Design and fabrication of ultrahigh density longitudinal and perpendicular hard disk magnetic recording heads

Single pole-type (SPT) perpendicular write heads with the use of a soft underlayer (SUL) are of current interest in the hard disk data storage community. This configuration allows for high write fields in the recording medium, which permits the use of high anisotropy media. The high anisotropy medium is required for thermal stability at ultra-high recorded densities. The study examined the effect of head parameters such as throat height and structure, return pole air-bearing surface (ABS) dimensions, yoke dimensions, and coil type (solenoid or planar). The anisotropy variance of the media was also varied. FEM simulations showed that a trade-off between maximum field and gradients is necessary due to the structure of the poletip region. Micromagnetic simulations show tribit patterns and the detrimental effect of anisotropy value variations in the media.; To make a comparison to longitudinal recording, a similarly structured longitudinal write head called a square-type head was modeled. This design has the write gap as close as possible to the write coils to provide for high longitudinal write fields. The study determined that high write fields are possible at the expense of poor downtrack gradients at low fields. By designing for a lower maximum write field, the gradients can be improved.; The fabrication of the longitudinal write head was not successful because of issues in magnetic material deposition at small dimensions producing multiple write gaps at the ABS. These issues also affected the perpendicular write heads lowering of the write efficiency.{09}The perpendicular write heads incorporated a novel multi-turn solenoid coil structure which was successfully fabricated. The limited number of samples from post-wafer processing prevented frequency performance comparison of the solenoid coil to the regular planar coil. Unfortunately the ABS was improperly fabricated on most of the sliders causing them not to fly close enough to the medium. Full head characterization was not possible, since only a one turn solenoid coil perpendicular head was found to have a working ABS. The low magnetomotive force provided by this one turn solenoid coil head in addition to the lower write efficiency limited the testing since transitions were not completely written. (Abstract shortened by UMI.)...