Highly efficient polishing of single crystal diamond substrates using reactive species generated by triboelectric charging

This study developed a highly efficient polishing method for diamond substrates utilizing the reactive species generated by triboelectric charging under atmospheric conditions. In this technique, nitrogen or argon gas is introduced at the frictional interface between a diamond substrate and a synthetic quartz polishing plate, promoting the formation of reactive species, such as excited nitrogen and argon, near the contact area. These reactive species are subsequently employed to modify the surface of the diamond substrates. Experiments were conducted to clarify the impact of active species generated by triboelectric charging on diamond polishing. Luminescence measurements near the contact area between the diamond and the polishing plate confirmed the generation of excited nitrogen, excited argon, and OH radicals. The polishing efficiency could be improved several tens of times by simply supplying nitrogen or argon gas. The proposed approach is expected to enable high-efficiency diamond processing.