Structure and chemical composition of thin-film nanocomposites based on silver in organosilicon amorphous matrix prepared by High Target Utilization Sputtering

Abstract

Thin films based on Ag nanoclusters embedded in an organosilicon polymer matrix were deposited using the High Target Utilization Sputtering technique (HiTUS) by simultaneous sputtering of the Ag target and polymerization of hexamethyldisiloxane (HMDSO) vapors in radiofrequency plasma. The influence of deposition parameters on chemical composition and structure of the deposited nanocomposite films was studied using scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray diffraction analytical techniques. The films under investigation exhibit a dense uniform structure with the metallic nanocrystalline silver present in the form of spherical-shaped nanoclusters with dimensions below 10 nm embedded in an amorphous organosilicon plasma polymer. The average size of Ag nanoclusters is increased from 1.8 to 4.4 nm with Ag content increasing from 16 to 57%at. while concentration of nanoclusters is reduced. Incorporation of the metallic silver into the plasma polymerized HMDSO leads to a decrease of carbon and oxygen content as well as a decrease of organosilicon polymer matrix density.