Split-gate lateral diffused metal oxide semiconductor device

Abstract

A semiconductor device includes a source region, a drain region, and a drift region between the source and drain regions. A split gate is disposed over a portion of the drift region, and between the source and drain regions. The split gate includes first and second gate electrodes separated by a gate oxide layer. A self-aligned RESURF region is disposed within the drift region between the gate and the drain region. PI gate structures including an upper polysilicon layer are disposed near the drain region, such that the upper polysilicon layer can serve as a hard mask for the formation of the double RESURF structure, thereby allowing for self-alignment of the double RESURF structure.