Semiconductor device and method of manufacturing same

摘要

A concave channel type DMOS structure having an improved gate-to-source breakdown voltage are disclosed. By establishing a curvature at a corner portion of a lattice-like pattern in a groove portion for forming the concave channel structure, the shape of the tip of a three-dimensionally projecting portion of a semiconductor region determined by a plane angle of the corner portion in the lattice-like pattern and an inclination of the groove portion is rounded. That is, a three-dimensionally sharpened corner portion in the concave channel structure is rounded, and thereby electric field concentration at the corner portion is suppressed.