JPS59119826A - Vapor growth apparatus - Google Patents

Abstract

PURPOSE:To easily realize the purging process within a short period of time by providing a purging gas supply pipe which is capable of supplying a purging gas in the clearance between the external and internal pipes of a double-pipe type vapor growth apparatus. CONSTITUTION:An external pipe 1 of reaction pipe has a cap 11 of external pipe of reaction pipe which opens or closes the reaction pipe, inlet hole 12 and exhausting hole 13 of external pipe of reaction pipe. A substrate 4 to be processed placed on a base material board 3 is sealed within the inside of internal pipe 2 prepared as the protection pipe. A source chamber 5 accommodating sources 61, 62 is provided with the inlet holes 51, 52. A purging gas is supplied to the clearance between the external pipe 1 and internal pipe 2 through a branching pipe 7 by the purging gas supply pipe 7. The number of purging gas supply pipes 7 is not limited to two.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a vapor phase growth apparatus. In particular, it relates to improvements in vapor phase growth and standing in a double tube system.

(2) Background of the technology A vapor phase growth apparatus is a container (reaction tube) made of chemically stable materials such as quartz glass.
A base material such as a semiconductor substrate is sealed in the base material, and each constituent element substance constituting the semiconductor etc. to be deposited and grown on the base material is fed in gaseous form, and the composition % elementary substance is introduced into the feed path. Deposition growth axis region 1 An apparatus for depositing and growing a desired substance, particularly a compound semiconductor, etc., on the base material by controlling the temperature of a certain base material region to a temperature suitable for the occurrence of a desired reaction. In a vapor phase growth apparatus, it is desirable that the deposition growth occur centrally on the base material, but in reality, it is unavoidable that deposition growth occurs not only on the support frame of the base material but also on the inner wall of the reaction tube. . For this reason, a double-tube system is often used in which the reaction tube is a double-tube structure and the deposition and growth is allowed to occur only in the protective tube with the inner tube 1.

(3) Prior Art and Problems Two typical examples of a two-M tube type vapor phase growth apparatus in the prior art are shown in FIGS. 1(a) and 1(b). In the figure, l is the reaction tube outer tube, If is a reaction tube outer tube cap, and the reaction tube outer tube can be opened and closed. 12.13
are the inlet and exhaust holes of the outer tube of the reaction tube. Reference numeral 2 denotes a storage fav which is an inner tube, and a substrate to be processed 4 placed on a substrate mount 3 is sealed inside the storage fav.

Reference numeral 5 denotes a source chamber 9 for containing constituent element substances (sources) 61,62, and 51,52 are inlet holes for the source chambers. The difference between figure (a) and figure (b) is
In FIG. 11, the cross section of the processing target substrate accommodating area of the protection tube 2 is narrowed.

In such a conventional two-claw tube type vapor phase growth system, the substrate 4 to be processed and the sources 61 and 62 are replaced.
At this time, the vacuum inside the reaction tube is temporarily broken and air is filled. Therefore, prior to the deposition growth, the temperature of the reaction tube is lowered so as not to satisfy the neutrality of the reaction, and hydrogen (N2) is injected from the inlet hole 12, 51, 52. A carrier gas such as , or an inert gas such as nitrogen (N2) is supplied to expel undesirable gases from inside the reaction tube. However, especially the oxygen (02) and moisture (N20) remaining in the area sandwiched between the reaction tube outer tube 1 and the protection tube 2
It is difficult to remove such substances, and the above purging process takes 1 to 2 hours. In other words, if the deposition growth process is started without forming a sufficient nozzle for 1 to 2 hours, the quality of the deposits such as semiconductors to be deposited and grown will not be stable. The gap between the inner wall of the reaction tube outer tube and the outer wall of the protection tube is 0.5 to 2 (rn
This is because it is as small as .m).

(4) Purpose of the Invention The purpose of the present invention is to eliminate this drawback.1) The purpose of the present invention is to facilitate the purging step which is performed after exchanging the substrate, source, etc. and prior to the start of the deposition growth step. It is an object of the present invention to provide a double-tube type vapor phase growth apparatus that has advantages that can be achieved in a short period of time.

(5) Structure of the Invention The above object is to provide a nozzle gas which can supply purge gas to the gap between the outer tube and the inner tube in a double tube type vapor phase growth apparatus having a protection tube inside the outer tube of the reaction tube. This is achieved by providing a supply pipe.

The quantity, position, shape, etc. of the above-mentioned purge gas supply pipes vary widely as described in the examples below, but are not limited to the examples described below.

(6) Embodiments of the Invention Hereinafter, vapor phase growth apparatuses according to a few embodiments of the present invention will be further described with reference to the drawings.

Referring to FIG. 2, a conceptual sectional view of a vapor phase growth apparatus according to an embodiment of the present invention is shown. In the figure, 1 is an outer tube of the reaction tube, and 11 is a cap of the outer tube of the reaction tube, which enables the reaction tube to be opened and closed.

Reference numerals 12 and 13 are the popular hole and exhaust hole of the outer tube of the reaction tube. 2
There is an inner tube f, in which a substrate 4 to be processed placed on a substrate mount 3 is sealed. 5 is sauce 61.
62, 51.52
is the inlet hole of the source Cheno ζ−. Reference numeral 7 denotes a purge gas supply pipe according to the gist of the present invention, which supplies purge gas to the gap between the outer pipe and the inner pipe through branch pipes such as 71. In the figure, two gas supply pipes 7 are shown, but the number is not limited to two.

3 is a conceptual sectional view of a vapor phase growth apparatus according to another embodiment of the present invention. The difference from the one shown in Figure 2 is: ・ξ−
A plurality of di-gas supply pipes 7' are provided so as to blow out di-gas at once in the direction along the gap, thereby improving the .xi.-di effect of the gap.

Referring to FIG. 4, there is a conceptual sectional view 1 of a vapor phase growth apparatus according to still another embodiment of the present invention. The difference from the embodiment shown in FIGS. 2 and 3 is that a ring-shaped purge gas distribution section 71' is provided at the tip of the nocuzi gas supply pipe 7' surrounding the protection tube 2.
A plurality of purge gas discharge pipes 71 are provided in an area facing the gap of this ring-shaped A-di gas distribution section 71''.

In any of the above embodiments, in the prior art, the /e-di gas is forcibly supplied to the gap between the outer tube and the inner tube, where oxygen (0□), moisture (N20), etc. tend to accumulate. Such undesirable gases can be easily removed in a very short time, contributing to improved efficiency of the deposition growth process.

Incidentally, in any of the above embodiments, the shape of the protective tube is cylindrical, but it goes without saying that this has a negative side support.

(7) As described in detail, the present invention provides benefits that can be achieved easily and in a short period of time by the e-direction step performed after exchanging the substrate, source, etc. and prior to the start of the deposition growth step. It is possible to provide a double tube type vapor phase growth apparatus having the following.

[Brief explanation of the drawing]

FIGS. 1(a) and 1(b) are conceptual cross-sectional views of a conventional double tube type vapor phase growth apparatus. 2.3 and 4 are conceptual cross-sectional views of a double tube type vapor phase growth apparatus according to an embodiment of the present invention. 1...Reaction tube outer tube, 11...Reaction tube outer tube cap, 12...Reaction tube outer tube inlet hole, 13...Reaction tube outer tube exhaust hole, 2...4M protection Pipe, 3...Base material frame, 4
...Substrate to be processed, 5...Source chain-151
, 52...Inlet hole of source chain, 61.62
...Source, 7...Noξ-di gas supply pipe, 71...
・Branch pipe, 7'... Purge gas supply pipe, 7'... Digas supply pipe, 71'... Purge gas distribution section, 71
...Niji gas discharge part.

Claims (1)

[Claims] A double tube type vapor phase growth apparatus having a protection tube inside the outer tube of the reaction tube, characterized in that it has a purge gas supply tube for supplying purge gas to the gap between the outer tube and the inner tube.