Fabrication of YBa₂Cu₃O_y Thin Films on Textured Buffer Layers grown by Plasma Beam Assisted Deposition

Abstract

A new technique named plasma beam assisted deposition (PBAD) is proposed to grow in-plane textured yttria-stabilised zirconia (YSZ) thin films on polycrystalline metallic substrates as a buffer layer for deposition of YBa₂Cu₃O_y (YBCO) films. The in-plane texturing of the YBCO films obtained is decisively governed by that of the YSZ buffer layer on which the YBCO grows. Because of a reduction of the weak links at high-angle grain boundaries, a marked increase in the critical current density J_c is observed with improved texturing of the YBCO films. So far, it has been demonstrated that YBCO films with J_c above 10⁵ A cm^-2 (77 K, 0 T) can be successfully deposited by a laser ablation technique. The PBAD process proposed here is found to be valuable technologically because it offers a very convenient method to grow textured films on long tape or large area substrates. An attempt was also made to grow textured films simultaneously on one side or both sides of various pieces of tape substrates. The results indicate that PBAD is one potential technique for future large scale application of YBCO films.