Patterning of Silicone Rubber for Micro-Electrode Array Fabrication

Abstract

Five methods of micro-patterning silicone rubber, (polydimethylsiloxane, PDMS) are reviewed. Three of the methods are experimentally evaluated in order to find the most suitable process parameters to expose electrode sites and contact pads of PDMS-embedded platinum structures for fabricating micro-electrode arrays. Rated by applicability, type of PDMS involved (implantable-grade required), achievable aspect ratio (AR) and minimum feature size (FS), the feasibility of two methods was demonstrated: laser-ablation, using a Nd:YAG laser (AR = 5.3, FS > 100 mum) and dry etching using a reactive ion etcher (AR = 10, FS > 10 mum).