A rapid method for fabricating an injection molding tool using current MEMS processing is presented. The process was used to fabricate micro fluidic channels in a plastic substrate with depths of 27μ m. The tool was made using a photosensitive SU-8 epoxy on silicon. Two polymers were successfully used for injection molding the channels, clear rigid polycarbonate and opaque flexible polypropylene. Tool fabrication time was approximately 30 minutes and survived, 22 shots for polypropylene and 8 shots for polycarbonate. Deformities of the channels were observed in both plastics. Channel height was increased by 2-3μm due to a ridge that was formed from shear forces generated between the walls. The channel width shrunk approximately 7.9% maximum for polypropylene.
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