The interaction of C 60 with Si(111) and Co/Si(111)

Abstract

We have studied the interaction of C 60 with clean Si(111) and sub-monolayer Co covered Si(111) using scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). Our STM results indicate that C 60 has little mobility at room temperature (RT) on Co/Si(111). After annealing to 450°C, STM images show a regular arrangement of partially decomposed C 60-. XPS reveals a partial decomposition of C 60 on Co/Si(111) at 520°C, and total decomposition to form a SiC-3×3 phase at 720°C. These results show that Co catalyses C 60 decomposition resulting in the formation of the ordered SiC-3×3 phase ∼200°C below that on clean Si(111).