Patent ID: 9318547
Filing Date: 2016-04-19
CPC Classification: H01L

Claim Text:
1. A wide bandgap insulated gate semiconductor device, comprising: a semiconductor substrate; a first conductivity type drift layer over the semiconductor substrate, the first conductivity type drift layer having a low impurity concentration; a trench-gate structure constituted of a gate electrode formed in a first trench through a gate insulating film, the first trench reaching the first conductivity type drift layer from an upper surface; a trench-first electrode structure constituted of a first electrode embedded in each of second trenches that are disposed along both sides of the trench-gate structure, or constituted of a second conductivity type region embedded in each of said second trenches, the second conductivity type region being in contact with a first electrode, said second trenches reaching the first conductivity type drift layer from said upper surface, said second conductivity type region having a high impurity concentration; a second conductivity type floating region below or at a bottom of the first trench, the second conductivity type floating region having a high impurity concentration; and a second conductivity type base region disposed below or at a bottom of each of the second trenches, wherein each gap between said second conductivity type base region and said second conductivity type floating region has a wide portion and a narrow portion.