Patent ID: 8350322
Filing Date: 2013-01-08
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a first semiconductor layer of a first conductivity type: a second semiconductor layer of the first conductivity type, provided on a first major surface of the first semiconductor layer; a third semiconductor layer of a second conductivity type, provided on the second semiconductor layer; a source region of the first conductivity type, provided on a surface of the third semiconductor layer; a first main electrode electrically connected to a second major surface of the first semiconductor layer; a second main electrode electrically connected to the source region; trench gates that partition a plurality of unit cells provided in a cell region where a main current flows in a vertical direction between the first main electrode and the second main electrode via the source region, and are provided so as to reach from the surface of the third semiconductor layer to the second semiconductor layer; a first contact region containing an impurity of the second conductivity type ion implanted at a bottom of each of a plurality of first contact holes formed in the third semiconductor layer at a central portion of each of the plurality of unit cells and electrically connecting the second main electrode and the third semiconductor layer; and a second contact region containing an impurity of the second conductivity type ion implanted at a bottom of each of a plurality of second contact holes formed in the third semiconductor layer in a termination region provided surrounding the cell region and electrically connecting the second main electrode and the third semiconductor layer, an opening area of each of the second contact holes being smaller than an opening area of each of the first contact holes.