Free HCL used during pretreatment and AlGaN growth to control growth layer orientation and inclusions

Patent metadata

Field	Value
Publication number	US-9023673-B1
Application number	US-201313917373-A
Country	US
Kind code	B1
Filing date	Jun 13, 2013
Priority date	Jun 15, 2012
Publication date	May 5, 2015
Grant date	May 5, 2015

Abstract

A method to grow single phase group III-nitride articles including films, templates, free-standing substrates, and bulk crystals grown in semi-polar and non-polar orientations is disclosed. One or more steps in the growth process includes the use of additional free hydrogen chloride to eliminate undesirable phases, reduce surface roughness, and increase crystalline quality. The invention is particularly well-suited to the production of single crystal (11.2) GaN articles that have particular use in visible light emitting devices.

First claim

What is claimed is:

1. A method for growing a group III-nitride article on a substrate comprising a) substrate treatment including exposure of the substrate to a gas mixture containing at least a fraction of aluminum chloride and a fraction of free hydrogen chloride, b) nucleation layer formation, c) AlGaN intermediate layer growth, and d) group III-nitride layer growth; wherein either or both of c) and d) includes hydrogen chloride in a gas stream, the group III-nitride article being grown in a semi-polar direction.

2. The method of claim 1 wherein the group III-nitride layer growth is in a gas stream containing at least one of AlCl and GaCl, the hydrogen chloride being at least 25% of the total chloride containing gas.

3. The method of claim 1 wherein the group III-nitride layer growth is in a gas stream containing at least one of AlCl and GaCl, and the hydrogen chloride is in the range of 45 approximately to approximately 75% of the total chloride containing gas.

4. The method of claim 1 wherein the nucleation layer formation is in a gas stream containing chlorides, and the hydrogen chloride is in the range of approximately 3% to approximately 70% of the total chloride containing gas.

5. The method of claim 1 wherein the nucleation layer formation is in a gas stream containing chlorides, and the hydrogen chloride is in the range of approximately 10% to approximately 20% of the total chloride containing gas.

6. The method of claim 1 wherein for the group III-nitride layer growth is in a chloride containing gas stream and wherein the HCl is in the range of approximately 0% to approximately 75%.

7. The method of claim 1 wherein for the group III-nitride layer growth is in a chloride containing gas stream and wherein the HCl is in the range of approximately 25% to approximately 50% of the total chloride containing gas.

8. The method of claim 1 wherein the group III-nitride article is a {11.2}-oriented film consisting predominantly of GaN on an m-plane sapphire substrate.

9. The method of claim 8 for growing a semi-polar group III-nitride article wherein high temperature nitridation in NH 3 flow is used for substrate treatment.

10. The method of claim 8 for growing a semi-polar group III-nitride article wherein {11.2} AlGaN is grown as a buffer layer on the treated sapphire substrate.

11. The method of claim 10 wherein aluminum chloride, gallium chloride, ammonia and free hydrogen chloride are mixed with a carrier gas to grow an {11.2}-oriented AlGaN layer while suppressing non-{11.2} orientations from forming.

12. The method of claim 8 for growing a semi-polar group III-nitride article wherein the substrate is nitridated with a gas flow including ammonia during the substrate treatment step.

13. The method of claim 8 for growing a semi-polar group III-nitride article wherein gallium chloride, ammonia, and additional free-HCl are mixed with carrier gases to grow {11.2} GaN while suppressing formation of non-{11.2} orientations.

Assignees

• Ostendo Technologies Inc

Inventors

• Shapovalov Lisa
• Kovalenkov Oleg
• Ivantsov Vladimir
• Soukhoveev Vitali
• Syrkin Alexander
• Usikov Alexander

Classifications

• H10P14/3216

  Nitrides · CPC title

• H10P14/2922

  being non-crystalline insulating materials, e.g. glass or polymers · CPC title

• H10P14/3416 Primary

  Nitrides · CPC title

• H01L21/0254 Primary

  Electricity · mapped topic