Highly efficient and stable inverted bottom-emission organic light emitting devices

The authors report the development of highly efficient and stable C545T doped green fluorescent Alq₃ inverted bottom-emission organic light emitting device (OLED), with a device configuration of ITO /Mg/Cs₂O:Bphen/Alq₃/C545T:Alq₃/NPB/WO₃/Al, that achieved a maximum current efficiency of 23.7cd/A and a power efficiency of 12.4lm/W which are two times better than those of the conventional OLED. At a brightness level of 100cd/m², the device required driving current density only as low as 0.5mA/cm² at a driving voltage of only 5.0V and its half-lifetime T_1/2 in excess of 104000h.