溶胶-凝胶方法制备BiFeO3薄膜的微结构和晶粒尺寸效应
The microstructure and grain size effect of BFO thin films prepared by sol-gel method
-
摘要: 使用溶胶凝胶法在Pt/Ti/SiO2/Si衬底上生长不同厚度与不同稀土掺杂（Nd,Ce,La）的BiFeO3（BFO）薄膜,高分辨X射线衍射实验结果表明薄膜是由无择优取向的多晶成份组成,不同厚度和掺杂的薄膜都呈现三方相。对比不同厚度BFO薄膜的结构发现,随着薄膜厚度的增加,薄膜的晶粒尺寸呈现增大的趋势,同时晶格常数也随之增大;比较不同掺杂的薄膜,发现随掺杂原子的离子半径增大（Nd,Ce,La）,薄膜的晶粒尺寸随之减小,同时薄膜的晶格参数变小。这些结果表明在BFO薄膜中存在晶粒尺寸效应,BFO的晶格随着晶粒尺寸的增大而增大。Abstract: BiFeO3（BFO） thin films with different thickness/dopants（Nd,Ce,La） were fabricated on Pt/Ti/SiO2/Si substrate by sol-gel method.High-resolution XRD result indicates all the thin films are composed by polycrystalline BFO with no preferred orientations,and present the phase of rhombohedral. With the thickness increasing,the films exhibit larger grain size and lattice constants.With the ionic radius of doped element ions increasing（Nd,Ce,La）,the grain size and lattice constants of thin films are decreasing.These results indicate that grain size effect exists in BFO films.
下载: