Silicon carbide single crystal manufacturing apparatus

Patent metadata

Field	Value
Publication number	US-9644286-B2
Application number	US-201214126520-A
Country	US
Kind code	B2
Filing date	Jul 24, 2012
Priority date	Jul 28, 2011
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A silicon carbide single crystal manufacturing apparatus includes a vacuum chamber, a pedestal on which a seed crystal is disposed, an inlet of source gas, a reaction chamber extending from a bottom surface of the vacuum chamber toward the pedestal, a first heating device disposed around an outer periphery of the reaction chamber, a second heating device disposed around an outer periphery of the pedestal, and an outlet disposed outside the first and second heating devices in the vacuum chamber. After the source gas supplied from the reaction chamber is supplied toward the pedestal, the source gas is let flow outward in a radial direction of the silicon carbide single crystal between the reaction chamber and the silicon carbide single crystal and is discharged through the outlet.

First claim

The invention claimed is:

1. A silicon carbide single crystal manufacturing apparatus comprising:
a vacuum chamber;
a pedestal on which a seed crystal made of a silicon carbide single crystal substrate is disposed, the pedestal disposed in the vacuum chamber;
an inlet disposed on a bottom surface of the vacuum chamber and introducing source gas of silicon carbide from below the seed crystal;
a reaction chamber extending from the bottom surface of the vacuum chamber toward the pedestal in the vacuum chamber, the reaction chamber including a cylindrical member having a hollow portion through which the source gas passes, the reaction chamber decomposing the source gas by heating and supplying the decomposed source gas toward the seed crystal;
a first heating device disposed around an outer periphery of the reaction chamber and heating the reaction chamber;
a second heating device disposed around an outer periphery of the pedestal and keeping a high temperature of a growth surface of a silicon carbide single crystal grown on a surface of the seed crystal;
an outlet disposed outside the first and second heating devices in the vacuum chamber and discharging unreacted gas in the source gas; and
a guide surrounding the pedestal, disposed at a predetermined distance apart from the pedestal, and disposed at a predetermined distance apart from an upper end of the reaction chamber adjacent to the pedestal, wherein:
the second heating device is disposed around an outer periphery of the guide,
an end portion of the reaction chamber adjacent to the pedestal has a flange shape,
an end portion of the guide adjacent to the reaction chamber has a flange shape,
the upper end of the reaction chamber is located below the growth surface of the silicon carbide single crystal with a clearance, and
after the source gas supplied from the reaction chamber is supplied toward the pedestal, the source gas is let flow outward in a radial direction of the silicon carbide single crystal through the clearance between the upper end of the reaction chamber and the growth surface of the silicon carbide single crystal and a clearance between the reaction chamber and the guide, is let flow outside the first and second heating devices in the vacuum chamber, and is discharged through the outlet.

2. The silicon carbide single crystal manufacturing apparatus according to claim 1 ,
wherein purge gas is introduced through a clearance between the pedestal and the guide, and is let flow outside the first and second heating devices in the reaction chamber through the clearance between the reaction chamber and the guide while diluting the source gas.

3. The silicon carbide single crystal manufacturing apparatus according to claim 1 , further comprising
a pull-up mechanism pulling up the pedestal,
wherein an inside diameter of the guide increases upward.

4. The silicon carbide single crystal manufacturing apparatus according to claim 1 ,
wherein the reaction chamber and the pedestal are coaxially disposed, and
wherein an outside diameter of the pedestal is equal to or greater than an inside diameter of an end of the reaction chamber adjacent to the pedestal.

5. The silicon carbide single crystal manufacturing apparatus according to claim 1 ,
wherein the first and second heating devices include induction heating coils and corrosion-resistant structures covering the induction heating coils.

6. The silicon carbide single crystal manufacturing apparatus according to claim 1 ,
wherein purge gas is introduced from the bottom surface of the vacuum chamber and is let flow outside the first and second heating devices in the vacuum chamber while diluting the source gas.

7. The silicon carbide single crystal manufacturing apparatus according to claim 1 , further comprising
a shielding plate disposed in the vacuum chamber, the shielding plate covering a position corresponding to a portion between the reaction chamber and the silicon carbide single crystal through which the source gas is discharged.

Assignees

• Hara Kazukuni
• Denso Corp

Inventors

• Hara Kazukuni

Classifications

• C30B25/10 Primary

  Heating of the reaction chamber or the substrate · CPC title

• C30B25/08 Primary

  Reaction chambers; Selection of materials therefor · CPC title

• C30B25/12

  Substrate holders or susceptors · CPC title

• C30B25/14

  Feed and outlet means for the gases; Modifying the flow of the reactive gases · CPC title

• C30B29/36

  Carbides · CPC title