KR20200135154A - Vacuum opening/closing valve - Google Patents

Abstract

Provided is a vacuum opening and closing valve capable of suppressing vibration generated when a valve body is operated. The vacuum opening and closing valve (30) is disposed between a vacuum chamber (11) and a vacuum pump (15), and discharges air from the vacuum chamber (11) in accordance with the opening and closing of a poppet valve body (33A). The vacuum opening and closing valve (30) comprises: a vacuum pressure control device (70) performing an opening degree indication designating an opening degree of the poppet valve body (33A); and a servo valve (60) operating the valve body in a position corresponding to the opening degree designated by the opening degree indication. The opening degree indication for opening degree control, by which the servo valve (60) changes the position of the poppet valve body (33A) from a first position (opening degree X1) to a second position (opening degree X2) within a predetermined time, designates an opening degree corresponding to a third position (opening degree X3) between the first and second positions, and then gradually changes from the opening degree corresponding to the third position (opening degree X3) to an opening degree corresponding to the second position (opening degree X2).

Description

Vacuum opening/closing valve{VACUUM OPENING/CLOSING VALVE}

The present invention is a vacuum opening/closing valve that is disposed between a vacuum chamber and a vacuum pump to exhaust the vacuum chamber by opening/closing operation of the valve body, and the opening degree specifying the opening degree of the valve body The present invention relates to a vacuum opening/closing valve comprising a control device for giving an instruction, and a control valve for operating a valve element at a position corresponding to a designated opening degree based on an opening instruction.

In a semiconductor manufacturing apparatus, a vacuum opening/closing valve is provided between a vacuum chamber in which a wafer is disposed and a vacuum pump to control the pressure of the vacuum chamber. Recently, with the spread of ALD (Atomic Layer Deposition), the manufacturing cycle of semiconductors is increasing at high speed, and since pressure control of the vacuum chamber is performed at high speed, the vacuum opening/closing valve also opens and closes the valve body at high speed. do. At this time, it is conceivable to use a vacuum pressure control system as disclosed in Patent Document 1. As the vacuum switch valve used in the vacuum pressure control system, a servo valve with high responsiveness is used to control the opening degree of the valve element, and the valve element of the vacuum switch valve can be operated at high speed with high precision.

Japanese Patent No. 5086166

However, the prior art has the following problems.

When the vacuum switch valve opens and closes the valve body at high speed, the applicant has discovered by experiment that a sudden change in internal pressure occurs in the inside of the vacuum switch valve, resulting in vibration in the vacuum switch valve.

For example, in a conventional vacuum switch valve, when the opening degree of the valve body is X1 to X2 (e.g., when the closed valve is completely opened), the servo valve is , As shown in Fig. 11, an opening degree instruction C21 is received from the control device so that the opening degree of the valve body is X2 (time point t0). In accordance with this opening instruction C21, the servovalve controls the valve body, and the valve body starts driving toward X2 at the time point t1, as shown in the waveform PV21 in Fig. 11 or 12. And at the time point t2, it reaches X2. Since the movement of the valve body is very high, a sudden fluctuation occurs in the internal pressure of the vacuum switch valve at the time t1 when the valve body starts to move. The fluctuation of the internal pressure is indicated by the waveform P21 shown in Fig. 12, and it is clear that the fluctuation is rapidly changed at the time point t1 at which the valve body starts to move. Due to this sudden fluctuation of the internal pressure, vibration occurs in the vacuum switch valve.

When vibration occurs in the vacuum opening/closing valve, the vibration is transmitted to the vacuum chamber by propagating the pipe, and there is a problem that particles adhering to the inner wall surface of the vacuum chamber may peel off and fall. When the peeled off particles adhere to the wafer surface, it may lead to defects in the semiconductor, which adversely affects the yield of semiconductor manufacturing. Therefore, a vacuum switch valve capable of suppressing vibration as much as possible is required.

On the other hand, conventionally, even if vibration occurred in the vacuum switch valve, it was not a big problem. However, with the recent spread of ALD, miniaturization of semiconductor manufacturing apparatuses has progressed for the purpose of reducing waste of gas used. , The above problem has been made present. Because, due to the miniaturization of the semiconductor manufacturing apparatus, high density inside the semiconductor manufacturing apparatus is in progress, and the location of the vacuum switch valve is closer to the vacuum chamber than before, so that the vibration generated by the vacuum switch valve is easily transmitted to the vacuum chamber. Because I lost.

The present invention is to solve the above problems, and an object of the present invention is to provide a vacuum open/close valve capable of suppressing vibrations generated when a valve body is operated.

In order to solve the above problems, the vacuum switch valve of the present invention has the following configuration.

(1) A vacuum opening/closing valve that is disposed between the vacuum chamber and the vacuum pump to exhaust the vacuum chamber by the opening and closing operation of the valve element, a control device that issues an opening instruction designating the opening degree of the valve element, and an opening instruction In a vacuum opening/closing valve comprising a control valve for operating the valve body at a position corresponding to an opening degree designated according to the control valve, the control valve operates the position of the valve body from a first position to a second position within a predetermined time. The opening degree instruction for performing control is characterized in that after designating an opening degree corresponding to a third position between the first and second positions, the opening degree corresponding to the third position gradually changes from the opening degree corresponding to the second position. To do.

(2) In the vacuum switch valve described in (1), the third position is an approximately intermediate position between the first position and the second position, and the gradual change is performed in approximately half of the predetermined time. To do.

(3) In the vacuum opening/closing valve described in (1) or (2), the gradual change is characterized in that the gradual change gradually changes in proportion to the passage of time, from the opening degree corresponding to the third position to the opening degree corresponding to the second position. To do.

(4) In the vacuum switch valve according to any one of (1) to (3), the vacuum switch valve is used in a semiconductor manufacturing apparatus using an atomic layer deposition method, and is disposed adjacent to the vacuum chamber. .

The vacuum switch valve of the present invention has the following functions and effects by having the above configuration.

According to the vacuum switch valve described in (1), it is possible to suppress the vibration generated when the valve body is operated.

In the conventional vacuum switch valve, when the valve body is operated from the first position to the second position, the control device only designates an opening degree corresponding to the second position as an opening degree instruction for the control valve. Then, since the valve body is rapidly operated toward the second position, a rapid fluctuation occurs in the internal pressure of the vacuum switch valve, and vibration is generated in the vacuum switch valve.

On the other hand, in the present invention, when the valve body is operated from the first position to the second position, the control device provides an opening instruction for the control valve, first corresponding to a third position between the first position and the second position. Specify the opening degree. After that, the designated opening degree is gradually changed from the opening degree corresponding to the third position to the opening degree corresponding to the second position. By controlling in this way, the valve body is not rapidly operated toward the second position, but first starts the operation toward the third position, and then operates to the second position according to the gradually changing opening direction instruction. Accordingly, the valve body does not perform a sudden operation, and it is possible to prevent a sudden fluctuation of the internal pressure of the vacuum switch valve, and it is possible to suppress the vibration generated in the vacuum switch valve. If the vibration generated in the vacuum opening/closing valve can be suppressed, the vibration transmitted to the vacuum chamber is also suppressed, and the possibility of the particles adhering to the inner wall of the vacuum chamber being peeled off and adversely affecting the yield of semiconductor manufacturing is reduced.

According to the vacuum opening/closing valve described in (2), it is possible to suppress the vibration generated when the valve body is operated without affecting the cycle time in which the valve body is operated.

In the case of operating from the first position to the second position of the valve body, the control device first designates an opening degree corresponding to an approximately intermediate position between the first position and the second position as an opening direction instruction for the control valve. After that, the specified opening degree is gradually changed from the opening degree corresponding to the approximately intermediate position to the opening degree corresponding to the second position. By controlling in this way, the valve body is not rapidly operated toward the second position, but first starts the operation toward an approximately intermediate position, and then operates to the second position according to the gradually changing opening direction instruction. Therefore, the valve body does not perform abrupt operation, and it is possible to prevent sudden fluctuations in the internal pressure of the vacuum switch valve, and it is possible to suppress the vibration generated in the vacuum switch valve.

In addition, the gradual change of the opening direction instruction from the approximate intermediate position to the second position takes about half of the predetermined time for the valve body to operate from the first position to the second position, so that the valve body is moved from the first position to the second position. The applicant found by experiment that it is possible to suppress the vibration generated in the vacuum switch valve without affecting the time of operation to the position.

For example, when the time (cycle time) for operating the valve body from the first position to the second position is set to 1 second, in a conventional vacuum switch valve, the control device provides the control valve as an opening instruction. The opening degree corresponding to the 2 position was only specified, and the valve body was operated in 1 second.

On the other hand, in the present invention, the control device first designates an opening degree corresponding to the third position between the first position and the second position as an opening direction instruction for the control valve. After that, the designated opening degree is gradually changed over about 0.5 seconds from the opening degree corresponding to the third position to the opening degree corresponding to the second position. By performing the control in this way, the valve body can be operated from the first position to the second position in about 1 second, thereby preventing the occurrence of vibration in the vacuum switch valve and securing a cycle time equivalent to that of the conventional vacuum switch valve. I can.

According to the vacuum opening/closing valve described in (3), the opening degree specified in accordance with the opening direction instruction gradually changes in proportion to the passage of time from the opening degree corresponding to the third position to the opening degree corresponding to the second position. It operates smoothly, and more surely, it is possible to suppress the vibration generated when the valve body is operated.

According to the vacuum switch valve described in (4), the vacuum switch valve of the present invention can suppress vibration generated when the valve body is operated, and can prevent vibration from being transmitted to an adjacent vacuum chamber. Accordingly, the risk of peeling off particles attached to the inner wall surface of the vacuum chamber is reduced, and the possibility of adversely affecting the yield of semiconductor manufacturing, such as leading to defects in the semiconductor when the peeled particles adhere to the wafer surface, is reduced.

1 is an explanatory diagram showing the configuration of a vacuum pressure control system using a vacuum switch valve according to the present embodiment.
2 is a cross-sectional view showing a closed state of the vacuum switch valve according to the present embodiment.
3 is a side view of the vacuum switch valve according to the present embodiment.
4 is a cross-sectional view showing an open state of the vacuum switch valve according to the present embodiment.
Fig. 5 is an explanatory diagram showing the configuration of a servo valve used in the vacuum switch valve according to the present embodiment.
6 is a graph showing an opening instruction made by the vacuum pressure control device according to the present embodiment and a behavior of a poppet valve body.
7 is a graph showing a command signal given to the servo valve.
8 is a graph showing the behavior of the poppet valve body according to the present embodiment and variations in the internal pressure of the vacuum switch valve.
9 is a graph showing vibration in the X direction generated in the vacuum switch valve according to the present embodiment.
10 is a graph showing vibration in the Z direction generated in the vacuum switch valve according to the present embodiment.
Fig. 11 is a graph showing an opening instruction made from a conventional vacuum pressure control device and a behavior of a poppet valve body.
12 is a graph showing the behavior of a conventional poppet valve body and fluctuations in the internal pressure of the vacuum switch valve.
13 is a graph showing vibrations in the X direction generated in a conventional vacuum switch valve.
14 is a graph showing vibrations in the Z direction generated in a conventional vacuum switch valve.
Fig. 15 is an explanatory view showing a method of measuring vibration generated in the vacuum switch valve.
Fig. 16 is a graph showing an opening instruction made by the vacuum pressure control device according to the present embodiment and a behavior of a poppet valve body.
17 is a graph showing the behavior of the poppet valve body according to the present embodiment and variations in the internal pressure of the vacuum switch valve.
18 is a graph showing vibration in the X direction generated in the vacuum switch valve according to the present embodiment.
19 is a graph showing vibrations in the Z direction generated in the vacuum switch valve according to the present embodiment.
Fig. 20 is a graph showing an opening instruction made from a conventional vacuum pressure control device and a behavior of a poppet valve body.
Fig. 21 is a graph showing the behavior of a conventional poppet valve body and fluctuations in the internal pressure of the vacuum switch valve.
22 is a graph showing the vibration in the X direction generated in a conventional vacuum switch valve.
23 is a graph showing vibrations in the Z direction generated in a conventional vacuum switch valve.

An embodiment of the vacuum switch valve 30 of the present invention will be described in detail with reference to the drawings.

1 is an explanatory view illustrating the configuration of a vacuum pressure control system 1 using a vacuum open/close valve 30. In the case of surface treatment of the wafer 150 in a semiconductor manufacturing apparatus using ALD, the vacuum pressure control system 1 includes a process gas and a purge gas (for example, nitrogen) in the vacuum chamber 11 in which the wafer 150 is disposed. Gas N ₂ ) is alternately supplied and exhausted.

As shown in FIG. 1, the vacuum pressure control system 1 is a vacuum chamber 11, a vacuum pump 15, an air supply source 20, a vacuum opening/closing valve 30, and a servo valve 60. (See Figs. 3 and 5), and a vacuum pressure control device 70 that is electrically connected to the vacuum opening/closing valve 30 and the like. In this vacuum pressure control system 1, as a power source for opening and closing the vacuum switch valve 30, drive air AR (refer to FIG. 5) supplied from the air supply source 20 is used as a fluid.

In the gas supply port 11a of the vacuum chamber 11, a supply source of the process gas used for surface treatment on the wafer 150 disposed in the vacuum chamber 11 and the process gas in the vacuum chamber 11 are purged. A supply source of the nitrogen gas N ₂ to be used is connected in parallel.

On the other hand, to the gas exhaust port 11b of the vacuum chamber 11, a first port 39 of a vacuum opening/closing valve 30 to be described later is connected. The vacuum switch valve 30 is connected to the air supply source 20 by a pipe, and between the air supply source 20, a stop valve 21 (see Fig. 3) which is a fluid flow prevention valve, and The valve opening is also connected to the hand valve 14 (see Fig. 3), which is a regulating part. In addition, a chamber pressure sensor 12 is connected between the gas exhaust port 11b and the vacuum switch valve 30 via a shutoff valve 13, and the chamber pressure sensor 12 controls the vacuum pressure. It is electrically connected to the device 70. Furthermore, the second port 40 of the vacuum opening/closing valve 30 is connected to the vacuum pump 15.

Next, the vacuum switch valve 30 will be described with reference to FIGS. 2 to 4.

2 is a cross-sectional view showing a closed state of the vacuum opening/closing valve 30. 3 is a side view of FIG. 2. 4 is a cross-sectional view showing an open state of the vacuum switch valve 30.

The vacuum switch valve 30 is a pilot cylinder portion 32 positioned on the valve side (upper in FIGS. 2 and 4 in FIGS. 2 and 4) in the valve lift direction (upward and downward direction in FIGS. 2 and 4) of the poppet valve body 33A. ), and a bellows-type poppet valve 31 located on the closed side (in Fig. 2 and 4, below).

The pilot cylinder unit 32 includes a single-acting pneumatic cylinder 43 closed in the vertical direction in FIG. 2, and in the interior of the single-acting pneumatic cylinder 43, a single-acting pneumatic cylinder 43 is provided via a bellows ram 50. It includes a piston (41) accommodated so as to be movable in the direction of the valve lift. And the piston 41 is biased to the closed side by a return spring 42.

On the other hand, since the piston 41 is to drive the inside of the single-acting pneumatic cylinder 43 via the bellows ram 50, a stick slip of the piston 41 does not occur, and the piston 41 Silver, it is possible to drive the inside of the single-acting pneumatic cylinder 43 with high responsiveness and accurate positioning accuracy.

In addition, in the pilot cylinder part 32, when the piston 41 moves in the opening and closing direction, the displacement amount of the piston 41 as much as the displacement from the position of the bottom dead center of the piston 41, that is, the vacuum opening/closing valve 30 A displacement sensor 51 for non-contact measurement of the opening degree of is provided. This displacement sensor 51 is electrically connected to the vacuum pressure control device 70.

The bellopram 50 is a cylindrical diaphragm with a bottom in which a base fabric such as polyester, polyamide, or aramid is integrally molded with rubber. The central portion of the bellows ram 50 is fixed to the closed side end of the piston 41. In addition, this bellows ram 50 is clamped and fixed to the outer circumferential portion of the single-acting pneumatic cylinder 43 between the lower end of FIG. 2 and the upper end of the cylinder chamber wall 44 in FIG. 2, and the outer peripheral surface of the piston 41 Between the inner peripheral surfaces of the single-acting pneumatic cylinder 43, it is deeply folded upward in FIG. Accordingly, it has a stroke in the valve lift direction, and can follow along with the movement of the piston 41 on the open side. In this bellows ram 50, when the drive air AR is supplied between the piston 41 and the cylinder chamber wall 44 in the valve lift direction, that is, into the supply air storage chamber AS shown in FIG. In the frame 50, the effective water pressure area due to the drive air AR is kept constant.

In addition, an on-off valve pressure sensor 52 (see Fig. 3) for measuring the pressure of the supplied drive air AR is connected to the supply air storage chamber AS. The on-off valve pressure sensor 52 is electrically connected to the vacuum pressure control device 70.

A piston rod 37 is attached to the central portion of the piston 41 in the radial direction, and the piston rod 37 is extended inside the bellows poppet valve portion 31.

The bellows type poppet valve part 31 has a poppet valve body 33A therein, and the lower end of the piston rod 37 in Fig. 2 is connected to the poppet valve body 33A. As the piston 41 is driven in the valve lift direction, the piston rod 37 is also driven in the same direction, so that the poppet valve body 33A connected to the piston rod 37 is opened or closed. Further, a bellows 38 disposed so as to cover the outer side in the radial direction of the piston rod 37 is attached to the poppet valve body 33A at one end thereof in the axial direction, and the valve lift direction of the poppet valve body 33A It is designed to expand and contract with the drive of the motor.

The poppet valve body 33A and the O-ring retaining member 33B are fixed at the closed side of the poppet valve body 33A, and an O-ring mounting portion between the poppet valve body 33A and the O-ring retaining member 33B ( 34) is provided. The O-ring 35 is attached to the O-ring mounting portion 34, and the inner wall of the O-ring mounting portion 34 is in a reverse taper shape, so that the O-ring 35 does not come out.

The poppet valve body 33A is pressed by a return spring 42 to the closed side in the valve lift direction via the piston 41. For this reason, when the drive air AR is not supplied from the air supply source 20 to the supply air receiving chamber AS through the servo valve 60, the O-ring 35 is connected to the poppet valve body 33A and It is pressurized by the valve seat 36. Accordingly, the first port 39 is blocked by the poppet valve body 33A, and the vacuum opening/closing valve 30 is closed.

On the other hand, when the driving air AR is supplied to the supply air receiving chamber AS, the pressure in the supply air receiving chamber AS increases. And, when the pressure exceeds the biasing force of the return spring 42, the piston 41 resists the biasing force of the return spring 42 and moves to the opening side in the valve lift direction, and accordingly, the poppet valve body ( 33A) moves to the open side in the valve lift direction. When the poppet valve body 33A moves to the valve side, the O-ring 35 and the valve seat 36 are separated, the first port 39 and the second port 40 communicate with each other, and the vacuum open/close valve 30 Changes. Accordingly, the process gas or nitrogen gas N ₂ in the vacuum chamber 11 can be sucked by the vacuum pump 15.

A hand valve 14 is connected between the supply air storage chamber AS of the vacuum switch valve 30 and the air supply source 20. This hand valve 14, separate from the servo valve 60, is intake of the drive air AR to the supply air storage chamber A, and exhaust of the drive air AR from the supply air storage chamber AS. Is a valve that is performed by manual operation.

In the case of carrying out maintenance of the vacuum pressure control system 1, etc., by operating the hand valve 14 to intake and exhaust the drive air AR in the supply air storage chamber AS, the servo valve Without using (60), it is possible to simply open and close the vacuum switch valve (30). Accordingly, the workability of maintenance is improved compared to the case where the vacuum opening/closing valve 30 is opened and closed via the servo valve 60.

As described above, the vacuum pressure control system 1 is provided with a stop valve 21 (see Fig. 3). The input side of the stop valve 21 is connected to the air supply source 20, the exhaust flow path, and the supply air storage chamber AS of the vacuum opening/closing valve 30, and the output side is the first and second servo valves 60. It is connected to 3 ports (61, 63). This stop valve 21 prevents the drive air from flowing from the output side toward the port connected to the first port 61 of the servo valve 60 through the port connected to the air supply source 20 on the input side. It is a switchable 5-port valve. This stop valve 21 is electrically connected to the vacuum pressure control device 70.

By providing this stop valve 21, when there is no need to supply the drive air AR to the servo valve 60, such as when the vacuum pressure control system 1 is not operated, the drive air AR is an air supply source. Even if it is in a state flowing from 20 to the servo valve 60, the drive air AR is cut off by the stop valve 21 and is not supplied to the servo valve 60. Accordingly, it is possible to prevent useless consumption of the drive air AR in the servo valve 60.

Next, the servo valve 60 will be described with reference to FIG. 5.

5 is an explanatory diagram for explaining the configuration of the servo valve 60.

The servo valve 60 includes a first port 61 connected to the air supply source 20 via a stop valve 21, and a second port connected to the supply air storage chamber AS of the vacuum switch valve 30. 62, and a third port 63 for exhausting the supply air storage chamber AS to the exhaust side flow path through the stop valve 21. The second port 62 is located between the first port 61 and the third port 63 in the stroke direction of the servo valve 60 (in FIG. 5, left and right directions). In addition, the servo valve 60 is installed on the outer periphery of the servo valve cylinder 65, the coil bobbin 69, and the coil bobbin 69, and the first coils ( 66A) and a second coil 66B, a spool 64 connected to the magnet 67 at one end side in the stroke direction (left in FIG. 5), and a control unit 68. The control unit 68 of this servo valve 60 is electrically connected to the vacuum pressure control device 70.

When the servo valve 60 is energized to the first coil 66A, the electromagnetic force generated in the first coil 66A and the magnetic force generated by the magnet 67 cause the spool 64 to become the servo valve cylinder 65. The inside is driven toward one end side in the stroke direction (left in Fig. 5), and stops accurately at a position corresponding to the command voltage value. On the other hand, when the second coil 66B is energized, the electromagnetic force generated in the second coil 66B and the magnetic force generated by the magnet 67 cause the spool 64 to travel inside the servo valve cylinder 65 in the stroke direction. It drives toward the short side (in Fig. 5, right), and stops precisely at the position corresponding to the command voltage value.

Therefore, when the command voltage corresponding to the command signal to the first coil 66A and the second coil 66B is input to the control unit 68 of the servo valve 60 by the vacuum pressure control device 70, the spool 64 ) Is driven quickly with high responsiveness based on the value of this command voltage. Then, the spool 64 moves in the stroke direction to a predetermined position corresponding to the value of this command voltage, while sliding in the servo valve cylinder 65, and stops at the correct position.

5, the spool 64 blocks the first port 61 and the third port 63, so that supply air to the supply air storage chamber AS and exhaust from the supply air storage chamber AS are not performed. The spool 64 is in a stroke direction (left and right direction in Fig. 5), that is, a direction connecting the first port 61 and the third port 63 with the second port 62 interposed therebetween. As a result, the first port 61 or the third port 63 is opened or closed by sliding the servo valve cylinder 65.

The opening degree of the vacuum switch valve 30 is controlled by the servo valve 60.

Specifically, when the spool 64 stops at a position on the one end side (left in FIG. 5) in the stroke direction in the servo valve cylinder 65, the connection flow path between the first port 61 and the second port 62 is It becomes blocked. On the other hand, the third port 63 is fully opened, and a connection passage between the third port 63 and the second port 62 is opened. Accordingly, it is possible to rapidly exhaust the drive air AR from the supply air storage chamber AS through the third port 63 from the second port 62. When the driving air AR is exhausted from the supply air receiving chamber AS, the piston 41 operates in the closed valve direction by the force of the return spring 42, and the poppet valve body 33A is closed. Since it operates in the direction, the vacuum opening and closing valve 30 is closed.

In addition, when the spool 64 stops at the position of the other end of the servo valve cylinder 65 in the stroke direction (in Fig. 5, right), the connection flow path between the third port 63 and the second port 62 is blocked. State. On the other hand, the first port 61 is deployed, and a connection passage between the first port 61 and the second port 62 is developed. Accordingly, it is possible to rapidly supply the drive air AR from the first port 61 to the supply air receiving chamber AS of the vacuum switch valve 30 through the second port 62. When air is supplied to the supply air receiving chamber (AS), the pressure in the supply air receiving chamber (AS) rises, and when the pressure exceeds the negative force of the return spring 42, the piston 41 operates as a change report. do. As a result, the poppet valve body 33A operates in the opening direction, so that the vacuum opening/closing valve 30 is opened.

Furthermore, the spool 64 not only expands the first port 61 or the third port 63, but also closes a part of the first port 61 or the third port 63 with high precision. Accordingly, the flow rate of the drive air AR flowing from the first port 61 toward the second port 62 and the drive air AR flowing from the second port 62 toward the third port 63 The flow rate can be adjusted quickly and precisely with high responsiveness.

Therefore, in the servo valve 60, the driving air AR flowing into the first port 61 is rapidly transferred to the supply air receiving chamber AS of the vacuum opening/closing valve 30 through the second port 62. Can be supplied. Further, the drive air AR flowing from the supply air storage chamber AS to the second port 62 can be rapidly exhausted through the third port 63. Further, the flow rate of the drive air AR flowing through the first port 61 and the flow rate of the drive air AR flowing through the third port 63 can be simultaneously adjusted with high precision. By adjusting the flow rate of the drive air AR, the pressure in the supply air accommodating chamber AS is adjusted, and the opening degree of the vacuum opening/closing valve 30 is controlled.

Here, a method of controlling the servo valve 60 by the vacuum pressure control device 70 will be described.

In the vacuum pressure control system 1, the vacuum pressure measurement value in the vacuum chamber 11 measured by the chamber pressure sensor 12 is fed back to the vacuum pressure control device 70, and this vacuum pressure measurement value and the target The opening direction instruction obtained by comparing and calculating the vacuum pressure value is output. The opening direction instruction designates the opening degree of the poppet valve body 33A.

Further, the displacement detection signal (measured value of the opening degree) measured by the displacement sensor 51 of the opening degree of the vacuum opening/closing valve 30 is fed back to the vacuum pressure control device 70, and compared with the opening instruction, A command signal to the servo valve 60 is calculated. The command signal is a voltage value, and is applied to the control unit 68 of the servo valve 60 to move the spool 64 of the servo valve 60 to a position corresponding to the voltage value.

Conventionally, the opening direction instruction for moving the poppet valve body 33A from X1 to X2 in the opening direction was only outputting the opening direction instruction C21 of the opening degree X2, as shown in FIG. 11. Here, for example, when the opening degree X1 is the closed state and the opening degree X2 is the maximum open state, when the poppet valve body 33A is operated from the closed state to the maximum open state, the opening direction instruction C21 corresponding to the maximum open state is performed. It was only. Along with this, the command signal S21 applied to the control unit 68 is rapidly applied at the time point t0 at which the opening instruction C21 is output, as shown in Fig. 7.

The behavior of the poppet valve body 33A is indicated by waveform PV21 in Figs. 11 and 12.

After the opening direction instruction C21 is output at the time point t0, the operation starts from the time point t1, and the opening degree X2 is reached at the time point t2. At the time point t1, it can be seen that the poppet valve body 33A is rapidly starting to move from the point where the waveform PV21 rises sharply at an angle close to the right angle.

Since the poppet valve body 33A starts to move rapidly, a rapid fluctuation occurs in the internal pressure of the vacuum switch valve 30. The fluctuation of the internal pressure is represented by waveform P21 shown in FIG. 12. From the time point t1 when the poppet valve body 33A starts its operation, the internal pressure gradually increases from Y1 to Y2, but it is clear that a sudden fluctuation occurs in the waveform P21 at the time point t1.

And, due to the sudden fluctuation of the internal pressure, vibration occurs in the vacuum opening/closing valve 30.

In addition, this vibration is measured by the test method as shown in FIG. Specifically, in a state in which the test pipe 71 having a length of 600 mm is connected to the first port 39 of the vacuum switch valve 30, it is placed horizontally on the test jigs 72A, 72B, and the vacuum switch valve ( 30). The accelerometer 73 is attached to the end of the test pipe 71 on the opposite side to the end connected to the first port 39. The accelerometer 73 can measure vibrations in the X direction (in Fig. 15, left and right directions) and the Z direction (in Fig. 15, in the vertical direction) generated when the vacuum switch valve 30 is operated.

The vibration in the X direction is indicated by the vibration waveform VX21 shown in Fig. 13, and the vibration in the Z direction is indicated by the vibration waveform VZ21 shown in Fig. 14. Looking at these vibration waveforms VX21 and VZ21, it can be seen that vibration is largely generated at the time t1 when the poppet valve body 33A starts its operation.

When vibration occurs in the vacuum opening/closing valve, the vibration is transmitted to the vacuum chamber 11 through a pipe or the like, and there is a problem that particles attached to the inner wall surface of the vacuum chamber 11 may peel off and fall off. When the peeled off particles adhere to the surface of the wafer 150, it may lead to defects in the semiconductor and adversely affect the yield of semiconductor manufacturing. Therefore, a vacuum switch valve capable of suppressing vibration as much as possible is required.

In particular, with the recent miniaturization of semiconductor manufacturing apparatuses, the above problems have become present. Because, with the miniaturization of the semiconductor manufacturing apparatus, high density inside the semiconductor manufacturing apparatus is in progress, and the location of the vacuum opening/closing valve 30 is closer to the vacuum chamber 11 than before, and thus the vacuum opening/closing valve 30 occurs. This is because the vibration to be carried out is easily transmitted to the vacuum chamber 11.

On the other hand, in the vacuum opening/closing valve 30 according to the present embodiment, the opening instruction C21 of the opening degree X2 as shown in FIG. 11 for moving the poppet valve body 33A from X1 to X2 is Instead of being outputted, as shown in Fig. 6, first, the opening degree X3, which is approximately intermediate between the opening degree X1 and the opening degree X2, is output as the opening degree instruction C11. Thereafter, the opening degree designated by the opening degree instruction C11 gradually increases in proportion from the opening degree X3 to the opening degree X2 over time, and reaches X2 at the time point t3. Here, the time from the time point t0 to the time point t3 is about half of the time from the time point t0 to the time point t2. By outputting such an opening direction command C11, the command signal S11 applied to the control unit 68 is applied so that the voltage value gradually increases as shown in FIG. 7.

The behavior of the poppet valve body 33A is represented by waveform PV11 in Figs. 6 and 8. After the opening direction instruction C11 is output at the time point t0, the operation starts from the time point t1, and the opening degree X2 is reached at the time point t2. The time from the time point t0 to the time point t2 is the same as the conventional one.

The waveform PV11 is soaring at a shallow angle from the time point t1 compared to the conventional waveform PV21, and it is understood that the poppet valve body 33A is prevented from starting to move rapidly.

By preventing the sudden movement of the poppet valve body 33A, a sudden change in the internal pressure that has conventionally occurred in the vacuum switch valve 30 is prevented. The fluctuation of the internal pressure is represented by waveform P11 shown in FIG. 8. Waveform P11 gradually increases from the time point t1 at which the poppet valve body 33A starts operation, from Y1 to Y2, but at time t1, it rises gently compared to the waveform P21, and no sudden fluctuation occurs. It is clear that you are not.

The rapid fluctuation of the internal pressure indicated by the waveform P11 is suppressed, thereby preventing the occurrence of vibration in the vacuum switch valve 30.

The vibration in the X direction is represented by the vibration waveform VX11 shown in Fig. 9, and it can be seen that almost no vibration occurs at the time t1 when the poppet valve body 33A starts its operation. In addition, the vibration in the Z direction is represented by the vibration waveform VZ11 shown in FIG. 10, and at the time t1 when the poppet valve body 33A starts operation, a little vibration occurs, but compared to the conventional vibration waveform VZ11. It can be seen that there is a great improvement.

Incidentally, in the above description, the opening direction from the opening degree X1 to the opening degree X2, that is, the opening direction of the poppet valve body 33A is described, but it may be applied to the closing direction from the opening degree X2 to the opening degree X1.

Conventionally, the opening direction instruction for moving the poppet valve body 33A from the opening degree X2 to the opening degree X1 in the closing direction was only outputting the opening direction instruction C22 of the opening degree X1, as shown in FIG. For example, here, if the opening degree X2 is the maximum open state and the opening degree X1 is the closed state, when the poppet valve body 33A is operated to change the closed state from the maximum open state, the opening direction instruction C22 corresponding to the closed state is It was only done.

The behavior of the poppet valve body 33A is indicated by waveform PV22 in Figs. 20 and 21. After the opening direction instruction C22 is output at the time point t0, the operation starts from the time point t1, and the opening degree X1 is reached at the time point t2. Along with this, the internal pressure of the vacuum switch valve 30 gradually decreases from Y3 at the time point t1 at which the poppet valve body 33A starts operation to Y4 at the time point t2, as shown in waveform P22. .

At time t1, since the poppet valve body 33A starts to move rapidly toward the opening degree X1, in the vacuum opening/closing valve 30, as in the vibration waveforms VX22 and VZ22 shown in Figs. 22 and 23, the vibration in the X direction , Vibration in the Z direction is occurring. And, when the poppet valve body 33A is suddenly closed, the O-ring 35 collides with the valve seat 36, so even at the time t2 when the poppet valve body 33A reaches the opening degree X2, vibration in the X direction, Vibration in the Z direction is occurring. On the other hand, the vibration generated in the vacuum switch valve 30 is measured by the test method shown in FIG. 15.

On the other hand, in the vacuum opening/closing valve 30 according to the present embodiment, the opening instruction C22 of the opening degree X1 is output as in the prior art for moving the poppet valve body 33A from the opening degree X2 to the opening degree X1. Instead, as shown in Fig. 16, first, the opening degree X3, which is approximately intermediate between the opening degree X2 and the opening degree X1, is output as the opening degree instruction C12. After that, the opening degree designated by the opening degree instruction C12 gradually decreases in proportion from the opening degree X3 to the opening degree X1 as time passes, and reaches X1 at the time point t3. Here, the time from the time point t0 to the time point t3 is about half of the time from the time point t0 to the time point t2.

The behavior of the poppet valve body 33A when such an opening instruction C12 is made is indicated by waveform PV12 in FIGS. 16 and 17. The poppet valve body 33A starts the operation from the time point t1 after outputting the opening degree instruction C12 at the time point t0, and reaches the opening degree X1 at the time point t4. Along with this, the internal pressure of the vacuum switch valve 30 gradually decreases from Y3 at the time point t1 when the poppet valve body 33A starts operation to Y4 at the time point t4, as shown in waveform P12. .

First, by indicating the opening degree X3, the poppet valve body 33A is prevented from starting to move rapidly, and it can be seen that the vibration is suppressed at the time point t1, as in the vibration waveforms VX12 and VZ12 shown in Figs. 18 and 19. have. Further, it is understood that the impact when the O-ring 35 contacts the valve seat 36 when the poppet valve body 33A reaches the opening degree X1 is alleviated, and the vibration at the time point t4 is also suppressed. I can.

Accordingly, it can be seen that even if the above configuration is applied to the closing direction, it is possible to reduce the vibration generated in the vacuum opening/closing valve 30. However, the time from the time point t0 to the time point t4 is slightly longer than the time from the time point t0 to the time point t2 in the prior art, and the operation of the poppet valve body 33A tends to be delayed compared to the prior art. Therefore, it is most preferable to implement the present invention in the opening direction in which the operation of the poppet valve body 33A is not delayed.

(1) As described above, according to the vacuum opening/closing valve 30 of this embodiment, it is disposed between the vacuum chamber 11 and the vacuum pump 15, and the valve body (poppet valve body 33A) A control device (vacuum pressure control device 70), which is a vacuum switch valve 30 for evacuating the vacuum chamber 11 by an opening/closing operation, and giving an opening instruction designating the opening degree of the valve body (poppet valve body 33A) ), and a control valve (servo valve 60) for operating the valve body at a position corresponding to the designated opening degree according to the opening instruction, the control valve (servo valve 60) is , The opening direction instruction for performing the opening degree control to operate the position of the valve body (poppet valve body 33A) from the first position (opening degree X1) to the second position (opening degree X2) within a predetermined time, the first After designating the opening degree corresponding to the third position (opening degree X3) between the position and the second position, it gradually changes from the opening degree corresponding to the third position (opening degree X3) to the opening degree corresponding to the second position (opening degree X2). . Therefore, it is possible to suppress the vibration generated when the valve body (poppet valve body 33A) operates.

In the conventional vacuum switch valve, when operating the valve body (poppet valve body 33A) from a first position (open view X1) to a second position (open view X2), the control device (vacuum pressure control device 70) is , For the control valve (servo valve 60), only the opening degree corresponding to the second position (opening degree X2) was designated as the opening instruction. Then, since the valve body (poppet valve body 33A) is rapidly operated toward the second position (opening degree X2), a rapid fluctuation in the internal pressure of the vacuum open/close valve occurred, and vibration was generated in the vacuum open/close valve.

On the other hand, in the present invention, when operating the valve body (poppet valve body 33A) from the first position (open view X1) to the second position (open view X2), the control device (vacuum pressure control device 70), For the control valve (servo valve 60), as an opening direction instruction, first, an opening degree corresponding to a third position (opening degree X3) between the first position (opening degree X1) and the second position (opening degree X2) is designated. After that, the designated opening degree is gradually changed from the opening degree corresponding to the third position (opening degree X3) to the opening degree corresponding to the second position (opening degree X2). By controlling in this way, the valve body is not rapidly operated toward the second position (opening degree X2), but first, the operation is started toward the third position (opening degree X3), and then the second position according to the gradually changing opening direction instruction. It works up to (opening degree X2). Accordingly, the valve body does not perform a sudden operation, it is possible to prevent a sudden fluctuation of the internal pressure of the vacuum switch valve 30, it is possible to suppress the vibration generated in the vacuum switch valve 30. If the vibration generated in the vacuum opening/closing valve 30 can be suppressed, the vibration transmitted to the vacuum chamber 11 is also suppressed, and the particles adhering to the inner wall of the vacuum chamber 11 are peeled off and adversely affect the yield of semiconductor manufacturing. The possibility is reduced.

(2) In the vacuum opening/closing valve 30 described in (1), the third position (opening degree X3) is an approximately intermediate position between the first position (opening degree X1) and the second position (opening degree X2), gradually changing Silver is carried out in about half of the predetermined time. Therefore, it is possible to suppress the vibration generated when the valve body (poppet valve body 33A) operates without affecting the cycle time at which the valve body (poppet valve body 33A) operates.

When operating the valve body (poppet valve body 33A) from the first position (opening degree X1) to the second position (opening degree X2), the control device (vacuum pressure control device 70) is a control valve (servo valve ( 60)), as an opening direction instruction, first, an opening degree corresponding to an approximately intermediate position between the first position (opening degree X1) and the second position (opening degree X2) is designated. After that, the specified opening degree is gradually changed from the opening degree corresponding to the approximately intermediate position to the opening degree corresponding to the second position (opening degree X2). By controlling in this way, the valve body (poppet valve body 33A) is not rapidly operated toward the second position (opening degree X2), but first, the operation starts toward an approximately intermediate position, and then gradually changes in the opening direction instruction. Accordingly, it operates up to the second position (opening degree X2). Accordingly, the valve body does not perform a sudden operation, it is possible to prevent a sudden fluctuation of the internal pressure of the vacuum switch valve 30, it is possible to suppress the vibration generated in the vacuum switch valve 30.

In addition, the gradual change of the opening direction instruction from the intermediate position to the second position (opening degree X2) is approximately half of the predetermined time when the valve body operates from the first position (opening degree X1) to the second position (opening degree X2). By indenting, the valve body (poppet valve body 33A) does not affect the time during which the valve body (poppet valve body 33A) operates from the first position (open degree X1) to the second position (open degree X2), and occurs in the vacuum open/close valve 30 Applicants discovered by experimentation that vibration can be suppressed.

For example, when the time (cycle time) for operating the valve body from the first position (opening degree X1) to the second position (opening degree X2) is 1 second, in a conventional vacuum switch valve, the control device (vacuum pressure The control device 70 simply designates the opening degree corresponding to the second position (opening degree X2) as an opening instruction for the control valve (servo valve 60), and the valve body (poppet valve body 33A) Was operating in 1 second.

On the other hand, in the present invention, the control device (vacuum pressure control device 70) is a first position (opening degree X1) and a second position (opening degree) as an opening instruction for the control valve (servo valve 60). The opening degree corresponding to the third position (opening degree X3) between X2) is designated. After that, the designated opening degree is gradually changed over about 0.5 seconds from the opening degree corresponding to the third position (opening degree X3) to the opening degree corresponding to the second position (opening degree X2). By performing the control in this way, the valve body (poppet valve body 33A) can be operated from the first position (opening degree X1) to the second position (opening degree X2) in about 1 second, so that the vacuum opening/closing valve 30 vibrates. While preventing this from occurring, it is possible to ensure a cycle time equivalent to that of a conventional vacuum switch valve.

(3) In the vacuum opening/closing valve 30 described in (1) or (2), the gradual change is from the opening degree corresponding to the third position (opening degree X3) to the opening degree corresponding to the second position (opening degree X2). , It changes gradually in proportion to the passage of time. Therefore, the opening degree specified in accordance with the opening degree instruction gradually changes in proportion to the passage of time from the opening degree corresponding to the third position (opening degree X3) to the opening degree corresponding to the second position (opening degree X2), so that the valve body (poppet The valve body 33A operates smoothly, and more reliably, it is possible to suppress the vibration generated when the valve body (poppet valve body 33A) operates.

(4) In the vacuum switch valve 30 according to any one of (1) to (3), the vacuum switch valve 30 is used in a semiconductor manufacturing apparatus used in the atomic layer deposition method, and the vacuum chamber 11 It is placed close to and. Accordingly, the vacuum opening/closing valve 30 of the present invention can suppress the vibration generated when the valve body (poppet valve body 33A) operates, and prevents the vibration from being transmitted to the adjacent vacuum chamber 11. Can be prevented. Accordingly, the possibility of the particles adhering to the inner wall of the vacuum chamber 11 being peeled off is reduced, and when the peeled off particles adhere to the surface of the wafer 150, it leads to defects in the semiconductor, thereby adversely affecting the yield of semiconductor manufacturing. The fear of giving is reduced.

On the other hand, this embodiment is only a mere illustration and does not limit the present invention at all. Therefore, the present invention can, of course, be variously improved and modified within a range not departing from the gist.

For example, in the present embodiment, the spool 64 of the servo valve 60 is supposed to control the flow rate of the drive air AR by sliding in the longitudinal direction, but centering the central axis in the longitudinal direction. By performing one rotation, the flow rate of the drive air AR may be controlled.

11 Vacuum chamber
15 Vacuum pump
33A poppet valve body
60 Servo valve (an example of a control valve)
70 Vacuum pressure control device (an example of a control device)

Claims (5)

A vacuum opening/closing valve disposed between the vacuum chamber and the vacuum pump to evacuate the vacuum chamber by an opening/closing operation of the valve body, and a control device that issues an opening instruction designating an opening degree of the valve element; and the opening instruction In the vacuum opening and closing valve having a control valve for operating the valve body at a position corresponding to the opening degree designated according to,
The control valve, the opening direction control for operating the position of the valve body from the first position to the second position within a predetermined time, a third between the first position and the second position After designating the opening degree corresponding to the position, it characterized in that it gradually changes from the opening degree corresponding to the third position to the opening degree corresponding to the second position,
Vacuum switch valve.
The method of claim 1,
The third position is an approximately intermediate position between the first position and the second position,
The gradual change is characterized in that it takes about half the time of the predetermined time,
Vacuum switch valve.
The method of claim 1,
The gradual change is characterized in that it gradually changes in proportion to the passage of time, from the opening degree corresponding to the third position to the opening degree corresponding to the second position,
Vacuum switch valve.
The method of claim 2,
The gradual change is characterized in that it gradually changes in proportion to the passage of time, from the opening degree corresponding to the third position to the opening degree corresponding to the second position,
Vacuum switch valve.
The method according to any one of claims 1 to 4,
The vacuum switch valve is used in a semiconductor manufacturing apparatus using an atomic layer deposition method, and is disposed in close proximity to the vacuum chamber,
Vacuum switch valve.

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