(Fe-Co/Si)/sub n/ multilayers with high saturation magnetization for backlayer of perpendicular magnetic recording media

Summary form only given. A storage layer with high perpendicular coercivity (H/sub c/spl perp//) is essentially required to achieve high recording density with high bit stability for perpendicular magnetic recording media. A new material with large 4/spl pi/M/sub s/ above 20 kG must be developed for a soft magnetic backlayer (BL) beneath the storage layer as well as a writing head material (T. Osaka et al, 1998) for keeping away deterioration of the writing field gradients by saturation of the BL. In this study, (Fe-Co/Si)/sub n/ multilayers with large 4/spl pi/M/sub s/ as well as low coercivity are introduced. Domain structure and soft magnetic characteristic of (Fe-Co/Si)/sub n/ multilayers (ML) were compared with those of the other BL materials to clarify their suitability for BL in perpendicular recording media.