SURFACE-EMITTING POLYMER LIGHT-EMITTING-DIODES

We report the fabrication of polymer electroluminescent devices on dop ed silicon substrates. An electron-injecting aluminium electrode is th ermally evaporated onto the silicon substrate, and a layer of a high e lectron affinity conjugated polymer, poly(cyanoterephthalylidene), CN- PPV, is then spin-coated onto this. A hole-transporting layer of poly( p-phenylene vinylene), PPV, is formed on top of the CN-PPV layer by th ermal conversion of a spin-coated layer of the sulphonium precursor po lymer. Finally, a transparent hole-injecting top electrode of indium-t in oxide is formed by RF sputtering. These devices show efficient red electroluminescence, with emission from the CN-PPV layer.