Water-repellency of a-C:H films deposited by rf plasma-enhanced CVD

Abstract

Hydrogenated amorphous carbon (a-C:H) films with high water-repellency were deposited on Si and glass substrates by rf (13.56 MHz) plasma-enhanced chemical vapor deposition using CH 4 and H 2 as raw materials. The films had a contact angle for a water drop of 94° and showed no dependence on the rf power and substrate. Thus, these films show high water-repellency due to the good hydrophobic property of the CH groups on the surfaces. The bonding structure of the films was investigated by Fourier transform infrared. The film deposited at rf 150 W showed a maximum hardness of 5.4 GPa and the optical transparency was high.