A study on Ag nanowire electrode for organic light emitting diodes

Abstract

Silver nanowires (Ag NWs) networks are promising candidates to replace indium tin oxide as a transparent electrode of optoelectronic devices. However, the roughness of Ag NWs induced high leakage current and low efficiency of devices. In this work, we demonstrate simple and effective methods to reduce the surface roughness of Ag NWs with high optical transmittance (92 %) and low sheet resistance (30 ohm/sq). These properties are achieved by applying various pressure to the Ag NWs, by controlling NPB(HIL) thickness and by using MoO3 for super hydrophilic property. Using these methods, the surface roughness of Ag NWs electrode was reduced and the reverse leakage current (V= -5 V) of organic light emitting diodes (OLEDs) reduced from 101 mA/cm2 to 10-1 mA/cm2. Thus, the devices on Ag NWs results in an improvement of the luminance value by 18% compared to that from a conventional OLED on ITO substrates.