Method for fabricating a III nitride film, an underlayer for fabricating a III nitride film and a method for fabricating the same underlayer

摘要

A method for fabricating a Group III nitride film is provided, including the steps of preparing a substrate, forming an underfilm and then forming the Group III nitride film on the underfilm. The underfilm is a Group III nitride including at least 50 atomic percent of elemental Al for each of the Group III elements of the underfilm Group III nitride. The surface of the underfilm includes a contoured portion and a flat region, and less than 50% of the surface is occupied by the flat region.