ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
Scanning tunneling microscopy (STM) was used to study morphological changes of a Pt thin film deposited on highly oriented pyrolytic graphite (HOPG) during an annealing process. In air, it was possible to image the morphology of the thin film with a vertical resolution of 0.5 Å and a lateral resolution of 20 Å. Surface structural change was observed after the annealing processes. When the annealing temperature was below 573 K, surface morphology changed only slightly. Between 573 and 873 K, the originally uniformly distributed rolling hills of Pt coagulated into larger clumps. Above 873 K, Pt crystal facets started to form on the surface. At 1123 K, a large portion of the surface turned into well defined Pt crystal facets. Above 1123 K, the Pt film started to crack and formed scattered crystals on the HOPG surface. A complementary X-ray diffraction measurement showed that the crystallized Pt film was preferentially oriented with the (111) plane parallel to the substrate graphite (0001) basal plane, indicating epitaxy of the Pt overlayer with the graphite substrate underneath.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108767390009060
Permalink
