JPS6242516A - Organic metal thermal decomposition vapor growth device - Google Patents

Abstract

PURPOSE:To prevent ignition by a method wherein a supply opening for organic metal and As (compound) is provided under a susceptor so as to cover deposits containing P adhered on the inside wall of a reaction pipe with As (compound). CONSTITUTION:A substrate 12 is placed on a susceptor 13 rotating in a reaction pipe 11. A supply opening 27 for epitaxial growth is provided on an upper part of the susceptor 13, and a supply opening 28 for organic metal and As (compound) is provided on the lower side of the susceptor 13. A jig 26 is provided to prevent the gas in the downstream of the susceptor 13 from flowing reversely. Just before the growth by means of the gas supplied from the supply opening 27 is terminated, the gas is supplied from the supply opening 28 while the temperature of a heater 24 is held lower than that of the susceptor 13, and the supply of the gas from the supply opening 28 is continued after the termination of the growth. By doing this, P (compound) deposited on the place other than the substrate 12 is covered with As (compound), thereby preventing P from being ignited even if the reaction pipe is exposed to air.

Description

[Detailed Description of the Invention] [Summary] In a device in which flammable substances such as phosphorus are deposited and accumulated in the exhaust gas section of a gas phase treatment device, when the device is exposed to the atmosphere, the atmosphere and phosphorus come into direct contact. This is a device that utilizes the precipitation of arsenic (As) or an As compound to prevent this from occurring.

[Industrial application field]

The present invention relates to a metal organic pyrolytic vapor deposition (MO-CVD) apparatus, and more specifically, to an improvement of an MO-CVD apparatus for growing a compound semiconductor containing phosphorus.

[Conventional technology]

A conventionally used MO-CVD apparatus is shown in the cross-sectional view of FIG. 3, in which 11 is a reaction tube made of quartz;
2 is a base plate placed on a susceptor 13 rotating in the direction of the arrow, 14 is an RF coil (heater), 15 is an exhaust gas treatment device, 16.17.18.19.20 is TEiG, TE
In.

DEZn, t'l13, and Ast13 gas cylinders, and 21 indicate mass flow controllers (MFC), respectively. These gas phase reaction gases are appropriately controlled by the MFC 21 and sent to the reaction chamber 11, and a desired compound semiconductor is deposited on the substrate 12 while being heated by the RF coil 14.

[Problem that the invention seeks to solve]

In the conventional apparatus described above, residual components of the gas phase reaction gas are deposited on areas other than the substrate 12, that is, on the inner wall of the reaction tube around the susceptor 13, the manifold, the exhaust gas pipe, etc. If this attached substance contains phosphorus,
There is a risk of ignition if the reaction tube is exposed to an oxygen-containing atmosphere (atmosphere), and great care must be taken when opening the reaction tube. Furthermore, phosphorus compounds adhering to the susceptor evaporate when heated, causing deterioration of the properties of the epitaxial crystal. Furthermore, after the phosphorus is burned, P2175 and phosphoric acid are adsorbed onto the inner wall of the reaction tube, contaminating the inner wall.

The present invention was created in view of these points, and is an MO that does not cause phosphorus ignition when the reaction tube is opened to the atmosphere.
- The purpose is to provide a CVD device.

[Means for solving problems] FIG. 1 is a sectional view of an embodiment of the present invention.

What about the compound semiconductor containing phosphorus in Figure 1? In the device for 10-C Siυ, in addition to supplying gases such as organometallic and group II element hydrogen compounds from the upstream part of the high-frequency induction heating susceptor 13, organometallic or arsine gas, or arsine gas is supplied from the downstream part of the susceptor 13. and an organometallic gas.

[Effect]

In the above device, phosphorus attached to parts other than the substrate,
A device that covers phosphorus-containing precipitates with As-containing precipitates to prevent precipitates that are easily oxidized, such as phosphorus compounds, from coming into direct contact with the atmosphere when the reaction tube is exposed to the atmosphere. are provided, and the phosphorus compounds and phosphorus deposited and accumulated in the upstream and downstream parts of the susceptor are covered with As compounds and As precipitates. For this purpose, in addition to the gas supply port for the purpose of epitaxial growth on the substrate, a gas supply port for depositing As and As compounds is provided, and furthermore, a heating means is provided to promote the precipitation of As and As compounds. It is provided somewhere other than the susceptor.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a cross-sectional view of the MO-CVD apparatus according to the present invention.
2 is a TMG gas cylinder. Conventional M shown in Figure 3
The difference from O-CVD equipment is As) I 3 and TM
G supply line 23 and RF heating the SASSEF 13
In addition to the coil 14, there is an electric resistance heater 24, and a jig 2 that prevents the gas downstream of the susceptor from flowing back toward the substrate.
6 is provided. In addition, in Figure 1,
25 is a power source for the heater 24.

When growing InP, a gas containing As113 and TMG is supplied from the line 23 and the second gas supply port 28 from about 20 minutes before the end of InP growth.The growth gas is supplied from the first gas as before. (supplied from the port 27), so as not to affect the temperature of the heater 24 on the substrate 12.
Maintain the temperature at 50°C to 100°C lower than the temperature of the susceptor 13,
This will prevent gas convection (flow in one direction).

When the growth of InP is stopped, the supply of TMG and ASH3 is continued for about 20 minutes after the supply of TEIn and PH3 is stopped. By carrying out such treatment, phosphorus and phosphorus compounds deposited on areas other than the substrate 12 are diluted with As and Ga, and further covered with As and Ga-As.

FIG. 2 shows a modification of the susceptor 13 in FIG. 1, which has a double structure in which a second susceptor 13a is added to the original susceptor 13, and a backflow prevention partition plate 26a is arranged between the susceptor 13 and the second susceptor 13a. and allow the reaction gas to flow as shown by the arrow.

By using the MO-CVD apparatus described above, when the susceptor and jigs are exposed to the atmosphere for taking out the substrate and cleaning various jigs after epitaxial growth on the substrate,
Phosphorous ignition is prevented and health and safety are improved.

Phosphorus is not only flammable but also harmful in itself, but by covering it with As, which is toxic but inactive and easy to handle, the conventional problems encountered with phosphorus have been solved.

〔Effect of the invention〕

As described above, according to the present invention, the ignition of accumulated phosphorus and phosphorus compounds is prevented and safety is increased;
This has the effect of reducing the emission of phosphorus vapor from the accumulation of phosphorus and phosphorus compounds, and reducing the deterioration of characteristics at the substrate/epitaxial layer interface.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a sectional view of a modification of the susceptor shown in FIG. 1, and FIG. 3 is a sectional view of a conventional MO-CVD apparatus. 1 to 3, 11 is a reaction tube, 12 is a substrate, 13 is a susceptor, 13a is a second susceptor, 14 is an RF coil, 15 is an exhaust gas treatment device, 16 is a TEG gas cylinder, 17 is a TEIn gas cylinder, 18 is a DEZn gas cylinder, 19 is a PH3 gas cylinder, 20 is a sH3 gas cylinder, and 21 is an MFC. 22 is a TMG gas cylinder, 23 is a supply line for AsH3 and TMG gas, 24 is a heater, 25 is a power supply, 26 is a gas backflow prevention jig, 26a is a gas backflow prevention partition plate, 27 is a first gas supply port, 28 is a first gas supply port 2 gas supply ports.

Claims (2)

[Claims] (1) In an apparatus for growing a compound semiconductor containing phosphorus, a first gas supply port (27) for supplying growth gas is provided above the high-frequency induction heating type susceptor (13, 13a), and the susceptor (13, 13a) An organometallic pyrolysis vapor phase growth apparatus characterized in that a second gas supply port (28) for supplying an organometal and arsenic or an arsenic compound is provided below. (2) Heater (24) that heats the lower part of the susceptor (13)
) The organometallic pyrolysis vapor phase growth apparatus according to claim 1, further comprising: