Experimental Study of Dual Heater Slider Touchdown Detectability

Abstract

With the increase of areal density in hard disk drive (HDD), the mechanical spacing between magnetic head and disk has decreased to sub~1nm. Under such ultra-low spacing, accurate spacing control becomes more important for lowering down the risk of head-disk interference and getting good bit per inch (BPI) performance. Dual-heater slider technology has been considered as a most useful solution. This paper introduces the advantages of dual heater in reading/writing spacing control. Furthermore, as a key issue in precise spacing control, the touchdown detectability of dual-heater slider was also investigated using three TD detection methods under writing and reading mode. Result shows that a single method is difficult to get the best TD detectability under both writing and reading mode. Instead, hybrid method may be a feasible solution.