HDI-17 Improvement of DLC overcoat by controlling hydrogen content and its application to lower flying height hard disk medium

Abstract

The relation between hydrogen contents in DLC overcoat of a hard disk medium and its head flyability was studied. The effect of additional gasses such as N_2 and N_2O was also investigated. It was found that the hydrogen content in DLC affects the magnetic head flyability and it is effective to add N_2O in the atmosphere of DLC deposition process not only to obtain sufficient amount of functional groups but also to reduce hydrogen content of the DLC overcoat. The results of glide test showed drastic improvement of head flyability by decreasing the hydrogen/carbon ratio.