| 초록 |
Phosphorescent white organic light-emitting diodes (PHWOLEDs) were developed by using a carboline derivative as a host material doped with blue and orange phosphorescent dopants. Two different device architectures, two emitting layer device and co-doped device, were used to produce high efficiency PHWOLED. White emission color and high efficiency were obtained by controlling the thickness of blue and orange emitting layers or doping concentration of orange dopant. Two-emitting layer device showed an external quantum efficiency (EQE) of 16.3% and a current efficiency of 29 cd/A with a color coordinate of (0.26, 0.35) at a luminance of 1000 cd/m2. Co-doped device showed an EQE of 19.1% and a current efficiency of 35.2 cd/A with color coordinate of (0.36, 0.36) at 1000 cd/m2. |
