@article{990d7ed8eff547a890cc8a81dab53dc6,
title = "Chemical and electronic aspects of metal/conjugated polymer interfaces. Implications for electronic devices",
abstract = "The chemical nature and the electronic structure of metal/conjugated polymer interfaces are investigated in the context of polymer-based light-emitting diodes. We consider the interaction of low-workfunction metals (Al, Ca) with the surface of conjugated polymers or model oligomer molecules with a combined experimental and theoretical approach. The early stages of the interface formation are followed with X-ray and ultraviolet photoelectron spectroscopies and the experimental data are compared to the results of quantum chemical calculations. The reactions of Al and Ca with the organic surface are found to be fundamentally different: while the former forms new covalent bonds onto the polymer backbone, the latter tends to dope the conjugated system. Both types of reaction are expected to modify drastically the electronic properties of the polymer semiconductor.",
author = "R. Lazzaroni and M. L{\"o}gdlund and A. Calderone and Br{\'e}das, {J. L.} and P. Dannetun and C. Fauquet and C. Fredriksson and S. Stafstr{\"o}m and Salaneck, {W. R.}",
note = "Funding Information: Even though both metals appear to modify strongly the electronic structure of the polymer, the consequences of the metal/polymer interactions on the electronic properties of the interface region could be very different. One one hand, the structure of the chain after Al bonding is reminiscent of segmented polyacetylene [ 181; the observed decrease in the x conjugation can be expected to reduce the mobility of charge carriers, hence to affect negatively the transport properties of the polymer layer close to the electrode. On the other hand, Ca deposition leads to the doping of the polymer at the interface; in principle. this should lead to increased conductivity in that region, which might favor charge transport across the moditicd layer. It could thus well be that the presence of the Ca-doped polymer region has a positive effect on the operation of the devices, Acknowledgements: Research on conjugated polymers in Mons is partly supported by the Belgian Prime Minister Office for Science Policy Programs “Pole d{\textquoteright}Attraction lnteruniversitaire en Chimie Supramoleculaire et Catalyse” and “Programme d{\textquoteright}lmpulsion en Technologie de I{\textquoteright}lnformation (contract SCiITi22)“. and by FNRS. The work in Linkoping is supported by grants from the Swedish Natural Sciences Research Council (NFR), the Swedish National Board for Industrial and Technical Development (NuTek). the Swedish Research Council for Engineering Sciences, and the Neste Corporation, Finland. The collaboration between Linkoping and Mons on metal/polymer interfaces is supported by the Commission of European Communittes SCIENCE program (Project 0661 POLYSURF).",
year = "1995",
month = apr,
day = "1",
doi = "10.1016/0379-6779(94)03203-I",
language = "English (US)",
volume = "71",
pages = "2159--2162",
journal = "Synthetic Metals",
issn = "0379-6779",
publisher = "Elsevier B.V.",
number = "1-3",
}