Surface topography and dielectric properties of polished PMN-PT single crystals

PMN-PT single crystals were polished to a roughness of 1 nm Sa and etched as well as heat-treated. The surface topography and dielectric properties of the samples were measured by various methods. The surface has an uneven structure with the appearance of fingerprints owing to the domain structure of the surface. A domain with positive polarity has a higher removal rate than one with negative polarity. The polishing rate strongly depends on the pH of the polishing fluid. The dielectric constant decreases with decreasing thickness of the polished sample, although such a decrease may be recovered by suitable heat treatment. (C) 2016 CIRP.