Effect of electric field on chemical mechanical polishing of langasite

The effect of dc electric fields on material removal rates of single crystal langasite during the chemical mechanical polishing process was investigated. The removal rate of the langasite in the commercial silica slurry was increased by up to 30% with a dc electric field ranging from −300 to +300 V/mm. The motion of slurry particles by surface charge was responsible for the electrical field-assisted chemical mechanical polishing (EFACMP) of langasite observed in this study. The effect of electric fields on chemical mechanical polishing is explained by the variation of the particle concentration due to the attraction to either the langasite surface or the pad by surface charge. The variation of the slurry particles near the langasite surface due to the electric field was confirmed experimentally by hardness variation in the slurry.