Robust parylene-to-silicon mechanical anchoring

This paper describes a new technique for strongly anchoring parylene (poly-para-xylylene) layers on a silicon substrate. Parylene has gained interest for MEMS applications due to its excellent properties. More specifically, because of its flexibility (Young´s modulus of 4 GPa), its chemical barrier properties, its conformal deposition and its biocompatibility, parylene is of great interest for microfluidics and BioMEMS. One of the issues with parylene processing is adhesion and delamination problems, occurring during fabrication or during device operation. Here, we report a new technique for anchoring parylene films on silicon using DRIE-etched trenches and anchors. We demonstrate a new way to completely protect the adhesion of parylene even when exposed to aggressive chemicals.