Patent ID: 6903416
Filing Date: 2005-06-07
Classification: H01L

Abstract:
1. A trench transistor, comprising: a semi-conductor body of a first conduction type having a surface region; a semiconductor region of a second conduction type opposite to said first conduction type provided in said surface region of said semiconductor body and having a top surface; a trench formed in said semiconductor body and said semiconductor region and extending from said top surface of said semiconductor region to a level below said semiconductor region, said trench having a wall, a lower region, and an upper region; an insulation layer at least partially lining said wall of said trench and having an upper end; a conductive trench filling disposed in said lower region of said trench and having a top side; an insulating trench filling disposed in said upper region of said trench, having a top surface, and adjoining said top side of said conductive trench filling; and a semiconductor zone of said first conduction type provided along said insulation layer in said semiconductor region and having a lower edge; said upper end of said insulation layer and said top surface of said insulating trench filling at least partially disposed above said surface of said semiconductor region; said lower edge of said semiconductor zone being curved and lying lower than said top side of said conductive trench filling; a spacer provided along said insulation layer and disposed above said top surface of said semiconductor region and serving as a dopant source for said semiconductor zone; and a channel zone running along said insulation layer in said semiconductor region.