Characterisation of PMMA microfluidic channels and devices fabricated by hot embossing and sealed by direct bonding

In this study we fabricated a silicon-based stamp with various microchannel arrays, and demonstrated successful replication of the stamp microstructure on poly methyl methacrylate (PMMA) substrates. We used maskless UV lithography for the production of the micro-structured stamp. Thermal imprint lithography was used to fabricate microfeatured fluidic platforms on PMMA substrates, as well as to bond PMMA lids on the fluidic platforms. The microfeature in the silicon-based (silicon wafer coated with SU-8) stamp includes microchannel arrays of approximately 30 mu m in depth and 5 mm in width. We produced various channels without pillars, as well as with SU-8 pillars in the range of 50-100 mu m wide and 6 pm in height. PMMA discs of 1 mm thickness were utilized as the molding substrate. We found 10 kN applied force and 100 degrees C embossing temperature were optimum for transferring the microstructure to the PMMA substrate. (C) 2009 Elsevier B.V. All rights reserved.