Patent ID: 8912598

Claim:
A semiconductor device, comprising: a semiconductor region including a first conductivity type having a first doping profile; a source region near a working top surface of the semiconductor region; a drain region near the working top surface and laterally offset from the source region; a gate located above the working top surface and located laterally between the source and drain regions; and a drift region located laterally between the gate and the drain region and at least partially overlapping with the gate and drain regions, the drift region comprising: a shallow portion extending laterally from the drain region toward the gate, the shallow portion comprising the second conductivity type having a peak doping concentration greater than an average drift region doping concentration; and a deep portion located at a greater depth within the semiconductor region than the shallow region, the deep portion comprising the second conductivity type having a peak doping concentration less than the average drift region doping concentration; wherein the deep portion extends laterally from the drain region toward the gate but not as far as the shallow portion; and wherein the shallow and deep portions are vertically separated along at least a portion of their overlapping width by a region of the first conductivity type in the lateral region extending from the gate toward the drain region.