JP4578829B2 - Seal plate for vacuum gate valve and seal member used therefor - Google Patents

Description

  The present invention relates to a seal plate in a vacuum gate valve used in a semiconductor manufacturing apparatus or the like and a seal member used therefor.

  In semiconductor manufacturing such as silicon wafers, thin film manufacturing, liquid crystal manufacturing, and the like, processing and processing of workpieces such as ion plating and plasma etching are performed in a high environment under a clean environment.

  By the way, a bonded seal is known as a sealing device for a gate opening which serves as a work loading / unloading section. In the bonded seal, a sealing member such as fluororubber is bonded to a flat plate formed of a metal such as aluminum.

  Such a bonded seal has, for example, higher sealing performance and repeated opening / closing operability than a conventional sealing device (Patent Document 1) in which a sealing member is simply installed in a dovetail formed in a plate body. It has the advantage of being excellent.

  FIG. 7 shows a conventional bonded seal 6 employed in, for example, a wafer loading / unloading gate opening 16 between the process chamber 2 and the transfer chamber 4 in the semiconductor manufacturing apparatus.

  The bonded seal 6 includes a metal plate main body 8 formed in a substantially rectangular shape and a seal member 10 made of an elastic material bonded to the outer peripheral portion of the plate main body 8. In addition, the plate body 8 is fixed to a base 12 having a substantially L-shaped cross section, and, for example, a single shaft 14 that moves in the vertical direction is attached to the center of the base 12 in the longitudinal direction. Yes.

  In such a bonded seal 6, when the gate 14 is opened and closed simply by moving the shaft 14 in the vertical direction, the plate body 8 and the like are scratched by sliding, which causes generation of metal particles. For this reason, the plate body 8 is once moved back to the left in the figure and then moved in the vertical direction. That is, in order to close the gate opening 16 in the open state, the shaft 14 in the lower position is first moved in the direction of the arrow X, and then the plate body 8 is moved in the direction of the arrow Y, thereby The seal member 10 is pressed against the valve seat surface 18 formed on the outer peripheral portion of the portion 16 to seal the inside of the process chamber 2.

  By the way, in such a bonded seal 6, the shaft 14 is attached to a substantially middle portion in the longitudinal direction of the plate body 8, and the plate body 8 is supported by the shaft 14, so that the central region where the shaft 14 is attached is provided. A concentrated load acts in the vicinity of Q.

  Therefore, when the gate opening 16 is closed, that is, when a large tightening pressure is applied in the direction of the arrow Y, warpage occurs in the vicinity of the end regions R and S of the plate body 8, and as a result, both ends The seal pressure in the partial areas R and S becomes weak, and there is a risk of leak leakage. In order to avoid this, both end regions R and S of the plate body 8 are formed to be curved, and measures are taken to absorb warpage of the plate body 8 due to a tightening load in the Y direction. It has been troublesome to bend the plate body 8 precisely, and there is a problem that the cost is increased.

On the other hand, in the conventional structure, a concentrated load acts on the central region Q to which the shaft 14 is attached. Therefore, concentrated stress is generated in the seal member 10 located in the central region Q, and the adhesive at this position There was also a risk of peeling.
JP 10-318373 A

  In the present invention, in view of the above-described conventional problems, even when a concentrated load is applied to a central region supported by a shaft in a bonded seal used in a semiconductor manufacturing apparatus or the like, for example, leak leakage occurs. There is provided a seal plate for a vacuum gate valve and a seal member used for the seal plate, which can ensure a stable sealing performance for a long period of time without fear of peeling of the adhesive in the central region. The purpose is that.

The seal plate in the vacuum gate valve according to the present invention is:
A valve body that closes or opens the gate opening by contacting or separating from the substantially rectangular gate opening is a seal plate in a vacuum gate valve supported by a drive shaft that moves substantially linearly. There,
A plate body formed in a substantially flat plate shape and having a sealing member mounting groove formed on a flat plate portion facing a valve seat surface formed on an outer peripheral edge of the gate opening;
A circumferential annular seal member mounted in the seal member mounting groove of the plate body,
A central region of the plate body near the drive shaft of the plate body,
One end side of the plate main body on one end side away from the central region,
When the other end side away from the central region is divided as the other end region of the plate body,
In the central region of the plate body, the projection height of the seal member toward the valve seat surface is the lowest,
From this central region, the protruding height of the seal member is set in advance so as to approach the one end region and the other end region.

  The seal plate in the vacuum gate valve having such a structure is previously provided with a height that protrudes toward the valve seat of the seal member in both end regions that are susceptible to warpage, and a surface pressure that abuts the valve seat surface is a central region. Occurrence of leakage leakage is prevented.

In addition, since it is not a metal seal plate that is processed but a seal member made of, for example, an elastic material that is bonded to the metal seal plate, the processing cost is extremely low.
Further, in the present invention, the difference between the protruding height of the seal member toward the valve seat surface in the central region and the height of the seal member toward the valve seat surface in both end regions is d,
When the length in the longitudinal direction of the gate opening is Z,
When 100 mm ≦ Z ≦ 400 mm, the range is preferably 0.1 mm ≦ d ≦ 0.5 mm.

  If the height difference d is set in such a range, even if there is an error in dimensional accuracy in a normal use state, or even when the seal plate is warped, It was confirmed that the error could be absorbed and no leak leakage occurred.

Furthermore, the sealing member according to the present invention is:
A circumferential annular seal member made of an elastic material used for a seat plate in the vacuum gate valve described above,
The seal member joined in the substantially rectangular seal member mounting groove has a cross-sectional shape of a bottom side joined to the bottom surface of the seal member mounting groove and an inner side joined to the inner side surface of the seal member mounting groove. A side, an arcuate protrusion that protrudes from the plate body toward the valve seat surface, contacts and separates from the valve seat surface, and is positioned on one hem portion of the arcuate protrusion and outside the seal member mounting groove. An outer inclined side to be arranged, and an inner inclined side located at the other hem portion of the arcuate protrusion and arranged inside the seal member mounting groove,
The projecting height of the seal member disposed in both end regions of the seal member mounting groove of the seat plate toward the valve seat surface side is defined as the projecting height of the seal member disposed in the center region of the seat plate. Is set to be higher and continuously changing from both end regions to the central region, and the rate of change is
When the difference between the projecting height of the seal member in the central region and the projecting height of the seal member in both end regions is d, and the length in the longitudinal direction of the gate opening is Z,
When 100 mm ≦ Z ≦ 400 mm, the range is 0.1 mm ≦ d ≦ 0.5 mm.

  According to the sealing member having such a configuration, it can be preferably used as a sealing member for a vacuum gate plate.

  According to the seal plate in the vacuum gate valve according to the present invention, the metal plate body made of aluminum or the like is usually not processed, but, for example, only the seal member formed of an elastic material is processed. Since it is good, processability is good and it can be manufactured at low cost.

In addition, since the contact pressure of the gate opening with respect to the valve seat surface is substantially the same between the center region and both end regions, it is possible to prevent leak leakage.
In addition, by setting the difference in the protruding height of the seal member as described above, it was possible to correct deformation due to warping of the seal plate and effectively prevent leakage.

  Furthermore, the sealing member according to the present invention can be effectively used as a sealing member for a vacuum gate valve.

Hereinafter, embodiments of the present invention shown in the drawings will be described.
FIG. 1 shows a main part of a seal plate in a vacuum gate valve according to an embodiment of the present invention. 2 is a schematic front view of the end region on the opposite side of the bonded seal shown in FIG. 1, and FIG. 3 is an enlarged sectional view in the direction of the line AA in FIG.

  The bonded seal 40 shown in FIG. 1 corresponds to the bonded seal 6 shown in FIG. That is, the plate body 20 shown in FIG. 1 is formed of a metal such as aluminum and is formed in a rectangular shape that is long in the left-right direction corresponding to the opening. For example, the overall horizontal length M is 354 mm, The length N is set to 65 mm, and the thickness P is set to 25 mm.

  As shown in an enlarged view in FIG. 3, a seal member mounting groove 22 having a L-shaped cross section and a single groove shape is formed on the outer peripheral edge of the plate body 20. A seal member 24 formed of an elastic material is bonded to the seal member mounting groove 22 with an adhesive.

The seal member 24 is in a natural state and has a belt-like shape, and is adjusted to have an annular shape by being mounted in the seal member mounting groove 22.
Specifically, the seal member 24 is made of fluorine-based rubber. A material having excellent functions such as plasma resistance, heat resistance, and vacuum resistance can be selected and used in accordance with the use environment.

  As shown in FIGS. 3 and 4, the cross-sectional shape of the seal member 24 is a substantially triangular shape, and a bottom side 24 a joined to the bottom surface of the seal member mounting groove 22 and an inner side joined to the inner side surface of the mounting groove 22. The side 24b, an arcuate protrusion 24c that protrudes from the front surface of the plate body 20 toward the valve seat surface, and the open side of the seal member mounting groove 22 on the left side of the arcuate protrusion 24c in FIGS. The outer inclined side 24d is disposed, and the inner inclined side 24e is disposed on the right side of the arcuate protrusion and inside the seal member mounting groove 22.

  The overall cross-sectional shape of the seal member 24 is formed as described above, but the seal member 24 is formed so that the protruding height toward the valve seat surface 18 side differs depending on the mounting position with respect to the plate body 20. Has been.

  That is, the plate body 20 has a rectangular shape that is long in the lateral direction. For example, as shown in FIGS. 1, 2, and 5, the center region Q of the plate body is located near the center to which the shaft 14 is attached. When one end portion side away from the region Q is one end region R of the plate body and the other end portion side is the other end region S, the center region Q protrudes from the bottom 24a of the seal member 24. As shown by the solid line in FIG. 4, the height T ′ is set lower than the protruding height T (broken line) in both end regions R and S. That is, when the seal member 24 is viewed from the upper side in FIG. 1, as shown in FIG. 5, the height T ′ is the lowest in the central region Q and is increased as the end regions R and S are approached. Yes. When the difference in height between the central region Q and the end regions R and S is represented by d, the difference in height d is the length Z (in the longitudinal direction of the gate opening 16 shown in FIG. 1 is adjusted as appropriate according to the length M of the plate body 20 in FIG. In the embodiment, the height difference d is set to 0.2 mm.

  In the present invention, when the length of the gate opening in the longitudinal direction is Z, when this Z is in the range of 100 mm to 400 mm, the height difference d may be about 0.1 mm to 0.5 mm. preferable. Further, between the central region Q and both the end regions R and S, the height difference d continuously changes as shown in FIG.

The reason for setting the height difference d in this way is as follows.
That is, FIG. 6 shows the amount of warpage of a conventional bonded seal having a shaft 14 at the center of a rectangular plate body 20 measured by FEA analysis.

  As is apparent from this analysis result, it was found that a warp of 0.2 mm at the maximum occurred between the plate center and both ends. Therefore, the height difference d is set corresponding to such a warp amount. The height difference d was set in such a range, and the surface pressure distribution in the seal top portion (arc-shaped protrusion 24c) of the seal member 24 was measured by FEA analysis. By this FEA analysis, it was confirmed that the surface pressure distribution in the center region Q and the end regions R and S is substantially constant.

Table 1 shows the results of an experiment in which a seal member having the same size as that used in the FEA analysis was used as a sample and a seal test and a peel test were performed.
As the gate valve to which the seal member is attached, the gate valve shown in FIG. 1 is adopted, and the pressing load in the Y direction is 3000 N. In the seal test, He gas leakage was measured at room temperature.

Furthermore, as a peeling test, the temperature of the plate body 20 was set to 150 ° C., and the opening / closing operation was performed 100 times to confirm peeling. By these tests, the characteristics of the bonded seals using the respective seal members are shown in the table. The shape of Comparative Example 1 has no height difference d, and Comparative Example 2 does not process the seal member but curves the metal plate body 20.

As can be understood from Table 1, the sample according to this example was good in terms of sealing performance, peelability and cost.
As described above, according to the present embodiment, it is only necessary to process the sealing member made of an elastic material, so that the complexity of processing is not required, and it can be manufactured at low cost.

As described above, according to the seal plate in the vacuum gate valve according to the embodiment of the present invention, by correcting the warp generated around the vicinity supported by the shaft by the protruding height of the seal member, The seal surface pressure in both end regions can be made substantially constant. As a result, leak leakage could be prevented.
As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example at all.

  For example, in the above embodiment, the seal member used in the gate opening suitable for putting in and out the wear having a diameter of 300 mm and the seal plate on which the seal member is mounted have been described. The present invention can also be applied to a gate valve having a gate opening.

The cross-sectional shape of the gate opening is not limited to a rectangle, and any shape may be used as long as the left-right direction is longer than the vertical direction.
Furthermore, in the above-described embodiment, the case where a single shaft is attached to the plate body 20 has been described as an example. However, the present invention can also be applied to a gate valve that supports the plate body 20 with two shafts.

  Furthermore, in the said Example, although the sealing member mounting groove | channel 22 by which one side was open | released outward is illustrated, this mounting groove can be applied even if it is a U-shaped cross section, ie, a both-groove type. .

FIG. 1 is a schematic perspective view of a bonded seal according to an embodiment of the present invention. FIG. 2 is a front view showing an end region on the opposite side of the bonded seal in FIG. FIG. 3 is an enlarged cross-sectional view in the AA line direction in FIG. 4 is an enlarged cross-sectional view of the seal member shown in FIG. FIG. 5 is a schematic top view of the seal member shown in FIG. 1 when viewed from above in FIG. FIG. 6 shows the experimental results of measuring the amount of warpage of the plate body by FEA analysis. FIG. 7 is a cross-sectional view of a seal portion employing a conventional bonded seal.

Explanation of symbols

6 Bonded seal 8 Plate body 14 Drive shaft 16 Gate opening 18 Valve seat surface 20 Plate body 22 Seal member mounting groove 24 Seal member 24a Bottom side 24b Inner side 24c Arc-like protrusion 24d Outer inclined side 24e Inner inclined side Q Central region R One end region S The other end region Z Length of gate opening in longitudinal direction d Difference in height

Claims (3)

A valve body that closes or opens the gate opening by contacting or separating from the substantially rectangular gate opening is a seal plate in a vacuum gate valve supported by a drive shaft that moves substantially linearly. There,
A plate that is formed in a substantially flat plate shape and has a substantially L-shaped cross-section and a single groove-like seal member mounting groove formed on the outer peripheral edge of a flat plate portion that faces the valve seat surface formed on the outer peripheral edge of the gate opening. The body,
A circumferential annular seal member mounted in the seal member mounting groove of the plate body,
A central region of the plate body near the drive shaft of the plate body,
One end side of the plate main body on one end side away from the central region,
When the other end side away from the central region is divided as the other end region of the plate body,
In the central region of the plate body, the projection height of the seal member toward the valve seat surface is the lowest,
From the central region, as the one end region and the other end region are approached, the protruding height of the seal member is set in advance so as to gradually increase ,
In the cross-sectional shape of the seal member, the bottom side joined to the bottom surface of the seal member mounting groove, the inner side joined to the inner side surface of the seal member mounting groove, and the plate body toward the valve seat surface. An arcuate protrusion that protrudes in contact with and separates from the valve seat surface, an outer inclined side that is located on one hem portion of the arcuate protrusion and is disposed outside the seal member mounting groove, and an arcuate protrusion of the arcuate protrusion An inner inclined side located at the other hem portion and disposed inside the seal member mounting groove, and the inner inclined side and the inner side are connected by a horizontal portion extending substantially horizontally, The seal plate in a vacuum gate valve, wherein the bottom side and the outer inclined side are connected by an outer side extending substantially vertically. The difference between the protruding height of the seal member toward the valve seat surface in the central region and the height of the seal member toward the valve seat surface in both end regions is d,
When the length in the longitudinal direction of the gate opening is Z,
2. The seal plate for a vacuum gate valve according to claim 1, wherein when 100 mm ≦ Z ≦ 400 mm, the range is 0.1 mm ≦ d ≦ 0.5 mm. A circumferential annular seal member made of an elastic material used for a seat plate in the vacuum gate valve according to claim 1 or 2,
Said sealing member to be joined to the substantially L-shaped cross section with strip groove-shaped sealing member fitting groove, the cross-sectional shape, a base joined to the bottom surface of the sealing member fitting groove, of the sealing member fitting groove An inner side joined to a side surface, an arc-shaped projecting portion projecting from the plate body toward the valve seat surface and contacting and separating from the valve seat surface; and the seal located at one hem portion of the arc-shaped projecting portion An outer inclined side disposed on the outer side of the member mounting groove, and an inner inclined side positioned on the other hem portion of the arcuate protrusion and disposed on the inner side of the sealing member mounting groove, and the inner inclined side; The inner side is connected by a horizontal part extending substantially horizontally, and the bottom side and the outer inclined side are connected by an outer side extending substantially vertically,
The projecting height of the seal member disposed in both end regions of the seal member mounting groove of the seat plate toward the valve seat surface side is defined as the projecting height of the seal member disposed in the center region of the seat plate. Is set to be higher and continuously changing from both end regions to the central region, and the rate of change is
When the difference between the projecting height of the seal member in the central region and the projecting height of the seal member in both end regions is d, and the length in the longitudinal direction of the gate opening is Z,
A seal member for a seal plate, wherein when 100 mm ≦ Z ≦ 400 mm, the range is 0.1 mm ≦ d ≦ 0.5 mm.

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