Precise Stiction Mapping

Abstract

A technique is presented for mapping the stiction on an entire disk. A map is created by measuring the stiction at predetermined points on the disk. These points are precisely located and taken in a random order to prevent any alteration of the measurement occuring from sequential movement of the slider on the disk. From this map the statistical distribution of stiction on the disk is determined. Stiction mapping is also shown to reveal nonuniformities in the physical properties of the disk. Experimental mapping results show the effect of texture and start/stop wear on stiction. A special disk was fabricated with different textures in the inner and outer diameter regions. These two textures are easily detected by a stiction map even though both had the same coating types and thicknesses. A start/stop wear experiment is performed on the outer diameter region of this disk. Precise position control is used to improve the repeatability of the stiction measurements. The stiction measured at adjacent start/stop cycles is repeatable to within ten percent, but generally increases monotonically with each cycle. This start/stop wear track is easily detected by mapping of the disk after the experiment. © 1991 IEEE