【作者】 张彦兵；

【导师】 赵勇；

【作者基本信息】 西南交通大学 ， 电工理论与新技术， 2007， 硕士

【摘要】 YBCO高温超导薄膜在军事、医学及电子等众多领域有非常广阔的应用前景，目前制备这种薄膜的主要方法有磁控溅射、激光脉冲沉积等。本论文旨在采用无氟MOD法制得具有钙钛矿结构的致密YBCO薄膜。以无机盐为初始原料研究了溶胶形成过程中的化学反应及成膜机理，探讨了LaALO₃基板上薄膜沉积技术等。进一步用X射线衍射仪和扫描电镜研究了薄膜结构、结晶情况和表面形貌，分析了衬底对YBCO薄膜制备的影响、以及不同热处理条件对薄膜结晶结构、形貌及性能的影响。研究结果如下：（1）采用钇、钡、铜的无机盐Y₂O₃，BaCO₃，CuO作出发原料，络合剂采用聚乙烯醇缩丁醛树脂的丙酸溶液，可以制得成膜质量好的稳定溶胶。（2）为探索采用MOD方法在LaAlO₃（001）单晶基片上制备性能良好的YBCO超导薄膜的最佳热处理条件，我们在分解热处理条件相同的情况下改变成相、渗氧热处理的温度，确定了薄膜制备的最佳热处理工艺。（3）XRD测试表明由溶胶制成的YBCO薄膜形成了比较完全的YBa₂Cu₃O_7-φ超导相，分析表明YBCO具有良好c轴取向，同时杂相较少。（4）SEM测试分析YBCO薄膜具有较好的表面形貌，但样品转变温度（Tc）较低。更多还原

【Abstract】 YBCO high temperature superconductor film holds great promise for applications in military affairs, iatrology, electronic and so on. Presently the main methods of preparing YBCO films have magnetron sputtering and laser deposition. In this paper the dense YBCO films with perovskite structure were expected to be prepared by metal organic deposition （MOD） process. The confecting methods of sot were discussed using inorganic salt as precursors, and the FT IR was adopted to analyse the chemical reaction and film forming mechanism of stable sol. The techniques of preparing film buffer layers on LaALO₃ were studied. The SEM, TEM and XRD were adopted to study the crystal structure of films. The influences of substrate and heat treatment condition on the crystal structure and performance of the YBCO films were discussed. The results are listed as follows:（1）The inorganic formate of Y, Ba and Cu was used as precursors, for example, Y₂O₃, BaCO₃ and CuO, and PVB of Propionate as complexed agents. The stable fluorine-free YBCO sol can be obtained.（2）In order to search after the best temperature in which YBCO superconductor film can be prepared on the single crystal of LaAlO₃ by MOD method. We change the high temperature of heat treatment in the condition of the same decomposed temperature.（3）The XRD testing show that the film of YBCO superconducting structure had been prepared. And it was indicated that YBCO is tropism of C axes. Few A axes tropism exist.（4） The SEM testing show that the film of YBCO surface is very good, but the Tc is low.更多还原