Transparent conducting metal electrode for top emission organic light-emitting devices: Ca–Ag double layer

We have fabricated a transparent conducting double-layer metal electrode for top emission organic light-emitting devices which consists of thin layers of Ca and Ag metals of different thicknesses, deposited by the vacuum evaporation technique. The process is clean and does not damage the underlaying organic layers. High optical transparency over 70%, low reflectivity (14%) in the visible region, and low electrical sheet resistance (12 ohms/square) in Ca(10 nm)–Ag(10 nm) structures are reported. This transparent conducting Ca–Ag metal electrode opens a practical way to fabricate top-emitting organic displays without generating damage-induced states.