Semiconductor device with a high breakdown voltage.

摘要

There is disclosed a power transistor comprising a semiconductor substrate (1) having a PN junction exposed on a major surface of the semiconductor substrate, and a semiinsulative polysilicon film (16) formed on the major surface, the polysilicon film covering the PN junction, the polysilicon film containing at least one of carbon, oxygen, and nitrogen, and the polysilicon film having a thickness of about 3,000 Å.