Amorphous carbon films PACVD in CH4-CO2 under pulsed and continous substrate bias conditions

This work is a comparative study of the different effects on the growth of a-C:H films obtained with the application of a pulsed and a continuous DC substrate bias. The depositions were performed at room temperature in a RF-PACVD system from a CH4-CO2 gas mixture. An external DC bias was applied to the substrate to produce an energetic ion bombardment on the growing film. Pulsing the bias turned out to be much more effective in the densification and hardening of the material than the application of a continuous negative voltage and in assuring, at the same time, better adhesion to the substrate