Fabrication of SmCo $_{5}$ Double-Layered Perpendicular Magnetic Recording Media

We fabricated SmCo 5 double-layered perpendicular magnetic recording media with high perpendicular magnetic anisotropy for realizing ultra high density recording. A double-layered medium with a Ru buffer layer introduced between a Cu/Ti intermediate layer and a Co-Zr-Nb soft magnetic underlayer exhibited high perpendicular magnetic anisotropy, whereas that without the Ru buffer layer did not. Auger electron spectroscopy revealed that the Ru buffer layer inhibited interdiffusion between the Cu/Ti intermediate layer and the Co-Zr-Nb soft magnetic underlayer. We report here for the first time the read-write characteristics of SmCo 5 double-layered perpendicular magnetic recording media. The medium noise was small in the medium with a Sm-Co layer deposited under high Ar gas pressure owing to small magnetic clusters