PURPOSE: To prevent chipping and to exclude a final organic washing step, by intentionally introducing edge drooping into an individual rectangular wafer.

CONSTITUTION: A semiconductor wafer, for which slicing lapping, etching and first mirror-surface polishing are performed, undergoes organic washing and rectangular cleaving, or rectangular cleaving and organic washing. Thereafter, second mirror-surface polishing is performed on the surface of the cleaved rectangular wafer. Finally the wafer is washed with water. Then, the mirror- surface polished rectangular semiconductor wafer, in which edge drooping is provided at the periphery of the upper surface and the edge drooping is not provided on the rear, is obtained. Thus chipping is prevented, and a final organic washing step is excluded.