Patent ID: 8252645
Filing Date: 2012-08-28
Classification: H01L

Abstract:
1. A method for manufacturing a metal oxide semiconductor field effect transistor (MOSFET) comprising a step of forming said MOSFET with a trenched gate surrounded by a source region encompassed in a body region above a drain region disposed on a bottom surface of a substrate, the method further comprising: covering said MOSFET cell with an insulation layer and applying a contact mask for opening a source-body contact trench extending through said source and body regions and into an epitaxial layer below said body region for filling a contact metal plug therein; forming an embedded Schottky diode by forming a Schottky barrier layer along sidewall of said source-body contact trench in said epitaxial layer and near a bottom of said source-body contact trench below said contact metal plug with said Schottky barrier layer having a barrier height for reducing a leakage current through said embedded Schottky diode during a reverse bias between said drain and said source and forming a source-dopant region below said source-body contact trench in contact with said Schottky barrier layer of said Schottky diode having a different dopant concentration from said epitaxial layer surrounding said body region supported on said semiconductor substrate.