SEMICONDUCTOR DEVICE

Provided is a semiconductor device that has, mounted on a lead frame, a vertical semiconductor element which uses a Ga2O3-based semiconductor as the material of a substrate and epitaxial layer, the semiconductor device being capable of effectively releasing heat from the semiconductor device to the lead frame. As one embodiment, a semiconductor device 1 is provided which comprises: a lead frame 20 that has a projection 200 on the surface; and an SBD 10 that is mounted face down on the lead frame 20 and includes a substrate 11 which is made of a Ga2O3-based semiconductor, an epitaxial layer 12 which is stacked on the substrate 11 and made of the Ga2O3-based semiconductor, a cathode electrode 13 which is connected to the substrate 11, and an anode electrode 14 which is connected to the epitaxial layer 12 and has a field plate part 140 on an outer peripheral part. The SBD 10 is fixed on the projection 200, and an outer peripheral part 120 of the epitaxial layer 12 is located right above a flat part 201 of the lead frame 20.