Nanoscale Control of Layer Thickness for EL Devices by Mass-controlled Layer-by-layer Sequential Adsorption Process

Abstract

ABSTRACTA mass controlled layer-by-layer sequenitial adsorption process for polyelectlrolytes was newly developed for the fabrication of functional devices using ultra-thin organic film formed by various polymers of different polarity of charge. In this study hydrophobic Ruthenium complex monomer • tris(bipyridyl) ruthenium(II) hexafluorophosphate • was micelle-wrapped with an anionic surfactant, sodium dodecylbenzenesulfonate, and was assembled with PAH (poly (allylamine hydrochloride)), which has the opposite charge, on ITO substrates. With this method, we succeeded in fabricating ultra-thin organic films even when the adsorption material is not polymer but monomer. Moreover it was found that the film thickness of the self-assembled Ru micelle/PAH had a linear relationship with the number of bilayers. By using this process, an EL device was fabricated by depositing the thin film of micelle-wrapping ruthenium complex monomer on ITO and metal electrode on top of the film. Light emission was observed by applying voltage to this device.