Abstract
Organic electroluminescent devices consist of an organic layer or layers sandwiched between two electrodes. The transparent anode, which injects holes, is almost invariably Indium-Tin Oxide (ITO) coated glass, which has a high work function, and the cathode is a low work function metal capable of injecting electrons. Arrival of an electron and hole at the same molecule results in an excited state and the emission of visible light.
In this paper the structure and properties of multilayer devices are reviewed and possible models considered. Recent progress in controlling the work function of ITO by the introduction of self assembled monolayers of dipolar phosphonic acids, chemically bonded monolayers of dipolar silyl groups, and thin layers of electron acceptors is reported. The beneficial effects of these treatments, which can reduce the threshold voltage for light emission (turn-on) by 4V and increase the maximum luminescence by a factor of 3.5, are discussed.
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Willis, M.R., Day, S.R., Hatton, R.A. (2002). Organic Electroluminescent Devices Control of Carrier Injection. In: Graja, A., Bułka, B.R., Kajzar, F. (eds) Molecular Low Dimensional and Nanostructured Materials for Advanced Applications. NATO Science Series, vol 59. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-0349-0_2
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DOI: https://doi.org/10.1007/978-94-010-0349-0_2
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