MoCVD法生长的YBCO/SrTiO_3超导薄膜的显微结构和缺陷

Microstructure and Defects in YBa_2Cu_3O_(7-x)/SrTiO_3(100) Superconducting Films Grown by MOCVD

用 X 射线衍射和高分辨电镜研究了 MOCVD 法生长的 YBCO/SrTiO_3超导薄膜的显微结构和缺陷.发现在 T_c≈80K,J_c 近似10~4A/cm^2的 c 轴择优取向的薄膜中,存在着非晶型夹杂,杂相和其它取向的123相,它们可能是限制薄膜超导性能进一步提高和导至重复性差的主要原因.

The microstructure and defects of YBCO/SrTiO_3 superconducting films grown by MOCVDwere studied via XRD and HREM.In samples with T_c(?)80K,J_c(?)10~4A/cm^2,the preferentialorientation of c-axis perpendicular to interface was found together with 123 phase in differentorientations impurity phases and also some amorphous inclusions.They can limit the improve-ment of superconducting properties of MOCVD films and their reproducibility.