MeV ion implantation induces the formation of a gold nanoparticle grating on SiO2 surfaces

Ion implantation is a versatile technique for synthesizing metallic plasmonic nanoparticles and generating surface ripples. While both are well-documented independent phenomena, their integration into a single self-organized system remains largely unexplored in the MeV regime. This work integrates both processes to design periodic metallic nanoparticle arrays. Ripple patterns were induced on amorphous SiO 2 surfaces by 1.8 MeV Au ion implantation at a 60° incidence angle. Their growth dynamics were studied based on classical pattern formation models and a proposed geometrical shadowing effect. Subsequently, samples were thermally annealed in air (700–1000 °C) to promote gold nanoparticle synthesis. Annealing caused no noticeable dimensional changes in the ripples, demonstrating high structural stability. At 900 and 1000 °C, gold nanoparticles (20–120 nm) formed along the ripple crests, creating a gold nanoparticle grating (AuNPG). Optical absorption spectra show a localized surface plasmon resonance (LSPR) at 520–540 nm, characteristic of gold nanoparticles. Furthermore, electrostatic force microscopy (EFM) revealed non-capacitive charge localization at the ripple crests, providing a physical basis for the system’s anisotropic local electrostatic properties. These results establish MeV ion implantation as a robust technique for single-step nanostructuring of SiO 2 surfaces, offering significant potential for nanophotonics and anisotropic electrostatics.