Copolymer template control of gold nanoparticle synthesis via thermal annealing

Here we present an original process combining top-down and bottom-up approaches by annealing a thin gold film evaporated onto a hole template made by etching a PS–PMMA copolymer film. Such process allows a better control of the gold nanoparticle size distribution which provides a sharper localized surface plasmon resonance. This makes such route appealing for sensing applications since the figure of merit of the Au nanoparticles obtained after thermal evaporation is more than doubled. Such process could besides allow tuning the localized surface plasmon resonance by using copolymers with various molecular weights and thus be attractive for surface-enhanced Raman spectroscopy.