We present electroabsorption (EA) technique measurements of internal electric fields in poly(9,9'-dioctylfluorene)(PFO)-based multilayer polymer light-emitting diodes (PLEDs) with and without an interfacial layer between the hole conducting layer and the emissive layer. There is a strong internal electric field screening effect for the interfacial material-based PLEDs, which can explain the significant improvement of the device efficiency caused by adding a 10nm layer of poly(9,9-dioctyl-fluorene-co-N-(4-butylphenyl)- diphenylamine) (TFB) between a poly(styrene sulphonate)-doped poly(3,4-ethylene dioxythiophene) (PEDOT:PSS) layer and a PFO emissive layer.
|Original language||English (US)|
|Title of host publication||IDW '06 - Proceedings of the 13th International Display Workshops|
|State||Published - Dec 1 2006|