Patent ID: 9515197
Filing Date: 2016-12-06
CPC Classification: H01L

Claim Text:
1. A silicon carbide semiconductor device comprising a JFET, the JFET including: a semiconductor substrate including a first conductivity-type substrate made of silicon carbide, a drift layer of a first conductivity-type formed on the first conductivity-type substrate by epitaxial growth, a first gate region of a second conductivity-type formed on the drift layer by epitaxial growth, and a source region of the first conductivity-type formed on the first gate region by epitaxial growth or ion implantation; a trench penetrating the source region and the first gate region and reaching the drift layer, the trench having a strip shape including a longitudinal direction set in one direction; a channel layer of the first conductivity-type formed on an inner wall of the trench by epitaxial growth; a second gate region of the second conductivity-type formed on the channel layer; a first depressed portion formed at an end portion of the trench, the first depressed portion extending to a position deeper than a thickness of the source region by removal of the source region from the end portion of the trench; a second conductivity-type layer covering only a corner portion at a boundary between a bottom surface and a side surface of the first depressed portion; and the corner portion of the first depressed portion being filled with the second conductivity-type layer and having a rounded shape, wherein a second conductivity-type impurity concentration of the second conductivity-type layer is equal to or higher than 1×10