基于电化学沉积的高深宽比无源MEMS惯性开关的研制

基于电化学沉积技术在金属基底上制作了一种新型的无源MEMS惯性开关。针对高深宽比、细线宽微电铸用光刻胶模具制作过程中,由于SU-8胶膜严重侧蚀导致的胶膜制作困难、质量低下的问题,进行了紫外光刻试验研究。试验研究了不同曝光剂量和后烘时间对SU-8胶光刻效果的影响,优化了光刻工艺参数。采用降低曝光剂量和延长后烘时间相结合的方法解决了高深宽比、细线宽SU-8胶膜制作困难的问题,制作出高质量的微电铸用光刻胶模具。最后,在上述试验结果基础上制作了一种高深宽比、无源MEMS惯性开关。其外形尺寸为3935μm×3935μm×234μm,其中最细线宽12μm,单层最大深宽比达10∶1,多层最大深宽比达20∶1。

Development of High-Aspect Ratio Passive MEMS Inertial Switch Based on Electrochemical Deposition Technique

Based on the electrochemical deposition technique,a new passive MEMS inertial switch was fabricated on a metal substrate.In view of the problems of poor quality caused by the serious lateral erosion of SU-8 in the process of making high-aspect ratio and fine-line micro electroforming molds,SU-8 UV lithography was studied.The effects of different exposure dose and PEB (post exposure bake) time on SU-8 UV lithography were studied experimentally,and the parameters of UV lithography were optimized.By using the method of reducing the exposure dose and prolonging the PEB time,the problem of poor quality of high-aspectratio and fine-line SU-8 electroforming mold was solved successfully.Finally,on the basis of the above experimental results,a passive MEMS inertial switch with high-aspect ratio was developed.The external dimensions are 3935μtm×3935μtm×234μtm,of which the smallest line width is 12am,the highest aspect ratio of the single layer is 10∶1,and the highest aspect ratio of the multi-layer is 20∶ 1.