Patent ID: 7323724

Claim:
A nitride semiconductor device comprising: a semiconductor layer; an insulating layer being disposed on a portion of a surface of the semiconductor layer; a first electrode for establishing an ohmic contact and being disposed on another portion of the semiconductor layer; an adhesion layer being disposed on at least a portion of the first electrode; and a second electrode having a different shape from a shape of the first electrode; wherein at least a portion of the insulating layer is disposed between the first electrode and the semiconductor layer; and wherein the surface of the semiconductor layer on which the first electrode is disposed comprises an electrode formation region and an insulating layer formation region, wherein the first electrode further includes an upper layer and a lower layer, and the second electrode further includes an upper layer and a lower layer, wherein the upper layer of the first electrode and the lower layer of the second electrode each comprises an elemental metal, a compound or alloy including one of Pt, Pd, Rh, Ir, Ru, and Os.