PURPOSE: To suppress a particle level in a surface by performing high speed polishing in a semiconductor wafer, and thereafter continuously performing a low speed polishing process, so as to maintain flatness of the semiconductor wafer surface in a high degree.
CONSTITUTION: A silicon wafer after an etching process is mounted in a platen 12, to use a prescribed polishing agent and liquid, so as to perform polishing by rotating, for instance, the platen 12 and a head 13 both at about 50rpm. Here is high increased a polishing rate in the beginning, to set a polishing margin to 15μm or less, and high speed polishing thereafter, the polishing rate is lowered to perform a low speed polishing process. As a result, high flatness of a wafer surface can be obtained, and also generating a particle due to polishing in this surface can be suppressed.
OKUTO SUSUMU
TANAKA MASAKI
TAKAISHI KAZUNARI
MITSUBISHI MATERIALS CORP