JP4654370B1 - Vacuum gate valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the service life by preventing a decrease in life due to a collision or a long-term deterioration while improving processing efficiency in a chamber by enabling opening and closing at an ultra-high speed.
A vacuum gate valve 10 includes a casing 12 having an opening, a valve plate 14 that swings in the casing 12 to open and close the opening, and a motor 16 that drives the valve plate 14. The power of the shaft 16A is transmitted directly to the valve plate 14 via a flange 20 that rotates coaxially with the rotating shaft 16A and a rotating body 22 that is coupled to the flange 20 and the valve plate 14 on the same axis without using a gear. The rotating body 22 has a main body portion 22A and a shaft portion 22B extending from the main body portion 22A. The main body portion 22A is disposed above and below the main body portion 22A in the vertical direction via the roller bearing 28. By being held via the two thrust bearings 30A and 30B, the cover 26 is rotatably installed.
[Selection] Figure 1

Description

  The present invention relates to an improvement of a vacuum gate valve that is used, for example, in a processing chamber of a semiconductor device to evacuate various processing chambers. In particular, the valve plate is opened and closed at high speed to increase the processing speed, and for many years. It relates to reducing the deterioration and improving the service life.

  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. As this vacuum gate valve, in recent years, since it is advantageous in terms of space and can be manufactured relatively easily, a laterally swiveled gate valve that swings the valve plate in the casing in the lateral direction has been widely adopted. Yes.

  In this horizontal turning type vacuum gate valve, an expansion / contraction actuator is often used as a driving source for the oscillation (see, for example, Patent Documents 1 and 2). However, the expansion / contraction actuator has a limit in the speed at which the valve plate can be opened and closed, so that the processing efficiency in the chamber cannot be sufficiently improved, and the mass production demand cannot always be fully met. It was. In addition, when an actuator is used, there is a problem that the size of the vacuum gate valve is increased.

  For this reason, it is also conceivable to use a motor instead of an actuator as a drive source to transmit the drive force to the valve plate. In this case, in recent years when the valve plate has become larger and heavier, it can be said that it is common to connect the rotating shaft of the motor to the valve plate via a gear in order to ensure sufficient driving force. However, as the number of elements for power transmission increases, the processing speed also decreases. Problem arises.

  Furthermore, even when the valve plate swings at a high speed, especially in recent valve plates that have become larger and heavier, the motor is driven to generate vibrations as the valve plate swings. 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. Moreover, when the valve plate that opens and closes at high speed comes into contact with the casing or the like due to this vibration, the valve plate may be damaged. Therefore, especially when the gate valve is opened and closed at high speed, it is necessary to pay maximum attention to the influence of vibration.

  In addition, the valve plate is placed at the boundary of a space where the pressure difference between the atmospheric pressure and the vacuum is intense and is loaded, so it tends to be displaced especially during the initial movement for opening from the time when the processing chamber is sealed. There is a risk that the valve plate may be greatly warped and deformed or broken due to damage due to contact with the casing or the like, or because it receives pressure over a large area.

JP 2008-2834 A JP 2003-42310 A

  In view of the above problems, the problem to be solved by the present invention is that it can be opened and closed at an ultra-high speed to increase the processing efficiency in the chamber, while preventing a decrease in the life due to collisions and long-term deterioration and extending the service life. An object of the present invention is to provide a vacuum gate valve that can be improved.

  As a first means for solving the above-described problems, the present invention provides a vacuum including a casing having an opening, a valve plate that swings in the casing to open and close the opening, and a motor that drives the valve plate. The vacuum gate valve further includes power transmission means for directly transmitting the power of the rotation shaft of the motor to the valve plate on the same axis without using a gear, and the power transmission means is connected to the rotation shaft of the motor. And a rotating body connected to the flange and the valve plate and rotating together with the flange. The rotating body 22 extends from the main body part and is connected to the valve plate. Installed in a cover fixed to the casing, covered in the horizontal and vertical directions by the cover, and rotated The body part of the can be freely rotated in the cover by being held via two roller bearings arranged above and below the body part in the vertical direction via roller bearings in the lateral direction. The present invention provides a vacuum gate valve characterized by being installed in.

  According to the present invention, as a second means for solving the above-described problem, in the first solving means, the power transmission means is a rotating body in a direction in which a valve plate connected to the rotating body is separated from the opening of the casing. The spring further includes a spring for urging the valve, and the spring absorbs the displacement in the vertical direction of the valve plate.

  According to the present invention, as a third means for solving the above-described problem, in any one of the first and second solving means, the power transmission means is configured such that the valve plate is moved between the casing and the casing by the biasing force of the spring. The present invention provides a vacuum gate valve characterized in that the vacuum gate valve is rocked while holding the gap.

  According to the present invention, as a fourth means for solving the above-described problem, in any one of the second and third solving means, the spring is composed of a ring-shaped disc spring, and the entire lateral direction of the valve plate. The present invention provides a vacuum gate valve characterized by correcting an inclination in a direction.

  According to the present invention, as a fifth means for solving the above-described problems, in any one of the first to fourth solving means, the valve plate may have a portion positioned at the opening when the valve plate is in the closed position. The present invention provides a vacuum gate valve characterized in that the vacuum gate valve is formed thinner than this part.

  According to the present invention, as a sixth means for solving the above problems, in any one of the first to fifth solving means, the motor and the power transmission means are detachably connected to the valve plate. A vacuum gate valve characterized by the above is provided.

  According to the present invention, as described above, since the power transmission means for directly transmitting the power of the rotating shaft of the motor to the valve plate on the same axis without using a gear is provided, the driving force of the motor is directly transmitted to the valve plate. The valve plate can be opened and closed at an ultra-high speed of about 0.3 seconds, while the number of parts is reduced and deterioration caused by a collision during meshing can be suppressed. There is an actual benefit that can dramatically improve the number of years. Further, since the rotation is on the same axis, there is an actual advantage that vibration generated during the rotation can be reduced. Further, the power transmission means can be made compact compared with the case where a gear is used, and the size can be reduced. In addition to the real benefits of space saving, the rotating body is held in a freely rotating manner by a bearing with a small friction coefficient, so unlike a case where gears are used, there is little deterioration over time and sufficient driving force is achieved. While ensuring the service life, it is possible to improve the useful life and to rotate the rotating body without centering.

  According to the present invention, as described above, the rotational force of the rotating shaft of the motor is transmitted to the valve plate by the flange, and the valve plate is displaced in the vertical direction by the spring that biases the rotating body connected to the valve plate. Therefore, even if the pressure difference between the front and back of the valve plate is large, the displacement and warpage are canceled and the valve plate is adjusted to the specified position and shape. The breakage of the valve plate can be suppressed and the valve plate can be swung appropriately.

  According to the present invention, as described above, the valve plate is swung while holding the gap between the casing and the casing by the biasing force of the spring. Therefore, there is an advantage that smooth opening and closing can be realized and that the service life can be improved by preventing the valve plate from being damaged.

  According to the present invention, as described above, since the spring is composed of a ring-shaped disc spring, any inclination in the lateral direction (circumferential direction) of the valve plate is corrected to correct the inclination. Since the plate can be adjusted to an appropriate position, there is an advantage that smooth opening and closing can be ensured and damage to the valve plate can be suppressed.

  According to the present invention, as described above, when the valve plate is in the closed position, the portion positioned in the opening is formed thinner than the other portions by, for example, cutting both the front and back surfaces. Therefore, the valve plate can be reduced in weight, and there is an actual benefit that can be appropriately achieved at high speed.

  According to the present invention, as described above, since the motor and the power transmission means are detachably connected to the valve plate, there is an advantage that maintenance and replacement such as maintenance and repair can be easily performed.

It is a schematic sectional drawing in the open position of the vacuum gate valve of this invention. It is a disassembled perspective view of the power transmission means used for this invention. It is sectional drawing of a power transmission means when the valve plate used for this invention exists in an open position. It is sectional drawing of a power transmission means when the valve plate used for this invention exists in a closed position.

  An embodiment for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 shows a vacuum gate valve 10 according to the present invention. And a suction pump (not shown) for evacuating the inside of the processing chamber, and used to seal and keep the inside of the processing chamber in a vacuum.

  As shown in FIG. 2, the vacuum gate valve 10 of the present invention includes a casing 12 having an opening 12A, a valve plate 14 that swings in the casing 12 to open and close the opening 12A, and the valve plate 14 includes A motor 16 for driving and a power transmission means 18 for transmitting the power of the rotating shaft 16A of the motor 16 to the valve plate 14 are provided.

(1. Power transmission means)
In the present invention, as shown in FIGS. 1 to 4, the power transmission means 18 directly transmits the power of the rotating shaft 16A of the motor 16 to the valve plate 14 coaxially without using a gear. Accordingly, the driving force of the motor 16 can be directly transmitted to the valve plate 14, and the valve plate 14 can be opened and closed at an ultra-high speed of about 0.3 seconds. At the same time, the number of parts is reduced because no gears are used, and deterioration due to collision that occurs during meshing can be suppressed, so that the service life can be dramatically improved.

  Specifically, as shown in FIGS. 1 to 4, the power transmission means 18 is connected to a rotating shaft 16A of the motor 16 and rotates together with the rotating shaft 16A. The flange 20 and the valve plate 14 A rotating body 22 that rotates together with the flange 20 and a spring 24 that biases the rotating body 22 in a direction in which the valve plate 14 connected to the rotating body 22 moves away from the opening 12A of the casing 12. Yes.

  As shown particularly in FIGS. 2 to 4, the flange 20 includes a coupling flange portion 20A directly coupled to the rotating shaft 16A of the motor 16, a shaft flange portion 20B coupled to the coupling flange portion 20A, and a coupling flange portion 20A. And an uneven coupling leaf spring 20C sandwiched between the shaft flange portion 20B and the shaft flange portion 20B. With this flange 20, the rotational force of the rotating shaft 16A of the motor 16 can be transmitted coaxially to the valve plate 14 without using a gear, and the valve plate 14 can be swung at a high speed. The coupling leaf spring 20C bears a buffering action during driving between the coupling flange portion 20A and the shaft flange portion 20B.

  As shown particularly in FIGS. 2 to 4, the rotating body 22 has a substantially piece-like shape having a main body portion 22 </ b> A and a shaft portion 22 </ b> B extending from the main body portion 22 </ b> A and connected to the valve plate 14. As shown in FIGS. 2 to 4, the rotating body 22 is installed in a cover 26 fixed to the casing 12, and the cover 26 covers the lateral direction and the vertical direction. As shown in FIGS. 2 to 4, the main body portion 22A of the rotating body 22 is disposed above and below the main body portion 22A in the vertical direction through the roller bearing 28, as shown in FIGS. By being held via the two thrust bearings 30A and 30B with the washer 30a arranged, the cover 26 is rotatably installed. As described above, the rotating body 22 is rotatably held by the bearings 28, 30A, and 30B having a small friction coefficient. Therefore, unlike the case of using a gear or the like, the rotating body 22 has little deterioration over time, and ensures a sufficient driving force. The service life can be improved, and the rotating body 22 can be rotated without runout.

  2 and 3, a part (tip) of the shaft flange portion 20B of the flange 20 is inserted into the cover 26, and the rotating body 22 is attached to the flange 20 within the cover 26. It is connected and can rotate with the flange 20 by the rotation of the flange 20. In this case, as shown in FIGS. 2 to 4, the thrust bearings 30 </ b> A and 30 </ b> B are formed in a ring shape so as to cover the periphery of the shaft flange portion 20 </ b> B of the flange 20 and the upper surface portion and the bottom surface portion of the main body portion 22 </ b> A of the rotating body 22. Be placed. On the other hand, as shown in FIGS. 2 to 4, the roller bearing 28 includes a ring-shaped frame 28 </ b> A disposed around the main body 22 </ b> A of the rotating body 22 and a plurality of adjacent frames disposed in the frame 28 </ b> A. It consists of a rod-shaped roller 28. Further, as shown in FIGS. 2 and 3, the shaft portion 22 </ b> B of the rotating body 22 is held in the casing 12 via an O-ring casing 32.

  As shown in FIGS. 2 to 4, the spring 24 is installed between the main body portion 22 </ b> A of the rotating body 22 and the thrust bearing 30 </ b> A on the flange 20 side of the rotating body 22. As the spring 24, it is preferable to use a ring-shaped disc spring arranged around the shaft flange portion 20 </ b> B of the flange 20 as shown in FIGS. 2 to 4.

  In the free state, the spring 24 moves in a direction in which the valve plate 14 connected to the rotating body 22 is separated from the opening 12A of the casing 12 (in FIG. 1 and FIG. 3, the rotating body 22 is pushed upward). The rotating body 22 is energized. Therefore, in the open position where no mechanical load is applied to the valve plate 14 for sealing, a gap is generated between the rotor 22 and the thrust bearing 30A on the valve plate 14 side, as shown in FIG. 1, the valve plate 14 is lifted and urged away from the casing 12, as shown in FIG.

  Therefore, for example, when a force in the direction of the casing 12 (downward in FIGS. 1 and 3) is applied to the valve plate 14 by atmospheric pressure, vibration, or the like, the valve plate 14 does not go through the spring 24 unlike the present invention. In contrast, the root portion of the valve plate 14 remains fixed (clamped) and gradually warps as it goes to the tip. In the present invention, since the spring 24 receives and absorbs the displacement in the vertical direction including the root portion of the valve plate 14 and attempts to restore the valve plate 14 to its original position by the urging force, the valve plate 14 Can be adjusted to a predetermined position. For this reason, even if the valve plate 14 swings at a high speed to generate vibrations or the pressure difference between the front and back of the valve plate 14 is severe, the valve plate 14 is adjusted to a predetermined position to be shaken appropriately. Can be moved. At the same time, breakage and deformation of the valve plate 14 can be suppressed by the pressure unnaturally applied to the valve plate 14.

  On the other hand, the valve plate 14 is mechanically brought into close contact with the casing 12 against the urging force of the spring 24 by the isolation means 36 shown in FIG. 3, the rotating body 22 is allowed to be displaced toward the casing 12 (downward in FIGS. 1 and 4) using the spring 24 as a buffer member, as shown in FIG. 3, and the rotating body 22 and the thrust bearing 30 </ b> A A gap is formed between them, and the sealed state can be maintained. Even during this sealing, the valve plate 14 receives pressure over a wide range from the atmospheric pressure side, and may be warped so as to swell downward in FIG. 1, for example. Therefore, it is possible to reduce the shearing force due to warpage and suppress unnatural stress and prevent damage to the valve plate 14.

  Further, when the valve plate is opened and closed (at the time of swinging), the motive force of the spring 24 causes the power transmission means 18 to place a gap between the valve plate 14 and the casing 12 as shown in FIGS. Can be swung while being held. Therefore, even if the valve plate 14 is opened and closed at a high speed, the valve plate 14 does not collide with or come into contact with the casing 12 and can be smoothly opened and closed. The number of years can be improved.

  Further, since the spring 24 is formed of a ring-shaped disc spring, the inclination of the valve plate 14 in all directions in the lateral direction (circumferential direction) can be corrected. That is, for example, the tilt occurred in the direction connecting the root portion and the tip of the valve plate 14 (the left-right direction in FIGS. 1 and 2) and the direction perpendicular to this (the depth direction in FIGS. 1 and 2). In any of the inclinations, the spring portion located on the upper end side of the inclination is compressed, and the spring portion located on the lower end side of the inclination is stretched to receive the inclination of the valve plate 14, while the restoring force causes the valve plate to 14 can be returned to the original horizontal position to adjust the valve plate 14 to an appropriate position, and the valve plate 14 can be smoothly opened and closed. Damage can be suppressed.

(2. Valve plate)
In the present invention, as shown in FIG. 1, the valve plate 14 is formed such that the portion located in the opening 12 </ b> A is thinner than the other portions when in the closed position. Thereby, weight reduction of the valve plate 14 can be achieved and it can be set as the valve plate 14 suitable for the opening and closing at high speed. In this case, as shown in FIG. 1, it is possible to cut only the surface on the chamber side that is evacuated, or to thin the front and back surfaces of the valve plate 14 by cutting.

  In order to reduce the weight, the valve plate 14 is preferably made of aluminum. As described above, even if the thickness and weight are reduced, in the present invention, the spring 24 of the power transmission means 18 absorbs the displacement and deformation of the valve plate 24, so that sufficient durability is ensured. Can do.

(3. Detachment)
Furthermore, in the present invention, the motor 16 and the power transmission means 18 are detachably connected to the valve plate 14. Specifically, as shown in FIG. 1, the valve plate and the rotating body 22 are connected by a screw 34, and by releasing the fixation by the connecting pin, the power transmission means 18, the motor 16, and the O-ring The casing 32 can be easily removed from the valve plate 14 and the casing 12. For this reason, maintenance and replacement such as maintenance and repair can be easily performed.

  In particular, the present invention can be widely applied 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.

DESCRIPTION OF SYMBOLS 10 Vacuum gate valve 12 Casing 12A Opening 14 Valve plate 16 Motor 16A Rotating shaft 18 Power transmission means 20 Flange 20A Connection flange part 20B Shaft flange part 20C Connection leaf spring 22 Rotating body 22A Main part 22B Shaft part 24 Spring 26 Cover 28 Roller Bearing 28A Frame 28A
28B Rod roller 30A, 30B Thrust bearing 30a Washer 32 O-ring casing 34 Screw

Claims (6)

In a vacuum gate valve comprising a casing having an opening, a valve plate that swings within the casing to open and close the opening, and a motor that drives the valve plate, the power of the rotating shaft of the motor is geared. A vacuum gate valve further having power transmission means for transmitting directly to the valve plate on the same axis without being interposed, the power transmission means being connected to a rotation shaft of the motor and rotating with the rotation shaft; A rotating body connected to the flange and the valve plate and rotating together with the flange, the rotating body having a main body portion and a shaft portion extending from the main body portion and connected to the valve plate, It is installed in a cover fixed to the casing, and is covered with the cover in the lateral direction and the vertical direction. The part can be freely rotated in the cover by being held via the roller bearing in the lateral direction and the two thrust bearings arranged above and below the main body in the vertical direction with respect to the cover. A gate valve for vacuum characterized by being installed in. 2. The vacuum gate valve according to claim 1, wherein the power transmission means includes a spring that urges the rotating body in a direction in which the valve plate connected to the rotating body is separated from the opening of the casing. The vacuum gate valve according to claim 1, further comprising a spring that absorbs a displacement in a vertical direction of the valve plate. 3. The vacuum gate valve according to claim 1, wherein the power transmission means holds the gap between the valve plate and the casing by an urging force of the spring. 4. A vacuum gate valve characterized by swinging. 4. The vacuum gate valve according to claim 2, wherein the spring is formed of a ring-shaped disc spring, and corrects inclination in all lateral directions of the valve plate. 5. Characteristic vacuum gate valve. 5. The vacuum gate valve according to claim 1, wherein when the valve plate is in a closed position, a portion located in the opening is formed thinner than other portions. This is a vacuum gate valve. 6. The vacuum gate valve according to claim 1, wherein the motor and the power transmission means are detachably connected to the valve plate. .

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