高温超导Bi_2Sr_(1.6)La_(0.6)CuO_6外延薄膜生长模式的AFM研究  

AFM study of growth mode of high temperature superconducting Bi 2Sr 1.6 La 0.6 CuO 6 epitaxal thin films

作　　者：陶宏杰[1] 杨海涛[1] 张鹰子[1] 杨多贵 李林[1] 赵忠贤[1] 

机构地区：[1]中国科学院物理研究所及凝聚态物理中心,国家超导重点实验室

出　　处：《电子显微学报》1999年第1期76-79,共4页Journal of Chinese Electron Microscopy Society

摘　　要：利用ＡＦＭ对在（１００）和与（１００）有６°切偏角的ＳｒＴｉＯ３基片上用射频溅射方法制备的高温超导Ｂｉ２Ｓｒ１．６Ｌａ０．４ＣｕＯ６＋δ（Ｂｉ２２０１）薄膜的生长模式进行了系统地研究。对应以上两类不同切割的基片，实验观察到两种不同的薄膜生长模式。对切偏角小于０．４°的（１００）ＳｒＴｉＯ３基片，本征的生长模式是梯田岛模式（Ｖｏｌｍｅｒ－Ｗｅｂｅｒ模式），每层的厚度为ｃ／２（１．２５ｎｍ）；在切偏角为６°的衬底上沉积的Ｂｉ２２０１薄膜则以台阶流模式（Ｓｔｅｐ－ｆｌｏｗｍｏｄｅ）生长。Ｂｉ系高温超导体的本征的二维特性决定了薄膜的生长模式。C axis oriented Bi 2Sr 1.6 La 0.4 CuO 6 (Bi2201) thin films deposited on flat planes of (100) SrTiO 3 substrates and vicinal planes (off angle～6°) of SrTiO 3 substrates by RF magnetron sputtering were studied with AFM (atomic force microscope).The superconducting transition temperature T C of these thin films reached 29K.Two typical growth modes have been observed.AFM images of thin films on flat planes of substrates showed terraced island growth model.By contrast,the Bi 2201 thin films on vicinal planes of substrates showed a step flow growth mode.To both growth modes,the growth unit is halfunit cell in c axis.No single spiral growth was found in Bi2201 thin films,which was thought to be the typical structure of YBCO thin films.The strong two dimentional property of the Bi system high temperature superconductors governs the growth mode of the thin films.

关 键 词：原子力显微学 外延膜生长 超导体 BSLCO 高TC 

分 类 号：TM262.05[一般工业技术—材料科学与工程]