Patent ID: 9117903
Filing Date: 2015-08-25
Classification: H01L

Abstract:
1. A semiconductor device comprising: a first layer of a first conductivity type; a layer of a second conductivity type formed over the first layer of the first conductivity type; a second layer of the first conductivity type formed over the layer of the second conductivity type; a gate trench which passes through the second layer of the first conductivity type and the layer of the second conductivity type, and of which a lower end thereof reaches the first layer of the first conductivity type; a gate insulating film formed in an inner wall of the gate trench; a gate electrode buried in the gate trench; a buried layer of the second conductivity type formed in the first layer of the first conductivity type; a boundary insulating film located in a boundary between a lateral portion of the buried layer of the second conductivity type and the first layer of the first conductivity type; a lower layer of the second conductivity type, formed in the first layer of the first conductivity type, which is in contact with the buried layer of the second conductivity type and a lower end of the boundary insulating film; an electrode, formed at a higher position than the second layer of a first conductivity type, which is electrically connected to the buried layer of a second conductivity type; and a drain electrode formed under the first layer of the first conductivity type and electrically connected to the first layer of the first conductivity type.