To improve the yield of a method for polishing semiconductor device by reducing the number of foreign matters in polishing the semiconductor device by polishing the semiconductor device with a second polishing cloth having lower hardness lower than a firs polishing cloth has after the device is polished with the first polishing cloth, and then, only with pure water by using the second polishing cloth in polishing the device.

In polishing a semiconductor device by using a chemical mechanical polishing device, the semiconductor device is polished with a second polishing cloth having lower hardness than a first polishing cloth has after the device is polishing with the first polishing cloth, and then, only with pure water by using the second polishing cloth. The suitable polishing amount X and polishing pressure P with the second polishing cloth are 100 ≤X≤1,000 and 70 g/cm2≤P≤210 g/cm2, respectively, and the suitable polishing time T with the pure water is 10 sec≤T≤60 sec. The suitable hardness of the first and second polishing cloths are 60-95 (ASKER-C) and 20-70, respectively.