Energy level diagrams of C 60/pentacene/Au and pentacene/C 60/Au

Abstract

The electronic structures of pentacene and C 60 interfaces were investigated using ultraviolet photoelectron spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS). The magnitudes of measured interface dipole were 0.11 eV and 0.07 eV for the C 60 deposited on pentacene (C 60/pentacene) and the pentacene deposited on C 60 (pentacene/C 60), respectively. The obtained C 1s spectra on these samples show that no significant chemical bonds at the interface. The offsets of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) at the C 60-pentacene interface were 1.29 eV and 0.89 eV for C 60/pentacene/Au, while for pentacene/C 60/Au they were 1.5 eV and 1.1 eV. In this paper we present the complete energy level diagrams of C 60/pentacene/Au and pentacene/C 60/Au.