极紫外光刻照明系统宽带Mo/Si多层膜设计与制备  

Design and Fabrication of Broadband Mo/Si Multilayer Films for Extreme Ultra Violet Lithography Illumination System

作　　者：喻波[1,2] 李春[1] 金春水[1] 王春忠[3] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室,吉林长春130033 [2]中国科学院大学,北京100049 [3]吉林大学物理学院,吉林长春130012

出　　处：《中国激光》2016年第4期154-160,共7页Chinese Journal of Lasers

基　　金：国家科技重大专项(2008ZX02501-004)

摘　　要：针对极紫外光刻照明系统中一块小尺寸反射镜大入射角带宽的需求,采用Si层有效厚度与公转速度关系式和多层膜周期厚度与公转速度关系式,完成了宽带Mo/Si多层膜设计膜系的制备工作。在磁控溅射镀膜机上制备了一系列不同周期厚度和G值（Mo层厚度与多层膜周期厚度的比值）的Mo/Si多层膜规整膜系,并利用掠入射X射线反射谱表征,分别得到多层膜周期厚度、Mo层有效厚度和Si层有效厚度与公转速度的关系式以及多层膜界面粗糙度。采用Levenberg-Marquardt算法完成了宽带膜系设计,设计结果为在16.8°~24.8°范围内R=42%±1%。根据Mo/Si多层膜周期厚度和Si层有效厚度与公转速度的对应关系制备所设计的膜系,并对其极紫外波段反射率进行测量,实验结果为在16.8°~24.8°范围内R=41.2%~43.0%,实验结果与设计结果吻合得很好,进一步的制备误差反演分析表明实验结果与设计结果之间的细微偏差主要来自Mo/Si多层膜G值及界面粗糙度标定过程中的系统误差。To meet the wide angular bandpass requirement of a small-size mirror in extreme ultra violet（EUV）lithography illumination system, the designed broadband molybdenum（Mo） /silicon（Si） multilayer stack is deposited by using the relationship between effective thickness of Si layers and velocity and the relationship between periodic thickness of multilayers and velocity. Mo/Si periodic multilayers with different periodic thicknesses and G（ratio of Mo layer thickness and periodic thickness of multilayer films） are deposited by magnetron sputtering and characterized by small-angle X-ray reflectometry. The relationship between periodic thickness of multilayers and velocity, the relationship between effective thickness of Mo and Si layers and velocity, and the interface roughness of multilayers are provided by characterization of X-ray reflection spectrum. The broadband multilayer stack is designed by utilizing the Levenberg-Marquardt algorithm, and the designed EUV reflectance is R=42%±1% at the range of 16.8°~24.8°. The designed stack is deposited according to the relationship between effective thickness of Si layers and velocity and the relationship between periodic thickness of multilayers and velocity. The measured EUV reflectance of the broadband Mo/Si multilayer stack is 41.2%~43.0% at the range of 16.8°~24.8°, which is very close to the designed value. Further fabrication error reversion indicates that the small difference between the experimental and designed results is mainly caused by the systematic error in the calibration of G value and interface roughness of Mo/Si multilayers.

关 键 词：薄膜 极紫外光刻 宽带多层膜 MO/SI多层膜 

分 类 号：O484.5[理学—固体物理] O434.19[理学—物理]