Interface stability study towards ultra-high density magnetic recording

Abstract

Information storage technology is the backbone technology of the modern information society. Magnetic disk drive is the major information storage device. One critical challenge for modern magnetic disk drive is the ability to achieve stable and small spacing between the data read/write head and data storage media which allows stable signal to be read and written on the media. This thesis investigates the stability associated with the head-disk interface for future ultra-high density magnetic recording. Currently, the areal density of the top level magnetic disk drives is around 120 Giga-bit per square inch (Gb/in2). The work reported in this thesis is targeted at the technology required for 1000 Gb/in2 (or 1 tera-bit per square inch) of areal density and beyond, which requires a head-disk physical spacing or flying height of the head-slider of about 3.5 nm or below. One significance effect of such small spacing is that the short range surface interaction forces such as the intermolecular force, the lubricant-induced meniscus force and the electrostatic force become comparable in magnitude to the slider air bearing force. As a result, the spacing or flying height stability becomes a severe concern.