Electronic properties of interfaces between model organic semiconductors and metals

We present a summary of recent studies of the interface properties of interfaces that are formed between well-established molecular organic semiconductors and various metals. The energy level alignment, the formation of interface dipoles, a possible band bending and interactions at the interfaces have been investigated using photoemission spectroscopy, while polarization-dependent X-ray absorption spectroscopy provided information on the molecular orientation at the interfaces. The observed interface characteristics reach from physisorption to a reaction depending upon both the substrate and the organic molecule under investigation. Different contributions to the often observed interface dipoles are discussed. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.