Patent ID: 6706615
Filing Date: 2004-03-16
Classification: H01L

Abstract:
A method of manufacturing a transistor having a semiconductor substrate having a drain layer of a first conductivity type and an opposite conductive region of a second conductivity type in contact with the drain layer; comprising steps of:forming a deep trench reaching from a surface of the opposite conductive region to the drain layer in the semiconductor substrate, wherein a bottom of deep trench is positioned in the drain layer; disposing a semiconductor filler of the second conductivity type on a bottom of the deep trench, wherein top of the semiconductor filler is deeper than a bottom of the opposite conductive region; forming a gate insulating film on an inner side surface of a gate trench composed of an upper part than the top of semiconductor filler in the deep trench; forming a gate electrode insulated from the semiconductor filler in the gate trench to contact with the gate insulating film, and forming a source region of the first conductivity type on a surface within the opposite conductive region to contact with the gate insulating film.