A passivation film having a predetermined width from an outer peripheral end portion toward an inner side and extending along the outer peripheral end portion is formed on a front surface of a semiconductor substrate. An outer peripheral end surface orthogonal to the front surface and a rear surface is formed by grinding the outer peripheral end portion of the semiconductor substrate. A thickness of the semiconductor substrate is reduced to a predetermined thickness by grinding the rear surface. The ground rear surface is etched by discharging a mixed acid onto the rear surface while rotating the semiconductor substrate with the rear surface facing upward, to remove a fracture layer. Thereby, chipping or cracking of the semiconductor substrate is suppressed.