Chemisorption of C60 on the Si(001)-2 x 1 surface at room temperature

A synchrotron-radiation photoemission study Of C-60 deposited on a clean Si(001)-2 X 1 surface at room temperature is presented. It is found that the C-60 molecules are chemisorbed on the Si(001)2 X I surface with a characteristic of the covalent bond. A Si-C-60 hybridization causes charge transfer from the Si substrate to the C-60 molecules. Consequently, induced surface components appear in the Si 2p and C I s cores with opposite signs. To be specific for I monolayer coverage, two interface-induced Si 2p components are clearly resolved at the core-level shifts of +0.38 and +0.97 eV. For the C Is cores, in addition to a C-60-related peak at 284.50 eV, an induced peak shows up with a negative shift of -0.70 eV, suggesting that the carbon atoms hybridized with silicon surface atoms gain charge. (c) 2005 American Vacuum Society.