中文摘要：

采用三氟乙酸盐-金属有机沉积法（TFA-MOD）在铝酸镧单晶基体上制备了YBa2Cu3O7-x（YBCO）超导薄膜.通过改变前驱液的成分,研究了金属元素的不同化学计量比对YBCO薄膜的结构和性能的影响.结果表明,按照钇盐Y（CH3COO）3与钡盐Ba（CH3COO）2的比例为Y∶Ba=1∶1.5时所制备的YBCO薄膜的临界电流密度比严格按化学计量比Y/Ba=1/2制备的YBCO薄膜增大20%,达到5.0MA/cm2（77K,0T）.由X射线衍射分析得知,样品中所生成的杂质相Y2Cu2O5可能起到了磁通钉扎的作用从而提高了YBCO薄膜的临界电流密度.

英文摘要：

The YBCO films were prepared on LAO single crystal by TFA-MOD process.The structure and properties of YBCO films were investigated through changing the Y123 stoichiometry.It is found that higher JC values in self-filed of YBCO films are achieved by using the starting solution with the Ba∶ Y ratio of 1.5∶ 1.Xray diffraction analysis revealed that Y2Cu2O5 phases are formed in the final YBCO films,which may lead to very effective vortex pinning and then enhance the JC of YBCO films.