Flying Height Measurement on Al2O3 Film of a Magnetic Slider

Abstract

Flying height has been successfully measured on the Al2 O3 film of a magnetic slider by using a specially developed ellipsometer, a reflectometer, and an intensity based interferometric flying height tester. The accuracy of the measured flying height values has been verified with a profilometer. It is found that, under certain conditions, the flying height value generated by the currently used methodology in the hard disk drive industry is misleading in the sense that it can be significantly different from both the true gap and the minimum flying heights. Therefore, it is proposed that the flying height measurement methodology reported in this study be used by the hard disk drive industry to correctly measure the gap and minimum flying heights.