Fly-height, pitch, and crown measurements of hard-disk sliders by capacitance stripe

The capacitance-stripe technique uses a special disk and high-speed capacitance amplifier to yield profiles of the air-bearing surface of a flying slider. The author reports extensions of the technique to make it more applicable to modern low-flying sliders. These include a more planar substrate, an amplifier less sensitive to large lead impedances, and the use of a difference measurement to account for the nonuniform rail-widths of some modern sliders. Results of fly height, pitch, and crown measurements are close enough to interferometric measurements of these quantities to encourage the use of capacitance stripe as a low-cost alternative technique. Landing measurements on an IBM 3390-type slider show the slider tipping forward on landing owing to frictional torques