Inkjet-Printable Composite Electrode and Device Architectures for the Inverted Phosphorescent OLED

摘要

Composite electrode with fine line metallic grid was fabricated by ink-jet printing process. By the adjustment of the pitch of grid pattern, condition of 90-95% aperture ratio was applied for the production of semi-transparent electrode comparable with ITO. We have prepared the optimum composite electrode structure with metal grid/semi-conducting layer (such as poly(3,4-ethylene dioxythiophene): poly(styrenesulfonate) - PEDOT:PSS) for the normal and inverted organic light emitting diode (OLED). Luminous efficiency of 19.3 cd/A was obtained for green phosphorescent device, while the general performance of reference device on ITO are 20-23 cd/A. Inverted bottom and top emission OLEDs utilizing the metal grid composite electrodes were optimized, aiming for the adaptation on the flexible device architecture.