Yoshiharu Kasamatsu

Stiction free slider for the smooth surface disk

We describe the superior tribological performance for a slider with three cylindrical pads on the air bearing surfaces on a smooth surface disk. Using photolithography, we can form the cylindrical pads with a controlled surface area and uniform height on the air bearing surfaces of a magnetic head. In addition to the reduction of the apparent contact area of the head/disk interface, by applying an excessive amount of lubricant to the vertical surface of the pads, we can lower the static friction with an ultra smooth surface (Ra=0.3 nm). Moreover, we observed no wearing of the pads after 100,000 CSS cycles.

Stiction free slider for lightly textured disks

We developed a Stiction Free Slider that has pads on the air bearing surface to reduce the stiction between the head and disk. This paper presents our extended experimental data on the SFS for use on lightly textured disks. The SFS shows excellent CSS performances on disks having an average roughness of 0.8 nm with 1.5 -2.5 nm thick lubricant. The wear of pads is negligible after 100,000 Contact Start/Stop cycles. This novel technique has an excellent potential to overcome the tribology obstacle and thus enable ultra high density recordings.

Chemically modified air-bearing surface for the near-contact regime

A chemically modified air-bearing surface (ABS) was experimentally investigated. Its surface energy was lowered by bonding nonpolar lube to the surface using ultraviolet light. The altered surface was shown to decrease the van der Waals force and to have good flyability under a 10-nm flying height (FH).

Chemically modified air-bearing surface for the near contact regime - part 1: concept and characterization

In order to increase the areal density of hard disk drives, it is crucial to reduce the physical spacing between the read-write head and the magnetic layer. Currently, the head-disk clearance decreases to less than 10 nm. At such a clearance the thickness of the lubricant on a hard disk contributes more than 10% of the clearance. Consequently, the lubricant pickup phenomenon becomes a serious problem. One solution for achieving good flying ability under 10 nm would be to lower the surface energy of the air-bearing surface of the slider. Reducing the surface energy of ABS provides the promise of good flying ability. In order to confirm an improvement in slider performance, take-off velocity (TOV) was examined. As a result, TOV changed roughly from 3000 rpm to 2000 rpm. The subsequent paper shows improvements in the sliders performance.