Possible new single-buffer layers for YBa2Cu3O7−y coated conductors prepared by chemical solution deposition

Abstract

New single-buffer layers of YBiO3 and SmBiO3 have been proposed for YBa2Cu3O7−y (YBCO) and SmBa2Cu3O7−y coated conductors. Highly c-axis oriented YBiO3 and SmBiO3 buffer layers have been deposited on single-crystal LaAlO3 and SrTiO3, respectively, by a low-cost chemical solution deposition method in a temperature range as low as 730 to 800 °C in air. Precursor solution of yttrium nitrate, samarium nitrate, and bismuth nitrate has been deposited using spin coating and heat treated in air in a single stage to yield textured YBiO3 and SmBiO3 buffers. A very dense, smooth, pinhole-free, and crack-free morphology has been observed for both buffers. Dense, homogeneous, and epitaxially grown YBCO film with thickness about 300 nm has been obtained on YBiO3 buffer with onset critical temperature 90 K and Jc (77 K, self-field) over 3 MA/cm2. These results offer an effective alternative to prepare desirable -buffer layer(s) for YBCO-coated conductors.