Fluorine incorporation into hard amorphous hydrogenated carbon films deposited by pecvd

摘要

The incorporation of fluorine into amorhpus hydrogenated carbon films deposited by the plasma enhanced chemical vapor deposition technique (PECVD) was investigated. Different mixtures of CH_4 and CF_4 were employed as the plasma atmosphere, with the partial pressure of CF_4 ranging from 0 to 100percent. For all depositions, the self-bias was kept at -350 V. In the case of atmospheres richer than approx 80percent of CF_4, no film deposition but substrate erosion was observed. The composition of the films was determined by Ion Beam Analysis (IBA), revealing that fluorine is incorporated into the amorphous network by replacing hydrogen. Infrared (IR) transmission measurements confirmed these results. It was also found that the incorporation of fluorine has the effect of reducing both the internal stress and hardness due to atomic density reduction.