JPH053121A - Magnetic member - Google Patents

Abstract

PURPOSE:To obtain a magnetic film or a magnetic member, having a high saturated magnetic flux density Bs and a low coercive force Hc characteristic, which is suitable for the constitution of a magnetic head and the like. CONSTITUTION:The title magnetic member is the alloy magnetic film shown by a general formula MM'N (where the M denotes at least one of the transition metal of Co and Fe, M' denotes the element containing at least one kind selected from B, A, Si, Ga, Ge, Ti, Zr, Hf, Nb, Ta, Mo and W, and N denotes nitrogen), and the concentration of M' or N in the alloy magnetic film is characteristically made relatively higher on one main surface. Accordingly, when the magnetic film or magnetic member is used for constitution of a magnetic head while high saturated magnetic flux density Bs exceeding 1.7T is being maintained, the magnetic film or magnetic member displays excellent recording efficiency and reproduction capacity because it has no false gap.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic member, and more particularly to a magnetic member (magnetic film) suitable for the construction of a magnetic head.

[0002]

2. Description of the Related Art In order to sufficiently exert the recording (reading) capability (function) for a magnetic recording medium having a high coercive force Hc, for example, a magnetic film or a magnetic layer forming a magnetic head has a high saturation magnetic flux density Bs and a soft magnetic flux density Bs. It is required to have magnetic properties (low coercive force Hc).

Incidentally, NiFe alloy films, FeAlSi-based alloy films, and the like are conventionally known as crystalline magnetic films exhibiting good soft magnetic characteristics. However, the saturation magnetic flux density Bs of these magnetic films is about 1.1 T at the maximum, which is not sufficient for a magnetic head configuration for a magnetic recording medium having a high coercive force Hc. In addition, many Fe-based or Co-based alloys exhibit a low coercive force Hc by becoming amorphous. However, the saturation magnetic flux density Bs is lowered by the addition of an element for making it amorphous, and further considering the heat resistance, the saturation magnetic flux density Bs becomes about 1T. On the other hand, a CoFe-based alloy film or Fe-based alloy film containing crystalline A1 has a high saturation magnetic flux density B of 1.5 T or more.
Since s is shown, it is suitable for use as a magnetic head for a magnetic recording medium having a high coercive force Hc.

[0004]

However, the inventors of the present invention further conducted extensive studies on the CoFe-based alloy magnetic film and the Fe-based alloy magnetic film containing the crystalline A1 as described above.
When the saturation magnetic flux density Bs is increased by reducing the addition amount of the third element, the coercive force H as a whole in the case of a film having a thickness of several μm or more.
Although c was low, it was confirmed that the coercive force Hc in the initial formation layer of the magnetic film formed by sputtering was deteriorated. Therefore, when an alloy magnetic film of this kind is used to manufacture, for example, an MIG head, it causes a pseudo gap, resulting in ripples in the frequency characteristic of the output, and a serious problem that a good reproducing characteristic cannot be obtained. Has a drawback that it is apt to occur.

Further, for a CoFe alloy magnetic film containing a transition metal that promotes amorphization, when the film formation is carried out by sputtering, for example, the substrate temperature rises in the latter stage of film formation and crystal grain growth occurs and Hc of Hc increases. There is a problem that deterioration easily occurs.

It is an object of the present invention to provide a magnetic film or a magnetic member which has a higher saturation magnetic flux density Bs and, on the other hand, exhibits a low coercive force Hc characteristic and which is suitable for a magnetic head or the like. Further, another object of the present invention is to provide a magnetic film capable of suppressing the generation of a deteriorated layer at the initial stage of growth of the magnetic film.

[0007]

A magnetic member (magnetic film) according to the present invention has a general formula: MM'N (where M is at least one of Co and Fe).
Species of transition metals, M'is B, Al, Si, Ga, Ge, T
i, Zr, Hf, Nb, Ta, Mo, W, N is nitrogen, and the alloy-based magnetic film is M ′ or M ′ in the alloy-based magnetic film. The N concentration is relatively high on the one main surface side.

In other words, at least one transition metal selected from the group consisting of Co and Fe and B, Al and S
i, Ga, Ge, Ti, Zr, Hf, Nb, Ta, M
An alloy-based magnetic body (film or member) composed of nitrogen and at least one element selected from the group X consisting of o and W, wherein one main surface side, for example, a support substrate side, has the above X component concentration. Alternatively, the alloy-based magnetic film (magnetic member) is characterized in that the nitrogen concentration is high and the X component concentration or the nitrogen concentration decreases on the other main surface side, for example, in the film thickness direction.
The alloy type magnetic film or magnetic member according to the present invention is manufactured as follows. That is, in a sputtering gas containing nitrogen, at least one transition metal M selected from the group consisting of Co and Fe and B, Al, Si and G.
It is produced by sputtering a metal composed of at least one element selected from the group M ′ consisting of a, Ge, Ti, Zr, Hf, Nb, Ta, Mo and W. In this sputtering process,
(a) In the initial stage of sputtering, a target having a different concentration of M ′ (X) is used compared to the latter stage of sputtering, or (b) The sputtering conditions in the initial stage of sputtering are compared with those in the latter stage of sputtering. , At least M'of the film composition
Sputtering is performed under the condition of different (X) concentration or nitrogen (N) concentration.

[0009]

The function of the alloy-based magnetic film (magnetic member) according to the present invention is C
at least one transition metal M selected from the group consisting of o and Fe, and B, Al, Si, Ga, Ge, Ti, and Z.
In a film composed of nitrogen and at least one element M ′ selected from the group X consisting of r, Hf, Nb, Ta, Mo and W, as shown in FIGS. The M'component concentration or the nitrogen concentration is higher toward the initial formation layer of the film, that is, toward the support substrate surface side, and the M'component concentration or the nitrogen concentration is relatively decreased in the film thickness (film thickness growth) direction. .. By selecting and setting such a configuration, deterioration of the soft magnetic properties in the initial growth layer of the alloy magnetic film, that is, in the vicinity of the supporting substrate surface is suppressed, and the saturation magnetic flux density of the finally formed alloy magnetic film is reduced. It is possible to minimize the decrease in Bs. As a result, for example, MI
Also when applied to the production of the G head, it is possible to reduce the generation of a pseudo gap between the support substrate and the alloy-based magnetic film, and thus to reduce the ripple of the frequency characteristic.

Further, in FIGS. 2A and 2B, the M'component concentration or the nitrogen concentration is lower in the initial formation layer of the film, that is, in the support substrate surface side, and in the film thickness (film thickness growth) direction. A configuration in which the concentration or the nitrogen concentration is relatively increased is shown.
By selecting and setting such a configuration, it is possible to suppress the increase of Hc due to the increase of crystal grains in the latter stage of the film growth, and to minimize the decrease of the saturation magnetic flux density Bs of the finally formed alloy magnetic film. It becomes possible to suppress.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

Example 1 Using a Co-11.5 at% Fe-4 at% A1 alloy target and a two-pole radio frequency (RF) magnetron sputtering apparatus in an Ar + N ₂ gas atmosphere while applying an appropriate bias voltage, a Si substrate was used. A film was formed on the above with the total sputtering gas pressure as a parameter. The sputtering conditions are as follows.

High frequency current density 7.4 W / cm ² Total sputter gas pressure 0.06 Pa to 0.2 Pa Nitrogen gas 20% Pre-evacuation 2 × 10 ⁻⁴ Pa or less Coercive force H of the alloy magnetic film obtained as described above
c was measured with a BH loop tracer with an applied magnetic field of 4000 A / m, and saturation magnetic flux density Bs was measured with VSM.

FIG. 3 shows the dependence of the coercive force Hc, the saturation magnetic flux density Bs and the Al concentration in the alloy magnetic film on the total sputtering gas pressure when the film thickness is 0.3 μm and when the film thickness is 4 μm. Show. However, the saturation magnetic flux density Bs and the Al concentration in the alloy magnetic film did not depend on the film thickness. As can be seen from FIG. 3, the coercive force Hc and the saturation magnetic flux density Bs when the film thickness was 0.3 μm decreased as the total sputtering gas pressure was increased, and at this time, the increase of the A1 concentration was observed. On the other hand, the coercive force Hc when the film thickness is 4 μm does not depend on the total sputter gas pressure and is as low as about 80 A / m.
showed that.

Therefore, in the initial stage of sputtering, the total sputtering gas pressure is set to 0.2 Pa, and the total sputtering gas pressure is set to 0.06 Pa at the end of the sputtering when the grown film thickness becomes 4 μm. Was changed and sputtering was performed. As a result, the magnetic properties of the grown alloy-based magnetic film as a whole were excellent, with a coercive force Hc of 100 A / m and a saturation magnetic flux density Bs of 1.75 T. Also,
The coercive force Hc at this time was as small as 200 A / m even when the film thickness was thin (<0.3 μm), and the film thickness dependence was small.

Example 2 A CoFe _11.5 A1 ₄ alloy target was used, and a two-pole RF sputtering apparatus different from the apparatus used in Example 1 was used to
Film formation was performed in a r + N ₂ gas atmosphere while applying an appropriate bias voltage, using the nitrogen partial pressure as a parameter on the Si substrate. The film thickness formed by this sputtering
When the thickness is 0.5 μm, the coercive force Hc, nitrogen concentration, and saturation magnetic flux density Bs of the alloy magnetic film when the film thickness is 4 μm
Fig. 4 shows the results of examining the nitrogen partial pressure dependence of the. However, the nitrogen concentration and the saturation magnetic flux density Bs in the alloy magnetic film did not depend on the film thickness. As can be seen from Fig. 4, the film thickness is 0.5
In the case of μm, the nitrogen concentration increased and the saturation magnetic flux density Bs decreased as the nitrogen partial pressure increased. The coercive force Hc showed the minimum value at a nitrogen partial pressure of 0.1 to 0.13 Pa. On the other hand, the film thickness is 4
When the thickness is set to 0.5 μm, it does not depend on the nitrogen partial pressure as in the case where the film thickness is 0.5 μm, and when the nitrogen partial pressure is 0.033 Pa, the film thickness is 0.5 μm.
The coercive force Hc at m was about 430 A / m, while the coercive force Hc was about 100 A / m.

Therefore, the nitrogen partial pressure in the initial stage of sputtering is
Sputtering was performed with the pressure set to 0.13 Pa, and the nitrogen partial pressure during sputtering was changed over time so that the nitrogen partial pressure was 0.033 Pa at the end of sputtering. The sputtering at this time was under the following conditions.

High-frequency current density 5.1 W / cm ² Total sputter gas pressure 1.3 Pa Nitrogen gas pressure 0.03 Pa to 0.25 Pa Pre-evacuation 1.3 × 10 ^-4 Pa or less The characteristics of the alloy-based magnetic film obtained as described above were evaluated. The magnetic characteristics seen as a whole are coercive force Hc ~ 90A /
m, and the saturation magnetic flux density Bs1.8 T showed good soft magnetism.
Further, the coercive force Hc at this time has a small film thickness (<0.5 μm
In this case, it was as small as 70 A / m and the film thickness dependence was small.

Example 3 Using a Co ₉₀ Fe ₁₀ alloy target and an A1 target, a binary simultaneous RF sputtering system was used for Ar + N ₂
While applying an appropriate bias voltage in a gas atmosphere, S
On the i substrate, the high frequency current density of the Co ₉₀ Fe ₁₀ target was kept constant at 7.4 W / cm ^2, and the high frequency current density of the A1 target was set to 3.1 W / cm ² at the beginning of film formation, and 1.8 W at the end of film formation. / cm ² and comprising reducing the introduced high frequency current density in accordance with the time of film formation as a high A1 concentration in the film in the film formation initial, so that A1 concentration in the film formation at the time of film formation completion lowered, simultaneously Sputtering was performed. The sputtering conditions at this time are as follows.

High frequency current density Co ₉₀ Fe ₁₀ 3.7 W / cm ² Al 1.8 W / cm ² to 3.1 W / cm ² Total sputter gas pressure 1.3 Pa Nitrogen gas pressure 0.26 Pa Pre-evacuation 1.3 × 10 ^-4 Pa or less Obtained by the above When the characteristics of the alloy-based magnetic film were evaluated, the magnetic properties of the entire film were found to be coercive force Hc to 70 A /
m, and the saturation magnetic flux density Bs was 1.8 A / m. Further, the coercive force Hc at this time was as small as 60 A / m even when the film thickness was thin (<0.2 μm), and the film thickness dependence was small.

Example 4 4 at.%, 6 at.% Or 8 at.% Al in the target composition
CoFe _11.5 Al ₄ alloy target, CoFe ₁₁
Using three types of targets, an Al ₆ alloy target and a CoFe ₁₁ Al ₈ alloy target, with a three-way RF sputtering apparatus in an Ar + N ₂ gas atmosphere while applying an appropriate bias voltage, as shown in a sectional view in FIG. CoFe ₁₀
Al _3.5 / CoFe ₁₀ Al _5.1 / CoFe ₁₀ Al _7.2 /
A laminated magnetic film composed of a supporting substrate was produced. In FIG. 5, 1 is a support substrate, 2 is an alloy-based magnetic film formed by targeting a CoFe ₁₁ Al ₈ alloy, and 3 is CoFe ₁₁ A.
Alloy-based magnetic film formed by using ₁₆ alloy as a target, 4
Is an alloy-based magnetic film formed by using a CoFe _11.5 Al ₄ alloy as a target.

The alloy-based magnetic film (total film thickness 3
The magnetic properties of the film as a whole were as follows: coercive force Hc to 80 A / m, saturation magnetic flux density Bs to 1.
Good characteristics of 7 T were exhibited. In addition, this laminated film is heat-treated to reduce the film thickness to 0.5 without deterioration of characteristics.
Even when it was as thin as μm or less, Hc was as small as 80 A / m, and the coercive force Hc also had a small film thickness dependency.

As a comparative example, the effect of the third element in the CoFe alloy will be shown.

A CoFe _11.5 Al ₄ alloy target or a CoFe ₁₁ Al ₈ alloy target was used and a two-pole RF sputtering apparatus was used in an Ar + N ₂ gas atmosphere while applying an appropriate bias voltage, with the film thickness on the Si substrate as a parameter. The alloy magnetic film was formed under the following conditions.

High frequency current density 3.7 W / cm ² Total sputter gas pressure 1.3 Pa Nitrogen gas pressure 0.26 Pa Pre-evacuation 1.3 × 10 ^-4 Pa or less Next, an alloy magnetic film produced using a CoFe _11.5 Al ₄ alloy target was prepared. FIG. 6 shows the result of measuring the frequency characteristic of the output by using the MIG head manufactured by the conventional means.
Shown in. As can be seen from FIG. 6, waviness of 3 to 4 dB or more occurred and it was impossible to use as a head. In order to investigate the cause of this waviness, the results of measuring the film thickness dependence of the coercive force Hc are shown in FIG. As can be seen from FIG. 7, CoFe _11.5
When an Al ₄ alloy target is used, the coercive force Hc increases as the formed magnetic film thickness decreases. That is, magnetic property deterioration was recognized in the initial stage of film growth. The waviness shown in FIG. 6 is generated in the MIG head having the above-described structure because the magnetic characteristic deterioration of the magnetic film at the initial stage of film growth is
It is considered that there is a pseudo gap between the support substrate and the magnetic film.

On the other hand, Co whose Al addition amount is increased to 8%
For a magnetic film formed by sputtering using an Fe ₁₁ Al ₈ alloy target, coercive force Hc and saturation magnetic flux density B
The result of having measured the film thickness dependence of s is shown in FIG. For reference, the film thickness dependence of the saturation magnetic flux density Bs when a CoFe _11.5 Al ₄ alloy target is used is also shown. As can be seen from FIG. 8, when the Fe ₁₁ Al ₈ alloy target was used, the alloy magnetic film formed showed a low coercive force Hc independent of the film thickness. However, the saturation magnetic flux density Bs was lower than that using the CoFe _11.5 Al ₄ alloy target and was about 1.5 T, which was almost the same as the saturation magnetic flux density Bs of the conventional alloy magnetic film.

Example 5 Using a Co-11.5 at% Fe-5 at% Ta alloy target and a bipolar radio frequency (RF) magnetron sputtering apparatus in an Ar + N ₂ gas atmosphere while applying an appropriate bias voltage, a Si substrate was used. A film was formed on the substrate using the substrate temperature as a parameter. The sputtering conditions are as follows.

High frequency current density 7.4 W / cm ² Total sputter gas pressure 0.2 Pa Nitrogen gas 10% Pre-evacuation 2 × 10 ⁻⁴ Pa or less For the alloy magnetic film obtained as described above, the substrate temperature and coercive force during film formation When the relationship of Hc was examined, it was as shown in FIG. As can be seen from FIG. 9, the alloy magnetic film formed at a low substrate temperature of about 50 ° C. showed a low coercive force Hc of 40 A / m or less, but was formed as the substrate temperature was increased. The coercive force Hc of the alloy magnetic film is increasing.
The reason for this is that the alloy-based magnetic film formed at a low substrate temperature is
The crystal grains are miniaturized, and the coercive force Hc becomes low due to the miniaturization of the crystal grains. On the other hand, in the alloy-based magnetic film formed at the high substrate temperature, the crystal grains grow and the coercive force is grown by the growth of the crystal grains. It is considered that Hc increases. That is, for example, in the process of forming a magnetic film (usually a film thickness of several μm) used as a magnetic head for a VTR, the substrate temperature is low in the initial stage of film formation, but the substrate temperature rises as the film formation progresses. .. Therefore, it can be said that the crystal grains are more likely to become finer in the initial stage of film formation, and crystal growth occurs in the latter stage of film formation.

The additive element Ta in the above has an effect of refining the crystal grains of the magnetic film to be formed, but has a concentration enough to suppress the crystal grain growth in the latter stage of film formation where the substrate temperature rises. When Ta is added, the saturation magnetic flux density Bs of the formed magnetic film as a whole is significantly reduced. Therefore, the following three types of targets were used to form a film in which the Ta concentration was increased in the latter stage of film formation as compared with the initial stage of film formation.

That is, Ta is 5 at.
%, 7 at.% Or 9 at.% CoFe _11.5 Ta ₅ alloy target, CoFe ₁₁ Ta ₇ alloy target, Co
Using three types of targets, Fe ₁₁ Ta ₉ alloy targets, and a three-way RF sputtering apparatus in an Ar + N ₂ gas atmosphere while applying an appropriate bias voltage, CoFe ₁₀ Ta ₈ / CoFe ₁₀ Ta ₆ /
A laminated magnetic film composed of CoFe ₁₀ Ta ₅ / support substrate was produced. In FIG. 10, 1 is a support substrate, 2'is Co
Alloy-based magnetic film formed by using Fe _11.5 Ta ₅ alloy as a target, 3 ′ is an alloy-based magnetic film formed by using CoFe ₁₁ Ta ₇ alloy as a target, and 4 ′ is an alloy-based magnetic film formed by using CoFe ₁₁ Ta ₉ alloy as a target. Is.

The alloy magnetic film (total film thickness 4
The magnetic properties of the film as a whole were coercive force Hc to 40 A / m and saturation magnetic flux density Bs to 1.
It showed a good characteristic of 6 T. In addition, this laminated film is heat-treated to reduce the film thickness to 0.5 without deterioration of characteristics.
The coercive force Hc was as small as 55 A / m even when it was as thin as μm or less, and the film thickness dependence of the coercive force Hc was also small.

As a means for giving a Ta concentration gradient to the magnetic film to be formed, as described above, a method of performing sputtering using a target having a higher Ta concentration in the latter stage of sputtering than in the initial stage of sputtering, for example, all sputtering gas is used. The sputtering conditions such as pressure and nitrogen partial pressure may be changed intermittently or continuously in the early and late stages of sputtering, and the sputtering may be performed under the condition that the Ta concentration increases in the latter stage of film growth compared to the earlier stage of film growth.

Next, as an application example of the alloy-based magnetic film according to the present invention, the case of being applied to the structure of a magnetic head will be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 11 is a cross-sectional view showing an example of the essential structure of a thin-film magnetic head used for recording / reproducing with respect to a longitudinal recording hard disk. Reference numeral 5a denotes the above-mentioned present invention which is adhered and formed on a supporting substrate 6. The ferromagnetic film 7 is a first insulating layer laminated on the ferromagnetic film 5a so as to form a predetermined gap 8 at the head tip side. Further, 9 is a coil wound on the first insulating layer 7, and 10 is a second insulating layer adhered to cover the coil 9. Then, the ferromagnetic film 5b according to the present invention is partly in contact with the ferromagnetic film 5a on the surface of the second insulating layer 10 in the previous period, and a gap 8 is formed between the ferromagnetic film 5b and the ferromagnetic film 5a on the head tip side. And a protective film 12 is formed on the ferromagnetic film 5b.

The ferromagnetic films (alloy-based magnetic films) 5a, 5b according to the present invention have a higher saturation magnetic flux density than conventional ferromagnetic films (NiFe film, Co-based amorphous film, etc.), and are suitable for high coercive force media. On the other hand, sufficient recording is possible, and since there is no magnetic deterioration in the initial layer of film growth, the target gap length can be reliably obtained, and as a result, high density recording is possible.

FIG. 12 is a perspective view showing an example of the essential structure of a metal in-gap head. 13a and 13b are a pair of ferrite cores, and 16a and 16b are intermediate faces of the ferrite cores 13a and 13b facing each other. The alloy-based magnetic film according to the present invention is disposed via layers 14a and 14b. Intermediate layer in this configuration
14a and 14b are for strengthening adhesion and ferrite cores 13a and 13b.
It plays the role of preventing mutual diffusion between b and the ferromagnetic films 16a and 16b, and is preferably composed of Cr, SiO ₂ , NiFe or the like. Further, 15 is welded so as to form a required gap 8 between the alloy-based magnetic films 16a and 16b arranged on the facing surfaces of the ferrite cores 13a and 13b with the intermediate layers 14a and 14b interposed therebetween. Glass, 9 is the ferrite core 13a
The coil is wound around.

In this structure, since the ferromagnetic films 16a and 16b have no magnetic deterioration in the initial layer of film growth, a pseudo gap is generated between the ferrite cores 13a and 13b and the ferromagnetic films 16a and 16b. When used as a head, the output frequency characteristic does not swell, and the saturation magnetic flux density is higher than that of a conventional ferromagnetic film (such as a Co-based amorphous film). It is possible to record enough even for.

In the above examples, the case where the concentration distribution of the M'component or nitrogen N in the alloy type magnetic film, that is, the compositional change in the film thickness direction is continuous, is shown, for example, in FIG.
As shown by the dotted line in (b) and FIGS. 2 (a) and 2 (b), the same effect can be expected even if the composition change in the film thickness direction is discontinuous. That is, M ′ between one main surface side and the other main surface side
It suffices that the concentration distribution of the component or nitrogen N holds the relation between the relatively high concentration and the low concentration.

Further, the same applies when M'component Al in the alloy type magnetic film in the above embodiment is replaced by Ga or In, for example, or when Ta is replaced by Ti, Zn, Hf, Nb, Mo or W. The result was confirmed.

[0040]

As described above in detail, in the alloy type magnetic film (magnetic member) according to the present invention, the magnetic characteristics of the film are averaged while maintaining a high saturation magnetic flux density Bs. as a result,
When the alloy-based magnetic film according to the present invention is used, for example, in the construction of a magnetic head, it functions as a magnetic head having excellent recording ability and reproducing ability because there is no pseudo gap.

[Brief description of drawings]

FIG. 1 (a) is a diagram showing a change in M ′ (X) concentration of a magnetic film according to the present invention with respect to a distance from a support substrate surface, and (b) is a diagram showing nitrogen concentration support of a ferromagnetic film according to the present invention. The figure showing the change with respect to the distance from the substrate surface.

FIG. 2 (a) is a diagram showing a change in M ′ (X) concentration of a magnetic film according to the present invention with respect to a distance from a surface of a supporting substrate, and (b) is a diagram showing nitrogen concentration support of a ferromagnetic film according to the present invention. The figure showing the change with respect to the distance from the substrate surface.

FIG. 3 is a graph showing CoFe in forming a magnetic film according to the present invention.
_11.5 A characteristic diagram showing the dependency of coercive force Hc, saturation magnetic flux density Bs, and Al concentration on the total sputtering gas pressure when a film is formed using Al ₄ as a target.

FIG. 4 is a graph showing CoFe in forming a magnetic film according to the present invention.
_11.5 A characteristic diagram showing the dependency of coercive force Hc, saturation magnetic flux density Bs, and Al concentration on the total sputtering gas pressure when a film is formed using Al ₄ as a target.

FIG. 5 is a sectional view showing a structural example of a magnetic film according to the present invention.

FIG. 6 is a characteristic diagram showing an output frequency characteristic in a metal-in-gap type head configured by using a magnetic film whose film initial growth layer is magnetically deteriorated.

FIG. 7 is a characteristic diagram showing film thickness dependence of coercive force Hc when a film is formed using CoFe _11.5 Al ₄ as a target in forming a magnetic film.

FIG. 8 is a characteristic diagram showing the film thickness dependence of coercive force Hc and saturation magnetic flux density Bs when a film is formed using CoFe _11.5 Al ₈ or CoFe _11.5 Al ₄ as a target in the formation of a magnetic film.

FIG. 9 is a characteristic diagram showing the substrate temperature dependence of the coercive force Hc when CoFe _11.5 Ta ₅ is used as a target in the formation of a magnetic film.

FIG. 10 is a sectional view showing another structural example of the magnetic film according to the present invention.

FIG. 11 is a sectional view showing a main part of a thin film magnetic head for longitudinal recording, which is formed by using a magnetic film according to the present invention.

FIG. 12 is a perspective view showing a main part of a metal in-gap head configured by using a ferromagnetic film according to the present invention.

[Explanation of symbols]

1, 6 ... Support substrate 2 ... CoFe ₁₁ Al ₈ magnetic film formed by sputtering target 2 ′ ... CoFe
_11.5 Magnetic film formed by sputtering Ta ₅ target
3 ... Magnetic film formed by sputtering CoFe ₁₁ Al ₆ target 3 '... Magnetic film formed by sputtering CoFe ₁₁ Ta ₇ target 4 ... CoFe _11.5 Al ₄ Magnetic film formed by sputtering target 4' ... CoFe ₁₁ Ta ₉
Magnetic film formed by sputtering target 5, 11,
16a, 16b ... Magnetic film (ferromagnetic film) 7 ... First insulating layer (film) 8 ... Gap 9 ... Coil 10 ... Second insulating layer (film) 12 ... Protective layer (film) 13a, 13b ... Ferrite core 14a, 14b ... Intermediate layer 15 ... Glass layer

Claims (1)

1. A general formula, MM'N (wherein M is at least one of Co and Fe).
Species of transition metals, M'is B, Al, Si, Ga, Ge, T
i, Zr, Hf, Nb, Ta, Mo, W, N is nitrogen, and the alloy-based magnetic film is M ′ or M ′ in the alloy-based magnetic film. A magnetic member having a relatively high concentration of N on one main surface side.