摘要
用小波变换的方法分析了纳米多层膜的X射线掠入射反射率测试曲线.从小波变换的自相关函数峰位和峰强度信息中得到了常规曲线拟合方法难以表征的含有氧化层、界面层或厚度漂移的多层膜结构,利用其作为多层膜的初始结构再进行常规的曲线拟合,可实现多层膜结构精确表征的目的.研究成功地鉴别出钒单层膜的表面存在约3 nm厚的氧化层,分析得到Mo/Si多层膜的界面纯粗糙度约0.42 nm,表明在Ni/C多层膜中接近表面和基底的膜层存在大于5%的厚度漂移.
Wavelet transform is used to analyze the grazing incidence X-ray reflectivity curve of nanometer multilayer structures. For the structures including oxide layers,interlayers or thickness fluctuations,which are difficult to determine, wavelet transform can be used to get structure parameters from the peak positions and peak intensities of auto-correlation functions. Using these results as initial model of further curve fitting, the multilayer structures can be characterized accurately. The oxide layer of vanadium monolayer is determined to be about 3nm,the interfacial roughness of Mo/Si multilayer structures is about 0.42nm,and the results show that the thickness fluctuations of layers close to surface and substrate are over 5 %.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2009年第9期2288-2293,共6页
Acta Photonica Sinica
基金
国家自然科学基金(10435050
10675091
10675092)
国家高技术研究发展计划(2006AA12Z139)
上海市科学技术委员会(07DZ22302)资助
关键词
薄膜光学
纳米多层膜
小波变换
自相关函数
氧化层
界面粗糙度
厚度漂移
Thin film optics
Nanometer multilayer
Wavelet transform
Auto-correlation function
Oxide layer
Interracial roughness
Thickness fluctuation