McDermott, Will & Emery
Patterning of high coercivity magnetic media by ion implantation
A servo-patterned magnetic recording medium, comprising:a magnetic layer having a surface with substantially uniform topography, the magnetic layer including a data zone and a servo pattern, the servo pattern comprising:(a) a first patterned plurality of regions of first, higher values of magnetic coercivity Hc and magnetic remanence-thickness product Mrt; and(b) a second patterned plurality of ion-implanted regions of second, lower values of Hc. and Mrt; wherein the second, lower values of Hc and Mrt are sufficiently lower than the first, higher values of Hc and Mrt as to permit sensing for enabling accurate positioning of a read/write transducer head in the data zone but sufficiently high for providing the medium with thermal stability, high amplitude of magnetic transition, and high signal-to-noise ratio.
Seagate Technology LLC
B G G G G
B82Y G11B G11B G11B G11B
inventional inventional inventional inventional inventional
David S. Xinwei
Kuo Li