Stable preparation process of superconductor-insulator multilayer films for HTS devices by off-axis magnetron sputtering

摘要

The preparation process for epitaxial multilayer films consisting of Y0.9La0.2Ba1.9Cu3Oy (La-YBCO) and SrSnO3 (SSO) for high-T-c superconductor (HTS) electronic devices was developed. Four-layer films of SSO/La-YBCO/SSO/La-YBCO were deposited on BaZrO3-buffered MgO(100) substrates by off-axis magnetron sputtering. During deposition, the substrates were directly heated from backside by thermal radiation of a heater. No adhesive paste, such as Ag, for fixing the substrate was used in order to avoid contamination. Deposition conditions, especially the heater temperature profiles and atmosphere during elevating the temperature, were carefully controlled. The multilayer films with the average surface roughness R-a around 2.0 nm were prepared with high reproducibility. Continuous production of the high-quality films throughout one year proved excellent stability of the preparation process. (c) 2006 Elsevier B.V. All rights reserved.