High-resolution magnetic force microscopy study of high-density transitions in perpendicular recording media

Abstract

High-resolution magnetic force microscopy (hrMFM) has been used to investigate the write characteristics of forward and reverse flying heads on perpendicular recording media with soft underlayers. hrMFM has the advantage that it provides much better resolution than the read element of a head, particularly in the cross-track direction. Using a quantitative analysis method, many parameters, such as transition position jitter, transition width and signal-to-noise ratio are estimated from the hrMFM image. Furthermore, these parameters, which can also be measured using a spinstand, are compared to the micromagnetic properties of the transitions, such as track curvature, transition width and the local noise associated with transitions. The results give insights into the recording physics and, in particular, in the write process of shielded and un-shielded write heads in perpendicular recording.