Abstract
Current trends in miniaturized diagnostics indicate an increasing demand for large quantities of mobile devices for health monitoring and point-of-care diagnostics. This comes along with a need for rapid but preferably also green microfabrication. Dry film photoresists (DFPs) promise low-cost and greener microfabrication and can partly or fully replace conventional silicon-technologies being associated with high-energy demands and the intense use of toxic and climate-active chemicals. Due to their mechanical stability and superior film thickness homogeneity, DFPs outperform conventional spin-on photoresists, such as SU-8, especially when three-dimensional architectures are required for micro-analytical devices (e.g. microfluidics). In this study, we utilize the commercial epoxy-based DFP ADEX to demonstrate various application scenarios ranging from the direct modification of microcantilever beams via the assembly of microfluidic channels to lamination-free patterning of DFPs, which employs the DFP directly as a substrate material. Finally, kinked, bottom-up grown silicon nanowires were integrated in this manner as prospective ion-sensitive field-effect transistors in a bio-probe architecture directly on ADEX substrates. Hence, we have developed the required set of microfabrication protocols for such an assembly comprising metal thin film deposition, direct burn-in of lithography alignment markers, and polymer patterning on top of the DFP.
Highlights
Miniature analytical devices represent a crucial component in the preparation of future personalized medicine with emphasis to point-of-care microscale total analysis systems
We introduce a lamination-free implementation of Dry film photoresists (DFPs) as substrates themselves that allows patterning of DFP ADEX via direct laser lithography, which is beneficial for prospective polymeric lab-on-chip, microprobe, and mesh electronic devices
DFPs are laminated onto the substrate, locally exposed by UV light using a lithographic mask or laser lithography, and the DFP is developed
Summary
Miniature analytical devices represent a crucial component in the preparation of future personalized medicine with emphasis to point-of-care microscale total analysis systems (μTAS) Such devices enable, for instance, virus detection, personalized cancer diagnostics, disease biomarker registration as well as single cell and cell culture studies [1,2,3]. Microfluidic devices operate mainly with liquid samples and were discussed for the sorting, analysis and manipulation of single-cells by electric, mechanical, biochemical, and electrophoretic methods, by means of piezoactuators and optical and acoustic tweezers [4] They enabled even to study the role of mechanical properties and biochemical signals on the migration and invasion of metastasizing cancer cells [5]. High resolution detection of the transepithelial transport of K +-, Na+-, and C l−-ions in the thin lining fluid at the surface of pulmonary epithelial cells would elucidate
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
