The semiconductor device includes a semiconductor layer in which a via hole penetrating an upper surface of the semiconductor layer to a lower surface of the semiconductor layer is provided. The semiconductor device includes a first insulating film provided over the lower surface of the semiconductor layer and an inner surface of the via hole. The semiconductor device includes a second insulating film provided over the lower surface of the semiconductor layer and the inner surface of the via hole with the first insulating film interposed between the second insulating film and the semiconductor layer. The semiconductor device includes a device layer including a semiconductor element and provided on the side of the upper surface of the semiconductor layer.