We provide plasmonic nanostructes chip fabricated by a negative-tone hydrogen silsesquioxane (HSQ) resist using electron-beam lithography (EBL). Our nanostructures are metallic nanostructures with very small gaps that can down to 20nm. Together with template stripping method, our nanostructures have ultra-smooth metal surfaces that will reduce plasmon scattering loss. This fabrication process of plasmonic nanostructure chip can be scaled up to reusable silicon wafer scale.
These plasmonic nanostructures chip can have various structural colours which is depend on the metallic materials used (gold, silver, aluminium are most common used), and gap size (< 100 nm). The unique structural colorization is resulted from plasmon resonant interactions between light and metallic nanostructures.
The fascination of our plasmonic nanostructures chip is it has strong light absorption although its structure is smaller than diffraction limit of light. This strong-light interaction occurs even in optically thin layers. By carefully tuning the nanostructures, we can make the plasmonic nanostructures chip that selectively interact with specific wavelength (colour). The nanogaps also have very strong optical field enhancement factor which is ideal for surface enhance Raman spectroscopy. The plasmonic nanostructures chip works seamlessly with our uRaman series for SERS study. Other applications include second-harmonic generation, photoluminescence enhancement and reflective tunable color surface.