Recording Characteristics of Co-Cr Perpendicular Magnetic Recording Media Prepared by ECR Sputtering

A sputtering using an electron-cyclotron-resonance microwave plasma was used to prepare Co-Cr perpendicular magnetic recording hard disks. The Co-Cr layer deposited under cusp magnetic field had compositional separation within Co-Cr grains. The recording characteristics of this Co-Cr disk was measured in contact sliding recording using a metal-in-gap ring head with a gap length of about 0.2 microns. D50 of 162kFRPI and low-density reproduced voltage of 100nVp-p/[turn *micron*(m/s)] was obtained. Comparing with a commercial longitudinal recording hard disk designed for inductive head whose Br•t was 289 G•microns, the ECR sputtered Co-Cr disk in cusp field showed lower medium noise and higher D50.