Reactive ion etching (RIE) ofa‐SiC:H thin films in a CCl4/O2plasma has been investigated. The effects of process parameters, in particular radio‐frequency power, oxygen addition, gas flow rate, interelectrode spacing, and pumping speed, ona‐SiC:H etch rate anda‐SiC:H/oxide etch selectivity are reported. For the RIE ofa‐SiC:H in CCl4/O2plasmas, the gas phase plasma chemistry and surface reactions appear to be more important than ion bombardment. Reactive species generated from neutral chemical reactions of oxygen in the discharge play a more dominant role than those generated from the electron impact dissociation processes.