A fabrication process for semiconductor device, aimed to retard cracking in the lower surface of a silicon substrate subjected to grinding. A silicon substrate 1 is ground appropriately on the lower surface side. Consequently, fine and acute protrusions and recesses (crystal destruction layer of silicon) are formed on the lower surface of the silicon substrate 1. The lower surface of the silicon substrate 1 is then roughened with level difference of 1-5 [mu]m by wet etching. Subsequently, a protective film 12 is formed of epoxy based resin, or the like, on the lower surface of the silicon substrate 1. Since the lower surface of the silicon substrate 1 is roughened with level difference of 1-5 [mu]m, the rough surface is covered surely with the protective film 12 and cracking is retarded in the lower surface of the silicon substrate. |