Patent ID: 6730961
Filing Date: 2004-05-04
Classification: H01L

Abstract:
A semiconductor device comprising:a semiconductor substrate of a first conductivity type; and unit devices located in a surface portion of the semiconductor substrate; wherein each of the unit devices comprises: an oblong trench dug from the surface of the substrate; an oblong source region of a second conductivity type in the surface portion of the semiconductor substrate, the source region being spaced apart from the trench; an offset drain region of the second conductivity type formed along the surface of the substrate spaced apart from the source region, along a side wall of the trench and along a bottom wall of the trench; an oxide filling the trench; drain region of the second conductivity type in the surface portion of the semiconductor substrate facing to the source region across the trench; a gate insulation film on the surface portion of the semiconductor substrate between the source region and the offset drain region; a gate electrode on the gate insulation film; a source electrode connected electrically to the source region; a drain electrode connected electrically to the drain region; wherein a direction along a long edge portion of the drain region in a planar layout of the semiconductor device is defined as a y-direction; wherein a direction perpendicular to the y-direction in the planar layout of the semiconductor device is defined as an x-direction; wherein the trench is extended in the y-direction from short edge portions, extending in the x-direction, of the drain region; and wherein the short edge portions, extending in the x-direction, of the drain region are surrounded by the offset drain region.