JPH07129929A - Magneto-resistance effect type magnetic head - Google Patents

Abstract

PURPOSE:To make it hard to fetch unnecessary magnetic field in a sliding direction or a tracking direction, to drastically improve SN ratio at the time of reproducing, and to cope with making the rotating speed of a medium high, making a signal a short bit, and making the density of a track high by realizing thinning in the length of a reproducing gap and narrowing the track. CONSTITUTION:In an MR head where an MR element 4 is arranged so that its longitudinal direction may be perpendicular to an ABS surface 1; distances L1 and L2 between the MR element 4 and thin film magnetic cores 7 and 8 arranged above and below the element 4 in the same direction as a direction X passing on the medium are set to <=0.3mum and the width of the MR element 4 in a direction perpendicular to the direction passing on the medium is set to <=4mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive magnetic head suitable for reading recorded information written on a hard disk, for example.

[0002]

2. Description of the Related Art With the recent demand for miniaturization and large capacity of hard disks, a magnetoresistive effect magnetic head (hereinafter referred to as MR head), which can easily achieve higher linear recording density (higher TPI), is attracting attention. Has been done. However, since the MR head is a read-only head, a winding type thin film magnetic head (hereinafter referred to as an inductive head) which is a recording head is required as a magnetic head for a hard disk.

The MR head and the inductive head are usually laminated and formed on a substrate called a slider.
Combined and integrated. That is, Al ₂ as shown in FIG.
The substrate 101 made of an O ₃ —Ti—C-based sintered body has a structure shown in FIG.
As shown in 3, the head material is laminated using a thin film process such as sputtering, plating, photolithography,
A plurality of head elements (composite head of MR head and inductive head) 102 are manufactured. Then, as shown in FIG. 14, the slider 103 is manufactured by cutting out each head chip and performing a process for determining an outer dimension. Thereafter, as shown in FIG. 15, the lead wire 104 is soldered to the head terminal electrode and the slider 103 is attached to the suspension mechanism 105 to complete the process.

As shown in FIGS. 16 to 18, the composite magnetic head composed of the MR head and the inductive head has a magnetoresistive effect element (hereinafter referred to as MR element) 106 as a pair of thin film magnetic cores 107 and 108. One thin film magnetic core 108 and this thin film magnetic core 1 are placed on a so-called shield type MR head sandwiched by
An inductive head that forms a closed magnetic circuit with the thin-film magnetic core 110 that is laminated on the 08 via the head winding 109 is laminated on the same slider 103.

That is, in this composite magnetic head, M
A pair of thin film magnetic cores 107, 1 sandwiching the R element 106
08 selectively selects the magnetic field from the medium during reproduction.
It functions as a magnetic shield core for drawing into 06,
A thin film magnetic core 110 sandwiching the head winding 109 and the thin film magnetic core 108 on one side has a function as an induction magnetic core at the time of recording, that is, two gaps having a recording gap g ₁ and a reproducing gap g ₂ separately. It has a type head configuration.

[0006]

The reproducing gap length of the MR head is represented by the facing distance in the linear recording direction between the MR element 106 and the thin film magnetic cores 107 and 108 provided above and below it. In the case of such a head, the distance between the lower layer thin film magnetic core 107 and the MR element 106 is the lower layer reproduction gap length, and the upper layer thin film magnetic core 108.
The distance between the MR element 106 and the MR element 106 becomes the reproduction gap length of the upper layer.

When the reproduction gap length is long, as shown in FIG. 19A, a large amount of magnetic flux from the medium 111 is drawn in, so that there is an advantage that a large output can be obtained at the time of signal detection. However, on the other hand, since it is easy to pick up even unnecessary magnetic flux, the SN ratio decreases. Further, if the relative speed between the medium 111 and the head is increased to increase the density and transfer rate, the MR element 106 easily takes in an unnecessary magnetic field in the rotating direction, which also causes a decrease in the SN ratio. .

On the other hand, when the reproduction gap length is short, only the magnetic flux in the vicinity of the gap is drawn in as shown in FIG. 19B, so that the information recorded at high density can be read, and Even if the relative speed between the medium 111 and the head is increased, an unnecessary magnetic field is not taken in, and S
No decrease in N ratio occurs.

However, if the reproducing gap length is made too short, the distance between the MR element 106 and the thin film magnetic cores 107, 108 becomes too short, which may cause a short circuit. For this reason, until now, in order to secure the reliability of the magnetic and electrical insulating properties, the reproduction gap length had to be made longer than 0.3 μm. That is, if the insulating film (gap film) provided between the MR element 106 and the thin film magnetic cores 107 and 108 is simply formed on the thin film magnetic core 107, the insulating film is hit in the subsequent etching process or the like, so that the reliability is improved. Is impaired, and there is a limit to thinning the film thickness.

On the other hand, the reproducing track width of the MR head is determined by the width W of the MR element 106 in the direction perpendicular to the direction of passage on the medium, as shown in FIG. This MR element 106
If the width W of the recording medium is wide,
At the time of reproduction, adjacent track information other than the corresponding track is also reproduced as noise, resulting in a reduction in the SN ratio of the reproduction output.

On the other hand, if the width W of the MR element 106 is narrowed, the above problem is solved, but the magnetic anisotropy becomes unstable, and Barkhausen noise is generated due to the movement of the domain wall, and the reproduction output is unsatisfactory. Be stable. In order to stabilize the magnetic anisotropy of the MR element 106, an external magnetic field may be applied in the track width direction at the time of depositing Ni—Fe to form a film, but the effect is obtained. The width W of the MR element 106 must be 5 μm or more. In other words, this will hinder the narrowing of the reproduction track.

Therefore, the present invention has been proposed in view of the above-mentioned technical problems of the related art, and by making the reproducing gap length thin and narrowing the track, the sliding direction and the track direction are unnecessary. It is difficult to capture the magnetic field and S during playback
It is an object of the present invention to provide a magnetoresistive effect magnetic head capable of significantly improving the N ratio and capable of coping with higher medium rotation, shorter signal bit length, and higher track density.

[0013]

In order to achieve the above-mentioned object, according to the present invention, one end edge faces a contact surface with a magnetic recording medium, and its longitudinal direction is perpendicular to the contact surface. A magnetoresistive effect element arranged so as to face the contact surface of the magnetic recording medium, and a tip electrode laminated on the tip side of the magnetoresistive element, and laminated on the rear end side of the magnetoresistive element. A rear end electrode, a bias conductor for applying a bias magnetic field to the magnetoresistive effect element via an insulating layer on the magnetoresistive effect element, and a magnetoresistive effect element in which the front end electrode and the rear end electrode are laminated, A pair of thin film magnetic cores sandwiching a bias conductor are provided, and a gap between the magnetoresistive effect element in the same direction as the direction of passing on the medium and the thin film magnetic cores arranged above and below is 0.3 μm or less. , And the direction of passing over the medium Width of the vertical direction of the magnetoresistive element is characterized in that it is 4μm or less.

With the conventional technology, the reproduction gap length could not be reduced to 0.3 μm or less, but with the improvement of the process technology, the reproduction gap length can be reduced to 0.3 μm or less. For example, an insulating film that secures electrical / magnetic insulation is formed on the thin film magnetic core excluding the depth portion of the reproducing gap, and the gap film is formed thereon. Alternatively, a groove is provided in the thin film magnetic core except the depth portion of the reproduction gap, an insulating film that secures electrical / magnetic insulation is formed in the groove, and the gap film is formed thereon. By doing this, the reproduction gap length is 0.3 μm or less up to the depth,
In the other parts, the insulating layer ensures the insulation between the MR element and the thin film magnetic core.

On the other hand, in order to stabilize the magnetic anisotropy even when the width of the MR element is 4 μm or less, the edge of the MR element is sharpened or applied when the MR element is formed by vapor deposition. There are methods such as strengthening the magnetic field.

[0016]

In the present invention, the distance between the MR element and the thin film magnetic cores arranged above and below the MR element, that is, the reproducing gap length is 0.3 μm or less, and the width of the MR element as the track width is 4 μm or less. It becomes difficult to take in an unnecessary magnetic field in the sliding direction and the track direction, and the SN ratio at the time of reproduction is improved. Therefore, it is possible to cope with the high rotation of the medium, the short bit of the signal, and the high track density.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments to which the present invention is applied will be described in detail below with reference to the drawings. In this example,
This is an example of a two-gap type composite magnetic head in which an MR head and an inductive head are laminated and formed on the same slider, and a reproducing gap and a recording gap are separately provided.

As shown in FIGS. 1 to 3, the composite type magnetic head is an MR head in which a reproducing magnetic gap g ₁ is exposed on an ABS surface (air bearing surface) 1 which is a contact surface with a hard disk. And an inductive head for exposing the recording magnetic gap g ₂ on the ABS 1 is laminated on one side surface of the slider 2 made of an Al ₂ O ₃ —TiC substrate or the like to form a so-called 3-pole type head configuration. There is.

As shown in FIG. 3, the MR head has a pair of electrodes 3a and 3b (hereinafter referred to as ABS) for passing a sense current from a constant current source (not shown) to the front end and the rear end, respectively.
The electrode 3a provided on the surface 1 side is referred to as a front end electrode 3a, and the electrode 3b provided on the rear end side is referred to as a rear end electrode 3b. ) Are laminated, and a bias conductor 5 which gives the MR element 4 a magnetic field state in a desired direction.

The MR element 4 has the longitudinal direction of the ABS element.
It is provided so as to be perpendicular to the surface 1, and one edge thereof faces the ABS surface 1. Further, the MR element 4 has a laminated film structure in which a pair of MR thin films that are magnetostatically coupled via a non-magnetic insulating layer made of, for example, SiO ₂ is laminated, and Barkhausen noise is prevented from occurring. It is like this. The MR thin film is
For example, it is made of a ferromagnetic thin film such as permalloy and has a film thickness of about several hundred angstroms.

One end of the tip electrode 3a has an ABS surface 1
Is laminated on the front end portion of the MR element 4 so as to face the above. The tip electrode 3a has a function as an electrode for supplying a sense current to the MR element 4 by passing a current between it and a rear electrode 3b which will be described later, and also as an upper layer gap film for the reproducing magnetic gap g _1. It is supposed to do.

On the other hand, the rear end electrode 3b is provided directly on the rear end portion of the MR element 4 so as to extend to the back side.
The R element 4 is electrically connected.

The bias conductor 5 is provided on the insulating layer 6 provided on the MR element 4 in a direction substantially perpendicular to the MR element 4 (direction perpendicular to the plane of FIG. 1), that is, M.
It is provided so as to cross the R element 4. A bias current from a DC power supply is applied to both ends of the bias conductor 5. Therefore, the direct currents supplied from the both terminal portions flow in the track width direction, and the resulting bias magnetic field is applied in the longitudinal direction of the MR element 4.

In this MR head, the MR element 4 is connected to the permalloy (Ni--F) via the insulating layer 6.
The so-called shield type structure is sandwiched between the first thin film magnetic core 7 and the second thin film magnetic core 8 made of a magnetic material such as e).

The first thin film magnetic core 7 provided on the lower side of the MR element 4 is perpendicular to the ABS surface 1 so that one end of the first thin film magnetic core 7 faces the ABS surface 1 on the slider 2. It is provided so as to extend to. An insulating film 14 that functions as a lower gap film of the reproducing magnetic gap g ₁ is provided between the first thin film magnetic core 7 and the MR element 4.

On the other hand, the other second thin film magnetic core 8 provided so as to be opposed to the second thin film magnetic core 8 has one end thereof facing the ABS 1 like the first thin film magnetic core 7.
A reproducing magnetic gap g ₁ is formed at the tip portion thereof, and is provided so as to extend perpendicularly to the ABS surface 1 toward the back side.

On the other hand, the inductive head is the MR
The second thin film magnetic core 8 functioning as the shield core of the element 4 is used as one thin film magnetic core, and the ABS surface is formed by the third thin film magnetic core 9 which is laminated facing the second thin film magnetic core 8. The recording magnetic gap g ₂ is formed between the front ends of the recording magnetic gap g.

That is, the third thin film magnetic core 9 laminated so as to face the second thin film magnetic core 8 has the ABS surface 1
The recording magnetic gap g ₂ is formed at the opposite end where the gap is narrowed by being bent toward the side of the second thin film magnetic core 8 at the front end portion facing to. In addition, this third
The thin film magnetic core 9 is magnetically contacted with the second thin film magnetic core 8 at the rear end.

Then, the third thin film magnetic core 9 and the second thin film magnetic core 9
In the magnetic coupling portion 10 which is the connection portion of the thin film magnetic core 8, the spiral head winding 11 is provided so as to surround the magnetic coupling portion 10. The head winding 11 includes a third thin film magnetic core 9 and a second thin film magnetic core 8.
An insulating layer 12 is embedded in order to secure insulation between them.

A protective layer 13 for protecting the MR head and the inductive head laminated on the slider 2 is formed on the third thin film magnetic core 9.

In particular, in this embodiment, the distance L ₁ between the MR element 4 in the same direction as the direction of passing on the medium indicated by the arrow X in FIG. 3 and the thin film magnetic cores 7 and 8 arranged above and below the MR element 4 is shown. ，
L ₂ (hereinafter, referred to as reproduction gap lengths L ₁ and L ₂ ) are both 0.3 μm or less. That is, MR
The facing distance L ₁ between the element 4 and the first thin-film magnetic core 7 (corresponding to the thickness of the insulating film 14) is 0.3 μm, and the MR element 4
And the second thin film magnetic core 8 facing each other L ₂ (tip electrode 3
It corresponds to the thickness of a. ) Is 0.3 μm or less.

The reason why the reproduction gap lengths L ₁ and L ₂ are set to 0.3 μm or less is based on the following. For example, recording density 2
If the track density is set to 4000 TPI in order to achieve 00 Mb / inch ² or more, the linear recording density is (200
Mb / inch ² ÷ 4000 TPI) 50KFCI or more is required. Therefore, D ₇₀ (the number of magnetization reversals per inch at the time when the output drops to 70% when the recording frequency is increased) is 50 KFCI or more when the gap length is 0.3 μm or less. . In practice, the linear recording density that can be used in a hard disk drive device is 200 Mb / inch ² when the head output is about 70% to 100%.
In order to achieve the above at 4000 TPI, the gap length must be 0.3 μm or less.

Further, in this magnetic head, as shown in FIG. 2, the width W of the MR element 4 in the direction Y perpendicular to the direction X on the medium is 4 μm or less. That is, the track width of the reproducing magnetic gaps g ₁ and g ₂ is 4 μm or less. For example, when the track density is 4000 TPI or more, the effective track width must be 4 μm or less. Here, the effective track width includes the MR element 4
The width W must be taken into consideration for fringing. That is, the effective track width ≧ the width of the MR element. Therefore, in order to obtain the track density of 4000 TPI or more, 4 ≧ effective track width, so that 4 ≦ MR
It is the width of the element.

As described above, the reproduction gap lengths L ₁ and L ₂
Is 0.3 μm or less and the width W (track width) of the MR element 4 is 4 μm or less so that the SN ratio at the time of reproduction is improved, the rotation speed of the medium is increased, and the signal is reproduced. It is possible to cope with shorter bit length and higher track density, and it is possible to achieve higher recording density and higher transfer rate of the hard disk drive device.

Next, a method for manufacturing the above-mentioned composite magnetic head will be described in the order of the steps. First, FIG.
As shown in (a) and (b), a first-layer shield magnetic body made of, for example, an Fe—Si—Al magnetic material is formed on the slider 15 made of an Al ₂ O ₃ —TiC substrate or the like by sputtering or the like. A first thin film magnetic core 16 is formed. The first thin film magnetic core 16 is formed as a pattern in which the front portion where the reproducing magnetic gap is formed is narrow and the core width is wide across the back side.

Next, as shown in FIGS. 5 (a) and 5 (b),
On the first thin film magnetic core 16, for example, Al₂O₃Etc.
The edge material is sputtered or the like to a predetermined film thickness (0.3
(less than or equal to μm), for example, form a film with a thickness of about 0.4 μm
As a result, the lower gap film 17 is formed. In addition, in FIG.
The lower gap film 17 is not shown. After that,
The lower gap film 17 is smoothed and the lower gap thickness is
Then Al ₂O₃Cloth for mirror polishing to control the thickness
Polishing is performed to reduce the thickness of the lower gap film 17 to 0.3.
For example, it is 0.2 μm or less.

Next, as shown in FIGS. 6 (a) and 6 (b),
Ni-Fe of 40 nm and A on the lower gap film 17 are sequentially formed.
I ₂ O ₃ is deposited to a thickness of 10 nm and Ni-Fe is deposited to a thickness of 40 nm.
Then, for example, Al ₂ O ₃ having a thickness of 20 nm is used as an MR protective layer.
After forming a film by vapor deposition, sputtering, or the like, the MR element 18 having an element width W of 4 μm or less is formed by patterning / ion etching with a photoresist.

Subsequently, as shown in FIGS. 7A and 7B, an insulating layer 19 made of, for example, 500 nm-thick SiO ₂ or the like for insulating the MR element 18 from a bias conductor formed in a process described later. Is formed by sputtering or the like. Then, in order to form an electrode on the side of the MR element 18 which is not the sliding surface, a part of the insulating layer 19 is removed and the electrode connection hole 2 is formed.
Form 0.

Next, the bias conductor 21 is formed on the MR element 18 via the insulating layer 19, and the rear end electrode is electrically connected to the rear end of the MR element 18 via the electrode connection hole 20. 22 is formed. The bias conductor 21 is M
ABS in a direction substantially orthogonal to the longitudinal direction of the R element 18.
Form along the surface. On the other hand, the rear end electrode 22 is formed along the extending direction of the MR element 18. The bias conductor 21 and the rear end electrode 22 are formed into a predetermined pattern by etching Cu or the like after sputtering Cu or the like.

Next, as shown in FIGS. 8 (a) and 8 (b),
In order to insulate the bias conductor 21 and the rear end electrode 22 from the second thin film magnetic core formed in a process described later, an insulating layer 23 made of SiO ₂ or the like is formed to a thickness of about 500 nm by sputtering or the like. . Then, in FIG.
As shown in (a) and (b), in order to form the tip electrode on the ABS surface side of the MR element 18, the insulating layers 19 and 23 are removed and the electrode connection hole 24 is formed. Expose the tip.

Next, as shown in FIG. 10, the non-magnetic and conductive T is formed in the portion where the electrode connection hole 24 is formed.
The film thickness of i etc. is 0.3 μm by sputtering etc.
The film is formed as follows. Then, by patterning with a photoresist, reactive ion etching, or the like, the tip electrode 25 that also functions as the lower gap film.
To form.

Next, as shown in FIGS. 11A and 11B, the second thin film magnetic core 26 is formed by forming Ni--Fe by plating or the like. Then, in order to ground the second thin film magnetic core 26, a ground electrode (GND electrode) is provided on the back side of the second thin film magnetic core 26.
27 is formed.

The MR head is completed through the above steps. Then, an inductive head is formed on the MR head. It should be noted that in describing the method of manufacturing the inductive head, the illustration is omitted. In order to form the inductive head, first, the head winding is formed on the second thin film magnetic core 26 in a spiral shape so as to be completely filled with an insulating layer (all are not shown).

Then, by laminating a third thin film magnetic core (not shown) so as to cover the head winding, an inductive head having a recording magnetic gap formed on the ABS side is completed. After that, MR
A protective layer is formed on the third thin film magnetic core to protect the head and the inductive head.

Finally, A is set so that the recording magnetic gap and the reproducing magnetic gap each have a predetermined depth.
The main surface, which is the BS surface, is polished to complete the composite magnetic head.

[0046]

As is clear from the above description, according to the magnetoresistive effect magnetic head of the present invention, the gap between the MR element and the thin film magnetic cores arranged above and below the MR element, that is, the reproducing gap length is 0. Since the width of the MR element is less than 3 μm and the width of the MR element is less than 4 μm, unnecessary magnetic field in the sliding direction and the track direction can be reduced, and as a result, the SN ratio during reproduction can be significantly improved. You can
Therefore, it is possible to cope with the high rotation of the medium, the short bit of the signal, and the high track density, and it is possible to achieve the high density and high transfer rate of the hard disk drive device.

[Brief description of drawings]

FIG. 1 is an enlarged vertical sectional view of a composite magnetic head.

FIG. 2 is an enlarged transverse cross-sectional view of a main part of a composite magnetic head.

FIG. 3 is an enlarged vertical cross-sectional view of a main part of a composite magnetic head.

4A and 4B sequentially show manufacturing steps of a composite magnetic head, wherein FIG. 4A is an enlarged plan view of an essential part showing a first thin film magnetic core forming step, and FIG. 4B is an enlarged longitudinal sectional view of the essential part. .

5A and 5B sequentially show manufacturing steps of the composite magnetic head, wherein FIG. 5A is an enlarged plan view of an essential part showing a lower gap film forming step, and FIG. 5B is an enlarged longitudinal sectional view of the essential part.

6A and 6B sequentially show manufacturing steps of a composite magnetic head, wherein FIG. 6A is an enlarged plan view of an essential part showing an MR element forming step;
(B) is an enlarged vertical cross-sectional view of the relevant part.

7A and 7B sequentially show manufacturing steps of a composite magnetic head, wherein FIG. 7A is an enlarged plan view of an essential part showing a step of forming a bias conductor and a rear end electrode, and FIG. 7B is an enlarged longitudinal sectional view of the essential part. .

8A to 8C sequentially show a manufacturing process of a composite magnetic head, in which FIG. 8A is an enlarged plan view of an essential part showing an insulating layer forming process;
(B) is an enlarged vertical cross-sectional view of the relevant part.

9A and 9B sequentially show manufacturing steps of a composite magnetic head, in which FIG. 9A is an enlarged plan view of an essential part showing an electrode connection hole forming step, and FIG. 9B is an enlarged longitudinal sectional view of the essential part.

10A and 10B sequentially show manufacturing steps of the composite magnetic head, in which FIG. 10A is an enlarged plan view of an essential part showing a tip electrode forming step;
(B) is an enlarged vertical cross-sectional view of the relevant part.

11A and 11B sequentially show manufacturing steps of the composite magnetic head, in which FIG. 11A is an enlarged plan view of an essential part showing a second thin film magnetic core forming step, and FIG. 11B is an enlarged longitudinal sectional view of the essential part. .

FIG. 12 is a perspective view showing a step of forming a substrate, sequentially showing a manufacturing process of a composite magnetic head in which a conventional MR head and an inductive head are composited.

FIG. 13 is a perspective view showing a head element forming step, which sequentially shows a manufacturing process of a composite type magnetic head in which a conventional MR head and an inductive head are combined.

FIG. 14 is a perspective view showing a step of cutting out a head chip, sequentially showing a manufacturing process of a composite magnetic head in which a conventional MR head and an inductive head are composited.

FIG. 15 is a perspective view showing a suspension attaching step, which sequentially shows a manufacturing process of a composite magnetic head in which a conventional MR head and an inductive head are combined.

FIG. 16 is an enlarged vertical sectional view of a conventional composite magnetic head.

FIG. 17 is an enlarged cross-sectional view of a main part of a conventional composite magnetic head.

FIG. 18 is an enlarged plan view of an essential part of a conventional composite magnetic head.

FIG. 19A is a schematic diagram showing a state where an MR head having a long reproducing magnetic gap receives a magnetic field from a medium,
(B) is a schematic diagram showing a state in which an MR head having a short reproducing magnetic gap receives a magnetic field from a medium.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... ABS surface 2 ... Slider 3a ... Front electrode 3b ... Rear electrode 4 ... MR element 5 ... Bias conductor 7 ... 1st thin film magnetic core 8 ... Second thin film magnetic core 9 ... Third thin film magnetic core 10 ... Magnetically coupled portion 11 ... Head winding

Claims (1)

[Claims] 1. A magnetoresistive effect element arranged such that one edge thereof faces a contact surface with a magnetic recording medium and a longitudinal direction thereof is perpendicular to the contact surface, and the magnetic recording medium. Facing the contact surface of the magnetoresistive effect element, a tip electrode laminated on the tip side of the magnetoresistive effect element, a rear end electrode laminated on the rear end side of the magnetoresistive effect element, and an insulating layer on the magnetoresistive effect element. A bias conductor for applying a bias magnetic field to the magnetoresistive effect element via the magnetoresistive effect element, and a pair of thin film magnetic cores sandwiching the magnetoresistive effect element and the bias conductor, in which the front electrode and the rear end electrode are laminated, are provided. The gap between the magnetoresistive effect element in the same direction as the direction of passing through and the thin film magnetic cores arranged above and below is 0.3 μm.
A magnetoresistive effect magnetic head having a width of m or less and a width of the magnetoresistive effect element in a direction perpendicular to a direction of passing over the medium being 4 μm or less.