JP2010027790A - Motor control device of valve for semiconductor device and motor control method of valve for semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor control device for driving valve for semiconductor capable of suppressing vibration of a valve appropriately in consideration of position and acceleration of a rotor of a motor. <P>SOLUTION: This motor control device includes a motor 12 for driving a valve 3 for semiconductor device, and a control means 14 for controlling rotation of the rotor of the motor 12. The control means 14 has an acceleration measuring part 24 for measuring the acceleration, a servo circuit part 22, digitizing the position of the rotor of the motor 12, and a central processing unit 26 for processing information from the servo circuit part 22 and the acceleration measuring part 24. The central processing unit 26 controls current flowing into the motor 12 based on the information from the servo circuit part 22 to adjust the position of the rotor of the motor 12 at a target position, and further diagnoses the vibration condition of the motor 12 based on displacement of the acceleration of the rotation of the rotor of the motor 12 measured by the acceleration measuring part 24, to control the acceleration of rotation of the rotor of the motor 12 so as to be a rotating condition of an antiphase to an amplitude period of the vibration condition of the motor 12. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control device and a control method for a motor, which is a driving source for opening and closing a gate valve or the like used in a processing chamber of a semiconductor device, for example. It is about improving.

  In the manufacturing process of a semiconductor device, a gate is provided between a processing chamber and a suction pump in order to create a vacuum state in various processing chambers for performing thin film processing by CVD (chemical vapor deposition), processing such as PVD, and PVD. A valve is used. This gate valve is generally driven by a motor. In particular, in a large and heavy gate valve, the motor is driven to vibrate as the gate valve opens and closes. When this vibration is transmitted to the processing chamber, particles are scattered in the processing chamber, affecting the performance of the semiconductor device to be manufactured, and various measuring instruments such as pressure sensors are damaged, resulting in problems. Sometimes. In particular, in recent years, a high-performance motor can be used to open and close the gate valve at a high speed. Therefore, it is necessary to pay maximum attention to the influence of vibration.

  In order to suppress the vibration of the gate valve, a gate valve provided with a vibration isolation mechanism has also been proposed (see, for example, Patent Document 1). However, there is a limit to the suppression of mechanical vibration, and there are various specifications such as the size and weight of the gate valve depending on the specifications of the manufacturing equipment. In this case, it is necessary to prepare a different mechanism for each type of gate valve. In addition, since the gate valve is elastically supported, its vibration state changes in a complicated manner. For this reason, in the mechanical response, there has been a problem that it is not always possible to sufficiently achieve the suppression of vibration by appropriately responding to various manufacturing apparatuses.

In addition, the rotational state of the motor is determined by determining the rotational state of the motor from the opening / closing speed, torque, and position of the gate valve that opens and closes at high speed, and servo-controls the motor torque, speed, and position according to the rotational state. As a result, it is considered that the movement state of the gate valve can be appropriately adjusted to a preset state at all times, regardless of the type of the gate valve, to cope with various gate valves. However, the vibration of the gate valve due to the rotation of the motor cannot always be suppressed sufficiently only by controlling the speed and torque. In particular, the vibration is increased in size and weight even if the vibration is high frequency. In the case of a gate valve, low-frequency vibrations are also generated, and there is a problem that these low-frequency vibrations cannot be sufficiently suppressed only by controlling the rotation speed and torque of the motor.
JP 2001-165333 A

  In view of the above problems, the problem to be solved by the present invention is not only the control of the movement state of the gate valve by adjusting the position of the motor, but also the vibration of the gate valve, particularly a large vibration in the low frequency region. Another object of the present invention is to provide a motor control device and a motor control method for a semiconductor device valve that can be appropriately suppressed.

(1. Control device)
As a first means for solving the above problems, the present invention provides a motor control device for a semiconductor device valve comprising a motor for driving a semiconductor device valve and a control means for controlling the rotation of the motor. The control means includes a servo circuit unit (encoder) that digitizes at least the rotor position of the motor, an acceleration measurement unit (accelerometer) that measures the rotation acceleration of the motor rotor, and a servo circuit unit (encoder). And a central processing unit (DSP) that processes information from the acceleration measuring unit (accelerometer). The central processing unit (DSP) is a current that flows to the motor based on information from the servo circuit unit (encoder). To adjust the position of the rotor of the motor to a preset target position, and to the acceleration measuring unit (accelerometer) In order to diagnose the vibration state (active vibration) of the motor from the measured displacement of the rotation of the rotor of the motor, the rotation state of the motor rotor The present invention provides a motor control device for a valve for a semiconductor device, characterized by controlling the acceleration of rotation.

  According to the present invention, as a second means for solving the above-described problems, in the first solving means, the control means is integrally attached to a valve for the semiconductor device. It provides a motor control device for a valve.

  According to the present invention, as a third means for solving the above problems, in the first or second solving means, at least a part or all of the control means is integrally attached to the motor. The present invention provides a motor controller for a semiconductor device valve.

  According to the present invention, as a fourth means for solving the above-described problems, in any one of the first to third solving means, the motor is a stepping motor, and the semiconductor device valve motor is characterized in that A control device is provided.

(2. Control method)
According to another aspect of the present invention, as a fifth means for solving the above-described problem, in the motor control method for a semiconductor device valve in which the rotation of the motor that drives the semiconductor device valve is controlled by the control means, The servo circuit unit (encoder) digitizes at least the rotor position of the motor, and the acceleration measurement unit (accelerometer) of the control means measures the rotation acceleration of the motor rotor, and the servo circuit unit (encoder) and The central processing unit (DSP) that processes information from the acceleration measurement unit (accelerometer) controls the current flowing through the motor based on the information from the servo circuit unit (encoder), and presets the position of the rotor of the motor. Adjusted to the target position, and the motor measured by the acceleration measurement unit (accelerometer) Rotation acceleration of the motor rotor is controlled so that the vibration state (active vibration) of the motor is diagnosed from the displacement of the acceleration of the rotator rotation so that the rotation state has a phase opposite to the amplitude cycle of the vibration state of the motor. The present invention provides a method for controlling a motor of a valve for a semiconductor device.

  According to the present invention, as described above, not only the valve movement state is properly adjusted by the position control of the rotor of the motor, but also the vibration is greatly affected in accordance with the determined vibration state of the motor. Since the acceleration is also controlled so that the rotation state has a phase opposite to the amplitude period of the vibration, the amplitude of the vibration state can be canceled almost in real time, and the vibration can be suppressed to the minimum. There are real benefits.

  Further, according to the present invention, as described above, since the control device is integrally attached to the valve, there is an actual benefit that the vibration of the valve can be suppressed while saving space.

  Similarly, according to the present invention, as described above, basically, the control means is separated from the motor, and only a part of the control means is integrally attached to the motor. On the other hand, there is an actual benefit that the vibration of the valve can be suppressed while saving the space by attaching all the control means integrally to the motor.

  An embodiment for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 shows a motor control device 10 according to the present invention, and this motor control device 10 is, for example, not shown in FIG. It is attached to a gate valve 3 installed between a processing chamber 1 used in a semiconductor device manufacturing process and a suction pump 2 for evacuating the processing chamber 1. As shown in FIGS. 1 and 2, the motor control device 10 is integrally attached to a gate valve 3 for a semiconductor device.

  As shown in FIGS. 1 and 2, the motor control device 10 of the present invention includes a motor 12 that drives the gate valve 3 for the semiconductor device to open and close, and a control unit 14 that controls the rotation of the motor 12. I have.

  The motor 12 is not particularly limited as long as it operates appropriately for electrical control by the control means 14, but a stepping motor (pulse motor) is preferably used. Thereby, the gate valve 3 can be positioned accurately. In this stepping motor, a stator 12 and a rotor 12A (not shown) have teeth 12a (see FIG. 4) with the same number of pitches. For example, the rotor 12A on the N pole side has the S pole side. By applying a current to one of the stator windings not shown in the figure, or by applying a current in the opposite direction to the stator winding, that is, a winding for passing a current and By switching the direction of current, a stator (not shown) and the rotor 12A are attracted or repelled to each other to rotate the rotor 12A, and as shown in FIG. 2, a gate valve connected to the rotor 12A. 3 is moved.

  On the other hand, the control means 14 has a control circuit unit 16 and a controller 18 connected to the control circuit unit 16 as shown in FIG. As shown in FIG. 3, the controller 18 is used to set various parameters for control by the control circuit unit 16 and supply power to the control circuit unit 16.

  In the illustrated embodiment, as shown in FIG. 1, of the control means 14, the control circuit unit 16 is integrally attached to the motor 12, and the controller 18 is connected to the control circuit unit 16 via a cable 20. It is connected.

  As shown in FIG. 3, the control circuit unit 16 includes a servo circuit unit 22 that digitizes at least the position of the rotor 12 </ b> A of the motor 12, an acceleration measurement unit 24 that measures the rotation acceleration of the rotor 12 </ b> A of the motor 12, and And a central processing unit 26 for processing information from the servo circuit unit 22 and the acceleration measuring unit 24. The central processing unit 26 includes a digital signal processor (hereinafter referred to as DSP) 26A as shown in FIGS.

  As shown in FIGS. 3 and 4, the servo circuit unit 22 includes an encoder 22A electrically connected to the motor 12, and the encoder 22A converts the position of the rotor 12A of the motor 12 into a numerical value. The electronic information is sent to the DSP 26A, which is the central processing unit 26. The encoder 22A can digitize the position information of the rotor 12A from the rotation angle of the rotor 12A of the motor 12, for example. Not only the position of the rotor 12A but also the rotational speed, torque, etc. of the rotor 12A are digitized and sent to the DSP 26A to set the position of the rotor 12A more precisely. You can also.

  As shown in FIGS. 3 and 4, the central processing unit 26 mainly controls the current flowing through the motor 12 based on the electronic information sent from the servo circuit unit 22, thereby rotating the rotor 12 </ b> A of the motor 12. Is adjusted to a preset target position, thereby moving the gate valve 3 to an appropriate position. Specifically, the central processing unit 26 first sets the information y (t) of the position of the rotor 12A of the motor 12 digitized by the encoder 22A and the controller 18 in advance as shown in FIG. Comparing the set position information (target position information) of the rotor 12A of the motor 12 to be the set target value and the speed profile S (t) necessary for encoding the set position information calculated from the set position information; The deviation is eliminated by PID control, and the speed and torque necessary for approximating the position of the rotor 12A of the motor 12 to the set value (set position information) are calculated, and the rotor 12A uses the value to calculate the value. A signal is generated for controlling the current to the motor 12 to rotate.

  That is, the DSP 26A, which is the central processing unit 26, calculates the adjustment parameters by the proportional operation (P), the integration operation (I), and the differentiation operation (D), and eliminates the deviation of the current flowing through the motor 12 to the motor. A current control signal (Up (t): refer to FIG. 4) for generating a current value necessary for setting the position of the rotor 12A to the target position with the speed and torque of the 12 rotors 12A as appropriate values is generated. Is applied to the motor 12 via the motor drive (see FIG. 3), the position of the rotor 12A of the motor 12 can be adjusted to a preset target position. That is, feedback control by the closed loop of the position of the rotor 12A of the motor 12 is possible.

  More specifically, the arithmetic processing in the central processing unit 26 can be expressed by the following mathematical formula.

  In this equation, e (t) is a preset speed profile S (t), as shown in FIG. 4, and information y (t) of the position of the rotor 12A of the motor 12 digitized by the encoder 22A. Is calculated by the following mathematical formula.

  As a result, the current to the motor 12 is appropriately controlled, and the rotation speed and torque of the motor 12 and thus the position of the rotor 12A can be controlled, thereby moving the gate valve 3 to an appropriate position. be able to.

  Note that Up (t) in the above equation can be generalized by the following equation, where k is the sample value.

  On the other hand, as shown in FIGS. 3 and 4, the acceleration measuring unit 24 includes an acceleration meter (accelerometer) 24A electrically connected to the motor 12, and the acceleration meter 24A allows the rotor 12A of the motor 12 to be connected. Rotational acceleration (a (t): see FIG. 4) is measured, and this electronic information is sent to the DSP 26A as the central processing unit 26 as electronic information.

  In the central processing unit 26, based on the acceleration information (a (t)) of the rotor 12A of the motor 12 sent from the acceleration measuring unit 24, the vibration state (active vibration) of the motor 12 is calculated from the displacement of the acceleration. ) And the rotation acceleration of the rotor 12A of the motor 12 is controlled so that the rotation state has a phase opposite to the amplitude period of the vibration state of the motor.

  Specifically, the DSP 26A as the central processing unit 26 uses Laplace transform (S) from the displacement of the acceleration information (a (t)) from the acceleration meter 24A as the measured value, as shown in FIG. By the differential action (Kv) and the proportional action (Kg), the period of the vibration is functionalized (u (k): see FIG. 4) and predicted, and the time shift until the vibration based on the predicted value actually occurs. In consideration of (n), in the case of a certain measured value, the amplitude period in real time necessary for canceling the vibration is calculated as a function (u (k−n): see FIG. 4), and A control output value of acceleration having an opposite phase is generated as a vibration removal signal (Ua (t): see FIG. 4).

  More specifically, the arithmetic processing in the central processing unit 26 in this case can be expressed by the following mathematical formula.

  In this case, the amplitude delay value D (u (k)) is calculated by the following equation.

  As described above, negative feedback of the acceleration to the motor 12 is achieved from the output value (measured value) of the acceleration from the motor 12, and the acceleration that affects the vibration is also appropriately controlled to generate the vibration. Can be suppressed.

  Ua (t) in the above equation can be generalized and expressed by the following equation, where k is the sample value.

  In the DSP 26A, which is the central processing unit 26, Up (t) as a result of PID control (loop 1) by the servo circuit unit 22 and Ua as a result of negative feedback (loop 2) by the acceleration measurement unit 24. (T) is combined into a final output signal (M (t)) to the motor 12, and this final output signal (M (t)) is shown in FIG. 3 and FIG. The motor 12 is fed back to the motor 12 via an isolator for electrically insulating the measurement side and the output side to the motor 12 and a motor drive (see FIG. 3) for controlling constant current and rectification. Control. Thereby, not only the position adjustment of the rotor 12A of the motor 12 by the PID control but also the vibration can be suppressed by negative feedback of the acceleration of the motor 12.

  This final output value M (t) can be calculated by the following equation.

  Note that M (t) in the above equation can be generalized and expressed by the following equation, where k is the sample value.

  In this case, since the vibration generated in the current enlarged valve 3 is a vibration in a low frequency region that shakes relatively slowly, even if the acceleration is controlled to control this vibration, the frequency It does not affect the control of acceleration which is controlled due to the moving speed of the motor with completely different bands.

  In the illustrated embodiment, the control circuit unit 16 and the controller 18 of the control unit 14 are configured separately, and only the control circuit unit 16 that is a part of the control unit 14 is integrally attached to the motor 12 so that the controller 18 However, it is also possible to integrally configure the control circuit unit 16 and the controller 18 so that the entire control means 14 is integrally attached to the motor 12.

  The present invention can be applied particularly to an etching apparatus in a semiconductor device, thin film processing by CVD, PVD, and a processing chamber used for manufacturing a flat panel display.

It is a front view which shows the installation state of the motor control apparatus of this invention. 2A and 2B show a state where the motor control device of the present invention is attached to a valve. FIG. 2A is a perspective view thereof, and FIG. 2B is a schematic sectional view thereof. It is a conceptual diagram of the control means used for this invention. It is the schematic of the content of the control processing by the control means used for this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Processing chamber 2 Suction valve 3 Gate valve 10 Control apparatus 12 Motor 12A Motor rotor 12a Motor teeth 14 Control means 16 Control circuit unit 18 Controller 20 Cable 22 Servo circuit unit 22A Encoder 24 Acceleration measurement unit 24A Accelerometer 26 Central processing Part 26A DSP

Claims (5)

In a motor control device for a semiconductor device valve, comprising: a motor for driving the semiconductor device valve; and a control means for controlling the rotation of the motor. The control means digitizes at least the position of the rotor of the motor. A servo circuit unit, an acceleration measurement unit that measures acceleration of rotation of the rotor of the motor, and a central processing unit that processes information from the servo circuit unit and the acceleration measurement unit, the central processing unit, The current flowing through the motor is controlled based on information from the servo circuit unit to adjust the position of the rotor of the motor to a preset target position, and the rotation of the motor measured by the acceleration measurement unit The vibration state of the motor is diagnosed from the displacement of the acceleration of the child's rotation, and the rotation state has an opposite phase to the amplitude period of the vibration state of the motor. The motor control apparatus of a semiconductor device for valve and controls the acceleration of the rotation of the rotor of the motor. 2. The motor control device according to claim 1, wherein the motor control device is integrally attached to the semiconductor device valve. 3. The motor control device according to claim 1, wherein at least a part or all of the control means is integrally attached to the motor. Valve motor control device. 4. The motor control device according to claim 1, wherein the motor is a stepping motor. 5. In a motor control method of a valve for a semiconductor device for controlling rotation of a motor for driving a valve for a semiconductor device by a control unit, at least a position of a rotor of the motor is digitized by a servo circuit unit of the control unit, and The acceleration measurement unit of the control means measures the rotation acceleration of the rotor of the motor, and the central processing unit that processes information from the servo circuit unit and the acceleration measurement unit, based on the information from the servo circuit unit. The current flowing through the motor is controlled to adjust the position of the rotor of the motor to a preset target position, and from the displacement of the acceleration of the rotation of the rotor of the motor measured by the acceleration measuring unit, The motor state is diagnosed and the motor is rotated in the phase opposite to the amplitude period of the vibration state of the motor. Motor control method of the semiconductor device for valve and controls the acceleration of the rotation of the coater of the rotor.

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