Microstructure and mechanical properties of nanocomposite amorphous carbon films

Nanocomposite amorphous carbon films such as a-C:Al, a-C:Ti, and a-C:Si have been prepared using a filtered cathodic vacuum arc technique. The films were characterized using x-ray photoelectron spectroscopy (XPS), atomic force microscopy, surface profilometry, a nanoindenter, and Raman spectrometry. It was found that metal contents in the films deviate from the target depending on the constituent element, which is attributed to the effect of dynamic balance deposition. XPS results revealed the presence of a carbide phase in a-C:Ti and a-C:Si but not in a-C:Al nanocomposite carbon films. Incorporating metal into amorphous carbon films significantly reduces the compressive stress but maintains the relative high hardness and Young’s modulus.