PFPE Lubricant Bonding to Carbon Overcoats

Continued reduction in the head-disk spacing of magnetic data storage systems and the resulting increase in the frequency of head-disk contacts will place increasing burdens on the perfluoropolyalkyl ether (PFPE) lubricant and amorphous carbon (a-C) overcoat used to protect the surfaces of magnetic media. In addition, environmental conditions such as temperature, humidity, and contamination that influence the lubricant-overcoat interactions become increasingly important to the tribological performance of the head-disk interface. It is of utmost importance to obtain a fundamental understanding of the molecular interactions at the lubricant-overcoat interface in order to maintain the reliability of future hard disk drives. Recent progress has generated insight into the heterogeneous nature of the a-C overcoat surface, the interaction mechanisms of PFPEs with a-C overcoats, the effects of humidity on lubricant-overcoat interactions, and the evaporation kinetics of PFPE lubricants.