Amorphous lithium lanthanum titanate thin films were prepared by pulsed laser deposition method. By X-ray diffraction measurement of the films, it was confirmed that the crystal structure of the as-prepared thin films was amorphous. The temperature dependence of the ionic conductivity of the amorphous thin film was measured from 300 to 475K over the frequency region 100Hz to 10MHz. The value 0.35eV was estimated as the activation energy of Li+ ionic conduction in the film at 300 to 475K. It was revealed that the transfer ratio of Li+ ion for the ionic conduction of the amorphous thin film was over 94%, and the amorphous thin film exhibited super-ionic conduction at and above room temperature. The conductivity of the thin film was an order of magnitude higher than that of its polycrystalline precursor, mainly due to absence of grain boundary elements and its structural disorder.

Ionic Conductivity of Amorphous Lithium Lanthanum Titanate Thin Film. S.Furusawa, H.Tabuchi, T.Sugiyama, S.Tao, J.T.S.Irvine: Solid State Ionics, 2005, 176[5-6], 553-8