Structure and hardness of a-C:H films prepared by middle frequency plasma chemical vapor deposition

▶ The effect of precursors of CH4 and C2H2 + H2 on the structure of a-C:H films is investigated. ▶ The a-C:H films from CH4 precursor is DLCH, while for C2H2 + H2 precursors is PLCH. ▶ These two types a-C:H films show also opposite evolution trends with bias voltage increasing.