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US 5,673,162 AGranted
Magnetoresistive head with soft adjacent layer comprising amorphous magnetic material
AssigneeAlps Electric Co., Ltd.
InventorMasamichi Saito
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AssigneeAlps Electric Co., Ltd.
InventorMasamichi Saito
Estimating the term…
A magnetoresistive head having a soft magnetic layer which comprises a Co--Fe--Ta amorphous magnetic material and applies a transverse bias magnetic field to a magnetoresistive layer. The amorphous magnetic material has such properties that the induced anisotropy is readily attained in the lateral direction, the rate of magnetoresistance change (.DELTA..rho./.rho.) is low, the magnetization stability in the lateral direction is enhanced, and Barkhausen noise is decreased. Since tantalum, one of the amorphous elements, sets the magnetostriction toward the minus side while iron (Fe) sets the magnetostriction toward the plus side, it is possible to control the magnetostriction of the soft adjacent layer by selecting the iron (Fe) concentration and to prevent the magnetoelastic effect from disturbing the magnetization stability in the lateral direction.
An anisotropic magnetoresistive head comprising:
Dependencies are inferred from the claim text.
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Disposition of magnetic thin films not used for directly coupling magnetic flux from the track to the MR film or for shielding: magnetic biasing films
Using magnetic thin film layers or their effects, the films being part of integrated structures: with intrinsic biasing, e.g. provided by…
Magnetoresistive: multilayer
Information storage based on relative movement between record carrier and transducer
Term ended 26 Mar 2016 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of the Invention
The present invention relates to a head which detects magnetism utilizing a magnetoresistance effect, and more particularly, the present invention relates to a magnetoresistive head of which a soft magnetic layer (hereinafter referred to as a SAL layer) has been improved so as to suppress Barkhausen noise.
2. Description of the Related Art
FIG. 1 is a ternary diagram showing the relation between the structure of the SAL and concentration of each element of a Co--Fe--Ta alloy used as a material thereof;
FIG. 2 is a graph showing the correlation between the induced anisotropic magnetic field, the coercive force, and the iron concentration of a Co--Fe--Ta alloy amorphous magnetic material of a SAL;
FIG. 3 is a graph showing the relation between the magnetostriction and the iron concentration of a Co--Fe--Ta alloy amorphous magnetic material of a SAL;
As described above, it is preferred that the SAL of a three-layer element of a magnetoresistive head be readily provided with an induced anisotropic magnetic field by, for example, film-forming in a magnetic field or by annealing in a magnetic field after film-forming. In addition, a small coercive force is another requirement for the SAL.
To satisfy those requirements, the SAL of the present invention comprises an amorphous material containing a magnetic element. An oriented regular arrangement of the magnetic atoms and an induced anisotropic magnetic field are thereby readily attained in the amorphous material. Further, when the content of the magnetic element increases, the induced anisotropic magnetic field can be applied more easily. A relatively high Curie temperature is required for the SAL, and for this purpose, cobalt (Co) is used as the magnetic element thereof. Moreover, in the present invention, the SAL contains iron (Fe) in addition to cobalt so as to apply the induced anisotropic magnetic field more readily by utilizing different kinds of magnetic elements. Consequently, in the above-described first aspect of the present invention, the SAL comprises cobalt (Co) and iron (Fe) as the magnetic element, and an amorphous element X.
In the second aspect, the above-mentioned amorphous element is at least one element selected from the group consisting of tantalum (Ta), niobium (Nb), yttrium (Y), nickel (Ni), boron (B), silicon (Si), titanium (Ti), vanadium (V), chromium (Cr), zirconium (Zr), molybdenum (Mo), hafnium (Hf), and tungsten (W).