基于X射线吸收光谱全能谱拟合的金属薄膜面密度测量方法  

Approach for Measuring Surface Density of Metal Thin Films Based on Full Range Fitting of X-Ray Absorption Spectra

作　　者：王硕然 鄢志鸿 孙亦宸 王琦[2] 罗守华[1] Wang Shuoran;Yan Zhihong;Sun Yichen;Wang Qi;Luo Shouhua(School of Bioscience and Medical Engineering,Southeast University,Nanjing 210096,Jiangsu,China;Research Center of Laser Fusion,China Academy of Engineering Physics,Mianyang 621900,Sichuan,China)

机构地区：[1]东南大学生物科学与医学工程学院,江苏南京210096 [2]中国工程物理研究院激光聚变研究中心,四川绵阳621900

出　　处：《激光与光电子学进展》2024年第5期238-244,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(61871126);江苏省重点研发计划(BE2022828);江苏省前沿引领技术基础研究专项(BK20222002)。

摘　　要：提出一种基于X射线吸收光谱(XAS)的全能谱拟合方法,先通过样品元素的衰减系数曲线和射线源的本底能谱曲线获得样品的理论吸收能谱,再将理论吸收能谱与实际穿过样品的吸收能谱进行拟合,由退火算法计算得到薄膜样品的元素面密度值。该方案有效降低了噪声与探测器响应函数引入的误差。实验结果表明,系统在单元素下的测量结果重复测量标准偏差较小,测量不确定度在10-4g/cm^(2)量级,且能进行多元素薄膜面密度的测量,满足惯性约束聚变实验中对金属薄膜无损与高稳定的测量需求。We propose a method based on X-ray absorption spectra(XAS),which allows the calculation of each channel in the energy spectrum.The theoretical absorption energy spectrum of the sample is obtained using the attenuation coefficient curve of the sample elements and the background energy spectrum of the radiation source,and compares with the actual absorption energy spectrum of the sample.The energy spectrum is fitted and the element surface density is calculated with the annealing algorithm.The results show that the standard deviation of repeated experiments when measuring a single element is low and the measurement uncertainty is in the order of 10-4 g/cm^(2).This system can also be used for the measurement of the areal density of multi-element thin films,meeting the requirements of non-destructive and highly stable measurements of metal thin films in inertial confinement fusion experiments.

关 键 词：X射线吸收光谱 金属薄膜 面密度 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]