Patent ID: 8264039

Claim:
A high-voltage MOSFET, comprising: a substrate that includes at least: a source well region of a first conductivity type having a source contact; a drain well region of the first conductivity type having a drain contact; a gate well region of a second conductivity type, disposed between the source well region and the drain well region, coming into contact with the source well region at a first junction and coming into contact with the drain well region at a second junction, wherein the gate well region is further disposed under a conductive gate and extends no further laterally than the conductive gate and the source well and the drain well regions, a first biasing well region of the second conductivity type having a first biasing well contact; a first isolation structure disposed within one of the source well region and the drain well region between the gate well region and the contact of the one of the source well region and the drain well region, the first isolation structure extending within the one of the source well region and the drain well region to a depth deeper than the first junction or the second junction; and a deep well region of the second conductivity type extending under the source well region and the drain well region at a depth deeper than the first isolation structure and electrically coupled to the gate well region and the first biasing well region.