Chemical-mechanically polishing large area free-standing CVD diamond films

摘要

Chemical mechanical polishing is used to polish large area free-standing CVD diamond films with diameters of 66 mm . The influence of polishing plates ( iron plate , asphalt plate and soft cushion) and oxidizing agents ( K2 S2 O8 and K2 FeO 4 ) on polishing results are investigated . Profilometer ( tip radius 5 μm) , optical microscope and Raman spectroscopy are used to evaluate the polishing effects of the CVD diamond films . Results show that the material removal rate of iron plate is the highest , while the surface polished by soft cushion is the most uniform with roughness of 2 nm . It is also found that the most effective oxidizing agent is K2 FeO 4 . In conclusion , the optimum polishing conditions are soft cushion and K2 FeO4 .