Influence of Thickness of the Carriers Transport Layer On the EL Properties in Organic Thin Film Electroluminescence

Three organic thin film electroluminescence devices (OELD) with different thickness of carriers transport layer: 30nm, 60nm, 120nm and the same thickness of luminescent layer: 300nm, were prepared. The OELDs were the double layer structure of ITO/PVK/Alq/Al. On the basis of a model for generation transport and recombination of carriers and for carrier arbitrary hopping model in organic light emitting devices, a complete analytic function for exciton fission and recombination and for densities distribution of electron and hole are proposed, comparing and analyzing their EL spectra andJ-Vproperties, it is found that the thickness of carrier transport layer influences the brightness, current density and onset volt of EL devices. The theoretical results are in agreement with the experimental values satisfactorily.