Methodology and fabrication of adherent and crack-free SU-8 photoresist-derived carbon MEMS on fused silica transparent substrates. (11th January 2019)

• Record Type: Journal Article
• Authors: Pilloni, Oscar; Madou, Marc; Mendoza, Doroteo; Muhl, Stephen; Oropeza-Ramos, Laura
• Is Part Of: Journal of micromechanics and microengineering. Volume 29:Number 2(2019:Feb.)
• Publication Date: 2019-01-11
• Subjects: MEMS -- microstructure -- pyrolysis -- carbon -- transparent substrate -- SU-8; Microelectromechanical systems -- Periodicals; Micromechanics -- Periodicals; 621.38105
• DOI: 10.1088/1361-6439/aaf70f
• Languages: English
• ISSNs: 0960-1317

Abstract

Abstract: Development of carbon based micro electromechanical systems (C-MEMS) has enabled the fabrication of durable, low cost and biocompatible micro devices for specific applications. Thermochemical decomposition of SU-8 (a common photoresist) is often used to fabricate C-MEMS. However, this technique has yielded unreliable results when fabrication on transparent substrates is required due to cracking and detachment of the produced carbon micro structures. We present a methodology for the fabrication of photopatterned carbon films based on SU-8 deposited on transparent fused silica substrates. Specifically, we developed and implemented this methodology for carbon microstructure fabrication derived from SU-8 2035 and SU-8 3035. It was found that SU-8 3035 derived carbon microstructures were crack free and adhered well to the substrate, while SU-8 2035 resulted in fractured and detached carbon microstructures. In addition, we characterized the produced SU-8 3035 derived carbon by measuring its electrical resistivity (1.412 ± 0.011 mΩ m), inter-structure electrical resistance, contact angle (35.7° ± 6.0°), Raman spectrum and adhesion strength to the substrate. In brief, even though SU-8 2035 and SU-8 3035 are useful materials for C-MEMS fabrication, we found that SU-8 3035 is more suitable for the fabrication of crack free and adherent carbon microstructures on transparent fused silica substrates.