Investigation of tribological and read-write performance of textured sliders
Slider surface texturing is a promising new way to improve the tribological performance of future hard disk drives with very low flying heights. In this study, proximity recording sliders with a design flying height of 6 nm at 20 m/s were textured using oxygenated plasma etching. In order to protect the read-write element, texturing of sliders was performed after positioning a mica mask over the read-write element. The tribological and read-write performance of the slider before texturing was compared with the tribological and magnetic performance of the same slider after texturing. It was found that no degradation of the read-write performance occurred and that the tribological performance of the slider was improved after texturing.
Development of contact sliders with nanotextures by femtosecond laser processing
This paper describes the development of novel contact sliders with nanotextures by means of femtosecond laser processing. In order to achieve a magnetic recording density of more than 1 Tb/in2, it is necessary to create an ultralow head-disk interface (HDI) spacing, i.e., less than 2–3 nm. Thus far, various new concept HDI technologies have been proposed for developing such near-contact or contact recording HDI. In this paper, the authors propose the concept of a novel contact slider. This slider has nanotextures fabricated by femtosecond laser processing. Sliders with five DLC thin-film pads on the air bearing surfaces were used, and the pad diameter and thickness are 40 μm and 40 nm, respectively. The fabrication process of nanotextures on the DLC thin-film pads employed a femtosecond Ti:sapphire laser. The laser wavelength and pulse width are 800 nm and 120 fs, respectively. Contact slider experiments were also carried out, using (1) the fabricated contact sliders having nanotextures with different RMS heights and (2) a contact slider without nanotextures. The nanotribological characteristics of the contact HDI as well as the dynamics of the contact sliders were investigated. In addition, the behavior of the ultrathin liquid lubricant film was evaluated by using a surface reflectance analyzer (SRA) after the contact slider experiments. It was found that the nanotextures produced by femtosecond laser processing are very effective for next-generation contact sliders and the optimum RMS heights of the nanotextures can be obtained. These advancements will facilitate the development of contact HDI with lower friction, lower wear of the contact slider surfaces, smaller change in the lubricant film thickness and lower contact slider bouncing vibration.
An Experimental Study of the Parameters That Determine Slider-Disk Contacts During Dynamic Load-Unload
The parameters that appear to determine if slider-disk contact occurs during dynamic loading are the relative loading velocity at the instant of load and the initial pitch and roll of the slider at its unloaded state. A dual-beam LDV system is employed in this study to measure the displacement, pitch, and roll during dynamic loading for five different standard 3380-type sliders in order to investigate the effects of the initial pitch and roll. The effects of the initial height and control loading speed are also examined by using the dual-beam LDV and acoustic emission (AE)