Thermal Stability of Magnetic Recording in Perpendicular Thin Film Media

Recording and signal decay characteristics of perpendicular CoCr-alloy thin film media are investigated in comparison with those of longitudinal media. A perpendicular medium shows recording resolution 25-32% higher than that of a longitudinal medium with similar low density output. The medium S/N of a 25nm thick perpendicular medium is comparable to that of a 16nm thick CoCrPt longitudinal medium at high linear densities. The signal decay rate of the high Mr/Ms perpendicular medium is below 0.2% per decade of time for all linear densities. These results and thermal stability considerations based on the temperature dependence of KuV/kT indicate that CoCr-alloy perpendicular recording media are promising to extend the linear density well beyond 400 kFCI. Index Terms--CoCr-alloy, perpendicular media, longitudinal media, thermal stability.