Tribology of proximity magnetoresistive head-disk interface for 5 Gb/in.(2) recording

Low fly-height magnetoresistive (MR) sliders and low glide-height laser-tex ture thin film disks were introduced to meet the tribological challenges of proximity MR recording, with which an areal density of 5 Gb/in.(2) has bee n achieved when using the sliders with dual-stripe MR heads and the disks w ith low-noise media. The 30% pico sliders employed two air-bearing designs with a fly height around 12.5 nm. The thin film disks used superfinish subs trates with a glide-avalanche-height falling well below 10.0 nm. In the con tact start/stop (CSS) zones, small crater-shape laser texture bumps were ge nerated to meet both low stiction and low glide-height requirements. An 80 Angstrom thin amorphous nitrogenated carbon was added over the magnetic lay ers as a protective overcoat. A layer of perfluoropolyether with an additiv e of phosphazene compounds was applied on the disk surface to improve the r eliability of head-disk interfaces. The near contact head-disk interface su rvived for 20 k-cycle hot/wet and hot/dry CSS tests without wear and high s tiction. Twenty-four-hour hot/wet park-stiction values after 20 k CSS cycle s were within the acceptable range. Remarkably, thermal-asperity tests show ed no hits by using the proximity heads on the ultralow glide-height thin f ilm disks. (C) 1999 American Institute of Physics. [S0021-8979(99)71608-7].