Reduction threading dislocations by amorphization and recrystalization

摘要

A method for providing an epitaxial layer[14] of a first material over a substrate[11] comprising a second material having a lattice constant different from that of the first material. In the method of the present invention, a first layer of the first material is grown on the substrate[11]. A portion of the first layer is treated to render that portion amorphous. The amorphous portion is then annealed at a temperature above the recrystallization point of the amorphous portion, but below the melting point of the crystallized portion of the first layer thereby recrystallizing the amorphous portion of the first layer. The first layer may rendered amorphous by ion implantation. The method may be used to generate GaN layers on sapphire having fewer dislocations than GaN layers generated by conventional deposition techniques.