Influence of Intermolecular Force on the Head-Disk Interface of HDD with High Recording Density

As the recording density of hard disk drive (HDD) increases at a high rate, the clearance between the slider and disk has decreased to several nanometers. Studies showed that the flying height of hard disk head should be less than 3.5 nm in order to achieve a magnetic recording areal density of 1 Tb/in². For the two solid surfaces of slider and disk with such a small space, it is reasonably that the surface forces should be taken into account to determine the hard disk head flying status accurately. In this paper, a model of the intermolecular force between the slider and disk is constructed, and then the influences of the intermolecular force on head-disk interface, such as the thickness of the lubricant film, the pitch angle, the roll angle and the air bearing surface, are analyzed in detail. Numerical simulation results show that, in order to reduce the influence of intermolecular force, the lubricant film thickness, the pitch and roll angle should be increased, and the trailing pad of the slider should be reduced if the condition permits. This provides a theory basis for the design of slider of HDD with high recording density.