Wide-band-gap reverse-blocking MOS-type semiconductor device

摘要

A wide-band-gap reverse-blocking MOS-type semiconductor device includes a SiC n--type drift layer; a p+-type substrate on the first major surface side of the drift layer; a trench extending through a p+-type substrate into the drift layer; a titanium electrode in the trench bottom that forms a Schottky junction with the SiC n--type drift layer; an active section including a MOS-gate structure on the second major surface side of the drift layer facing to the area, in which the Schottky junctions are formed; a breakdown withstanding section surrounding the active section; and a trench isolation layer surrounding the breakdown withstanding section, the trench isolation layer extending from the second major surface of the drift layer into p+-type substrate and including insulator film buried therein. The device facilitates making a high current flow with a low ON-voltage and exhibits a very reliable reverse blocking capability.