Termination Design For Trench Superjunction Power MOSFET

摘要

A plurality of trench stripes are disposed in parallel in an epitaxial layer on a drain and extends from a top region to a bottom region of a first surface of the semiconductor. A first polysilicon layer is in each of the trench stripes. The first polysilicon layer extends between the drain and the first surface proximal to the top region and the bottom region, and between the drain and a level below the first surface in a middle region between the top region and the bottom region. A second polysilicon layer is over the first polysilicon layer in the middle region, wherein the first poly silicon layer forms a shield, and the second polysilicon layer forms a gate. A source is in a silicon mesa stripe surrounding the first trench stripe.