Catalytic effects of ferrocene on bonding, optical and structural properties of diamond-like carbon films deposited by microwave surface-wave plasma chemical vapor deposition

This paper reports catalytic effects of ferrocene on bonding, optical and structural properties of diamond-like carbon (DLC) thin films grown on silicon and quartz substrates by microwave surface-wave plasma chemical vapor deposition. For film deposition, helium and methane gases were used as plasma source. Bonding, optical and structural properties of the DLC films were measured both with and without using ferrocene as a catalyst. The ferrocene content in the DLC was confirmed by X-ray spectroscopy (XPS) measurement. The optical band gap decreased from 2.7eV (without ferrocene) to 1.6 eV (with ferrocene). Raman spectra of the ferrocene content film shows that the G-peak was more pronounced compared to the film without ferrocene. Results suggest that appropriate concentration of ferrocene in DLC film helps to reduce the optical band gap because of ferrocene-induced graphitization.