| 摘要 |
According to one embodiment, a semiconductor device includes a semiconductor substrate including a drain layer of a first conductivity type and a base layer of a second conductivity type provided on the drain layer, a gate electrode including a first portion formed in the semiconductor substrate, a gate insulating layer provided between the gate electrode and the semiconductor substrate, an upper insulating layer formed on the gate electrode, a source layer of the first conductivity type that is provided on a sidewall of the upper insulating layer and whose width increases towards the base layer, and a source electrode provided on the source layer. |
