Time Dependence Of The Electronic Structure Of An Electron-beam-irradiated C_(60) Film

摘要

Time dependence of the electronic structure of an electron-beam (EB) irradiated C_(60) film (20-30 nm thick) has been examined using in situ high-resolution ultraviolet photoelectron spectroscopy. It is found that the electronic states of the C_(60) film have been changed continuously from an insulator (pristine C_(60) films) to a semiconductor and finally to a metal as EB-irradiation time increased. This can be explained by the increase in polymerization degree of a C_(60) polymer with a given cross-linked structure derived from the general Stone-Wales rearrangement from [Beu et al.,Phys. Rev. B 72, 155416 (2005)]. In addition, this finding suggests that the electronic properties of the C_(60) film can be controlled only in the EB-irradiated region by varying the irradiation time, which is interesting when applied to electronic devices.