Tight-binding quantum chemical molecular dynamics simulation of mechano-chemical reactions during chemical-mechanical polishing process of SiO2 surface by CeO2 particle

Our tight-binding quantum chemical molecular dynamics method was applied to the investigations on the mechano-chemical reaction dynamics during the chemical-mechanical polishing (CMP) process of SiO2 surface by CeO2 particle. The mechanical forces introduced by the CeO2 particle were found to accelerate the chemical reactions at the CeO2-SiO2 interface. The time profile of the bond population and atomic charges reveals the mechanism of the mechano-chemical reaction dynamics during the CMP process. The electronic states change from Ce4+ to Ce3+ was observed during the CMP process and this reduction reaction is related to the specific characteristics of the Ce element, which has two oxidation states, Ce3+ and Ce4+. Finally, we concluded that our tight-binding quantum chemical molecular dynamics method is an effective tool to clarify the mechano-chemical reaction dynamics during the CMP process, because these investigations cannot be realized by the conventional first-principles calculation and classical molecular dynamics method. (c) 2004 Elsevier B.V. All rights reserved.