Thickness Effect on the Structural and Electrical Properties of Sputtered YBCO Coated Conductors

In this paper we studied the structural and electrical properties variations with the thickness of YBa₂Cu₃O_7-X (YBCO) film. In our experiments, the critical current density (Jc) has a maximum at 1.2 micron rather than monotonically decreased with increasing film thickness. The in-plane and out-plane alignments of the films, measured with X-ray Diffraction Omega-scan and Phi-scan, were poor at the beginning stage of the deposition and then became better as the film thickness increased.The surfaces of different samples also change a lot while films less than 700 nm in thickness. Under optimized deposition conditions, biaxial textured YBCO films have been obtained, with the full width at half maximum being 2.1° and 4.5° for out-of-plane and in-plane orientations respectively, Jc greater than 1.2 MA/cm² at 77 K, self field.