While wet pattern transferring of polymers is faster than dry processing, it can lead to excessive undercut that will erode and distort features in patterned sacrificial regions during micro electro mechanical systems (MEMSs) fabrication. Dry etching processes based on O₂, CF₄ and N₂ chemistry reduce undercutting of features to around 2 m, but the resulting sidewall profiles of the patterned polymer islands are generally unsuitable for subsequent conformal deposition of thin films for surface micromachined MEMS fabrication. This paper presents a dry etching process for Prolift-100-16 polymer sacrificial layers, that employs a combination of a hard mask and a subsidiary sacrificial layer, that overcomes the limitations of undercut control and conformal deposition of physical vapour deposition techniques. The dry etching process is optimized to reduce the feature undercut to as low as 1 m, while also producing sidewall profiles suitable for subsequent conformal deposition of thin films.

虽然聚合物的湿式图案转移比干式加工更快，但它会导致过度的底切，这会在微机电系统 (MEMS) 制造过程中侵蚀和扭曲图案化牺牲区域中的特征。基于 O ₂、CF ₄和 N ₂化学物质的干蚀刻工艺将特征的底切减少到大约 2m，但由此产生的图案化聚合物岛的侧壁轮廓通常不适合用于表面微加工 MEMS 制造的薄膜的后续保形沉积。本文介绍了 Prolift-100-16 聚合物牺牲层的干法蚀刻工艺，该工艺采用硬掩模和辅助牺牲层的组合，克服了物理气相沉积技术的底切控制和保形沉积的局限性。干法蚀刻工艺经过优化，可将特征底切降低至低至 1m，同时还产生适用于后续薄膜共形沉积的侧壁轮廓。