JP3404054B2 - Thin film for magnetic head and magnetic head - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soft magnetic thin film and a magnetic head, particularly a metal-in-gap (MIG) type magnetic head, an enhanced dual gap length (EDG) type magnetic head, and a thin film magnetic head. Regarding

[0002]

2. Description of the Related Art A MIG type magnetic head having a soft magnetic thin film such as sendust having a saturation magnetic flux density Bs higher than that of a core is known on at least one gap facing surface of a first core and a second core made of ferrite. Has been. In this magnetic head, a strong magnetic flux can be applied to the magnetic recording medium from the soft magnetic thin film, so that effective recording can be performed on the medium having a high coercive force.

Further, a flying type thin film magnetic head having excellent characteristics such as high density recording and high speed data transfer has been put into practical use.

In order to generate a high density magnetic flux even in the thin film magnetic head, soft magnetic thin films such as Permalloy and Sendust having a high saturation magnetic flux density Bs are used for the upper and lower magnetic pole layers.

By the way, the saturation magnetic flux density Bs of such a soft magnetic thin film used for a magnetic head is at most 12000.
It is about G. For this reason, the conventional magnetic head has insufficient electromagnetic conversion characteristics such as overwrite characteristics, and in particular, in the case of a magnetic recording medium having a high coercive force, a higher saturation magnetic flux density Bs is required.

It is known that Fe-based soft magnetic thin films having a strong (100) orientation have excellent soft magnetic properties because they have a small crystal magnetic anisotropy. However, even if the Fe-based soft magnetic thin film is formed by a general vapor phase method such as sputtering, the (100) orientation cannot be strengthened, and mainly (11)
0) A plane-oriented or non-oriented thin film is formed. Therefore, (10
0) In order to form a film having a strong orientation, a substrate made of a specific material, such as ZnSe, or a single crystal substrate of (100) orientation or GaAs having a strong (100) orientation must be used. I won't.

A film having such a strong (100) orientation is
Since it is realized only under limited conditions, it is very difficult to increase the (100) orientation or the (100) orientation of the soft magnetic thin film of the magnetic head.

By the way, targeting Fe, Ar and N
_By sputtering in a mixed gas of _2, an Fe-N soft magnetic thin film having a higher saturation magnetic flux density Bs than Sendust can be obtained. This is done by mixing N
This is because the Fe crystal grains are made finer and the magnetic anisotropy dispersion is reduced.

For example, in Japanese Patent Laid-Open No. 64-15907, Fe is the main component, and Fe ₄ N and / or Fe ₃ N are used.
A soft magnetic thin film containing iron nitride is disclosed. The soft magnetic thin film has a saturation magnetic flux density of 150.
It has a magnetic coercive force Hc of less than 00 G and a magnetic property suitable for the magnetic head.

However, the Fe-N soft magnetic thin film has low heat resistance, the crystal grain size becomes large at a temperature of about 350 ° C., and the coercive force Hc sharply increases.

Therefore, the heat treatment such as glass welding causes
It is difficult to use for a MIG type magnetic head or an EDG type magnetic head which is kept at a temperature of about 50 to 700 ° C., and a thin film magnetic head which is kept at a temperature of about 350 ° C. or higher in a film forming process such as sputtering. Is. in addition,
This soft magnetic thin film cannot have a strong (100) orientation only by forming a film on an ordinary substrate by a vapor phase method such as sputtering.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thin film for a magnetic head having high heat resistance and corrosion resistance, a high saturation magnetic flux density Bs, and excellent soft magnetic characteristics, and a thin film having such a thin film. An object is to provide an MIG type magnetic head, an EDG type magnetic head, and a thin film magnetic head.

[0013]

Means for Solving the Problems] The above object, the present
It is achieved by the inventions of claims 1 to 6 .

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

The soft magnetic thin film for the magnetic head of the present invention is made of Fe-
Since it is N type, the saturation magnetic flux density Bs is very high and the coercive force Hc is low.

Further, the micro Vickers hardness is high, which is advantageous in terms of wear resistance.

Then, a predetermined element is added to Fe and N at a predetermined amount ratio (y / x) and deposited, and then heat-treated to form (100) plane orientation or orientation on the core or slider. A soft magnetic thin film with high strength can be formed. Therefore, the soft magnetic characteristics are remarkably improved.

In addition, since this additive element forms a nitride more stable than Fe, the saturation magnetic flux density Bs is preferably maintained at about 14000 G or more, particularly 16000 G or more, and the heat resistance and the corrosion resistance are remarkably improved. .

Assuming that the temperature at which the coercive force abruptly changes by heat treatment, for example, the heat treatment temperature at which the coercive force Hc becomes 2 Oe is the heat resistant temperature, the soft magnetic thin film used in the present invention has a heat resistant temperature of about 500 ° C. In particular, the temperature is 550 ° C or higher, and further 600 ° C or higher.

In this case, European Patent Publication No. 380136 discloses that an amorphous Fe-MN system thin film is deposited and then heat-treated to form a (110) plane oriented film. . However, the amorphous film immediately after the deposition does not exhibit the soft magnetic property, but exhibits the soft magnetic property only after the (110) orientation is given.

On the other hand, in the present invention, the (100) plane orientation is provided immediately after the deposition, so that the soft magnetic characteristics sufficient for practical use are exhibited. The degree of (100) plane orientation is further increased by the heat treatment, so that the soft magnetic characteristics are further improved. At this time, the dependence of the characteristics on the heat treatment conditions is reduced, and the heat treatment conditions can be easily controlled. In addition, heat resistance is improved, and heat treatment can be performed at 600 ° C. or higher, further 700 ° C. or higher, and glass fusion during head assembly is facilitated.

Therefore, the soft magnetic thin film of the present invention has a high saturation magnetic flux density Bs, a low coercive force Hc, and a magnetic permeability μ.
Has excellent soft magnetic properties. And the magnetostriction is also small.

Therefore, the magnetic head of the present invention having such a soft magnetic thin film has high overwrite characteristics, high recording / reproducing sensitivity, etc., and excellent electromagnetic conversion characteristics.

In addition, since the soft magnetic thin film of the present invention is excellent in corrosion resistance and wear resistance, a highly reliable magnetic head can be realized.

In JP-A-60-218820 and JP-A-60-220913, Fe, 2-10 wt% of Al, 3-16 wt% of Si, and 0.005-
A magnetic thin film containing 4 wt% nitrogen is disclosed. Then, it is described that the saturation magnetic flux density Bs can be improved by substituting a part of Fe with Co, and the magnetic permeability μ can be maintained at a high level without reducing Bs by substituting with Ni. .

However, the specific examples shown in the examples have a high heat resistance temperature, but the saturation magnetic flux density Bs is about 12000 G at most.

Thus, a soft magnetic thin film having a high saturation magnetic flux density Bs, a low coercive force Hc, a high magnetic permeability μ and an excellent heat resistance is not known.

[0035]

Specific Structure The specific structure of the present invention will be described in detail below.

The soft magnetic thin film of the present invention, which is particularly suitable for a magnetic head, is deposited on a core or slider with an atomic ratio composition represented by the following formula.

Formula (Fe _100-Z Ni _z ) _100-xy M _x N _y

In the above equation, M is Mg, Ca, Ti, Z.
It is one or more selected from r, Hf, V, Nb, Ta, Cr, Mo, W, Mn and B.

For elements other than the above, such as Ru, the saturation magnetic flux density also lowers Bs and soft magnetic characteristics.

Of these, Zr alone or V alone, especially Z in order to enhance the (100) plane orientation, is preferred.
r alone or Zr and / or V is 20 in M
% Or more, and a combination with any of the above elements other than Zr and V is preferable.

Further, x is 6.5 to 14, more preferably 7 to 12. If it is less than the above range, the heat resistance is insufficient. Therefore, the coercive force Hc tends to increase significantly due to heat treatment or the like. Beyond the above range, the saturation magnetic flux density B
s decreases. Therefore, when applied to a magnetic head, the overwrite characteristic tends to deteriorate. Further, in the range other than this, the hardness decreases and the magnetostriction increases. And
In such a range, a soft magnetic thin film having a (100) orientation or a strong degree of orientation is easily obtained, and the soft magnetic characteristics are remarkably improved. In addition, heat resistance is improved, and Hc is 2 Oe or more, especially 1
The heat resistant temperature of Oe or higher reaches 700 ° C., and particularly reaches 750 ° C. or higher.

Y is 6.5 to 15, more preferably 7-1.
It is 2. If it is less than this range, the crystal grains are not sufficiently refined by N, and soft magnetic properties tend not to be obtained. If the amount exceeds the above range, nitrides of Fe, Ni, and M are generated more than necessary, and soft magnetic characteristics cannot be obtained. And, in such a range, the (100) plane orientation becomes more preferable.

If necessary, in addition to nitrogen, oxygen may be contained at 5 at% or less of the whole.

And, y / x is 0.7 to 1.5, more preferably 0.8 to 1.2. This gives (10
0) An alignment film can be easily obtained.

Z is 0 to 10, preferably 0 to 5.
The magnetic permeability μ can be improved by adding Ni. However, if it exceeds the above range, the saturation magnetic flux density Bs
Tends to decrease. When Ni is contained as an essential component, the content z thereof is preferably 1 to 10, more preferably 1 to 5.

The composition of the soft magnetic thin film of the present invention as deposited is determined by, for example, Electron Probe Micro Analysis (EPM
It may be measured by the A) method.

The thickness of the soft magnetic thin film may be appropriately selected according to the application etc., but is usually about 0.1 to 10 μm.

To form the soft magnetic thin film of the present invention, various vapor phase methods such as vapor deposition, sputtering, ion plating and CVD may be used.

Of these, it is particularly preferable to form the film by the sputtering method, and for example, the film may be formed as follows. As the target, an alloy cast body, a sintered body, a multi-source target, or the like is used. Then, sputtering is performed in an atmosphere of an inert gas such as Ar.

When reactive sputtering is performed,
The composition of the target may be substantially the same as the one not containing N in the above formula. Then, the sputtering is carried out in an atmosphere containing 0.1 to 15% by volume, preferably 2 to 10% by volume of N ₂ in Ar. If it is out of the above range, soft magnetic properties tend not to be obtained.

The sputtering method is not particularly limited, and the sputtering apparatus to be used is also not limited, and a normal one may be used. The operating pressure is usually 0.1 to 1.0.
It should be about Pa. In this case, various conditions such as sputtering input voltage and current are appropriately determined according to the sputtering method and the like. However, in order to enhance the (100) orientation, the leakage magnetic field of 100 to
It is preferable to use magnetron sputtering performed under the condition of about 500 Oe. The magnetron sputtering may be performed at high frequency or direct current.

The film immediately after film formation itself has a (100) orientation, but it is preferable that the film after deposition is subjected to heat treatment on the soft magnetic thin film. By heat treatment, (100)
The orientation or the degree of orientation becomes stronger, the soft magnetic characteristics are remarkably improved, and the saturation magnetic flux density Bs is also improved.

Specifically, the film is (100) before the heat treatment.
It has orientation, and the (200) plane is oriented parallel to the film surface (substrate surface). The X-ray diffraction chart shows Fe (20)
0) peak is present, but heat treatment causes Fe (110)
The relative intensity ratio of the Fe (200) peak to the peak is
2 or more by increasing the heat treatment temperature from 1 or more,
Further, it increases to 3 or more, and infinitely in some cases, and further, the saturation magnetic flux density Bs also improves.

In this case, for example, a soft magnetic thin film having a strong (100) orientation can be realized by forming a film on any substrate such as a magnetic substance such as ferrite, a non-magnetic ceramics, a polymer film or the like.

This means that the (100) plane orientation can be confirmed because the diffraction ring from the Fe (200) plane is discontinuous in the electron beam diffraction pattern.

In the present invention, in the X-ray diffraction chart of the film,
The relative intensity ratio of the Fe (200) peak to the Fe (110) peak is 1 or more, and the (100) orientation is increased as compared with the non-oriented state. In particular, this value is 2 or more, and more preferably 3 or more. preferable. The 2θ (θ is the diffraction angle) of the Fe (110) peak in the X-ray diffraction chart is about 44.7 degrees when CuKα is used, and
The 2θ of the (200) peak is about 65 degrees.

As the heat treatment conditions, the following conditions are particularly preferable. Temperature rising rate: about 2 to 8 ° C./min Holding temperature: 200 to 800 ° C., particularly about 400 to 750 ° C., further about 400 to 700 ° C., especially 550 ° C. or more, further 580 ° C. or more, (100) plane orientation Is improved,
Stable enough at 600 ° C or higher, especially 750 ° C or higher Holding time: about 10 to 60 minutes Cooling rate: about 2 to 8 ° C / minute

The atmosphere may be an inert gas such as Ar. By performing the heat treatment under the above conditions, a soft magnetic thin film having more excellent soft magnetic characteristics can be obtained.

By such heat treatment, N ₂ is released from the film, and in the above composition formula, 6.5 ≦ x ≦ 14,
6.2 ≦ y ≦ 15, 0.68 ≦ y / x ≦ 1.5, 0 ≦ z
The film is about ≦ 10. Thus, the composition of the present invention is
Little change in composition after heat treatment. Also, as described above, y
Since / x is in the vicinity of 1, the orientation degree of (100) orientation is improved after the heat treatment. This is because ZrN serves as an inhibitor during the growth process of Fe crystallinity, so that (100) orientation is preferentially performed, and y / x of the film immediately after film formation is increased.
Must be close to 1. In addition, since the generation of ZrN suppresses the growth of Fe crystal grains, the thermal stability is improved,
Maintains high magnetic permeability up to high temperature.

The soft magnetic thin film of the present invention has, for example, a film thickness of 1 to 5
When it is about μm, it has the following characteristics.

Coercive force Hc (50 Hz): about 0.1 to 2 Oe, particularly 0.
1 to 1 Oe Initial permeability μ _i (5 MHz): 1000 to 5000, particularly 2000 to 5000 Saturation magnetic flux density Bs (DC): 13000 to 20000 G
Depending on the heat treatment, about 1400 to 20,000G, about 16000 to 20,000G, especially 17,000 to 1
Improved to about 9000 G Magnetostriction: about −2 × 10 ⁻⁶ to + 2 × 10 ⁻⁶ Average grain size D: about 50 to 500 A, especially 1
About 00-300A, further about 150-250A Micro Vickers hardness: 700 or more, by heat treatment,
Improve to 1100 or more, especially 1150 or more, generally 1500 or less

For the measurement of the magnetic characteristics of the soft magnetic thin film, for example, when applied to a magnetic head, a thin film was formed on a non-magnetic substrate under the same conditions as those for forming a magnetic head, and heat treatment was performed under the same conditions. After that, it may be performed as follows.

Initial permeability (μ _i ): Using an 8-shaped coil permeability measuring device, measured with an applied magnetic field of 5 mOe Coercive force (Hc): measured with BH tracer Saturated magnetic flux density (Bs): VSM Used, measured in a magnetic field of 10000 G Magnetostriction: measured with an applied magnetic field of 100 Oe by the optical lever method

The average crystal grain size D of the crystal grains can be obtained from the Scherrer's formula below by measuring the half width W ₅₀ of the Fe (200) peak of the X-ray diffraction line. Formula D = 0.9λ / W ₅₀ cos θ

In the above equation, λ is the wavelength of the X-ray used, and θ is the diffraction angle. As described above, when CuKα is used, the 2θ of the Fe (200) peak is about 65 degrees. Furthermore, the micro Vickers hardness is JIS
It may be measured according to.

Such a soft magnetic thin film of the present invention is particularly suitable for M
It can be applied to various magnetic heads such as an IG (metal-in-gap) type magnetic head and a thin film magnetic head. In addition to the magnetic head, it can be applied to various soft magnetic parts such as a thin film inductor.

Next, the magnetic head of the present invention will be described. A preferred embodiment of the MIG type magnetic head of the present invention is shown in FIG.
And shown in FIG.

The magnetic head shown in FIG. 1 has the first core 1
And a second core 2 having a soft magnetic thin film 4 formed on the trading side of the surface facing the gap, and the two cores are joined together with a winding window 8 through a gap 5.
It is fused and integrated by the fused glass 3.

The magnetic head shown in FIG. 2 is of a type in which the soft magnetic thin film 4 is formed on the surfaces of the first core 1 and the second core 2 which face the gap portions.

In the present invention, the cores 1 and 2 are preferably made of ferrite. In this case, the ferrite used is not particularly limited, but Mn-Zn ferrite or Ni-Zn ferrite is preferably used according to the purpose.

Fe ₂ O as Mn--Zn ferrite
₃ 50-60 mol%, ZnO 8-25 mol%,
It is preferable that the balance is substantially MnO. In addition, Ni
-Zn ferrite exhibits excellent characteristics especially in a high frequency region, and a preferable composition is Fe ₂ O ₃
Is 30 to 60 mol%, NiO is 15 to 50 mol%, Zn
O is about 5 to 40 mol%.

DC saturation magnetic flux density Bs of cores 1 and 2
Is preferably 3,000 to 6,000 G. When the saturation magnetic flux density is less than the above range, the overwrite characteristic is deteriorated, and in such a composition of the saturation magnetic flux density, the Curie temperature is lowered and the thermal stability is deteriorated. If it exceeds the above range, magnetostriction is increased and the characteristics of the magnetic head are deteriorated, or the magnetic head is easily magnetized.

The initial magnetic permeability μ _i of the cores 1 and 2 at DC is 1,
000 or more, and the coercive force Hc is preferably 0.3 Oe or less.

The surfaces of the cores 1 and 2 facing the gap are:
It is preferable that the surface is smoothed by mirror polishing or the like so that the soft magnetic thin film 4 and the base film described later can be easily formed.

The soft magnetic thin film 4 is provided in order to generate a magnetic flux having a high density at the time of recording and perform effective recording on a magnetic recording medium having a high coercive force. As the soft magnetic thin film 4, the above-mentioned soft magnetic thin film of the present invention is used.

The saturation magnetic flux density Bs of the soft magnetic thin film 4 when the magnetic head is completed is 14000 G or more, more preferably 16
It is preferably 000 G or more, particularly preferably 17,000 G or more. When it is less than the above range, the overwrite characteristic is deteriorated, and it is particularly difficult to record on a magnetic recording medium having a high coercive force.

The soft magnetic thin film 4 has a strong (100) orientation. When the (100) orientation is strong, the soft magnetic characteristics of the soft magnetic thin film 4 are improved and high recording / reproducing sensitivity is obtained.

The average crystal grain size of the crystal grains of the soft magnetic thin film 4 is preferably 500 A or less, more preferably 300 A or less, and especially about 100 to 300 A. In the above range, the soft magnetic characteristics are improved and high recording / reproducing sensitivity is obtained.

In this case, the soft magnetic characteristics, that is, the coercive force H of the soft magnetic thin film 4 at the completion of the magnetic head at 50 Hz.
c is preferably 2 Oe or less, and more preferably 1 Oe or less. The initial magnetic permeability μ _i at 5 MHz of the soft magnetic thin film 4 is preferably 1000 or more, and particularly 1500 or more. If the coercive force Hc exceeds the above range or if the initial magnetic permeability μ _i is less than the above range, the recording / reproducing sensitivity tends to decrease.

The thickness of the soft magnetic thin film 4 is preferably 0.2.
.About.5 .mu.m, more preferably 0.5 to 3 .mu.m. If the film thickness is less than the above range, the volume of the soft magnetic thin film 4 as a whole becomes insufficient, and the soft magnetic thin film 4 is likely to be saturated, and it becomes difficult to sufficiently fulfill the function of the MIG type magnetic head. Further, if it exceeds the above range, eddy current loss increases.

By having such a soft magnetic thin film 4, the magnetic head of the present invention can perform effective recording on a magnetic recording medium having a coercive force of 800 Oe or more.

If the core 1, the core 2 and the soft magnetic thin film 4 have the above-mentioned magnetic characteristics, a high output and resolution can be obtained as a magnetic head. Also, a good overwrite characteristic of -35 dB or less is obtained. In addition,
The resolution is, for example, (V _2f / V _1f ) × 100, when the output of the 1f signal is V _1f and the output of the 2f signal is V _2f.
It is represented by [%]. The overwrite characteristic is, for example, the 1f signal output with respect to the 2f signal output when the 2f signal is overwritten on the 1f signal.

The gap 5 is made of a non-magnetic material. In particular, it is preferable to use adhesive glass in the gap 5 in order to increase the adhesive strength.
The glass shown in No. 1506 and the like is suitable. Further, although the gap 5 may be formed of only the adhesive glass, it is preferable that the gap 5 is formed of two layers of the gap 51 and the gap 53 as shown in the figure in order to increase the gap forming speed and the gap strength. In this case, the gap 51 has an S
It is preferable to use iO ₂ and adhesive glass for the gap 53.

In the case of a magnetic head in which the fused glass 3 described later flows into both sides of the gap, the gap 5 may be formed of silicon oxide only. Gap 5
There is no particular limitation on the method of forming the above, but it is preferable to use the sputtering method. Gap length is usually 0.2-2.0μ
It is about m.

As shown in FIGS. 1 and 2, the MIG type magnetic head of the present invention is such that the first core 1 and the second core 2 are joined and integrated via the gap 5. The cores are usually joined by thermocompression bonding with the adhesive glass in the gap 53 and at the same time pouring the fused glass 3. The working temperature Tw of the welding glass 3 used is 450 to 75.
0 ° C, more preferably 450 to 700 ° C, especially 460 to
It is preferably about 650 ° C. As is well known, the working temperature Tw means that the viscosity of glass is 10 ⁴ poise.
Is the temperature at which

In the present invention, since the soft magnetic thin film 4 having high heat resistance is used, the coercive force Hc maintains a value of 2 Oe or less, particularly 1 Oe or less even when the Tw glass is used for welding. To do. The fused glass 3 is not particularly limited, but lead silicate glass is preferably used. Among these, for example, the glasses shown below are suitable.

PbO: about 67.5 to 87.5% by weight B ₂ O ₃ : about 4.0 to 8.1% by weight SiO ₂ : about 7.5 to 16.6% by weight Al ₂ O ₃ : 0. 3 to 0.8% by weight ZnO: 2.2 to 3.3% by weight Bi ₂ O ₃ : 0 to 0.1% by weight Na ₂ O, K ₂ O, CaO, etc .: 0 to 4% by weight sb ₂ O _3: about 0-1 wt%

The welding is carried out by the usual method with the welding temperature near the working temperature Tw. In this case, the welding process may double as the heat treatment of the soft magnetic thin film 4.

Further, in the present invention, as shown in FIG. 3, a low saturation magnetic flux density alloy thin film 6 having a saturation magnetic flux density Bs lower than that of the core is formed on the first core 1 and the soft core described above is formed on the second core 2. So-called EDG type MIG with magnetic thin film 4 formed
Type magnetic head. And the above-mentioned M
The same effect as that of the IG type magnetic head can be obtained. In this case, as the low saturation magnetic flux density alloy thin film 6, for example, a low saturation magnetic flux density amorphous thin film disclosed in Japanese Patent Application No. 63-311591 can be used, and excellent overwrite characteristics and high sensitivity can be obtained. To be

The magnetic head of the present invention is integrated with a slider as required and assembled into a head assembly. Floppy heads for overwriting such as tunnel erase type such as so-called laminate type or bulk type or read / write type without erase head, flying type computer head of monolithic type or composite type, rotary type VTR It is used as various magnetic heads such as heads and R-DAT heads. In this way, various known types of overwrite recording can be performed using the magnetic head of the present invention.

Next, the thin film magnetic head of the present invention will be described.

FIG. 4 shows a flying type thin film magnetic head which is a preferred embodiment of the present invention. The thin film magnetic head shown in FIG. 4 has an insulating layer 81, a lower magnetic pole layer 91,
Gap layer 10, insulating layer 83, coil layer 11, insulating layer 8
5, the upper magnetic pole layer 95 and the protective layer 12 are sequentially provided.

In the present invention, the slider 7 may be made of various conventionally known materials, for example, ceramics, ferrite or the like. In this case, ceramics, particularly ceramics containing Al ₂ O ₃ —TiC as a main component, ceramics containing ZrO ₂ as a main component, Si
Ceramics containing C as a main component or ceramics containing AlN as a main component are suitable. Incidentally, these may contain Mg, Y, ZrO ₂ , TiO ₂ or the like as an additive. Various conditions such as the shape and size of the slider 7 may be any known ones and are appropriately selected according to the application.

An insulating layer 81 is formed on the slider 7. As the material of the insulating layer 81, any conventionally known material can be used. For example, when a thin film is formed by a sputtering method, SiO ₂ , glass, Al ₂ O ₃ or the like can be used. The insulating layer 81 may have any known film thickness or pattern, for example, a film thickness of 5 to 40.
It is about μm.

The magnetic pole is usually the lower magnetic pole layer 9 as shown.
1 and the upper magnetic pole layer 95. In the present invention,
The above-mentioned MI is formed on the 91 and the top pole layer 95, respectively.
Similar to the case of the G type magnetic head or the EDG type MIG type magnetic head, the soft magnetic thin film of the present invention having the atomic ratio composition represented by the above formula is used. Therefore, a magnetic head having excellent overwrite characteristics and high recording / reproducing sensitivity can be obtained. Note that film formation, heat treatment, and the like may be performed in the same manner as above.

The patterns and film thicknesses of the lower and upper magnetic pole layers 91 and 95 may be any known ones. For example, the thickness of the lower magnetic pole layer 91 may be about 1 to 5 μm, and the thickness of the upper magnetic pole layer 95 may be about 1 to 5 μm. The gap layer 10 is formed between the lower magnetic pole layer 91 and the upper magnetic pole layer 95.

The gap layer 10 includes Al ₂ O ₃ and SiO.
Various known materials such as ₂ may be used. Further, the pattern, film thickness and the like of the gap layer 10 may be any known one. For example, the film thickness of the gap 10 is 0.2 to 1.0.
It may be about μm.

The material of the coil layer 11 is not particularly limited,
A metal such as Al or Cu which is usually used may be used. There are no restrictions on the winding pattern or winding density of the coil.
A known material may be appropriately selected and used. For example, the winding pattern may be any of a spiral type, a laminated type, a zigzag type, etc. other than the spiral type shown in the drawing. In addition, various vapor phase deposition methods such as a sputtering method and a plating method may be used to form the coil layer 11.

In the illustrated example, the coil layer 11 is a so-called spiral type and spirally forms the upper and lower magnetic pole layers 9.
The insulating layers 83 and 85 are provided between the coil layer 11 and the upper and lower magnetic pole layers 91 and 95.

As the materials for the insulating layers 83 and 85, any of the conventionally known materials can be used. For example, when a thin film is formed by a sputtering method, SiO ₂ , glass, A or the like is used.
1 ₂ O ₃ or the like can be used.

A protective layer 12 is provided on the upper magnetic pole layer 95. As the material of the protective layer 12, any conventionally known material can be used, and for example, Al ₂ O ₃ or the like can be used. In this case, as the pattern, the film thickness, etc. of the protective layer 12, any conventionally known one can be used. For example, the film thickness may be about 10 to 50 μm. In the present invention, various resin coat layers may be further laminated.

The manufacturing process of such a thin film magnetic head is as follows.
Usually, it is performed by thin film formation and pattern formation.
As described above, a vapor deposition method which is a conventionally known technique, for example, a vacuum vapor deposition method, a sputtering method, a plating method, or the like may be used for forming the thin film of each layer.

Pattern formation of each layer of the thin film magnetic head is as follows.
It can be performed by selective etching or selective deposition which is a conventionally known technique.

The etching can be performed by wet etching or dry etching.

The thin film magnetic head of the present invention is used in combination with a conventionally known assembly such as an arm.

Further, various types of overwrite recording can be performed by using the above-mentioned thin film magnetic head of the present invention. In this case, recording / reproducing can be effectively performed on a magnetic recording medium having a coercive force Hc of 800 Oe or more.

Further, in the present invention, a soft magnetic thin film is formed in a pattern between the non-magnetic substrates, or a pair of core halves having the soft magnetic thin film formed between the non-magnetic substrates are butted against each other. A magnetic circuit may be formed from a magnetic thin film to form a magnetic head.

[0108]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to specific examples of the present invention.

Example 1 As shown in FIG. 1, the first core 1 and the second core 2 having the soft magnetic thin film 4 formed on the surface facing the gap portion are joined and integrated with each other through the gap 5, and the MIG is formed. Type magnetic head was manufactured. The material of the cores 1 and 2 was Mn-Zn ferrite, the saturation magnetic flux density Bs at direct current was 5000 G, the initial magnetic permeability μ _i was 3000, and the coercive force Hc was 0.1 Oe. The soft magnetic thin film 4 was formed by RF magnetron sputtering and had a film thickness of 1 μm. In this case, the sputtering was carried out in an atmosphere containing an alloy of Fe _0.87 Zr _0.13 (atomic ratio) as a target and containing 13% by volume of N ₂ in Ar. The operating pressure was 0.5 Pa.

[0110] The composition of the samples No. 1 immediately after the film formation (atomic ratio), as shown in Table 1, Fe ₈₄ Zr ₈ N
_{Was eight} .

[0111]

[Table 1]

DC saturation magnetic flux density Bs, frequency 50 H
Coercive force Hc at z and initial permeability at frequency 5MHz μ _i
Is shown in Table 2 below.

[0113]

[Table 2]

The heat treatment temperature is 500 ° C. (Sample No. 1
2) and 600 ° C. (Sample No. 13), and the holding time was 60 minutes. Also, the measurement of magnetic properties, etc.
The soft magnetic thin film 4 was formed on the non-magnetic substrate under the same conditions as those for manufacturing the head. And EPM for composition analysis
VSM was used for A and Bs measurements, a BH tracer was used for Hc measurement, and an 8-shaped coil magnetic permeability meter (applied magnetic field 5 mOe) was used for μ _i measurement. The magnetostriction is ± 2 ×
Within 10 ⁻⁶ , the crystal grain size was 200 A or less.

Next, SiO ₂ is used for the gap 51,
It was formed by sputtering, and its film thickness was 0.3 μm.
An adhesive glass having a working temperature Tw of 650 ° C. was used for the gap 53. The gap 53 was formed by sputtering and its thickness was 0.1 μm.

The welding glass 3 has a working temperature Tw of 60.
72.50PbO-7.05 B ₂ O ₃ -14.57SiO ₂ -0.55Al ₂ O ₃ -2.75Z at 0 ℃
nO-0.05Bi ₂ O ₃ -2.50Na ₂ O-0.30Sb ₂ O ₃ (wt%),
Welding was performed at 600 ° C.

The number of coil turns was 20 × 2. Then, fix it on the calcium titanate slider.
After sealing, a composite type floating magnetic head was obtained.

A magnetic head manufactured in this way,
Using a hard disk having a coercive force of 1500 Oe, the following characteristics were measured with a track width of 14 μm. In the measurement, the first core 1 was on the hard disk reading side.

(Overwrite characteristic) 1.25 MHz 1
The f signal was recorded and then the 2f signal at 2.5 MHz was overwritten. The output of the 1f signal with respect to the output of the 2f signal was calculated, and the overwrite characteristics were evaluated.

(Measurement of Recording / Reproducing Sensitivity) A signal of 5 MHz is recorded, then the recorded signal is reproduced, and the reproduction output voltage value V ′ _PP (peak-to-peak) at that time is measured.
This measured value V ′ _PP is standardized to obtain V _PP .

The results are as follows. Overwrite _{characteristics: -40 dB V PP: 1.20μV /} μm / turn

Further, the sample was made to have a concentration of 5% (weight percentage).
When the surface of the soft magnetic thin film 4 was observed with an electron microscope after immersing it in the sodium chloride aqueous solution of No. 1 for 168 hours, almost no rust was confirmed in Sample No. 1 of the present invention. Further, when heat-treated at 750 ° C. for 60 minutes, Hc was less than 1 Oe.

Immediately after the film formation of sample No. 1 and 5
X-ray diffraction charts of the soft magnetic thin film 4 after heat treatment at 00 ° C. and 600 ° C. are shown in FIGS. 5, 6 and 7 . Looking at these charts, Fe (110) peak
As shown in Table 2, the relative intensities of the (200) peak are 2.0, 2.0 and 3.1, respectively, and the sample No. In No. 1, it can be confirmed that the (100) orientation is strong. Further, the (100) orientation was also recognized from the electron beam diffraction pattern.

Comparative Example Under the same conditions as in Example 1 except that the target composition of Example 1 and the amount of N ₂ in the atmosphere were changed, a sample of Fe ₇₅ Zr ₇ N ₁₈ was prepared and heat-treated at 600 ° C. As a result, the following results were obtained.

Bs: 16,000 GH Hc: 2.5 Oe μ _i (5 MHz): 1,000 Overwrite characteristics: −37 dB V _PP : 0.85 μV / μm / turn

The relative intensity of the Fe (200) peak to the Fe (110) peak of this product was 0. From these results, the effect of Fe (100) orientation is clear.

Example 2 In the same manner as in Example 1, the soft magnetic thin film and the metal-in
A gap type magnetic head was produced and the same measurement was performed. The thin film composition and the characteristic values immediately after the film formation are shown in Tables 1 and 2.

The relative intensity ratio of the Fe (200) peak to the Fe (110) peak after the heat treatment of the soft magnetic thin films of Sample Nos. 3 and 4 was 3 or more, and the (100) orientation was also found from the electron beam diffraction pattern. Admitted. The samples of the present invention also had good corrosion resistance.

In addition to the above, when a film was formed using targets having different M in the above composition formula, Mg, C
a, Ti, Hf, V, Nb, Ta, Cu, Mo, W, M
Similar results were obtained when one or more of n and B were contained, or when these and Zr were contained.

Embodiment 3 As shown in FIG. 3, the soft magnetic thin film 4 and the first core 1 in which the low saturation magnetic flux density alloy thin film 6 having a lower saturation magnetic flux density Bs than the core is formed on the gap facing surface are The formed second core 2 is joined and integrated through the gap 5,
A DG type metal-in-gap type magnetic head was manufactured. Then, when the same measurement as in Example 1 was performed, equivalent results were obtained.

Example 4 As shown in FIG. 4, the insulating layer 8 was sequentially formed on the slider 7.
1. A thin-film magnetic head having the lower magnetic pole layer 91, the gap layer 10, the insulating layer 83, the coil layer 11, the insulating layer 85, the upper magnetic pole layer 95, and the protective layer 12 was manufactured. In this case, a sputtering method is used to form each layer, and a pattern is formed.
Dry etching was used.

For the slider 7, Al ₂ O ₃ —TiC was used. The insulating layer 81 is made of Al ₂ O _{3 and} has a film thickness of 30.
μm. For the lower and upper magnetic pole layers 91, 95, soft magnetic thin films having the compositions of Sample Nos. 1, 3, 4 were used.

In this case, the lower and upper magnetic pole layers 91, 9
5 is formed by RF magnetron sputtering similarly to the soft magnetic thin film 4 of Example 1, and the lower and upper magnetic pole layers 91,
The film thickness of 95 was 3 μm.

The heat treatment condition is a heat treatment temperature of 350.
C., holding time 60 minutes. In the gap layer 10, S
The film thickness was set to 0.25 μm using iO ₂ . Coil layer 1
Cu was used for 1 and was formed in a spiral shape as shown in the drawing. Al ₂ O ₃ was used for the insulating layers 83 and 85. The protective layer 12 is made of Al ₂ O _{3 and} has a film thickness of 40 μm.
m.

Thus, the magnetic head sample of the present invention was manufactured. The coercive force of each of these samples is 1500
When the same measurement as in Example 1 was performed using an Oe hard disk, equivalent results were obtained.

Example 5 In accordance with Example 1, three types of compositions shown in FIG. 8 were deposited by RF magnetron sputtering. After the film formation, the gas released from the film was measured by mass spectrometry while the temperature was raised from room temperature to 800 ° C. at 20 ° C./min in vacuum. FIG. 8 shows the N ₂ partial pressure PN ₂ with respect to temperature and the film composition before and after heating. Comparing the film composition before and after heating, the composition A.y. Composition change of B is small, whereas composition C of y / x> 2.0
Then it changes a lot.

XRD after coating the films of A to C with SiO ₂ by about 100 mm and heating at 630 ° C. for 30 minutes is shown in FIG. A and C are (110) oriented, while B is (1
00) oriented. Further, FIG. 10 shows the heat treatment temperature dependency of μ5 MHz. It can be seen that B exhibits extremely high thermal stability as a result of the (100) orientation.

From the above results, the effect of the present invention is clear.

[0139]

The soft magnetic thin film of the present invention has extremely high heat resistance. In particular, since it has a strong (100) orientation, it has high saturation magnetic flux density, low coercive force, and high magnetic permeability, and has excellent soft magnetic properties. Furthermore, it has high hardness and high corrosion resistance. Further, it exhibits excellent soft magnetic properties immediately after film formation. Furthermore, when heat treatment is performed, its control is easy.

Therefore, the magnetic head of the present invention is easy to manufacture, has high overwrite characteristics, high recording / reproducing sensitivity, etc., and has excellent electromagnetic conversion characteristics and reliability.

Since the soft magnetic thin film of the present invention is excellent in corrosion resistance and abrasion resistance, a highly reliable magnetic head can be realized.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an example of a MIG type magnetic head of the present invention.

FIG. 2 is a partial cross-sectional view showing an example of a MIG type magnetic head of the present invention.

FIG. 3 is a partial cross-sectional view showing an example of an EDG type MIG type magnetic head of the present invention.

FIG. 4 is a partial cross-sectional view showing an example of a thin film magnetic head of the present invention.

FIG. 5 is a graph showing an X-ray diffraction chart of the soft magnetic thin film of the present invention.

FIG. 6 is a graph showing an X-ray diffraction chart of the soft magnetic thin film of the present invention.

FIG. 7 is a graph showing an X-ray diffraction chart of the soft magnetic thin film of the present invention.

FIG. 8 is a graph showing the relationship between the heat treatment temperature and the N ₂ partial pressure (PN ₂ ) of the present invention and the soft magnetic thin film, and the composition before and after heating.

FIG. 9 is a graph showing an X-ray diffraction chart of the soft magnetic thin film of the present invention and the comparative soft magnetic thin film.

FIG. 10 is a graph showing the relationship between the heat treatment temperature of the soft magnetic thin films of the present invention and comparative examples and μ5 MHz.

[Explanation of symbols]

1st core 2 second core 3 fused glass 4 Soft magnetic thin film 5, 51, 53 gap 6 Low saturation magnetic flux density alloy thin film 7 slider 81, 83, 85 insulating layer 91 Lower magnetic pole layer 95 Top pole layer 10 Gap layer 11 coil layers 12 Protective layer

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01F 10/00-10/32 H01F 41/14-41/34 G11B 5/31-5/325

Claims (6)

(57) [Claims] 1. The atomic ratio composition immediately after thin film formation is calculated by the following formula.
A thin film for a magnetic head characterized by being represented . Formula (Fe100-zNiz) 100-x-yMxNy (M in the above formula is Mg, Ca, Ti, Zr, Hf, V, Nb, Ta,
One or more selected from Cr, Mo, W, Mn and B,
6.5 ≦ x ≦ 14, 6.2 ≦ y ≦ 15, 0.7 ≦ y / x ≦
1.5 and 0 ≦ z ≦ 10. ) 2. A to have the atomic ratio represented by the following formula
A soft magnetic thin film is provided, and this thin film is heat treated for X-ray diffraction.
Of the Fe (200) peak to the Fe (110) peak
A method of manufacturing a thin film for a magnetic head, wherein the relative intensity ratio is increased to 1 or more . Formula (Fe100-zNiz) 100-x-yMxNy (M in the above formula is Mg, Ca, Ti, Zr, Hf, V, Nb, Ta,
One or more selected from Cr, Mo, W, Mn and B,
6.5 ≦ x ≦ 14, 6.5 ≦ y ≦ 15, 0.7 ≦ y / x ≦
1.5 and 0 ≦ z ≦ 10. ) 3. A soft magnetic thin film having an atomic ratio composition represented by the following formula is provided, and this thin film is heat-treated for electron diffraction.
A method of manufacturing a thin film for a magnetic head, comprising increasing the Fe (200) plane orientation . Formula (Fe100-zNiz) 100-x-yMxNy (M in the above formula is Mg, Ca, Ti, Zr, Hf, V, Nb, Ta,
One or more selected from Cr, Mo, W, Mn and B,
6.5 ≦ x ≦ 14, 6.5 ≦ y ≦ 15, 0.7 ≦ y / x ≦
1.5 and 0 ≦ z ≦ 10. ) 4. The thin film according to claim 1 between a pair of cores.
A magnetic head having . 5. An upper magnetic pole layer, a lower magnetic pole layer, and a protective layer.
A thin film magnetic head having, Oyo the upper magnetic layer
The lower magnetic pole layer and the lower magnetic pole layer according to any one of claims 1 to 3.
A magnetic head characterized by being formed of a thin film . 6. The method according to claim 1 , which is formed on a substrate.
A magnetic circuit is formed by any of the thin films described in
Magnetic head .