Method of preparing a silicon carbide crystal by deposition onto at least a pair of conductive heating elements

Patent metadata

Field	Value
Publication number	US-12338544-B2
Application number	US-202218054439-A
Country	US
Kind code	B2
Filing date	Nov 10, 2022
Priority date	Nov 11, 2021
Publication date	Jun 24, 2025
Grant date	Jun 24, 2025

Abstract

A method of preparing a high-purity silicon carbide (SiC) crystal, and more specifically, to a method of preparing high-purity SiC having an extremely low impurity content in an excellent yield and in large quantities. The method including preparing a reactor containing a reaction chamber; heating the conductive heating element in the reaction chamber; mixing a silicon precursor, a carbon precursor, and a carrier gas; injecting the mixed gas into the reaction chamber, depositing SiC on the conductive heating element and harvesting the deposited SiC crystals.

First claim

The invention claimed is:

1. A method of preparing a high-purity SiC crystal, comprising:
i) preparing a reactor containing a reaction chamber, wherein the reactor comprises a pair of electrodes connected to a power source and at least one pair of conductive heating elements electrically connected to the electrodes;
ii) heating the at least one pair of conductive heating elements, wherein the conductive heating element is carbon fiber reinforced carbon (CFRC);
iii) mixing a silicon source precursor, a carbon source precursor, and a carrier gas;
iv) injecting the mixed gas into the reaction chamber;
v) depositing SiC on the at least one pair of conductive heating elements; and
vi) harvesting the deposited SiC crystals by separating the same from the at least one pair of conductive heating elements,
wherein an atomic ratio of Si:C between the silicon source precursor and the carbon source precursor in the mixed gas is 0.75 to 1.5:1.

2. The method of claim 1 , wherein the temperature inside the reaction chamber is 1,000° C. to 1,500° C.

3. The method of claim 1 , wherein the temperature of the conductive heating element is raised to 1,000° C. to 1,800° C.

4. The method of claim 1 , wherein the at least one pair of the conductive heating elements has one or more pairs of filaments.

5. The method of claim 1 , wherein a SiC deposition rate on the at least one pair of conductive heating elements is 10 g/hr or more.

6. The method of claim 1 , wherein the silicon source precursor is one or more selected from trichlorosilane (TCS), dichlorosilane (DCS), silicon tetrachloride (STC) and monosilane.

7. The method of claim 6 , wherein the silicon source precursor is trichlorosilane (TCS).

8. The method of claim 1 , wherein the carbon source precursor is propane (C 3 H 8 ).

9. The method of claim 1 , wherein the carrier gas is hydrogen (H 2 ).

10. The method of claim 1 , wherein an atomic ratio of Si:C between the silicon source precursor and the carbon source precursor in the mixed gas is 1:1.

Assignees

• Oci Co Ltd

Inventors

• Kim Gabok
• Kang Byungchang
• Park Byunghyun
• Jeon Junki
• Jeong Changwon
• Chyun Seungan

Classifications

• C30B29/36

  Carbides · CPC title

• C30B25/18

  characterised by the substrate · CPC title

• C01P2006/80

  Compositional purity · CPC title

• C01B32/977

  Preparation from organic compounds containing silicon · CPC title

• C23C16/01

  on temporary substrates, e.g. substrates subsequently removed by etching · CPC title