Effect of thickness and annealing temperature on the morphology and LSPR response of bilayer Au/Ag nanostructure

This work represents a simple method for production of bilayer Au/Ag nanostructures used in localized surface Plasmon resonance sensors. Different thickness of Au and Ag were sputter-deposited on cleaned glass slides and annealed at 150°C and 300°C using an electrical furnace in ambient air for 2, 3 and 4 h. The analysis of the surface topology and optical property was performed by AFM apparatus and UV-visible spectrometer. Annealing changed appearance color of samples and red shifted the resonance wavelength. By increasment of annealing time and temperature, the resonance wavelength and the mean size of produced particles on the surface increased.