在金属基底上制作高深宽比金属微光栅的方法  

Fabrication of metal micro-grating with high aspect ratio on metal substrate

作　　者：杜立群[1,2] 鲍其雷 赵明[2] 王翱岸[2] 

机构地区：[1]大连理工大学精密与特种加工教育部重点实验室,辽宁大连116024 [2]大连理工大学辽宁省微纳米及系统重点实验室,辽宁大连116024

出　　处：《光学精密工程》2015年第3期700-707,共8页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.51375077;No.51075057)

摘　　要：根据光学领域对高深宽比金属微器件的需求,利用UV-LIGA工艺在金属基底上制作了具有高深宽比的金属微光栅。采用分层曝光、一次显影的方法制作了微电铸用SU-8胶厚胶胶模,解决了高深宽比厚胶胶模制作困难的问题。由于电铸时间长易导致铸层缺陷,故采取分次电铸等措施得到了电铸光栅结构;同时通过线宽补偿的方法解决了溶胀引起的线宽变小问题。在去胶工序中,采用"超声-浸泡-超声"循环往复的方法。最终,制作了周期为130μm、凸台长宽高为900μm×65μm×243μm的金属微光栅,其深宽比达到5,尺寸相对误差小于1%,表面粗糙度小于6.17nm。本文提出的工艺方法克服了现有方法制作金属微光栅时高度有限、基底易碎等局限性,为在金属基底上制作高深宽比金属微光栅提供了一种可行的工艺参考方案。According to the requirements of optical fields for metal micro devices with higher aspect ratios,a metal micro-grating with the high aspect ratio was fabricated on a metal substrate by using the UV-LIGA technology.The ＂exposure step by step＂and ＂development once＂were used to fabricate a SU-8thick photoresist mold with high aspect ratio to overcome the technologic difficulty in fabrication processing.For the defects of electroforming layer caused by long operation time,the fractional electroforming and other methods were adopted to obtain the electroforming grating structure..At the same time,the line width compensation method was taken to solve the problem that line width of SU-8 photoresist mold was reduced by swelling.In the process of stripping photoresist after electroforming,the ultrasonic method and soaked method were alternately used.Finally,the metal micro-grating with a period of 130μm,and a size of 900μm×65μm×243μm was fabricated.The high aspect ratio of the metal micro-grating reaches 5,and its relative error on overall dimensions is lower than 1%.Moreover,the surface roughness of metal micro-grating is lower than6.17 nm.This research breaks the height limitation and substrate fragile of the exciting fabrication methods for metal micro-gratings with high aspect ratios.

关 键 词：金属微光栅 高深宽比 UV-LIGA工艺 SU-8厚胶 微电铸 

分 类 号：O436.1[机械工程—光学工程] TH741.6[理学—光学]