Dual spin valve magnetoresistive sensor

摘要

A magnetoresistive read sensor based on the spin valve effect and having a multilayered, dual spin valve structure is described. The sensor read element includes first, second and third layers of ferromagnetic material separated from each other by layers of non-magnetic metallic material. The first and third layers of ferromagnetic material, i.e., the outer layers of the structure, have their magnetization orientation fixed, while the second, intermediate ferromagnetic layer is magnetically soft and has its magnetization oriented perpendicular to that of both the outer ferromagnetic layers in the absence of an applied magnetic field. In one preferred embodiment, the two outer ferromagnetic layers have their magnetizations fixed parallel to each other by exchange coupling with adjacent antiferromagnetic layers.