Preparation of solid electrolyte Ta-substituted Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub> epitaxial thin film using LiOH-flux liquid phase epitaxy

Solid electrolyte Ta-substituted Li7La3Zr2O12 (LLZTO) epitaxial thin films were grown using LiOH-flux liquid phase epitaxy at 600 C under the flow of N2 and H2O vapor mixture.Prior to the liquid phase epitaxy, amorphous La-Zr-Ta-O thin films were deposited on garnet-type Ga3Gd5O12 (GGG) substrates by dynamic aurora pulsed laser deposition for the thickness limitation and uniform film formation.Obtained thin films after liquid phase epitaxy, include Li content by x-ray photoemission spectroscopy.The epitaxial growth of LLZTO thin films on GGG (001), ( 110) and ( 111) substrates were confirmed by pole figures.The thin films had relatively low out-of-plane orientation degree despite liquid phase method.The surface observation reveals that the thin film surfaces consist of radially spreading regions with about 5-20 m, which implies that the growth condition in this study was at higher supersaturation degree.