JPS60235796A - Device for gaseous phase growth and method of gaseous phase growth - Google Patents

Abstract

PURPOSE:To prevent bad influence on crystal growth caused by an attached reaction product and to obtain a high-quality crystal continuously, by applying a covering material to a high-temperature material to keep a substrate at a growth temperature. CONSTITUTION:The covering material 12 free from adhesion of a reaction product is attached to the high-temperature material 11, and the substrate 4 is placed on the covering material 12. The high-temperature material 11 is heated by the high-frequency heater 6, the substrate 4 is kept at a growth temperature (for example, 550 deg.C in the case of three-dimensional mixed crystal of InGaAs), raw material gases are introduced into the reaction furnace 2 by the gas inlet pipes 1 and 3, respectively, to form a growth layer. After growth is over, the grown substrate 4 and the covering material 12 to which the reaction product is bonded are moved, and the high-temperature material 11 is dirctly kept at the original temperature. Consequently, bad influence on the crystal growth caused by the attached reaction product can be prevented, improved crystal growth can be continuously carried out, high-quality crystal having improved crystallizability can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a vapor phase growth apparatus and a growth K/J method capable of obtaining a high quality and uniform growth layer.

Conventional Structures and Problems There is a vapor phase growth method using thermal decomposition of raw material gas as a technique for vertically growing a 1' conductor crystal necessary for manufacturing a conductor device. For example, the vapor phase growth of Sl using SiH4 (monon la/), υ, and the organometallic vapor phase growth η, (M0CVDθ,) of growing a compound ``I'' conductor crystal using a metal (alkylated), It is without.

In these vapor phase growth apparatuses, the holding table on which the substrate is placed is generally heated (7) to the growth temperature (1), and the raw Fl gas is Minute M
Crystals grow around IXJ.

However, since the surface of the holding table for the raw material gas (RI) is also heated, the entire thermal decomposition reaction is naturally evaporated.Therefore, the thermally decomposed substances of the raw material gas and other chemical substances adhere to this holding table as well. (2) It's too late. In general, graphite is used for production and growth, so the IK compound gets inside the holder. For this reason, it may stick to or get into the holder during the next crystal growth. There was a problem that some of the reactants in the process were generated as gas again, which adversely affected the quality of the grown layer.

As an example 2, InP substrate is coated with InP by MOCVD method.
The growth of GaAs-, r-element mixed crystal will now be described. Figure 1 is a structural diagram of the reactor section of a typical MOCVD device.
/ Jesu. As the thickness of In and Ga which are Group ■ elements, triethylindium ((C2H
s)3In).

Triethyl gallium ((C2H5)3") is used and is supplied to the reactor 2 through an inlet pipe 1 together with a carrier gas (hydrogen as L). On the other hand, arunone (AsH3) is used as a raw material for As, a group V element. is used, and is supplied to the reactor 2 from the inlet pipe 3. The raw material undergoes thermal decomposition reaction A
SH3(-X(C2Hs)3G&+(1-x)(C,,
H5) 3In-+In, -xGaxAs 13G,,H
6, and put In, 4G&X As (X=
0.47) grows. Note that 6 is a high frequency coil. The exhaust gas after the reaction exits from the υ1 trachea 7. It's Kade.
Since the substrate 4 is InP, phosph (/(PH3)) is supplied to the reactor 2 from the inlet tube 3 until the start of growth in order to prevent dissociation of P at the temperature of the layer.

However, since the holding table 5 is also heated, the original t(1/1/
chemical substances (As, Ga, In, In, -xGaxAs
) is attached. Then, when the temperature is increased for the next growth, the holding table 5
From this, the attached G& is generated again as steam gas,
A phenomenon was observed in which GaP grew on the InP substrate by a reaction with PH3, which was supplied to prevent the dissociation of P. In addition, due to gas deposits generated from the holding table 6 in the crystal member, the supply ratio of the raw materials being supplied is shifted.
In order to worsen the crystallinity of the grown layer and modify the points after 150, after the crystal growth Pr, -L gas is supplied to the IX reaction furnace 2 and heated, and the holding table 5 is cleaned. There is a law. However, since etch gas is used, it damages the gas piping system and makes continuous growth impossible.

Purpose of the Invention The present invention provides a method for preventing or reducing the adhesion of reactants to the high-temperature body by covering a part or the whole of the high-temperature body with a substrate to keep the substrate at the growth temperature. The purpose is to prevent the reactants generated near the substrate from emitting gas again and hindering good crystal growth (.zeta.), thereby improving the quality of the raw conductor crystal growth layer.

Still, it is an object of the present invention to enable continuous growth by replacing the coating after each growth.

Structure of the Invention The present invention is characterized by the following features:
! It is a vapor phase growth apparatus comprising an Il'1 body, a covering body that covers the whole or a part of this high-temperature body and on which a plate can be placed.In this case, the covering body),
(In board part 191) There may be a hole in the same shape as the board so that the top board can be directly heated from the high Il conductor.

Further, the present invention provides a vapor phase growth apparatus as described below.
1. Attach a coating to the high-temperature body without adhesion of reactants. Next, place the plate on the coating and heat it at the growth temperature to form a growth layer. And, after growth, Fi from the 17111 body with the reactant attached.

This is a vapor phase growth method that includes a step of slicing.

Description of examples An embodiment of the present invention will be described in detail based on the drawings.

FIG. 2 is a schematic structural diagram of a reactor section of a vapor phase growth apparatus incorporating an embodiment of the present invention. Note that, for ease of explanation, structural features common to the conventional example are numbered the same as in FIG. 1.

The same U as the conventional example (I was applied to the InP substrate j by MOCVD method)
When growing a ternary mixture of n GaAs, introduction efficiency・1
'C mo-te Ill fi! 1. ．． 5L element (In,
Ga) No IQN Thealt'J Ni 1 Ruin/Um, triethylpotassium or carrier gas (hydrogen at 1-8)
At the same time, supply to the reactor 2 is also introduced 17).
3 and Al/No, which is the source t) of Group V element (As), is supplied. ((Reverse 4, the gas upstream side of the graphite high fllf body 11, which is being high-frequency heated by the high-frequency wave heater 6, is placed on the J-made sheathing body 12, and the sheathing body 12 The growth temperature is maintained by the heat of the high-temperature body 11 via the substrate.Therefore, the raw material supplied to the substrate 2 undergoes thermal decomposition reaction on the substrate surface and becomes InG.
aAs ternary mixed crystal grows. 12 coverings in the same prefecture as Sone
The reactants of the raw materials also adhere to the exposed surface of the high-temperature body 11 that is not covered by the coating 12 on the downstream side of the gas. However, by replacing the coating 12 after the growth is completed, the attached reactants can be removed. It's 1.
Since the reactants attached to the exposed surface of the high temperature body 11 are on the downstream side of the gas flow, even if they are generated as a gas,
There is no effect on the board surface. Therefore, in view of the above, the crystal growth method is as follows.

First, the coating 12 free from adhesion of reactants is attached to the high-temperature body 11, and then the J-mount plate 4 is placed on the coating 12. Next, the high-temperature body 11 is heated by the high-frequency heating device 6 to maintain the substrate 4 at the growth temperature (550″C in the case of InGaAs ternary mixed crystal).
Raw material gases are introduced into the reactor 2 through gas introduction pipes 1 and 3, respectively, to form a growth layer. After the growth, the grown substrate 4. and the coating to which the reactants have adhered are removed, and the high-temperature body 1
Keep 1 in its original state of 11.

In this way, it is possible to prevent adverse effects on crystal growth due to the attached reactants, so that good crystal growth can always be carried out continuously, and high quality crystals with good crystallinity can be obtained.

1, the substrate 4 is moved in and out of the reactor 2 by moving only the cover 12 while it is placed on the cover 12, and the high-temperature body 11 is fixed. Furthermore, if a gas exchange chamber, which is well known as a vapor phase growth apparatus, is provided, and gas is introduced and removed therein, the high-temperature body 11 does not come into contact with air, that is, oxygen. Therefore, the compound by MOC-iD method ゛)'
Deterioration of crystallinity due to oxygen contamination during conductor growth can be prevented.

Note that the u1 gas after fy is exhausted through the exhaust pipe 7.

FIG. 3 is a schematic structural diagram of a reactor in which the coating 12 covers the metal body of the high-temperature body 11. In this case, the covering 12 can be separated into two parts in order to replace the covering 12.

FIG. 4 is a schematic structural diagram of a reactor section of a vapor phase growth apparatus showing another embodiment of the present invention. The difference from the embodiment shown in FIG. 2 is that a hole 13 having the same shape as the base &4 is made in the substrate mounting portion of the cover 12. In other words, the substrate 4 is fitted into the hole 13 of the base &4. The high temperature body 11 is heated directly by the body 11 and maintained at a temperature of 11 degrees.Furthermore, the high temperature body 11 is heated by the substrate 4 and the covering body 12.
Since the upstream side of the gas flow is covered [71], adhesion of reactants can be prevented.

In addition, although the explanation in this section has mainly been limited to the MOCVD method, as stated at the beginning, the present invention is suitable for vapor phase growth methods that utilize thermal decomposition of raw material gas. can.

Effects of the Invention The vapor phase growth apparatus of the present invention is equipped with a high-temperature body for keeping the substrate at growth humidity and a covering body on which the substrate can be placed while covering all or part of the high-temperature body. During growth, it is possible to prevent the reaction products of the attached raw materials from being generated as +JG gas and inhibiting crystal growth, and as a result, high quality crystals can be obtained.

1. By replacing the coating, cleaning with etching gas becomes unnecessary, allowing continuous growth, which has a great practical effect.

[Brief explanation of the drawing]

Fig. 1 is a schematic cross-sectional view of the reactor of a general MOCVD equipment, Fig. 2 is a schematic cross-sectional view of the reactor of an MOCVD equipment according to an embodiment of the present invention, and Fig. 3 is a high-temperature body with a coating. FIG. 4 is a schematic cross-sectional view of the reactor structure when the entire reactor is covered. FIG. 4 is a schematic cross-sectional view of the reactor of the MOCVD apparatus which is an embodiment of the present invention. 4 substrate, 11 high temperature body, 12 covering body, 13 hole with the same shape as the substrate. Name of agent: Patent attorney Toshio Nakao (1 or 11.-).

Claims (3)

[Claims] (1) A high-temperature body for keeping the human plate at the growth temperature; A vapor phase growth apparatus characterized by comprising a covering body that covers the whole structure and a part of the A body, is detachable, and on which the substrate can be placed. (2) A gas phase according to claim 1, characterized in that a hole having the same shape as the substrate is formed in the J plate device part of the covering body so that the substrate is directly heated by the high temperature body. growth equipment. (3) When performing vapor phase growth using the thermal decomposition reaction of raw material gas, the culm is attached to the high-temperature body, and then the substrate is placed on the coating and the growth temperature - soil is applied. 1. A vapor phase growth method comprising a step of heating to form a layer, and a step of removing the coating from the high-temperature body after the growth.