Patent ID: 7678597

Claim:
A method of manufacturing a semiconductor device, comprising (a) forming a gallium-nitride-based semiconductor structure on a substrate, said semiconductor structure including a p-type gallium-nitride contact layer in an uppermost part; (b) selectively removing an upper part of said semiconductor structure, including part of said contact layer, said semiconductor structure thereafter including a ridge or a mesa that includes the remainder of said contact layer that has not been removed, and an other-than-ridge or an other-than-mesa area from which said contact layer has been removed; (c) forming an insulating film on a side face of either said ridge or said mesa and on either said other-than-ridge area or said other-than-mesa area, but not forming said insulating film on a surface of either said ridge or said mesa that is not a side face of either said ridge or said mesa; (d) forming an oxide covering the surface that is not a side face of either said ridge or said mesa; and (e) forming a metal electrode completely covering said oxide and said insulating film, wherein forming a metal electrode includes (e-1) forming said metal electrode of Pd and a high-melting-point metal on said oxide, and (e-2) after forming said metal electrode of Pd and a high-melting point metal on said oxide, performing a heat treatment in a gas other than oxygen.