JP4674422B2 - Apparatus and pump system with multiple turbomolecular pumps - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus including a plurality of turbo molecular pumps such as a semiconductor manufacturing apparatus and a pump system including a plurality of turbo molecular pumps.
[0002]
[Prior art]
In a semiconductor manufacturing apparatus, a turbo molecular pump is often used as a vacuum pump. However, since a semiconductor manufacturing apparatus generally includes a plurality of vacuum chambers, a plurality of turbo molecular pumps are also used. When the apparatus is activated, all of the plurality of turbo molecular pumps are activated simultaneously. That is, a start signal is transmitted from the main controller of the semiconductor manufacturing apparatus to the drive controller of each turbo molecular pump, and the turbo molecular pumps start rotating the rotor all at once.
[0003]
FIG. 10 shows the relationship between the operating state of the turbo molecular pump, the rotational speed, and the power consumption. The power consumption of the turbo molecular pump during the start-up operation increases as the rotor rotational speed increases, and peaks immediately before the rated rotational speed is reached. During rated operation, since the rotor speed is controlled to be constant, the power consumption is considerably smaller than the peak at startup. Therefore, the power supply unit of the drive control device is designed in consideration of the peak power immediately before the rated rotational speed.
[0004]
[Problems to be solved by the invention]
By the way, when multiple turbo molecular pumps of the same specification are used in a semiconductor manufacturing apparatus, since each turbo molecular pump is started all at once as described above, the peak immediately before the rated rotational speed also occurs almost simultaneously. become. Since AC power is supplied to the drive control device via the power supply device of the semiconductor manufacturing device, the power supply device of the semiconductor manufacturing device has to be designed in consideration of the peak power when the turbo molecular pump is started. For example, if the peak power of the turbo molecular pump is 1 kW and the number thereof is five, the capacity of the apparatus-side power supply device is set to be larger than 5 kW in consideration of power consumption other than the pump. For this reason, the power supply device has been increased in size and increased in cost. In addition, with regard to the power equipment in which the semiconductor manufacturing apparatus is installed, it is necessary to increase the capacity of the wiring and the like in accordance with the peak power.
[0005]
The objective of this invention is providing the apparatus and pump system which can reduce the maximum power consumption at the time of starting in the apparatus and pump system provided with several turbo-molecular pumps.
[0006]
[Means for Solving the Problems]
A description will be given in association with FIGS. 1, 2 and 9 showing an embodiment of the invention.
(1) Referring to FIGS. 1 and 2, the apparatus according to the first aspect of the present invention has a power consumption peak generation time at the start of a plurality of turbo molecular pumps TMP1 to TMP7 for each turbo molecular pump TMP1 to TMP7. The above-described object is achieved by providing a control device 24 for starting the turbo molecular pumps TMP1 to TMP7 simultaneously and starting the turbo molecular pumps TMP1 to TMP7 so as to be different from each other. .
(2) Referring to FIG. 9, the invention of claim 2 is provided with a plurality of turbo molecular pumps 10 and a plurality of turbo molecular pumps 10, and a plurality of turbo molecular pumps 10 for driving and controlling the corresponding turbo molecular pumps 10. Drive device 30, power conversion unit 31 that converts AC power into DC power, and supplies the converted DC power to each of the plurality of drive devices 30, and power consumption peak occurrence times at the time of activation of the plurality of turbo molecular pumps 10 so each different for each turbo-molecular pump 10, to achieve the above object by starting operation time of each turbo-molecular pump 10 has a control unit 32 which controls each different, the.
[0007]
In the section of means for solving the above problems, the drawings of the embodiments of the invention are used for easy understanding of the present invention. However, the present invention is not limited to the embodiments of the invention. Absent.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
-First embodiment-
FIG. 1 is a plan view showing an example of the configuration of a semiconductor manufacturing apparatus. In the semiconductor manufacturing apparatus 1 shown in FIG. 1, four process chambers 2 to 5, a load chamber 6, and an unload chamber 7 are provided so as to surround the transfer chamber 8. In each of the chambers 2 to 5, the load chamber 6, the unload chamber 7, and the transfer chamber 8, turbo molecular pumps TMP1 to TMP7 are provided. Usually, large turbo molecular pumps are used for exhausting the process chambers 2 to 5, and small turbo molecular pumps are used for the load chamber 6, the unload chamber 7 and the transfer chamber 8. In the following description, for the sake of simplicity, the turbo molecular pumps TMP1 to TMP7 are all described as being turbomolecular pumps having the same specifications. A substrate transfer arm (not shown) is provided in the transfer chamber 8, and the substrate (silicon wafer substrate, liquid crystal panel substrate, etc.) is transferred to the chambers 2 to 5, the load chamber 6, and the unload chamber 7 by this arm. Be transported.
[0009]
The turbo molecular pumps TMP1 to TMP7 shown in FIG. 1 are each composed of a pump body 10 and a power supply device 11 as shown in FIG. That is, the semiconductor manufacturing apparatus 1 is provided with seven sets of the pump main body 10 and the power supply apparatus 11 shown in FIG. 2, and each power supply apparatus 11 is controlled by the controller 22 of the semiconductor manufacturing apparatus 1. The pump body 10 is provided with a rotor shaft 12 to which rotating blades are attached. The turbo molecular pump shown in FIG. 2 is a magnetic bearing type turbo molecular pump, and the rotor shaft 12 is supported in a non-contact manner by a magnetic bearing 13. The gap position of the rotor shaft 12 is detected by the gap sensor 14. The magnetic bearing control circuit 15 controls the excitation current of the magnetic bearing 13 based on the detection result of the gap sensor 14.
[0010]
The power conversion unit 16 of the power supply device 11 is an insulating AC / DC converter, converts AC power input from the power supply unit 23 of the controller 22 into DC power, and supplies the DC power to the inverter unit 17. The inverter unit 17 is provided with six sets of transistors 18 and diodes 19 and a drive control circuit 20 for driving the transistors 18. The high frequency motor 21 that rotationally drives the rotor shaft 12 is driven by AC power output from the inverter unit 17. The levitation / suspension of the rotor shaft 12 and the start / stop of the motor 21 by the magnetic bearing 13 are controlled by an on / off signal from the control unit 24. A brake resistor 25 is used when the motor is stopped. The transistor 26 is normally turned off. As will be described later, the transistor 26 is turned on and a regenerative current is supplied to the brake resistor 25 during a regenerative braking operation.
[0011]
FIG. 3 is a diagram illustrating a control example of the turbo molecular pumps TMP1 to TMP7 by the controller 22. FIGS. 3A to 3C show changes in the rotational speed and power consumption from start to stop for the turbo molecular pumps TMP1 to TMP3 among the seven sets of turbo molecular pumps TMP1 to TMP7. . FIG. 3D shows a change in the total power consumption of the three turbo molecular pumps TMP1 to TMP3. As shown in FIGS. 3A to 3C, the control patterns of the three turbo molecular pumps TMP1 to TMP3 are all the same, but the activation start times are different.
[0012]
First, the control pattern of the turbo molecular pump TMP1 will be described with reference to FIG. t11 is the time at which the start signal is transmitted from the controller 22 of the semiconductor manufacturing apparatus 1 to the turbo molecular pump TMP1, and upon receiving the start signal, the turbo molecular pump TMP starts the start operation (acceleration of rotor rotation). After time t11, the power consumption increases as the rotational speed increases and reaches peak P1 (power consumption W1 (kW)) immediately before time t12 when the rated rotational speed N ₀ (rpm) is reached. From time t12 to t13 represents the rated operation, and the rotor rotational speed is kept constant (N ₀ ). Therefore, since it is only necessary to maintain the rotation when shifting to the rated operation, the power consumption is reduced to W2 (<W1).
[0013]
Thereafter, the stop signal is received at time t13, and the stop operation is started. In this stop operation, the switching phase of the transistor 18 is reversed by the drive control circuit 20, and the rotational energy of the motor 21 is converted into electric energy and regenerated. When the transistor 26 in FIG. 2 is turned on during the regenerative braking operation, a regenerative current flows through the brake resistor 25 and the rotational energy is released as heat. In the example shown in FIG. 3A, the regenerative brake is operated from time t13 to time t14. As a result, power consumption for deceleration is reduced from time t13 to time t14. Thereafter, the rotor rotation stops at time t15.
[0014]
In the example of FIG. 2, by providing the diode 27, the current from the power conversion unit 16 is normally supplied to the magnetic bearing control circuit 15, but the voltage rises during the braking operation, so that the power due to the regenerative current is reduced. This is supplied to the magnetic bearing control circuit 15.
[0015]
The turbo molecular pumps TMP2 and TMP3 are controlled in exactly the same pattern. However, the turbo molecular pump TMP2 starts its operation at time t21, and the turbo molecular pump TMP3 starts its operation at time t31. The timing of the start start times t21 and t31 with respect to the time t11 is such that the power consumption peaks P1 to P3 of the turbo molecular pumps TMP1 to TMP3 are shifted to the left and right in the figure, and the total power consumption peak is suppressed as shown in FIG. To be set. In the example shown in FIG. 3, the turbo molecular pumps TMP1 to TMP3 are pumps of the same specification, and their starting operation times Δt are all equal, and Δt = t12−t11 = t22−t21 = t32−t31. In addition, since the start-up operation time may be different if the specifications of the turbo molecular pumps TMP1 to TMP3 are different, in such a case, the turbo molecular pumps TMP1 to TMP1 to be appropriately shifted so that the generation times of the peaks P1 to P3 are appropriately shifted. You can set the start time of TMP3.
[0016]
FIG. 4 compares the total power consumption of the turbo molecular pumps TMP1 to TMP3 with the conventional case. The solid line represents the case of this embodiment, and the broken line represents the power consumption when three units are started simultaneously. ing. The peak value W4 at time t12 in the case of simultaneous activation of three units is three times the power consumption value W1 of the peak P1 shown in FIG. On the other hand, in the present embodiment, since the peaks P1 to P3 are shifted as shown in FIGS. 3A to 3C, the total power consumption shown in FIG. 3D and FIG. The value W3 of the peak P4 ′ is W3 <W4. In addition, although peak 4 'is flat as shown in FIG.3 (d) and FIG. 4, such a case is also called a peak.
[0017]
In the above description, the turbo molecular pumps TMP1 to TMP3 have been described. However, the turbo molecular pumps TMP4 to TMP7 in FIG. 1 are also considered in the same manner, and the start start times are shifted in the order of the turbo molecular pumps TMP1 to TMP7. As a result, the startup peaks of the turbo molecular pumps TMP1 to TMP7 are shifted from each other, and the magnitude of the power consumption peak can be reduced as compared with the conventional case.
[0018]
"Modification 1"
FIG. 5 is a diagram showing a modification of the first embodiment, and (a) to (c) show the relationship between the operating state of the turbo molecular pumps TMP1 to TMP3, the rotational speed, and the power consumption. . In the example shown in FIG. 3 described above, the peak value of the total power consumption is reduced by shifting the startup start times of the turbo molecular pumps TMP1 to TMP7 from each other. On the other hand, in this modification, the starting operation time Δt ′ = t11−t42 is made longer than the starting operation time Δt = t11−t12 in the case of FIG. I did it. As shown in FIG. 5A, the value W5 of the peak P5 becomes smaller than the peak value W1 in the case of FIG.
[0019]
Since the turbo molecular pumps TMP2 and TMP3 perform the same start-up control as the turbo molecular pump TMP1, as shown by the solid line in FIG. 6, the total power consumption W6 (= 3 × W5) of the three units is shown by the broken line in FIG. It becomes smaller than the power W4 (power consumption when the control as shown in FIG. 3A is performed). Since the control other than the start operation is the same as in the case of FIG. 3A, the power consumption during rated operation and during stop is the same in both cases. Note that the start-up operation time of the turbo molecular pumps TMP4 to TMP7 is also increased similarly to the turbo molecular pumps TMP1 to TMP3. Normally, in the turbo molecular pump, the starting operation time is set in the drive control circuit 20 of FIG. Therefore, the activation operation time set in the drive control circuit 20 of each power supply device 11 may be changed according to the number of pumps mounted in the device 1. This change may be set from the controller 22 side of the apparatus 1.
[0020]
"Modification 2"
FIG. 7 is a diagram showing a second modification, which is the same as FIG. In the second modification, all the turbo molecular pumps TMP1 to TMP7 are started at the same time when the apparatus is started, but the starting operation times are different from each other. FIG. 7 shows the turbo molecular pumps TMP1 to TMP3. The turbo molecular pumps TMP1 to TMP3 are started to start at time t11. However, the starting operation times Δt1, Δt2, and Δt3 of the turbo molecular pumps TMP1 to TMP3 were set so that Δt1 <Δt2 <Δt3. Therefore, the generation times of the peaks P1, P7, and P8 of the turbo molecular pumps TMP1 to TMP3 are shifted, and the power consumption W7 and W8 of the peaks P7 and P8 are smaller than the power consumption W1 of the peak P1, and W8 <W7 <W1. It has become. The total power consumption of the three units is as shown in FIG. 7 (d), and the power consumption at the peak time is smaller than the conventional one. In the modification shown in FIG. 7, the start time may be changed for each of the turbo molecular pumps TMP1 to TMP7.
[0021]
As described above, in the first embodiment, the turbo molecular pump at the time of starting the apparatus is shifted by shifting the start time of the plurality of turbo molecular pumps TMP1 to TMP7 from each other or lengthening the starting operation time. The peak power regarding the whole of TMP1 to TMP7 can be reduced as compared with the prior art. As a result, the capacity of the power supply unit 23 (see FIG. 2) of the semiconductor manufacturing apparatus 1 can be reduced, and the power supply unit can be reduced in size and cost.
[0022]
-Second Embodiment-
In the second embodiment, a pump system on the premise that a plurality of turbo molecular pumps are used as an exhaust device of one device will be described. FIG. 8 is a diagram showing the configuration of the pump system. In addition, the same code | symbol was attached | subjected to the part similar to FIG. In the first embodiment described above, as shown in FIGS. 1 and 2, seven turbo molecular pumps each including a pump body 10 and a power supply device 11 are mounted on the semiconductor manufacturing apparatus 1. On the other hand, in the pump system shown in FIG. 8, seven pump bodies 10, seven drive devices 30 provided corresponding to each pump body 10, and a common supply of DC power to the seven drive devices 30. Power conversion unit 31. The drive device 30 corresponds to a portion obtained by removing the power change unit 16 from the power supply unit 11 in FIG. 2, and drives and controls the magnetic bearing 13 and the motor 21 by the power from the power conversion unit 31.
[0023]
AC power is supplied to the power conversion unit 31 via the power supply unit 23 of the semiconductor manufacturing apparatus. On the other hand, on / off of the magnetic bearing control circuit 15 and the drive control circuit 20 of each drive device 30 is controlled by the control unit 24. Each pump main body 10 is driven and controlled by the same method as described in the first embodiment. That is, the activation start times of the pump bodies 10 are shifted from each other or the activation operation time is lengthened so that the peak power when the seven units are combined is reduced.
[0024]
Therefore, similarly to the first embodiment, the capacity of the power supply unit 23 of the semiconductor manufacturing apparatus can be reduced as compared with the conventional case, and the size and cost can be reduced. Furthermore, in the second embodiment, since power is supplied from the common power conversion unit 31 to the seven pump bodies 10 and the drive device 30, compared to the case where the seven power conversion units 16 are provided. Downsizing and cost reduction. Furthermore, the peak power for the power conversion unit 31 can be made considerably smaller than seven times the peak power W1 of the power conversion unit 16 (FIG. 2), and the power conversion units 16 for seven units are simply combined into one. Can be reduced in size and cost.
[0025]
In the example shown in FIG. 8, the on / off of each driving device 30 is controlled by the control unit 24 on the device side. However, a pump control unit 32 is separately provided on the pump system side as shown in FIG. The on / off of each driving device 30 may be controlled by the unit 32. In this case, when receiving the device activation signal from the device-side control unit 24, the pump control unit 32 sequentially activates the pump main body 10 at preset time intervals. That is, the control unit 24 on the apparatus side may have a conventional configuration that does not need to consider the starting order of the turbo molecular pump at the time of starting the apparatus. Therefore, it becomes easy to replace the conventional seven independent turbo molecular pumps with the pump system shown in FIG.
[0026]
In the embodiments described above, the semiconductor manufacturing apparatus has been described as an example. However, the present invention can be applied to any apparatus that uses a plurality of turbo molecular pumps. Further, the number of turbo molecular pumps installed in the apparatus is not limited to seven.
[0027]
In the correspondence between the embodiment described above and the elements of the claims, the semiconductor manufacturing apparatus 1 is the apparatus of claim 1, the controller 24 is the controller, and the pump body 10 is the turbo molecular pump of claim 2. The pump control unit 32 constitutes a control unit.
[0028]
【The invention's effect】
As described above, according to the present invention, when a plurality of turbo molecular pumps are started, the generation time of the power consumption peak immediately before the rated rotation at the time of pump activation differs from pump to pump. The peak value of can be reduced. As a result, the power supply capacity of the device equipped with the turbo molecular pump can be kept low, and the cost of the device can be reduced.
[Brief description of the drawings]
FIG. 1 is a plan view showing an example of the configuration of a semiconductor manufacturing apparatus.
FIG. 2 is a diagram showing a schematic configuration of turbo molecular pumps TMP1 to TMP7.
FIG. 3 is a diagram showing an example of control of turbo molecular pumps TMP1 to TMP3, (a) to (c) showing the relationship between the operating state, the rotational speed and the power consumption, and (d) the total power consumption. Indicates.
FIG. 4 is a diagram showing the total power consumption in comparison with the conventional case.
FIG. 5 is a diagram showing a first modified example, and (a) to (c) show the relationship between the operating state of the turbo molecular pumps TMP1 to TMP3, the rotational speed, and the power consumption.
FIG. 6 is a diagram showing the total power consumption in the first modification compared with the conventional case.
FIG. 7 is a diagram showing a second modification, wherein (a) to (c) show the relationship between the operating state of the turbo molecular pumps TMP1 to TMP3 and the rotational speed and power consumption, and (d) shows the total Of power consumption.
FIG. 8 is a diagram showing a configuration of a pump system in a second embodiment.
9 is a view showing a modification of the pump system shown in FIG.
FIG. 10 is a diagram showing the relationship between the operating state of the turbo molecular pump, the rotation speed, and the power consumption.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Semiconductor manufacturing apparatus 2-5 Process chamber 6 Load chamber 7 Unload chamber 8 Transfer chamber 10 Pump main body 11 Power supply device 16,31 Power conversion part 22 Controller 23 Power supply part 24 Control part 30 Drive apparatus 32 Pump control part
TMP1 ~ TMP7 turbo molecular pump

Claims (4)

A plurality of power peaks occurrence time of startup of the turbo molecular pump is so different from each other in each turbo-molecular pump, the different length respectively the start operation time of each turbo-molecular pump with initiating start the turbo molecular pump simultaneously A device comprising a plurality of turbo molecular pumps, characterized in that a control device for controlling the temperature is provided. Multiple turbomolecular pumps,
A plurality of drive units that are provided for each of the plurality of turbo molecular pumps and that drive and control corresponding turbo molecular pumps;
A power converter that converts AC power into DC power and supplies the converted DC power to each of the plurality of drive devices;
Wherein the plurality of such power peak occurrence time of startup of the turbo molecular pump are different for each turbo-molecular pump, and a control unit for controlling the start operation time of each turbo-molecular pump in different lengths A pump system characterized by that. A device comprising a plurality of turbo molecular pumps having a pump body and a drive device in which the startup operation time of the pump body is set,
According to the number of turbo molecular pumps provided, a control device is provided to change the start-up operation time set for each drive device to be longer and to start the turbo molecular pumps simultaneously. A device comprising a plurality of turbo molecular pumps. Multiple turbomolecular pumps,
A plurality of driving devices that are provided for each of the plurality of turbo molecular pumps and that control driving of the corresponding turbo molecular pumps with a set start-up operation time;
A power converter that converts AC power to DC power and supplies the converted DC power to each of the plurality of drive devices;
A pump system comprising: a control unit configured to change the start-up operation time set in each driving device in accordance with the number of the turbo molecular pumps provided.

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