Evaluation of surfaces of single SiC crystal polished with various kinds of particles

Si-terminated surfaces of single SiC crystal were polished by the mechano-chemical polishing method using various kinds of particles. Polished surfaces were evaluated by FT-IR and XPS in order to investigate the polishing mechanism. The stock removal rate of the Si-terminated surface was increased and stabilized by adding Cr₂O₃ free abrasive to the Cr₂O₃ polishing disk during polishing. Si add-atoms were formed on the surface polished with the Cr₂O₃ abrasive. These were removed by a subsequent polishing process with BaCO₃ particles which have the ability to cut the Si-Si bonds. The TiO₂ photo-catalyst, which has a strong oxidizing ability through photon energy absorption, was applied to polish the SiC surfaces. Since the silicon oxide film was formed and TiO₂ adsorbed, a slow stock removal rate was obtained. However, it was found that the TiO₂ photo-catalyst is effective for the SiC mechano-chemical polishing by a follow-up polishing with CeO₂ particles.