Patent ID: 8218270

Claim:
A magnetoresistive sensor structure comprising: a substrate; a magnetoresistive sensor on the substrate and comprising a stack of layers including a ferromagnetic free layer, the free layer having a front edge, a back edge recessed from the front edge, and two spaced-apart side edges; an electrically insulating layer on and in contact with the side edges of the free layer and on regions of the substrate adjacent the sensor; a seed layer consisting of material selected from Ir and Ru on and in contact with the insulating layer; a layer of ferromagnetic chemically-ordered FePt alloy on and in contact with the seed layer, the FePt alloy having a face-centered-tetragonal structure with its c-axis generally in the plane of the layer; and a capping layer comprising a Ru layer on and in contact with the FePt alloy layer.