Study on low temperature processing for rare-earth-free high Tc superconducting thin films

Abstract

Thin flms of rare-earth-free high T c superconductors such as BiSrCaCuO and TlBaCaCuO systems have been prepared by RF-magnetron sputtering and subsequent annealing. These thin films showed a polycrystalline structure and had highly orientated c-axes perpendicular to the substrates. These thin films exhibited superconducting transitions above 100 K and critical current densities of more than 10 5 A cm −2 at 77 K, which was the same order of magnitude as the polycrystalline LnBaCuO thin films. This paper reports details of this fabrication process using XPS data, and discusses the possibility of low temperature preparation for rare-earth-free high T c superconductors.