Optical properties of aluminumquinoline-oxadiazole codeposited luminescentlayers

Aluminumquinoline-oxadiazole (Alq(3)-PBD) codeposited layers, where the het erojunction of Alq(3) and PBD is expected to possess type-I energy lineup, were fabricated by vacuum evaporation, and their optical properties were in vestigated. The results showed effective energy transfer from PBD to Alq(3) followed by dominant emission from Alq(3), even at the Alq(3) concentratio n as low as about 1.5%. By using the Alq(3)-PBD codeposited layer as the em itting layer of electroluminescence (EL) devices, a successful increase in output power and quantum efficiency was observed compared to conventional E L structures.