SEMICONDUCTOR DEVICE

摘要

A semiconductor device includes a semiconductor layer made of a wide bandgap semiconductor and including a gate trench; a gate insulating film formed on the gate trench; and a gate electrode embedded in the gate trench to be opposed to the semiconductor layer through the gate insulating film. The semiconductor layer includes a first conductivity type source region; a second conductivity type body region; a first conductivity type drift region; a second conductivity type first breakdown voltage holding region; a source trench passing through the first conductivity type source region and the second conductivity type body region from the front surface and reaching a drain region; and a second conductivity type second breakdown voltage region selectively formed on an edge portion of the source trench where the sidewall and the bottom wall thereof intersect with each other in a parallel region of the source trench.

主权项

1. A semiconductor device comprising:
a semiconductor layer made of a wide bandgap semiconductor having a gate trench provided with a sidewall and a bottom wall; a gate insulating film formed on the sidewall and the bottom wall of the gate trench; and a gate electrode embedded in the gate trench to be opposed to the semiconductor layer through the gate insulating film, wherein the semiconductor layer includes: a first conductivity type source region formed to be exposed on the side of a front surface of the semiconductor layer for partially forming the sidewall of the gate trench; a second conductivity type body region formed on a side of the source region closer to a rear surface of the semiconductor layer to be in contact with the source region for partially forming the sidewall of the gate trench; a first conductivity type drift region formed on a side of the body region closer to the rear surface of the semiconductor layer to be in contact with the body region for forming the bottom wall of the gate trench; and a second conductivity type first breakdown voltage holding region selectively formed on an edge portion of the gate trench where the sidewall and the bottom wall intersect with each other in a partial region of the gate trench, wherein the drift region includes: a first region of a first impurity concentration forming the bottom wall of the gate trench; and a second region of a second impurity concentration smaller than the first impurity concentration formed on a side of the first region closer to the rear surface of the semiconductor layer to be in contact with the first region.