Partially oxidized Fe-Co medium with perpendicular anisotropy

Partially oxidized Fe-Co films prepared by reactive RF magnetron sputtering have a large perpendicular anisoptropy and large saturation magnetization. A segregation into two phase of metal and oxide was observed by X-ray photospectroscopy (XPS), X-ray diffraction (XD), electron diffraction (ED) and Mossbauer spectroscopy. Metal phase is of bcc structure and oxide is NaCl type cubic structure (wustite). Metallic fibers line up perpendicularly and are surrounded by oxide. We conclude that the shape effect is the origin of the perpendicular anisotropy. High density recording is also demonstrated by using the partial oxidized medium with soft magnetic layer with combination of perpendicular head.