Quinquethiophene light-emitting diodes with molecular dimensions

Abstract

Light-emitting diodes using Langmuir-Blodgett films of quinquethiophene as the emitting layer have been fabricated, and electrically and optically characterized. By utilizing additional layers of electron-transporting materials, the emitting material thickness has been reduced down to a single monolayer without serious decrease in the quantum efficiency. These electronic devices are valuable tools for studying carrier injection and transport, exciton formation, and quenching on a real molecular scale.