The study of structure and optical properties of Nanoparticles(NPs)-Cu/SiO₂ multilayer films deposited alternately by magnetron sputtering technique

NPs-Cu/SiO₂ multilayer films were deposited alternately by magnetron sputtering on single silicon and Corning glass substrate with different Cu target power at room temperature (RT) and 400 °C. The structure of the NPs-Cu/SiO₂ films was analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optical absorption property was investigated by Ultraviolet–visible spectroscopy (UV–Vis). The results of XRD and TEM indicate that Cu nanoparticles are basically spherical and disperse in the SiO₂ matrix. The optical absorption peaks due to the surface plasmon resonance (SPR) of Cu nanoparticles are observed in the wavelength range of 590–650 nm. The SPR peak for NPs-Cu/SiO₂ multilayer films shows the red-shift trend with increasing Cu target power, however, the SPR peak shows the blue-shift trend with increasing the substrate temperature and the number of Cu layers