Patent ID: 7092222

Claim:
An exchange coupled film comprising: a nonmagnetic or partially ferromagnetic seed layer comprising α and Cr, α being at least one of Fe, Ni, and Co; an antiferromagnetic layer; and a ferromagnetic layer, the seed layer, the antiferromagnetic layer, and the ferromagnetic layer being deposited in that order from the bottom, magnetization of the ferromagnetic layer being directed in a predetermined direction by an exchange coupling magnetic field produced at an interface between the antiferromagnetic layer and the ferromagnetic layer, wherein a Cr content of the seed layer at an interface with the antiferromagnetic layer is at least 40 atomic percent and is higher than the Cr content at another surface of the seed layer opposite to the antiferromagnetic layer, the seed layer has a region in which the Cr content gradually increases toward the antiferromagnetic layer, and a crystal structure of the seed layer at the interface with the antiferromagnetic layer is a face-centered cubic structure, and wherein grain boundaries formed in the antiferromagnetic layer and grain boundaries formed in the seed layer which appear in a cross section of the exchange coupled film parallel to a thickness direction are at least partially discontinuous at the interface between the antiferromagnetic layer and the seed layer.