Development of damage-less mechanical polishing technique for hard to process materials using AC electric field

In the lapping process of single-crystal substrates for electronic devices such as SiC and sapphire, the damaged layer is formed on the surface of the substrate. The depth of this damaged layer affects the polishing time and cost of chemical mechanical polishing (CMP) process. In this study, we propose a novel mechanical polishing technology with low damage and high polishing efficiency by applying the resin pad and Electric Field assisted Polishing technology. In this report, it was confirmed that the depth of the altered layer formed can be reduced by about 0.16 times by using the resin pad, compared to the conventional lapping with a Cu platen. Furthermore, the effect of improving the polishing efficiency was confirmed by Electric Field assisted Polishing experiments on the large-scale polishing machine with a platen of 910 mm diameter, and the removal rate was about 1.5 times higher than that of conventional lapping process using Cu platen.