Patent ID: 8610204

Claim:
A semiconductor device comprising: a first conductivity type drift region formed in a semiconductor substrate; a second conductivity type body region formed at an upper surface of the semiconductor substrate on an upper surface side of the drift region; a first conductivity type first semiconductor region formed on a part of an upper surface of the body region; and a trench gate type insulated gate penetrating the first semiconductor region and the body region, and formed to a depth at which the insulated gate contacts the drift region, wherein a part of the insulated gate on a drift region side relative to the body region becomes gradually deeper at a center portion than at a from both end portions to a center portion in a longitudinal direction of the insulated gate, and a bottom portion of the insulated gate has an arc-like pattern, wherein a trench width of the center portion of the insulated gate becomes wider than a trench width of each of the both end portions to the center portion of the insulated gate in a plan view of the semiconductor substrate.