Effect of ingredients in slurry containing alumina on chemical mechanical polishing of hard disc substrates

Abstract

In this article, new slurry containing alumina abrasives, oxidants, and surface modifiers is developed for the primary polishing of Ni—P-plated hard disc substrates. Compared with commercial slurry, the developed one improves the surface quality drastically by relieving cold weld (CW) and scratch. A fairly high material removal rate (MRR) is obtained when the pH value of the slurry is 3.0. D50 (mean particle diameter) of the alumina abrasive is decreased by using a ball mill, which is effective in alleviating deep scratches and CW. Scanning electronic microscope and X-ray diffractometer are used to study the formation mechanism of CW. The oxidant hydrogen peroxide H2O2 is proved to be helpful in eliminating CW and improving the MRR largely. Lauroyl monoethanolamide sulfate C11H23CONHC2H4OSO3H as a surface modifier is added to the slurry to improve the surface quality further.