Preparation of Co-Cr-Ta Hard Disk High Density Recording Media

In order to improve the anisotropy field distribution of Co-Cr recording media, the effect of Ta addition was investigated. It was found that by adding Ta the initial Co-Cr layer with poor crystal orientation is eliminated, and crystal orientation and crystallinity are drastically improved. It was also confirmed that the anisotropy field distribution of the Co-Cr-Ta layer is narrowed to one-third that of the Co-Cr layer. To clarify the effect of Ta addition on recording characteristics, Co-Cr-Ta/Nb-permalloy double-layer media were prepared and their recording characteristics were measured. The Co-Cr-Ta media showed a sharp magnetization distribution and higher reproduced voltage at high densities than did the Co-Cr media.