JP2705285B2 - Integrated valve structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] The present invention relates to a gas flow path of a vapor phase growth apparatus used for manufacturing a semiconductor device and the like, and aims at simplifying a flow path structure including a plurality of valves and reducing a chance of contamination. A first gas flow path connecting the raw material gas inlet to the first valve, a second gas flow path connecting the first valve to the gas outlet, and a branch from the first gas flow path. A gas flow path connected to the second valve, a gas flow path connected to the third valve and coupled to the second gas flow path, a connection port between the second valve and the first raw material container. Third to connect
A gas flow path branched from the third gas flow path and connected to the fourth valve; and a fourth gas path connecting the second raw material container connection port and the fourth valve.
And a gas flow path branched from the fourth gas flow path and connected to the fifth valve, and the first to fifth five valves are one Valve support
It is configured with a structure fixed to 30.

The role of these valves is that the first valve opens and closes a path directly connecting the carrier gas piping system and the reaction chamber piping system, and the second and third valves respectively serve as the raw material container and the carrier gas piping system. The fourth and fifth valves open and close a path connecting the reaction chamber piping system, and open and close the connection between these two raw material container connection paths and the vacuum exhaust device.

[Industrial applications]

The present invention relates to a gas flow path configuration of a vapor phase growth apparatus used for manufacturing a semiconductor device and the like, and particularly to a flow path switching mechanism using a valve.

In the manufacture of a semiconductor device, processing steps of vapor phase growth such as epitaxial growth of a semiconductor crystal and deposition formation of a polycrystalline or amorphous semiconductor material and an insulating material are indispensable. The vapor phase growth apparatus includes a piping system for transporting a source gas to the reaction chamber or discharging the source gas from the reaction chamber. In addition to use, it is necessary to suppress contamination in the reaction chamber and piping system.

In particular, the piping system has a large area in contact with a raw material or a carrier gas (hereinafter, these are collectively referred to as a raw material gas), and is likely to be contaminated by emission of impurities from the pipe wall. To avoid such inconveniences, it is necessary to shorten the piping route and reduce the chance of contamination.However, in order to supply the raw material gas at an appropriate speed, the piping system must be complicated to some extent. It is.

[Problems to be solved by conventional technology and invention]

When the source material for vapor phase growth is a liquid under normal use conditions, the simplest piping configuration for carrying the material out of the container by bubbling a carrier gas and transporting it to the reaction chamber is as shown in FIG. It will be. In the figure, 10 is a carrier gas container, 11, 16, 17 are valves, and 20 is a raw material container.
Is a reaction chamber.

The valve 11 is for sending the carrier gas directly to the reaction chamber, and if this valve is closed and the valves 12 and 13 are opened,
The raw material vaporized by bubbling is transported from the raw material container to the reaction chamber. The reaction chamber is often kept under reduced pressure and is not shown in the figure. In this case, however, the exhaust port of the reaction chamber is connected to a vacuum pump via a valve for adjusting the pressure.

Considering the case where such a configuration is applied to an actual device, the valves 16 and 17 are necessary to seal the raw material container when not connected. It will be provided between the system side.

However, in this valve configuration, since the piping system is released to the atmosphere when the container is removed, it is necessary to add valves 12 and 13 as shown in FIG. 5 to avoid this. The joint 22 is connected to the valve 12 as viewed from the piping system as shown.
And 13 are provided outside.

In such a piping system, if the valve portions are to be integrated and integrated, the three components 12, 13, and 14 can be integrated into one. Actually, when a piping system in which these valves are integrated is used, an effect of reducing contamination of the source gas is recognized.

On the other hand, apart from such a decrease in the surface area inside the tube, there is a case where it is necessary to prevent the raw material from being released into the atmosphere. This corresponds to the case where the raw material is extremely active like an alkyl metal, and has a function to exhaust and remove the inside so that the raw material gas does not remain in the piping part that is released to the atmosphere when the container is replaced. It becomes necessary. Such a structure also has a function of quickly removing gas that has entered the tube when the container is replaced, and is indispensable for a vapor phase growth apparatus.

The valves corresponding to the valves 11, 12, and 13 in Fig. 5 are integrated together, and the piping system to which valves 16 and 17 for opening and closing the connection port to the exhaust device are added, and only the valve connection portion is taken out. FIG. A portion 31 enclosed by a broken line including three valves 11, 12, and 13 is integrated and attached together in a box.

Although the effect of integration can be recognized in the configuration shown in FIG. 3, the complexity of the piping with the increase in the number of valves increases the possibility of contamination of the source gas, and the increase in the number of joints increases the possibility of leakage. It will increase.

An object of the present invention is to provide a piping system structure in which the occurrence of contamination and leaks is sufficiently suppressed even in a configuration in which a valve is additionally provided for discharging residual gas from the piping system.

[Means for solving the problem]

In order to achieve the above object, an integrated valve structure according to the present invention comprises: a first gas passage connecting a gas inlet and a first valve; and a second gas connecting a first valve and a gas outlet. A flow path, a gas flow path branched from the first gas flow path and connected to the second valve, a gas flow path connected to the third valve and connected to the second gas flow path, Third connecting the second valve and the first raw material container connection port
A gas flow path branched from the third gas flow path and connected to the fourth valve; and a fourth flow path connecting the second material container connection port and the third valve.
And a gas flow path branched from the fourth gas flow path and connected to the fifth valve, and the first to fifth five valves are one The structure is fixed to the valve support.

[Action]

FIG. 1 is a view schematically showing a valve connection shape in the present invention. As is clear from the comparison of FIG. 3 with FIG. 3, the joint existing between the valve 12 and the valve 14 is not used in the present invention, and the valve 14 connects the valve 12 and the external connection port E. Directly connected to piping. Also, valve 15
The same applies to the relationship between the valve and the valve 13. The piping section 31 including the valves 11 to 15 is integrated and attached to one support.

In this way, by adopting a shape that branches directly from the pipe without using a joint, the internal surface area of the pipe system is reduced, and a structure in which a leak easily occurs is avoided. As a result, the release of impurities from the tube wall and the entry of impurities due to leakage are suppressed, and the source gas supplied to the reaction chamber is maintained at a high purity.

〔Example〕

In the piping system in the embodiment of the present invention, the connection structure of the part related to the integrated structure of the valves is as shown in FIG. 1, and the purpose of use of each valve and the reason why such a connection structure is effective. Is as described above.

The first point of particular interest in the valve connection structure of the present invention is
The point is that the valve 12 and the valve 14 are directly connected by using a three-way type conduit, and the pipe having the external connection port E is also integrated. A similar structure can be seen between the valves 13 and 15 and the external connection port F. 3 of these
The rectangular conduit is formed by means such as welding, and the shape inside the pipe is simplified as compared with the connection by a joint. As a result, the dead space of the gas flow is eliminated, and no leak is generated, so that the quality of the raw material gas is kept extremely high.

FIG. 2 is a perspective view showing an appearance of an integrated valve structure according to one embodiment of the present invention. The five valves 11 to 15 are housed inside a box-shaped support 30 and only the knobs of these valves are visible in the figure. Pipe ends A, B, C, D, E, and F connected to other piping systems have flange shapes conforming to CAJON standards known as VCR joints, and the outer diameter of the pipe is 1 / 4 inches.

〔The invention's effect〕

In one embodiment of the present invention, the internal surface area of the pipe is reduced by 15 to 20 cm ² as compared with the conventional configuration, but the complicated internal shape and the risk of leak generation when using a joint are eliminated. In consideration of the above, the effects more than those shown in the figures were obtained, and it became possible to supply a high-quality source gas to the vapor phase growth apparatus.

[Brief description of the drawings]

FIG. 1 is a view showing a pipe connection of a valve integrated configuration of the present invention, FIG. 2 is a perspective view showing an appearance of an embodiment of the present invention, FIG. 3 is a view showing a conventional valve connection, and FIG. Diagram showing the basic valve arrangement of the piping system, FIG. 5 is a diagram showing the realistic minimum number of valve arrangements, in which 10 is a carrier gas container, 11 to 17 are valves, and 20 is raw material. A container, 21 is a reaction chamber, 22 is a joint, 30 is a support, and 31 is an accumulation part.

Claims (1)

(57) [Claims] A first gas flow path connecting the gas inlet A to the first valve 11; a second gas flow path connecting the first valve 11 to the gas outlet B; A gas flow path branched from the gas flow path and connected to the second valve 12; a gas flow path connected to the third valve 13 and coupled to the second gas flow path; A third gas flow path connecting the first raw material container connection port E, a gas flow path branched from the third gas flow path and connected to the fourth valve 14, and a second raw material container connection port A fourth gas flow path connecting F to the third valve 13; a gas flow path branched from the fourth gas flow path and connected to the fifth valve 15; The first to fifth five valves are connected to one valve support 30.
An integrated valve structure, characterized by being supported by: