Patent ID: 8530942

Claim:
A semiconductor device, comprising: a semiconductor layer comprising a first region and a second region isolated from the first region; a source area of a first conductivity type provided on a surface of the first region; a drain area of the first conductivity type provided on a surface of the second region; a back-gate area of a second conductivity type provided on the surface of the first region, the back-gate area having a portion located closer to the drain area than the source area; a gate insulator on a surface of the semiconductor layer between the first region and the second region; a gate electrode on the gate insulator, a portion of the gate electrode on a side of the first region having a recessed portion above the portion of the back-gate area that is closer to the drain area than the source area; a source electrode contacting both the source area and the back-gate area; and a drain electrode contacting the drain area.