POLISHING AGENT AND POLISHING METHOD

摘要

A non-oxide single crystal substrate such as a silicon carbide single crystal substrate is polished at high polishing rate, thereby obtaining a flat and smooth surface. Provided is a polishing agent which contains: an oxidant that contains a transition metal and has a redox potential of 0.5 V or more; silica particles that have an average secondary particle diameter of 0.2 mum or less; and a dispersion medium. The content of the oxidant is from 0.25% by mass to 5% by mass (inclusive), and the content of the silica particles is 0.01% by mass or more but less than 20% by mass.