Roughness and porosity characterization of carbon and magnetic films through adsorption isotherm measurements

Abstract

Hard carbon films are receiving much current attention on account of their potential use as protective overcoats. The tribological properties have an important influence on the functional performance of the films and can be probed through studies of film porosity and roughness. The technique of adsorption is particularly advantageous for this type of investigation because the area coated by an adsorbed monolayer is precisely that involved when the protective coating is exposed to the atmosphere. Adsorption studies have been carried out for both carbon and magnetic thin films which have been deposited onto the surface electrodes of quartz-crystal microbalances. These studies provide (i) an immediate determination of whether the film is rough or porous, and (ii) if porous, an indication of pore morphology. © 1989, American Vacuum Society. All rights reserved.