Patent ID: 9412819
Filing Date: 2016-08-09
CPC Classification: H01L

Claim Text:
1. A semiconductor device comprising: a substrate of a first conductivity type comprising silicon carbide; a drift layer of the first conductivity type formed over the main surface of the substrate; a first layer of the first conductivity type formed over the drift layer; a body layer of a second conductivity type, which is different from the first conductivity type, formed over the first layer; a source layer of the first conductivity type formed over the body layer; a trench formed so as to penetrate the source layer, the body layer, and the first layer and reach the drift layer; a channel layer of the second conductivity type formed in the body layer exposed at the sidewall part of the trench along the side surface of the trench; a second layer of the second conductivity type formed in the drift layer exposed at the bottom part of the trench along the bottom surface of the trench; a gate insulating film formed so as to cover the side surface and bottom surface of the trench; a gate electrode formed in the interior of the trench through the gate insulating film; source electrodes coupled electrically to the source layer and the body layer; and a drain electrode coupled electrically to the bottom surface on the other side of the main surface of the substrate, and wherein the impurity concentration of the first layer is higher than the impurity concentration of the drift layer and the impurity concentration of the channel layer and the impurity concentration of the channel layer is higher than the impurity concentration of the body layer.