Experimental Study on Electrochemically Assisted Friction and Wear of 4H-SiC Based on Advanced Oxidation Processes of Hydroxyl and Sulfate Radicals

Abstract

An electrochemical composite polishing technology based on advanced oxidation processes (AOPs) was proposed to achieve efficient polishing of SiC. In this study, ball-on-disk friction and wear experiments were carried out to study the tribological behavior of SiC under different polishing slurries (H2O, H2O2, and Na2S2O8). Our study found that the H2O2 and Na2S2O8 oxidation systems significantly enhance the material removal effect, and the average COF and wear-rate of SiC increase with the increase of the oxidizability of the environmental medium. The introduction of an electric field increases the wear-rates of the H2O2 and Na2S2O8 oxidation systems by more than 70%, which further improves the machinability of SiC wafers. When the chemical and mechanical actions are balanced, the coupling relationship between the two makes the material removal rate reach its maximum. The chemical mechanical polishing (CMP) results matched those of the friction and wear experiments. The results of this study provide theoretical support for the practical application of electrochemically assisted CMP slurry based on AOP oxidation systems.