JPH06346980A - Bellows valve - Google Patents

Abstract

PURPOSE:To improve productivity through improvement of the substitution characteristics of raw material gas by a method wherein a hollow part is separated keeping gas tightness into a bellows presence area and an aperture presence area through the annular fixing tool of a bellows complete body or a rod. CONSTITUTION:A coupling member 12 in which a fixing ring 136 is incorporated and a drive part housing 111 are securely screw-locked in a state that a coil spring and a piston are inserted. A rod 114 fixed to a flow passage opening closing block 113 is inserted in a bellows complete body 232 at the annular fixing tool part from a position below a coupling member and fixed to a piston. Further, a cover is fixed to a drive housing 111 and a feed part housing 231 is fixed to a fixing ring 136 to form a given bellows valve 2. In the bellows valve 2, since a portion between a flow passage 131c in a feed part housing 231 and a hollow part 131d is partitioned by a partition wall 231a containing a ring packing 231c, even when raw material gas is fed, contact of gas with a bellows region is excellent and reliable gas molecule substitution is practicable in a short time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing these fluids connected to a piping system of an apparatus for utilizing a fluid such as a raw material gas in a vapor phase growth apparatus or a plating solution in a plating apparatus in a semiconductor device manufacturing process. The present invention relates to the structure of a bellows valve that turns ON / OFF the supply to the bellows valve, and particularly to a bellows valve that improves the productivity of a manufacturing device by improving the displacement characteristics of these fluids.

In the field of semiconductor devices in recent years, there is a strong demand for eliminating foreign substances from adhering during the manufacturing process as the degree of integration increases. In a bellows valve for supplying a raw material gas used in a vapor phase growth apparatus for contacting with each other to form crystals and the like on the surface, there are cases in which a plurality of kinds of raw material gas are controlled, and therefore foreign matter on the wafer surface How to realize the removal of the residual components inside the valve in order to eliminate the adherence in a short time, in other words, how to improve the replacement characteristic of the raw material gas has become a major issue.

[0003]

2. Description of the Related Art A case where a fluid is a source gas will be described below as an example. Fig. 4, which is a side view in a cross section passing through the central axis, is a diagram schematically illustrating an example of a conventional bellows valve configuration, and (4-1) shows a state when the supply of the raw material gas is cut off. -2) shows the state when the gas is supplied.

That is, when the bellows valve 1 is roughly classified in FIG. 4, the bellows valve 1 is circular in a plan view in the axial direction and has an air supply port on its side wall.
A drive unit 11 formed by projecting 111a, and a pipe-shaped connecting member screwed and fixed to the drive unit 11 in the axial direction thereof.
The raw material gas supply unit 13 is fixed to the drive unit 11 via 12 and has a circular shape in plan view in the axial direction.

The inner drive unit 11 is provided with the air supply port 11 described above.
A drive unit housing 111 including 1a, and a cylinder portion formed to communicate with the supply port 111a in the inner axial direction thereof.
111b, which can move axially with airtightness at 111b,
And a cover 116 that covers the cylinder portion 111b with its opening.

In the axial direction of one side of the piston 112, a pipe-shaped projecting portion 11 having a flange 112a that expands outward at the tip end is formed.
2b is formed, and a rod 114 is fixed on the central axis thereof with a passage opening / closing piece 113 having a tapered conical surface 113a at its tip with a length reaching a predetermined position in the fluid supply section 13 described above. Are arranged so as to penetrate the protrusion 112b.

On the other hand, a female screw formed following the cylinder portion 111b of the housing 111 which constitutes the drive portion 11
At the end of the connecting member 12 which is screwed and fixed to the housing 111 in the region of 111c, a flange extending inward is provided at the end of the connecting member 12 on the drive unit side.
12a is formed, and the collar 12a and the piston 11 described above are formed.
The coil spring 115 is inserted between the flange 112a formed at the end of the second protrusion.

When, for example, compressed air is injected from the air supply port 111a, the above-mentioned piston 112 can be lifted up against the coil spring 115 by its pressure. Spring
The restoring force of 115 causes the piston 112 to descend.

This means that the compressed air from the air supply port 111a is injected or released to release the piston 112.
This means that the flow path opening / closing piece 113 integrated with the above can be moved up and down.

On the other hand, a raw material gas supply port 13 provided with a raw material gas injection port 131a connected to a raw material gas tank (not shown) and a raw material gas discharge port 131b connected to a vapor phase growth apparatus (not shown) in a substantially diametrical direction is provided outside Is provided with each of the ports 131a and 131b, and the inside thereof has a flow passage 131c which communicates between the ports and the flow passage on the central axis with respect to the outer diameter.
A supply portion housing 131 in which a hollow portion 131d connected to 131c is formed, and the other end surface via a bellows when one end surface is brought into contact with the lower end surface of the connecting member 12 is a conical base of the flow path opening / closing piece 113. Finished bellows 132 mounted on a surface,
And a fixing ring 136 that integrates the connecting member 12 and the supply portion housing 131 in their respective outer diameter regions.

Since the communication area between the flow path 131c and the hollow portion 131d is formed in the conical opening hole 131e which fits the conical surface 113a of the flow path opening / closing piece 113, the opening hole 131e is formed. By bringing the conical surface 113a of the flow path opening / closing piece 113 into contact with the flow path opening / closing piece 113, the flow path 131c connecting the raw material gas injection port 131a and the raw material gas discharge port 131b can be blocked as shown in the drawing.

The completed bellows 132 is a ring-shaped fitting 133 having a flange 133a sandwiched between the lower end surface of the connecting member 12 and the upper end surface of the supply portion housing 131, and the conical base surface of the flow path opening / closing piece 113. Ring-shaped fixture fixed to
A bellows 135 is fixed between the bellows 135 and 134 by means such as welding.

The hollow portion 13 of the supply portion housing 131
1d is formed in such a size that the bellows 135 can be accommodated with a sufficient margin. Therefore, after fixing the coupling member 12 and the drive unit housing 111 in which the fixing ring 136 is incorporated with the coil spring 115 and the piston 112 by screwing and fixing, the completed bellows 132 is the ring-shaped fixing member.
The rod 114 fixed to the flow path opening / closing piece 113 on the 134 side is inserted from below the connecting member to be integrated with the piston 112, and further the cover 116 is fixed to the drive unit housing 111 and the supply unit housing 131 and the above fixing. By integrating with the ring 136, the bellows valve 1 can be constructed as shown in (4-1).

In this state, the piston 112 moves the coil spring 11
Since it is pressed downward by 5, the piston 112
Flow path opening / closing piece 11 located at the tip of rod 114 integrated with
3 is fitted in the above-mentioned opening hole 131e of the supply unit housing 131, and as a result, the raw material gas A injected from the injection port 131a is blocked by the flow path opening / closing piece 113.

However, the compressed air B is supplied from the air supply port 111a.
Is injected, the piston 112, that is, the flow path opening / closing piece 113, rises due to the pressure (the amount of rise in this case is the bellows 13
5), so that the flow path 131c of the raw material gas A is formed as shown in (4-2) and the raw material gas A can be supplied from the raw material gas discharge port 131b to a vapor phase growth apparatus (not shown). it can.

When the compressed air B is released, the coil spring 115 causes the piston 112 to descend.
Returning to the same state as 1), the discharge port 131b for the source gas A
Outflow is blocked.

In the bellows valve 1 having such a structure, compressed air is supplied to the air supply port 111a or is released to supply the source gas A to the vapor phase growth apparatus.
N-OFF can be realized.

When the raw material gas A is switched to another raw material gas, the injection of the compressed air B is canceled and once (4
After returning to the state of -1), the source gas A in the flow path 131c is replaced with another source gas by injecting another source gas from the source gas injection port 131a in the state of (4-2). You can

[0019]

However, in the bellows valve 1 having the conventional structure, the raw material gas is brought into contact with the entire circumference of the surface of the bellows 135 in the state of supplying the raw material gas, that is, in the state of (4-2) in FIG. Therefore, the gas molecules are easily attached to each surface, and when the source gas is switched to another source gas, the residual molecules of the previous source gas are discharged from the source gas discharge port 131b together with the other source gas, In the vapor phase growth apparatus connected to it, it acts as a foreign substance.

Therefore, the gas replacement time is extended so that the raw material gas molecules attached to the surface of the bellows are surely replaced with the new raw material gas molecules and then fed into the vapor phase growth apparatus. However, it is difficult to surely replace the gas molecules because the surface area is large and the replacement property of the gas molecules is deteriorated as a result, which may hinder the high integration of the semiconductor device. .

[0021]

SUMMARY OF THE INVENTION The above-mentioned problems include a drive unit, a fluid supply unit, and a connecting member that engages both of them.
A bellows valve which is connected in the middle of a fluid piping system at the fluid supply unit and intermittently or switches the required fluid to a manufacturing apparatus connected to the piping system, the supply constituting the fluid supply unit Mounted on the tip of a rod that can reciprocate in the axial direction by an external force from the drive unit while expanding and contracting the bellows region of the completed bellows in a state where the periphery is sealed by the completed bellows located in the hollow part of the housing. The opened / closed flow path opening / closing piece is brought into contact with or separated from an opening hole provided at a position corresponding to the rod of the flow path in the supply unit housing so that the flow path can be blocked by the contact of the flow path opening / closing piece. In the meantime, the supply housing of the bellows valve, which supplies the required fluid intermittently or in a switching manner, is provided in its hollow portion through the ring-shaped fixing member of the finished bellows or the rod. Part of being resolved by a bellows valve that is configured to include a partition wall that can separate hermetically the bellows existent region and the opening hole existent region.

[0022]

When the bellows valve is constructed so that the contact area with the raw material gas inside becomes small, the substitution characteristic of the raw material gas can be improved.

Therefore, in the present invention, the valve is constructed by isolating the bellows region having a large surface area due to the unevenness from the raw material gas passage. Therefore, the contact area with the raw material gas inside the valve can be limited to only the gas flow path, and the improvement of the raw material gas replacement characteristic as the valve can be realized, which eventually leads to the manufacturing equipment (in this figure, vapor phase growth). It can be expected to improve productivity as a device.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a view for explaining the operation of a bellows valve according to the present invention, in which the main parts of the bellows valve according to the present invention have been extracted. Similarly to FIG. (1-2) shows the state when the gas was supplied.

FIG. 2 is a diagram showing another configuration example, and FIG. 3 is a diagram for explaining the effect of the bellows valve of the present invention. Note that, in each of the drawings, the case where the bellows valve described in FIG. 4 is applied is taken as an example, and thus the same target members and parts as those in FIG. 4 are designated by the same reference numerals and duplicate description will be omitted. Omit it.

That is, in FIG. 1, the bellows valve 2 is the supply portion housing 13 of the bellows valve 1 described in FIG.
Only the 1 and the completed bellows 132 are replaced with the supply housing 231 and the completed bellows 232 that realize the present invention.

In particular, the supply housing 231 in this case is
A partition wall 231a protruding inward is additionally formed at an axial center of the supply unit housing 131 shown in FIG. 4, and the inner surface 231b has an inner diameter surface 231b.
A ring packing 231c is provided so as to keep sliding airtightness with respect to the outer diameter portion of the second ring-shaped fixture 134.

The partition wall 231a is formed, for example, in an extracted view (a).
As shown in FIG. 7, a plate-shaped partition plate 231a 'separately formed in the axial intermediate region of the supply unit housing 131 can be easily formed by sandwiching it while keeping airtightness.

The completed bellows 232 corresponds to only the ring-shaped fixing member 134 of the completed bellows 132 described in FIG. 4 with the ring packing 231c of the housing 231 over the entire movement range of the piston 112 and the fixing member 134. It is a ring-shaped fixing device 234 having a length to be obtained.

This means that, within the range of movement of the ring-shaped fixture 234 that moves together with the piston 112, the partition wall 23 is always present.
It is shown that 1a can make contact with the ring-shaped fixing member 234 in an airtight state.

Therefore, as described with reference to FIG. 4, the fixing ring 13
After the connecting member 12 in which 6 is incorporated and the drive unit housing 111 are screwed and fixed with the coil spring 115 and the piston 112 (not shown) being inserted, the completed bellows 232 forms the flow path at its ring-shaped fixture portion. A rod 114 fixed to the opening / closing piece 113 is inserted from below the connecting member to be fixed to the piston 112, and a cover 116 (not shown) is fixed to the drive unit housing 111 and the supply unit housing 231 is fixed to the fixing ring 136. Then, the required bellows valve 2 can be configured as shown in (1-1).

In this state, as in FIG. 4, the piston 112, and thus the flow path opening / closing piece 113, is pressed downward by the coil spring 115 and is fitted into the opening hole 131e of the supply portion housing 231, so that the raw material gas is eventually discharged. The raw material gas A injected from the injection port 131a is blocked by the passage opening / closing piece 113.

However, the air supply port 11 described with reference to FIG.
When compressed air is injected from 1a, the pressure causes the piston 112, in other words, the passage opening / closing piece 113 to rise, so that the passage 131c for the raw material gas A is between the injection port 131a and the discharge port 131b as shown in (1-2). When the raw material gas A is formed, the exhaust port 131b
Can be supplied to a vapor phase growth apparatus (not shown).

As in the case of FIG. 4, the injection of compressed air is canceled to return to the same state as (1-1) and the raw material gas A is shut off. In the bellows valve 2 having such a configuration, the flow passage 131c and the hollow portion 131d in the supply unit housing 231 are separated by the partition wall 231a including the ring packing 231c, so that the gas is supplied to the bellows region even when the source gas is supplied. Since there is no contact, it is possible to surely perform the gas molecule replacement in a short time gas replacement work, and it is possible to improve the productivity by improving the gas molecule replacement characteristics.

FIG. 2 shows the supply housing 23 described with reference to FIG.
This is an example of a case where the separation of the hollow portion 131d by one partition wall 231a is realized by a rod. That is, in FIG. 2, the bellows valve 3 includes only the supply portion housing 231 and the completed bellows body 232 of the bellows valve 2 described in FIG.
It is replaced with a different supply housing 331 and a finished bellows body 332.

And in this case, the supply unit housing 331
The height of the partition wall 331a is increased so that the sliding airtightness can be maintained with respect to the rod surface. A ring packing 331c similar to that shown in FIG. 1 is arranged on the inner diameter surface 331b.

The completed bellows 332 is, for example, one in which the ring-shaped fixture 234 of the completed bellows 232 described in FIG. 1 is replaced with a thin ring-shaped fixture 334 and a part of the rod 114 is exposed. In the figure, the ring-shaped fixture 334 having substantially the same thickness as the ring-shaped fixture 134 described in FIG. 4 is fixed to the lower end surface of the bellows of FIG. 1 as shown.

In the bellows valve 3 as described above, the flow passage 131c and the hollow portion 331d in the supply portion housing 331 are separated by the partition wall 331a including the ring packing 331c, so that the same effect as in FIG. 1 can be obtained.

FIG. 3 exemplifying the experimental results of the substitution characteristics between oxygen gas and nitrogen gas, where the horizontal axis X is the nitrogen gas injection time T (sec) and the vertical axis Y is the residual oxygen concentration H (ppm). The broken line shows the gas displacement characteristic of the bellows valve 1 described in FIG. 4, and is the bellows valve described in FIG.
3 shows a gas replacement characteristic of the valve 2.

For example, comparing the residual oxygen gas concentrations at 30 seconds and 50 seconds after nitrogen gas injection between the conventional bellows valve 1 and the bellows valve 2 according to the present invention, the residual oxygen gas concentration in the former case is compared. Is about 4.6ppm, 3.0p
It was confirmed that the latter was about 2.2 ppm and 1.2 ppm, while the residual concentration was less than 1/2 of the former, which was more than twice that of the former.

[0041]

As described above, according to the present invention, it is possible to provide a bellows valve which improves the replacement characteristic of the raw material gas and improves the productivity.

In the description of the present invention, the case where the fluid is a gas as a source gas is taken as an example, but it is clear that the same effect can be obtained even when the fluid is a liquid. It is also apparent that in the manufacturing apparatus in which the bellows valve according to the present invention is arranged in the piping system, the same effect can be obtained as the manufacturing apparatus by operating the bellows valve according to the procedure described above.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the operation of a bellows valve according to the present invention.

FIG. 2 is a diagram showing another configuration example.

FIG. 3 is a diagram for explaining the effect of the bellows valve of the present invention.

FIG. 4 is a diagram schematically illustrating a conventional bellows valve configuration example.

[Explanation of symbols]

2, 3 Bellows valve 12 Connecting member 113 Flow path opening / closing piece 114 Rod 131a Fluid injection port (raw material gas injection port) 131b Fluid discharge port (raw material gas discharge port) 131c Flow path 131d Hollow part 131d Hollow part 131e Open hole 136 Fixed Ring 231,331 Supply housing 231a, 331a Partition wall 231a 'Partition plate 231b, 331b Inner diameter surface 231c, 331c Ring packing 232,332 Complete bellows 234,334 Ring-shaped fixture

Claims (1)

[Claims] 1. A drive unit, a fluid supply unit, and a connecting member that engages both of them, and a fluid required for a manufacturing apparatus connected to the pipe system of the fluid at the fluid supply unit and connected to the pipe system. A bellows valve for intermittently or switchingly supplying a fluid, the periphery of which is sealed by a completed bellows (232) located in a hollow portion (131d) in a supply housing (231) that constitutes the fluid supply section. While expanding and contracting the bellows region of the completed bellows body (232) in this state, a flow path opening / closing piece (113) mounted at the tip of a rod (114) capable of reciprocating in the axial direction by an external force from the driving unit is provided. The opening (131e) is provided at the position corresponding to the rod (114) of the flow path (131c) in the housing of the supply unit so that the flow path can be blocked by the contact of the flow path opening / closing piece (113). The contact or separation is performed to supply the required fluid intermittently or in a switched manner. The supply part housing (231) of the rise valve has a hollow part (131d) in which the hollow part (231) of the completed bellows (232) is inserted through the ring-shaped fixture (234) or the rod (114). A bellows valve comprising a partition wall (231a) capable of separating 131d) into a bellows existence region and an opening hole existence region while keeping airtightness.