Optical Properties of DLC:SiO_x and Ag Multilayer Films: Surface Plasmon Resonance Effect

Diamond like carbon films containing silicon (DLC:SiOx) and "conventional" hydrogenated diamond like carbon (DLC) films were deposited by direct ion beam using anode layer ion source. Ag films were grown by unbalanced direct current magnetron sputtering. Structure of DLC:SiOx films was investigated by Raman scattering spectroscopy. In the case of DLC:SiOx film deposited on Ag layer surface enhanced Raman scattering effect was observed. Optical properties of the different diamond like carbon and silver multilayers were studied. Annealing effects were investigated. Influence of the thickness of the diamond like carbon and Ag layers was investigated. Position of the plasmonic absorbance peak maximum of DLC:SiOx and multilayers in all cases was redshifted in comparison with "conventional" diamond like nanocomposite films containing silver nanoclusters. It was explained by increase of the Ag nanoparticle size and/or increased probability of the oxidation of the embedded Ag due to the higher amount of oxygen in DLC:SiOx film in comparison with "conventional" diamond like carbon film