title: Influence of master fabrication techniques on the characteristics of embossed microfluidic channels.
abstract: We describe protocols for the fabrication of microfluidic devices in plastics using a number of different embossing masters. Masters were fabricated by deep reactive ion etching (DRIE) of silicon (100), wet etching of silicon (100) and (110), and SU-8 processing. Structures embossed into a cyclo-olefin polymer were characterized in terms of the quality of pattern transfer as well as of the surface roughness. High quality pattern transfer was achieved with masters containing structures with angled sidewalls. Pattern distortions occurring during de-embossing were minimized by using masters consisting of SU-8 (which has a thermal expansion coefficient close to that of the substrates). Structures embossed with SU-8 masters also exhibited the lowest surface roughness. However, due to structural deformation, the reusability of the masters prepared for this study extended to only five embossing experiments. Masters fabricated on silicon, on the other hand, were more robust, but were subject to breakage during the de-embossing phase of the experiment. The results of this study will guide researchers in choosing master fabrication methods that will provide profile and surface characteristics of embossed microfluidic channels that are advantageous to their specific application.
authors.affiliation: Cornell Nanofabrication Facility, Cornell University, Knight Laboratory, Ithaca, NY 14853-5403, USA.
authors.forename: Mandy B
authors.initials: MB
authors.lastname: Esch
authors.forename: Sahil
authors.initials: S
authors.lastname: Kapur
authors.forename: Gizaida
authors.initials: G
authors.lastname: Irizarry
authors.forename: Vincent
authors.initials: V
authors.lastname: Genova
mesh_terms: D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D006358:Hot Temperature; D008422:Materials Testing; D044085:Microfluidics / Q000295:instrumentation*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D011312:Pressure; D017655:Silicon Compounds / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D020099:Coated Materials, Biocompatible; D017655:Silicon Compounds