High ionic conductivity of Na-βGa2O3 thin film.

Abstract

Sodium β-gallate thin films are prepared by rf sputtering and subsequent heat treatment. These thin films exhibit ionic conductivity as high as 4.2×10−2 Ω, cm−1 at 3000C and 7.0×10−6 Ω cm−1 at room temperature. Their ionic conductivity above 2000 C is only one order of magnitude less than that of single crystals. The activation energy of ionic conduction is 0.23 eV, that is, almost the same as that of single crystals. This ionic conductivity is high enough to be applied to thin-film devices of solid electrolytes.