JPH10317145A - Vapor growth device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor growth device forming coating in which the concn. of impurities is uniform and coating thickness is uniform. SOLUTION: As for a vapor growth device 1, a sample is placed on a boat at the center part of an axis in a core tube 4, a compound gas is fed from a gas introducing tube 6 into the core tube 4, and the sample on the boat 5 is grown in vapor phases to form coating. A nozzle 7 provided on the tip part of the gas introducing tube 6 is arranged along the inner circumferential face of the core tube 4, and an ejector formed on the nozzle 7 is formed toward the center direction of the axis in the core tube 4 and is also formed slantingly at prescribed degrees in the circumferential direction toward the center of the axis. Thus, the compound gas injected into the core tube from the nozzle 7 of the gas introducing tube 6 proceeds to the center direction of the axis of the core tube 4, furthermore rotates in the core tube 4 and is uniformly diffused toward the sample on the boat 5, by which the thickness and concn. of impurities formed on the sample can be made uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor phase growth apparatus, and more particularly, to uniformly diffuse a gas into a sample in a furnace tube to form a film having a uniform impurity concentration and a uniform film thickness. The present invention relates to a vapor growth apparatus.

[0002]

2. Description of the Related Art As a technique for growing a single crystal or a polycrystal on a substrate by utilizing a chemical reaction in a gas phase, there is a chemical vapor deposition (CVD) technique. The wafer is heated, and the compound gas is decomposed by the thermal energy generated from the surface to form a thin film on the surface of the sample. Heating is an important factor.

Therefore, a core tube for vapor phase growth (see Japanese Patent Application Laid-Open No. 7-183232) has been proposed. In this furnace tube for vapor phase growth, a hollow tube-shaped furnace tube body is coaxially inserted into a hollow tube-shaped gas introducing means, and a space between an outer peripheral surface of the furnace tube tube and an inner peripheral surface of the gas introducing device is provided. At least 4
By forming these passages, the outer peripheral surface of the furnace core tube and the inner peripheral surface of the gas introducing means are brought into close contact with each other in at least four places, and one end of each passage and one end of the furnace core tube communicate with each other.
That is, in this furnace tube for vapor phase growth, the gas inlet is inserted coaxially with the furnace tube main body to achieve uniform gas.

[0004]

However, in such a conventional vapor phase growth apparatus, since the gas inlet is inserted coaxially with the core tube body, the gas inlet is inserted into the core tube from the gas inlet. There is a problem that the introduced gas flows along the furnace tube, and the thickness and concentration of impurities near the center of the sample become non-uniform.

In view of the above, according to the first aspect of the present invention, the nozzle at the tip of the gas introduction tube for introducing gas into the furnace tube is arranged along the inner peripheral surface of the furnace tube, and the injection port of the nozzle is connected to the shaft of the furnace tube. By forming an opening toward the center, the gas is injected from the nozzle orifice toward the axial center of the furnace tube, and the gas is uniformly diffused into the sample stored in the furnace tube, and It is an object of the present invention to provide a vapor phase growth apparatus for making the thickness and concentration of the formed impurities uniform.

According to a second aspect of the present invention, the injection port is formed toward the axial center of the furnace tube and in a direction inclined at a predetermined angle in the circumferential direction of the furnace tube with respect to the axial center. The gas is injected from the nozzle orifice toward the axial center of the furnace tube, and the gas is swirled in the furnace tube to diffuse the gas more evenly with respect to the sample stored in the furnace tube, thereby forming the sample. It is an object of the present invention to provide a vapor phase growth apparatus that makes the thickness and concentration of impurities more uniform.

According to the third aspect of the present invention, by arranging a plurality of gas introduction pipes, the gas is injected from the nozzles of the plurality of gas introduction pipes toward the axial center of the furnace tube, and is housed in the furnace tube. The gas more evenly to the sample
It is an object of the present invention to provide a vapor phase growth apparatus that makes the thickness and concentration of impurities formed on a sample more uniform.

[0008]

According to a first aspect of the present invention, there is provided a vapor phase growth apparatus according to the first aspect of the present invention, in which a core tube formed in a hollow tube shape and containing a sample to be vapor-phase grown is inserted into the core tube. And a gas introduction tube for introducing a predetermined gas into the furnace tube, wherein the gas introduction tube is provided at a tip end inserted into the furnace tube, at an inner peripheral surface of the furnace tube. A nozzle having a predetermined number of injection ports disposed along the nozzle, wherein the injection ports are formed so as to open toward the axial center of the furnace tube, thereby achieving the above object. .

According to the above construction, the nozzle at the tip of the gas inlet tube for introducing gas into the furnace tube is arranged along the inner peripheral surface of the furnace tube, and the injection port of the nozzle is directed toward the axial center of the furnace tube. The gas is injected from the nozzle orifice in the axial center direction of the furnace tube, and the gas can be uniformly diffused into the sample stored in the furnace tube. It is possible to make the thickness and concentration of the impurities to be uniform.

In this case, for example, as described in claim 2, the injection port is directed toward the axial center of the core tube and is inclined at a predetermined angle in the circumferential direction of the core tube with respect to the axial center. It may be formed toward the direction.

According to the above configuration, the injection port is formed toward the axial center of the furnace tube and in a direction inclined at a predetermined angle in the circumferential direction of the furnace tube with respect to the axial center. The gas is injected from the injection port toward the axial center of the furnace tube, and the gas is swirled in the furnace tube so that the gas can be more evenly diffused into the sample stored in the furnace tube and formed on the sample. The thickness and concentration of the impurity to be formed can be made more uniform.

Further, for example, as described in claim 3, a plurality of the gas introduction pipes may be provided, and each of the gas introduction pipes may have the nozzle at a tip end thereof.

According to the above configuration, since a plurality of gas introduction pipes are provided, the gas is injected from the nozzles of the plurality of gas introduction pipes in the axial center direction of the furnace tube, and the sample housed in the furnace tube is provided. Gas can be diffused more uniformly, and the thickness and concentration of impurities formed in the sample can be made more uniform.

[0014]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 4 show a vapor phase growth apparatus to which an embodiment of the vapor phase growth apparatus of the present invention is applied. In FIG. 1, in a vapor phase growth apparatus 1, a substantially cylindrical furnace body 3 whose upper part is formed in a hemispherical shape and is closed is disposed on a cap 2, and the furnace body 3 is closed in a cylindrical shape. Furnace tube 4 is stored.

In the core tube 4, a boat 5 is arranged in the axial direction at the center of the core tube 4, and a plurality of samples,
For example, a Si wafer is placed.

A plurality of, for example, four gas introduction pipes 6 are inserted into the furnace core tube 4 from outside the furnace body 3, and the gas introduction pipes 6 are provided above the furnace body 3 as shown in FIG. Is formed.

The distal end of each gas introduction pipe 6 is inserted into the furnace tube 4, and the distal end of each gas introduction pipe 6 has a nozzle 7.
Are arranged. The nozzle 7 has a predetermined length.
As shown in FIG. 2, the core tube 4 is arranged along the inner peripheral surface. As shown in FIG. 3, a plurality of jet ports 7
a is formed, and each of the injection ports 7a is directed toward the axial center of the core tube 4 and is positioned with respect to the axial center of the core tube 4.
The opening is formed in a direction inclined at a predetermined angle in the circumferential direction. A compound gas flows into these gas introduction pipes 6, and the compound gas introduced into the gas introduction pipe 6 flows from an injection port 7 a of a nozzle 7 toward an axial center of the furnace tube 4 as shown by an arrow in FIG. 3. At the same time, and in the direction of swirling in the core tube 4.

Next, the operation of the present embodiment will be described. When a film is vapor-grown on a sample by the vapor-phase growth apparatus 1, the sample is placed on the boat 5 and stored in the central portion of the shaft in the core tube 4, and then the core tube 4 is sealed and formed. A compound gas containing the constituent elements of the thin film is supplied from the gas inlet tube 6 into the furnace core tube 4, and the sample on the boat 5 is heated by infrared rays or the like so that the sample is vapor-phase grown to produce a thin film.

At this time, the nozzle 7 provided at the tip of the gas introduction pipe 6 is disposed along the inner peripheral surface of the furnace tube 4 and the injection port 7a formed in the nozzle 7 is 4 is formed toward the axial center direction,
The compound gas injected from the nozzle 7 of the gas introduction pipe 6 into the furnace tube 4 is injected in the axial center direction of the furnace tube 4 as shown by an arrow in FIG.

Therefore, the compound gas injected from the nozzle 7 is uniformly diffused with respect to the sample on the boat 5 disposed at the center of the furnace tube 4, and the thickness and concentration of the impurity layer generated in the sample are reduced. It can be uniform.

The injection port 7a is formed so that the compound gas injected from the injection port 7a is directed toward the axial center of the furnace tube 4 and swirls inside the furnace tube 4. Therefore, the compound gas injected from the nozzle 7 is swirled in the furnace tube 4 and diffused more evenly with respect to the sample on the boat 5, so that the thickness and concentration of the impurity layer generated in the sample are more uniform. Can be

As described above, the invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to the above-described one, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

[0024]

According to the first aspect of the present invention, the nozzle at the tip of the gas introduction tube for introducing gas into the furnace tube is arranged along the inner peripheral surface of the furnace tube. Since the injection port is formed so as to open toward the axial center of the furnace tube, gas is injected from the nozzle outlet toward the axial center of the furnace tube, and the gas is injected into the sample stored in the furnace tube. It can be diffused uniformly, and the thickness and concentration of impurities formed in the sample can be made uniform.

According to the vapor phase growth apparatus of the present invention, the injection port is directed toward the axial center of the core tube.
Since it is formed in a direction inclined at a predetermined angle in the circumferential direction of the furnace tube with respect to the axis center, the gas is injected from the injection port of the nozzle toward the shaft center direction in the furnace tube, and the gas is swirled in the furnace tube. As a result, the gas can be more uniformly diffused into the sample housed in the furnace tube, and the thickness and concentration of impurities formed in the sample can be made more uniform.

According to the third aspect of the present invention, since a plurality of gas introduction pipes are provided, gas is injected from the nozzles of the plurality of gas introduction pipes in the axial center direction of the furnace tube. In addition, the gas can be more uniformly diffused into the sample housed in the furnace tube, and the thickness and concentration of impurities formed in the sample can be made more uniform.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a main part of a vapor phase growth apparatus to which an embodiment of a vapor phase growth apparatus of the present invention is applied.

FIG. 2 is a top view of a furnace body of the vapor phase growth apparatus of FIG.

FIG. 3 is a sectional view of the vicinity of a nozzle of the vapor phase growth apparatus of FIG. 1;

FIG. 4 is an enlarged front view of a nozzle portion of a gas introduction pipe of the vapor phase growth apparatus of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vapor growth apparatus 2 Cap 3 Furnace body 3a hole 4 Furnace tube 5 Boat 6 Gas introduction pipe 7 Nozzle 7a Spout

Claims (3)

[Claims] A furnace tube having a hollow tube shape in which a sample to be vapor-phase grown is stored, and a gas introduction tube having a tip inserted into the furnace tube and introducing a predetermined gas into the furnace tube. In the vapor phase growth apparatus provided, the gas introduction pipe has a nozzle formed with a predetermined number of injection ports arranged along an inner peripheral surface of the furnace core tube at a tip end inserted into the furnace core tube. Wherein the injection port is formed so as to open toward the axial center of the furnace tube. 2. The injection port is formed so as to extend toward the axial center of the core tube and to incline at a predetermined angle in the circumferential direction of the core tube with respect to the axial center. The vapor phase growth apparatus according to claim 1, wherein 3. The gas supply system according to claim 1, wherein a plurality of the gas introduction pipes are provided, and each of the gas introduction pipes has the nozzle at a tip end thereof. Phase growth equipment.