双频干涉共焦台阶高度测量系统  

System to Measure Step Hight by Combining Dual-frequency Interferometry and Confocal Microscopy

作　　者：林德教[1] 柳忠尧[1] 张蕊[1] 殷纯永[1] 徐毅[2] 

机构地区：[1]清华大学精密仪器与机械学系精密测量技术与仪器国家重点实验室,北京100084 [2]中国计量科学研究院,北京100013

出　　处：《中国激光》2003年第11期1015-1018,共4页Chinese Journal of Lasers

基　　金：国家自然科学专项基金 (No .5 0 0 2 70 0 2 );清华大学博士生创新基金联合资助项目

摘　　要：提出了一种以低频差横向塞曼双频激光器作光源的外差干涉共焦显微测量系统 ,该系统通过共焦显微的光强测量进行粗定位 ,其轴向台阶高度测量范围在 5 μm以上。同时采用相位测量技术 ,实现了对半波长的 36 0 0细分 ,从而使测量分辨率达到 0 1nm。由此同时满足了高测量精度和较大测量范围的要求。实验结果表明系统在没有恒温的普通实验室条件下 1h内的漂移不超过 15nm ,与差动纳米双频干涉仪的比对结果线性系数在 0 9999以上 ,非线性误差约 10nm。A novel measuring system is proposed in this paper, which is based on transverse Zeeman laser with low beat frequency and combined heterodyne interferometry and confocal microscopy. The range of height measurement reaches over 5 μm in term of intensity derived from the confocal system. Meanwhile the phase measurement technology is adopted to divide half wavelength by a factor of 3600, hence a resolution of 0.1nm can be attained. Accordingly the requirements of both high measurement resolution and relatively large measurement range are met simultaneously. The experimental results show that in ordinary laboratory condition, without constant temperature, the shift of phase measurement is about 15 nm. Calibration with differential dual-frequency interferometer gives the linealy correlation coefficient of 0.9999 and nonlinearity of about 10 nm.

关 键 词：测绘仪器 相位测量 外差干涉 共焦显微术 

分 类 号：TH744.3[机械工程—光学工程]