Investigation of Amorphous Silicon-Carbon Films Deposited by Filtered Vacuum Cathodic Arc
Amorphous silicon-carbon films have been successfully deposited by the filtered cathodic vacuum arc techniques. One set of films was deposited from varying silicon-carbon composition in the targets and another set of films was deposited at different various substrate bias voltages from 5 at.% silicon target. The properties of the film were investigated by using atomic force microscopy (AFM), Raman spectroscopy, x-ray photoelectron spectroscopy (XPS) and contact angle measurement. The first set of the samples exhibit atomic smooth surface morphology with RMS roughness below 0.26 nm. The silicon composition in the films determined by XPS varies from 0 to 61 at.%. The Raman results show that at low silicon composition, the G peak position of C-C bond shifts to a low wavenumber, that demonstrates the silicon atom predominantly substitutes for the carbon atom. As the silicon composition increase, the G peak disappeared and a strong broad peak corresponding to the amorphous silicon carbide cluster appears around 800 cm-1. For the second set, the Raman results show the ID/IG ratio increased from 0.24 to 0.67 with using the high bias voltages during the deposition. That indicates the disorder of C-C bond within the films increased. While, both the silicon concentration in the films and contact angles remain relatively constant with the change of bias voltage.
M. Gupta and Christina Y.H. Lim
P. Zhang et al., "Investigation of Amorphous Silicon-Carbon Films Deposited by Filtered Vacuum Cathodic Arc", Journal of Metastable and Nanocrystalline Materials, Vol. 23, pp. 351-354, 2005