Patent ID: 11888057
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A semiconductor device comprising:
a semiconductor substrate of a first conductivity type;
a drain electrode having ohmic contact with a lower face of the semiconductor substrate;
a drift layer of the first conductivity type formed on an upper face of the semiconductor substrate;
a well layer of a second conductivity type formed in part of an outermost layer of the drift layer;
a source layer of the first conductivity type formed in part of an outermost layer of the well layer and having a higher impurity concentration than that of the drift layer;
a first impurity layer of the second conductivity type formed in part of the outermost layer of the well layer and having a higher impurity concentration than that of the well layer; and
a source electrode formed in contact with the outermost layer of the drift layer in which the well layer is not formed, the well layer, the source layer, and the first impurity layer, wherein an interface at which the source electrode has Schottky contact with the drift layer is regarded as a Schottky interface, the first impurity layer and the Schottky interface sandwich the well layer therebetween, the first impurity layer is formed in the outermost layer of the well layer located closer to the Schottky interface than the source layer, to below and an inside of the well layer located farther from the Schottky interface than the source layer, and a lower face of the first impurity layer is located below the Schottky interface.