A method of manufacturing a semiconductor device having a back surface electrode, including: a step of preparing a semiconductor wafer having a front surface and a back surface; a thermal processing step of forming a first metal layer on the back surface of the semiconductor wafer and executing thermal processing, thereby creating an ohmic contact between the semiconductor wafer and the first metal layer; and a step of forming a second metal layer of Ni on the back surface of the semiconductor substrate after the thermal processing step.