微/纳结构三维形貌高精度测试系统  

Measurement System for 3D Profile of Micro/Nano Structures with High Resolution

作　　者：谢勇君[1,2,3] 史铁林[2,3] 刘世元[2] 

机构地区：[1]暨南大学电气自动化研究所,广东珠海519070 [2]华中科技大学数字制造装备与技术国家重点实验室,武汉430074 [3]武汉光电国家实验室(筹)光电材料与微纳制造研究部,武汉430074

出　　处：《光电工程》2010年第1期19-24,共6页Opto-Electronic Engineering

基　　金：国家自然科学基金重点项目(50535030);国家自然科学基金(50775090);新世纪优秀人才支持计划(NCET-06-0639);国家博士后科学基金(20070410930);广东省自然科学基金博士研究启动项目(9451063201002281);广东高校优秀青年创新人才培育项目(LYM08019);广西制造系统与先进制造技术重点实验室开放课题基金;暨南大学青年基金项目(51208027)

摘　　要：为实现微/纳结构三维形貌的高精度测量,提出利用显微干涉技术和偏振技术相结合的方法来研制微/纳结构三维形貌亚纳米级精度测试系统。首先,利用五步相移干涉技术采集5幅带有π/2相移增量的干涉条纹图。然后,通过Hariharan五步相移算法得到包裹相位图。最后,利用分割线相位去包裹算法和相位高度关系转换得到微/纳结构三维形貌。在测试过程中通过偏振片产生强度可调的线偏振光,再由1/2波片改变偏振光在分光镜中的分光比,补偿参考镜与试件的反射性能差异,可得到亮度适中且对比度高的干涉条纹图,从而有利于实现微/纳结构三维形貌的高精度测量。系统的轮廓算术平均偏差Ra的重复测量精度可达0.06nm,最大示值误差不到±1%,示值变动性不到0.5%。通过对标准多刻线样板、硅微麦克风膜和硅微陀螺仪折叠梁的三维形貌测量验证了系统的有效性和实用性。In order to test 3D profile of micro/nano structures with high resolution,a measurement system was developed based on microscopic interferometry and polarization technique. First,five interferograms with π/2-phase increase were acquired by five-step phase-shift interferometry. Then wrapped phase maps were calculated with Hariharan five-step-phase-shift algorithm. Finally,3D profile of micro/nano structure could be gotten with branch-cut unwrapping algorithm and the phase-height formula. A polarizer provided a polarization beam and adjusted its illumination power. The polarized beam was parceled into two perpendicular directions by a polarization-beam splitter,and the intensities proportion of the two beams could be adjusted by rotating a 1/2-waveplate making it possible to compensate the differences of the reflectances between the sample and the reference mirror. This arrangement allowed that the interferograms had the advantages of high contrast and optimum intensity,and this was useful to increase system resolution. The system＇s main performance parameters include the Ra-repeatability-measurement resolution better than 0.06 nm,the error indication better than ±1%,and the variation of indication better than 0.5%. The experimental work conducted on several typical micro/nano structures such as standard multi-indents structures,Si-microphone membranes and Si-micro-gyroscope folded-beams confirms that such a measurement system is efficient to characterize 3D profile of micro/nano structures with high resolution.

关 键 词：微/纳结构 显微干涉 偏振技术 三维形貌 

分 类 号：TH741.8[机械工程—光学工程]