Method for manufacturing gallium nitride compound semiconductor

• US 6,121,121 A
• Filed: 07/27/1999
• Issued: 09/19/2000
• Est. Priority Date: 11/07/1997
• Status: Expired due to Fees

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Koide, Norikatsu
• Primary Examiner(s): PHAM, LONG
• Application Number:
  US09/361,624
• Time in Patent Office: 420 Days
• Field of Search: 438/479, 438/481, 438/341
• US Class Current: 438/481
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/02381 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02502 consisting of two layers
• 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 21/02639 Preparation of substrate for selective deposition
• CPC Class Codes: H01L 21/02647 Lateral overgrowth

Abstract

An Al₀.15 Ga₀.85 N layer 2 is formed on a silicon substrate 1 in a striped or grid pattern. A GaN layer 3 is formed in regions A where the substrate 1 is exposed and in regions B which are defined above the layer 2. At this time, the GaN layer grows epitaxially and three-dimensionally (not only in a vertical direction but also in a lateral direction) on the Al₀.15 Ga₀.85 N layer 2. Since the GaN layer grows epitaxially in the lateral direction as well, a GaN compound semiconductor having a greatly reduced number of dislocations is obtained in lateral growth regions (regions A where the substrate 1 is exposed).

Claims

1. A method for manufacturing a gallium nitride group compound semiconductor, comprising the steps of growing a first gallium nitride group compound semiconductor on a substrate;

etching said first gallium nitride group compound semiconductor into an island pattern such as a dot pattern, a striped pattern, or a grid pattern such that substrate-exposed portions are formed in a scattered manner; and

growing a second gallium nitride group compound semiconductor which causes epitaxial growth from an island or islands of said first gallium nitride group compound semiconductor serving as nuclei (seeds) but which does not cause epitaxial growth from the substrate-exposed portions, so that said second gallium nitride group compound semiconductor is formed by lateral growth above said substrate-exposed portions.

2. A method for manufacturing a gallium nitride group compound semiconductor according to claim 1, wherein said substrate is made of sapphire, silicon, or silicon carbide.

3. A method for manufacturing a gallium nitride group compound semiconductor according to claim 1, wherein the substrate is formed of silicon;

said first gallium nitride group compound semiconductor formed in an island pattern is formed of a gallium nitride group compound semiconductor containing aluminum, and said second gallium nitride group compound semiconductor is formed of a gallium nitride group compound semiconductor containing no aluminum.