Adhesion and Friction Evaluation of Textured Slider Surfaces in Ultra-Low Flying Head-Disk Interfaces

Abstract

To achieve extremely high-density magnetic recording of 1 Tbit per square inch using conventional technologies, the distance between the recording slider and the rotating disk needs to be less than 5 nm. For successful operation, disk and slider surfaces must also be extremely smooth with root-mean-square roughness values of few angstroms. However, ultra-low flying super smooth head-disk interfaces may be exposed to a significant amount of intermittent contact, adhesion, stiction and friction that can cause the interface to collapse. In order to circumvent such problems, many novel techniques have been proposed, such as laser zone texturing, contact pads and surface microtexturing. A reliable method to reduce adhesion and friction in ultra-low flying head-disk interfaces is to control the area of contact and roughen the interface, which allows the slider to fly at sub-5 nm with minimal contact. A technique known as preferential texturing provides a unique roughening of the air-bearing surface, where parts of the surface are removed, i.e., subtractive texturing process. In this paper, the effect of preferential texturing (roughening) of slider air-bearing surfaces on the adhesion and friction forces are investigated using quasi-dynamic models. The simulation results show that surface texturing reduces adhesion and friction by reducing the effective area of contact between the slider and media surfaces and by preferentially roughening the interface. The simulation results of friction compare favorably with experimental data.

The Effect of Oil Pockets Shape and Distribution on Seizure Resistance in Lubricated Sliding

“…The surface texturing of slider surface can reduce adhesion and friction by reducing the contact area [32].…”

Surface Texture Effect on Friction of a Microtextured Poly(dimethylsiloxane) (PDMS)

“…Many studies have shown that surface textures can retain oil and entrap wear particles [7][8][9]. For hydrodynamic lubrication in particular, surface textures may support the formation of lubricating oil film [10][11][12][13].…”

Experimental and theoretical evaluation of friction at contacting magnetic storage slider–disk interfaces

“…Several techniques have been introduced to reduce the contact area of these low flying slider-disk interfaces in an effort to reduce friction: texturing air-bearing surface (ABS) [6][7][8], adding small contact pads on the slider surface [4,9], and texturing to the disk surface. While these techniques reduce friction substantially, further reduction is needed to ensure that occasional contacts do not have a detrimental impact on disk drive operations.…”