sp 3 /sp 2 ratio in amorphous-carbon thin film by spectroscopic ellipsometry

We introduce tetrahedral amorphous-carbon thin films, formed by reactive filtered arc deposition method, as a dielectric material for a silicon-on-insulator substrate in high-power integrated circuits. The sp3/sp2 components in the thin films were measured by spectroscopic ellipsometry, which is well known for its nondestructive and in situ characterization application. The dielectric functions of the composite materials were calculated using the Bruggeman effective medium approximation. The surface roughness was studied through atomic force microscopy. Also, the film content and thickness was studied by Rutherford backscattering.