Patent ID: 9093493
Filing Date: 2015-07-28
Classification: H01L

Abstract:
1. A wide bandgap insulated gate semiconductor device, comprising: a semiconductor substrate made of semiconductor having a bandgap wider than silicon; a first conductivity type drift layer over the semiconductor substrate, said drift layer having a low impurity concentration; a plurality of second conductivity type channel regions selectively disposed over the drift layer; first conductivity type semiconductor regions selectively disposed in respective surfaces in said channel regions, said first conductivity type semiconductor regions having a high impurity concentration; a plurality of second conductivity type base regions in contact with bottoms of the respective channel regions, said base regions having a high impurity concentration; a protruding drift layer portion that is a first conductivity type region interposed between said plurality of channel regions and said plurality of second conductivity type base regions thereunder; a gate electrode formed, through a gate insulating film, on the protruding drift layer portion and on respective surfaces of the channel regions; a first common electrode in contact with the first conductivity type semiconductor regions in said channel regions; and a second conductivity type floating region inside the protruding drift layer portion, having side faces respectively facing side faces of the second conductivity type base regions, the second conductivity type floating region having a high impurity concentration, wherein respective gaps between said second conductivity type base regions and said second conductivity type floating region defined by the respective side faces have a wide portion and a narrow portion.