Study on controlling mechanism of step-terrace structure in CeO2 slurry polishing of 4H-SiC

4H-SiC is considered one of the most promising next-generation semiconductor materials. Therefore, flattening methods of 4H-SiC and their mechanism have been widely studied in recent years. Although the generation of different types of step-terrace structure of 4H-SiC has been widely reported, their generation mechanism has not been thoroughly clarified. In this manuscript, the change of the surface atomic structure (step-terrace) structure of single-crystal silicon carbide (4H-SiC) along with the increasing of the pad rotation speed was confirmed. The generation mechanism of different types of step-terrace structure of 4H-SiC was proposed and experimentally clarified. We proved that the generation of different types of step-terrace structure of 4H-SiC could be controlled by adjusting the balance between chemical modification and physical removal in polishing.