Effect of van der Waals Forces in a Near Contact Head-Disk Interface

The minimum flying height, elastic deformation, and attractive pressure caused by van der Waals force under static air-bearing pressure were analyzed numerically using a spherical pad slider and a flat disk model. Parametric analysis revealed that when the pad radius of curvature was 20 mm, the minimum possible flying height was about 1 nm. The smallest roughness height, for reducing the van der Waals attractive force to less than the meniscus force, is ~ 0.5 nm.