Low-dimensional nanostructures and fullerene films on semiconductor surface

The morphology and atomic structures of C₆₀ fullerene films on a Bi(0001)/Si(111)-7 × 7 surface and adsorption of fluorofullerene C₆₀F _x molecules on a Si(111)-7 × 7 surface have been studied by scanning tunneling microscopy/spectroscopy and low-energy electron microscopy under ultra high-vacuum conditions. It has been shown that initial nucleation of C₆₀ islands on the surface of an epitaxial Bi film occurs on double steps and domain boundaries, while tunnel spectra do not exhibit any significant charge transfer to the lowest unoccupied molecular orbital states. Fluorofullerene molecules allow local (at the nanoscale level) modification of Si surface through local etching.