BST薄膜的反应离子刻蚀研究

钙钛矿结构的钛酸锶钡(BST)薄膜作为优良的介电、铁电材料在新一代的微机械系统(MEMS)、动态存储器(DRAM)及其他器件上的广泛应用,使得BST薄膜的刻蚀特性越来越重要。该文利用反应离子刻蚀装置,研究了溶胶-凝胶工艺制备的钛酸锶钡薄膜在CHF3/Ar等离子气体中的刻蚀情况。通过分析刻蚀速率及薄膜刻蚀前后表面形貌的变化,结果表明,刻蚀过程是离子轰击、离子辅助化学反应和化学反应刻蚀共同作用的结果。刻蚀速率为5.1 nm/min。Sr元素较难去除,成为阻碍刻蚀的重要因素。

Characteristics of Reactive Ion Etching of BST Thin Film

Perovskite(Ba,Sr)TiO_3(BST) thin film is prepared via Sol-Gel methods.The etching characteristics of Sol-Gel-derived BST films were investigated in a reactive ion etching(RIE) setup using CHF_3/Ar plasma.The morphology and etching rate were measured by X-ray diffraction(XRD) and atomic force microscopy(AFM).The properties of the micropattern after etching were measured by SEM and EDS system.The etching mechanism of BST thin film in RIE was the cooperation of ion bombardment,ions assist chemical reaction and reaction etching effects.The Sr atoms were hard to remove off than any other atoms.The higher etching rate can be up to 5.1 nm/min.