The influence of different ratio of Ar and CH66 gases and ion bombardment on the growth rate and sp3 bonds content in DLC-coatings synthesized in RF discharge

The radio-frequency discharge growth of diamond-like carbon coatings from the Ar + C6H6 gas was theoretically analyzed with the aim to evaluate the role of Ar+ ions and C6H6+ ionized molecules bombardment on the growth rate and sp2/sp3 carbon phase composition. It has been shown that the growth rate changes nonlinearly with the increase of argon content in the gas. Firstly, it increases from 1.9 μm/h at PAr/(PAr+Pbenzol)=0.033 up to 2.15 μm/h at PAr/(PAr+Pbenzol)=0.5 with further rapid decrease down to 0.57 μm/h at PAr/(PAr+Pbenzol)=0.967. By using theoretical calculations as well as experimental methods it has been shown that sp3 content in the coatings increases within the range 0.31…0.41 with increase in the relative partial pressure of argon.