Abrasive-Free Polishing of SiC Wafer Utilizing Catalyst Surface Reaction

Catalyst-referred etching (CARE) is an abrasive-free chemical polishing method that utilizes a catalytic chemical reaction at the contact points of a wafer and a catalyst plate surface. Using a platinum plate catalyst and hydrogen fluoride aqueous solution, an atomically flat 4H–SiC (0001) wafer was obtained. The removal rate was found to be proportional to the rotational velocity and processing pressure, and it reached approximately 500 nm/h, which is comparable to chemical mechanical polishing methods. Furthermore, it was found that an atomically flat SiC surface can be obtained by CARE using only deionized water and a platinum catalyst, which is significant from the viewpoint of the widespread use of CARE.