Patent ID: 6917054

Claim:
A semiconductor device including: a first conductivity type substrate comprised of a semiconductor having a band gap equal to or greater than 2.0 eV and having a low impurity concentration; a first region formed in a first plane of the substrate and having the same first conductivity type as that of the substrate and having a resistance lower than that of the substrate; a first electrode formed in another plane of the first region; a second region formed in a second plane of the substrate and having said first conductivity type of that of the substrate; and a second electrode formed on the second region, the semiconductor device comprising: a trench formed in the second plane; a control region formed from a bottom of the trench into the substrate and having a different conductivity type than that of the substrate; and a control electrode formed on the control region, wherein the second electrode is formed over the control electrode through an insulating film, and wherein the control region having the different conductivity type from that of the substrate is formed on at least a part of sidewalls of the trench such that the control region is contacted with the second region.