One-Step Plasma Deposition of Platinum Containing Nanocomposite Coatings

In this paper a single step process for the synthesis of composite thin films made of platinum nanoclusters embedded in a porous hydrocarbon matrix is proposed. The process consists of a simultaneous plasma enhanced-chemical vapour deposition of ethylene and sputtering of a platinum target. Films were characterized by means of Fourier transform-infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy and transmission electron microscopy. Optical emission spectroscopy was used to investigate the plasma phase and to find correlations with the metal content of the film. The effect of radio frequency power, deposition time, and ethylene flow rate on the chemical composition and structure of the film is presented. Results show that the platinum content in the film can be controlled by tuning the power delivered to the plasma and the monomer flow rate, and that the metal aggregates in crystalline nanoclusters uniformly distributed in the material. Film morphology is characterized by columnar structures of variable diameter and orientation depending on the deposition conditions.