Method of fabricating GaN

• US 20070092980A1
• Filed: 10/11/2006
• Published: 04/26/2007
• Est. Priority Date: 10/25/2005
• Status: Active Grant

• Current Assignee: Samsung Corning Precision Materials Company Limited (Corning Incorporated)
• Original Assignee: Samsung Corning Company Limited (Corning Incorporated)
• Inventors: Han, Jai-yong, Song, In-jae, Choi, Jun-sung
• Granted Patent: US 7,462,893 B2
• Time in Patent Office: Days
• US Class Current: 438/22
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/406 Gallium nitride
• CPC Class Codes: H01L 21/02389 Nitrides
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02513 Microstructure
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02658 Pretreatments cleaning in general H01L21/02041

Abstract

A method of fabricating a thick GaN layer includes forming a porous GaN layer having a thickness of 10-1000 nm by etching a GaN substrate in a reaction chamber in an HCl and NH₃ gas atmosphere and forming an in-situ GaN growth layer in the reaction chamber. The method of forming the porous GaN layer and the thick GaN layer in-situ proceeds in a single chamber. The method is very simplified compared to the prior art. In this way, the entire process is performed in one chamber, and in particular, GaN etching and growth are performed using an HVPE process gas such that costs are greatly reduced.

Claims

1. A method of forming a porous GaN layer having a thickness of 10-1000 nm comprising:

etching a GaN substrate in a reaction chamber in an HCl and NH₃ gas atmosphere.

2. The method of claim 1, wherein the GaN substrate is a freestanding GaN substrate.

3. The method of claim 1, wherein the GaN substrate is a GaN substrate layer formed by growing GaN on a sapphire substrate in the reaction chamber before the forming of the porous GaN layer.

4. The method of claim 1, wherein the etching of the GaN substrate is carried out at a temperature greater than 1000°

C.

5. The method of claim 1, wherein the etching of the GaN substrate is performed using a hydride vapor phase epitaxy (HVPE) system.

6. The method of claim 1, wherein the etching of the GaN substrate is carried out by providing HCl at a rate of 100 sccm and NH₃ at a rate of 1000 sccm at atmospheric pressure in a buffer gas of N₂ supplied at a rate of 8000 sccm.

7. The method of claim 4, wherein the etching of the GaN substrate is carried out by providing HCl at a rate of 100 sccm and NH₃ at a rate of 1000 sccm at atmospheric pressure in a buffer gas of N₂ supplied at a rate of 8000 sccm.

8. A method of fabricating GaN comprising:

forming a porous GaN layer having a thickness of 10-1000 nm by etching a GaN substrate in a reaction chamber in an HCl and NH₃ gas atmosphere; and

forming the GaN growth layer on the porous GaN layer to a predetermined thickness by supplying a GaN source to the reaction chamber.

9. The method of claim 8, wherein the GaN substrate is a freestanding GaN substrate.

10. The method of claim 8, wherein the GaN substrate is a GaN substrate layer formed by growing GaN on a sapphire substrate in the reaction chamber before the forming of the porous GaN layer.

11. The method of claim 8, wherein the etching of the GaN substrate is carried out at a temperature greater than 1000°

C.

12. The method of claim 8, wherein the etching of the GaN substrate is performed using a hydride vapor phase epitaxy (HVPE) system.

13. The method of claim 8, wherein the etching of the GaN substrate is carried out by providing HCl at a rate of 100 sccm and NH₃ at a rate of 1000 sccm at atmospheric pressure in a buffer gas of N₂ supplied at a rate of 8000 sccm.

14. The method of claim 11, wherein the etching of the GaN substrate is carried out by providing HCl at a rate of 100 sccm and NH₃ at a rate of 1000 sccm at atmospheric pressure in a buffer gas of N₂ supplied at a rate of 8000 sccm.

15. The method of claim 8, wherein the forming of the porous GaN layer and the forming the GaN growth layer take place in situ in a single chamber.