Semiconductor device and method for manufacturing the same

摘要

A semiconductor device according to the present invention includes: a semiconductor layer made of silicon; a trench formed by digging in from a top surface of the semiconductor layer; a gate insulating film formed on an inner wall surface of the trench and made of silicon oxide; a gate electrode embedded in the trench via the gate insulating film and made of a polysilicon doped with an impurity; and an oxidation-resistant metal film disposed on a top surface of the gate electrode and covering the top surface.