title: Dithiocarbamate Self-Assembled Monolayers as Efficient Surface Modifiers for Low Work Function Noble Metals.
abstract: Tuning the work function of the electrode is one of the crucial steps to improve charge extraction in organic electronic devices. Here, we show that N,N-dialkyl dithiocarbamates (DTC) can be effectively employed to produce low work function noble metal electrodes. Work functions between 3.1 and 3.5 eV are observed for all metals investigated (Cu, Ag, and Au). Ultraviolet photoemission spectroscopy (UPS) reveals a maximum decrease in work function by 2.1 eV as compared to the bare metal surface. Electronic structure calculations elucidate how the complex interplay between intrinsic dipoles and dipoles induced by bond formation generates such large work function shifts. Subsequently, we quantify the improvement in contact resistance of organic thin film transistor devices with DTC coated source and drain electrodes. These findings demonstrate that DTC molecules can be employed as universal surface modifiers to produce stable electrodes for electron injection in high performance hybrid organic optoelectronics.
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Dominik
authors: D
authors: Meyer
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Tobias
authors: T
authors: Schäfer
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.|Department of Electrical Engineering, Princeton University , Princeton, New Jersey 08544, United States.|National Center for Photovoltaics, National Renewable Energy Laboratory , Golden, Colorado 80401, United States.
authors: Philip
authors: P
authors: Schulz
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Sebastian
authors: S
authors: Jung
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Julia
authors: J
authors: Rittich
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Daniel
authors: D
authors: Mokros
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Ingolf
authors: I
authors: Segger
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Franziska
authors: F
authors: Maercks
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Christian
authors: C
authors: Effertz
authors: Riccardo
authors: R
authors: Mazzarello
authors: I. Institute of Physics (IA), ‡Institute for Theoretical Solid State Physics, and §JARA-Fundamentals of Future Information Technology, RWTH Aachen University , 52056 Aachen, Germany.
authors: Matthias
authors: M
authors: Wuttig