Magnetic Characteristics and Ionic Conductivity

Recently Ishihara et al. [175] fabricated thin films of LaGeOs as a new oxide ionic conductor, on dense polycrystalline Al,0, substrates by a pulsed laser deposition (PLD) method and studied the effect of the film thickness on the oxide ionic conductivity on the nanoscale. The effective deposition parameters were optimized to obtain LaGeos thin films with stoichiometric composition. Annealing was found necessary to get crystalline LaGeo, thin films. It was also found that the annealed LaGeOs film exhibited extraordinarily high oxide ionic conductivity. Due to the nano-size effects, the oxide ion conductivity of Lasi Geo, thin films increased with the decreasing thickness as compared to that in bulk La, sGeOs4. In particular, the improvement in conductivity of the film at low temperature was significant.The electrical conductivity of the La, sGeOsa film with a thickness of 373 nm is as high as 0.05 S.cm' (log (r/S cm") = -1.3) at 573ºK.