Infrared micro-embossing of thermoplastics

This paper reviews experimental work on through-transmission infrared micro-embossing of thermoplastics for replication of micro-fluidic devices. Two separate modes were evaluated. In one mode, a transparent mold/die was used in where IR radiation was passed through a die and directed onto an opaque thermoplastic substrate. The substrate would heat and soften and then the die was pressed against the substrate, allowing the features of the mold/die to be transferred to the substrate. In contrast, the other mode that was evaluated involved passing IR radiation through a transparent substrate onto an absorbing die that would heat as it was pressed against the substrate. The parameters that were evaluated included: power density, heating time, preheating, holding time, and pressure. Optical microscopy evaluation of the samples allowed correlation of these parameters to image transfer quality, including depth of features (Over 100 μm) and sharpness.