Patent ID: 7452789
Filing Date: 2008-11-18
Classification: C30B,H01L

Abstract:
1. A method for forming an underlayer composed of a GaN-based compound semiconductor, the method comprising the steps of: (A) forming a strip seed layer composed of a GaN-based compound semiconductor on a surface of a sapphire substrate; (B) forming a crystal growth promoting layer composed of a GaN-based compound semiconductor on a top surface and both side surfaces of the seed layer, and on an exposed surface of the sapphire substrate; and (C) epitaxially growing an underlayer composed of a GaN-based compound semiconductor from a part of the crystal growth promoting layer on the top surface of the seed layer, a part of the crystal growth promoting layer on both the side surfaces of the seed layer, and a part of the crystal growth promoting layer on the exposed surface of the sapphire substrate.