Lanthanum gallate substrates for epitaxial highhyphen;temperature superconducting thin films

摘要

We demonstrate that lanthanum gallate (LaGaO3) has considerable potential as an electronic substrate material for highhyphen;temperature superconducting films. It provides a good lattice and thermal expansion match to YBa2Cu3O7minus;x, can be grown in large crystal sizes, is compatible with highhyphen;temperature film processing, and has a reasonably low dielectric constant (egr;bartil;25) and low dielectric losses. Epitaxial YBa2Cu3O7minus;xfilms grown on LaGaO3singlehyphen;crystal substrates by three techniques have zero resistance between 87 and 91 K.