Patent ID: 8564051

Claim:
A power semiconductor device comprising: a semiconductor body that includes: a base region; a source region disposed on said base region; at least one high conductivity contact region disposed on said base region; a common conduction region below said base region; a plurality of trenches extending through said base region, each trench extending into said semiconductor body from a top surface of said semiconductor body and including a bottom and opposing sidewalls; a gate electrode disposed inside each trench and insulated from said base region by a respective gate insulation layer, said gate electrode including a bottom surface and a top surface which is below said top surface of said semiconductor body; an insulation plug residing over a respective top surface of a respective gate electrode and extending above said top surface of said semiconductor body; a buried source electrode in each trench disposed below and insulated from a respective gate electrode by an insulation interlayer substantially thinner than said insulation plug, said buried source electrode not extending beyond said common conduction region; at least one source electrode connector; a source contact electrically coupled to said at least one source electrode connector and extending over said insulation plugs, whereby said source contact is electrically connected to said buried source electrodes; and an insulation body disposed between said buried source electrodes and said common conduction region.