Patent ID: 6201465
Filing Date: 2001-03-13
Classification: B82Y,G01R,G11B,Y10T

Abstract:
A magnetoresistive sensor comprising:a lower-gap layer having an upper surface;a first antiferromagnetic layer including first and second portions, each of the portions having an upper surface, wherein at least the upper surface of the first portion is separated along a first direction from the upper surface of the second portion, wherein at least the first and second portions are formed on the upper surface of the lower-gap layer;a nonmagnetic underlayer operatively disposed adjacent to the lower-gap layer and the first antiferromagnetic layer along said first direction, the nonmagnetic underlayer separating at least the upper surfaces of the first and second portions of first antiferromagnetic layer, wherein the nonmagnetic underlayer defines a track width having first and second offset lengths adjacent thereto, wherein the track width and the first and second offset lengths define a lead track width;a free magnetic layer including first and second sections closely adhered respectively to the upper surfaces of the first and second portions of the first antiferromagnetic layer, the free magnetic layer having a third section extending between the first and second sections, the third section formed on the nonmagnetic underlayer, wherein a direction of magnetization of the free magnetic layer is oriented through exchange anisotropic coupling with the first and second portions of the first antiferromagnetic layer;a nonmagnetic electrically conductive layer formed on the free magnetic layer,a pinned magnetic layer formed on the nonmagnetic electrically conductive layer; anda second antiferromagnetic layer formed on the pinned magnetic layer for pinning a direction of magnetization of the pinned magnetic layer through exchange anisotropic coupling such that the pinned direction of magnetization crosses the oriented direction of magnetization of the free magnetic layer,wherein the electrical resistance of the magnetoresistive sensor varies when the oriented direction of magnetization of the free magnetic layer is changed by an external magnetic field,wherein the free magnetic layer is interposed between the nonmagnetic electrically conductive layer and the first antiferromagnetic layer,wherein the nonmagnetic electrically conductive layer is interposed between the free magnetic layer and the pinned magnetic layer, andwherein the pinned magnetic layer is interposed between the nonmagnetic electrically conductive layer and the second antiferromagnetic layer.