Fabrication of ultra high density ferromagnetic column arrays by porous alumina template for magnetic recording media

In this paper, we succeeded in the fabrication of Co columns that had perpendicular anisotropy with density of 800 Gbit/inch/sup 2/. The proposed method for realizing the high-density magnetic recording media is suitable for obtaining perpendicular anisotropy, since the anisotropy can be controlled by changing the aspect ratio of the magnetic columns. For realizing ferromagnetic column array with higher recording density, filling of ferromagnetic materials in the porous alumina nanoholes formed at anodic voltages lower than 10 V is essential, and further study is in progress.