X-ray and ultraviolet photoemission study of the formation and band lineup of C60/Si(111) interface

The interface formation and band lineup of the C60/Si(111) are studied using X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). It was found that there was no chemical reaction and diffusion between C60 overlayer and Si(111) substrate. The results showed that the C60/Si(111) interface was abrupt. According to the data of the core-level rigid shift and the top of the valence band, we obtained that the valence band offset ΔEv of C60/Si(111) heterojunction was equal to 0.40eV.