CHARACTERIZATION OF MAGNETRON-SPUTTERED DIAMOND-LIKE THIN-FILMS FOR OPTICAL COATINGS IN IR

The microstructural, optical, mechanical and electrical properties of diamond-like carbon films prepared by d.c. magnetron sputtering have b een investigated as a function of argon pressure and substrate bias. T he films were characterized by spectroscopic ellipsometry, scanning an d transmission electron microscopy, electron diffraction, resistivity and hardness measurements. The pseudoband gap was found to rise and th e hardness decrease with increasing pressure. Ellipsometric modelling indicated a change in the bonding configuration under the above condit ions. This effect does not appear to be the result of a change in the energetics of the bombarding ions. Increasing substrate bias resulted in a densification of the films.