Silicon based melting composition and manufacturing method for silicon carbide single crystal using the same

Patent metadata

Field	Value
Publication number	US-11873576-B2
Application number	US-201916630952-A
Country	US
Kind code	B2
Filing date	May 22, 2019
Priority date	May 25, 2018
Publication date	Jan 16, 2024
Grant date	Jan 16, 2024

Abstract

A silicon-based molten composition according to an exemplary embodiment is used in a solution growing method for forming a silicon carbide single crystal, includes silicon (Si), yttrium (Y), and iron (Fe), and is expressed in Formula 1.SiaYbFec  [Formula 1]In Formula 1, the a is equal to or greater than 0.4 and equal to or less than 0.8,the b is equal to or greater than 0.2 and equal to or less than 0.3, and the c is equal to or greater than 0.1 and equal to or less than 0.2.

First claim

What is claimed is:

1. A method for manufacturing a silicon carbide single crystal, comprising:
preparing a silicon carbide seed crystal;
preparing a silicon-based molten composition including silicon (Si), yttrium (Y), and iron (Fe), and as expressed in Formula 1;
forming a molten solution including the silicon-based molten composition and carbon (C); and
obtaining the silicon carbide single crystal on the silicon carbide seed crystal from the surface of the molten solution:
Si a Y b Fe c   [Formula 1]

wherein, in Formula 1, the a is equal to or greater than 0.5 and equal to or less than 0.7, the b is equal to or greater than 0.2 and equal to or less than 0.3, and the c is equal to or greater than 0.1 and equal to or less than 0.2,
wherein in the obtaining of the silicon carbide single crystal, a yttrium silicide is not precipitated, and
wherein a growing speed of the silicon carbide single crystal is equal to or greater than 0.1 mm/h.

2. The method of claim 1 , wherein
the b is equal to or greater than 0.2 and equal to or less than 0.25, and the c is equal to or greater than 0.15 and equal to or less than 0.2.

3. The method of claim 1 , wherein
the forming of the molten solution includes inserting the silicon-based molten composition into a crucible and heating the silicon-based molten composition in the crucible.

4. The method of claim 3 , wherein
the heating includes heating the molten solution to be 1800 degrees (° C.).

5. The method of claim 3 , wherein
a carbon solubility of the molten solution is in a saturated state.

6. The method of claim 5 , wherein
a temperature gradient of −20° C./cm is formed in a direction from the inside of the molten solution to the surface of the molten solution, and the silicon carbide seed crystal is allowed to contact the surface of the molten solution.

7. The method of claim 1 , wherein the silicon-based molten composition consists of silicon (Si), yttrium (Y), and iron (Fe), and as expressed in the Formula 1.

Assignees

• Lg Chemical Ltd

Inventors

• Lee Horim
• Kim Junghwan
• Chung Chanyeup
• Ko Jung Min

Classifications

• C30B15/14 Primary

  Heating of the melt or the crystallised materials · CPC title

• C30B19/04 Primary

  the solvent being a component of the crystal composition · CPC title

• C30B29/36 Primary

  Carbides · CPC title

• C30B19/062

  Vertical dipping system · CPC title

• C30B15/36

  characterised by the seed, e.g. its crystallographic orientation · CPC title