SiC formation on Si(100) via C60 precursors

The interaction between C60 molecules and the Si(100) surface and the preparation of silicon-carbide thin films by thermal reaction of C60 molecules with the Si(100) surface have been investigated using X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, reflection high-energy electron diffraction and atomic force microscopy measurements. The effects of annealing temperature and C60 coverage on the SiC formation will be discussed. It is found that the C60 molecules bond covalently with silicon, and the number of bonds increase upon increasing the annealing temperature. Annealing at T≥830°C entails the formation of stoichiometric silicon carbide clusters that coalesce to form a continuous SiC layer when the C60 coverage is greater than one monolayer. Deep pits acting as silicon diffusion channels are present with dimensions that increase with the amounts of C60. teraction of C60 with the SiC surface was also investigated. It is found that a similar covalent interaction is present in the two systems C60/Si and C60/SiC.