Easily controlled dye doped phosphorescent OLEDs with evaporation rate in single furnace

Electrical and optical characteristic, surface morphology and energy transfer of Ir(ppy)3:PtTPP were studied as a function of thermal evaporation rate. We have investigated the effect of various evaporation rates for mixture of dyes using single furnace method. When the deposition rate increased from 0.5 to 5 Ǻ/s, the luminescence efficiency, current density and energy transfer of OLED increased. AFM measurements showed that the surface roughness of the Ir(ppy)3:PtTPP films decreased with increasing deposition rates. These blends show excellent red emitting guest-host system with easier deposition rate control.