Patent ID: 7843003

Claim:
An insulated gate semiconductor device comprising: a semiconductor layer of a first conductivity type; a first operation part provided in a surface of the semiconductor layer; a second operation part provided in the surface of the semiconductor layer so as to be smaller in area than the first operation part; a first channel region of a second conductivity type opposite from the first conductivity type provided in the first operation part; a first transistor provided in the first operation part and comprising a gate electrode; a second channel region of the second conductivity type provided in the second operation part; a second transistor provided in the second operation part and comprising a gate electrode; a gate connection electrode formed of a semiconductor and connected to the gates of the first and second transistors; and a gate wiring formed of a metal and disposed on the gate connection electrode so as to be electrically in contact with the gate connection electrode, wherein in plan view of the insulated gate semiconductor device the first operation part is disposed around the second operation part, in the plan view of the insulated gate semiconductor device the gate connection electrode and the gate wiring are disposed between the first operation part and the second operation part, the first operation part is formed in a rectangular shape, and curvatures of four corner portions of the rectangular shape are equal, and the first and second channel regions are disposed so as to be separated from each other by a distance which allows depletion layers to come into contact with each other, the depletion layers spreading in the semiconductor layer when a reverse voltage is applied to the first and second transistors.