A photoresist pattern is not formed in an outer circumferential region from an outer circumferential end of a semiconductor substrate up to 0.5 mm to 3.0 mm, in a process for patterning a silicon oxide film which will serve as a hard mask. A part of the silicon oxide film which is positioned in the outer circumferential region is removed, thereby exposing the semiconductor substrate, in a process for performing an etching process for patterning the silicon oxide film. In the process for performing the etching process for the semiconductor substrate with using the silicon oxide film as an etching mask, the surface of the semiconductor substrate of the outer circumferential region is lowered. Then, a step difference is formed in a position nearer to a chip formation region, in the semiconductor substrate.