SiC single crystal sublimation growth apparatus

Patent metadata

Field	Value
Publication number	US-11149359-B2
Application number	US-201916368977-A
Country	US
Kind code	B2
Filing date	Mar 29, 2019
Priority date	Mar 26, 2009
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

A physical vapor transport growth system includes a growth chamber charged with SiC source material and a SiC seed crystal in spaced relation and an envelope that is at least partially gas-permeable disposed in the growth chamber. The envelope separates the growth chamber into a source compartment that includes the SiC source material and a crystallization compartment that includes the SiC seed crystal. The envelope is formed of a material that is reactive to vapor generated during sublimation growth of a SiC single crystal on the SiC seed crystal in the crystallization compartment to produce C-bearing vapor that acts as an additional source of C during the growth of the SiC single crystal on the SiC seed crystal.

First claim

The invention claimed is:

1. A physical vapor transport growth system comprising:
a growth chamber charged with SiC source material and a SiC seed crystal in spaced relation; and
an envelope that is at least partially gas-permeable disposed in the growth chamber and separating the growth chamber into a source compartment that includes the SiC source material and a crystallization compartment that includes the SiC seed crystal, said gas-permeable envelope formed of a material that is reactive to vapor generated by sublimation growth of a SiC single crystal on the SiC seed crystal in the crystallization compartment, wherein said gas-permeable envelope is positioned in the growth chamber such that the vapor generated by sublimation growth reacts with the material forming the envelope to produce a carbon-bearing vapor that acts as an additional source of carbon during the growth of the SiC single crystal on the SiC seed crystal;
wherein the envelope is comprised of: a sleeve that surrounds sides of the SiC seed crystal and the growing SiC single crystal; and a gas-permeable membrane disposed between the SiC source material and a surface of the SiC seed crystal that faces the SiC source material;
wherein the gas-permeable membrane is made of porous graphite having a density between 0.6 and 1.4 g/cm 3 and a porosity between 30% and 70%;
wherein the graphite forming the gas-permeable membrane is comprised of graphite grains, each of which has a maximum dimension between 100 and 500 microns; and
wherein the gas-permeable membrane is disposed between 15 mm and 35 mm from the surface of the SiC seed crystal that faces the SiC source material.

2. The system of claim 1 , wherein the sleeve is disposed between 0.5 mm and 5 mm from sides of the SiC seed crystal and the growing SiC single crystal.

3. The system of claim 1 , wherein the gas-permeable membrane has a thickness between 3 mm and 12 mm.

4. The system of claim 1 , wherein the sleeve has a wall thickness between 4 mm and 15 mm.

5. The system of claim 1 , wherein the sleeve is cylindrical and the membrane is disposed at one end of the sleeve.

6. A physical vapor transport growth system comprising:
a growth chamber charged with SiC source material and a SiC seed crystal in spaced relation; and
an envelope that is at least partially gas-permeable disposed in the growth chamber and separating the growth chamber into a source compartment that includes the SiC source material and a crystallization compartment that includes the SiC seed crystal, said gas-permeable envelope formed of a material that is reactive to vapor generated by sublimation growth of a SiC single crystal on the SiC seed crystal in the crystallization compartment, wherein said gas-permeable envelope is positioned in the growth chamber such that the vapor generated by sublimation growth reacts with the material forming the envelope to produce a carbon-bearing vapor that acts as an additional source of carbon during the growth of the SiC single crystal on the SiC seed crystal;
wherein the envelope is comprised of: a sleeve that surrounds sides of the SiC seed crystal and the growing SiC single crystal; and a gas-permeable membrane disposed between the SiC source material and a surface of the SiC seed crystal that faces the SiC source material;
wherein the gas-permeable membrane is made of porous graphite having a density between 0.6 and 1.4 g/cm 3 and a porosity between 30% and 70%; and
wherein the graphite forming the gas-permeable membrane is comprised of graphite grains, each of which has a maximum dimension between 100 and 500 microns.

7. The system of claim 6 , wherein the sleeve is disposed between 0.5 mm and 5 mm from sides of the SiC seed crystal and the growing SiC single crystal.

8. The system of claim 6 , wherein the gas-permeable membrane has a thickness between 3 mm and 12 mm.

9. The system of claim 6 , wherein the sleeve has a wall thickness between 4 mm and 15 mm.

10. The system of claim 6 , wherein the sleeve is cylindrical and the membrane is disposed at one end of the sleeve.

Assignees

• Ii Vi Delaware Inc

Inventors

• Gupta Avinash
• Zwieback Ilya
• Semenas Edward
• Getkin Marcus
• Flynn Patrick

Classifications

• C30B29/36 Primary

  Carbides · CPC title

• C30B23/06

  Heating of the deposition chamber, the substrate or the materials to be evaporated · CPC title

• C30B23/005

  Controlling or regulating flux or flow of depositing species or vapour · CPC title

• C30B23/066

  Heating of the material to be evaporated · CPC title