Transparent Al/WO3/Au film as anode for high efficiency organic light-emitting diodes

A transparent Al/WO3/Au anode is introduced to fabricate high efficiency organic light-emitting devices (OLEDs). By optimizing the thicknesses of each layers of the Al/WO3/Au structure, the transmittance of Al(7 nm)/WO3(3 nm)/Au(13 nm) has reached over 55%. Concerning the performance of OLEDs using the optimized anode, the electroluminescence (EL) current efficiency and brightness are enhanced and the EL spectrum is greatly narrowed as compared to the OLEDs using indium-tin-oxide (ITO) as the anode. The results indicate that the metal/metal oxide/metal transparent electrode is a good structure for the anode of high performance OLEDs. In addition, Al/WO3/Au can function as a composite transparent electrode for top-emitting OLEDs.