JPS6221231A - Vapor-phase growing device - Google Patents

Abstract

PURPOSE:To control easily and rapidly the feed amount of substance to be fed in a non-gaseous state by a method wherein the non-gaseous deposited substance feeding unit is provided with an additional heating means. CONSTITUTION:Reaction gas heating means 2 are provided on the outer side of a reaction tube 1 made of quartz and so forth, and a susceptor 3 which supports a wafer 5, a non-gaseous deposited substance feeding unit 4 (an example: an mercury reservoir) and the additional heating means 7 of the unit 4 is provided on the outer side of the tube 1. The feed amount of the non-gaseous deposited substance to be fed from the unit 4 can be controlled in a capacity and rapidly by the means 7. Moreover, as the susceptor 3 is formed of a conductive substance and alternating magnetic flux sources 8 for induction heating are provided in the vicinity of the susceptor 3, the temperature of the susceptor 3 can be controlled independently. Accordingly, the temperatures of the wall surface of the tube 1, the unit 4 and the susceptor 3 can be controlled independently.

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] This is a vapor phase growth apparatus suitable for vapor phase growth in which a substance with a high vapor pressure such as Hg is supplied in a non-gaseous state.

An additional heating means is provided in the supply device for a substance with a high vapor pressure such as Hg that is supplied in a non-gaseous state, and the amount of the substance with a high vapor pressure such as Hg that is supplied in a non-gaseous state can be easily and quickly controlled. It was designed so that it could be done. Furthermore, the susceptor that supports the wafer is made of a conductive material, and an alternating magnetic flux source for induction heating such as a high-frequency coil is installed in the vicinity of the susceptor, so that the temperature of the susceptor can be controlled quickly and independently from the temperature of other regions. It is something.

[Industrial application field]

The present invention relates to a vapor phase growth apparatus. In particular, compound semiconductors that have high vapor pressure substances such as Hg as one of their constituents, such as H
The present invention relates to a vapor phase growth apparatus suitable for carrying out a gas growth method such as a metal organic CVD method, in which a substance with a high vapor pressure such as Hg is supplied in a non-gaseous state in order to grow materials such as Hg, lCdxTe, etc. in a vapor phase.

[Conventional technology]

An example of a vapor phase growth apparatus according to the prior art is shown in FIG. 13 are provided.

2 is a reaction tube heating means, which is generally a resistance heating device, a high frequency induction heating device, or the like. A susceptor 3 supports the wafer/\5 and is made of graphite, quartz, or the like. 4 is a non-gaseous deposited substance (liquid substance) supply device, which is a container for supplying, for example, Hg or the like.

[Problem that the invention seeks to solve]

As can be described, in the conventional vapor phase growth apparatus, a single heater is used as a means for heating one reaction tube, and a desired region of one reaction tube can be controlled to an arbitrary temperature. Especially not.

The wall temperature, the wafer temperature (susceptor temperature),
The temperature of the Hg reservoir (non-gaseous deposited material supply device) is not controlled independently.

By the way, compound semiconductors that have high vapor pressure substances such as Hg as one of their constituents, such as Hg 1-, Cd, T e
When vapor phase growth is performed, it is desirable to keep the temperature of the wafer relatively high, for example, about 350 to 450°C.

On the other hand, it is desirable to maintain the temperature of the I (g reservoir (non-gaseous deposition material supply device) at a relatively low level, for example, around 230 to 320 degrees Celsius, and the temperature of the wall surface is equal to the temperature of the wafer and Hg
It is desirable to maintain a temperature intermediate to that of the reservoir (non-gaseous deposition material supply device); this temperature is most important, since the composition of the deposited semiconductor is determined by the wafer temperature, and the temperature of the wall surface is high. Deposition occurs on this surface, which is uneconomical, and if the temperature of the wall surface is low, the vapor pressure, especially Hg vapor pressure, deviates from the desired value and the composition of the deposit becomes an undesired value.
This is because if the temperature of the ag reservoir (non-gaseous deposited material supply device) is high, the Hg vapor pressure will rise too much.

In short, when growing a compound semiconductor such as Hg1-, CD, Te, etc., in a vapor phase, which has a high vapor pressure substance such as Hg as one of its constituents, the temperature of the wall surface, the temperature of the wafer (temperature of the susceptor), It is desirable to be able to control the temperature of the Ig reservoir (non-gaseous deposition material supply device) independently.

In response to this demand, an object of the present invention is to provide a vapor phase growth apparatus suitable for vapor phase growth when a part of the deposited material contains a substance with a high vapor pressure, such as Hg, and is supplied in a non-gaseous state. In particular, it is an object of the present invention to provide a vapor phase growth apparatus suitable for metal organic CVD methods such as Hg1□Cd□Te. [Means for Solving the Problems] The means taken by the present invention to achieve the above object are as follows: a reaction tube 1, a reaction tube heating means 2, a susceptor 3 for supporting a wafer, and a non-gaseous deposited substance. The present invention consists in that an additional heating means 7 is added to the non-gaseous deposition material supply device 4 of the vapor phase growth apparatus having the supply device 4.

Furthermore, the susceptor 3 is made of a conductive material such as graphite, and an alternating magnetic flux source 8 for induction heating is provided near the susceptor 3.
It is even more effective if .

[Effect]

When performing vapor phase growth of a compound semiconductor such as Hg1□CdxDx, which has a high vapor pressure substance such as Hg as one of its constituents, the temperature of the wall surface, the temperature of the wafer (temperature of the susceptor), and the Hg reservoir (non- As mentioned above, it is desirable to control the temperature of the gaseous deposition material supply device independently.

When the high vapor pressure substance is supplied in a non-gaseous state, in order to meet the above requirements, an additional heating means is provided in the Hg reservoir (non-gaseous deposited material supply device), and the temperature of the Hg reservoir is adjusted to the temperature of the wall surface. It is easiest to control the temperature independently of the temperature, and it is also possible to control the temperature quickly, which is desirable from the standpoint of improving responsiveness. It is advantageous to use an induction heating method using a high frequency magnetic flux source so that the temperature of the wafer can be controlled independently of the temperature of the wall surface.

〔Example〕

Hereinafter, a vapor phase growth apparatus according to an embodiment of the present invention will be further described with reference to the drawings.

Referring to FIG. 1, a reaction tube 1 is made of quartz or the like, and is provided with a gas inlet 11, a gas outlet 12, and a wafer loading/unloading device 713. 2 is a reaction tube heating means, which in this example is of a resistance heating type. 3 is a susceptor that supports the wafer 5, and in this example,
It is made of graphite to make it conductive. 4 is a non-gaseous deposited material (liquid material) supply device, which in this example is an Hg reservoir. 7 is an additional heating means according to the gist of the invention, which in this example is a resistance heating device.

8 is an alternating magnetic flux source for induction heating according to an embodiment of the present invention, which is a high frequency coil in this example.

Using a vapor phase growth apparatus having the above structure, CdTe
In order to form a Hg1□CdxTe layer on the substrate, a GdTe substrate 5 is placed on the susceptor 3, and a gas inlet 1 is placed on the susceptor 3.
While supplying Cd and Te in gaseous form (in the form of methylated cadmium and ethylated cadmium) from 1 to 1 at a flow rate of 1 to 50 l/sec, the reaction tube heating means 2, additional heating means 7, and an alternating box for induction heating are supplied. While using it together with the magnetic flux source 8, a non-gaseous deposited substance (liquid substance) supply device (Hg reservoir)
4, the temperature of the reaction tube wall surface, and the temperature of the CdTe substrate 5 are independently controlled. Then, the temperature of the non-gaseous deposited substance (liquid substance) supply device (Hg reservoir) 4 is set to 230 to 320°C.
The temperature of the wall surface of the reaction tube was 350 to 450°C, and Cd
The temperature of the Te substrate 5 is set at an intermediate temperature.

As a result, undesirable deposits on the walls are prevented (
Desired set on CdTe substrate 5! (X value) of Hg,,C
d, Te layer is deposited.

〔Effect of the invention〕

As explained above, in the vapor phase growth apparatus according to the present invention, since the non-gaseous deposited material supplying device is provided with an additional heating means, the temperature of the non-gaseous deposited material supplying device and the temperature of the reaction tube wall surface are and the temperature of the susceptor can be controlled independently. Therefore, compound semiconductors that have high vapor pressure substances such as Hg as one of their constituents, such as Hg,
-, H for the purpose of vapor phase growth of CdxTe, etc.
, is suitable for implementation of a gas growth method such as a metal organic CVD method in which a substance with an equal high vapor pressure is supplied in a non-gaseous state. Furthermore, in the vapor phase growth apparatus according to the embodiment of the present invention, the temperature of the susceptor can also be controlled, so that the above-mentioned effects are further improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a vapor phase growth apparatus according to an embodiment of the present invention. FIG. 2 is a configuration diagram of a vapor phase growth apparatus according to the prior art. l...Reaction tube, 11-...Gas inlet, 12-Shell...
Gas outlet, 13. 1111 Wafer loading/unloading device, 2. Reaction tube heating means, 3. Susceptor,
4. Non-gaseous deposited material supply device, 5. φ heating device, 7. Additional heating means, 8. Alternating magnetic flux source for induction heating. 1. Agent Patent Attorney Sada Igeta -'1 Te, C2 layer. -Bino-・ノ'

Claims (1)

[Scope of Claims] [1] A reaction tube (1); a reaction tube heating means (2) provided surrounding the reaction tube (1) for heating the reaction tube (1); ), and a non-gaseous deposited material supply device (4), wherein the non-gaseous deposited material supply device (4) is provided with additional heating. A vapor phase growth apparatus characterized by comprising means (7). [2] The susceptor (3) is made of a conductive material, and an alternating magnetic flux source (8) for induction heating is provided near the susceptor (3). The vapor phase growth apparatus described.