Patent ID: 8723317

Claim:
A trench MOSFET with embedded schottky rectifier, comprising: a substrate of a first conductivity type; an epitaxial layer of said first conductivity type onto said substrate, wherein said epitaxial layer has a lower doping concentration than said substrate; a plurality of gate trenches formed in said epitaxial layer and filled with a conductive material padded by a gate oxide layer; a plurality of body regions of a second conductivity type formed in an upper portion of said epitaxial layer and between two adjacent said gate trenches; a plurality of source regions of said first conductivity type formed near a top surface of said body regions and flanking said gate trenches in an active area; a plurality of trenched source-body contacts formed in an active area, each filled with a contact metal plug, penetrating through said source regions and said body regions and extending into said epitaxial layer, wherein said trenched source-body contacts have a depth shallower than said gate trenches but deeper than said body regions; and at least one anti-punch through implant region formed along at least a portion of sidewalls of said trenched source-body contacts and below said source regions; wherein said source regions have a higher doping concentration and a greater junction depth along sidewalls of said trenched source-body contacts than along adjacent channel regions near said gate trenches at a same distance from the top surface of said epitaxial layer.