ENHANCEMENT OF HEAD-DISK INTERFACE DURABILITY BY USE OF DIAMOND-LIKE CARBON OVERCOATS ON THE SLIDERS RAILS

Al2O3-TiC sliders used in magnetic recording hard disk drives were coa ted with diamond-like carbon (DLC) to improve the wear durability of t he head-disk interface (HDI). Both contact-start-stop and constant spe ed drag tests were conducted during which the build up of friction ass ociated with wear of the thin film disks was measured in a standard di sk wear tester. The friction values increased three or fourfold in the tests with uncoated sliders, whereas tests conducted with DLC coated sliders showed only a twofold increase in friction in the early part o f the test followed by constant friction values afterwards. This major improvement was found for as little as 7 nm of coating on the sliders . Increases of wear durability of the head-disk interface by factors o f 50-200 were obtained.