A semiconductor device includes a multilayer substrate, a semiconductor element secured to an upper surface of the multilayer substrate, a first metal pattern located on a portion of a lower surface of the multilayer substrate, a dielectric having a higher permittivity than the multilayer substrate and located on the lower surface of the multilayer substrate, and a bottom surface electrode located on a bottom surface of the semiconductor device. The bottom surface electrode, the dielectric, and the first metal pattern together form a bypass capacitor.