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Silicon carbide (SiC) is regarded as a promising material in high power, high frequency and high temperature semiconducting devices, for its wide band gap, high electron mobility, high thermal conductivity, chemical inertness and hardness. Formation process of SiC upon annealing the Si(111) surface covered by C60 molecules with the thickness of 1.3 nm has been investigated by using synchrotron radiation photoelectron spectroscopy (SRPES) and X-ray photoemission (XPS) in NSRL. C60 molecules are chemisorbed on the Si(111) surface at room temperature, via Si-C60 hybridization to form covalent bonds, which can be explained by adsorption model including two adsorption configurations S3 and L. With annealing the sample, the Si-C60 hybridization weakened C-C bonds internally in C60 molecules and enhanced the formation of SixC60, an intermediate species. Further annealing the sample to 650¡æ will lead to the decomposition of C60 molecules, the released carbon fragment will bond with external silicon atoms to form SiC. Until annealing the sample to 850¡æ, decomposition of all C60 molecules was accomplished, and only a SiC film was left in the surface. |