Abstract
The thick photoresist SU8, by virtue of its good mechanical durability, water impermeability and dielectric properties on polymerisation, is widely used as a resin for making high aspect ratio, functional MEMS device structures and packaging parts. However, the difficulty associated with removal, stripping or re-patterning of the polymerised SU8 remains a serious issue. This paper presents a novel process, based on O2/SF6 plasma etching, for patterning or removal of fully cross-linked SU8. The Taguchi methodology is used to optimise the O2/SF6 mix for a high etch rate and low under cut.
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This work was supported by the UK Engineering and Physical Science Research Council, under grant No. GR/N18895-“Microengineered Axial-Flow Pumps and Turbines”
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Hong, G., Holmes, A.S. & Heaton, M.E. SU8 resist plasma etching and its optimisation. Microsystem Technologies 10, 357–359 (2004). https://doi.org/10.1007/BF02637103
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DOI: https://doi.org/10.1007/BF02637103