WO2020217961A1 - Diaphragm, valve, and film forming method - Google Patents

Abstract

Provided is a technology capable of suppressing the retention of particles in a diaphragm. A diaphragm (30) includes a metal thin plate (31), and a thin film layer (32) formed on the entirety of a first surface (liquid contact surface (31A)) of the thin plate (31). The thin film layer (32) includes: an annular body portion (33); an annular inside portion (34) positioned radially inward with respect to the body portion; and an annular outside portion (35) positioned radially outward with respect to the body portion (33). The inside portion (34) includes an inside inclined face (34A) that approaches the first surface from an outer peripheral edge to an inner peripheral edge thereof. The outside portion (35) includes an outside inclined face (35A) that approaches the first surface from an inner peripheral edge to an outer peripheral edge thereof.

Description

Diaphragm, valve, and film formation method

The present disclosure relates to diaphragms, valves, and film forming methods used in semiconductor manufacturing equipment and the like.

With the miniaturization of semiconductors, it is required to suppress particles entering the process chamber. A diaphragm having a thin film layer formed on the substrate has been proposed in order to suppress the entry of particles into the process chamber.

Japanese Unexamined Patent Publication No. 2004-60741

Depending on the gas type, the thin film layer has weaker corrosion resistance than the diaphragm, and the thin film layer may peel off, leading to the generation of particles. Therefore, in order to reduce the amount of the thin film layer, it is desirable to form the thin film layer in an annular shape. However, if only the annular thin film layer is formed on the substrate, a particle retention portion is generated at the boundary between the thin film layer and the substrate.

Therefore, one of the purposes of the present disclosure is to provide a technique capable of suppressing the retention of particles in the diaphragm.

In order to solve the above object, the diaphragm according to one aspect of the present disclosure includes a thin metal plate and a thin film layer formed on one surface of the thin plate, and the thin film layer is an annular main body. A portion, an annular inner portion located inside the main body portion in the radial direction, and an annular outer portion located radially outside the main body portion are provided, and the inner portion is from the outer peripheral edge thereof. The outer peripheral portion has an inner inclined surface that approaches the one side surface as it approaches the inner peripheral edge, and the outer portion has an outer inclined surface that approaches the one side surface as it approaches the outer peripheral edge.

The boundary portion between the main body portion and the inner portion may have a convex shape, and the inner peripheral edge portion of the inner portion may have a concave shape.

A valve according to one aspect of the present disclosure includes a body in which a fluid passage is formed, a valve seat provided in the body, and the above-mentioned opening and closing of the fluid passage in contact with the valve seat and away from the valve seat. The thin film layer of the diaphragm is located on the valve seat side.

The film forming method according to one aspect of the present disclosure is a film forming method for forming a thin film layer on a thin plate using a first jig and a second jig, and the first jig has a circular opening in a plan view. A hole is formed, and an annular first inclined surface whose diameter increases as it approaches one side is formed at one end of the inner peripheral surface forming the opening hole, and the second jig has a columnar shape. The diameter of the opening hole is smaller than the inner diameter of the opening hole, and an annular second inclined surface 42B whose diameter decreases as it approaches the tip is formed at the tip of the outer peripheral surface thereof. The first jig is attached to the first jig so as to cover the first inclined surface, the second jig is inserted into the opening hole from the side opposite to the first inclined surface side, and the thin plate is used with the first jig. The thin film layer is formed on the annularly exposed portion between the second jig and the second jig.

According to the present disclosure, it is possible to provide a technique capable of suppressing the retention of particles in a diaphragm.

It is sectional drawing of the valve in an open state which concerns on embodiment. It is an enlarged cross-sectional view near the diaphragm in a valve in a closed state. (A) is a cross-sectional view of a thin plate and a thin film layer located closest to the sheet side, and (b) is an enlarged cross-sectional view of a part of the thin plate and the thin film layer of (a). It is explanatory drawing of the film formation method of forming a thin film layer on a thin plate. (A) is a bottom view of the first jig, and (b) is a partially enlarged sectional view of the first jig and the second jig. It is an enlarged sectional view of a part of the thin film layer which concerns on a modification. It is explanatory drawing of the 1st jig which concerns on a modification.

The diaphragm 30 and the valve 1 according to the embodiment of the present disclosure will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of the valve 1 in the open state according to the present embodiment.

As shown in FIG. 1, the valve 1 includes a body 10 and an actuator 20. In the following description, the actuator 20 side of the valve 1 will be referred to as the upper side, and the body 10 side will be referred to as the lower side.

[Body 10]
The body 10 includes a body body 11, a seat 12 which is a valve seat, a bonnet 13, a diaphragm 30, a holding adapter 14, a diaphragm holding 15, a holder 16, and a compression coil spring 17.

The body body 11 is formed with a valve chamber 11a and an inflow passage 11b and an outflow passage 11c communicating with the valve chamber 11a. The resin sheet 12 has an annular shape, and is provided on the peripheral edge of the body main body 11 where the valve chamber 11a and the inflow path 11b communicate with each other. As shown in FIG. 2, the top surface 12A of the sheet 12 has a flat shape. The inflow passage 11b and the outflow passage 11c correspond to fluid passages.

As shown in FIG. 1, the bonnet 13 has a substantially cylindrical shape with a lid, and is fixed to the body body 11 so as to cover the valve chamber 11a by screwing the lower end portion thereof into the body body 11.

The outer peripheral edge of the diaphragm 30, which is a valve body, is sandwiched and held by the pressing adapter 14 arranged at the lower end of the bonnet 13 and the bottom surface forming the valve chamber 11a of the body body 11. The fluid passage is opened and closed by separating and abutting (pressing) the diaphragm 30 with respect to the sheet 12. The detailed configuration of the diaphragm 30 will be described later.

The diaphragm retainer 15 is provided on the upper side of the diaphragm 30, and is configured to be able to press the central portion of the diaphragm 30. The diaphragm retainer 15 is fitted to the holder 16.

The holder 16 has a substantially cylindrical shape and is arranged in the bonnet 13 so as to be vertically movable. The stem 23B, which will be described later, is screwed to the upper part of the holder 16.

The compression coil spring 17 is provided in the bonnet 13 and always urges the holder 16 downward. The valve 1 is kept in a closed state by the compression coil spring 17 in a normal state (when the actuator 20 is not operating).

[Actuator 20]
The actuator 20 is an air-driven type and has a substantially cylindrical shape as a whole, and includes a casing 21, a partition disk 22, a first piston portion 23, and a second piston portion 24.

The casing 21 has a lower casing 21A and an upper casing 21B whose lower end is screwed to the upper end of the lower casing 21A. The lower casing 21A has a substantially stepped cylindrical shape. The outer circumference of the lower end of the lower casing 21A is screwed into the inner circumference of the through hole of the bonnet 13. The upper casing 21B has a substantially cylindrical shape with a lid. A fluid introduction path 21c is formed at the upper end of the upper casing 21B.

A nut 25 is screwed onto the outer circumference of the lower end of the lower casing 21A. The nut 25 comes into contact with the bonnet 13 and suppresses the rotation of the lower casing 21A with respect to the bonnet 13.

The partition disk 22 has a substantially disk shape and is immovably provided in the casing 21.

The first piston portion 23 has a first piston 23A, a stem 23B, and a first upper extension portion 23C. The first piston 23A is provided between the partition disk 22 and the lower casing 21A, and has a substantially disk shape. The first pressure chamber S1 is formed by the lower casing 21A and the first piston 23A.

The stem 23B extends downward from the central portion of the first piston 23A. The lower end of the stem 23B is screwed into the holder 16. The first upper extending portion 23C extends upward from the central portion of the first piston 23A and penetrates the partition disc 22.

A first fluid inflow path 23d extending in the vertical direction and communicating with the first pressure chamber S1 and the second pressure chamber S2 is formed in the first piston 23A, the stem 23B, and the first upper extending portion 23C.

The second piston portion 24 has a second piston 24A and a second upper extension portion 24B. The second piston 24A is provided between the partition disk 22 and the upper casing 21B, and has a substantially disk shape. A second pressure chamber S2 is formed by the partition disc 22 and the second piston 24A. The upper end portion of the first upper extension portion 23C is connected to the second piston 24A.

The second upper extension portion 24B extends upward from the central portion of the second piston 24A and is inserted into the fluid introduction path 21c. A second fluid inflow passage 24c communicating with the fluid introduction passage 21c and the first fluid inflow passage 23d is formed in the second upper extension portion 24B.

[Opening and closing operation of valve 1]
Next, the opening / closing operation of the valve 1 according to the present embodiment will be described.
FIG. 2 is an enlarged cross-sectional view of the valve 1 in the closed state in the vicinity of the diaphragm 30.

In the valve 1 of the present embodiment, when the driving fluid does not flow into the first and second pressure chambers S1 and S2, the holder 16 and the stem 23B are lowered by the urging force of the compression coil spring 17 as shown in FIG. At the dead point (close to the body body 11), the diaphragm 30 is pushed by the diaphragm retainer 15, the lower surface of the diaphragm 30 is pressed against the seat 12, and the valve 1 is closed. That is, the valve 1 is in a closed state in a normal state (a state in which the driving fluid is not supplied).

Then, the drive fluid is made to flow from the drive fluid supply source (not shown) to the valve 1. As a result, the driving fluid is supplied to the valve 1. The drive fluid passes through the fluid introduction passage 21c, the first and second fluid inflow passages 23d and 24c, and flows into the first and second pressure chambers S1 and S2 via an air tube and a pipe joint (not shown). To do. When the driving fluid flows into the first and second pressure chambers S1 and S2, the first and second pistons 23A and 24A rise against the urging force of the compression coil spring 17. As a result, the holder 16, the diaphragm retainer 15, and the stem 23B move to the top dead point and separate from the body body 11, and the diaphragm 30 moves upward due to the elastic force and the pressure of the fluid (gas), and flows out from the inflow path 11b. The valve 1 is in an open state when it communicates with the road 11c.

To change the valve 1 from the open state to the closed state, the three-way valve (not shown) is switched to a flow in which the driving fluid is discharged from the actuator 20 (first and second pressure chambers S1 and S2) of the valve 1 to the outside. As a result, the driving fluid in the first and second pressure chambers S1 and S2 is discharged to the outside through the first and second fluid inflow passages 23d and 24c and the fluid introduction passage 21c. As a result, the holder 16 and the stem 23B move to the bottom dead center by the urging force of the compression coil spring 17, and the valve 1 is closed.

[Diaphragm 30]
Next, the configuration of the diaphragm 30 will be described.

The diaphragm 30 has a spherical shell shape, and the upwardly convex arc shape is in a natural state. The diaphragm 30 includes, for example, a plurality of thin metal plates 31 and a thin film layer 32. Each thin plate 31 is made of nickel-cobalt alloy, stainless steel, or the like, and is formed in a spherical shell shape by cutting out a flat plate-shaped material in a circular shape and bulging the central portion upward.

FIG. 3A is a cross-sectional view of the thin plate 31 and the thin film layer 32 located closest to the sheet 12, and FIG. 3B is an enlarged cross-sectional view of a part of the thin plate 31 and the thin film layer 32 of (a). is there.

The thin film layer 32 is formed in an annular shape on the wetted surface 31A, which is the concave surface of the thin plate 31. The wetted surface 31A corresponds to one surface of the thin plate 31. The thin film layer 32 is, for example, a carbon film or a fluororesin film. The carbon film is, for example, a DLC (Diamond-like Carbon) film, and the fluororesin film is, for example, tetrafluoroethylene resin (PTFE), tetrafluoroethylene hexafluoropropylene copolymer (FEP), or tetrafluoroethylene. -Perfluoroalkyl vinyl ether copolymer (PFA). The film thickness of the thin film layer 32 is, for example, 2 to 4 μm. Therefore, it is possible to provide the diaphragm 30 having excellent low friction, wear resistance, and corrosion resistance, and it is possible to suppress the transfer of the sheet 12 to the diaphragm 30 contact portion.

The thin film layer 32 includes an annular main body 33, an annular inner portion 34 located radially inside the main body 33, and an annular outer portion 35 located radially outward with respect to the main body 33. Be prepared. The film thickness of the main body 33 is, for example, 2 to 4 μm. The main body 33 has a substantially rectangular cross section along the radial direction, and the lower surface 33A is substantially parallel to the wetted surface 31A. The radial width of the lower surface 33A is larger than the radial width of the top surface 12A of the sheet 12. The inner portion 34 has an inner inclined surface 34A that approaches the wetted surface 31A as it approaches the inner peripheral edge from the outer peripheral edge thereof. The outer portion 35 has an outer inclined surface 35A that approaches the wetted surface 31A as it approaches the outer peripheral edge from the inner peripheral edge thereof.

Next, the manufacturing method of the diaphragm 30 will be described.

FIG. 4 is an explanatory diagram of a film forming method for forming a thin film layer 32 on a plurality of thin plates 31. In FIG. 4, only one thin plate 31 is shown.
FIG. 5A is a bottom view of the first jig 41, and FIG. 5B is a partially enlarged cross-sectional view of the first jig 41 and the second jig 42.

First, prepare multiple disc-shaped and flat-plate-shaped thin plates (materials), stack them, and bond them together with an adhesive or the like to integrate them. A plurality of integrated thin plates 31 are fixed to a jig of a pressing device, and a central portion is pressed by a punch to form a spherical shell.

Next, the plurality of thin plates 31 after molding are fixed to the first metal or resin jig 41 of the film forming apparatus 40.

As shown in FIGS. 4A and 5A, the first jig 41 has a substantially square plate shape in a plan view, and a circular opening hole 41a in a plan view is formed in the central portion on the lower surface side thereof. ing. The first jig 41 is formed with a slit 41b extending from one side surface (upper side surface in FIG. 5A) toward the other side surface (lower side surface in FIG. 5A). The slit 41b opens on one end surface and communicates with the opening hole 41a. The slit 41b has a substantially spherical shell shape that is convex upward at the central portion of the first jig 41. As shown in FIG. 5B, in the first jig 41, the end portion of the inner peripheral surface 41C forming the opening hole 41a on the slit 41b side has an annular diameter that increases as it approaches the slit 41b side (outside). The first inclined surface 41D of the above is formed.

The thin plate 31 is inserted through the opening on the side surface of the first jig 41, and the thin plate 31 is attached to the first jig 41 as shown in FIG. 4A. As a result, the thin plate 31 is attached to the first jig 41 so as to cover the first inclined surface 41D, and the wetted surface 31A of the thin plate 31 is exposed to the outside through the opening hole 41a.

Next, the second jig 42 is inserted into the opening hole 41a and brought into contact with the wetted surface 31A of the thin plate 31. The second jig 42 is made of metal or resin and has a columnar shape. The diameter of the second jig 42 is smaller than the inner diameter of the opening hole 41a. The second jig 42 is inserted into the opening hole 41a so that the central axis of the opening hole 41a and the central axis of the second jig 42 are coaxial with each other. Of the wetted surface 31A of the thin plate 31, the portion exposed through the opening hole 41a has an annular shape. As shown in FIG. 5B, an annular second inclined surface 42B whose diameter decreases as it approaches the tip is formed at the tip of the outer peripheral surface 42A of the second jig 42.

Next, as shown in FIG. 4 (c), the thin film layer 32 is formed on the annularly exposed portion of the wetted surface 31A of the thin plate 31. When the thin film layer 32 is a DLC film, the thin film layer 32 is formed by a physical vapor deposition method (PVD) and / or a chemical vapor deposition method (CVD). For example, a DLC film is formed by combining magnetron sputtering and PACVD (plasma assist CVD). When the thin film layer 32 is a PFA film, an electrostatic coating is used to form a film. When the thin film layer 32 is a DLC film, spray coating may be used.

Then, by removing the first jig 41 and the second jig 42, the diaphragm 30 can be obtained. That is, a diaphragm 30 is obtained in which a thin film layer 32 having an inner inclined surface 34A of the inner portion 34 and an outer inclined surface 35A of the outer portion 35 is formed along the first inclined surface 41D and the second inclined surface 42B.

According to the valve 1 provided with the diaphragm 30 of the present embodiment described above, the thin film layer 32 has an annular main body 33, an annular inner portion 34 located radially inside the main body 33, and a main body. An annular outer portion 35 located on the outer side in the radial direction with respect to 33 is provided, and the inner portion 34 has an inner inclined surface 34A that approaches the liquid contact surface 31A as it approaches the inner peripheral edge from the outer peripheral edge thereof, and the outer portion 35. Has an outer inclined surface 35A that approaches the wetted surface 31A as it approaches the outer peripheral edge from the inner peripheral edge thereof. According to this configuration, it is possible to prevent particles from staying at the boundary between the thin film layer 32 and the thin plate 31 of the diaphragm 30 during purging. Therefore, it is possible to suppress the entry of particles staying in the process chamber during the manufacture of the semiconductor, and it is possible to improve the yield of the semiconductor.

According to the film formation of the thin film layer 32 on the thin plate 31 using the first jig 41 and the second jig 42 of the present embodiment, the first jig 41 is formed with an opening hole 41a having a circular shape in a plan view. At one end of the inner peripheral surface forming the hole 41a, an annular first inclined surface 41D whose diameter increases as it approaches one side is formed, and the second jig 42 has a columnar shape and its diameter. Is smaller than the inner diameter of the opening hole 41a, and an annular second inclined surface 42B whose diameter decreases as it approaches the tip is formed at the tip of the outer peripheral surface thereof. Then, the thin plate 31 is attached to the first jig 41 so as to cover the first inclined surface 41D, and the second jig 42 is inserted into the opening hole 41a from the side opposite to the first inclined surface 41D side to form the thin plate 31. A thin film layer 32 is formed on the annularly exposed portion between the first jig 41 and the second jig 42.

As a result, the inner portion 34 has an inner inclined surface 34A that approaches the liquid contact surface 31A as it approaches the inner peripheral edge from the outer peripheral edge thereof, and the outer portion 35 has a liquid contact surface 31A as it approaches the outer peripheral edge from the inner peripheral edge thereof. The thin film layer 32 having the approaching outer inclined surface 35A can be formed. Therefore, it is possible to prevent particles from staying at the boundary between the thin film layer 32 and the thin plate 31 of the diaphragm 30 during purging.

Note that the present disclosure is not limited to the above-described embodiment. A person skilled in the art can make various additions and changes within the scope of the present disclosure.

The number of thin plates 31 was a plurality, but it may be one. Further, although the top surface 12A of the sheet 12 is flat, it may be an upwardly convex curved surface (the cross-sectional shape along the radial direction is an R surface). The actuator 20 was an air-driven type, but may be an electromagnetically driven type or a piezo element driven type.

As shown in FIG. 6, the boundary portion 34B between the main body portion 33 and the inner portion 34 may have a convex shape, and the inner peripheral edge portion 34C of the inner portion 34 may have a concave shape. Similarly, the boundary portion 35B between the main body portion 33 and the outer portion 35 may have a convex shape, and the outer peripheral edge portion 35C of the inner portion 35 may have a concave shape. According to this configuration, it is possible to further suppress the retention of particles at the boundary between the thin film layer 32 and the thin plate 31 during purging.

As shown in FIG. 7, the first jig 41 may be composed of the 1-1 jig 41E and the 1-2 jig 41F. An opening hole 41a and a first inclined surface 41D are formed in the 1-1 jig 41E, and a slit 41b is formed by combining the 1-1 jig 41E and the 1-2 jig 41F.

1: Valve 11: Body body 11b: Inflow path 11c: Outflow path 12: Seat 30: Diaphragm 31: Thin plate 31A: Wet contact surface 32: Thin film layer 33: Main body 34: Inner part 34A: Inner inclined surface 35: Outer part 35A: Outer inclined surface 41: First jig 41a: Opening hole 41C: Inner peripheral surface 41D: First inclined surface 41E: 1-1 jig 41F: 1-2 jig 42: Second jig 42A: Outer peripheral surface 42B: Second slope

Claims (5)

1. With a thin metal plate
   A diaphragm comprising a thin film layer formed in an annular shape on one surface of the thin plate.
2. The thin film layer includes an annular main body portion, an annular inner portion located inside the main body portion in the radial direction, and an annular outer portion located radially outside the main body portion.
   The inner portion has an inner inclined surface that approaches the one side surface as it approaches the inner peripheral edge from the outer peripheral edge thereof.
   The diaphragm according to claim 1, wherein the outer portion has an outer inclined surface that approaches the one side surface as it approaches the outer peripheral edge.
3. The boundary between the main body and the inner side has a convex shape.
   The diaphragm according to claim 2, wherein the inner peripheral edge portion of the inner portion has a concave shape.
4. The body with the fluid passage and
   The valve seat provided on the body and
   The diaphragm according to any one of claims 1 to 3, which abuts on the valve seat and opens and closes the fluid passage away from the valve seat.
   The thin film layer of the diaphragm is a valve located on the valve seat side.
5. A film forming method for forming a thin film layer on a thin plate using a first jig and a second jig.
   A circular opening hole is formed in the first jig in a plan view, and an annular first inclined surface whose diameter increases as it approaches one side at one end of the inner peripheral surface forming the opening hole. Is formed,
   The second jig has a columnar shape, the diameter of which is smaller than the inner diameter of the opening hole, and an annular second inclined surface whose diameter decreases as it approaches the tip is formed at the tip of the outer peripheral surface thereof. Being done
   The thin plate is attached to the first jig so as to cover the first inclined surface.
   The second jig is inserted into the opening hole from the side opposite to the first inclined surface side.
   A film forming method for forming a thin film layer on a portion of the thin plate that is cyclically exposed between the first jig and the second jig.
   
   

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