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YBa_2Cu_3O_(7-δ)(YBCO)超导薄膜的表面形貌对于自身的超导性能起着至关重要的作用.低温热处理过程对于最终的YBCO超导薄膜的表面形貌有非常大的影响.我们研究了升温速率和气体流量对表面形貌的共同作用,发现以下规律:在高气体流量的作用下,当升温速率较低时,薄膜出现裂纹,提高升温速率,可得到光滑薄膜,进一步提高升温速率产生褶皱,直至出现裂纹与褶皱的共存态;在低气体流量下,升温速率较低时也能获得光滑的薄膜,而高升温速率则会导致薄膜褶皱.因此获得表面平整的薄膜,升温速率和气体流量必须匹配.结合在线实时观测的方式,观察了缺陷表面的形成温度及演化过程,给出了薄膜表面形貌与热处理条件关系的解释.原子力显微镜(AFM)粗糙度的测试结果与我们的解释吻合.
The surface morphology of YBa_2Cu_3O_ (7-δ) (YBCO) superconducting thin films plays a crucial role in the superconductivity of YBCO superconducting films, and the low temperature heat treatment has a great influence on the surface morphology of the final YBCO superconducting films. We investigated the synergistic effect of heating rate and gas flow on the surface topography and found the following rule: under the action of high gas flux, when the heating rate is low, the film cracks and the heating rate is increased, and a smooth film can be obtained, further improving Folds occur at a heating rate until the coexistence of cracks and folds occurs. Smooth films are also obtained at lower rates of heating at low gas flows, whereas films of high film thickness are obtained at high rates of temperature rise. The velocity and gas flow rate must be matched.The formation temperature and evolution of the defect surface are observed by means of online real-time observation, and the relationship between the film surface morphology and the heat treatment condition is explained.Finally, the results of atomic force microscopy (AFM) Our explanation is consistent.