Ferromagnetic layered material having reliable uniaxial anisotropy

摘要

A magnetoresistive film includes a pinned ferromagnetic layer, a free ferromagnetic layer, an intermediate layer interposed between the pinned and free ferromagnetic layers, and a pinning layer contacting the pinned ferromagnetic layer. The free ferromagnetic layer is made of a ferromagnetic layered material including a cobalt nickel iron alloy layer, and a cobalt iron alloy layer laid over the cobalt nickel iron alloy layer. It has been demonstrated that the cobalt nickel iron alloy layer serves to reliably establish the uniaxial magnetic anisotropy in the cobalt iron alloy layer. Moreover, even if the thickness of the cobalt nickel iron alloy layer as well as the cobalt iron alloy layer is reduced, the uniaxial magnetic anisotropy can surely be maintained in the ferromagnetic layered material.