Process optimization and characterization of silicon microneedles fabricated by wet etch technology

In this research, we have optimized a fabrication technique for manufacturing microneedle arrays in standard silicon wafer ((100) orientation) using potassium hydroxide (KOH) wet etching. The etch behaviour of silicon was simulated for different mask shapes and sizes using SIMODE software. In the context of the fabrication process, we demonstrate the influence of the mask design and the processing environment such as etching parameters and etch bath conditions on the formation of silicon microneedle structures (needle height up to 300 μm) and its reproducibility. Single needle shear tests have been carried out to characterize the mechanical stiffness of fabricated microneedles.

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