Patent ID: 8194364

Claim:
A magnetoresistive effect element (MR element) that is a giant magnetoresistive effect element in a current perpendicular to plane (CPP-GMR) structure, comprising: a spacer layer; a first ferromagnetic layer and a second ferromagnetic layer that are laminated to sandwich the spacer layer, in which a sense current flows along a lamination direction of the first and second ferromagnetic layers, wherein the first ferromagnetic layer is formed before the second ferromagnetic layer is formed, and is located below the second ferromagnetic layer, angle of magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer relatively change due to an externally applied magnetic field, the spacer layer is configured with a nonmagnetic material of a hexagonal system, at least one of the first ferromagnetic layer and the second ferromagnetic layer is configured with a CoFe system magnetic alloy (CoFe and an alloy of CoFe as a main component) containing a component of Fe with at least 25% by atomic weight, the CoFe system magnetic alloy has a face centered cubic (fcc) structure and/or a hexagonal closed package (hcp) structure as a crystal structure at an interface with the spacer layer, and a total existing ratio of the fcc structure and the hcp structure in the CoFe system magnetic alloy at the interface with the spacer layer is 25% or more by an area ratio.