Tansmission electron microscope Observation was made of the epitaxy of Bi deposited onto the surfaces of long-chain stearic acid molecular crystals, Vacuum-depositions of Bi onto stearic acid substrates, cleaved in air and vacuum, carried out at deposttion rates ranging 13Å/min to 3000Å/min. The residual gas pressures were 10
-6 Torr and 10
-4 Torr. The temprature of the substrate during deposition was 15°C. The epitaxy of Bi did not depond upon the lattice misfit between the substrate and the Bi thin film. The morphologies of Bi deposited onto the air-cleaved and vacuum-cleaved surfaces showed similar features at a film thickness ot about 100Å. There was also no significant difference in the epitaxial structures of Bi deposited in residual gas pressures of 10
-6Torr or 10
-4Torr. Typical morphology of the deposited Bi was observed to bc triangular and hexagonal-shaped islands. The number of the triangular shapes of Bi particles becomes larger as the deposition rate increases; the hexagonal shapes remarkably appeard as the deposition rate decreased. The three-dimensional shape of the triangular particles were those of trigonal pyramids, eud the hexagonal particles were found to be flat. The mechanism of Bi thin films on surfaces of molecular crystals has been discussed prviously.
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