Light outcoupling efficiency enhancement in organic light emitting diodes using an organic scattering layer

Crystallized 4,7-diphyenyl-1,10-phenanthroline (BPhen) films deposited by convenient vacuum thermal evaporation technique have been found to be an efficient means to extract the substrate wave guided light in organic light emitting diodes (OLEDs). The optimized BPhen film working as organic scattering layer was successfully used with OLEDs for light outcoupling efficiency improvement. Enhancement of 26%, 15% and 6% in efficiency of the blue, green and red OLEDs were obtained, respectively. The achievement was found to be advantageous in terms of simplicity of fabrication method and feasibility for large area OLED applications. ((c) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)