Deposition of Amorphous-Carbon Films by RF Plasma CVD Method

Amorphous-carbon films were deposited by the RF plasma CVD method from hydrocarbon gases. Two types of properties were observed in respective films by changing pressure, flow rate and source gas species ; one film was hard with an amorphous structure, while the other was soft with a graphite-like structure. The highest deposition rate of hard film was 0.8 μm/h. The effect of the gaseous reactions on deposition rate and properties of films in the RF plasma were studied by using in-situ FT · IR and OES analyses. The results showed that the film properties were affected by the residence time of reactant gases. In particular, higher concentration of acetylene (≥ 2.3×1014 cm-3) was a cause of growth of soft, graphite-like films.