Triboelectrification of nano-gap giant magnetoresistive heads during high revolutions per minute glass disk rotation

Abstract

Contact electrification or Triboelectrification is a well-known phenomenon when two materials of different work functions come into contact and separate. Head Disk Interfaces or HDI between sensor and disk platters has been decreasing in the past years approaching nanometer levels. HDI is also called Flying Height in storage technology terms. The extremely small space between the two objects may likely cause scratching, smearing, increase in air pressure between the disk and head, and therefore increases the problem of contact electrification. This is even problematic for Flying Height Test or FHT testing, when the procedure uses insulated glass rotating at 10,000 rpm. In this study, contact electrification was measured using actual heads mounted on Head Gimbal Assembly (HGA) on Flying Height Testers. A model was attempted to describe the phenomena of contact electrification during Flying Testing.