POLISHER LIFE IN ULTRA-SMOOTHNESS POLISHING OF MAGNETIC DISK SUBSTRATE USING NEW DOUBLE SIDE SURFACE POLISHING MACHINE

摘要

The main conclusions obtained are as follows: (1) The removal rate with polishing process changes in the four stages, which are the initial removal rate reducing stage, the steady removal rate stage, the later removal rate reducing stage and the extremely small removal rate stage corresponding to the life time. (2) The terminal surface roughness is at almost the same from the beginning of polishing to polisher life. (3) The polisher life occurs when the small hole on the polisher surface is mostly embedded by colloidal silica abrasives.