Synthesis of DLC films with different sp2/sp3 ratios and their hydrophobic behaviour

Diamond-like carbon (DLC) films were deposited on glass substrate by sputtering of a vitreous carbon target in Ar + H-2 plasma. The sp(2)/sp(3) content in the films depended on the relative amount of hydrogen in the Ar + H-2 plasma. The films were characterized by Fourier transformed infrared studies, Raman studies, scanning electron microscopy, atomic force microscopy and optical measurements. Hydrophobicity in these films was studied by measuring the contact angles of the water droplets and it was found that the films were extremely hydrophobic. The results are interpreted in terms of hybridization of carbon in these DLC films.