Electrical and structural characterization of DLC films deposited by magnetron sputtering

In this work diamond-like carbon (DLC) films were deposited by d.c. magnetr on sputtering using a graphite target and argon as the discharge gas. Hydro gen gas was introduced in the discharge chamber to produce hydrogenated DLC films. By increasing the hydrogen flow from zero to 22% of the total flow, the following modifications of the film properties were observed: a decrea se in the r.m.s. roughness (from 0.45 to 0.21 nm); an increase in the elect rical resistivity (from 5 x 10(6) Ohm cm to 2.5 x 10(8) Ohm cm), while the relative dielectric constant remained almost constant at about 3.3. Increas ing the substrate temperature, we observed a logarithmic decrease of the el ectrical resistivity of the films, caused by a self-annealing process of th e DLC film during the deposition. This decrease was faster for the hydrogen ated films, due to the additional effect of the dehydrogenation. The Raman spectra analyses of these films are in agreement with these observations. ( C) 2001 Kluwer Academic Publishers.