Large-scale diamond silver nanoparticle arrays as uniform and sensitive SERS substrates fabricated by surface plasmon lithography technology

Abstract

Surface-enhanced Raman scattering (SERS) is still treated as an ultrasensitive analytical tool in various applications. However, it remains to be a challenge in manufacturing large-scale and uniform substrates. Here, a novel fabrication method, surface plasmon lithography (SPL) technology, is developed to fabricate large-scale and uniform diamond silver nanoparticle (DSN) arrays with inter-nanoparticle gap of 30 nm. Experimentally, the fabricated SERS substrates are uniform within a large scale of 10 mm2. Besides, the enhancement factor (EF) larger than 107 is obtained via detecting Rhodamine 6G molecules, deriving from the enhanced electromagnetic (EM) field in the form of catenary optical fields between neighboring DSNs. Our work demonstrates that SPL technology is a straightforward approach for easily fabricating gap-controllable SERS substrates with large area, high uniformity and high sensitivity.