Abstract
By use of an etching solution of 70% by weight H2O, 22% K3[Fe(CN)6] and 8% KOH largely plane sample surfaces can be obtained, the quality of which corresponds to electrolytically polished metal surfaces. A possibly existing crystalline surface layer does not exceed a thickness of 25 Å. The method is suitable for preparing extremely thin samples, which are transparent for visible light and high energy electrons. X-ray investigations and electron micrographs indicate lattice defects of great concentration in the available monocrystals.