AlGaN substrate and production method thereof

• US 8,882,910 B2
• Filed: 05/04/2009
• Issued: 11/11/2014
• Est. Priority Date: 03/28/2005
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Amano, Hiroshi, Bando, Akira
• Primary Examiner(s): SONG, MATTHEW J
• Application Number:
  US12/434,916
• Publication Number:
  US 20090239357A1
• Time in Patent Office: 2,017 Days
• Field of Search: 117/84, 117/88, 117/97, 117/104, 117/915, 117/952, 16/84, 16/88, 16/97, 161/04, 169/15, 169/52
• US Class Current: 117/104
• CPC Class Codes: C03B 25/02 in a discontinuous way
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: Y10S 117/915 Separating from substrate

Abstract

A substrate is formed of Al_xGa_1-xN, wherein 0<x≦1. The substrate is a single crystal and is used producing a Group III nitride semiconductor device. A method for producing a substrate of Al_xGa_1-xN, wherein 0<x≦1, includes the steps of forming a layer of Al_xGa_1-xN, wherein 0<x≦1, on a base material and removing the base material. The method adopts the MOCVD method using a raw material molar ratio of a Group V element to Group III element that is 1000 or less, a temperature of 1200° C. or more for forming the layer of Al_xGa_1-xN, wherein 0<x≦1. The base material is formed of one member selected from the group consisting of sapphire, SiC, Si, ZnO and Ga₂O₃. The substrate is used for fabricating a Group III nitride semiconductor device.

Claims

1. A method for producing a substrate of Al_xGa_1-xN, wherein 0<

x≦

1, comprising the steps of;

first, either introducing an Al raw material alone, or introducing Al raw material and nitrogen (N) raw material where a molar ratio V/III being adjusted to 1 to 100;

next, adjusting a molar ratio of a Group V element to a Group III element that is 200 or less and forming a layer of Al_xGa_1-xN, wherein 0<

x≦

1, on a base material at a temperature of 1400°

C. or higher by a MOCVD method; and

subsequently, removing the base material.

2. A method according to claim 1, wherein the base material is formed of one member selected from the group consisting of sapphire, SiC, Si, ZnO and Ga₂O₃.