MOD方法制备Y0.5Yb0.5BCO薄膜及其性能研究

Growth and Property of Y_(0.5)Yb_(0.5)BCO Films Prepared by MOD Method

采用低氟金属有机物沉积工艺,通过将浓度相同的YBCO、YbBCO前驱溶液按1:1的体积比混合,使元素Yb部分取代Y,成功制备了Y0.5Yb0.5BCO薄膜.该薄膜成份单一,具有很好的双轴织构;薄膜表面平整致密,没有裂纹和孔洞,元素分布均匀.虽然Yb部分取代Y降低了薄膜的临界转变温度(Tc),但有效提高了薄膜在高场下的场性能,如在77K,3T磁场下,Y0.5Yb0.5BCO薄膜的Jc值提高了1.26倍.为了进一步改善薄膜在低场下的性能,通过在Y0.5Yb0.5BCO前驱溶液中再加入6 mol%的TaCl5,成功地制备了Ta5+掺杂的Y0.5Yb0.5BCO薄膜,提高了薄膜在整个磁场范围内的载流能力.

Y0.5Yb0.5BCO film was successfully fabricated by fluorine-reduced metalorganic deposition （MOD） method through mixing the same concentrated YBCO and YbBCO precursor solution with 1：1 volume ratio. The film has strong （00l） peaks and well biaxial texture. The surface of the film is dense without any cracks and pores. Besides, the elemental distribution is well-proportioned-. It is found that the Yb elemental substitution improves the in-field properties effectively, especially at high fields, although it decreases the critical transition temperature （To） of the Y0.5Yb0.5BCO film. For example, the Jc value of Y0.5Yb0.5BCO film is as higher as 1.26 times than that of the pure YBCO film at 77K and 3T applied field. In order to further improve the property at lower field, 6mo1% TaC15 is added to Y0.5Yb0.5BCO precursor solution to obtain the Ta5＋-doped Y0.5Yb0.5BCO film. The current carrying ability of the Ta5＋-doped Y0.5Yb0.5BCO film is enhanced within the measured fields.