Patent ID: 8786011

Claim:
A semiconductor device, comprising: a semiconductor substrate; a drift region of first conductivity type which is provided on the semiconductor substrate; a plurality of first well regions of second conductivity type which are provided within the drift region and are partially exposed in a major surface of the drift region; a plurality of source regions of the first conductivity type which are located within the first well regions and are partially exposed in the major surface; three or more insulating gate portions which form channels reversed to the first conductivity type in part of the first well regions located between the drift region and source regions; and a first main electrode which forms a contact with the drift region exposed in the major surface to constitute a unipolar diode and is connected to the first well regions and the source regions, wherein the plurality of insulating gate portions have linear patterns parallel to each other when viewed in the normal direction of the major surface, between each pair of adjacent insulating gate portions, the first well regions and junction portions in which the first main electrode forms junctions with the drift region are arranged along the direction that the insulating gate portions extend, and the first well regions and the junction portions in which the first main electrode form junctions with the drift region are arranged in line along a direction vertical to the direction that the insulating gate portions extend, the channels are formed in the normal direction of the major surface and in the vertical direction to the normal of the major surface, and a length of the channels formed in the vertical direction to the normal of the major surface is longer than a length of the channels formed in the normal direction of the major surface.