Patent ID: 6580123
Filing Date: 2003-06-17
Classification: H01L

Abstract:
A trench type MOSgated power semiconductor device comprising a water of silicon of one conductivity type; a plurality of spaced trenches formed into the top surface of said wafer and extending therein to a given depth; an insulation coating lining the side walls and bottom of said trench; a conductive gate body filling the interior of each of said trenches; a channel region of a second conductivity type extending into the top of said wafer to a first depth which is less than said given depth; a source region of said one conductivity type extending into said channel region to a second depth from the top of said wafer to define invertable channels along the sides of said trench in said channel region which extends between said first and second depths; a source electrode formed on the top surface of said wafer and connected to said source and channel regions; a drain electrode connected to the bottom of said wafer; and a shallow diffusion of the second conductivity type surrounding the bottom of each of said trenches, said shallow diffusion having a concentration substantially less than that of said channel region and being at all times depleted by the built-in junction voltage at its junction to the surrounding one conductivity type material of said wafer.