JPH0485817A - Gas transfer apparatus - Google Patents

Abstract

PURPOSE:To obtain a gas feeder capable of detecting leakage to the outside and the internal leakage of a valve by installing a connecting section connected to a gas bomb for inspection to a tube brought near to a gas bomb while mounting a permanent vacuum line bonded with a high-vacuum pump, setting up a gas detector for inspection to the high-vacuum pump, and detecting a gas for inspection flowing into the tube. CONSTITUTION:Helium is blown upon from the connecting sections of each valve B1-B11 and tubes P and the outsides of the mutual connecting sections of the tubes P under the state in which the insides of the tubes P are brought to a high vacuum pump 6 in order to detect leakage to the outside, thus supplying a helium detector 11 with He, then detecting the presence of leakage to the outside. When the valve B2 is closed, the valve B9 is opened, valves except a valve B13 are closed and a valve B14 is opened and He is fed, He is detected by the helium detector 11 when there is internal leakage in the valve B2 in order to detect internal leakage. When the valve B9 is closed, the valve B2 is opened, the valves except the valve B13 are closed and the valve B14 is opened and He is supplied, the presence of internal leakage in the valve B9 can be detected.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is applicable to MOCVD (metal organic chemical vapor deposition)
The present invention relates to a gas supply device for supplying gas to a vacuum device used in the E (molecular beam epitaxy) method, etc., and particularly relates to a gas supply device having an internal leak detection mechanism of a valve.

(Prior Art) An example of a gas supply device used in the conventional MOCVD method is shown in FIG. 2 and will be described below.

Hydrogen gas (H2) supplied from hydrogen cylinder 1 is passed through tube P and MFC (mass flow controller dual flow meter) 2.
Supplied to the reactor (reactor) 3 via a to 2C (
In the figure, there are 3 systems, but there are actually more systems). Note that some of the hydrogen gas output from MFC 2b is a metal-organic material ('MO
) is supplied to the bubbler 4 in which it is stored, and by bubbling there, the organic metal material equivalent to the vapor at that temperature is introduced into the carrier gas, and then this carrier gas is supplied to the reactor 3. .

Furthermore, other gases (for example, A
sH3) is also connected to reactor 3 from cylinder 5 via MFC2d.
(again, there are actually many strains).

Then, while controlling the flow rate and pressure of the gas in the reactor 3 using the exhaust pump 12, the wafer (not shown) in the reactor 3 is heated and the gas supplied from the tube P reacts with the semiconductor. We are doing manufacturing.

In such a gas supply device, it is necessary to check for leaks at the contact portions between each of the valves 81 to Bl+ and the tubes P, and at the connection portions between the tubes P.

Therefore, conventionally, a part of the tube P has a joint 7 for leak checking, and a He leak detector (detector) 8 is connected through this joint 7, and the inside of the tube P is connected to a high vacuum pump 6 and a leak detector. 8 with the attached pump (not shown), each valve 81 to B
The presence or absence of a leak is detected by spraying helium (He) from the outside onto the connection between the l+ and the tube P and the connection between the tubes P and detecting the helium entering the tube P using the He leak detector 8. was.

(Problems to be Solved by the Invention) In conventional gas supply devices, leaks to the outside from the connecting parts between each valve and the tubes and the connecting parts between the tubes can be detected, but internal leaks from the valves, that is,
It was not possible to confirm whether the valve was completely closed or not.

When there is a leak to the outside, for example, oxygen gets mixed into the semiconductor crystal film (not shown) inside the reactor 3, causing characteristic deterioration, and furthermore, when there is an internal leak in the valve, the supply is stopped. However, there have been problems in that the composition of the semiconductor crystal film may be misaligned due to mixed materials, and the laminated thin film may not be able to be switched instantly.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a gas supply device that can detect not only external leaks but also internal leaks of a valve.

(Means for solving the problem) As a means for achieving the above object, there is provided a tube to which a material gas and a carrier gas are supplied from a gas cylinder, an organic metal material is supplied from a bubbler, and a valve for opening and closing this tube. , a reactor to which gas is supplied from the tube to grow semiconductor crystals, a high vacuum pump to bring the reactor to a vacuum state, and an exhaust pump to adjust the flow rate and pressure of the gas in the reactor. and a gas supply device for manufacturing semiconductors in the reactor, wherein the tube close to the gas cylinder is provided with a connection part for connecting to a testing gas cylinder filled with a predetermined gas, A permanent vacuum line connected to the high vacuum pump is provided in the tube, and a test gas detection device is provided in the high vacuum pump to detect the test gas flowing into the tube. The purpose is to provide a supply device.

(Example) An example of the gas supply device of the present invention is shown in FIG. 1 and will be described below. Note that the same components as those in the conventional example described above are given the same reference numerals, and the explanation thereof will be omitted.

In this embodiment, a helium (HC) cylinder 9 is connected to the tube P closest to the hydrogen cylinder 1 (helium supply line) in the conventional apparatus, and a permanent vacuum is installed instead of the leak check joint 7. A line 10 is provided, and this permanent vacuum line 10 is connected to a high vacuum pump 6, and a helium detection device 11 such as a Q-mass (four-pole mass spectrum) is connected to the high vacuum pump 6.

When using such a gas supply device, normally, by keeping valve A, which is a supply valve from the helium cylinder 9, closed, the gas supply device can be used in the same manner as before.

In order to detect leakage to the outside, as in the past, the inside of the tube P is brought to a high vacuum by the high vacuum pump 6, and the connection parts between each valve 81 to B I+ and the tube P and the tubes P are connected to each other. By spraying helium (He) from the outside of the connecting part of be able to.

Next, a method for detecting internal leaks will be explained.

First, valve B2 is closed, valve B9 is opened, and all other valves except valve B13 are closed. Then, when valve B4 is opened to supply He, if there is an internal leak in valve B2, He is detected by the helium detection device 11. Furthermore, if valve B9 is closed and valve B2 is opened, and all other valves except valve B13 are closed, valve B14 is opened to supply He, it is possible to detect the presence or absence of an internal leak in valve B9. .

By repeating this operation for each of the valves 82 to B I+, internal leaks in all the valves can be detected.

Furthermore, the present invention can of course be applied not only to a gas supply device for a vacuum device used in the MOCVD method, but also to a gas supply device for other vacuum devices such as the MBE method.

(Effects of the Invention) The gas supply device of the present invention not only prevents leakage to the outside, but also prevents leakage to the outside.
Since it is configured to be able to detect internal leaks, it is possible to reliably detect valve failures due to changes over time, and it is possible to quickly and reliably replace defective valves, which was conventionally done by guessing.

When a deviation in the composition of the semiconductor crystal film produced in the reactor occurs, it can be immediately determined whether the cause is due to internal leakage or other factors.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the gas supply device of the present invention, and FIG. 2 is a schematic diagram showing a conventional example. 1...Hydrogen cylinder, 2a-2d...MFC13...
・Reactor (reactor), 4...liquid metal tank, 5...
(A s H3) Cylinder, 6... High vacuum cylinder 1.7.
...Leak check fitting, 8.He leak detector, 9.Helium cylinder (inspection gas cylinder), 10.
... Permanent vacuum line, 11... Helium detection device (inspection gas detection device),
12...Exhaust bonder, B;~Bu...Valve, P.
··tube. Figure 1 Patent Applicant Victor Japan Co., Ltd. Figure 2

Claims (1)

[Claims] Material gas and carrier gas are supplied from a gas cylinder,
A tube to which an organic metal material is supplied from a bubbler, a valve to open and close this tube, a reactor to which gas is supplied from the tube to grow semiconductor crystals, and a high vacuum pump to bring this reactor into a vacuum state. and an exhaust pump that adjusts the flow rate and pressure of gas in the reactor, the gas supply device for manufacturing a semiconductor in the reactor, the gas supply device having a predetermined amount of gas in the tube adjacent to the gas cylinder. A connection part for connecting to a test gas cylinder filled with gas is provided, a permanent vacuum line connected to the high vacuum pump is provided in the tube close to the reactor, and a test gas detection device is provided in the high vacuum pump. A gas supply device configured to detect a test gas flowing into the tube.