Nanotribology of carbon based thin films: the influence of film structure and surface morphology

The tribological behavior of carbon based thin films is strongly influenced by their chemical composition, polycrystalline structure and surface morphology. We present friction measurements on laser deposited amorphous carbon and carbon nitride (CNx) thin films using atomic force microscopy. We studied the friction behavior of these films in relation with their structure and surface morphology resulting from the applied deposition parameters. We found high nanoscopic friction for amorphous carbon thin films, medium friction for CNx and very low friction for graphite. Finally we discuss our findings in terms of the microscopic mechanisms of energy dissipation underlying the observed friction behavior.