JPH10334417A - Magnetic head device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a space occupied by an electrode by electrically connecting one-end parts of more than one magneto-resistance effect element to the same electrode and making the electrode common. SOLUTION: Reproducing magnetic heads 6 and 7 are formed integrally with plural magneto-resistance effect elements 9a and 9b, and a 1st electrode 8a, a 2nd electrode 8b and a 3rd electrode 8c are connected to these magneto- resistance effect elements 9a and 9b. The reproducing magnetic heads 6 and 7 are formed with the 1st electrode 8a so as to be connected with end parts of the magneto-resistance effect elements 9a and 9b, thus reducing the number of electrodes. Consequently, by forming the electrode 8a to connect with both of the magneto-resistance effect elements 9a and 9b in the reproducing magnetic heads 6 and 7, a spacing between the adjacent individual magneto-resistance effect elements 9a and 9b in the track widthwise direction C can be reduced, and hence track density of a recording medium can thus be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a magnetic head device having a magnetoresistive magnetic head for reproducing signals recorded on a tape-shaped recording medium having a plurality of tracks formed in parallel.

[0002]

2. Description of the Related Art In a conventional magnetic recording apparatus using a magnetic tape, there is a method in which a helical scan having a rotating head is used as in a video tape recorder (VTR), and tracking is performed according to a feeding speed of the magnetic tape. . Currently, an inductive head is used as a recording / reproducing head in a helical scan recording type VTR. The track width of the magnetic recording medium in the helical scan method has a lower limit due to an error in a reproduction signal output and a rotating head mechanism, and is about 5 μm.

On the other hand, generally, a QIC (Quarter Inch cartr
idge) A fixed head is used, such as a 1/4 inch cassette data streamer, which is called a data cartridge and is used as a computer data streamer, or a digital compact cassette (DCC) for audio. There is a fixed head multi-track recording method in which a plurality of tracks are arranged in parallel in the length direction of the magnetic tape at a track density at which track deviation does not become a problem even if the track direction varies in the track direction. Currently, the lower limit of the track pitch of the magnetic tape in the fixed head multi-track recording method is about several tens μm due to the positioning accuracy of the magnetic tape and the magnetic head.

[0004] In the field of hard disks, high output is expected from inductive heads as the disks become smaller and the recording density is improved. Also,
In the field of hard disks, by using a hard disk having a small disk diameter, a magnetoresistive element using a magnetoresistive effect element (hereinafter referred to as an MR element) that does not decrease the reproduction output even when the relative speed with respect to the magnetic head decreases. Attention has been paid to an effect type magnetic head (hereinafter, referred to as an MR head).

[0005] Further, the MR disk applied to a tape-shaped recording medium has been put to practical use as a reproducing magnetic head for reproducing signals recorded on the above-mentioned QIC data cartridge or DCC.

[0006]

As described above, the QIC
And a conventional multi-track magnetic head used as a reproducing magnetic head for reproducing a signal recorded on a DCC, the track density of a recording medium is several tens μm to several hundred μm.
Since there is a margin in the track density to be recorded on the recording medium, there is provided an MR element corresponding to each track formed on the recording medium and an extraction electrode for detecting a resistance change of the MR element.

However, in the above-described MR head, it is necessary to reduce the distance between adjacent MR elements in order to increase the track density of a recording medium on which a signal is recorded to increase the recording signal density.

Here, in the MR head, it is necessary to supply a sense current of about 10 mA as an operating current. Therefore, it is necessary to reduce the electrical resistance of the electrode portion in order to reduce heat generation at the extraction electrode connected to each MR element. As a means for reducing the electrical resistance of the extraction electrode as described above, it is possible to increase the area of each extraction electrode. However, this M
In the R head, it is necessary to connect a lead electrode for each MR element, and the space occupied by the lead electrodes increases. As described above, when the space occupied by the extraction electrode becomes large, it is impossible to increase the density of the magneto-sensitive portion in the track width direction of the MR head, and it becomes difficult to improve the track density recorded on the recording medium. .

Therefore, the present invention has been proposed in view of the above-mentioned circumstances, and can reproduce a magnetic signal recorded on a recording medium in response to the increase in track density of the recording medium. It is an object of the present invention to provide a magnetic head device provided with a magnetoresistive magnetic head.

[0010]

A magnetic head device according to the present invention which solves the above-mentioned problems has a plurality of magnetoresistive effects which are arranged facing a sliding surface of a recording medium and detect a magnetic signal recorded on the recording medium. An element is provided, and one end of at least two or more magnetoresistive elements is electrically connected to the same electrode, and the electrode is a common electrode, so that the space occupied by the electrode can be reduced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a magnetic head device according to the present invention will be described with reference to the drawings. The present invention is not limited to the following examples, and it goes without saying that the configuration and the like can be arbitrarily changed without departing from the gist of the present invention.

As shown in FIG. 1, a magnetic head 1 provided in the magnetic head device is a magnetic head having four channels, and includes a recording magnetic head chip 2 and one side of the recording magnetic head chip 2. First reproducing magnetic head chip 3 and recording magnetic head chip 2
And a second reproducing magnetic head chip 4 joined to the other side.

The recording magnetic head chip 2 has four recording magnetic heads 5 integrally formed on a substrate by a thin film process. Here, the recording magnetic head 5 is an inductive type magnetic head that writes a signal on a recording medium using electromagnetic induction, and includes a magnetic core having a magnetic gap and a winding coil wound around the magnetic core. Have.

On the other hand, in the first reproducing magnetic head chip 3, four reproducing magnetic heads 6 are integrally formed on a substrate by a thin film process, and similarly, in the second reproducing magnetic head chip 4, Also, four reproducing magnetic heads 7 are integrally formed on a substrate by a thin film process. Here, the reproducing magnetic heads 6 and 7 are MR heads for detecting a signal from a recording medium using a magnetoresistive effect, and include a magnetoresistive element and two magnetoresistive elements at both ends in the track width direction. And a pair of connected electrodes.

In the magnetic head 1, when data is recorded on the recording medium, the data is recorded on the recording medium by the recording magnetic head 5 at the same time that the recorded data is reproduced. The data reproduced and recorded by the magnetic head 6 or the reproducing magnetic head 7 is verified.

That is, when the recording medium is slid with respect to the magnetic head 1 in the direction shown by the arrow A for recording, the recording is performed by the recording magnetic head 5 and immediately after the recording, the recorded data is read. The data reproduced and recorded by the reproducing magnetic head 6 is verified. When recording is performed by sliding the recording medium with respect to the magnetic head 1 in the direction indicated by the arrow B, the recording is performed by the recording magnetic head 5 and immediately after the recording, the recorded data is read by the reproducing magnetic head. The data reproduced by the head 7 and recorded is verified.

In the reproducing magnetic heads 6, 7, for example, NiZn ferrite is used as a substrate, a silicon oxide film is formed on the substrate, and a magnetoresistive layer is formed on the silicon oxide film. In the reproducing magnetic heads 6, 7, an underlayer made of, for example, Ti is formed on the magnetoresistance effect layer, and an electrode made of, for example, Cu is formed on the underlayer.

Further, the reproducing magnetic heads 6 and 7 are manufactured by forming a silicon oxide film on an electrode and bonding NiZn ferrite which functions as a magnetic shield of a magnetoresistive layer on the silicon oxide film. doing.

Here, the silicon oxide film is formed to a thickness of about 500 nm using an RF magnetron sputtering device. The magnetoresistive layer has a composition of, for example, Fe
₁₅ Ni ₈₀ Ta magnetic thin film made ₅ formed to a thickness of about 35 nm, is formed with a thickness of about 15nm to Ta, composition at a thickness of about 30nm magnetic thin film composed of Fe ₂₀ Ni ₈₀ By forming, a laminated film having a soft adjustable layer (hereinafter, referred to as SAL) bias structure is formed. The sputtering conditions for forming the silicon oxide film and the magnetoresistive layer were as follows: argon was used as a sputtering gas, the gas pressure was about 0.3 Pa, and the deposition rate was about 0.1 to 0.5 nm / sec. Is formed. The electrode is formed by forming Ti as a base film on the magnetoresistive layer with a thickness of about 200 nm,
Is formed to a thickness of about 3 μm, and is formed into a predetermined pattern by photolithography.

In the reproducing magnetic heads 6 and 7, Barkhausen noise of the magnetoresistive layer is reduced, and an antiferromagnetic material such as FeMn or NiMn is provided between the magnetoresistive layer and the electrode. It may be formed with a thickness of about 5 nm to about 100 nm.

As the magnetic shield of the magnetoresistive layer, not only the above-mentioned NiZn ferrite but also a magnetic material may be formed on a non-magnetic substrate to magnetically shield the magnetoresistive layer. . As the non-magnetic substrate, for example, altic, crystallized glass, non-magnetic ferrite, or the like can be used. As a magnetic material to be formed on the non-magnetic substrate, for example, Sendust (Fe-Al-
Si alloy), a Co-based amorphous alloy, Permalloy, or the like can be used.

As described above, the reproducing magnetic heads 6 and 7 constituting the magnetic head 1 have the electrodes 8 for supplying a sense current to the magnetoresistive element as shown in FIG.
Are patterned so as to be connected to both electrodes 8 of the adjacent magnetoresistive element 9. That is, the reproducing magnetic heads 6 and 7 include the first magnetoresistive effect element 9.
a and a first electrode 8a connected to both ends of the second magnetoresistive element 9b is formed as a common electrode. A second electrode 8b is formed on the first magnetoresistive element 9a, and a third electrode 8b is formed on the second magnetoresistive element 9b.
Electrode 8c is formed. That is, in the reproducing magnetic heads 6 and 7, the plurality of magnetoresistive elements 9 are integrally formed, and the first electrode 9a, the second electrode 9b, and the third Electrode 9c is connected.

In the reproducing magnetic heads 6, 7, the number of electrodes can be reduced by forming the first electrodes 8a so as to be connected to the ends of the magnetoresistive elements 9a and 9b. it can. Therefore, in the reproducing magnetic heads 6, 7, the electrodes 8a are formed so as to be connected to both the magnetoresistive elements 9a, 9b, so that the track width direction between the adjacent magnetoresistive elements 9a, 9b can be improved. C
Can be reduced. Therefore, the reproducing magnetic heads 6 and 7 can cope with an increase in the track density of the recording medium.

Further, the reproducing magnetic heads 6, 7
By using the first electrode 8a that shares the electrodes of the adjacent magnetoresistive elements 9a and 9b, the distance between the magnetoresistive elements 9a and 9b can be reduced.
The area of each of the electrodes 8a, 8b, 8c can be increased. Therefore, in the reproducing magnetic heads 6 and 7, the resistance value of the electrodes can be reduced, and the heat generated by supplying a current can be reduced.

On the other hand, in the conventional reproducing magnetic head 10, as shown in FIG. 3, electrodes 8 are formed at both ends of each magnetoresistive element 9. When the electrodes 8 are formed at both ends of each magnetoresistive element 9 by setting the length t ₁ of each electrode 8 in the track width direction C to about 50 μm, the reproducing magnetic head 10 t ₂ becomes as large as about 120 μm. Thus, when the magnetoresistive element becomes the interval t ₂ of 9 large, it becomes impossible to narrow only up to about 120μ about the track pitch for recording the above-described recording medium. In contrast, in the reproducing magnetic head 6 and 7 described above, the magnetoresistive element 9a, can be about 60μm approximately the distance t ₂ between 9b.

As shown in FIG. 4, electrodes 8d and 8e of the reproducing magnetic heads 6 and 7 are connected to both ends of the magnetoresistive elements 9c and 9d in the depth direction D. At this time, the fourth electrode 8d disposed on the medium sliding surface side is disposed so as to be connected to the magnetoresistive elements 9c and 9d.
That is, in the reproducing magnetic heads 6 and 7, the fourth electrode 8d connected to the plurality of magnetoresistive elements 9c and 9d is arranged as a common electrode on the medium sliding surface side, and the fifth electrode 8e is individually connected. Electrodes are arranged at the other ends of the magnetoresistive elements 9c and 9d.

As described above, the reproducing magnetic heads 6, 7 provided with the fourth electrode 8d and the fifth electrode 8e are provided with the respective electrodes 8d.
The length t ₁ of the d and 8e in the track width direction C is set to about 50.
When the thickness is set to μm, the distance t ₂ between the magnetoresistive elements 9c and 9d can be set to about 60 μm.

In the reproducing magnetic heads 6 and 7 described above, the fourth electrode 8d disposed on the medium sliding surface side is used as a magnetic shield for the magnetoresistive elements 9c and 9d in order to simplify the manufacturing process. This magnetic material may be used as an electrode by being connected to a functional magnetic material.

The reproducing magnetic heads 6 and 7 are made of an FeNi alloy having a thickness of about 10 nm instead of a laminated film having a softly-adjustable layer (SAL) bias structure.
And a thickness of about 3.5 n on the first magnetic film.
about 10 nm thick as a second magnetic film, and about 10 nm thick Fe on the second magnetic film about 10 nm thick.
A so-called spin-valve type giant magnetoresistance effect film in which an Mn alloy is laminated may be used.

The first magnetic film is not limited to the above example, but may be made of a FeNiCo alloy, NiCo, CoFe
Alloys may be used. Further, as the conductive film, Ag,
Au, Cr, Rh and alloys thereof can be used. Further, as the second magnetic film, a NiFe alloy, FeNiC
o, CoFe alloys can be used. As the antiferromagnetic film, NiMn, NiMnCr, NiMnRu, F
eMnCr, FeMnRu, CoO, NiCoO, Rh
Mn, RuMn, IrMn alloy and the like can be used.

As described above, when the spin-valve type giant magnetoresistive film is used instead of the laminated film having the soft adjustable layer (SAL) bias structure, the reproducing magnetic heads 6 and 7 have the same structure. When the length in the track width direction A is about 50 μm,
The reproduction output can be approximately doubled as compared with the case where the laminated film having the adjustable layer (SAL) bias structure is used.

In addition, the reproducing magnetic heads 6 and 7 are each made of 15 nm thick Cu and about 1 nm thick FeNiCo alloy instead of Fe ₂₀ Ni ₈₀ constituting the magnetoresistive layer. A so-called giant magnetoresistive film having an artificial lattice structure that is periodically laminated may be used. Further, the reproducing magnetic heads 6 and 7 use NFe instead of the above-mentioned FeNiCo alloy.
An iCo or CoFe alloy may be used, and instead of Cu, Ag, Au, Cr, Rh or a giant magnetoresistive film having an artificial lattice structure using these alloys may be used.

As described above, Fe ₂₀ N having a thickness of about 30 nm
Instead of i _80, by using a giant magnetoresistive effect film having an artificial lattice structure as described above, approximately 50μm the length in the track width direction A of the magnetoresistive head
In this case, the reproducing output can be approximately doubled as compared with the reproducing magnetic head using Fe ₂₀ Ni ₈₀ .

In the reproducing magnetic head described above, since the electrodes connected to the adjacent magnetoresistive elements are shared, crosstalk between the tracks may occur. The crosstalk can be prevented by adjusting the distance between the arranged magnetic shields. That is, in the reproducing magnetic head, the distance between the magnetic shields in the portion where the electrodes are disposed is made smaller than the distance in the portion where the magnetoresistive element is disposed, so that the crossing between the reproducing magnetic heads is reduced. Talk can be reduced.

The above-described magnetic head device has a magnetic head provided with a lateral magnetoresistive effect type magnetoresistive effect head in which a magnetoresistive effect element is arranged so that a reproducing current flows in a track width direction with respect to a recording medium. Although an example applied to the device has been described, the present invention can also be applied to a magnetic head device including a vertical type magnetoresistive effect type magnetic head in which a magnetoresistive element is disposed so as to allow a reproduction current to flow in a direction perpendicular to a recording medium. is there.

[0036]

As described above in detail, in the magnetoresistive head according to the present invention, one end of at least two or more magnetoresistive elements is electrically connected to the same electrode, and the electrodes are commonly used. Since the electrodes are used, the number of electrodes can be reduced, and the space occupied by the electrode lead portions can be reduced. Therefore, in the magnetoresistive head, the track width can be reduced in accordance with the improvement of the track density of the recording medium.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a magnetic head provided in a magnetic head device to which the present invention is applied.

FIG. 2 is a main part top view showing an example of a reproducing magnetic head.

FIG. 3 is a main part top view showing a conventional reproducing magnetic head.

FIG. 4 is a main part top view showing another example of the reproducing magnetic head.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 magnetic head, 4 reproducing magnetic head chip, 6 reproducing magnetic head, 7 reproducing magnetic head, 8 electrodes, 9
Magnetoresistance effect element

Claims (5)

[Claims] A plurality of magnetoresistive elements arranged to face a recording medium sliding surface for detecting a magnetic signal recorded on the recording medium, wherein one end of at least two or more magnetoresistive elements has the same end; A magnetic head device electrically connected to an electrode, wherein the electrode is a common electrode. 2. The magnetic head device according to claim 1, wherein said plurality of magnetoresistive elements are formed integrally. 3. The common electrode is connected to an end of each magnetoresistive element on the side of the recording medium sliding surface, and an individual electrode is connected to an end on the opposite side of each magnetoresistive element. The magnetic head device according to claim 1, wherein: 4. The magnetic head according to claim 1, wherein the magnetoresistive element has two or more magnetic layers and exhibits a magnetoresistive effect depending on the angle of the magnetization direction between the magnetic layers. apparatus. 5. A magnetic shield is provided on both sides of the magnetoresistive element in the track direction, and a distance between the magnetic shields is larger on both sides of each magnetoresistive element than a portion where the magnetoresistive elements are not arranged. 2. The magnetic head device according to claim 1, wherein: