Experimental investigation of microfluidic feature manufacturing by Digital Light Processing stereolithography

Lab on Chips (LOCs) are devices, mostly based on microfluidics, that allow to perform one or several chemical, biochemical or biological analysis in a miniaturized format on a single chip. The Additive Manufacturing processes, and in particular the Digital Light Processing stereolithography (DLP-SLA), could quickly produce a complete LOC with high resolution 3D features in a single step, i.e. without the need for assembly processes, and using low cost and user-friendly desktop machines. However, the potential of DLP-SLA to produce non-planar channels or channels with complex sections has not been fully investigated yet. This study proposes a benchmark artifact (including also some channels with their axis lying in a plane parallel to the machine building platform) aiming at assessing the capability and performance of DLP-SLA for manufacturing microfeatures for microfluidic devices. A proper experimental campaign was performed to evaluate the effect of the main process parameters (namely, layer thickness and exposure time) on the process performance. The results pointed out that both the process parameters influence the quality and dimensional accuracy of the analyzed features.