JPH11110715A - Magnetic head and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize excellent recording/reproducing characteristics of a magnetic head and reduce the variation in characteristics of the individual heads. SOLUTION: A pair of magnetic half cores are joined integrally with each other so as to have their magnetic gap forming surfaces abut upon each other. Metal magnetic films 5 and 6 are formed on the magnetic gap forming surfaces of the magnetic half cores. The metal magnetic films 5 and 6 are composed of layered magnetic layers 14, 15, 16 and 17 which are made of material whose composition is expressed by a formula Fex My Az (wherein M denotes at least one of elements Ta, Zr, Hf Nb and Ti, A denotes at least one of elements N, C and B, 71<=x<=85, 6<=y<=15 and 9<=z<=16). The uppermost magnetic layers 16 and 17 among the magnetic layers 14, 15, 16 and 17 have positive magnetic distortions, the lowermost magnetic layers 14 and 15 opposite to the uppermost magnetic layers have negative magnetic distortions and, further, the absolute values of the respective magnetic distortions are not larger than 7×10<-7> . These requirements can be achieved by applying a heat treatment every time after the respective magnetic layers 14, 15, 16 and 17 are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head suitable for a high coercive force magnetic recording medium such as a metal tape, which is used for a video tape recorder or a data storage device for recording / reproducing in a helical scan system. More particularly, the present invention relates to improvement of a metal magnetic film constituting a magnetic gap portion.

[0002]

2. Description of the Related Art In recent years, in the field of magnetic recording, the density of recording signals has been increasing, and a magnetic recording medium having a high coercive force and a high residual magnetic flux density, such as a ferromagnetic metal material, has been used as a non-magnetic support. Metal tapes and the like directly adhered on top have been used. Accordingly, the core material is required to have a high saturation magnetic flux density and a high magnetic permeability for the magnetic head.

In order to satisfy such requirements, ferrite has been conventionally used as an auxiliary core material, a metal magnetic film having a high saturation magnetic flux density is formed as a main core material on the ferrite, and a magnetic gap portion is formed on the metal core. Metal-in-gap (Metal i gap) formed by a magnetic film
An n Gap) type magnetic head (hereinafter, referred to as an MIG head) has been proposed, which is suitable for recording / reproducing a metal tape or the like.

In this type of magnetic head, with the recent remarkable progress of high recording density, in order to perform better recording / reproducing on a magnetic recording medium having a high coercive force such as the above-mentioned metal tape, It is required to use a metal magnetic material having a higher saturation magnetic flux density for obtaining a sufficient recording magnetic field and having excellent soft magnetic properties.

Therefore, in recent years, a so-called precipitation type microcrystalline metal magnetic film containing Fe as a main component has a high saturation magnetic flux density and exhibits excellent soft magnetic characteristics in an in-plane direction. Practical use has begun in the form of replacing metal magnetic materials. The precipitation-type microcrystalline metal magnetic film is generally formed by dispersing and depositing fine crystal grains based on Fe by forming a non-crystalline film and then performing a heat treatment.

[0006]

When the above-mentioned microcrystalline metal magnetic film is applied as a metal magnetic material for a MIG type magnetic head, the soft magnetism of the microcrystalline metal magnetic thin film depends on the film forming conditions and heat treatment conditions. Has properties that are greatly affected. Therefore, in order to prevent magnetic deterioration of the metal magnetic film and prevent the flow of magnetic flux from being limited to one direction, an appropriate heat treatment condition has been found so as to make the magnetostriction substantially close to zero.

However, the adjustment of the magnetostriction is limited to about ± 3 to ± 3 due to subtle variations due to target consumption during sputter deposition, subtle variations in heat absorption during heat treatment, etc. Control was only possible at about 5 × 10 ⁻⁷ , and it was difficult to control delicately. In addition, variations due to the degree of these deviations occur for each individual head, which is a problem.

Furthermore, even if the magnetostriction is controlled to be sufficiently small,
Since the film itself has the same magnetostriction, the magnetic anisotropy of the metal magnetic film in a specific direction is reduced due to residual stress on the metal magnetic film and anisotropy induced by various factors in the metal magnetic film. There is a problem that the recording and reproduction characteristics of the head are deteriorated.

The present invention has been proposed in order to solve the above-mentioned problems, and delicately controls the magnetostriction of the metal magnetic film to reduce the influence of the deviation due to the heat treatment. It is an object of the present invention to provide a magnetic head which can avoid the influence of magnetic anisotropy and has excellent recording / reproducing characteristics, and a method for manufacturing the same.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the magnetostriction of the microcrystalline metal magnetic film containing Fe as a main component depends on the temperature of the heat treatment. Paying attention to the decrease and further decreasing depending on the logarithm of the heat treatment time, the microcrystalline metal magnetic film is divided into a plurality of times and formed, and the heat treatment is performed for each magnetic layer formation, so that each magnetic layer is formed. By changing the magnetostriction in the film thickness direction from positive to negative, it was found that the magnetostriction of the entire magnetic layer can be finely controlled.

That is, in the magnetic head according to the present invention, a pair of magnetic core halves are joined and integrated by abutting the magnetic gap forming surfaces, and the magnetic core of at least one of the pair of magnetic core halves is magnetically integrated. A metal magnetic film is formed on the gap forming surface. And, the metal magnetic film,
Fe _x M _y A _z (however, M is Ta, Zr, Hf, Nb,
A is at least one of Ti, A is at least one of N, C, and B, x, y, and z are atomic fractions, each of which is 71 ≦ x ≦ 85, 6 ≦ y ≦ 1
5, 9 ≦ z ≦ 16. ) Is formed by laminating a plurality of magnetic layers having the composition represented by the formula (1), and among the laminated magnetic layers, the uppermost magnetic layer on the magnetic gap side shows a positive magnetostriction, and is opposite to the uppermost magnetic layer. And the absolute value of each magnetostriction is 7 × 1.
^0-7 or less.

As described above, by changing the magnetostriction of each magnetic layer from the uppermost magnetic layer to the lowermost magnetic layer from positive to negative, the apparent magnetostriction of the entire metal magnetic film can be controlled to be small. And the influence of deviation of heat treatment conditions can be reduced. Further, by changing the magnetostriction between the respective magnetic layers as described above, a change in magnetic characteristics occurs in the metal magnetic film in a fluctuating manner. The influence of the magnetic anisotropy of the magnetic film induced at the time of or during the heat treatment can be avoided, and the flow of the magnetic flux is not limited to a certain direction. As a result, the recording / reproducing characteristics of the head are improved, and variations among heads are eliminated.

Here, when the absolute value of the magnetostriction exceeds 7 × 10 ⁻⁷ , the influence of the magnetostriction of each magnetic layer greatly appears even when averaged, and the magnetic domain structure is disturbed. Is fixed and the magnetization is hard to rotate, and noise or the like is generated by contact with the recording medium.

Further, in the magnetic head according to the present invention, by leaving a compressive stress in the metal magnetic film, the anisotropy in which the direction of hard magnetization becomes more in-plane in the direction near the uppermost magnetic layer where the magnetostriction is positive. Anisotropy occurs in which the magnetization direction becomes more difficult in the film thickness direction near the lowermost magnetic layer where the magnetostriction is negative. As a result, the magnetic flux is easily transmitted to the magnetic gap surface, and the leakage of the magnetic flux in the magnetic gap is easily promoted, so that the recording / reproducing characteristics of the head are further improved.

Further, in the magnetic head according to the present invention, Rh, Pd, Ag, Ir, P
By laminating at least one intermediate layer composed of at least one of t and Au, the orientation of the metal magnetic film is adjusted and the recording / reproducing characteristics are further improved.

On the other hand, in the method of manufacturing a magnetic head according to the present invention, a pair of magnetic core halves are joined and integrated by abutting a magnetic gap forming surface, and at least one of the pair of magnetic core halves is joined. in the metallic magnetic film in the magnetic gap forming surface of the body to produce a magnetic head formed by deposition, Fe _x M _y a _z (however, M is Ta, Zr, H
at least one of f, Nb, Ti, A is at least one of N, C, B, x, y, z
Represents an atomic fraction, and these are respectively 71 ≦ x ≦ 8
5, 6 ≦ y ≦ 15, 9 ≦ z ≦ 16. ), A metal magnetic film having the composition shown in (1) is divided into a plurality of times to form a film, and heat treatment is performed after each of the divided magnetic layers is formed. Then, the magnetostriction of the uppermost magnetic layer on the magnetic gap side indicates positive, the magnetostriction of the lowermost magnetic layer on the opposite side to the uppermost magnetic layer indicates negative, and the absolute value of each magnetostriction is 7 ×
It is characterized in that it is 10 ^-7 or less.

In the method of manufacturing a magnetic head according to the present invention, the metal magnetic film is divided into a plurality of times, and a heat treatment is applied to each of the divided magnetic layers.
The magnetostriction of the lowermost magnetic layer formed first is defined as negative, the magnetostriction of the uppermost magnetic layer on the magnetic gap side formed last is defined as positive,
By setting the absolute value of each magnetostriction to 7 × 10 ⁻⁷ , the apparent magnetostriction of the entire metal magnetic film can be controlled to be small, and the influence of the deviation of the film forming conditions and the heat treatment conditions can be reduced. Further, by changing the magnetostriction between the respective magnetic layers in this manner, a change in magnetic properties occurs in the metal magnetic film in a fluctuating manner. Therefore, unlike the case where a single metal magnetic film is formed, the magnetic film is formed. The influence of the magnetic anisotropy of the magnetic film induced at the time of or during the heat treatment can be avoided, and the flow of the magnetic flux is not limited to a certain direction. As a result, the recording / reproducing characteristics of the head are improved, and variations among heads are eliminated.

Further, in the method of manufacturing a magnetic head according to the present invention, by leaving a compressive stress in the metal magnetic film, the near-uppermost magnetic layer having a positive magnetostriction becomes more difficult to magnetize in the in-plane direction. Anisotropy occurs, and anisotropy occurs in which the direction of magnetization is more difficult in the thickness direction near the lowermost magnetic layer where the magnetostriction is negative. As a result, the magnetic flux is easily transmitted to the magnetic gap surface, and the leakage of the magnetic flux in the magnetic gap is easily promoted, so that the recording / reproducing characteristics of the head are further improved.

In the method of manufacturing a magnetic head according to the present invention, the metal magnetic film may include Rh, Pd, Ag, and I.
By laminating at least one intermediate layer composed of at least one of r, Pt, and Au, the orientation of the metal magnetic film is adjusted, and the recording / reproducing characteristics are further improved.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of a magnetic head to which the present invention is applied will be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, the magnetic head according to the present embodiment has a pair of magnetic heads separately formed on the left and right sides of a magnetic gap g located substantially at the center of the surface in contact with the magnetic recording medium. The core halves 1 and 2 are joined and integrated by abutting the magnetic gap forming surfaces, which are abutting surfaces, at positions where the track width portions coincide.

The magnetic core halves 1 and 2 are composed of magnetic core bases 3 and 4 as auxiliary cores and metal magnetic films 5 and 6 as main cores. The magnetic core bases 3, 4
Is made of a soft magnetic oxide material such as Mn-Zn based ferrite or Ni-Zn based ferrite, and serves as an auxiliary core portion that forms a closed magnetic circuit together with the metal magnetic films 5 and 6. The surfaces of the magnetic core substrates 3 and 4 facing the magnetic gap forming surface have a track width T of the magnetic gap g.
w, groove width regulating grooves for regulating w
Are formed in an arc shape in the depth direction from the vicinity of both ends of the magnetic gap g. The track width regulating grooves 7, 8, 9 and 10 are filled with a non-magnetic material 11 such as glass for the purpose of securing the contact characteristics with the magnetic recording medium and preventing uneven wear due to sliding contact. Have been.

The surfaces of the magnetic core substrates 3 and 4 facing the magnetic gap forming surface are provided with the magnetic gap g.
The winding grooves 12 and 13 for winding a coil (not shown) are formed so as to have a substantially rectangular side surface.

On the other hand, the metal magnetic films 5 and 6 serve as a main core portion constituting a closed magnetic circuit together with the magnetic core bases 3 and 4, and are formed over the entire surface including the magnetic gap forming surface. In FIG. 1, the metal magnetic films 5 and 6 are formed not only on the magnetic gap forming surface but also on the track width regulating grooves 7 and 8.
Although the case where the film is formed over the entire surface inside the winding grooves 12 and 13 in 9, 10 and the winding grooves 12 and 13 is shown, if the film is formed on the gap surface, the other portions inside the groove are formed by mask sputtering or the like. It is also possible to adopt a configuration in which a film is not formed by a technique.

In the present invention, the metal magnetic films 5, 6
Are the first magnetic layers 14 and 15 and the second magnetic layer 1 respectively.
6 and 17. The first magnetic layers 14 and 15 and the second magnetic layers 16 and 17 are composed of Fe _x
M _y A _z (however, M is at least one of Ta, Zr, Hf, Nb, Ti, A is at least one of N, C, B, x, y, z are atomic Rate,
These are respectively 71 ≦ x ≦ 85, 6 ≦ y ≦ 15,9
≦ z ≦ 16. ), The magnetostriction of the second magnetic layers 16 and 17 on the magnetic gap side becomes positive,
The magnetostriction of the first magnetic layers 14 and 15 on the opposite side is negative, and the absolute value of each magnetostriction is 7 × 10 ⁻⁷ .

With such a configuration, the magnetostriction of the first magnetic layers 14 and 15 and the magnetostriction of the second magnetic layers 15 and 16 influence each other, and the apparent appearance of the metal magnetic films 5 and 6 is increased. The overall magnetostriction is reduced. Each of the magnetic layers 14, 15, 16,
When the product of the film thickness and magnetostriction of No. 17 is averaged, -3 × 10 ^-7
+ 3 × 10 ^-7 can be suppressed. Here, when the absolute value of the magnetostriction exceeds 7 × 10 ⁻⁷ , the influence of the magnetostriction of each magnetic layer is large even when averaged, the magnetic domain structure is disturbed, and the magnetization direction is fixed by the inverse magnetostriction effect. There is a possibility that noise or the like may be generated due to contact with the recording medium, which makes the magnetization difficult to rotate.

Thus, each of the magnetic layers 14, 15, 16,
By changing the magnetostriction 17 from positive to negative, the apparent overall magnetostriction of the metal magnetic films 5 and 6 can be suppressed to near zero, and the influence of a shift in heat treatment or the like can be reduced. Further, by adopting such a configuration, a change in magnetic characteristics occurs in the metal magnetic films 5 and 6 in a fluctuating manner. The influence of anisotropy can be avoided, and the flow of magnetic flux is not limited to a certain direction. As a result, the recording / reproducing characteristics of the head are improved, and variations among heads are eliminated.

Further, the metal magnetic films 5 and 6 exhibit characteristics as shown in FIG. 3 when the compressive stress is left. That is, in the first magnetic layers 14 and 15 having a negative magnetostriction, the in-plane direction of the plane serving as the magnetic gap becomes the easy magnetization direction,
The magnetic permeability in the film thickness direction (the direction of the arrow in the figure) increases. On the other hand, in the second magnetic layers 16 and 17 in which the magnetostriction is positive, the in-plane direction of the magnetic film becomes a difficult magnetization direction, and the magnetic permeability in the in-plane direction (the direction of the arrow in the drawing) increases. As a result, at the time of recording,
The magnetic flux transmitted through the bases 3 and 4, such as ferrite, is easily transmitted to the surface of the magnetic gap g by the first magnetic layers 14 and 15, and is easily leaked from the magnetic gap g by the second magnetic layers 16 and 17. And the recording efficiency is increased. Similar effects can be expected reversibly during reproduction. As described above, the effect between the stress of the metal magnetic film and the magnetostriction of the magnetic film causes the metal magnetic film 5,
The soft magnetism of No. 6 is suitable for a magnetic head.

The first magnetic layers 14 and 15 and the second magnetic layers 16 and 17 have a smaller film thickness than that of Rh,
A multilayer structure may be obtained by stacking at least one or more intermediate layers containing at least one of Pd, Ag, Ir, Pt, and Au. Thus, each magnetic layer has 14, 15,
By laminating an intermediate layer on each of the magnetic layers 1 and 16,
The orientation of 4, 15, 16 and 17 is adjusted, the lattice spacing is widened, and the soft magnetic characteristics suitable for heading are improved.

In order to enhance the laminating effect, the thickness of the intermediate layer is 0.2 to 10 nm, and the laminating interval is 0.05 to 10 nm.
It is preferably 1 μm. If the ratio of the intermediate layer is too large, the soft magnetic characteristics are rather deteriorated.

The first magnetic layers 14, 15 and the base 3,
In order to prevent a chemical reaction such as oxygen transfer occurring at the interface between the magnetic layer and the base between the magnetic layer and the base and prevent the formation of a reaction layer that interferes with the magnetic flux generated from the original magnetic gap g, Compounds such as SiO ₂ , Si ₃ N, and Al ₂ O ₃ or a stacked film of these compounds and the above-described metals may be provided as a base film.

The magnetostriction of each of the magnetic layers 14 and 15 can be quantitatively measured by detecting the occurrence of warpage due to a bimetallic effect with the substrate when the magnetic layers expand and contract by the applied magnetic field. it can. Typical examples of warp detection include a capacitance detection type and a light reflection angle detection type. The magnetostriction of each magnetic layer can also be obtained by using the effects of magnetostriction and stress to evaluate how the slope of the BH curve changes when stress is applied to the magnetic layer.

From the viewpoint of ease of use, for measuring the magnetostriction of the magnetic layer, for example, a light reflection angle detecting type measuring device as shown in FIG. 4A is often used. The light reflection angle detection type device 30 emits a laser spot light having a small diameter to a free end side of the sample 31, a magnetized coil 32 for generating a magnetic field, and a sample 31 arranged in a cantilever shape. Laser light source 33
And a photodetector 3 for detecting a reflected laser beam from the sample 31
4 is provided. The sample 31 has a magnetic layer 36 formed on a substrate 35 having a known Young's modulus. In the light reflection angle detection type device 30, as shown in FIGS. 4B and 4C, the reflection position of the laser beam applied to the magnetic layer 36 of the sample 31a in the non-magnetized state is determined by the photodetector 34. The deflection of the sample 31b at the time of magnetization is detected by detecting the reflection position of the laser beam applied to the magnetic layer 36 of the sample 31b at the time of magnetization, and the magnetic layer 3 is determined by the Young's modulus of the substrate 35 and the magnetic layer 36.
6, that is, the magnetostriction of the magnetic layer 36 can be obtained.

Next, a method for manufacturing the above-described magnetic head will be specifically described.

First, as shown in FIG. 5, for example, Mn-Z
Made of an oxide soft magnetic material such as n-type ferrite or Ni-Zn-type ferrite, for example, a length of 34.5 mm and a width of 2.5
A plate-shaped substrate 20 having a thickness of about 1 mm and a thickness of about 1 mm is prepared. Next, as shown in FIG. 6, a plurality of track width regulating grooves 21 having a substantially semicircular cross section are formed in the width direction of the main surface of the base 20.
An interval (21 μm) equal to a predetermined track width is formed between the track width regulating grooves 21.

The angle of the side surface at the portion in contact with the main surface of the track width regulating groove 21 is usually about 8 to 45 °, but may be 90 °. The depth of the track width regulating groove 21 is 200 to 300 μm, and the cross-sectional shape of the groove is U-shaped in the figure, but may be V-shaped or polygonal. However, when the angle is small, the electromagnetic conversion efficiency is reduced, and when the angle is large, the possibility of reading a signal from a track other than the target on the recording medium is increased. As a result, noise is increased. .

Next, as shown in FIG. 7, the gap depth of the magnetic gap is regulated, and a winding groove 22 for winding the winding is formed. Then, the surface of the substrate 20 is polished so that the surface roughness becomes about 20 to 100 Å.

Next, to the substrate 20 formed as described above, Fe _x M _y A _z (however, M is Ta, Zr, H
at least one of f, Nb, Ti, A is at least one of N, C, B, x, y, z
Represents an atomic fraction, and these are respectively 71 ≦ x ≦ 8
5, 6 ≦ y ≦ 15, 9 ≦ z ≦ 16. A metal magnetic film having the composition shown in (1) is formed. As shown in FIG. 8, the metal magnetic film having such a composition tends to decrease the magnetostriction due to the heat treatment depending on the temperature of the heat treatment, and further to decrease depending on the logarithm of the heat treatment time.

Therefore, in the present invention, for example, to form a metal magnetic thin film, first, a first magnetic layer is formed and heat-treated, and then a second magnetic layer is formed on the first magnetic layer. The first magnetic layer is made negative in magnetostriction, the magnetostriction in the second magnetic layer is made positive, and the absolute value of each magnetostriction is set to 1 × 10 ^{−. 7} or less.

For example, a target containing 13 atomic% of Fe with respect to Fe is used, and N (nitrogen) is 30% in Ar.
Sputtering was performed in the contained atmosphere.
(A) As shown in (b), a first magnetic layer 23 is formed on the surface of the base 20 by a thickness of about half of a specified total thickness of 5 μm.
Form a film with a thickness of μm.

At this time, in order to adjust the orientation of the first magnetic layer 23, the first magnetic layer 23 is formed while an intermediate layer having a thickness of 15 nm is laminated every 0.4 μm. Also,
In order to prevent a reaction at the interface between the base 20 and the first magnetic layer 23, a 5-nm thick SiO ₂ film is formed between the base 20 and the first magnetic layer 23.

Then, for the first magnetic layer 23, 50
Heating is performed at 0 ° C. in a vacuum for 2000 minutes to perform a heat treatment.

Subsequently, the substrate 20 is returned into the film forming apparatus, and a second magnetic layer 24 is formed on the first magnetic layer 23 as shown in FIGS. A film is formed with a thickness of 2.5 μm.

Before the formation of the second magnetic layer 24, reverse sputtering is performed to remove the oxide film by heat treatment on the surface of the first magnetic layer 23, and the initial layer of the second magnetic layer 24 is removed. In order to adjust the orientation, a Pt layer having a thickness of 0.4 μm is preferably formed. Then, similarly to the first magnetic layer 23, the second magnetic layer 24 is formed while laminating an intermediate layer having a thickness of 15 nm every about 0.4 μm. Then, as shown in FIGS. 11 (a) and 11 (b), a gap film 25 made of SiO ₂ is formed on the second magnetic layer so as to have a thickness which is about half the prescribed magnetic gap length for each core half. I do.

At this stage, as shown in FIG. 12, the base 26 having the same winding groove as that of the base 20 is attached to the gap film 2.
5, the positioning was performed such that the track width regulating grooves 21 coincided with each other, and the end faces were abutted. Then, the non-magnetic glass 27 is sandwiched in the winding groove 22,
0 minute heat treatment is applied to soften and melt the glass,
0 and 26 were joined and integrated. Lastly, the surface of the joined base that is in contact with the magnetic recording medium is cylindrically ground and machined into an appropriate shape, and at the positions indicated by dotted lines a, b, c, d, and e in FIG. By performing slicing, the magnetic head as shown in FIGS. 1 and 2 is completed.

As a result, as shown in FIG. 13, the first magnetic layer 23 is affected by heat at 500 ° C. for 2000 minutes and 100 minutes, and its magnetostriction becomes −3 × 10 ⁻⁷ , The second magnetic layer 224 was affected by heat at 500 ° C. for 100 minutes, and its magnetostriction became + 4 × 10 ⁻⁷ . Then, the magnetostriction of each other affects each other, the apparent overall magnetostriction of the metal magnetic film becomes small, and when the product of each magnetic layer and the magnetostriction is averaged,
[(−3 × 10 ⁻⁷ × 2.5 μm) + (4 × 10 ⁻⁷ × 2.
5 μm)] / 5 μm = 0.5 × 10 ⁻⁷ , which is extremely close to zero.

Further, as described above, in the metal magnetic film,
Changes in magnetic characteristics occur in a fluctuating manner, and the direction in which magnetic flux flows is not affected by deviations in film formation conditions or heat treatment conditions, and stable head characteristics can be obtained, and variations among individual heads can be obtained. Is obtained.

Further, when compressive stress is left in the metal magnetic film, for example, the total gas pressure during sputtering during the formation of the metal magnetic film is reduced, the substrate temperature during the film formation is reduced, or the coefficient of thermal expansion is reduced. If you choose a large substrate,
As described above, the soft magnetism of the metal magnetic film becomes suitable for the magnetic head due to the effect between the stress of the magnetic film and the magnetostriction of the magnetic film. That is, as shown in FIG. 3, in the first magnetic layers 14, 15 (23), since the magnetostriction is negative, the in-plane direction of the plane that becomes a magnetic gap due to the application of compressive stress becomes the easy magnetization direction, The magnetic permeability in the film thickness direction (the direction of the arrow in the figure) increases. On the other hand, the second magnetic layers 16, 17 (24)
In this case, since the magnetostriction is positive, when a compressive stress is applied, the in-plane direction of the magnetic film becomes a difficult magnetization direction, and the magnetic permeability in the in-plane direction (the direction of the arrow in the drawing) increases. As a result, at the time of recording, the magnetic flux transmitted through the base 3 (20), such as ferrite, is easily transmitted to the magnetic gap g surface by the first magnetic layers 14, 15 (23), and the second magnetic layer 16, 20 17 (24)
As a result, the recording efficiency is increased because the leakage from the magnetic gap g is facilitated. Similar effects can be expected reversibly during reproduction.

As described above, after the first magnetic layer 23 and the second magnetic layer 24 are formed, a heat treatment is applied, and the total gas pressure during sputtering is controlled to be low to form a metal magnetic film. In the case of the production, the output was improved by 0.5 dB as compared with the case where the heat treatment step was not interposed during the formation of the metal magnetic film. Also, the variation among the individual magnetic heads due to the variation in the film forming conditions and the heat treatment conditions of the metal magnetic film was improved by 30% in the standard deviation value as compared with the conventional case.

Further, as described above, the first magnetic layer 23
By stacking a plurality of intermediate Pt layers (Rh, Pd, Ag, Ir, Au) with a smaller thickness on the second magnetic layer 24, the thickness of each of the magnetic layers 23, 24 is reduced. The orientation is adjusted, and the head characteristics can be further improved.

In the present embodiment, the metal magnetic film is divided into the first magnetic layer and the second magnetic layer. However, in the present invention, the metal magnetic film is divided into three or more layers, and after each magnetic layer is formed. It goes without saying that a series of metal magnetic films may be formed while performing heat treatment every time.

Furthermore, in the present embodiment, the magnetostriction of each magnetic layer is adjusted by adjusting only the heat treatment time, but in the present invention, the magnetostriction is adjusted by adjusting both the heat treatment time and the heat treatment temperature. Of course, you may do it.

Further, in this embodiment, the case where the winding groove is formed in the core half on both sides is shown, but in the present invention, it is needless to say that the winding groove may be formed only in the core half on one side. .

In the present embodiment, the case where the metal magnetic film is formed on the core half after the formation of the winding groove has been described. However, the magnetic film may be formed before the formation of the winding groove. When a magnetic film is formed after the formation of the winding groove, a non-magnetic substrate such as a ZrO ₂ substrate may be used as the substrate.

[0055]

As is apparent from the above description, according to the magnetic head of the present invention, the metal magnetic film constituting the magnetic gap is constituted by a plurality of magnetic layers, and the magnetostriction is reduced in the thickness direction. Since it is changed from positive to negative, the apparent magnetostriction of the entire metallic magnetic film can be finely controlled, and the influence of magnetic anisotropy due to a shift in manufacturing conditions can be avoided. Therefore, in this magnetic head, the recording / reproducing characteristics of the head are improved, and variations between heads are eliminated.

Further, according to the method of manufacturing a magnetic head of the present invention, the metal magnetic film constituting the magnetic gap is divided into a plurality of times to form a film, and after each of the divided magnetic layers is formed, Since the heat treatment is performed, the effect of the cumulative heat treatment applied to each magnetic layer changes, and the magnetostriction in the thickness direction of the metal magnetic film changes from positive to negative. As a result, the apparent total magnetostriction of the metal magnetic film can be controlled to be small, the influence of magnetic anisotropy due to the deviation of the manufacturing conditions is avoided, the recording / reproducing characteristics of the head are improved, and the variation between individual heads is reduced. Can be eliminated.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a magnetic head to which the present invention is applied.

FIG. 2 is an enlarged plan view showing a main part of the magnetic head in contact with a recording medium.

FIG. 3 is a schematic diagram showing a direction in which magnetic permeability is high when a compressive stress is applied to a metal magnetic film (first magnetic layer and second magnetic layer) of the magnetic head.

4A and 4B are diagrams illustrating a method for measuring magnetostriction, FIG. 4A is a schematic diagram illustrating a reflection angle detection type measuring device, FIG. 4B is a schematic diagram illustrating a sample in a non-magnetized state, and FIG. () Is a schematic diagram showing a sample at the time of magnetization.

FIG. 5 is a diagram illustrating a manufacturing process of the magnetic head.
It is a perspective view showing a substrate.

FIG. 6 is a diagram illustrating a manufacturing process of the magnetic head.
It is a perspective view which shows a track width groove | channel input process.

FIG. 7 is a diagram for explaining a manufacturing process of the magnetic head.
It is a perspective view which shows a winding groove | channel input process.

FIG. 8 is a characteristic diagram showing a relationship between a magnetostriction of a metal magnetic film of the magnetic head and a logarithm of a heat treatment time.

FIG. 9 is a diagram illustrating a manufacturing process of the magnetic head.
(A) is a perspective view showing a step of forming a first magnetic layer,
(B) is an enlarged plan view of the main part.

10A and 10B are diagrams illustrating a manufacturing process of the magnetic head, wherein FIG. 10A is a perspective view illustrating a process of forming a second magnetic layer, and FIG. 10B is an enlarged plan view of a main part thereof.

11A and 11B are diagrams illustrating a manufacturing process of the magnetic head, wherein FIG. 11A is a perspective view illustrating a process of forming a gap film, and FIG. 11B is an enlarged plan view of a main part thereof.

FIG. 12 is a diagram illustrating a manufacturing process of the magnetic head, and is a perspective view illustrating a bonding process using non-magnetic glass and a cutting position when the head is formed.

FIG. 13 is a characteristic diagram showing a change in magnetostriction depending on a heat treatment time of a metal magnetic film of the magnetic head.

[Explanation of symbols]

1,2 magnetic core half, 3,4,20 substrate, 5,6 metal magnetic film, 7,8,9,10,21 track regulating groove,
1,27 non-magnetic glass, 12,13,22 winding groove, 1
4, 15, 23 First magnetic layer, 16, 17, 24 Second magnetic layer

Claims (6)

[Claims] 1. A pair of magnetic core halves are joined and integrated by abutting magnetic gap forming surfaces, and a metal magnetic film is formed on a magnetic gap forming surface of at least one of the pair of magnetic core halves. in the magnetic head formed by deposition, the metal magnetic film, Fe _x M _y A _z (however, M is Ta,
Z is at least one of Zr, Hf, Nb, and Ti; A is at least one of N, C, and B;
x, y, and z indicate the atomic fraction, which are respectively 71%
≤ x ≤ 85, 6 ≤ y ≤ 15, 9 ≤ z ≤ 16. ) Is formed by laminating a plurality of magnetic layers having the composition represented by the formula (1). Of the plurality of laminated magnetic layers, the magnetostriction of the uppermost magnetic layer on the magnetic gap side indicates positive, A magnetic head wherein the magnetostriction of the lowermost magnetic layer is negative, and the absolute value of each magnetostriction is 7 × 10 ⁻⁷ or less. 2. The magnetic head according to claim 1, wherein a compressive stress remains in the metal magnetic film. 3. The metal magnetic film according to claim 1, wherein Rh, Pd, A
2. The magnetic head according to claim 1, wherein at least one intermediate layer made of at least one of g, Ir, Pt, and Au is laminated. 4. A pair of magnetic core halves are joined and integrated by abutting a magnetic gap forming surface, and a metal magnetic film is formed on a magnetic gap forming surface of at least one of the pair of magnetic core halves. in the production of the formed magnetic head comprising, Fe _x M _y a _z (however, M is Ta, Zr, Hf, Nb,
A is at least one of Ti, A is at least one of N, C, and B, x, y, and z are atomic fractions, each of which is 71 ≦ x ≦ 85, 6 ≦ y ≦ 1
5, 9 ≦ z ≦ 16. ) Is formed by dividing the metal magnetic film having the composition represented by the formula into a plurality of times, and performing a heat treatment after each of the divided magnetic layers is formed, whereby the magnetostriction of the uppermost magnetic layer on the magnetic gap side is reduced. The magnetic head according to claim 1, wherein the magnetostriction of the lowermost magnetic layer opposite to the uppermost magnetic layer is negative, and the absolute value of each magnetostriction is 7 × 10 ⁻⁷ or less. Production method. 5. The method of manufacturing a magnetic head according to claim 4, wherein a compressive stress is left on the metal magnetic film. 6. The method according to claim 6, wherein Rh, Pd, A
5. The method according to claim 4, wherein at least one intermediate layer made of at least one of g, Ir, Pt, and Au is formed.