Patent ID: 7436638

Claim:
A magnetic sensor comprising: a plurality of sense layers, including a ferromagnetic pinned layer that has a magnetization that is stable in response to an applied magnetic field, a soft magnetic free layer that has a magnetization that rotates in response to the applied magnetic field, and a nonferromagnetic spacer layer that separates the pinned layer from the free layer, the free layer extending between two ends in a track-width direction; and a ferromagnetic pinning structure that has a first section extending a first distance in a stripe-height direction that is perpendicular to the track-width direction such that the first section is antiferromagnetically coupled to the pinned layer by a nonmagnetic metal layer, the pinning structure having a second section that is separated from the metal layer by the first section, the second section extending a second distance in the stripe-height direction, wherein the second distance is at least twice the first distance; and a ferromagnetic bias layer structure that is separated from the free layer by an electrically conductive nonmagnetic layer, the bias layer structure having a first part extending between two edges in the track-width direction such that the ends of the free layer are magnetically coupled to the edges of the first part, the bias layer structure having a second part that is separated from the electrically conductive, nonmagnetic layer by the first part, the second part extending at least twice as far as the first part in the track-width direction.