| 摘要 |
A cobalt alloy disk for horizontal magnetic recording has both high coercivity and low noise at high recording density. The magnetic layer in the disk contains, in addition to the cobalt alloy material, an oxide of one or more "impurity" elements which have both a relatively low solubility in cobalt and a high affinity for oxygen. Such elements include yttrium (Y), silicon (Si), the rare earth elements, hafnium (Hf), germanium (Ge), tin (Sn) and zirconium (Zr). The disk may be formed by co-sputtering the cobalt alloy material and the impurity element(s), and thereafter oxidizing the impurity element(s). The oxidation may occur by heating the disk while the magnetic layer is exposed to oxygen or air, or by exposure of the magnetic layer to an argon-oxygen plasma. |
