The influence of LiF thickness on the built-in potential of blue polymer light-emitting diodes with LiF/Al cathodes

Autor: Thomas M. Brown, D. J. Lacey, Richard H. Friend, Franco Cacialli, J. H. Burroughes, I. S. Millard
Rok vydání: 2001
Předmět:
Zdroj: Synthetic Metals. 124:15-17
ISSN: 0379-6779
DOI: 10.1016/s0379-6779(01)00412-x
Popis: We use electroabsorption to investigate the built-in potential of polymer light-emitting diodes with LiF/Al cathodes, as a function of the LiF thickness d . We find that the built-in potential increases with d , reaching a plateau at d ≤7 nm. The results, obtained on finished devices, imply a correspondent lowering of the cathode work function, which correlates with the device luminance and efficiency. Consequently, we demonstrate that the improvement in device performance, brought about by the thin LiF layers, is predominantly attributable to the reduction of the barrier height to electron injection.
Databáze: OpenAIRE