Fast removal of surface damage layer from single crystal diamond by using chemical etching in molten KCl plus KOH solution

To fast remove the surface damage layer from single-crystal-diamond, we have developed a chemical etching process using molten KCl and KOH solution at high temperature around 1100 degrees C. High removal rate about R-{001} = 2.0 mu m/h, R-{101} = 20 mu m/h and R-{111} = 26 mu m/h was achieved for the {001} sample surfaces, {101} and 011 sample edges, respectively. Laser microscope observation has confirmed that the {001} surface flatness has been greatly improved after etching and surface roughness formed during previous lift-off process has been effectively removed. (C) 2015 Elsevier B.V. All rights reserved.