Patent ID: 6538280
Filing Date: 2003-03-25
Classification: H01L

Abstract:
A trenched semiconductor device including at least a transistor, said trenched semiconductor device comprising:a semiconductor substrate, excluding silicon carbide, provided with at least one trench in a major surface thereof, the edge of said trench at said major surface being rounded, a prescribed portion of a sidewall of said trench serving as a channel of said transistor; an insulating film formed on the wall of the trench and extending onto the major surface of the semiconductor substrate, said insulating film serving as a gate insulating film of said transistor; and a conductive part filling up the trench and extending on to the insulating film, all around the trench, on the major surface of the semiconductor substrate, said conductive part serving as a gate of said transistor, wherein the thickness of the portion of the insulating film is increased at the top portion of the trench so that the thickness of the portion of the conductive part is reduced at the top portion of the trench.