Patent ID: 6342709
Filing Date: 2002-01-29
Classification: H01L

Abstract:
A wide-gap semiconductor device comprising:a semiconductor substrate exhibiting a first conductivity type; a semiconductor layer exhibiting a second conductivity type opposite to said first conductivity type deposited on said semiconductor substrate and forming a junction to said semiconductor substrate; at least one concave portion penetrated through said semiconductor layer to reach and cut partially into said semiconductor substrate; a first semiconductor region exhibiting said second conductivity type and having an impurity concentration higher than that of said semiconductor substrate, formed in said semiconductor substrate at a bottom of said concave portion; an insulator layer formed on an inner surface of said concave portion; a gate insulated by said insulator layer with said semiconductor substrate and said semiconductor layer and at least partially formed in said concave portion; a second semiconductor region exhibiting said first conductivity type formed at a surface of said semiconductor layer with a designated depth at a peripheral area of said gate surrounded by said insulator layer in said semiconductor layer; a first electrode formed on said semiconductor layer and said second semiconductor region and defined to be electrically conductive to said semiconductor layer and said second semiconductor region; and a second electrode defined at another portion of said semiconductor substrate, wherein said semiconductor substrate has a first semiconductor layer formed on another semiconductor layer having a higher electric conductivity, said first semiconductor layer having a conductivity type identical to that of said another semiconductor layer and an electric conductivity lower than that of said semiconductor layer.