Effect of Molecular Structure of PFPE Lubricant on Interaction at HDI in Near-Contact Operation

Reduction of interactive force between magnetic head and hard disk is an important issue for maintaining the ultra-low spacing required for ultra-high recording density. The spacing would be below 5 nm for 1 Tb/in2 density. In this study, the head-disk interactive force was examined when monofunctional lubricant (that with a functional group only at one end) and difunctional lubricant (that with functional groups at both ends) were used, respectively. The study has revealed that usage of monofunctional lubricants effectively reduces the head-disk adhesive interaction at near-contact operation