JPS6261319A - Vapor growth device - Google Patents

Abstract

PURPOSE:To form a thin film crystal with high evenness by reducing the movement and vibration of a crystalline substrate by a method wherein a fixing jig made of a material with a larger thermal expansion coefficient than those of a crystalline substrate and a graphite supporting base is provided between the crystalline substrate and the graphite supporting base. CONSTITUTION:A large copper-made fixing ring 15 with a larger thermal expansion coefficient than those of a graphite supporting base 13 and a crystalline substrate 14 as well as the crystalline substrate 14 are arranged on a fixing ring supporting base 12 from a crystalline substrate inlet and outlet 11 to be inserted into a cylindrical hole provided below the graphite supporting base 13 by a vertically driving mechanism 16. Next the fixing ring 15 is thermal- expanded by heating the inside of a reaction tube 8 using heating coils 7 to fix the crystalline substrate 14 and the graphite supporting base 13. Later the fixing ring supporting base 12 is lowered and the graphite supporting base 13 is turned by a turning mechanism 9 while a material gas is fed from a material gas inlet 10 and exhausted from a gas outlet 11 to form a compound thin film on the surface of crystalline substrate 14.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a vapor phase growth apparatus used for manufacturing semiconductors.

[Technical background of the invention and its problems]

The method of manufacturing thin film crystals by vapor phase growth is considered indispensable for compound semiconductor device processes because it allows the production of crystals with complex compositions and layered structures.

A conventional vapor phase growth apparatus is shown in all 43 diagrams.

A crystal substrate 4 is placed on a graphite support 3 in a quartz reaction tube 8.
Place the heating coil 7; (preheat to 700 to 800°C.) Into the quartz reaction tube 8, from the raw material gas inlet 10, trimethylgallium and arsine, and trimethylaluminum and arsine alternately. By introducing this, a compound W1 having a complex composition and structure is formed on the substrate.In the conventional example, the crystal substrate is simply placed on the graphite support 3; Because the di-crystalline substrate moves or vibrates during rotation or due to vibrations from other sources, the uniformity of the thin film crystal is impaired.

Since the substrate is not fixed, the direction in which the substrate can be installed is limited to upwards, which poses problems such as the possibility that carbon generated during the reaction tends to contaminate the substrate.

[Purpose of the invention]

The object of the present invention is to provide an entire vapor phase growth apparatus which improves the above-mentioned drawbacks of the conventional apparatus, improves the uniformity of thin film crystals, and reduces carbon contamination on the substrate.

[Summary of the invention]

The vapor phase growth apparatus of the present invention has a structure in which the crystal substrate and the graphite support plate are fixed using a fixing jig made of a material having a coefficient of thermal expansion larger than that of the crystal substrate and the graphite support plate.

〔Effect of the invention〕

The present invention reduces movement and vibration of the crystal substrate.

Obtain thin film crystals with high uniformity. Furthermore, by fixing the board, the board can be mounted in any direction. When installed facing downward, carbon contamination of the substrate generated during one reaction f:? $,
It is possible to reduce the

[Embodiments of the invention]

A cross-sectional view of an embodiment of the present invention is shown in FIG. 1. A ring support 12 for fixing from the dry crystal substrate inlet/outlet 11 is made of steel having a larger thermal expansion coefficient than that of the graphite support 13 and the crystal substrate 14. The fixing ring 15 and the crystal substrate 14 are all set, and the 5 m crystal substrate 14 is moved to the fixing ring 15 by the vertical drive mechanism 16.
The graphite support 13 is then lifted up and placed into a cylindrical hole provided toward the bottom of the graphite support 13. The fixing ring 15 is supported in the same position as the fixing ring support stand 12, and the heating coil 7 is placed in a tentative state.
When the inside of the reaction tube 8 is heated, the fixing ring 15 made of copper, which has a large coefficient of thermal expansion, thermally expands and presses the inner surface of the cylindrical hole of the graphite support 13 and the cylindrical portion of the crystal substrate 140 from the side. As a result, the crystal substrate 14 and the graphite support base 13 are fixed. Then fixed/
The graphite support 12 is lowered, and while the graphite support 13 is rotated by the one-rotation mechanism 9, the raw material gas is introduced from the raw gas inlet 10, and while being exhausted from the gas outlet 11, a thin film of the compound is formed on the surface of the crystal substrate 14. .

Details of the crystal substrate mounting part in this embodiment All 9 shown in FIG. Set it on the table. Furthermore, a groove corresponding to the protrusion on the upper part of the fixing ring support 12 is provided in the lower part of the fixing ring 15, so that it can be set in one position.

The material of the fixing jig provided between the crystal substrate and the graphite support is not limited to copper, but also includes other metal alloys, ceramics, and fibers.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the present invention, FIG. 2 is a sectional view showing details of the main parts of the invention, and FIG. 3 is a sectional view of a conventional device. 13...Graphite support stand 14...Crystal substrate 14...Fixing ring Agent Patent attorney Nori Chika Yudo Kikuo Takehana Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a vapor phase growth apparatus that grows a thin film on a crystal substrate,
A vapor phase growth apparatus characterized in that a fixing jig made of a material having a larger coefficient of thermal expansion than the crystal substrate and the graphite support is provided between the crystal substrate and the graphite support.