Effect of 3-mercaptopropyltrimethoxysilane on Surface Finish and Material Removal Rate in Chemical Mechanical Polishing

Chemical Mechanical Polishing (CMP) is used in polishing of glass and ceramic surfaces as well as in integrated circuit manufacturing to remove excess material and provide a globally planarized wafer surface. One of the critical consumables in the CMP process is abrasive slurry typically containing both abrasives and chemicals acting together. To improve the chemical mechanical polishing performance, abrasive particles of acidic, basic and neutral colloidal silica were modified with 3-mercapto propyl tri methoxysilane (MPTMS) through silanization reaction with surface hydroxyl group. The modified abrasive slurries were used for chemical mechanical polishing of glass substrate. The results obtained indicate that the modified colloidal silica nanoparticlesslurry (MPTMS + Acidic Colloidal silica)with better dispersibility and stability in aqueous fluids resulted in improved surface finish and material removal rate than conventional process. The results of comparative study between three modified slurries showed that modified resulted (MPTMS + Acidic Colloidal silica) has better surface finish and more material removal rate of 6micron in four hours with surface finish in the range of 0.4 nm -0.7 nm, which proved to be better than the conventional process.