POLISHING AGENT FOR SYNTHETIC QUARTZ GLASS SUBSTRATE, METHOD FOR MANUFACTURING THE POLISHING AGENT, AND METHOD FOR POLISHING SYNTHETIC QUARTZ GLASS SUBSTRATE

摘要

A polishing agent for a synthetic quartz glass substrate contains polishing particles and water. The polishing particles contain silica particles as base particles, and composite oxide particles of cerium and at least one rare earth element selected from trivalent rare earth elements other than cerium are supported on surfaces of the base particles. This provides a polishing agent for a synthetic quartz glass substrate, the polishing agent having high polishing rate and being capable of sufficiently reducing generation of defects due to polishing.