Published online by Cambridge University Press: 01 February 2011
Indium gallium zinc oxide (IGZO) has attracted recent attention as a high electron mobility amorphous material for high performance thin film transistors and subsequent use in active matrix backplanes for flexible displays. In this study, Eu:IGZO thin films were pulsed laser deposited at room temperature onto sapphire substrates and were investigated by cathodoluminescence and optical transmission. Photoluminescence was not observed with above band gap excitation. Thin film electroluminescent (TFEL) devices were also fabricated from these thin films. The thin films and devices demonstrate characteristic europium emission, with the most intense emission at 611 nm corresponding to the 5D0 to 7F2 transition. Luminescence was observed to increase with increasing oxygen pressure during deposition of the Eu:IGZO thin films and may be related to the free carrier density in the films. The authors believe this to be the first report of an amorphous oxide electroluminescent phosphor.