Top-emitting organic light-emitting devices using surface-modified Ag anode

A high-reflectivity bottom anode is essential for high-performance top-emitting organic light-emitting devices (OLEDs). Ag has the highest reflectivity for visible light among all metals, yet its electronic properties are not ideal for anodes of OLEDs. In this letter, we report that by inducing a thin silver oxide at the surface of Ag, hole injection from Ag anodes into OLEDs is largely enhanced yet with rather high reflectivity retained. Top-emitting devices using such surface-modified Ag anode show device characteristics competitive with those of a bottom-emitting device using the indium tin oxide anode.