The effect of record flying height on trackedge noise in thin film media

Abstract

The effects of record spacing on trackedge noise are studied for CoCrTa and CoCrPt-CoCrTa media. Variations in record spacing (separation from magnetic media to write head pole tips) are accurately achieved by using an identical set of disks for each type of media, with different overcoat thicknesses. Trackedge noise is characterized using track profiles of the media noise. An integrated spectral technique is used to measure media noise, and the effects of the different playback spacings (separation from magnetic media to read head pole tips or read element) are removed by dividing the spectral playback loss factor from the media noise spectra. Track profiles were performed at three linear record densities for each record spacing. For both media, on-track noise and trackedge noise are found to decrease with reduced record spacing, and the amount of decrease is found to be record density dependent. However, the trackedge noise did not decrease as dramatically as the on-track noise with reduced record spacing.