Surface conductivity of ceria abrasives during glass polishing

Ceria-based abrasives show high removal rates on glass polishing owing to chemical mechanical polishing (CMP). The role of chemistry in CMP still remains vague, but redox reaction of Ce⁴⁺/Ce³⁺ would play a major role for softening glass surface. Oxidation-reduction potential of the redox reaction would be an index of chemical polishing, but there are few data that exhibit electrical or electrochemical properties during polishing. We then investigate electrical conductivity at the interface among glass, water and ceria abrasives during polishing. The interfacial area specific resistance was decreased with increasing rotation rate during glass polishing. Electronic charge carrier in the vicinity of interface between ceria abrasive and water solution was transferred by polishing and this indicates that the redox reaction would occur during glass polishing.