Semiconductor device and method of manufacturing semiconductor device

Abstract

A semiconductor device has a semiconductor substrate of a first conductivity type; a drift layer of the first conductivity type; a base layer of a second conductivity type; an active region through which a main current flows and having source regions of the first conductivity type, trenches, gate insulating films, and gate electrodes; and a termination region surrounding a periphery of the active region. The termination region has a conductive film electrically connected to the gate electrode, a field oxide film that insulates the conductive film from the drift layer, and a contact hole that penetrates through the conductive film and reaches the field oxide film. The contact hole is embedded in the field oxide film such that a thickness of the field oxide film below the contact hole has is 54 nm to 85 nm thinner than a thickness of the field oxide film outside the contact hole.