Sol-Gel Synthesis of GdAlO<sub>3</sub> Buffer Layers on SrTiO<sub>3</sub> (100) Substrates

Abstract

To identify the possibility of using GdAlO3 (GAO) as a buffer layer for YBa2Cu3O7-δ (YBCO) coated superconductor wire, we report the result of GAO deposition on SrTiO3 (STO) single crystal substrates by sol-gel processing. Precursor solution was prepared by dissolving stoichiometric quantities of gadolinium hexahydrate and aluminum isoproxide in a mixed binary solvent (2-4 pentanedione:methyl alcohol=1:1). The solutions were spin-coated on STO (100) single crystal substrates and heated at 500~1100 for 2 h in wet Ar-5% H2 atmosphere. A FESEM observation of the surface morphology of the GAO has shown that it has a very smooth surface with a faceted morphology indicating epitaxy. It was shown in x-ray diffraction characterization that epitaxial GAO films with epitaxial orientation relationship of (001)[112]GAO||(100)[110]STO have been grown on STO (100) substrates.