低温PECVD法形成纳米级介质膜微观结构研究

采用俄歇电子能谱 ( AES)和傅里叶红外光谱 ( FTIR)分析低温 PECVD法形成纳米级 Si Ox Ny 介质膜的微观组分结构及其与制膜工艺间关系 ,通过椭圆偏振技术测试该薄膜的物理光学性能。研究结果表明 :该介质膜中氮、氧等元素均匀分布 ,界面处元素含量变化激烈 ;高、低反应气压变化对膜内微观组分影响有异 ;该薄膜是既含有类似 Si3N4 、又含有类似 Si O2 的非晶状态 ,呈现无序网络结构 ;随着含氮量或含氧量的增多 ,该膜分别向Si3N4 或 Si O2 成分较多的结构转化 ;优化制膜工艺形成的富氮 Si Ox Ny 膜的性能与结构方面得到提高。

Study of Microscopical Structure for the Dielectric Film in Nanometre Range Formed by Low Temperature PECVD

The microscopical composition structure and its relationship to fabricated film process of SiO_xN_y dielectric film in nanometre range formed by low temperature PECVD were analysed with Anger electron spectrum (AES) and Fourier transform infrared spectroscopy (FTIR). The physical and optical properties of the thin film were measured by ellipsometer. The research results show that the distributions of nitrogen, oxygen etc. elements in the dielectric film present uniformaly, the contents of these elements at the interface change strongly. The effects of chamber pressure variations under high and low ranges on film microscopical composition actions are different. The thin film is non-crystal state containing both similar Si_3N_4 and similar SiO_2. and it presents a structure of structureless net. With the increase of nitrogen or oxygen contents, the thin film changes respectively into the film in structure of more Si_3N_4or SiO_2. The nitrogen-rich SiO_xN_y film fabricated by the optimized process condition is improved in property and structure.