated, it can be confirmed that this vibration peak is suppressed as indicated by B in the figure, and it is understood that the active vibration damping device 1 is functioning effectively.

Further, an experiment was conducted in which the active vibration damping device 1 was installed at a place different from the floor where the frequency characteristics shown in FIG. 7 were obtained, and the vibration of the floor was suppressed. FIG. 8 shows acceleration time-series signals of floor vibration when the active vibration damping device 1 is not operated and when it is operated. FIG. 3A shows a case where the active vibration damping device 1 is off.
FIG. 3B shows an acceleration time-series signal of floor vibration when the active vibration damping device is turned on. Obviously, when the active vibration damping device is turned on, the vibration of the floor near the installation of the device can be suppressed.

FIG. 1 shows an active vibration damping device 1 according to the present invention.
The vibration sensor 9 was provided near the movers 2a and 2b, that is, near the driving point. However, vibration of a portion of the movable elements 2a and 2b apart from the driving point is detected by the vibration sensor 9, and the movable elements 2a and 2b are moved in accordance with the detected output.
Driving a and 2b also belongs to the present invention. FIG.
In the active vibration damping device 1 shown in (1), the movers 2a and 2b are stably localized at the equilibrium position using the displacement sensor 6 and the vibration sensor 7. That is, the equilibrium position of the movers 2a and 2b was actively secured. However, it goes without saying that an active vibration damping device that secures the equilibrium position of the movers 2a and 2b using a passive spring or a viscous element, and a semiconductor exposure device using the same also belong to the present invention.

[Embodiment 4] FIG. 9 shows a case where an accelerometer is used as a vibration sensor in the active vibration damping device 1 of FIG.
The configuration of feedback to the active vibration damping device 1 is shown.
In the drawing, the output of the acceleration sensor 7 integrated with the movers 2a and 2b is converted into a speed signal via an integration compensator 20, and a power amplifier for supplying a current to stators 3a and 3b, which are winding coils. Is negatively fed back to the previous stage. The movement of the movers 2a and 2b is damped by the feedback loop. Next, the output of the displacement sensor 6 that measures the moving distance of the movers 2a and 2b with reference to the bottom plate 8 is input to the position controller 22. Position controller 2
Another input to 2 is a voltage to be applied to the target voltage application terminal 23, and this voltage determines the localization position of the movers 2a, 2b in the vertical direction with respect to the bottom plate 8. The position controller 22 can be composed of a comparator and a gain compensator or a P1 compensator. Here, P means proportional and 1 means integral operation. Then, a signal obtained by adding the output of the position controller 22 and the negative feedback signal of the integration compensator 20 described above is input to the power amplifier. By the neutral position stabilization control device 24 surrounded by such a broken line, the mover 2
a and 2b are stably located at the equilibrium position in the vertical direction.

The function of the neutral position stabilization control device 24 can be realized without applying feedback based on the outputs of the displacement sensor 6 and the acceleration sensor. Combining a leaf spring and a viscous element, etc.,
a and 2b may be held at the neutral position.

In order to provide a damping action to a structure (not shown) in which the movers 2 a and 2 b are rigidly in contact with the bottom plate 8, feedback based on the outputs of the integral compensator 20 and the position controller 12 is performed. Another new feedback loop is required. In response to the output of the acceleration sensor 9 mounted on the bottom plate 8, the movable elements 2 a and 2 b are oscillated, and the vibration of a structure (not shown) rigidly in contact with the bottom plate 8 due to the driving reaction force at that time is suppressed. It is a loop of. Referring to FIG.
The loop in which the output of the acceleration sensor 9 attached to the bottom plate 8 is guided to the second integration compensator 25 and the output is fed back to the previous stage of the power amplifier 21 corresponds to this.

With the configuration of the above-described control device, it is possible to swing the movers 2a and 2b around the neutral position in accordance with the vibration of the bottom plate 8 with the movers 2a and 2b positioned at the neutral position. And the structure can be damped by the driving reaction force at this time.

[Embodiment 5] FIG. 10 shows an active vibration damping device 1 using a speedometer as the vibration sensor of FIG.
The configuration of feedback to the active vibration damping device 1 is shown.
In the active vibration damping device shown in FIG. 9, generally available acceleration sensors 7, 9 are mounted. Therefore, in order to stably position the movers 2a and 2b at the neutral position, the output of the acceleration sensor 7 is converted into a speed signal through the integration compensator 20. Similarly, the output of the acceleration sensor 9 is also converted into a speed signal through the integration compensator 15. In this embodiment, the acceleration sensors 7 and 9 are replaced with velocity sensors 7V and 9V, respectively, as shown in FIG. With this replacement, the integral compensators 20 and 25 are replaced by gain compensators 20V and 25V. Speed sensor 7
V and 9V output absolute speeds, and drive power amplifier 11V using the output as it is, thereby generating an operating force as damping. That is, by feeding back the output of the speed sensor 7V via the gain compensator 20V, the movable elements 2a, 2
b is damping. The processing for the output of the displacement sensor 6 is the same as in FIG. As a result, a neutral position stabilization control device 24V in the case of using a speed sensor surrounded by a broken line by feedback using outputs of the displacement sensor 6 and the speed sensor 7V is configured. The output of the speed sensor 9V mounted on the bottom plate 8 is fed back to the front stage of the power amplifier via the gain compensator 25V, so that the movable elements 2a and 2b This gives a damping force as a damping force due to the driving reaction force.

In the active vibration damping device shown in FIG. 9, since an acceleration sensor is used, an integral operation is required to generate an operating force as damping. When this operation is realized by an analog electronic circuit, the integration time constant is determined by the capacitor and the resistor.However, when the time constant is large, a capacitor with a large capacity must be used. A problem arises in accuracy. Further, since the output of the acceleration sensor drifts in a low frequency range, a filtering process for cutting a signal in the low frequency range is also required, and this degrades the performance of the active vibration damping device. On the other hand, in the case where the integration compensators 20 and 25 are realized digitally, it is necessary to take measures such as windup, although there is not much difficulty, and some complications cannot be avoided.

On the other hand, according to the active vibration damping device of the present embodiment, the output of the speed sensors 7V and 9V may be simply multiplied by a gain and fed back, so that there is an advantage that the feedback device is simplified. . In addition, since unnecessary filtering processing in the related art is not required, there is an effect that a deterioration factor of the vibration suppression performance can be eliminated.

[Embodiment of Device Production Method] Next, an embodiment of a device production method using an exposure apparatus having the above-described active vibration damper will be described. FIG. 11 shows a micro device (a semiconductor chip such as an IC or an LSI, a liquid crystal panel, a CC)
D, thin-film magnetic head, micromachine, etc.). In step 1 (circuit design), a device pattern is designed. Step 2 is a process for making a mask on the basis of the designed pattern. On the other hand, in step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon or glass. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), an operation confirmation test of the semiconductor device manufactured in step 5 is performed.
An inspection such as a durability test is performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 12 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 1
In 5 (resist processing), a photosensitive agent is applied to the wafer. In step 16 (exposure), the circuit pattern of the mask is printed and exposed on the wafer by the exposure apparatus having the above-described active vibration damping device. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the production method of this embodiment, it is possible to produce a highly integrated device, which was conventionally difficult to produce, at low cost.

[0052]

The effects of the present invention are as follows. (1) A problem with exposure accuracy caused by vibration of a floor or the like detected after installing a semiconductor exposure apparatus can be promptly dealt with.

(2) That is, the active vibration damping device which is easy to handle is used without re-adjusting the parameters of the units in the semiconductor exposure device and without reinforcing the floor on which the semiconductor exposure device is installed. Thus, the influence on the exposure accuracy and the like can be suppressed or reduced.

(3) The vibration state of the floor on which the semiconductor exposure apparatus is installed changes when a new apparatus is loaded. Even in such a situation, it is possible to cope with fluctuations in the vibration environment by changing the installation location and the number of active damping devices or changing the adjustment of the active damping devices. The effects of the present invention by using a speedometer as a speed sensor are as follows.

(4) When the vibration of a structure to be suppressed is measured by an acceleration sensor, this output is integrated into the first order and converted into a speed signal to drive the inertial mass in the active vibration damping device. However, if a speed sensor is used, it is not necessary to include an integral in the feedback calculation processing. That is, since the output of the speed sensor may be directly fed back, the present invention has an effect that the feedback device can be simplified.

(5) In connection with the above (4), a filtering process other than the main integration compensation for the output of the acceleration sensor is also used, so that the filtering process has a limit on the vibration suppression effect. That is, if the gain is increased to enhance the vibration suppression performance, oscillation is likely to occur. However,
The use of the speed sensor eliminates the need for the filtering process, and makes it possible to increase the gain for vibration suppression. That is, there is an effect that the vibration damping effect can be enhanced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an active vibration damping device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a control system of the active vibration damping device.

FIG. 3 is a diagram showing mechanical connections for parallel driving. (A) 2 links (b) 3 links (c) Another 3 links (d) 4 links (e) Another 4 links

FIG. 4 is a diagram showing an active vibration damping device installed near a wafer stage according to one embodiment of the present invention.

FIG. 5 is a diagram showing an active vibration damping device placed on a floor on which a semiconductor exposure apparatus according to an embodiment of the present invention is installed.

FIG. 6 is a diagram showing a mounting diagram of the active vibration damping device below the grating according to one embodiment of the present invention.

FIG. 7 is a diagram showing a spectrum of floor vibration.

FIG. 8 is a diagram showing an acceleration time-series signal of floor vibration. (A) When the active vibration suppression device is off (b) When the active vibration suppression device is on

FIG. 9 is a diagram showing a configuration of feedback to the active vibration damping device according to one embodiment of the present invention.

FIG. 10 is a diagram showing a configuration of feedback for an active vibration damping device according to one embodiment of the present invention.

FIG. 11 is a diagram showing a flow of manufacturing a micro device.

FIG. 12 is a diagram showing a detailed flow of a wafer process.

[Explanation of symbols]

1: Active vibration damping device, 2a, 2b: mover having permanent magnet, 3a, 3b: stator having winding coil, 4: connecting plate, 5: target, 6: displacement sensor, 7: vibration sensor, 7V : Speed sensor, 8: bottom plate, 9: vibration sensor, 9
V: speed sensor, 10: control device, 11a, 11b: driver, 12a, 12b: winding coil, 13: wafer stage, 14: stage base, 15: grating,
16: semiconductor exposure apparatus, 17: beam, 18: beam, 19:
Fixing jig, 20: integral compensator, 20V: gain compensator,
21: Power amplifier, 22: Position controller, 23: Target voltage application terminal, 24: Neutral position stabilization controller, 24V: Neutral position stabilization controller using speed sensor, 25: Integral compensator, 25V: Gain Compensator.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takehiko Mayama 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 3J048 AA06 AB08 AB09 AB11 AD03 BE09 BF09 CB19 EA07 5F046 AA23

Claims (15)

[Claims] 1. A vibration damping device for suppressing vibration of a structural member by a driving reaction force of a mover, comprising a measurement sensor for measuring the vibration of the structural member, and driving the mover based on an output of the vibration sensor. A vibration damping device characterized by suppressing vibration of the structural member. 2. The vibration damping device according to claim 1, wherein the movable element is driven by a linear motor. 3. The vibration damping device according to claim 1, wherein the vibration sensor is an acceleration sensor. 4. A vibration sensor for measuring the movement of the mover, the displacement sensor for measuring the movement distance of the mover, and a vibration sensor separate from the vibration sensor for measuring the vibration of the mover. Performing drive control for the vibration suppression based on the output of the displacement sensor; controlling the position of the movable element based on the output of the displacement sensor; and controlling the vibration of the structural member based on the output of a measurement sensor. The vibration damping device according to any one of claims 1 to 3, wherein drive control for vibration damping is performed. 5. The vibration damping device according to claim 1, wherein the vibration sensor is a speed sensor. 6. A speed sensor for measuring a vibration of the mover, comprising: a displacement sensor for measuring a moving distance of the mover; and a speed sensor for measuring a vibration of the mover, which is separate from the speed sensor. Performing drive control for the vibration suppression based on the output of the displacement sensor; controlling the position of the mover based on the output of the displacement sensor; and controlling the vibration based on the output of a measurement sensor that measures the vibration of the structural member. 6. The vibration damping device according to claim 5, wherein drive control for vibration is performed. 7. The vibration damping device according to claim 6, wherein the drive control for the vibration damping is performed using a signal obtained by multiplying the output of the speed sensor by a gain. 8. The vibration damping device according to claim 1, comprising a plurality of said movers. 9. The vibration damping device according to claim 1, wherein the mover swings at a predetermined frequency. 10. The vibration damping device according to claim 1, wherein the mover is driven in a vertical direction. 11. The apparatus according to claim 1, wherein the mover drives the mover in synchronization with the operation of the exposure apparatus.
The vibration damping device according to any one of claims 10 to 10. 12. An exposure apparatus, wherein the vibration damping apparatus according to claim 1 is provided in an exposure apparatus. 13. An exposure apparatus, wherein the vibration damping device according to claim 1 is provided near a stage or on a component of the exposure apparatus. 14. An exposure apparatus, wherein the vibration damping device according to claim 1 is provided on a floor or a structural member forming the floor. 15. A device manufacturing method, comprising manufacturing a device using the exposure apparatus according to claim 12.