Patent ID: 9349855
Filing Date: 2016-05-24
CPC Classification: H01L

Claim Text:
1. A wide band gap semiconductor device comprising: a wide band gap semiconductor substrate of a first conductivity type with a high impurity concentration; a drift layer of the first conductivity type with a low impurity concentration composed of a wide band gap semiconductor material on the substrate; a plurality of channel regions of a second conductivity type selectively arranged in a surface region of the drift layer and contacting the drift layer, with a specified distance between the channel regions; a source region of the first conductivity type selectively arranged in a surface region of the plurality of channel regions of the second conductivity type; a contact region of the second conductivity type, at least a portion of a channel region of the plurality of channel regions extending from a side surface of the drift layer to a side surface of the contact region; a source electrode in contact with a surface of the source region; and a gate electrode disposed over a surface of the surface region of the drift layer positioned between the plurality of channel regions and over surfaces of the plurality of channel regions each positioned between the surface region of the drift layer and the source region, intercalating a gate oxide film beneath the gate electrode; wherein the drift layer of the first conductivity type with a low impurity concentration composed of a wide band gap semiconductor material has a low impurity concentration not higher than 70% of an impurity concentration that is required to exhibit a withstand voltage of 1200 V at a minimum ON resistance.