Diamond-like carbon (DLC) films were deposited on p-type (100) Si wafers using a plasma-enhanced chemical vapor deposition system and their structural bonding characteristics and mechanical properties were investigated as a function of the mixture ratio of methane-hydrogen gas and the bias voltage. It was found that the deposition rate increased with an increase in the flow rate of methane in the gas mixture and an increase in bias voltage. The sp3/sp2 ratio of carbon in the films and the hardness of the films increased with an increase in the flow rate of hydrogen in the gas mixture and an increase in the bias voltage.

Keywords: Diamond-like carbon, PECVD, Bonding structure, Hardness