Patent ID: 8426949

Claim:
A mesa type semiconductor device comprising: a semiconductor substrate of a first general conductivity type; a first semiconductor layer of the first general conductivity type disposed on a surface of the semiconductor substrate, an impurity concentration of the first semiconductor layer being lower than an impurity concentration of the semiconductor substrate; a second semiconductor layer of a second general conductivity type disposed on a surface of the first semiconductor layer so as to form a PN junction between the first semiconductor layer and the second semiconductor layer; and an exterior sidewall portion comprising a first exterior sidewall portion disposed above the PN junction and a second exterior sidewall portion extending from the first exterior sidewall portion and covering an edge of the PN junction, the first exterior sidewall portion and the second exterior sidewall portion slanting in different directions so that a portion connecting the first and second exterior sidewall portions extrudes the farthest, at the exterior sidewall portion, in a direction parallel to the surface of the semiconductor substrate on which the first semiconductor layer is disposed, the first exterior sidewall portion and the second exterior sidewall portion slanting with respect to a direction perpendicular to the surface of the semiconductor substrate on which the first semiconductor layer is disposed, and the exterior sidewall portion defining an edge of the mesa type semiconductor device in plan view of the semiconductor device.