Patent ID: 7485900

Claim:
A nitride semiconductor device comprising: a substrate having a first main surface and a second main surface; a nitride semiconductor layer formed on the first main surface of the substrate; and an electrode formed on the second main surface of the substrate, the substrate including first edge portions and second edge portions with at least one of the first edge portions including dislocation concentration regions, the electrode having electrode formation regions and recess regions that are disposed on the dislocation concentration regions on the second main surface of the substrate with at least the electrode formation regions directly contacting the substrate, the recess regions of the electrode being arranged as one of opening regions and thin film regions, the second main surface of the substrate being continuously exposed along at least one of the first and second edge portions of the substrate, and the electrode formation regions and the recess regions of the electrode being formed at least on the first edge portion including the dislocation concentration regions so that an edge surface of the first edge portion has a region roughly matching an edge surface of the electrode formation regions.