JP2019173771A - Gas filter and gas supply device including the same - Google Patents

Abstract

To provide a gas filter which can prevent gas leakage near a gasket, and to provide a gas supply device.SOLUTION: A gas filter 1 includes: a metallic base plate 2 formed with a first through hole 4 through which gas can pass; and a filter 3 which is joined to the base plate 2 so as to purify the gas G that has passed through the first through hole 4. A filter arrangement part 7 which is formed so as to enclose the first through hole and to which the filter 3 is attached and a gasket arrangement part 8 which is formed so as to enclose the filter arrangement part 7 and used to attach the gasket are formed around the first through hole 4 of the base plate 2. The filter 3 has a cylindrical shape protruding from the base plate 2 in a first direction A and its base plate side end part 3a is welded to the filter arrangement part 7. Vickers hardness of the gasket arrangement part 8 is larger than vickers hardness of the filter arrangement part 7.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a gas filter and a gas supply apparatus that can be suitably used, for example, in a semiconductor device manufacturing apparatus.

  For example, in a semiconductor device manufacturing process, various gases are used in film formation, etching, cleaning, and the like. These gases must not contain particles. This is because when foreign matter adheres to the wafer surface, the wiring of the semiconductor device is short-circuited, and the yield of the semiconductor device is reduced.

  The following Patent Document 1 is housed in the housing as a gas filter used in the gas supply device, and a housing having two flow ports through which gas flows, and so as to isolate each flow port, What is provided with the filter member which capture | acquires the particle | grains in the gas which flowed in from one through-flow port is described.

JP 2009-240984 A

  By the way, this type of gas filter has a demand for miniaturization and simplification of the structure. As such a gas filter, the present inventors welded and joined a metal base plate having a through-hole through which a gas can pass and a filter for cleaning the gas that has passed through the through-hole to the base plate. A prototype gas filter was made.

  However, in the gas filter, the metal composition around the welded portion of the base plate may be denatured due to the heat effect during welding. This tendency is particularly strong when the thickness of the base plate is small. For this reason, if a gasket or the like for preventing gas leakage is placed near the filter and brought into contact with the base plate with a large pressure, the portion of the base plate may be deformed or cracked, and gas leakage may occur from the vicinity of the gasket. It was.

  The present invention has been devised in view of the above problems, and has as its main purpose to effectively suppress gas leakage from the vicinity of a gasket in a gas filter in which a filter is welded to a base plate.

  The present invention is a gas filter, which is a metal base plate having a first through-hole through which a gas can pass, and is joined to the base plate so as to clean the gas that has passed through the first through-hole. Including a filter, and is formed around the first through hole of the base plate so as to surround the first through hole, and to form a filter arrangement part for attaching the filter, and to surround the filter arrangement part And a gasket arrangement part for attaching a gasket is formed, the filter protrudes from the base plate in a first direction, and an end of the base plate side is formed in the filter arrangement part. It is welded, and the Vickers hardness of the gasket arrangement part is larger than the Vickers hardness of the filter arrangement part. To have.

  In another aspect of the present invention, a second through hole different from the first through hole may be formed in the base plate.

  In another aspect of the present invention, the gasket placement portion may include a first gasket placement portion provided on a first surface that is a surface of the base plate in the first direction.

  In another aspect of the invention, the first gasket placement portion may be continuous with the filter placement portion through a step.

  In another aspect of the present invention, the gasket placement portion may include a second gasket placement portion provided on a second surface that is a surface opposite to the first direction of the base plate.

  In another aspect of the present invention, in the cross section of the base plate, the filter placement portion may have a tapered shape with a thickness gradually decreasing toward the center of the first through hole.

  In another aspect of the present invention, the gasket placement portion may have a Vickers hardness of 170 ° or more.

  In another aspect of the present invention, it is desirable that the Vickers hardness of the gasket arrangement part is 20 HV points or more larger than the Vickers hardness of the filter arrangement part.

  In another aspect of the present invention, the filter may be tapered in the first direction.

  In another aspect of the present invention, the base plate may have a thickness of 2.0 to 5.0 mm.

  In another aspect of the present invention, the gas supply device is configured by arranging the gas filter according to any one of the above in the middle of the supply path for supplying the gas.

  In the gas filter of the present invention, the end of the base plate side of the filter is welded to the filter placement portion. Therefore, the gas filter of the present invention can be provided easily and inexpensively.

  Moreover, the gas filter of this invention is comprised so that the Vickers hardness of the gasket arrangement | positioning part formed so that a filter arrangement | positioning part may be surrounded is larger than the Vickers hardness of a filter arrangement | positioning part. Therefore, even when the gasket placement part receives a large pressure from the gasket placed there, damage or deformation of the gasket placement part is suppressed, and consequently, gas leakage from the vicinity of the gasket is suppressed over a long period of time. can do.

It is a perspective view of a gas filter concerning one embodiment of the present invention. It is a top view of the gas filter concerning one embodiment of the present invention. It is the sectional view on the AA line of FIG. It is a principal part expanded end view of FIG. It is a fragmentary sectional view of the gas supply apparatus using the gas filter of this embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The drawings are used for the purpose of illustrating and explaining the present invention, and the present invention should not be construed as being limited to the specific forms shown in the drawings. In addition, the scale, balance, and the like of the devices shown in the drawings are not unified throughout the drawings, and may be exaggerated in part to help understand the configuration. Moreover, the same number is attached | subjected to the same or common element through all embodiment, and the overlapping description may be abbreviate | omitted.

[Overall configuration of gas filter]
1 and 2 show a perspective view and a plan view of the gas filter 1 of the present embodiment, respectively, and FIG. 3 shows a cross-sectional view taken along line AA of FIG. 1 to 3, the gas filter 1 includes a metal base plate 2 and a filter 3 joined to the base plate 2.

  A first through hole 4 is formed in the base plate 2, and the filter 3 is fixed to the base plate 2 so as to cover the first through hole 4. The filter 3 of the present embodiment protrudes from the base plate 2 in the first direction A.

[Base plate]
The base plate 2 is configured in a thin plate shape, for example. For convenience of explanation, the outermost surface facing the first direction A of the base plate 2 is a first surface 2a, and the outermost surface of the base plate 2 on the opposite side is a second surface 2b. In the present embodiment, the first surface 2a and the second surface 2b form a plane parallel to each other, but are not limited to such a mode.

  The base plate 2 can be made of various materials as long as it is a metal material. For example, various stainless steels such as SUS316L, nickel alloys (for example, Hastelloy (registered trademark of US Haynes)) or pure nickel are preferable. Adopted.

  The shape and thickness of the base plate 2 may be appropriately determined according to the gas supply device in which the gas filter 1 is used. In a preferred embodiment, in order to further reduce the size of the gas filter 1, the thickness t of the base plate 2 (that is, the shortest distance from the first surface 2a to the second surface 2b) is, for example, 2.0 to 5.0 mm. It is good to be selected by the range. Similarly, in order to reduce the size of the gas filter 1, the maximum dimension of the base plate 2 in a plan view (the diagonal dimension in FIG. 2) is preferably in the range of 25 to 50 mm, for example. It should be understood that all of the above dimensions are examples.

  In the present embodiment, the first through hole 4 is formed, for example, as a circular through hole in a plan view of the base plate 2. Further, the first through hole 4 is provided at substantially the center of the base plate 2 in a plan view of the base plate 2.

  In addition to the first through hole 4, for example, the second through hole 5 and a plurality of attachment holes 6 may be provided in the base plate 2.

  For example, the second through hole 5 is provided adjacent to the first through hole 4. The 2nd through-hole 5 can be utilized as a hole which can pass the gas G which passed the 1st through-hole 4 and the filter 3 in that order. For example, as shown in FIG. 3, after the gas G supplied from below the base plate 2 is filtered by the filter 3, the gas G is passed through the second through-hole 5 using a housing (not shown). Thus, it can be guided again below the base plate 2.

  The attachment holes 6 are provided, for example, around the base plate 2, and are provided at the four corners of the base plate 2 in this embodiment. Therefore, the gas filter 1 of the present embodiment can be detachably fixed to the gas supply device using the attachment hole 6 using a fixing tool such as a screw. For this reason, after the gas filter 1 is used for a certain time for a gas supply device (not shown) for the purpose of gas filtration, the gas filter 1 is removed from the gas supply device for cleaning, maintenance, and gas supply again. It can be used by mounting on the device. Therefore, the gas filter 1 of the present embodiment can be easily maintained and replaced.

  As shown in an enlarged view in FIG. 4, the base plate 2 further includes a filter arrangement portion 7 and a gasket arrangement portion 8 around the first through hole 4.

[Filter placement section]
The filter placement portion 7 is a portion formed so as to surround the first through hole 4 in order to attach the filter 3. The filter arrangement portion 7 of the present embodiment is formed in an annular shape adjacent to the first through hole 4. In other words, the filter placement portion 7 of the present embodiment can be grasped as an inner peripheral edge portion that defines the first through hole 4.

  The filter placement portion 7 includes a first surface 7 a on the first surface 2 a side of the base plate 2 and a second surface 7 b on the second surface 2 b side of the base plate 2.

  The first surface 7 a of the filter placement portion 7 is an annular surface and is located slightly behind the first surface 2 a of the base plate 2. In other words, the first surface 7a is located between the first surface 2a and the second surface 2b. The first surface 7a is formed by a plane substantially parallel to the first surface 2a (and the second surface 2b). In this embodiment, the edge part 3a of the filter 3 is mounted on the 1st surface 7a, for example, the edge by the side of the 1st through-hole 4 of the boundary part of both is welded. FIG. 4 shows the weld bead blacked out. For welding, various methods such as laser welding, TIG welding, or plasma welding may be employed.

  The second surface 7b of the filter placement portion 7 is also an annular surface, and is located closer to the second surface 2b than the first surface 2a of the base plate 2. Further, the second surface 7b of the present embodiment is formed of a conical surface whose inner diameter gradually decreases in the first direction A. The filter arrangement portion 7 of the present embodiment is formed in a tapered shape whose thickness gradually decreases toward the center of the first through hole 4 by a combination of the first surface 7a and the second surface 7b. Such a filter arrangement portion 7 provides a sufficient space for accessing the boundary between the filter 3 and the filter arrangement portion 7 when the filter 3 and the filter arrangement portion 7 are welded from the inner peripheral surface side thereof. To help improve.

[Gasket placement area]
The gasket placement portion 8 is formed on the outer peripheral side so as to surround the filter placement portion 7. The gasket arrangement portion 8 of this embodiment is formed in an annular shape adjacent to the filter arrangement portion 7. As shown in phantom lines in FIG. 4, the filter placement portion 7 is provided as a space for placing a ring-shaped gasket 10 (for example, a metal gasket having a C-shaped cross section and other metal gaskets). ing.

  The gasket placement portion 8 is provided, for example, on the first surface 2a side of the base plate 2 and / or the second surface 2b side of the base plate 2. In the present embodiment, as a preferable aspect, the first gasket arrangement portion 8A provided on the first surface 2a side of the base plate 2 and the second gasket arrangement portion 8B provided on the second surface 2b side of the base plate 2 are included. .

[First gasket placement section]
For example, the first gasket placement portion 8A is continuous with the filter placement portion 7 via a step 9. That is, the first gasket placement portion 8 </ b> A is continuous with the first surface 7 a of the filter placement portion 7 through the step 9 extending in the thickness direction of the base plate 2. The step 9 is preferably used for positioning when the filter 3 is fixed to the base plate 2. The first gasket placement portion 8A is configured as a recess mainly composed of an annular support surface 12 that receives a surface pressure from the gasket 10 and a side wall surface 13 that extends from the outer edge of the support surface 12 to the first surface 2a of the base plate 2. Yes.

[Second gasket placement section]
The second gasket placement portion 8B is provided continuously with the filter placement portion 7, for example. That is, the second gasket placement portion 8B is continuous from the end of the second surface 7b of the filter placement portion 7 in the plate surface direction of the base plate 2 without any step. The second gasket placement portion 8B is also configured as a recess mainly composed of an annular support surface 12 that receives a surface pressure from the gasket 10 and a side wall surface 13 that extends from the outer edge of the support surface 12 to the second surface 2b of the base plate 2. Yes.

As shown in FIG. 3, in the present embodiment, as a preferable aspect, the third gasket arrangement portion 20 </ b> A corresponding to the first gasket arrangement portion 8 </ b> A and the second gasket arrangement portion 8 </ b> B also around the second through hole 5. And the gasket arrangement | positioning part 20 containing the 4th gasket arrangement | positioning part 20B is formed.
[filter]
As shown in FIG. 3, the filter 3 of the present embodiment is configured in a cylindrical shape, for example, in which the end 3 a on the base plate 2 side is opened and the opposite end 3 b is closed. As described above, the end portion 3a of the filter 3 is fixed to the filter arrangement portion 7 of the base plate 2 by welding.

  The filter 3 is made of a metal material, for example, a sintered metal having many fine holes. The filter 3 of this embodiment is configured as a sintered body of the same metal fiber as the base plate 2 in order to form a good weld joint with the base plate 2, but if both can be welded together, The filter 3 may be configured using various materials.

[Usage of gas filter]
FIG. 5 shows a gas supply device 100 as a typical usage mode of the gas filter 1. The gas supply apparatus 100 according to this embodiment is a gas supply apparatus for manufacturing a semiconductor device, and includes, for example, a flow path block 102, the gas filter 1 according to this embodiment, and a gas processing device 104. .

  The flow path block 102 is formed by exposing the first port O1 and the second port O2 to the outside. The first port O1 and the second port O2 communicate with a first flow path R1 and a second flow path R2 that extend through the flow path block 102, respectively.

  In the gas supply device 100, the gas filter 1 according to the present embodiment is configured such that the first through hole 4 communicates with the first port O1 and the second through hole 5 communicates with the second port O2, respectively. It is fixed with screws 114. As shown in black in FIG. 5, the gasket 10 is attached to each of the first gasket arrangement portion 8 </ b> A and the second gasket arrangement portion 8 </ b> B.

  The gas processing device 104 of the present embodiment includes, for example, a base plate 106, a first flow path block 108, a gas control device 110, and a second flow path block 112.

  For example, the base plate 106 is disposed so as to overlap the base plate 2 of the gas filter 1, and both are fixed to the flow path block 102 with screws 114. The base plate 106 is formed with a third through hole O3 through which the filter 3 can pass, and a fourth through hole O4 is formed so as to communicate with the second through hole 5 of the base plate 2.

  For example, the first flow path block 108 is formed in a cylindrical shape having a constant inner diameter so as to cover the filter 3, and a lower end side thereof is integrally fixed to the base plate 106. Therefore, the gas that has passed through the filter 3 passes through the space between the filter 3 and the first flow path block 108 and is sent to the gas control device 110. When the filter 3 is configured to be tapered toward the first direction A as in the present embodiment, the space between the filter 3 and the first flow path block 108 is downstream of the flow of the gas G. This is preferable from the viewpoint of improving the gas flow characteristics in the first flow path block 108.

  The gas control device 110 is, for example, a device such as a regulator or a mass flow, and performs predetermined processing and operation on the gas sent from the first flow path block 108 and supplies the gas to the second flow path block 112. To do.

  For example, the second flow path block 112 is configured in a cylindrical shape so as to cover the second through hole 5, and the lower end side thereof is integrally fixed to the base plate 106.

  In the gas supply device 100 as described above, the gas G supplied from the first flow path R1 of the flow path block 102 is removed from the first flow path block 1 after the particles are removed by the filter 3 through the first through hole 4. 108, the gas control device 110, the second flow path block 112, the fourth through hole O4, the second through hole 5, and the second port O2, and is taken out from the second flow path R2. Further, in this apparatus 100, the base plate 2 is sandwiched between the flow path block 102 and the base plate 106, so that gaskets are provided between the base plates 2 and 106 and between the base plate 2 and the flow path block 102, respectively. 10 is in contact with the gasket arrangement portion 8 with a high pressure, and an effect that gas leakage from the first through hole 4 and the second through hole 5 is prevented is expected. Moreover, size reduction of the gas supply apparatus 100 can be achieved by using the gas filter 1 of this embodiment.

[Vickers hardness of base plate]
In the gas filter 31 as in the present embodiment, when the base plate 2 and the filter 3 are welded and fixed, the periphery of the welded portion of the base plate 2 is easily affected by heat during welding and the metal structure is easily denatured. When such a metal structure modification occurs in the gasket placement portion 8 located in the vicinity of the filter 3, due to a high contact surface pressure with the gasket 10, the gasket placement portion 8 or the like is deformed or cracked, and gas leakage occurs. There is a fear.

  In view of the above situation, the gas filter 1 of the present embodiment is configured such that the Vickers hardness of the gasket arrangement portion 8 of the base plate 2 is larger than the Vickers hardness of the filter arrangement portion 7. For this reason, the gasket arrangement | positioning part 8 has high surface strength. Therefore, even when the gasket placement portion 8 comes into contact with the gasket 10 with a large pressure, deformation (plastic deformation), cracks and the like of the gasket placement portion 8 are suppressed, and as a result, the sealing performance is maintained for a long time from the vicinity of the gasket. Gas leakage can be prevented.

  In this specification, the Vickers hardness of the filter arrangement part 7 is measured at a plurality of places (for example, four places around the first through hole 4) in the filter arrangement part 7 excluding the weld bead. Means the highest value.

  Similarly, in the present specification, the Vickers hardness of the gasket arrangement portion 8 is the highest value measured at a plurality of locations (for example, four locations around the first through hole 4) at the gasket arrangement portion 8. means. Moreover, when the gasket arrangement | positioning part 8 has a surface of a some direction, it shall measure on the surface (this embodiment support surface 12) which receives the largest surface pressure from the gasket 10. FIG. Further, at each measurement point, the Vickers hardness is measured in accordance with JIS Z2244 (2009) under the condition of a test force of 0.2 kgf and the test direction as a direction perpendicular to the measurement surface.

  In order to exhibit the above-described action more effectively, the Vickers hardness of the gasket placement portion 8 is preferably 170 HV or higher, more preferably 300 HV or higher. On the other hand, the Vickers hardness of the filter placement portion 7 is preferably 150 HV or less in order to improve the welding workability of the filter 3.

  In a preferred embodiment, the Vickers hardness of the gasket placement portion 8 is desirably 20 HV points or more larger than the Vickers hardness of the filter placement portion 7. In a more preferred embodiment, it is still desirable that the Vickers hardness of the gasket placement portion 8 is 100 HV points or more greater than the Vickers hardness of the filter placement portion.

  In order to configure the Vickers hardness of the gasket arrangement portion 8 to be larger than the Vickers hardness of the filter arrangement portion 7, the gasket arrangement portion 8 can have a high Vickers hardness by being burnished, for example. Can do. In the burnishing process, a surface modification accompanied by a significant increase in Vickers hardness can be expected by applying a strong plastic stress to the metal surface layer to give a small plastic deformation. The burnishing process may be performed either before the filter 3 is welded to the base plate 2 or after the filter 3 is welded. In addition, as another aspect for configuring the Vickers hardness of the gasket placement portion 8 to be larger than the Vickers hardness of the filter placement portion 7, the gasket placement portion 8 may be shot peened.

  Although several embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments disclosed in the present specification, but the present invention described in the claims. All modifications, equivalents and modifications included in the idea are included.

  The gas filters (Examples and Comparative Examples) shown in FIGS. 1 to 4 were prototyped based on the specifications in Table 1, and the presence / absence of gas leakage and the appearance evaluation of the gasket arrangement portion were performed. About the Example, in order to comprise the Vickers hardness of a gasket arrangement | positioning part larger than the Vickers hardness of a filter arrangement | positioning part, the burnishing process was given to the gasket arrangement | positioning part. The evaluation method is as follows.

<Evaluation of gas leakage>
Each gas filter was attached to a leak detector with a screw tightened with a predetermined torque, and gas leakage on the first surface side and the second surface side of the base plate was measured. In Table 1, “None” is displayed when the amount of gas leakage is equal to or less than a predetermined reference value.

<Appearance of gasket placement area>
A gas filter was attached to the gas supply apparatus of the form shown in FIG. 5 with a screw tightened with a predetermined torque, and gas was filtered for a predetermined time. Thereafter, the gas filter was removed from the gas supply device, and the appearance of the gasket arrangement portion on the base plate was observed with the naked eye.
The results of the evaluation are shown in Table 1.

  As is clear from Table 1, none of the gas filters of the examples produced gas leakage, and the appearance of the gasket placement part after use had no problem. On the other hand, in the comparative example, although gas leakage did not occur, the indentation (plastic deformation part) that seems to have been pressed by the gasket has occurred in the gasket placement part after use, and it can be reused next time. It was impossible.

DESCRIPTION OF SYMBOLS 1 Gas filter 2 Base plate 2a Base plate 1st surface 2b Base plate 2nd surface 3 Filter 3a Filter base plate side edge 4 First through hole 5 Second through hole 7 Filter arrangement portion 8 Gasket arrangement portion 8A First gasket arrangement Part 8B Second gasket placement part 10 Gasket A First direction G Gas

Claims (11)

A gas filter,
A metal base plate having a first through hole through which gas can pass, and a filter joined to the base plate to clean the gas that has passed through the first through hole;
Around the first through hole of the base plate, a filter placement part for attaching the filter is formed so as to surround the first through hole, a filter placement part is formed so as to surround the filter placement part, and a gasket And a gasket arrangement part for attaching
The filter protrudes from the base plate in the first direction, and an end portion on the base plate side is welded to the filter arrangement portion,
The Vickers hardness of the gasket arrangement part is larger than the Vickers hardness of the filter arrangement part,
Gas filter.   The gas filter according to claim 1, wherein a second through hole different from the first through hole is formed in the base plate.   The gas filter according to claim 1, wherein the gasket arrangement portion includes a first gasket arrangement portion provided on a first surface that is a surface of the base plate in the first direction.   The gas filter according to claim 3, wherein the first gasket arrangement portion is continuous with the filter arrangement portion through a step.   The gas filter according to any one of claims 1 to 4, wherein the gasket arrangement portion includes a second gasket arrangement portion provided on a second surface that is a surface opposite to the first direction of the base plate. .   6. The gas filter according to claim 1, wherein in the cross section of the base plate, the filter placement portion has a tapered shape in which a thickness gradually decreases toward a center of the first through hole.   The gas filter according to any one of claims 1 to 6, wherein the gasket placement portion has a Vickers hardness of 170 HV or more.   The gas filter according to any one of claims 1 to 7, wherein a Vickers hardness of the gasket arrangement portion is 20 HV points or more larger than a Vickers hardness of the filter arrangement portion.   The gas filter according to any one of claims 1 to 8, wherein the filter is tapered toward the first direction.   The gas filter according to any one of claims 1 to 9, wherein the base plate has a thickness of 2.0 to 5.0 mm.   A gas supply device, wherein the gas filter according to any one of claims 1 to 10 is disposed in a flow path for supplying the gas.

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