Lateral power semiconductor device for high frequency power conversion system, has isolation layer formed over substrate for reducing minority carrier storage in substrate

Abstract

A lateral power semiconductor device has a substrate and an isolation layer formed over the substrate for reducing minority carrier storage in the substrate. A well region is formed over the isolation layer. A source region, drain region, and channel region are formed in the well. A first region is formed on a surface of the lateral power semiconductor device adjacent to the source region. The lateral power semiconductor device has a body diode between the first region and drain region. The isolation layer confines the minority carrier charge from the body diode to a depth of less than 20 μm from the surface of the lateral power semiconductor device. In one embodiment, the isolation layer is a buried oxide layer and the substrate is an n-type or p-type handle wafer. Alternatively, the isolation layer is an epitaxial layer and the substrate is made with N+ or P+ semiconductor material.