Issues in Vapor Phase Lubrication of Magnetic Data Storage Media

Vapor phase lubrication (VPL) integrates media lubrication with the vacuum processing steps used throughout most of the hard disk media fabrication process. This avoids exposure of the unlubricated a-CH_x overcoat surface to the ambient air and airborne contamination. In vapor lubrication the a-CH_x surface can be oxidized under controlled conditions immediately prior to lubricant adsorption. The kinetics of a-CH_x oxidation have been studied using x-ray photoemission spectroscopy in an apparatus that allows oxidation of freshly deposited a-CH_x films. The dissociative sticking coefficient of oxygen is ∼10⁻⁶ and the initial oxidation kinetics can be described by a Langmuir-Hinshelwood mechanism.