JPH05342535A - Magneto-resistance effect type head - Google Patents

Abstract

PURPOSE:To efficiently read a magnetic field generated from a medium and to enhance reproduction efficiency. CONSTITUTION:An MR element 1 with leading-out conductors 3, 3' joined to both ends is interposed between magnetic shielding bodies 4, 4' with a nonmagnetic insulating layer 2. The MR element 1 is inclined in the almost same direction as the inclination direction of a signal magnetic field generated from a recording medium. By this inclination of the MR element, a magnetic field received by an MR head can be increased and reproduction efficiency can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape device and a magnetoresistive reproducing head (hereinafter referred to as MR head) used for a magnetic disk or the like.

[0002]

2. Description of the Related Art A conventional MR head is disclosed in, for example, the document "Magnetic Head and Magnetic Recording", General Electronic Publishing Company, p. 182, the structure is as shown in FIG. 9A is a perspective view, and FIG. 9B is a sectional view taken along the line aa in FIG. In the figure, 1 is a magnetoresistive effect element (hereinafter referred to as MR element), 2 is a non-magnetic insulating layer, 3 and 3 '.
Is a lead conductor, 4 and 4'are magnetic shields, and 5 is a recording medium. The recording medium 5 moves in the arrow X direction. Two
The two lead conductors 3 and 3'are respectively joined to both ends of the MR element 1, and a sense current is passed through the lead conductors 3 and 3'to the MR element 1. The MR element 1 causes a resistance change by the magnetic field from the recording medium 5 and changes the voltage across the MR element 1. The MR head detects the signal magnetic field from the medium 5 based on this voltage change.

[0003]

When the relative permeability of the recording medium is assumed to be μ = 1, or the magnetic field lines of the magnetic field generated by the magnetic head in the free space are as shown in FIG. 6 (a). When the relative permeability of the recording medium is μ> 1, the lines of magnetic force are as shown in FIG.
It becomes like (b). That is, the magnetic field weakens in the medium due to the self-demagnetization effect. When the magnetic field as shown in FIG. 6B is repeatedly applied, if this repetition is fast, that is, when high density recording is performed, the magnetic field in the recording medium draws an ellipse as shown in FIG. At this time, the magnetic signal in the medium is
It is recorded at an angle θ with respect to the medium thickness direction. Also,
When the recording medium is a vapor-deposited tape, the easy axis of magnetization is inclined from the tape thickness direction in order to obtain the required performance.

As described above, the magnetization in the recording medium is generally inclined with respect to the thickness direction.

However, in the above-mentioned conventional MR head, only the vertical component of the magnetic field generated from the medium is read. Therefore, assuming that the magnitude of the signal magnetic field on the medium is H, the magnetic field component Hy that causes the magnetoresistive effect in the MR head is approximately H × co.
This is sθ, which is a cause of lowering the regeneration efficiency. Therefore, it has been a problem to read the signal magnetic field H to the maximum.

[0006]

In order to achieve the above object, an MR element is formed so as to be inclined at an angle θ with respect to the thickness direction of a recording medium. The tilt angle is made substantially equal to the magnetization direction of the recording medium.

[0007]

Since the MR element is formed so as to be inclined at the angle θ with respect to the thickness direction of the recording medium, the recording magnetic field of the medium can be efficiently read.

[0008]

1 is a diagram of a magnetoresistive head showing a first embodiment of the present invention. FIG. 1A is a perspective view,
(B) is sectional drawing in the aa line of (a) figure. In the figure, 1 is an MR element, 2 is a non-magnetic insulating layer, 3, 3
Reference numeral ′ is a lead conductor, 4 and 4 ′ are magnetic shields, and 5 is a recording medium. In this embodiment, the lead conductors 3,
The MR element 1 to which 3'is joined is provided between the magnetic shield bodies 4 and 4'through the non-magnetic insulating layer 2 as in the conventional example shown in FIG. The direction perpendicular to the plane and the MR element height direction form an angle θ. In this embodiment, the MR element 1 is NiFe.
The film and the nonmagnetic insulating layer 2 are formed of SiO ₂ or Al ₂ O ₃ film. Although the ME tape is used as the recording medium, the recording medium is not limited to this.

In FIG. 2, the inclination θ of the MR element is 10 ° and 20 °.
The reproduction efficiency is obtained when the output of θ = 0 is used as a reference at 30 °, 40 °, 50 °. The element has a film thickness of 20
nm, track width 5 μm, and device height 3 μm. The recording wavelength is 0.5 μm. At this time, the inclination of magnetization inside the tape was 20 to 30 when measured by the Bitter method.

By thus tilting the MR element at an angle of 15 ° to 45 °, the magnetic field received from the medium increases,
The reproduction efficiency is improved by 1.5 to 2 dB. This is explained as follows. Conventionally, the maximum difference between the angle of recording magnetization and the angle of the MR element is about 30 °, so that the magnetic field to be read becomes H × cos θ and the efficiency is lowered by about −1.25 dB. However, the angle difference was reduced by tilting the MR element at the angle θ. Further, by tilting the MR head, the film thickness of the non-magnetic insulating layer 2 set by the wavelength can be set thinner than the conventional one, so that the magnetic circuit flowing from the MR element to the magnetic shields 4 and 4'is shortened. Due to these factors, the regeneration efficiency was improved.

FIG. 3 is a diagram showing a second embodiment of the present invention and is a cross-sectional view of a composite type head of an inductive head and an MR head. In the figure, 1 is an MR element, 2 is a non-magnetic insulating layer, 5 is a recording medium, 6 is a substrate, 7 is a lower magnetic core, 7'is an upper magnetic core, 8 is a signal coil insulating layer, and 9 is.
Is a signal coil, and 10 is a gap. In this embodiment, the non-magnetic insulating layer 2 is formed on the substrate 6, the MR element 1 is formed, the non-magnetic insulating layer 2 is further formed, then the lower magnetic core 7 is formed, and the insulating layer 8 is formed. By laminating the signal coil 9 and the upper magnetic core 7 ', a composite head of an MR head and an inductive head is formed. After that, when the chip is processed, the MR element makes an angle .theta.
It was made to lean. In this embodiment, the substrate 6
Is Mn-Zn ferrite, magnetic cores 7 and 7'are Co-Z
r-Nb-Ta system amorphous, signal coil insulating layer 8
Is SiO ₂ , and the signal coil 9 is a laminated film of Cr—Cu—Cr. According to this embodiment, in addition to the same effect as in the first embodiment, the gap position between the recording head and the reproducing head can be formed close to each other, and the parallelism accuracy of the gap can be facilitated, so that the reproducing efficiency can be improved. improves. Furthermore, since the magnetic core of the recording head can be used as a magnetic shield, productivity is improved.

FIG. 4 is a diagram showing a third embodiment of the present invention and is a cross-sectional view of a composite type head of an oblique gap inductive head and an MR head. In the figure, the same parts as those in the second FIG. 3 are indicated by the same numbers. In this embodiment, in addition to the same effect as in the second embodiment, the gap portion of the inductive head is tilted at the same angle as the tilt of the MR element, so that the manufacturing method is easy.

FIG. 5 is a view showing a fourth embodiment of the present invention and is a cross-sectional view of a composite type head of an oblique gap inductive head and an MR head. Also in this embodiment,
The same effect as the third embodiment is obtained.

[0014]

According to the present invention, since the signal magnetic field from the recording medium can be efficiently read, it is possible to realize an MR head having high reproducing efficiency.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing the reproduction efficiency of the head of the first embodiment.

FIG. 3 is a diagram showing a second embodiment of the present invention.

FIG. 4 is a diagram showing a third embodiment of the present invention.

FIG. 5 is a diagram showing a fourth embodiment of the present invention.

FIG. 6 is a diagram showing lines of magnetic force of a magnetic field generated from a magnetic head.

FIG. 7 is a diagram showing a recording state of a magnetic signal in a recording medium.

FIG. 8 is a diagram showing a conventional magnetic effect head.

[Explanation of symbols]

1 ... Magnetoresistive effect element, 2 ... Non-magnetic insulating layer, 3, 3 '...
Lead conductors, 4, 4 '... Magnetic shield, 5 ... Recording medium, 6 ... Substrate, 7, 7' ... Magnetic core, 8 ... Signal coil insulating layer, 9 ... Signal coil, 10 ... Gap.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuo Abe, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Stock Video Media Research Laboratories, Hitachi, Ltd. Company electronic parts factory

Claims (5)

[Claims] 1. A magnetoresistive head comprising a magnetic layer (1) having a magnetoresistive effect, a non-magnetic insulating layer (2), a lead conductor (3), and a magnetic shield (4, 4 '). A magnetoresistive head (1), wherein the magnetoresistive element (1) is inclined with respect to the recording medium in the medium running direction. 2. The magnetoresistive effect head according to claim 1, wherein the angle of inclination of the magnetoresistive effect element (1) in the medium running direction is substantially equal to the inclination of magnetization of the recording medium. Mold head. 3. The magnetoresistive head according to claim 1, wherein the magnetoresistive element (1) has an inclination of ± 10 ° with respect to an inclination angle of 20 ° to 30 ° of the magnetization in the recording medium. A magnetoresistive head. 4. A magnetoresistive head comprising a magnetic layer (1) having a magnetoresistive effect, a nonmagnetic insulating layer (2), a lead conductor (3), and a magnetic shield (4, 4 '), and a magnet. In a composite head composed of a core (7, 7 '), a signal coil (9), and an inductive head composed of an insulating layer (8) joined together, the magnetoresistive effect element (1) runs on a recording medium. A composite head that is tilted in the direction. 5. The composite head according to claim 4, wherein the gap (10) of the inductive head is parallel to the magnetoresistive effect element (1).