The fabrication and optimization of plasmonic nanostructures have many interesting and important applications including advancements in surface-enhanced Raman spectroscopy (SERS). One popular and cost-effective method to fabricate plasmonic nanopatterns is by a colloid template. By combining close-packed colloid monolayer and dynamic shadowing growth, we demonstrate that a variety of nanopatterns, such as nano-triangles, nano-cup triangles, hexagonal holes, and dual triangles, can be fabricated by varying vapor deposition angle, the substrate azimuthal rotation, as well as the evaporation configuration. Especially when a two-source evaporator is used, dual triangles with different shapes and compositions are simultaneously formed. The formation of these nanopatterns can be predicted by numerical and Monte Carlo simulations. In addition, the visible localized surface plasmon resonance (LSPR) of these patterns can be tuned systematically by changing the deposition conditions and the colloidal monolayer. Their plasmonic properties can be understood through finite-difference time-domain simulations. The tunability of LSPR can be used to design optimized substrate for SERS.
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