Patent ID: 7816720

Claim:
A trench semiconductor power MOSFET comprising a plurality of trench MOSFET cells with each cell composed of a first trenched gates surrounded by a source region heavily doped with a first conductivity type in an active area encompassed in a body region of a second conductivity type above a drain region disposed on a bottom surface of a low-resistivity substrate of said first conductivity type, wherein: said trench MOSFET cells are formed in an epitaxial layer with said first conductivity type over said low-resistivity substrate, and with a lower doping concentration than said low-resistivity substrate; said source region has a doping concentration along a channel region lower than along a trenched source-body contact region at a same distance from the surface of said epitaxial layer, and a source junction depth is shallower along said channel region than along said trenched source-body contact, and the doping profile of said source region along the surface of said epitaxial layer has a Gaussian-distribution from said trenched source-body contact region to said channel region; said first trenched gates and at least a second trenched gate having a wider trench gate than said first trenched gates filled with doped poly padded with a first insulation layer as gate oxide; a second insulating layer as a thick oxide interlayer covering the top surface of said epitaxial layer and said first and second trenched gates; a plurality of said trenched source-body contacts penetrating through said second insulating layer and said source regions, and extending into said body region to contact both said source regions and said body regions; at least a trenched gate contact penetrating through said second insulating layer and extending into said doped polysilicon in said second trenched gate; and a body contact resistance reduction area heavily doped with said second conductivity type around said trenched source-body contact region.