Molecular beam deposition and characterization of thin organic films on metals for applications in organic electronics

摘要

The deposition of organic thin films on metal substrates using molecular beam deposition will be reviewed with a special emphasis on molecules which exhibit high charge carrier mobilities and arc thus suited to be used as organic semiconductors (OSCs), namely pentacene, rubrene and perylene. Special emphasis will be on aspects of organic molecular beam deposition (OMBD) relevant for the device performance in organic field effect transistors (OFETs), in particular with regard to avoiding or minimizing structural delects at support/ OSC interfaces. In addition, another aspect governing andrnoften limiting - charge injection at electrodes into an OSC, electronic level alignment at molecule/metal interfaces, will be discussed in the context of recent accurate ab-initio electronic structure calculations. Finally, we will present a novel experimental approach to determine charge transport properties of defect-free, nm-sized OSCs where extrinsic contributions to e.g. charge carrier mobilities can be strictly excluded, thus opening the way towards the determination of true intrinsic OSC properties.