Kinetics of plasma-assisted chemical vapor deposition combined with inductively excited RF discharge and properties of a-C:H:SiOx coatings

Abstract

The paper studies the plasma-assisted chemical vapor deposition of a-C:H:SiOx coatings in plasma of non-self-sustained arc discharge with a hot cathode combined with inductively excited radio-frequency (RF) discharge. The a-C:H:SiOx coatings are produced by polyphenyl methylsiloxane (PPMS) dissociation in plasma with and without RF discharge. The optical emission spectroscopy is used to study the PPMS dissociation process. Raman spectroscopy provides the structural investigations of the obtained coatings, while the energy dispersive X-ray spectroscopy is used to analyze the chemical composition. It is shown that the mechanical and tribological properties of a-C:H:SiOx coatings depend on the RF discharge power and the bias voltage amplitude of the substrate. It is demonstrated that substrate bias voltage can be reduced during the coating deposition in combined discharge without significant degradation of its mechanical and tribological properties due to the better dissociation and ionization of PPMS vapor molecules in inductively excited RF discharge.