To provide a semiconductor device having high resistance against surge current.
A semiconductor device according to an embodiment comprises: a first conductivity type first semiconductor layer; a second conductivity type second semiconductor layer provided on a part of the first semiconductor layer; a first conductivity type third semiconductor layer and a second conductivity type fourth semiconductor layer having an effective impurity concentration higher than an effective impurity concentration of the second semiconductor layer, which are provided on a part of the second semiconductor layer and alternately arranged along a first direction; a gate insulation film provided on the second semiconductor layer; and a gate electrode provided on the gate insulation film. A resistance value between a boundary face with the first semiconductor layer and a boundary face with the third semiconductor layer, which is a resistance value of the second semiconductor layer in a second direction orthogonal to the first direction is larger than a resistance value between a position corresponding to a midpoint of the third semiconductor layer and a position corresponding to a midpoint of the fourth semiconductor layer, which is a resistance value of the second semiconductor layer in the first direction.
IKIMURA TAKEHITO
WATANABE KIMINORI
