Co-Pt-TiO/sub 2/ composite film for perpendicular magnetic recording medium

A new type of oxide composite film was proposed as perpendicular magnetic recording medium. The storage layer is composed of Co-Pt and Ti-oxide. By transmission electron microscopy (TEM) observation, the film exhibited a well isolated fine granular structure with small and uniform Co-Pt grains surrounded by TiO/sub 2/. More sufficient segregation by TiO/sub 2/ was realized from the beginning of the layer growth compared with other oxide addition film, resulting in a magnetically weak coupled structure. This film has a relatively large magnetic anisotropy constant (K/sub u/) and saturation magnetization (M/sub s/) of more than 5/spl times/10/sup 6/ erg/cm/sup 3/ and about 800 emu/cm/sup 3/, respectively. The structure was brought about by a high sputtering gas pressure of Co-Pt-TiO/sub 2/ film deposition.