Diamond semiconductor device, semiconductor module, and diamond semiconductor device production method

Abstract

Provided is a diamond semiconductor device having a trench portion on the front side thereof, said diamond semiconductor device comprising a diamond layer, a diamond epitaxial layer provided on the diamond layer, a gate insulating film provided above the epitaxial layer, and a gate electrode provided on the gate insulating film, wherein the epitaxial layer has a side wall portion provided on a side wall of the trench portion and a bottom portion provided on the bottom surface of the trench portion, and at least one of the side wall portion and the bottom portion has a thickness of not less than 10 nm but less than 200 nm.