A ReaxFF molecular dynamics study on the mechanism of material removal from 4H-SiC substrate in chemical mechanical polishing

A model of chemical mechanical polishing (CMP) is developed using the reaction force field molecular dynamics (ReaxFF-MD). Simulations are conducted on the chemical reactions and mechanical synergies of the 4H-SiC substrate in the CMP process, and material removal mechanism is analyzed. The results show that hydroxyl radicals from H
2
O
2
decomposition play a significant role in oxidation during the chemical reaction. The atoms on the substrate surface are removed as Si-OH, SiO
2
and CO
2
by chemical etching of the polishing solution and mechanical abrasion of the abrasive, which are carried away from the substrate surface with the abrasive movement.