JPS6194319A - Evaporator of volatile matter - Google Patents

Abstract

PURPOSE:To make the exchange of an evaporator easy by connecting a bypass pipe which has a valve at the center outside of the valves of two gas pipes which are connected to other equipment in the evaporator of a volatile matter used for epitaxial growth, CVD, etc. CONSTITUTION:An evaporator used for epitaxial growth, CVD, etc. has a container 4 filled with a volatile matter 3 and a gas pipe 1 which has a valve 2 outside and is inserted in the volatile matter 3 and a gas pipe 5 which has also a valve 6 outside and is inserted in the vapor are attached to the container 4. A carrier gas supply pipe 9 at the side of the valve 2 and a vapor supply pipe 10 at the side of the valve 6 are connected with joints 7 and 8. In this case, a bypass pipe 21 which has a valve 22 at the center is provided between the gas pipes 1 and 5 outside of the valves 2 and 6. If the valves 2, 6 are closed and the valve 22 is opened, a carrier gas flows in the pipes 1 and 5 and no vapor stays in these pipes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to vapor phase epitaxial growth and chemical transport growth (CVD).
The present invention relates to a device for vaporizing volatile substances used as raw material gas for deposition, etc.

Conventional configurations and their problems Vapor phase epitaxial growth of compound semiconductors (e.g. halide vapor phase epitaxial growth method and organometallic pyrolysis method)
Electrode formation by the vn method (for example, formation of molybdenum electrodes)
In the manufacturing process of compound semiconductor devices and silicon semiconductor devices, volatile substances are vaporized and used as raw material gas.

A conventional volatile substance vaporization device will be described below with reference to FIG. 1 is a carrier gas inflow bottom side gas pipe, 2
is a valve on the carrier gas inlet side, 3 is a volatile substance, 4 is a container containing the volatile substance, 6 is a gas pipe on the carrier gas outlet side, 6 is a valve on the carrier gas outlet side, 7 and 8 are connected to other gas pipes. This is the joint part. As shown in Fig. 1, the conventional volatile substance vaporization apparatus connects gas pipes 9 and 1o of a vapor phase growth apparatus etc. with joints 7 and 8, and supplies carrier gas from the gas pipe 1 side on the carrier gas inlet side. The carrier gas is fed into a chamber 4 containing a volatile substance through a valve 2, vaporizes the volatile substance 3, and then flows out through the valve and the like from a gas pipe on the carrier gas outlet side to the apparatus.

However, in such a structure, after the supply of the volatile substance is finished, the carrier gas containing the vaporized gas of the volatile substance remains in the portion 12.13 of the gas pipe. For this reason,
When replacing the volatile substance vaporizer, when the joints 7 and 8 are removed, the vaporized gas remaining in the gas pipe leaks out. This gives the worker 11
However, if the volatile substance was an organic metal, it would react violently with the air (oxygen) and spontaneously combust, making it very dangerous. In addition, since volatile substances remain in the gas pipe, they may adhere to the pipe wall and contaminate the pipe interior, or if used as a raw material gas for mixed crystal growth, they may change the mixed crystal ratio. Ta. Therefore, it has been difficult to control the composition of the mixed crystal, the amount of impurity doping, and the steepness of the interface when growing a multilayer thin film.

Therefore, as shown in Fig. 2, a bypass pipe 14 is provided to directly connect the gas pipes 9 and 10 in the piping on the side of the growth apparatus, etc. After the volatile substances have been vaporized, the carrier gas is flowed through the bypass pipe 14 to remove the residual gas. A method of removing the residual gas was also taken, but it took a considerable amount of time to completely remove the residual gas because the carrier gas did not flow through the part 16.16 of the gas pipe. There is also a method of exhausting the residual gas in the gas pipe using a vacuum pump or the like, but this method requires complicated equipment and time. Furthermore, there is a possibility that vapor from the oil used in the pump will enter the gas pipe, which is not desirable.

OBJECT OF THE INVENTION The present invention solves the above-mentioned conventional problems by preventing vaporized gases of volatile substances from remaining in the carrier gas inflow bottom gas pipe and the carrier gas outflow bottom gas pipe, or To provide a volatile substance vaporizer that can keep the inside of a gas pipe clean at all times by easily removing residual gas, and can safely replace the volatile substance vaporizer.

Structure of the Invention The present invention includes valves on the inlet side and the outlet side of the gas flow,
In a volatile substance vaporizer that is connected to the gas piping of another device, the gas pipe between the valve on the gas flow inlet side and the gas pipe joint on the gas inlet side, and the gas pipe on the gas flow outlet side. Vaporization of volatile substances characterized by comprising a bypass gas path that directly connects a gas pipe between a valve and a gas pipe joint on the gas outlet side, and further comprising a valve in the middle of the bypass gas path. It is a device.

In addition, in a volatile substance vaporization device that is equipped with valves on the inlet and outlet sides of the gas flow and is used by connecting to the gas piping of another device, the valves on the inlet and outlet sides of the gas flow divide the gas flow into two. A two-way switching valve that can be switched in one direction, and one direction of each is connected to a container containing a volatile substance, and the other directions are directly connected to each other to form a bypass gas path. This is a device for vaporizing volatile substances.

In addition, in a volatile substance vaporization device that is used by installing a valve on the inlet side and the outlet side of the gas flow and connecting it to the gas piping of another device, it is also possible to install a valve on either the intake side or the outlet side of the gas flow. is a two-way valve capable of switching gas flow in two directions, one direction of which is connected to a container containing a volatile substance, and the other direction is connected to a valve other than the two-way valve. This volatile substance vaporization device is characterized in that it is directly connected to a gas path between the gas pipe joint and the gas pipe joint part, forming a bypass gas path.

DESCRIPTION OF EMBODIMENTS A specific embodiment of the volatile substance vaporization apparatus according to the present invention is shown in FIG. In FIG. 3, the same parts as in FIG. 1 are given the same numbers. Reference numeral 21 denotes a gas pipe as a bypass gas path that directly connects the carrier gas inflow side gas pipe 1 and the carrier gas outlet side gas pipe 6, and this gas pipe 21 is provided with a valve for turning on and off the flow of the carrier gas. There are 22.

If the vaporizer has the above structure, the carrier gas inlet valve 2 and the carrier gas outlet valve 6 are closed and the valve 22 is opened when the supply of volatile substances is finished, thereby allowing the carrier gas to flow into the gas pipe 21. . Therefore, since the carrier gas flows through the gas pipes 1 and 6, no vaporized gas of volatile substances remains. Therefore, when replacing the vaporizer, even if the joints 7 and 8 are removed, volatile substances will not leak out and the work can be carried out safely.Also, since no residual gas remains in the gas pipe, the inside of the gas pipe can be cleaned. Can be kept clean at all times.

Another embodiment of the invention is shown in FIG. In FIG. 4, the same parts as in FIGS. 1 and 3 are designated by the same numbers. Third
The difference from the figure is that in Figure 4, the carrier gas input valve 31 and the carrier gas input valve 32 are special valves that can switch the gas flow in two directions (Figure 6 shows the basic schematic structure). ), one direction of each of these two-way switching valves is connected to the container 4 containing the volatile substance, and the other direction is provided with a bypass gas path 21 that is directly connected to each other. be. A schematic structure of this two-way switching valve is shown in FIG. By operating this valve, the valve 50 inside moves up and down. Due to the movement of this valve 60, gas entering from the inlet 51 is guided to either the outlet 52 or the outlet 53 and exits. In this figure, for example, when valve 50 is down, gas is exhausted through outlet 52.

Then, when the top of the valve 6o reaches the 9-dotted line, the gas flows out from the outlet 5.
It is discharged from 3. Therefore, by operating the two-way switching valves 31 and 32, the carrier gas can be sent to the container 4 containing the volatile substance or to the bypass gas path 21. Compared to the example, fewer valve operations are required, and vaporized gas of volatile substances does not remain in the gas pipes 1 and 5.

Therefore, the same effect as the embodiment shown in FIG. 3 can be obtained.

Further, the two-way switching valve may be used only on either the carrier gas inlet side or the outlet side, and a normal valve may be used on the other side. An example is shown in FIG. This figure shows a case where a two-way switching valve 61 is used on the carrier gas inlet side. As shown in this figure, the two-way switching valve 6
One side of 1 is connected to a container 4 containing a volatile substance,
The other direction is directly connected to the gas pipe 5 on the carrier gas outlet side between the valve 6 on the carrier gas outlet side and the gas pipe joint part 8,
A gas path 21 for bypass is formed.

It goes without saying that even with such a structure, the same effects as the embodiment shown in FIG. 3 can be obtained. Also, contrary to FIG. 6, the same effect can clearly be obtained even if the carrier gas is used on the outlet side and a normal PALEP is used on the inlet side.

In addition, the previous valves 2, 6, 22, 31.32゜6
1 may be a manual valve, a solenoid valve, or a pneumatically operated valve.

Figure 7 shows the metal organic pyrolysis method (MOCVD) in which the compound semiconductor InP is epitaxially grown using an organic metal, triethyl indium (TRI) as a volatile substance.
A case in which the present invention is used is shown below. In addition, Figures 1 and 3
Parts that are the same as those in the figure are given the same numbers.

Before growing InP, the flow rate of the carrier gas (H2) is controlled from the hydrogen pump 41 using the mass flow 42, and the gas pipe 9,
1.21.5.10 and 43 to the exhaust gas treatment device 44. This is because the flow rate of the carrier gas sent to the TRI is controlled in advance.

At the start of InP growth, by opening the valves 2 and 6 and closing the valve 22, the carrier gas is sent to the TEI vaporizer 46 and TEI is vaporized. At the same time, by closing the valve 46 and opening the valve 47, vaporized TEI gas is sent to the reactor 48, and the I
Grow nP with Evitakin. When the growth is finished, valve 46 is opened and valve 47 is closed, and valves 2 and 6 are closed.
By opening 2, the residual TRI gas in the gas pipe is caused to flow to the exhaust gas treatment device 44 by the carrier gas. Therefore, no vaporizing force y remains in the gas pipes 9.1.21.5, 10. In addition, 49 is a PH3 (honufin cylinder) which is a raw material gas for P, 70 is a substrate, 71 is a sasse 7' tough 2 is a heating device, and 73 is a vacuum pump for reduced pressure growth.

According to the embodiments described above, the TEI vaporizer can be replaced easily and safely, and contamination of the gas pipe can be prevented. In addition, as an example, M using TRI
Although only the case using the OCVD method will be explained, it is not limited thereto.
The present invention can also be applied to vaporizers such as V-group I:I'y' heptides such as AS Brs, and MOCJ5 used for electrode formation by CVD method.

Effects of the Invention The volatile substance vaporization device according to the present invention has a bypass gas path that directly connects a carrier gas inlet side gas pipe and a carrier gas outlet side gas pipe, and By providing a two-way switching valve that allows the gas to flow into either the container or the bypass gas path, vaporized gas of volatile substances can be introduced into the carrier gas inlet side gas pipe and the carrier gas outlet side gas pipe. There will be no residue left behind. This allows the volatile substance vaporizer to be replaced safely and easily. In addition, it prevents contamination inside the gas pipe due to the adhesion of residual gas to the gas pipe wall, and also allows precise control of mixed crystals, impurity doping amount, and interface steepness in the case of multi-layer single-source growth. It is very large.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a conventional volatile substance vaporization apparatus, Fig. 2 is a connection diagram of the conventional volatile substance vaporization apparatus to the growth apparatus side piping, and Fig. 3 is an embodiment of the present invention. Fig. 4 is a schematic diagram of a volatile substance vaporization apparatus according to a second embodiment of the present invention, and Fig. 6 is a schematic diagram of a volatile substance vaporization apparatus according to a second embodiment of the present invention. Fig. 6 is a schematic structural diagram of a volatile substance vaporization apparatus according to a third embodiment of the present invention, and Fig. 7 is a schematic diagram of a volatile substance vaporization apparatus according to an embodiment of the present invention in an MOCVD apparatus. It is a schematic diagram of a gas piping system when connected. 1... Gas inlet side gas pipe, 2... Gas inlet side valve, 3... Volatile substance, 4...
...Container, 5...Gas outlet side gas pipe, 6
...Gas outlet side valve, 7, 8...
Gas pipe joint part, 21... Bypass gas route,
22... Valve, 31, 32.61...
Two-way switching valve. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 21? ? Figure 4 Figure 5 ↓

Claims (3)

[Claims] (1) In a volatile substance vaporization device that is equipped with a valve on the inlet side and an outlet side of the gas flow and is used by connecting to the gas piping of another device, the valve on the inlet side of the gas flow and the valve on the gas inlet side are used. a bypass gas path that directly connects a gas pipe between the gas pipe joint and a gas pipe between the valve on the outlet side of the gas flow and the gas pipe joint on the gas outlet side; A volatile substance vaporization device characterized by having a valve in the middle of a path. (2) In a volatile substance vaporization device that is provided with valves on the inlet and outlet sides of the gas flow and is used by being connected to the gas piping of another device, the valves on the inlet and outlet sides of the gas flow A two-way switching valve capable of switching between two directions, characterized in that one direction of each is connected to the container containing the volatile substance, and the other directions are directly connected to each other to form a bypass gas path. Vaporization equipment for volatile substances. (3) In a volatile substance vaporization device that is equipped with a valve on the inlet side and an outlet side of the gas flow and is used by connecting to the gas piping of another device, one of the gas flow inlet and outlet sides is connected to the gas piping of another device. the valve is a two-way switching valve capable of switching gas flow in two directions, one direction of the two-way switching valve being connected to the container containing the volatile substance and the other direction not being the two-way switching valve; A volatile substance vaporization device characterized by being directly connected to a gas path between a valve and a gas pipe joint to form a bypass gas path.