3D thermoshrink micropillar array metasurface biochemical sensor at the terahertz frequency

This study presents what we believe to be a novel method using a laser-induced heat-shrinkable polymer to leverage the rapid processing capabilities of femtosecond-laser-prepared microstructures and accelerate the fabrication of three-dimensional optical metasurface biochemical sensors. Arrays of micropillar unit structures, each 220 µm in height, were successfully fabricated by modulating laser-induced contraction. These arrays exhibited exceptional performance in fingerprint spectral coupling and biochemical sensing, achieving detection limits of 6 nM for lactose and 8 pg/mL for the SARS-CoV-2 S protein. The metasurface sensors demonstrated high sensitivities and low detection limits, while the simplified manufacturing process further enhanced device performance, highlighting the method’s potential for advanced biochemical sensing applications.