介绍了一种基于玻璃湿法刻蚀低成本的MEMS压印模版制作工艺,工艺中以单层光刻胶作为刻蚀掩模,重点研究了改善刻蚀图形几何轮廓和提高表面质量的方法.在对钻蚀形成机理进行分析的基础上,通过对比偶联剂不同涂敷方式及不同蒸镀时间对刻蚀结果的影响,优化了硅烷偶联剂的涂敷工艺,使钻蚀率降低到0.6,图形几何形状得到改善.分析了刻蚀生成物的溶解度,采用HCl作为刻蚀液添加剂对刻蚀产生的难溶物进行分解,提高了表面质量.对刻蚀表面缺陷的形成原因进行了分析,采用厚胶层工艺消除了表面缺陷.利用该工艺制作了图形特征尺寸为100 μm的MEMS压印模版,并进行了初步压印实验,得到了很高的复型精度.
A fast and low-cost imprint template fabrication process is presented, which is based on glass wet etching using a soft etching mask. The emphasis is focused on the improvement of the pattern geometry profile and the surface quality. After analyzing the undercut formation mechanism, silane coupler coating process is optimized by investigating the effects of various coating methods, evaporation time and temperature of silane coupler on the etched results, which reduces the undercut ratio to 0.6 and improves the pattern profile. The main contributors to the surface roughness are identified by comparing the solubility product constant of various insolubles produced during etching, and good surface quality is obtained by using hydrochloric acid as etching additive. Main factors causing surface defects are analyzed and thick soft etching mask is adopted to eliminate the surface defects. The imprint template with pattern feature size of 100 μm is fabricated using the developed process. The preliminary imprint experiments are performed and high fidelity replicas of the pattern on template are obtained.