JPH04106708A - Soft magnetic thin film and magnetic head - Google Patents

Abstract

PURPOSE:To obtain the soft magnetic thin film having a high saturation magnetic flux density, high heat resistance and corrosion resistance and excellent soft magnetic characteristics by using Fe-Co-N having a specific atomic ratio compsn. CONSTITUTION:The soft magnetic thin film has the atomic ratio compsn. expressed by formula. In the formula, M is >=1 kinds selected from Mg,Ca,Ti,Zr, Hf,V,Nb,Ta,Cr,Mo,Mn,and B. In the formula, (x) is 0.2 to 0.7 and the saturation magnetic flux density Bs decreases if (x) is not within this range; (y) is 0 to 0.2 and the Bs tends to decrease if (y) exceeds this range; (z) is 0.001 to 0.15 and the heat resistance is insufficient if (z) is below this range; (v) is 0 to 0.1 and the Bs decreases and the soft magnetic characteristics tend to degrade if (v) exceeds this range; (w) is 0.001 to 0.15 and there is the tendency that the soft magnetic characteristics are not obtainable if (w) exceeds this range.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to soft magnetic thin films and magnetic heads, especially metal magnetic heads.
The present invention relates to in-gap (MIG) type magnetic heads, enhanced dual gap length (EDG) type magnetic heads, and thin film magnetic heads.

<Prior Art> A MIG type magnetic head is known which has a soft magnetic thin film such as Sendust, which has a higher saturation magnetic flux density Bs than the core, on the opposing face of the gap portion of at least one of first and second cores made of ferrite.

In this magnetic head, 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 a medium having a high coercive force.

Furthermore, floating type thin film magnetic heads have been put into practical use, and have excellent characteristics such as being capable of high-density recording and high-speed data transfer.

In order to generate high-density magnetic flux even in a thin-film magnetic head, a soft magnetic thin film such as permalloy or sendust having a high saturation magnetic flux density B is used for the upper and lower magnetic pole layers.

Incidentally, the saturation magnetic flux density Bs of such a soft magnetic thin film used in a magnetic head is about 12,000G at most.

For this reason, conventional magnetic heads have insufficient electromagnetic conversion characteristics such as override characteristics, and particularly in the case of magnetic recording media having high coercive force, an even higher saturation magnetic flux density Bs is required.

By the way, targeting Fe, Ar and N.

By sputtering in a mixed gas of , it is possible to obtain a Fe--N soft magnetic thin film with a saturation magnetic flux density B even higher than that of sendust.

This is because by mixing N, the crystal grains of Fe are made finer and the magnetic anisotropic dispersion is reduced.

For example, JP-A-64-15907 discloses a soft magnetic thin film containing iron nitride mainly composed of Fe and Fe<N and/or Fe5N.

This soft magnetic thin film has a saturation magnetic flux density of 15,000
G or more, and has a low coercive force Hc (having magnetic properties suitable for use in the magnetic head).

However, the Fe-N soft magnetic thin film has low heat resistance, about 350
At a temperature of about 0.degree. C., the crystal grain size increases and the coercive force Hc increases rapidly.

Therefore, by heat treatment such as glass welding, the
MIG type magnetic heads and EDGs that are kept at temperatures around ℃
It is difficult to use this type of magneto-electromagnetic head in a thin-film magnetic head which is subjected to a temperature of about 350° C. or higher during a film forming process such as sputtering.

In addition, Co-N, Fe-Co, Fe-Co-
It is known that a soft magnetic thin film such as N has a high saturation magnetic flux density Bs and exhibits soft magnetism. Especially Fes. C
The composition around a6° is 240, which is the highest among magnetic materials.
A saturation magnetic flux density of about 00G can be obtained.

However, the Co--N soft magnetic thin film has low heat resistance, similar to the Fe--N soft magnetic thin film described above.

In addition, Fe-Co and Fe-Co-N soft magnetic thin films are
Insufficient soft magnetic properties.

<Problems to be Solved by the Invention> An object of the present invention is to provide a soft magnetic thin film having a high saturation magnetic flux density Bs, high heat resistance and corrosion resistance, and excellent soft magnetic properties, and a method using such a soft magnetic thin film. As a result, it is an object of the present invention to provide an MIG type magnetic head and an EDG type magneto-electromagnetic head having a soft magnetic thin film having a low coercive force He and a high saturation magnetic flux density Bs.

<Means for Solving the Problems> Such objects are achieved by the following inventions (1) to (4).

(1) A soft magnetic thin film characterized by having an atomic composition represented by the following formula.

Formula (Fe1-++-y-*COJ1yMz)+-
w(N+-vojw (In the above formula, M is Mg, Ca,
Ti, Zr, Hf, ■, Nb, Ta, Cr, Mo, Mn
and one or more selected from B, and 0.2≦x≦0
．． 7.0≦y≦02. 0.001≦z≦0.15.0≦v≦0.1.0.00
1≦w≦0.15. ) (2) The soft magnetic thin film according to (1) above, which has a saturation magnetic flux density Bs of 20,000G or more and a coercive force Hc of 20e or less.

(3) A magnetic head characterized by having the soft magnetic thin film described in (1) or (2) above between a pair of cores.

(4) A thin film magnetic head having an upper magnetic pole layer, a lower magnetic pole layer, and a protective layer, wherein the upper magnetic pole layer and the lower magnetic pole layer are formed of the soft magnetic thin film described in (1) or (2) above. A magnetic head characterized by:

Effect> The soft magnetic thin film particularly suitable for the magnetic head of the present invention is Fe-
Since it is Co--N based, the saturation magnetic flux density Bs is very high.

And Fe and C to Fe, CO and N.

By adding an appropriate amount of an element that forms a more stable nitride, the soft magnetic properties are improved while the saturation magnetic flux density Bs remains approximately 20,000 G or more, and the heat resistance and corrosion resistance are further improved.

Here, the temperature at which the coercive force changes rapidly due to heat treatment,
For example, assuming that the heat treatment temperature at which the coercive force He becomes 20e is the heat-resistant temperature, the heat-resistant temperature of the soft magnetic thin film used in the present invention is approximately 500° C. or higher.

Therefore, the soft magnetic thin film of the present invention has excellent soft magnetic properties such as a high saturation magnetic flux density Bs, a low coercive force Hc, and a high magnetic permeability μ.

Therefore, the magnetic head of the present invention having such a soft magnetic thin film has high override characteristics, high recording/reproducing sensitivity, and excellent N, especially for high coercive force magnetic recording media.
Has magnetic conversion properties.

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

In addition, Japanese Patent Application Laid-open No. 60-218820 and No. 60-22
Publication No. 0913 discloses a magnetic thin film containing Fe, 2 to 10% by weight of Aρ, 3 to 16% by weight of Si, and 0005 to 4% by weight of nitrogen.

It is also stated that by replacing a part of Fe with CO, the saturation magnetic flux density Bs can be improved, and by replacing it with N1, the magnetic permeability μ can be maintained at a high state without decreasing Bs. .

However, although the specific example shown in the examples has a high resistance temperature, the saturation magnetic flux principal Bs is about 12,000G at most.

There is no known soft magnetic 1 thin film that has such a high saturation magnetic flux density Bs (low coercive force Hc, high magnetic permeability μ, and excellent heat resistance).

<Specific structure of the invention> Hereinafter, the specific configuration of the present invention will be explained in detail.

A soft magnetic thin film particularly suitable for a magnetic head of the present invention has an atomic composition represented by the following formula.

Formula (Fe knee x-y-zcOJl, yN), -
w(N, -vOv)W In the above formula, S5 is Mg, Ca
, Ti, Zr, Hf, ■, Nb, Ta,
One or more types selected from Cr, Mo, Mnj-5 and B.

Or Zr is so cute.

Elements other than those mentioned above will not provide the effects of the present invention, especially the heat resistance.

Also, X is 02 to 07, preferably 03-06.

Outside the above range, the saturation-bundle heat Bs decreases. For this reason, when applied to a magnetic head, override characteristics tend to deteriorate.

y is 0-02, preferably 0-01.

By adding Ni, the silver transparency 'Xμ can be improved.

However, when the above range is exceeded, the saturation magnetic flux density Bs tends to decrease.

In addition, when \l is referred to as an essential component, its content y
is preferably 001-02, more preferably 001-01.

2 is 0.001 to 0.15, preferably T1 and 10.01 to 01 from the viewpoint of heat resistance.

If it is less than the above range, heat resistance will be insufficient.

For this reason, the soft magnetic properties deteriorate due to heat treatment, etc., and the coercive force H
c tends to increase significantly.

Beyond the above range, the saturation magnetic flux density BS decreases.

Therefore, when applied to a magnetic head, override characteristics tend to deteriorate.

V is O-Ol, preferably 0-005.

By adding ○, the coercive force Hc tends to decrease and the magnetic permeability μ tends to increase.

However, if it exceeds the above range, Bs decreases and the soft magnetic properties tend to deteriorate.

In addition, when 0 is included as an essential component, its content V
is 0,001-01, more preferably 0.01-005
It is preferable that

W is 0001 to O15, preferably It is 0.03 to 0.07.

If it is less than the above range, grain refinement by N is insufficient and soft magnetic properties tend not to be obtained.

If the above range is exceeded, nitrides of Fe, Co, Ni, and M are produced in excess of the necessary amount, so that soft magnetic properties tend not to be obtained.

Furthermore, even if 5 at% or less of Sl and/or 2 at% or less of Ar2 is contained, as long as the composition is within the above-mentioned range,
You can get the same effect as Habo.

The composition of the soft magnetic thin film of the present invention is, for example, El
ectron Probe Micro Analyzes
is (may be measured by the EPMAJ method.

Further, the thickness of the soft magnetic thin film may be appropriately selected depending on the application, etc., but is usually about 0.1 to 10-.

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

Among these, it is particularly preferable to form the film by sputtering, and for example, the film may be formed as follows.

As the target, an alloy cast body, a sintered body, a multi-dimensional target, etc. are used. Then, sputtering is performed in an inert gas atmosphere such as Ar.

Further, when performing reactive sputtering, the composition of the target may be approximately the same as that in the above-mentioned formula without containing N or 0.

Then, sputtering is performed using N2 or N2 in Ar.
and 02 in an atmosphere containing 01 to 15% by volume, preferably 2 to 10% by volume.

Outside the above range, soft magnetic properties tend not to be obtained.

There are no particular restrictions on the sputtering method, and there are no restrictions on the sputtering equipment to be used either, and a normal one may be used.

Note that the operating pressure may normally be about 01 to 10 Pa.

In this case, various conditions such as sputtering voltage and current are appropriately determined depending on the sputtering method and the like.

After film formation, the soft magnetic thin film is preferably subjected to heat treatment.

The following conditions are particularly suitable for the heat treatment conditions.

Temperature increase rate 2~b Holding temperature: about 200-700'C Holding time: about 10 to 60 minutes Cooling rate・2~b Note that the atmosphere may be an inert gas such as Ar.

By performing heat treatment under the above conditions, even more (!
A soft magnetic thin film with excellent soft magnetic properties can be obtained.

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

Coercive force He (50Hz): about 0.1 to 20e, especially about 0.1 to 10e Initial magnetic permeability u, (5M) Iz) about 1000 to 3000 Saturation magnetic flux density Bs (DC): about 20000G to 23000G Crystal Average crystal grain size D = about 100 to 300 people, especially about 150 to 250 people Heat resistance temperature = about 450 to 700℃, especially about 500 to 700℃ Heat resistance temperature refers to the coercive force Hc when heat treatment is performed This is the temperature at which Hc increases rapidly, and in the above case is the temperature at which the coercive force Hc becomes 20e.

To measure the magnetic properties of a soft magnetic thin film, for example, when applying it to a magnetic head, the film is formed on a non-magnetic substrate under the same conditions as when forming a magnetic head, and after heat treatment under the same conditions, the following method is used: Just follow the steps below.

Initial magnetic permeability (μm): Measured using a figure-8 coil permeability meter with an applied magnetic field of 5 mOe Coercive force (Hc): Measured using a B-H tracer Saturation magnetic flux density (Bs): Using VSM, 10000G Further, the average crystal grain size of the crystal grains can be determined by measuring the bcc (110) peak half width W s o of the X-ray diffraction line by a powder method, and using the following Scherrer equation.

Formula D=0. 9 /W sa cosθ In the above formula, e is the wavelength of the X-ray used, and θ is the diffraction angle.

Note that when CuKα is used, bcc The (110) peak at 20 is approximately 45 degrees.

The soft magnetic thin film of the present invention is particularly applicable to various magnetic heads such as MIG (metal-in-gap) type magnetic heads and thin-film magnetic heads.

In addition to magnetic heads, the present invention can also be applied to various soft magnetic components such as thin film inductors.

Next, the magnetic head of the present invention will be explained.

A preferred embodiment of the MIG type magnetic head of the present invention is shown in FIGS. 1 and 2.

The magnetic head shown in FIG. 1 has a first core 1 and a second core 2 having a soft magnetic thin film 4 formed on the surface facing the gap, and both cores are joined through a gap 5. , are welded and integrated by welding glass 3.

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

In the present invention, the core 1.2 is preferably composed of ferrite.

In this case, there are no particular restrictions on the ferrite used, but Mn
-Zn ferrite or Ni-Zn ferrite is preferably used depending on the purpose.

As M n -Z n ferrite, FexOs50
It is preferable to use ZnO in an amount of about 60 mol %, about 8 to 25 mol % of znO, and the remainder being substantially MnO.

In addition, N1-Zn ferrite exhibits excellent properties particularly in the high frequency range, and its preferred composition is 30 to 60 mol% of Fe 203 and 15 to 60 mol% of NiO.
ZnO is about 50 mol% and ZnO is about 5 to 40 mol%.

The DC saturation magnetic flux density Bs of the core 1.2 is preferably 3,000 to 6,0OOG.

If the saturation magnetic flux density is not within the above range, the override characteristics will deteriorate, and with a composition having such a saturation magnetic flux density, the Curie temperature will become low, resulting in a decrease in thermal stability. If the above range is exceeded, the magnetostriction becomes a force increaser, resulting in deterioration of the characteristics of the magnetic head or a tendency to cause TM.

The core 1.2 preferably has an initial magnetic permeability ul of 1.000 or more and a coercive force Hc of 0.30e or less at direct current.

Further, it is preferable that the surface of the core 1.2 facing the gap portion be smoothed by mirror polishing or the like so that a soft magnetic thin film 4, a base film, etc., which will be described later, can be easily formed thereon.

The soft magnetic thin film 4 generates high-density magnetic flux during recording,
Magnetism with high coercive force! It is provided for effective recording on self-recording media.

As the soft magnetic thin film 4, the soft magnetic thin film of the present invention described above is used.

The saturation magnetic flux density Bs of the soft magnetic thin film 4 when the magnetic head is completed is preferably 20,000 G or more.

If it is less than the above range, the override characteristics will deteriorate, making it particularly difficult to record on a high coercive force magnetic recording medium.

Further, in order to have even higher soft magnetic properties, the average crystal grain size of the crystal grains of the soft magnetic thin film 4 is preferably about 100 to 300 grains.

In addition, 50H of the soft magnetic thin film 4 when the magnetic head is completed.
The coercive force Hc at z is 20e or less, more preferably l
It is preferable that it is Oe or less.

The soft magnetic thin film 4 preferably has an initial magnetic permeability μ of 1000 or more at 5 MHz.

If the coercive force Hc exceeds the above range, or the initial permeability μ
is less than the above range, recording/reproducing sensitivity tends to decrease.

The thickness of the soft magnetic thin film 4 is preferably 0.2 to 5-1, more preferably 0.5 to 3-1.

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 is likely to be saturated, making it difficult to fully perform the function of the MIG type magnetic head.

Moreover, when the above range is exceeded, not only the wear of the soft magnetic thin film 4 increases, but also the eddy current loss increases.

By having the soft magnetic thin film 4 having such a high saturation magnetic flux density, the magnetic head of the present invention can perform effective recording on a magnetic recording medium with a coercive force of 10,000 e or more, particularly 1,500 to 20,000 e.

If the core 1, core 2, and soft magnetic thin film 4 have magnetic properties as described above, high output and resolution can be obtained as a magnetic head. Moreover, a good value of -35 dB or less can be obtained for the override characteristic.

Note that the resolution refers to the output of the first layer signal, for example, ■8.2
When the output of the layer signal is V@t, (V zr/V
+t) ×100 [%].

In addition, the override characteristic is, for example, 1 for the 2nd layer signal output when a signal is overwritten by 2 on the 1st layer signal.
This is the layer signal output.

Gap 5 is formed from a non-magnetic material.

In particular, it is preferable to use adhesive glass for the gap 5 in order to increase adhesive strength.
Glasses shown in No. 06 and the like are suitable.

Further, the gap 5 may be formed of only adhesive glass, but in order to increase the gap formation speed and gap strength, it is preferably formed of two layers, a gap 51 and a gap 53, as shown in the figure.

In this case, it is preferable to use 5102 for the gap 51 and use adhesive glass for the gap 53.

Incidentally, in the case of a magnetic head of a type in which welded glass 3, which will be described later, flows into both sides of the gap, the gap 5 may be formed only of silicon oxide.

Although there are no particular restrictions on the method for forming the gap 5, it is preferable to use a sputtering method.

The gap length is usually about 0.2 to 2.0.

In the MIG type magnetic head of the present invention, as shown in FIGS. 1 and 2, the first core 1 and the second core 2 have a gap 5
They are joined and integrated via the .

The cores are usually joined together by thermocompression bonding using adhesive glass in the gap 53 and at the same time by pouring the welding glass 3.

The working temperature Tw of the welding glass 3 used is 450 to 700°C.
In particular, it is preferably about 460 to 650''C.

Here, the working temperature Tw is, as is well known, the temperature at which the viscosity of the glass becomes 10' poise.

In the present invention, since the above-mentioned soft magnetic thin film 4 having high heat resistance is used, even if such Tw glass is used for welding, the coercive force Hc maintains a value of 20e or less, particularly 10e or less.

Although there are no particular limitations on the welded glass 3, it is preferable to use lead silicate glass.

Among these, for example, the glasses shown below are suitable.

PbO: about 67.5 to 87.5 overlapping % B20. :4.
O~8.1% by weight S x 02: 7.5~13.6% by weight A at 203 ・0.3~0.8% by weight ZnO: 2.2
~3.3% by weight B15on: O ~ 0.1% by weight Na * 0, K * O, CaO, etc.: 0 ~ 4% by weight 5bxOs: O ~ 1% by weight The temperature is set to around the working temperature Tw, and the usual method is used.

In this case, the welding process may also serve as 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 lower saturation magnetic flux density Bs than the core is formed on the first core l, and the above-mentioned soft magnetic thin film is formed on the second core 2. 4 can be used as a so-called EDG type MIG type magnetic head.

Further, the same effects as those of the above-mentioned MIG type magnetic head can be obtained.

In this case, the low saturation magnetic flux density alloy thin film 6 can be, for example, a low saturation magnetic flux density amorphous thin film shown in Japanese Patent Application No. 63-311591, and excellent override characteristics and high sensitivity can be obtained. .

The magnetic head of the present invention is integrated with a slider as necessary and assembled into a head assembly.

In addition, there are floppy heads that perform override recording such as tunnel erase types such as laminate types and bulk types, or read/write types that do not have an erase head, floating type computer heads such as monolithic types and composite types, and rotary type VTR heads. It is used in various magnetic heads such as heads for R-DAT and R-DAT.

In this way, using the above magnetic head of the present invention,
Override recording can be performed using various known methods.

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

FIG. 4 shows a floating type thin film magnetic head which is a preferred embodiment of the present invention.

The thin film magnetic head shown in FIG.
Insulating layer 81, lower magnetic pole layer 91, gear layer lO1 insulating layer 83, coil layer 11, insulating layer 85, upper Ff! i-pole layer 9
5 and protection N12 in sequence.

In the present invention, the slider 7 may be made of various conventionally known materials (eg, made of ceramics, ferrite, etc.).

In this case, ceramics, in particular ceramics based on A4gosTiC, ZrO.

Ceramics containing as a main component, ceramics containing SiC as a main component, or ceramics containing Af2N as a main component are suitable. In addition, these contain Mg as an additive.
, Y, Zr0zT i Oa, etc. may be contained.

Conditions such as the shape and size of the slider 7 may be of any known size and are appropriately selected depending on the application.

An insulating layer 81 is formed on the slider 7.

As the material for the insulating layer 81, any conventionally known material can be used. For example, when a thin film is formed by sputtering, S f Oz, glass, 8 de 203, etc. can be used.

The thickness and pattern of the insulating layer 81 may be any known ones, and for example, the thickness is about 5 to 40 mm.

The magnetic poles are usually provided as a lower magnetic pole N91 and an upper magnetic pole layer 95 as shown.

In the present invention, the lower magnetic pole layer 91 and the upper magnetic pole layer 95 include the aforementioned MIG type magnetic head and EDG type magnetic head, respectively.
As in the case of the IG type magnetic head, the soft magnetic thin film of the present invention having the atomic ratio composition expressed by the above formula is used.

Therefore, a magnetic head with excellent override characteristics and high self-recording/reproduction sensitivity can be obtained.

Note that film formation, heat treatment, etc. may be performed in the same manner as described above.

The patterns, film thicknesses, etc. 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 approximately 1 to 5 mm, and the thickness of the upper magnetic pole layer 95 may be approximately 1 to 5 mm.

A gap layer 10 is formed between the lower magnetic pole layer 91 and the upper magnetic pole layer 95.

The gap layer 10 has Aj220s and Si○.

Various known materials may be used.

Further, the pattern, film thickness, etc. of the gap layer 10 may be any known ones. For example, the film thickness of the gap 10 may be approximately 0.2 to 1,0-.

There is no particular restriction on the material of the coil layer 11, and a commonly used metal such as octabeta or Cu may be used.

There are no restrictions on the winding pattern or winding density of the coil, and five known patterns may be selected and used as appropriate. For example, the winding pattern may be a spiral type as shown in the figure, a laminated type, a zigzag type, or the like.

Further, the coil layer 11 may be formed using various gas phase wave @ methods such as sputtering method, plating method, or the like.

In the illustrated example, the coil layer 11 is a so-called spiral type, and is spirally arranged between the upper and lower magnetic pole layers 91.95, and the insulating layer 83. 85 are installed.

Any conventionally known material can be used for the insulating layers 83 and 85. For example, when a thin film is formed by sputtering, S i 02. Glass, An! O
, etc. Also, a protection layer 11112 is provided on the upper magnetic pole layer 95. Any conventionally known material can be used as the material for the protection N12, such as Ag203.

In this case, any conventionally known pattern and film thickness of the protective layer 12 can be used; for example, the film thickness is 10 to 5.
It may be about 0-.

By the way, when forming the protection M12 by sputtering, for example, since it is exposed to plasma, the
It is placed at a temperature of about 0°C.

Therefore, in the present invention, the upper and lower magnetic pole layers 91.9
5, the above-mentioned soft magnetic thin film with high heat resistance is used.

In addition, in the present invention, various resin coat layers and the like may be further laminated.

The manufacturing process of such a thin film magnetic head is usually performed by thin film fabrication and pattern formation.

As described above, the thin film of each layer may be formed using a conventionally known technique such as a vapor deposition method such as a vacuum evaporation method, a sputtering method, or a plating method.

Pattern formation of each layer of the thin film magnetic head can be performed by selective etching or selective deposition, which are conventionally known techniques. 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.

Furthermore, various types of override recording can be performed using the thin film magnetic head of the present invention. In this case, the coercive force Hc is 10000e or more, especially 150e
Effectively records and records on magnetic recording media of 0 to 20,000e.
Can be played.

<Example> Hereinafter, the present invention will be explained in further detail by giving specific examples of the present invention.

Example 1 As shown in FIG. 1, a first core 1 and a second core 2 having a soft magnetic thin film 4 formed on the surface facing the gap are joined together via a gap 5, and an MIG type Manufactured a magnetic head.

The material of cores 1 and 2 is Mn-Zn ferrite, the saturation magnetic flux density B8 at DC is 5000G, and the initial magnetic permeability μm is 30.
00, and the coercive force Hc was 010e.

The soft magnetic thin film 4 was formed by RF magnetron sputtering, and the film thickness was 1 mm.

In this case, sputtering is F e a, ssc Oo, soZ r o, o
s (atomic ratio) as a target, and N2 in Ar.
The test was carried out in an atmosphere containing 5% by volume of. The operating pressure is
The pressure was set at 0.4 Pa.

The composition of the soft magnetic thin film 4, the saturation magnetic flux density Bs at direct current, the coercive force Hc at a frequency of 50 Hz, the initial magnetic permeability μ at a frequency of 5 MHz, and the heat resistance temperature are as shown in Table 1.

Note that Bs, Hc, and μm are values after welding heat treatment. In this case, the heat treatment temperature was 500°C and the holding time was 60°C.
It was set as 1 minute.

In addition, the heat-resistant temperature is Hc after 60 minutes of heat treatment.
This is the heat treatment temperature when Hc becomes 20e or more.

Note that measurements of magnetic properties and the like were performed by forming a soft magnetic thin film 4 on a nonmagnetic substrate under the same conditions as in the head production.

EPMA is used for compositional analysis, and VS is used for Bs measurement.
A B-H tracer was used to measure M and Ha, and a figure-8 coil permeability meter (applied magnetic field of 5 m0e) was used to measure μ.

The gap 51 was formed by sputtering using Sin, and its film thickness was set to 0.3-.

For the gap 53, adhesive glass having a working temperature Tw of 550° C. was used.

Note that the gap 53 was formed by sputtering, and its film thickness was set to 01-.

The welding glass 3 has a working temperature Tw of 500°C, 77,
5DPbO-6,058203-10,57SiO□-
0,55AgiOs-2,75ZnO-0,05Bi2
0-2.5ONa20-0.30SbzOx (wt%
), and welding was performed at 500''C.

Further, the number of coil turns was 20×2 turns.

Then, it was fixed and sealed to a slider made of calcium titanate to obtain a composite type floating magnetic head.

The magnetic heads manufactured in this way were sample No.
Set to 1.

In addition, magnetic head samples No. 2 to No. 9 with different compositions of soft magnetic thin @4 and comparative sample No.

IO~No. 16 were also manufactured.

Using each of these samples and a hard disk having a coercive force of 180° Oe, the following characteristics were measured at a track width of 14-.

Note that during the measurement, the first core 1 was placed on the hard buisness freeing side.

(Override characteristics) A 1.25 MHz 1f signal was recorded, and then a 2.5 MHz 2 signal was overwritten on top of this.

The If signal output with respect to the 2f signal output was calculated, and the override characteristics were evaluated.

(Measurement of recording/playback sensitivity) Record 3 5 MHz signals, then play back the recorded signals, and check the positive value of the playback a at that time V'p-p (beak
two peaks).

In addition, in the table, the value y p which normalized the measured value V', -,
−p is indicated.

The results are shown in Table 1.

Table 1 clearly shows the effects of the present invention.

In addition, after immersing the sample in a sodium chloride aqueous solution with a concentration of 5% (weight percentage) for 168 hours, the surface of the soft magnetic thin film 4 was observed with an electron microscope, and it was found that comparative sample No.
In No. 10 to No. 15, the occurrence of rust was confirmed.

In contrast, samples N051 to No. of the present invention.

No. 9, almost no rust was observed.

In addition, various samples with different compositions of the soft magnetic thin film 4 were manufactured and similar evaluations were performed, and similar results were obtained.

Example 2 As shown in FIG. 3, a first core l was formed with a low saturation magnetic flux density alloy thin film 6 having a lower saturation magnetic flux density Bs than the core on the opposing surface of the gap part, and a soft magnetic thin film 4 was formed. A second core 2 is joined and integrated through a gap 5,
An EDG type MIG type magnetic head was manufactured.

Then, when the same measurements as in Example 1 were performed, the same results were obtained.

Embodiment 3 As shown in FIG. 4, an insulating layer 81, a lower magnetic pole layer 91 . gap layer 10, insulating layer 83,
A thin film magnetic head having a coil layer 11, an insulating layer 85, an upper pole layer 95, and a protective layer 12 was manufactured. In this case, sputtering was used to form each layer, and dry etching was used to form patterns.

For the slider 7, Aβgoz-TiC was used.

AQ20s was used for the insulating layer 81, and the film thickness was 30 mm.

For the lower and upper magnetic pole layers 91.95, soft magnetic thin films having the compositions shown in Table 2 were used.

In this case, the lower and upper magnetic pole layers 91.95 were formed by RF magnetron sputtering similarly to the soft magnetic thin film 4 of Example 1, and the film thicknesses of the lower and upper magnetic pole layers 91.95 were each 3-.

The saturation magnetic flux density Bs at direct current, coercive force Hc at a frequency of 50 Hz, initial magnetic permeability μm at a frequency of 5 MHz, and allowable temperature limit of the magnetic pole layer 91.95 are as shown in Table 2.

The heat treatment conditions are: heat treatment temperature 350°C, holding time 6
The duration was 0 minutes.

For the gap layer IO, 5iO= is used, and the film thickness is 0.25
−.

The coil layer 11 was made of Cu and was formed into a spiral shape as shown in the figure.

A120x was used for the insulating layers 83 and 85.

In addition, A(!,2ON) was used for the protective layer 12, and the film thickness was set to 40.degree. C. during the manufacturing process. .

In this way, magnetic head sample No. 1 of the present invention
~ No. 9 and comparison sample No. 10 ~ No. 1
5 was manufactured.

The same measurements as in Example 1 were performed using each of these samples and a hard disk having a coercive force of 18,000e.

The results are shown in Table 2.

Table 2 clearly shows the effects of the present invention.

Moreover, the samples of the present invention also had good corrosion resistance.

<Effects of the Invention> The soft magnetic thin film of the present invention has a high saturation magnetic flux density Bs. In addition, due to its high heat resistance, the coercive force Hc is low and the magnetic permeability μ
It has excellent soft magnetic properties.

Therefore, the magnetic head of the present invention has high override characteristics, high recording/reproduction sensitivity, and excellent electromagnetic conversion characteristics, especially for magnetic recording media with high coercive force.

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

[Brief explanation of drawings]

FIGS. 1 and 2 are partial cross-sectional views showing an example of the MIG type magnetic head of the present invention. FIG. 3 shows one of the EDG-type MIG-type magnetic heads of the present invention.
It is a partial sectional view showing an example. FIG. 4 is a partial sectional view showing an example of the thin film magnetic head of the present invention. Explanation of symbols l...First core 2...Second core 3...Welded glass 4...Soft magnetic thin film 5.51.53...Gap 6...Low saturation magnetic flux enrichment alloy thin film 7 ...Slider 81, 83, 85...Insulating layer 91...Lower magnetic pole layer 95...Upper magnetic pole layer 10...Gap layer 1...Coil layer 2...-Protective layer applicant T.D. K Co., Ltd. agent

Claims (4)

[Claims] (1) A soft magnetic thin film characterized by having an atomic composition represented by the following formula. Formula (Fe_1_-_x_-_y_-_zCo_xNi_
yM_z)_1_-_w(N_1_-_vO_v)_w
(In the above formula, M is one or more selected from Mg, Ca, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, Mn, and B, and 0.2≦x≦0.7
, 0≦y≦0.2, 0.001≦z≦0.15, 0≦v≦0.1, 0.00
1≦w≦0.15. ) (2) The soft magnetic thin film according to claim 1, wherein the saturation magnetic flux density Bs is 20,000 G or more and the coercive force Hc is 2 Oe or less. (3) A magnetic head comprising the soft magnetic thin film according to claim 1 or 2 between a pair of cores. (4) A thin film magnetic head comprising an upper magnetic pole layer, a lower magnetic pole layer, and a protective layer, wherein the upper magnetic pole layer and the lower magnetic pole layer are formed of the soft magnetic thin film according to claim 1 or 2. A magnetic head characterized by: