Transparent Organic Light-Emitting Devices Fabricated by Cs-Incorporated RF Magnetron Sputtering Deposition

For the cathode of a transparent organic light-emitting device (TOLED), an indium–tin oxide (ITO) film was deposited using RF magnetron sputtering with Cs vapor introduction during the sputtering process. The work function of the Cs incorporated ITO film was 4.3 eV with electric conductivity and it was very stable in an atmospheric environment over an extended period of time. It was shown that this Cs incorporation technique was effective for the incorporation of Cs in an ITO film and that it resulted in an ITO film with a low work function. The TOLED fabricated with ITO:Cs as a cathode showed a much higher electron injection efficiency than currently used devices with an alkali-metal doped organic layer at low current density.