Reproducible growth of high quality YBa2Cu3O7−x film on (100) MgO with a SrTiO3 buffer layer by pulsed laser deposition

Abstract
Epitaxial YBa2Cu3O7−x(YBCO) films were grown on SrTiO3‐buffered (100) MgO substrates by pulsed laser deposition. The SrTiO3 layer of about 500 Å thick serves a dual purpose to provide a better lattice match to the YBCO films as well as a diffusion barrier to prevent interaction between YBCO and MgO. These YBCO films exhibit excellent structural, electrical, and microwave properties with Tc≳89 K and Tc=2.9×106 A/cm2 at 77 K (1×106A/cm2 at 84 K). X‐ray pole figure measurements showed that over 99.92% of the volume fraction of the c‐axis oriented film has the ab axis aligned parallel to the [010] and [001] direction of the substrate.