Patent ID: 7782576

Claim:
An exchange-coupling film comprising an antiferromagnetic layer and a pinned layer that are stacked, the pinned layer having a fixed direction of magnetization, wherein: the pinned layer includes a first ferromagnetic layer, a second ferromagnetic layer, a third ferromagnetic layer, a nonmagnetic middle layer, and a fourth ferromagnetic layer that are disposed in this order, the first ferromagnetic layer being closest to the antiferromagnetic layer; the first ferromagnetic layer is made of a ferromagnetic material and has a face-centered cubic structure; the second ferromagnetic layer is made of only iron or an alloy containing x atomic % cobalt and (100−x) atomic % iron, wherein x is greater than zero and smaller than or equal to 60; the third ferromagnetic layer is made of an alloy containing y atomic % cobalt and (100−y) atomic % iron, wherein y is within a range of 65 to 80 inclusive; the nonmagnetic middle layer is made of a nonmagnetic material; the fourth ferromagnetic layer is made of a ferromagnetic material; the antiferromagnetic layer and the first ferromagnetic layer are exchange-coupled to each other; and the third and fourth ferromagnetic layers are antiferromagnetically coupled to each other.