Patent ID: 6992363
Filing Date: 2006-01-31
Classification: H01L

Abstract:
1. A dielectric separation type semiconductor device, comprising: a semiconductor substrate; a primary dielectric layer disposed adjacent to a whole region of a first main surface of said semiconductor substrate; a first conductivity type first semiconductor layer of a low impurity concentration disposed on a surface of said primary dielectric layer in opposition to said semiconductor substrate so that said primary dielectric layer is sandwiched between said first conductivity type first semiconductor layer and said semiconductor substrate; a first conductivity type second semiconductor layer of a high impurity concentration formed selectively on the surface of said first semiconductor layer; a second conductivity type third semiconductor layer of a high impurity concentration disposed so as to surround an outer peripheral edge of said first semiconductor layer with a distance; a ring-like insulation film disposed so as to surround an outer peripheral edge of said third semiconductor layer; a first main electrode disposed in contact with a surface of said second semiconductor layer; a second main electrode disposed in contact with a surface of said third semiconductor layer; a sheet-like back-surface electrode disposed adjacent to a second main surface of said semiconductor substrate on a side opposite to said first main surface of said semiconductor substrate; and a first auxiliary dielectric layer disposed below said second semiconductor layer, said first auxiliary dielectric layer having a concave shape; wherein a second auxiliary dielectric layer is disposed between said first auxiliary dielectric layer and said primary dielectric layer; and wherein said second auxiliary dielectric layer is junctioned to the semiconductor substrate and the first auxiliary dielectric layer.