Patent ID: 8796763
Filing Date: 2014-08-05
Classification: H01L

Abstract:
1. A semiconductor device comprising: a first conductivity type drain layer; a first conductivity type drift layer being formed above the drain layer, and having an impurity concentration lower than that in the drain layer; a second conductivity type channel layer located over the drift layer; a concave portion being formed in the channel layer, and having a lower end located below the channel layer; a gate insulating film formed on a side wall of the concave portion; a bottom surface insulating film formed on a bottom surface of the concave portion; a gate electrode buried in the concave portion; a first conductivity type source layer that is formed in the channel layer so as to be shallower than the channel layer, and that is located next to the concave portion when viewed from a plane; and a first conductivity type layer being located between the channel layer and the drift layer, and having an impurity concentration higher than that in the drift layer, wherein when viewed in a thickness direction, at least one of an upper end and a lower end of the first conductivity type layer, and a center thereof overlap with the bottom surface insulating film.