Production and wetting properties of fluorinated diamond-like carbon coatings

The control of hydrophobicity of diamond-like carbon (DLC) surfaces has been studied by the use of CF4 etching plasma and by the deposition of fluorinated DLC (a-C:F) using mixtures of CF4 with butane and acetylene. The results indicate that the degree of fluorination (F:C ratio), and the hydrophobicity of the surface depend critically on both the elemental composition of the gas feedstock and the deposition parameters. There is a correlation between high levels of fluorination and hydrophobicity, although at high F:C ratios, the mechanical stability of the fluorinated surface may be compromised. A possible mechanism for the production of hydrophobic fluorinated surfaces is proposed. (C) 1997 Elsevier Science S.A.