Silver/germanium/silver: an effective transparent electrode for flexible organic light-emitting devices

Mechanical resilience is important for future organic light-emitting devices (OLEDs) in lighting and displays. A key constraint is the electrode used in OLEDs. Here we demonstrate ultra-thin silver/germanium/silver (AGA)-based flexible organic light-emitting devices, with comparable efficiency to their ITO-based counterparts. The fabrication process of AGA electrodes is compatible with that of the OLEDs, and they show excellent optical, electrical and mechanical properties. They can be used as transparent cathodes and anodes for top-emitting, bottom-emitting and transparent flexible OLEDs.