Patent ID: 8178922

Claim:
A trench semiconductor power MOSFET comprising a plurality of trench MOSFET of stripe cells with each stripe cell comprising: a substrate of a first conductivity type; an epitaxial layer of said first conductivity type over said substrate and having a lower doping concentration than said substrate; a plurality of body regions of a second conductivity type inside said epitaxial layer; a plurality of source regions of said first conductivity type near top surface of said body regions in an active area and having a higher doping concentration than said epitaxial layer; a plurality of first gate trenches reaching said epitaxial layer and surrounded by said source regions above said body regions, and each cell only have said source region and said body region between two adjacent first trenched gates; a first insulation layer lining the lower inner surface of said first gate trenches; a gate conductive layer filling partially within lower portion of each of said first gate trenches and close to said first insulation layer; a second insulation layer disposed inside of upper portion of said first gate trenches covering top surface of said gate conductive layer and said first insulation layer, and on top surface of said epitaxial layer; at least a body contact trench arranged next to the edge of said active area penetrating through said second insulation layer and extending into said body region; a first body contact region heavily doped with said second conductivity type inside said body region and wrapping at least the bottom of each said body contact trench, said first body contact region has a higher doping concentration than said body region; a first metal plug filling into upper portion of each of said first gate trenches; a second metal plug filling into each said body contact trench; a source metal connected to said source region on top of said source region and on sidewalls of top portion of said first gate trenches via said first metal plug, while connected to said body region via said second metal plugs filling in said body contact trench.