Patent ID: 6879472
Filing Date: 2005-04-12
Classification: B82Y,G01R,G11B,H01F,H01L,Y10S,Y10T

Abstract:
1. A magnetoresistive sensor comprising: an antiferromagnetic layer having a first region configured to create a non-aligned crystal lattice state and a second region configured to transform from a disordered lattice to an ordered lattice; and a pinned magnetic layer in contact with said first region of said antiferromagnetic layer such that an exchange coupling magnetic field is produced at an interface between said antiferromagnetic layer and said pinned magnetic layer to fix the magnetization of said pinned magnetic layer in a predetermined direction; wherein said antiferromagnetic layer comprises an antiferromagnetic material containing an element X and Mn, wherein said element X is selected from the group of elements consisting of Pt, Pd, Ir, Rh, Ru, and Os, and combinations thereof; wherein said antiferromagnetic layer is transformed by an annealing process to an annealed antiferromacinetic layer, wherein said annealed antiferromagnetic layer includes a region in which a ratio of an atomic percent of said element X to Mn increases in a direction towards said pinned magnetic layer; and wherein a crystalline structure of at least a portion of said annealed antiferromagnetic layer has a CuAu—I type face-centered square ordered lattice; a free magnetic layer; a non-magnetic intermediate layer between said pinned magnetic layer and said free magnetic layer; and a bias layer which aligns the direction of magnetization of said free magnetic layer in a direction intersecting the direction of magnetization of said pinned magnetic layer.