INITIAL-STAGE OF EPITAXIAL-GROWTH MECHANISM OF CADMIUM ARACHIDATE PREPARED BY PHYSICAL VAPOR-DEPOSITION ON VARIOUS SUBSTRATES

It is found that when it is deposited on a solid surface at 25-degrees-C at a pressure of 1 x 10(-8) Torr with a thickness less than 0.5 nm, cadmium arachidate forms a molecular aggregate with a diameter of 100-500 nm. In these aggregations, the long chain molecules make an orientation with the chain axes normal to the substrate surface. Just after nucleation occurs, the molecular aggregates seem to be of a meta-stable state and subsequently transform to stable crystalline phases of slender or planar shapes depending on the kinds of substrate. On the KCl substrate, needle-like crystals are generated to grow along two directions corresponding to the [110] axes of KCl. The planar crystals on mica show the periphery parallel to each other, while those on carbon film have no correlation. These results exhibit that the long chain molecules grow epitaxially on the KCl (mica) substrate with parallel (normal) molecular orientations.