Atomic Structure of Platinum Crystals Electrolytically Overgrown on Field-Ion Microscope Tips

Abstract

The platinum deposits overgrown on iridium and tungsten are polycrystalline with a crystal size of 50–500 Å. The orientation is mainly [111]. Some deposits on iridium grow epitaxially. A variety of defects, such as twinning, vacancy clusters, and high dislocation density (1011/cm2), are observed. Additionally, some experiments with copper deposits on iridium and tungsten are described. The corrosion of field-evaporated iridium tips both in air and in the plating solution is studied prior to the application of the electroplating.