Fabrication and Analysis of Tri-layer YBa2Cu3 O (7-delta) Thick Films by Low-Fluorine MOD Method
Fabrication and Analysis of Tri-layer YBa2Cu3 O (7-delta) Thick Films by Low-Fluorine MOD Method
复制标题
低氟MOD法制备三层YBa2Cu3O(7-δ)厚膜并分析
DOI：
10.1007/s10948-017-4396-7
复制
发表时间：
2018
影响因子：
1.8
通讯作者：
Cai C. B.
中科院分区：
文献类型：
--
作者：
Shi C.;Liu Z. Y.;Liu X. M.;Hu X. F.;Li M. J.;Du W.;Bai C. Y.;Lu Y. M.;Guo Y. Q.;Cai C. B.
提高涂层导体中超导层的厚度是提高其临界电流的有效途径。本文采用多层低氟金属有机物分解（LF-MOD）法在缓冲Hastelloy基片上成功地制备了YBCO/YBCO/YDyBCO三层薄膜，薄膜厚度可达2.4μm。系统研究了高温退火时间对薄膜结构和超导性能的影响。能量色散X射线谱（EDS）结果表明，当退火时间过短时，在薄膜的上层仍有大量的F元素残留。随着退火时间的延长，含氟前驱体完全转变为YBCO晶粒。但退火时间过长，薄膜晶粒粗化，临界电流密度略有下降。利用扫描电子显微镜（SEM）和能谱仪（EDS）分析了YBCO薄膜的微观结构和元素分布。在最佳退火工艺条件下，YBCO超导薄膜的临界电流可达316 A（77 k，自场），带材宽度为1.2 cm。
Improving the thickness of superconducting layer in coated conductors is an effective way to enhance its critical current. In this work, tri-layer YBCO/YBCO/YDyBCO films were successfully deposited on buffered Hastelloy substrate using the multi-coating lowfluorine metal-organic decomposition (LF-MOD) method and the thickness of the films can be up to 2.4μm. The effects of high-temperature annealing time on microstructures and superconducting properties of the films were systematically studied. Energy dispersive X-ray spectroscopy (EDS) results reveal that there remains a large amount of F element in the upper layer of the film when the annealing time is too short. With increasing the annealing time, the fluoride-containing precursor converts to YBCO grains completely. But the coarsening of grains appeared, and the critical current density (Jc) of the film dropped slightly when the annealing time is too long. The cross-sectional scanning electron microscope (SEM) image and EDS plane analysis were applied to investigate the microstructure and element distribution of the final triple-layer YBCO films, respectively. The critical current of the final YBCO superconducting film could reach 316 A (77 k, self-field) for 1.2-cm-wide tapes with the optimal annealing conditions.