High performance specular spin-valve films with an FeCo-based ultrathin oxide layer by ion-assisted oxidation
Details
We compared specular spin-valve films with an Fe_<50>Co_<50> nano-oxide layer (NOL) and a Co_<90>Fe_<10> NOL in a pinned layer, prepared by natural oxidation and ion-assisted oxidation (IAO). With small oxygen exposures during the oxidation for the Fe_<50>Co_<50> NOL by IAO, good ferromagnetic coupling through the NOL and high specularity at the NOL interface were concurrently obtained. On the other hand, natural oxidation did not cause large MR enhancement for either the Co_<90>Fe_<10> or Fe_<50>Co_<50> NOLs, and the Co_<90>Fe_<10> NOL by IAO caused weak magnetic coupling through the NOL, resulting in a small MR ratio. The Fe_<50>Co_<50> NOL for small oxygen exposures is a good candidate for a final specular spin-valve film head for 100-Giga-bit per square inch recording.
