MOS transistor with surface accumulation region

摘要

The product of the on-resistance and the area of a high-voltage LDMOST is reduced by a factor of two to four by creating a surface accumulation region along the surface of the drift region 4 in the on- state of the device, it can be created by using a semi-insulating layer 10 over a thin field oxide region 6 covering the drift region 4 or via a fourth electrode located between the gate 8 and the drain 2, and held at a constant high voltage.