Preparation of α-alumina/polymethacrylic acid composite abrasive and its CMP performance on glass substrate

Chemical mechanic polishing (CMP) has become a widely accepted global planarization technology. Abrasive is one of key elements during CMP process. α-Alumina particles, as a kind of widely used abrasive in CMP slurries, often cause surface defects due to its high hardness and agglomeration. In order to enhance the dispersion stability and prevent agglomeration of pure alumina abrasives in CMP, α-alumina grafted with polymethacrylic acid (α-Al2O3-g-PMAA) composite abrasives was prepared and characterized by means of Fourier transform infrared (FTIR), Mastersizer 2000 instrument and scanning electron microscope (SEM). The results indicated that the prepared α-Al2O3-g-PMAA composite abrasives have better dispersion stability than pure α-Al2O3 abrasives. The CMP performances of the α-Al2O3-g-PMAA composite abrasives on glass substrate were investigated by SPEEDFAM-16B-4M CMP equipment with different process parameters. By using the optimum process parameters, the prepared abrasives exhibit better glass substrate CMP performance than pure α-Al2O3 abrasives. Further, the CMP mechanism of glass substrate was deduced preliminarily.