NANOTRIBOLOGICAL EVALUATIONS OF HYDROGENATED CARBON-FILMS AS THIN AS 5-NM ON MAGNETIC RIGID DISKS

Nanotribological characterization techniques including nano-wear tests and nano-friction tests are used to evaluate mechanical and tribologi cal properties of 5, 10 and 25nm thick hydrogenated carbon films depos ited as protective coatings on super smooth magnetic disks. Effects of film thickness and substrate materials are investigated. It is found that the film with a higher thickness has a larger critical cycle for film break-through. The 5nm thick film has the smallest wear depth bef ore the critical cycle, the largest critical load for wear, and the la rgest friction coefficient in the low friction regime. No significant differences are observed between the 10nm and 25nm thick films with re spect to these three parameters. The film on the magnetic layer is rem oved with fewer wear cycles than on the silicon substrate. But the eff ect of substrate is not significant on the wear depth before the criti cal cycle, the critical load for wear initiation, and the friction coe fficient in the low friction regime.