Patent ID: 7286329

Claim:
A magnetic sensor comprising: an antiferromagnetic layer extending in a track-width direction; a ferromagnetic layer disposed over the antiferromagnetic layer, the ferromagnetic layer having a magnetization that remains substantially fixed in response to an applied magnetic field and extending in the track-width direction to terminate in a first end; a magnetically soft layer disposed over the ferromagnetic layer, the magnetically soft layer having a magnetization that rotates in response to the applied magnetic field, the magnetically soft layer extending in the track-width direction to terminate in a second end, the first and second ends forming part of a junction; a cap layer disposed over the magnetically soft layer such that the junction has a slope of less than forty-five degrees when measured at a location seven nanometers below a top of the cap layer; a magnetically hard layer disposed adjacent to at least the second end, the magnetically hard layer having a magnetization that remains substantially fixed in response to the applied magnetic field, to stabilize the magnetization of the end of the magnetically soft layer; and an underlayer disposed between the antiferromagnetic layer and the magnetically hard layer wherein the magnetic sensor has at least one set of characteristics selected from a group consisting of the following sets of characteristics: (a) an electrically conductive, nonmagnetic layer disposed between the ferromagnetic layer and the magnetically soft layer; (b) a first magnetically soft shield, and a first electrically insulating read gap layer adjoining the first magnetically soft shield and the antiferromagnetic layer, wherein the first electrically insulating read gap layer has a first uniform thickness; and (c) a second magnetically soft shield, and a second electrically insulating read gap layer adjoining the second magnetically soft shield and the antiferromagnetic layer, wherein the second electrically insulating read gap layer has a second uniform thickness of about fifty nanometers or less.