A semiconductor device includes a layer having first and second surfaces and a first type first region, a second type second region in the layer between the first region and first surface, a first type third region in the layer between the second region and first surface, first and second gate electrodes, wherein the second region is between the first and second gate electrodes, a first field plate electrode between the second surface and first gate electrode, a second field plate electrode between the second surface and second gate electrode, a first film, at least a portion between the first field plate electrode and first region, a second film at least a portion between the second field plate electrode and first region, and a second type fourth region in the first region between the first and second films. A portion of the first region is between second and fourth regions.