Microscopic Interaction Mechanism between Surfactants and SiO₂ Abrasives and Its Performance in Sapphire Polishing

In chemical mechanical polishing (CMP), the synergistic effects between surfactants and abrasive particles significantly influence material removal efficiency and surface quality. Through molecular dynamics simulations, we investigate how three surfactants—cationic CTAC, anionic K12, and nonionic AEO—interact with SiO 2 abrasives. The simulation results show that CTAC induces abrasive agglomeration through electrostatic attraction to enhance the material removal rate (MRR), making it suitable for polishing stages requiring high MRR. K12 maintains abrasive dispersion through electrostatic repulsion to reduce surface roughness, it can be combined with other surfactants to achieve a synergistic effect. AEO achieves a balance between efficiency and quality through hydrogen bonding networks, which is ideal for high-precision polishing prioritizing low roughness and stability. Finally, we conducted sapphire CMP experiments to validate the MD simulation conclusions by measuring MRR, roughness, contact angle, surface tension, and particle size. This work provides guidance for the selection of appropriate surfactant in future CMP processes.