US4816948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magneto-resistive head
Assignee: Hitachi Ltd
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Filing: 1987-02-10
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Granted: 1989-03-28
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Expires: 2007-02-10
Abstract
Abstract Magneto-resistive head comprising a magneto-resistive film, and a soft magnetic film disposed at one side of said magneto-resistive film, which soft magnetic film is magnetized by electric current flowing through the magneto-resistive film, to which a bias magnetic field is applied by the magnetization of the soft magnetic film, whereby they are so structured that 0.7×B SMR ×T MR <B SSF ×T SF is satisfied, where T MR and B SMR represent the thickness and the saturated magnetic flux density, respectively, of the magneto-resistive film and T SF and B SSF represent the thickness and the saturated magnetic flux density, respectively, of the soft magnetic film.
Inventors
- 👤 Yoshihisa Kamo
- 👤 Masahiro Kitada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:01
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/399; H; H10; H10N; H10N50/00; H10N50/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
137 words
A magneto-resistive head comprising; a magneto-resistive film, and a soft magnetic film disposed at one side of said magneto-resistive film, which soft magnetic film is magnetized by electric current flowing through said magneto-resistive film, to which a bias magnetic field is applied by the magnetization of said soft magnetic film, wherein the thickness, T MR , of said magneto-resistive film and the thickness, T SF , of said soft magnetic film satisfy 0.7×B.sub.SMR ×T.sub.MR <B.sub.SSF ×T.sub.SF, where B SMR represents the saturated magnetic flux density of the magneto-resistive film and B SSF represents the saturated magnetic flux density of the soft magnetic film, whereby said soft magnetic film is operated at an unsaturated level and magnetic flux passing through said soft magnetic film can be greater than magnetic flux passing through said magneto-resistive film at optimum bias.
Claim 2
Dependent Claim
137 words
A magneto-resistive head comprising; a magneto-resistive film, and a soft magnetic film disposed at one side of said magneto-resistive film, which soft magnetic film is magnetized by electric current flowing through said magneto-resistive film, to which a bias magnetic field is applied by the magnetization of said soft magnetic film, wherein the thickness, T MR , of said magneto-resistive film and the thickness, T SF , of said soft magnetic film satisfy 0.7×B.sub.SMR ×T.sub.MR <B.sub.SSF ×T.sub.SF, where B SMR represents the saturated magnetic flux density of the magneto-resistive film and B SSF represents the saturated magnetic flux density of the soft magnetic film, whereby said soft magnetic film is operated at an unsaturated level and magnetic flux passing through said soft magnetic film can be greater than magnetic flux passing through said magneto-resistive film at optimum bias.
Claim 3
Dependent Claim
47 words
A magneto-resistive head according to claim 1, further comprising a first shield film disposed at one side of said soft magnetic film and a second shield film disposed at another side of said magneto-resistive film opposite said one side at which said soft magnetic film is disposed.
Claim 4
Dependent Claim
40 words
A magneto-resistive head according to claim 2, wherein said first shield film is separated from said soft magnetic film by first insulating film, and said second shield film is separated from said magnetic magneto-resistive film by a second insulating film.
Claim 5
Dependent Claim
18 words
A magneto-resistive head according to claim 1, wherein said soft magnetic film is made of an amorphous material.
Claim 6
Dependent Claim
13 words
A magneto-resistive head according to claim 4, wherein said amorphous material is CoZrNb.
Claim 7
Dependent Claim
22 words
A magneto-resistive head according to claim 1, wherein said soft magnetic film and said magneto-resistive film are separated by an insulating film.
References Cited (Backward Citations)
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