分别以CF4/Ar和CF4/Ar/O2作为刻蚀气体,采用磁增强反应离子刻蚀(MERIE)技术对sol-gel法制备的BST薄膜进行刺蚀.结果表明,刺蚀速率与刻蚀气体的混合比率呈现非单调特性.当CF4/Ar的气体流量比R(CF4:Ar)为10:40时,刻蚀速率达到极大值.当CF4/Ar/O2的气体流量比R(CF4:Ar:O2)为9:36:5时,刻蚀速率达到最大值,最大刻蚀速率为8.47nm/min.原子力显微镜(AFM)分析表明,刻蚀后的薄膜表面粗糙度变大。对刻蚀后的薄膜再进行适当的热处理,可以去除部分残留物。
BST thin films prepared by sol-gel method were etched in CF4/Ar and CF4/Ar/O2 plasmas using magnetically enhanced reactive ion etching (MERLE) technology. Results indicate that etching rates of BST thin films present non-monotonic dependence on mixing ratio of etching gases. Etching rate reaches a maximin value at the gas flow ratio of CF4/Ar is 10 : 40. The maximum etching rate is 8.47 nm/min when R (CF4: Ar: 02) is equal to 9 : 36 : 5. The images of atomic force microscopy (AFM) show that the roughness of etched surface gets rugged in comparison with the unetched surface. Furthermore, the residues on the etched surface could be removed partly by postannealing properly.