Energy Level Alignment of Indium Tin Oxide/Pentacene/C₆₀

Organic - heterojunctions are widely utilized in exciton dissociation and charge-generation layers in optoelectronic devices.In these applications, the energy difference between the highest occupied molecular orbital (HOMO) of a -type organic semiconductor and the lowest unoccupied molecular orbital (LUMO) of an -type organic semiconductor (HOMO -LUMO ) significantly affects device performance.Therefore, determining the energy-level alignment of an organic - junction is important.In this study, the energy-level alignment of indium tin oxide/pentacene/C 60 interfaces was investigated using in-situ ultraviolet and X-ray photoelectron spectroscopy measurements.Type II alignment and significant band bending were observed at the pentacene/C 60 interface.The HOMO -LUMO was measured to be 0.97 eV, similar to reported values.The HOMO -LUMO was not significantly affected by the substrate work function when the pentacene layer thickness was sufficient.These results are important for the design of efficient organic device architectures.