HEAD-DISK INTERFACE

As the flying height of magnetic heads decreases, the possibility of head-disk contact increases. New acoustic emission (AE) sensors for detecting head-disk contact have been developed. These devices are smaller and more sensitive than conventional ones. Using these new sensors, a method of evaluating the head-disk interface has been developed, and the influence of organic gas and dust on the head-disk interface was studied. It was found that component outgassing markedly increases the number of head-disk contacts, and can cause a failure in the head-disk interface. Wear on the slider and carbon overcoat on the disk was also studied, and the chemical change of the slider surface due to frictional heat was observed.