Supramolecular Order of Solution-Processed Perylenediimide Thin Films: High-Performance Small-Channel n-Type Organic Transistors

Abstract

N,N ′ -1 H ,1 H -perfl uorobutyl dicyanoperylenecarboxydiimide (PDIF-CN 2 ), a soluble and air stable n-type molecule, undergoes signifi cant reorganization upon thermal annealing after solution deposition on several substrates with different surface energies. Interestingly, this system exhibits an exceptional edge-on orientation regardless of the substrate chemistry. This preferential orientation is rationalized in terms of strong intermolecular interactions between the PDIF-CN 2 molecules. The presence of a pronounced π– π stacking is confi rmed by combining near-edge X-ray absorption fi ne structure spectroscopy (NEXAFS), dynamic scanning force microscopy (SFM) and surface energy measurements. The remarkable charge carrier mobility measured in fi eld-effect transistors, using both bottom- and top-contact (bottom-gate) confi gurations, underlines the importance of strong intermolecular interactions for the realization of high performing devices.