Gallium Nitride Substrate and Gallium Nitride Film Deposition Method

• US 20080272377A1
• Filed: 04/30/2008
• Published: 11/06/2008
• Est. Priority Date: 05/02/2007
• Status: Abandoned Application

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Nakahata, Seiji
• Application Number:
  US12/111,971
• Publication Number:
  US 20080272377A1
• Time in Patent Office: Days
• US Class Current: 257/76
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/406 Gallium nitride
• CPC Class Codes: C30B 33/02 Heat treatment C30B33/04, C30B33/06 take precedence
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/02387 Group 13/15 materials
• CPC Class Codes: H01L 21/02389 Nitrides
• CPC Class Codes: H01L 21/02433 Crystal orientation
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02516 Crystal orientation
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02576 N-type
• CPC Class Codes: H01L 21/02609 Crystal orientation
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 29/045 by their particular orientation of crystalline planes
• CPC Class Codes: H01L 29/2003 Nitride compounds
• CPC Class Codes: H01L 29/66143 Schottky diodes
• CPC Class Codes: H01L 29/66462 with a heterojunction interface channel or gate, e.g. HFET, HIGFET, SISFET, HJFET, HEMT
• CPC Class Codes: H01L 33/0075 comprising nitride compounds

Abstract

Affords high-carrier-concentration, low-cracking-incidence gallium nitride substrates and methods of forming gallium nitride films. A gallium nitride film 52 in which the carrier concentration is 1×10¹⁷ cm⁻³ or more is created. Initially, a gallium nitride layer 51 including an n-type dopant is formed onto a substrate 50. Then, the gallium nitride layer 51 formed on the substrate 50 is heated to form a gallium nitride film 52.

Claims

1. A method of deposition-forming a gallium nitride film having a carrier concentration of at least 1×

10¹⁷ cm<sup>−

3</sup>, the gallium-nitride-film deposition method comprising;

a step of forming on a substrate a gallium nitride layer containing an n-type dopant; and

a step of heating the gallium nitride layer formed on the substrate.

2. A gallium-nitride-film deposition method as set forth in claim 1, wherein the gallium nitride layer is heated at a temperature of 800°

C. or more for 5 minutes or more.

3. A gallium-nitride-film deposition method as set forth in claim 1, wherein the gallium nitride layer is heated at a ramp-down rate of 50°

C./min or less.

4. A gallium-nitride-film deposition method as set forth in claim 1, wherein the surface of the gallium nitride layer is inclined from the gallium nitride layer'"'"'s (0001) plane at an angle of 0.03°

or more.

5. A gallium-nitride-film deposition method as set forth in claim 1, wherein the gallium nitride layer has a dislocation density of 1×

10⁷ cm<sup>−

2</sup> or less.

6. A gallium-nitride-film deposition method, comprising:

a step of forming onto a substrate a gallium nitride layer having a carrier concentration of 1×

10¹⁷ cm<sup>−

3</sup> or more and including an n-type dopant;

wherein

the surface of the gallium nitride layer is inclined from the gallium nitride layer'"'"'s (0001) plane at an angle of 0.03°

or more.

7. A gallium-nitride-film deposition method as set forth in claim 6, wherein the gallium nitride layer has a dislocation density of 1×

10⁷ cm<sup>−

2</sup> or less.

8. A gallium nitride substrate characterized by:

carrier concentration in the gallium nitride substrate being 1×

10¹⁷ cm<sup>−

3</sup> or more;

incorporating an n-type dopant; and

having a surface inclined from the gallium nitride substrate'"'"'s (0001) plane at an angle of 0.03°

or more.

9. A gallium nitride substrate as set forth in claim 8, wherein the dislocation density of the gallium nitride substrate is 1×

10⁷ cm<sup>−

2</sup> or less.