Polymer-assisted chemical solution deposition of high-quality La 2 Zr 2 O 7 buffer layer applied to low-cost YBCO-coated conductors

Abstract

Through a simple and low-cost way to gain the precursor solution, high-quality La₂Zr₂O₇ (LZO) buffer layers approximately 300 nm thick only by one single coating were successfully deposited on the textured Ni-5at%W alloy substrates using an independently developed new method of polymer-assisted chemical solution deposition (PA-CSD) with and without Y₂O₃ seed layer. Highly epitaxial YBa₂Cu₃O_7−x (YBCO) thin film with thickness of 500 nm is managed to be deposited on LZO/Y₂O₃/NiW. A study was made on the buffers and YBCO films with XRD, AFM, FIB-SEM, ESEM, and through superconducting critical temperature (T_c) analyses, and it was found that the Y₂O₃ seed layer had a good effect in improving the c-axis texture for the performance of LZO thin films. More importantly, the value of the self-field critical current density (J_c) of YBCO film on LZO/Y₂O₃/NiW architecture was 1.6 MA/cm² at 77 K. Our results indicated that the low-cost and effective way to develop high-performance YBCO-coated conductors on the basis of high-quality LZO buffer layer were suitable candidates.