US Patent 11004931 Semiconductor device

According to an embodiment, a semiconductor device includes a semiconductor layer, a first electrode, and a first insulating film. The first electrode extends in a first direction and is provided inside the semiconductor layer. The first insulating film is provided between the semiconductor layer and the first electrode, a thickness of the first insulating film in a direction from the first electrode toward the semiconductor layer increasing in stages along the first direction. The first insulating film has three or more mutually-different thicknesses.