Study of various evaporation rates of the mixture of Alq3: DCM in a single furnace crucible

The emitting color for a new organic light emitting diode (OLED) structure is tuned by doping an appropriate amount of 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) orange dye into tris-(8-hydroxyquinoline) aluminum (Alq3) emissive layer. Here, the blend of Alq3:DCM is deposited in a single furnace crucible by various evaporation rates. The electro-optical behavior of organic light emitting diode devices is greatly influenced by varying the Alq3:DCM film composition. It is investigated that when the deposition rate increased from 0.6 to 5 Å/s, complete energy transfer occurred from Alq3 to DCM and Electroluminescence (EL) peak shifted to higher wavelength regions. The device with evaporation rate of 0.6 Å/s shows a luminance of 3532 cd/m2 and maximum efficiency of 0.82 cd/A at 20 V. These blends show excellent orange emission host-guest system properties with easier deposition rate control.