Patent ID: 6844611
Filing Date: 2005-01-18
Classification: C30B,H01L

Abstract:
1. A III nitride epitaxial substrate comprising; a sapphire single crystal base material of which a crystal orientation of a main surface is inclined from the <0001> orientation by a range within 0.02-0.3 degrees and which includes a surface nitride layer at said main surface, and an III nitride underfilm which is formed on said main surface of said sapphire single crystal base material via said surface nitride layer and includes at least Al element, and of which a full width at half maximum at (10-12) reflection in X-ray rocking curve is 2000 seconds or below and of which a surface roughness Ra within 5 μm area is 3.5 Å, wherein the thickness of the m nitride underfilm is 0.5 μm or greater.