Preparation and Properties of the Y-Ba-Cu-O Thin Films

Abstract

We investigated superconducting YBa₂Cu₃O_y (YBCO) thin films, which were prepared with two synthetic processes using rf-magnetron sputtering :(a)deposition at low substrate temperature with post-annealing at around 900°C and (b)deposition at high substrate temperature around 650°C with or without post-annealing. We obtained the high Tc superconducting YBCO thin films with each process.The films prepared with process(a) had, however, poor Jc below 10A/cm² at 77K and their surfaces were rough. On the other hand, the films prepared with process(b) had higher Jc and smoother surfaces than those with process(a). Further improvement in surface morphology was made by raising substrate temperature to 700°C at the start of the deposition.