Patent ID: 9577046
Date: 2017-02-21
CPC Classifications: H01L

Claim:
1. A semiconductor device comprising: a semiconductor layer having a first surface and a second surface and including an element region surrounded by a termination region; a first electrode on the first surface; a second electrode on the second surface; a first semiconductor region of a first conductivity type in the semiconductor layer, a portion of the first semiconductor region being in contact with the first electrode; a second semiconductor region of a second conductivity type in the element region of the semiconductor layer between the first semiconductor region and the first electrode; a third semiconductor region of the second conductivity type that is between the second semiconductor region and the first electrode, and is electrically coupled to the first electrode, an impurity concentration of the second conductive type in the third semiconductor region being higher than an impurity concentration of the second conductivity type in the second semiconductor region; and a fourth semiconductor region of the second conductivity type that is in the termination region of the semiconductor layer inwardly of the first surface, and is electrically coupled to the first electrode, wherein a distance between the fourth semiconductor region and the second surface is greater than a distance between the second semiconductor region and the second surface.