YBa_2Cu_3O_(7-x)前驱液中铜含量对薄膜取向演变的影响

Effect of copper content in YBa_2Cu_3O_(7-x) precursor solution on orientation evolution of films

在化学溶液法制备YBa2Cu3O7-x(Y123)薄膜过程中,温度和氧分压是影响薄膜取向的重要因素。然而,当薄膜中金属离子比Y∶Ba∶Cu为1∶2∶3(即Y123成分)时,仅靠调控温度和氧分压两个参数很难获得a轴择优取向的Y123薄膜,主要原因在于忽视了薄膜成分对其取向的影响。研究了Y123前驱液中铜含量对Y123薄膜取向演变的影响。研究发现,前驱液中Cu含量对薄膜取向影响很大。在所得薄膜成分中,如果Cu含量过量,则有利于a轴取向;如果Cu含量不足,则有利于c轴取向。随着Y123前驱液中Cu含量的增加,a轴取向薄膜的生长窗口有增大趋势。当金属离子比Y∶Ba∶Cu为1∶2∶4时,薄膜的a轴取向度达到最大,最大值约为70%。

During preparing YBa2Cu3O7-x(Y123)films using chemical solution deposition,temperature and oxygen partial pressure are important factors affecting film orientation.However,the Y123 film with the a-axis preferred orientation is difficult to achieve by altering only the both parameters of temperature and oxygen partial pressure,when the metal ion ratio of Y∶Ba∶Cu in the film is 1∶2∶3.The main reason is that the influence of the film composition on its orientation is neglected.In this paper,the effect of copper content in Y123 precursor solution on the orientation evolution of Y123 film was investigated.The study found that the Cu content in the precursor solution has a great influence on the orientation of the film.In the obtained film component,if the Cu content is excessive,the a-axis orientation is favored;if the Cu content is insufficient,the c-axis orientation is favored.With the increase of Cu content in the Y123 precursor solution,the growth window of the a-axis oriented film has an increasing tendency.When the metal ion ratio Y∶Ba∶Cu is 1∶2∶4,the degree of a-axis orientation of the film reaches a maximum,and the maximum value is about 70%.