Large-Area Nanowire Arrays Achieving Surface Lattice Resonance for Highly Sensitive SERS Applications

Achieving high sensitivity, signal uniformity, and cost-effective large-scale fabrication of large-area surface-enhanced Raman scattering (SERS) substrates continues to pose a significant challenge. In order to break through the limitations of conventional SERS substrates and to meet the demands of high-throughput production, a strategy integrating programmable cyclic deposition with high-precision nanoskiving techniques is presented for the fabrication of large-area periodic nanowire arrays with adjustable geometric parameters and versatile material compositions in this study. By precisely controlling the stacking sequence and nanoskiving parameters, the structural dimensions and material composition can be finely tuned, which significantly enhances the coupling efficiency between localized surface plasmon resonance and Rayleigh anomaly, thereby enabling the excitation of high-quality-factor surface lattice resonances. The resulting arrays exhibit excellent structural integrity, uniform electromagnetic field distribution, and good signal reproducibility (RSD = 1.9%) over ≈206 mm². Notably, Ag150-Gap20-Ag150-Gap115-Period435 periodic nanowire arrays as the substrate exhibit excellent sensitivity with a detection limit as low as 1 × 10^-12 M for the target. This strategy offers an efficient, scalable, and material-adaptive method for high-throughput fabrication of SERS substrates, thereby facilitating its application in environmental monitoring, food safety, and bioanalysis.