The microstructure and intergranular coupling in Co85.5Cr10.5Ta4 and Co78Cr17Ta5 media fabricated using an ultraclean (UC) process are discussed in relation to the thickness of the Cr underlayer. The purification of the deposition atmosphere by applying the UC process is found to be most effective for deriving high Hc in both media. In UC-Co78Cr17Ta5, a high Hc of about 2.1 kOe remains even at a Cr thickness of 2.5 nm. With the UC process the Cr segregated grain boundary structure is enhanced even in media with thin Cr underlayers, which causes a remarkably low intergranular exchange coupling. The increase in the strength of intergranular magnetostatic coupling due to the grain size reduction strongly influences the reduction in Hc/Hkgrain with decreasing Cr thickness. In UC-Co78Cr17Ta5 with extremely thin Cr underlayers, the sufficiently segregated grain boundary structure and the intrinsically low intergranular magnetostatic coupling are responsible for the realization of very high Hc/Hkgrain.
|ジャーナル||Journal of Magnetism and Magnetic Materials|
|出版ステータス||Published - 1996 1 1|
|イベント||Proceedings of the 1995 6th International Conference on Magnetic Recording Media, MRM - Oxford, UK|
継続期間: 1995 7 16 → 1995 7 19
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics