HfO_2薄膜的离子束刻蚀特性研究  

Ion beam etching of HfO_2 film

作　　者：王旭迪 徐向东[1] 刘颖[1] 洪义麟[1] 付绍军[1] 

机构地区：[1]中国科学技术大学国家同步辐射实验室

出　　处：《光学精密工程》2004年第5期454-458,共5页Optics and Precision Engineering

基　　金：国家863 804主题专项资助项目(No.863 804 9 2)

摘　　要：实验研究了HfO2薄膜特性以及掩模材料AZ1350以Ar为工作气体下的离子束的刻蚀特性。给出了离子能量、离子束流密度和离子束入射角等因素与刻蚀速率的关系曲线,用最小二乘法拟合了上述因素与刻蚀斜率的函数关系方程;分析了光刻胶和基片在刻蚀过程中随刻蚀深度的变化对图形转移精度的影响,用AFM的Tapping模式测量了刻蚀前后HfO2薄膜表面质量的变化。结果表明刻蚀速率与离子能量的平方根,及速流密度成正比,并随离子束入射角变化而变化;与刻蚀前相比,刻蚀工艺降低了因HfO2薄膜刻蚀深度的增加引起图形转移精度下降,因此提高刻蚀选择比是获得高分辨率图形的前提。研究结果已应用到了在HfO2/SiO2多层膜衍射光栅的制作中。The ion beam etching of HfO2 film and AZ1350 photoresisit mask were investigated in argon. The etch rate and mechanisms were measured and analyzed as a function of ion energy, ion beam density and ion incidence angle. The equations of etch rate versus such parameters were developed by the least-square-fit. The fidelity pattern transfer of mask and substrate were analyzed with the etching depth. The surface quality before and after etching were examined with AFM tapping mode. The details of etch rate have been interpreted in terms of mechanism of etching. The results show that etch rate has linear dependence on square root ion energy and ion density and varies versus incidence angle. Compared with the unetched substrate the etching process slightly lowers RMS roughness and the fidelity pattern transfer degrades with the etched depth on HfO2 film as a result of poor selectivity towards photoresisit. So it is necessary to improve the selectivity to achieve high fidelity pattern transfer. These results have been applied in the fabrication of HfO2/SiO2 multiplayer diffractive grating patterns.

关 键 词：HFO2薄膜 离子束刻蚀 刻蚀速率 图形转移 表面质量 

分 类 号：O463.2[机械工程—光学工程]