Molecular Spreading of Pure and Binary Mixture PFPE Nano Films on Carbon-Overcoated Disks

Due to continuous increase in areal density, the head-media spacing combining head & media overcoat, lubricant film and fly height, is expected to be less than 6.5 nm for 1 Tbits/in² hard disk drives (HDDs). The intermittent contacts between head and disk during operation are unavoidable and cause lubricant depletion in the film. Therefore, the nanoscale conformation and self-healing ability (i.e., spreading) of perfluoropolyether (PFPE) lubricant nano films is critically important in the head-disk interface to maintain long-term reliability of HDDs. In this paper, the spreading phenomena for pure and binary mixture PFPE lubricant nano films on the carbon-overcoated media were examined via molecular dynamics simulation.