Using BCP layer to control the chroma of white phosphorescent organic light-emitting device

Abstract

Three types of double emitting layer white organic light-emitting devices (POLEDs) were fabricated. The efficiency of the device can be increased largely by the introduction of phosphorescent dye (Ir(ppy)3) and the chroma of the device can be tuned by inserting a BCP layer between the two light-emitting layers. The device with the configuration of: ITO/PVK:NPB (30nm)/BALq:3.0 wt%TBPe(30nm)/BCP(5.0nm)/CBP:5.0 wt%Ir(ppy)3:2.0 wt%rubrene(15nm)/BCP(10nm)/Mg:Ag shows white emission and high efficiency. A white light with Commission Internationale de l'Eclairage (CIE) coordinates of (0.31, 0.37) and brightness of 4670 cd/m2 are obtained at 17V. The device shows a maximum external efficiency of 1.4%. The CIE coordinates are well within the white-light region when the applied voltage varies between 5.0 to 17V.