硅基非球面柱面微透镜阵列制备方法  

Preparation method of silicon-based aspheric cylindrical microlens array

作　　者：张畅达 高明友[1] 周岩 邓晓洲 熊欣[1] 刘风雷[1] 张为国[1] Zhang Changda;Gao Mingyou;Zhou Yan;Deng Xiaozhou;Xiong Xin;Liu Fenglei;Zhang Weiguo(Research Center for Micro-Nano Manufacturing and System Integration,Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,Chongqing 400714,China;School of Information Science and Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Tianjin Jinhang Institute of Technical Physics,Tianjin 300308,China)

机构地区：[1]中国科学院重庆绿色智能技术研究院微纳制造与系统集成研究中心,重庆400714 [2]重庆交通大学信息科学与工程学院,重庆400074 [3]天津津航技术物理研究所,天津300308

出　　处：《红外与激光工程》2022年第7期377-385,共9页Infrared and Laser Engineering

基　　金：国家自然科学基金(61775213)。

摘　　要：非球面柱面微透镜是一种重要的微光学元件,具有激光准直、聚焦、匀化等功能,在激光通信、光纤传感、激光雷达测距、激光泵浦等系统中具有广泛的应用。为了减小光电系统的体积、提升光纤性能,增大透镜数值孔径是一种常用的解决方案。提出采用折射率更大的硅作为低折射率石英基底的替代材料,使得微透镜在相同体积下数值孔径大幅提升,同时可以降低加工量从而提升制备效率。针对传统石英微透镜的制备方法不再适用硅基微透镜的问题,提出基于掩模移动曝光方法制备光刻胶非球面图案,使用多次涂胶和循环曝光方法,分别解决厚胶涂覆均匀性差及曝光掩模痕迹明显等问题,最终利用等离子体刻蚀技术进行图案转移传递,从而实现微透镜的制备。以数值孔径2.9的硅基非球面柱面透镜阵列为例开展实际制备工艺实验,所制备的微透镜列阵面型精度PV为0.766μm,表面粗糙度Ra为3.4 nm,表面光洁与设计值符合较好,验证了制备方法的可行性。该方法有望促进非球面柱面微透镜列阵在紧凑化红外光电系统中的大规模应用。An spherical cylindrical lens is an important micro-optical element that has the functions of laser collimation,focusing,homogenization,etc.,and has a wide range of applications in laser communication,optical fibre sensing,lidar ranging,laser pumping and other systems.To reduce the volume of the optoelectronic system and improve the performance of the optical fiber,increasing the numerical aperture of the lens is a common solution.Proposes the use of silicon with a higher refractive index as an alternative material for the low refractive index quartz substrate,which greatly increases the numerical aperture of the lens under the same volume and at the same time reduces the amount of processing and improves the manufacturing efficiency.Aiming at the problem that traditional quartz microlens preparation methods are no longer suitable for silicon-based lenses,a mask-based moving exposure method is proposed to prepare photoresist aspheric patterns using multiple spin coating and cycle exposure methods to solve problems such as poor thick photoresist surface uniformity and obvious traces of the exposure mask.Plasma etching technology is finally used to transfer the pattern to realize the preparation of the microlens.Taking a silicon-based aspherical cylindrical microlens array with a numerical aperture of 2.9 as an example,the actual preparation process experiment was carried out.The surface precision PV of the prepare microlens array is 0.766 μm,the surface roughness Ra is 3.4 nm,and the surface finish was in line with the design value.The feasibility of the preparation method was verified.This method is expected to promote the large-scale application of aspheric cylindrical microlens array in compact infrared optoelectronic systems.

关 键 词：光学工程 非球面柱面微透镜阵列 移动掩模 硅基 大数值孔径 等离子体刻蚀 

分 类 号：O439[机械工程—光学工程]