Dual, synthetic spin valve sensor using current pinning
AssigneeRead-Rite Corporation
InventorsMatthew R. Gibbons, Marcos Lederman
Life of this patent
Estimating the term…
Abstract
A dual symmetric spin valve sensor consists of outer ferromagnetic pinned layers which are pinned by a current induced magnetic field. One of the outer pinned layers is magnetically coupled to an inner pinned layer which is pinned so that the magnetization of the other outer and the inner pinned layers are in the same direction. This provides the magnetization for the free layer disposed between the two layers to properly use the spin valve effect. The ferromagnetic layers are separated by conductor layers. The pin layers are synthetic antiferromagnetic layers consisting of the two layers tightly interlayer exchange coupled. The field induced by the sense current pins the pinned layers.
Claims21
A spin valve sensor comprising:
- a conductor for causing a current induced magnetic field;
- a first pinned layer capable of having the magnetization thereof pinned in a first direction by said current induced magnetic field;
- a second pinned layer capable of having the magnetization thereof pinned in a second direction by said current induced magnetic field;
- a third pinned layer capable of having the magnetization thereof pinned in said first direction by a magnetic coupling with said second pinned layer;
- and
- a free layer subject to the spin valve effect disposed between said first and third pinned layers.
A spin valve sensor comprising:
- first and second conductors capable of causing a current induced magnetic field;
- a first ferromagnetic layer capable of having the magnetization thereof pinned in a first direction by said current induced magnetic field;
- a second ferromagnetic layer capable of having the magnetization thereof pinned in a second direction by said current induced magnetic field;
- a third ferromagnetic layer capable of having the magnetization thereof pinned in said first direction by magnetic coupling with said second ferromagnetic layer;
- a ferromagnetic free layer subject to the spin valve effect disposed between said first and second conductors, said first and second conductors disposed between said first and third ferromagnetic layers.
A spin valve sensor comprising:
- first and second copper conductors capable of causing a current induced magnetic field;
- a first ferromagnetic layer of Co—Fe capable of having the magnetization thereof pinned in a first direction by said current induced magnetic field;
- a second ferromagnetic layer of Co—Fe capable of having the magnetization thereof pinned in a second direction by said current induced magnetic field;
- a third ferromagnetic layer of Co—Fe capable of having the magnetization thereof pinned in said first direction by magnetic coupling with said second ferromagnetic layer;
- a ferromagnetic free layer of NiFe and CoFe subject to the spin valve effect disposed between said first and second conductors, said first and second conductors disposed between said first and third ferromagnetic layers.
Dependencies are inferred from the claim text.