JP3316869B2 - Magnetoresistive 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 magnetic head for a magnetic recording apparatus, and more particularly to an improvement in an Nb material used for the same, and provides a magnetoresistive head suitable for reading high density magnetic recording. The Nb material of the present invention is particularly used for a shunt film of a magnetic head using a shunt bias type magnetoresistive element having a shunt film for bias application. It is also used as an intermediate film between a soft magnetic film and a magnetoresistive film of a magnetic head using a soft bias type magnetoresistive element having a soft magnetic film for bias application.

[0002]

2. Description of the Related Art For example, US Pat. No. 4,663,684 discloses a shunt film of a conventional shunt bias type magnetoresistive head.
As described in No. 2, Ti, Ta, Mo, Nb, etc., in JP-A-2-68706, Ti, Cr, Ta, Zr, Hf, TiW alloy and the like, in JP-A-2-220213. Cr, Ta, W, Nb and the like are used.

[0003] As a magnetoresistive film, a Ni-Fe alloy film or N
An i-Co alloy film or a Ni-Fe-Co film is used, but a shunt film is used in the form of a two-layer film with these magnetoresistive films, which usually has a thickness of 10 ⁶ A / cm ² or more. The current of
The shunt film generates a bias magnetic field, and the magnetoresistive film generates a resistance change due to magnetoresistance.

A necessary property of the shunt film is that, in the two-layer film with the magnetoresistive effect film, the electric resistance value is set to an appropriate value for the magnetoresistive film so that a shunt occurs so as to optimize the bias magnetic field. That a reaction that degrades the magnetoresistive effect film does not occur in the manufacturing process of the magnetoresistive element, that it has excellent corrosion resistance, that the film is easy to form, and that there is little variation in electric resistance. And other conditions must be met.

Further, there is a soft bias type magnetoresistive head which uses a soft magnetic film as a bias magnetic field generating means and has a three-layer structure of a soft magnetic film / spacer metal film / magnetoresistive film. In this conventional example, USP 4,663,685
There is JP-A-3-116510.

However, in such a three-layer structure, it is meaningless if a current flows through the soft magnetic film, and the specific resistance of the spacer metal film is higher in that the current flowing through the magnetoresistive film is prevented from decreasing. Is good. Needless to say, the spacer metal film is also required to have the above-described reaction resistance, corrosion resistance, ease of film formation, non-uniformity in electric resistance, and the like.

[0007]

In the above prior art, considering the reaction with the magnetoresistive effect film, Japanese Patent Laid-Open No. 62-183
As described in No. 003, Ti reacts with the above-mentioned magnetoresistive film at 175 to 200 ° C., Mo, Ta, and Zr do not react up to about 350 ° C., but have poor corrosion resistance and high electric resistance, and Cr and its alloys The reaction temperature is low as in the case of, and the other conventional technologies show the same properties as the above materials except for Nb.

[0008] Nb has a high reaction initiation temperature with the magnetoresistive film, has excellent corrosion resistance, and is an excellent material as a shunt film. Normally, Nb produced by vapor deposition, sputtering, etc.
Although the electric resistance of the film is 25 to 35 μΩcm, there is a disadvantage that the electric resistance is apt to fluctuate due to the influence of residual oxygen and nitrogen in the film forming atmosphere.

Further, in order to improve the output of the magnetoresistive head, it is necessary to use a thinner magnetoresistive film, and the thickness of the shunt film must be reduced accordingly. The thickness of the magnetoresistive film is 5 to 50 nm, but the mean free path of the electrons in the metal film is about 30 nm.When the thickness of the magnetoresistive film reaches about 30 nm, the electrons collide with the surface of the film. And the phenomenon of being scattered becomes remarkable. Therefore, in a shunt film having a thickness of 30 nm or less, the variation in electric resistance becomes extremely remarkable. The control of the bias magnetic field requires the control of the film thickness and the electric resistance.However, in the case where the above-described Nb film is manufactured by a normal forming method, the variation of the electric resistance in this film thickness region is as large as 20 to 30%. Reach. The variation in the film thickness also overlaps with this, which greatly affects the control of the shunt with the magnetoresistive film, and it is extremely difficult to manufacture a shunt bias type magnetoresistive head having good characteristics without variation.

Also, in a soft bias type magnetic head, in order to prevent the sense current of the magnetoresistive film from shunting to the soft magnetic film, it is necessary to make the thickness of the spacer film as thin as possible to have high resistance. is there. However, in this case, as described above, there is a problem that the resistance of the spacer film varies.

In a conventional magnetoresistive head,
No consideration is given to reducing the variation in the electrical resistance of the shunt or spacer film when the magnetoresistive film is extremely thin as 5 to 30 nm, and a magnetoresistive head having good characteristics without variation and its manufacturing method There was no.

A first object of the present invention is to provide an Nb-based alloy metal material which is advantageous for use in a magnetoresistive head.

A second object of the present invention is to provide a shunt film most suitable for a high-output head having a thin magnetoresistive film, among shunt-bias magnetoresistive heads. A third object of the present invention is to provide a spacer metal layer suitable as a spacer metal layer for a soft bias type head.

In order to achieve the above object, in the magnetoresistive head of the present invention, the second metal is added to Nb without impairing the high corrosion resistance of Nb and the favorable reaction characteristics with the magnetoresistive film. An object of the present invention is to adjust the value of the electric resistance to solve the drawback of the prior art Nb.

Another object of the present invention is to provide a material suitable for a magnetoresistive head using a thin film.

[0016]

A magnetoresistive head according to the present invention comprises a first film exhibiting a magnetoresistive effect, Nb and Cr, Mo, Zr, W, Pt, Re,
It has a structure based on a two-layer film composed of at least one element selected from the group consisting of V, Hf, Ta, Rh, Ni, and Ru.

If the second film is a shunt film for applying a bias magnetic field to the first film, it becomes a shunt bias type head, and the third film exhibiting soft magnetism is a second film.
When laminated on the first film via this film, a soft bias type head is obtained.

The present invention provides an excellent material for a magnetoresistive head in addition to the above-mentioned applications. This is because Nb is a main component and Cr,
Mo, Zr, W, Pt, Re, V, Hf, Ta, Rh,
A thin film material for a magnetoresistive head including at least one additional element selected from the group consisting of Ni and Ru.
The addition amount of the additional element is 30 at. % Or less, and the additive element is Zr and 12 at. % Or less, and the additive element is V and 22 at. % Or less, the added element being Hf, and 27 at. % Or less, the additive element being W and 6 at. % Or less, and the added element is Ta at 27 at. % Or less, and the added element is Ru at 37 at. % Or less, and the added element is Rh at 27 at. % Or less, the added element is Re, and 17 at. % Or less, and the added element is Pt and 12 at. % Or less, the additive element being Cr and 6 at. % Or less, and the additive element is Mo, and 9 at. % Or less.

The content of the additional element which is particularly preferable as the material of the magnetoresistive head is 1 to 25 at.
%.

In the case of Zr, the content is 0.5 to 10 at.%.

In the case of V, the content is 3 to 20 at.%.

In the case of Hf, the content is 1 to 25 at.% W, and in the case of Hf, the content is 0.5 to 5 at.%.

In the case of Ta, the content is 3 to 25 at.%.

In the case of Ru, the content is 3 to 35 at.%.

In the case of Rh, the content is 3 to 25 at.%.

In the case of Re, the content is 3 to 15 at.%.

In the case of Pt, the content is 1 to 10 at.%.

In the case of Ni, the content is 3 to 25 at.%.

In the case of Cr, the content is 0.2 to 5 at.%.

In the case of Mo, the content is 3 to 8 at.%.

Is as follows.

[0032] In addition to the second element of the present invention, the addition of another element to enhance corrosion resistance and reaction resistance is also within the scope of the present invention.

[0033]

When a second element is added to Nb to form a shunt film, the shunt film must be in a range suitable for shunting with the magnetoresistive film. This value is 3 times the electric resistance of the magnetoresistive film.
Up to about twice is good. If the resistance is too high, the thickness of the shunt film must be increased, so that the dissipation of heat generated by the current deteriorates and the life of the element becomes very short. Further, the gap of the shield type magnetoresistive element cannot be reduced.

When an element is added to Nb, it generally becomes a solid solution when the amount of addition is small, but a two-phase structure consisting of a solid solution of an intermetallic compound and Nb peculiar to the alloy system except for an alloy system which is completely dissolved, An increase in electrical resistance, an increase in variation thereof, a deterioration in corrosion resistance, and the like occur. Therefore, it is desirable to be in a solid solution state. That is, since the two-phase structure changes greatly depending on the heat treatment conditions, the change in electric resistance is also remarkable.

With respect to the reaction with the magnetoresistive film, if the melting point of the alloy is lowered by the alloying of Nb, the reaction starting temperature is lowered. Therefore, the melting point of the Nb alloy needs to be about 2000 ° C. or more. If the temperature is lower than 2000 ° C., the reaction start temperature with the magnetoresistive film becomes 350 ° C. or lower, which is not preferable in terms of heat resistance. The range of the element addition amount of the Nb alloy that satisfies these conditions differs depending on the added element, and it is necessary to determine the electric resistance, the corrosion resistance, the reaction start temperature with the magnetoresistive film, and the like for each alloy system in detail.

By adding a second element to Nb, pure Nb
The electric resistance increases as compared with. Nb per unit amount
The amount of increase in the electrical resistance of the alloy depends on the type of the added element, but is generally linear in a region where the amount of addition is small as shown in FIG. 1, and deviates from the straight line as the amount of addition increases. As described above, the electrical resistance of the Nb film varies depending on the manufacturing method, but also greatly varies depending on the purity of Nb and the additional elements used. Here, the description is based on the case where a raw material having a purity of 99.9 to 99.999 wt.% Which is usually used industrially is used. Among the electric resistances shown in FIG. 1, the range of the electric resistance value that can be used for the shunt film is up to three times that of the magnetoresistive film as described above. In the above-described magnetoresistive effect film, when the film thickness is 5 to 30 nm, the electric resistance is 15 to 35.
The electrical resistance of the Nb alloy film as a shunt film is up to about 105 μΩcm, and within this range, it can be used as a shunt film.

Next, regarding the reaction with the magnetoresistive film, as a result of examining the reaction between the Nb alloy films having various melting points by alloying and the above-mentioned magnetoresistive film, as shown in FIG. The reaction initiation temperature is proportional to the melting point of the alloy, and if the required heating temperature in the process of manufacturing the magnetoresistive head is 300 ° C., the reaction initiation temperature must be 10-20% higher than this. If the temperature is 350 ° C., an alloy composition satisfying this must be selected. From the relationship shown in FIG. 3, the melting point of the Nb alloy satisfying the above reaction temperature of 350 ° C. is 2000
° C or higher.

Regarding the variation of the electric resistance, as shown in FIG. 3, the dependence of the electric resistance of the Nb alloy on the film thickness with respect to Nb is as follows.
The whole shifts to the high resistance side. In FIG. 3, the resistance value of the region where the electrical resistance of Nb does not depend on the film thickness is ρ ₀ , the resistance value of the region having the film thickness dependence is ρ _t , and the resistance value of the region of the Nb alloy which does not depend on the film thickness is ρ _t . if the resistance value of [rho ₀₁ thickness dependency of a region and _{ρ t1, (ρ t - ρ} 0) / ρ compared to ₀ (ρ _t1 -
ρ ₀₁ ) / ρ ₀₁ becomes smaller. Further, the variation Δρ ₀ of the electric resistance of the Nb film in the region having the thickness dependence and the Δρ _{01 of the} Nb alloy
Are smaller than Δρ ₀₁ .

In order to cope with the high density of the magnetic recording device,
It is necessary to reduce the thickness of the magnetoresistive effect film to increase the current, and as the thickness decreases, the shunt ratio between the shunt film and the magnetoresistive film varies due to the above-described causes. In order to reduce the variation, it is necessary to provide a power supply for energizing the elements with a circuit function for reducing the variation.
However, according to the present invention, the load on the power supply is greatly reduced.
At the same time, the reproduction error rate of the signal in recording and reproduction is reduced, so that the load on the error correction circuit is greatly reduced. Therefore, a magnetic storage device having a very low error rate is realized. With the above operation, the variation in the electric resistance of the Nb alloy film is reduced as compared with the Nb film, and the variation in the bias magnetic field intensity / output characteristic of the magnetoresistive element is reduced.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments.

Example 1 An Nb-Ti alloy obtained by adding 1 to 35 at.% Of Ti to Nb was prepared by a vacuum melting method, and a source for electron beam evaporation and a sputtering target were cut out from the alloy. These were used to deposit a thin film on a glass substrate by electron beam evaporation and sputtering.

FIG. 4 shows the dependence of the electric resistance of this thin film on the amount of Ti added. As typical examples, the case where the thickness is 100 nm in a region where the electric resistance does not depend on the film thickness and the case where the film thickness is 20 nm in a region where electrons are scattered by the film surface are shown. Here, the electric resistance is shown based on the electric resistance of Nb. Regardless of the film thickness, the electrical resistance of the Nb-Ti alloy film does not show a remarkable increase up to 1 at.% Of Ti content, becomes evident when it exceeds 1 at.%, And increases almost linearly up to 25 at.%. However, when it exceeds 25 at.%, A sharp increase is seen.

As described above, the resistance of the metal film used for the shunt film of the magnetoresistive element is smaller than the resistance of the magnetoresistive film.
1 to 3 times is desirable, and since the resistance of the magnetoresistive film usually manufactured is 15 to 30 μΩcm, Nb for a shunt film is desirable.
The upper limit of the resistance of the alloy is about 90 μΩcm, and the preferable addition amount of Ti for the shunt film is 25 at.% Or less.

Considering the amount of Ti to be added in a region where the effect of (ρ _t1 -ρ ₀₁ ) / ρ ₀₁ is remarkable, the amount of Ti added is
5-25at.% Is more effective. The reason that the resistance does not increase easily when the Ti addition amount is low is that the Ti reacts with the residual gas such as oxygen in the atmosphere during the film formation process such as evaporation to reduce the amount of gas impurity gas mixed into Nb. It is estimated to be.

When the Ti content is in the range of 1 to 5 at.%, The resistance of the Nb alloy film does not increase remarkably, but the variation of the resistance is about 1/3 to 1/1 compared to the Nb film due to the getter effect of Ti. Reduce to 2. Therefore, when Ti is added, there is an effect of reducing the variation in electric resistance of the shunt film due to the getter effect.

On the other hand, as shown in FIG. 5, the reaction with the Ni-19at.% Fe alloy film, which is a magnetoresistive film, and the Nb-Ti alloy film was examined by heat treatment in vacuum. 28 added
It becomes 350 ° C near at.% and 300 ° C or less near 30at.%. When the maximum heat treatment temperature in the head manufacturing step exceeds 300 ° C., the addition of 30 at.% Or more of Ti is not practical as a head material.

After the above examination, Nb, Nb-1at.% Ti,
Nb-5at.% Ti, Nb-10at.% Ti, Nb-20at.% Ti, Nb-25at.% T
i, Nb-39at.% Ti film is used for the shunt film, and Ni-19at.% Fe, Ni-50at.% Co, Ni-10at.% Fe-9at.% Co are used as the magnetoresistive film.
Was used to produce a magnetoresistive head.

As a result, the variation of the bias magnetic field strength of the head due to the variation of the electric resistance of the shunt film is compared with the vertical asymmetry of the waveform of the head output. Also varies from 1/3 to 1/2
Decreased to below. A similar study was conducted on Ni-Fe containing 7 to 27 at.% Fe.
Magnetoresistive film, Ni-Co magnetoresistive film containing 30 to 50 at.% Co, Fe to 3 to 18 at.%, Co to 3 to 15 at.%, Balance Ni
When a head was fabricated using a Ni-Fe-Co magnetoresistive film and evaluated, it was confirmed that variations in the head characteristics were reduced due to the effect of reducing the electrical resistance variation of the shunt film.

Example 2 In the same manner as in Example 1, the electrical resistance of an Nb-Zr alloy obtained by adding 0.5 to 35 at.% Of Zr to Nb and its variation were examined.

As shown in FIG. 6, in the case of the Nb-Zr alloy film, the Zr content does not show a remarkable increase up to 0.5 at.%, And when the Zr content is 0.5 at.% Or more, the increase becomes clear, and up to 10 at. It increases almost linearly, and shows a sharp increase when it exceeds 10 at.%. This rapid increase in resistance is considered to be due to the formation of a two-phase structure, but as described above, the resistance of the metal film used for the shunt film of the magnetoresistive element is one of the resistance of the magnetoresistive film.
If the upper limit of the resistance of the Nb alloy that can be used for the shunt film is about 90 μΩcm, Zr that can be used for the shunt film
The addition amount is 0.5 to 10 at.%.

Considering the addition amount of Zr in a region where the effect of (ρ _t1 −ρ ₀₁ ) / ρ ₀₁ is remarkable, the addition amount of Zr is as follows.
2.5-10at.% Is more effective. The reason that the increase in resistance is small when the amount of Zr added is small is that the amount of impurity gas mixed with Nb by reacting with Zr in the atmosphere and remaining gas such as oxygen in the process of forming a film such as evaporation is the same as in the case of Ti. Presumed to be due to the reduced getter effect.

When the Zr content is in the range of 0.5 to 2.5 at.%, The increase in resistance of the Nb alloy film is not remarkable, but the variation in resistance is about 1/3 to 1 compared to the Nb film due to the getter effect of Zr. / 2. Therefore, even when Zr is added, there is an effect of reducing the variation in electric resistance of the shunt film due to the getter effect.

On the other hand, the magnetoresistive film Ni-19at.% Fe
The reaction between the alloy film and the Nb-Zr alloy film was examined by heat treatment in a vacuum, and the reaction temperature was maintained at 350 ° C. or higher without any significant change even when the amount of Zr added was increased. However, an Nb-Zr alloy containing a large amount of Zr, for example, about 12 at.% Zr or more, is not practical as a head material because the corrosion resistance is greatly reduced.

After the above examination, Nb, Nb-0.5at.% Z
r, Nb-2.5at.% Zr, Nb-5at.% Zr, Nb-7.5at.% Zr, Nb-10a
Using t.% Zr for the shunt film, Ni-19a as the magnetoresistive film
A magnetoresistive head was manufactured using t.% Fe, Ni-50at.% Co, and Ni-10at.% Fe-9at.% Co. As a result, variations in the bias magnetic field strength of the head due to variations in the electrical resistance of the shunt film are different for the Nb-Zr alloy than for Nb, as compared with the vertical asymmetry of the head output waveform. It decreased from 1/3 to less than 1/2.

A similar study was conducted on a Ni-Fe magnetoresistive film containing 7 to 27 at.% Fe, a Ni-Co magnetoresistive film containing 30 to 50 at.% Co, 3 to 18 at.% Fe, and 3 ~ 15at.%, Ni consisting of residual Ni
When a head was fabricated using the -Fe-Co magnetoresistive film and evaluated, it was confirmed that the variation in the head characteristics was reduced due to the effect of reducing the electrical resistance variation of the shunt film.

Example 3 In the same manner as in Examples 1 and 2, Nb was added at 1 to 35 at.
As a result of examining the electrical resistance and variation of the Nb-V alloy to which V was added and examining the amount of V that can be used for the shunt film, the range of 3 to 20 at.% Is effective for V (Fig. 6). .

Also in the case of V addition, the resistance greatly increases at 20 at.% Or more. The reaction between the Ni-19 at.% Fe alloy film and the Nb-V alloy film was examined by heat treatment in vacuum. The reaction temperature is
It decreases with an increase in the added amount of V, and becomes 350 ° C. or less near Nb-22at.% V. Therefore, an Nb-V alloy of 22 at.% V or more depends on the maximum heat treatment temperature in the head manufacturing process, but if it exceeds 300 ° C., it is not practical as a head material.

Although the change in the resistance of the Nb film is small when V is added at 3 at.% Or less, the large effect of reducing the variation in the electric resistance of the shunt film does not appear unless 3 at.% Or more is added. In the case of V, the reduction in resistance variation in the range where the addition amount is small seems to be mainly due to the getter effect of V.
Since the getter effect of V is weaker than that of, it seems necessary to slightly increase the amount of addition. However, the variation in resistance when adding 3 at.% Or more is similar to that of adding Ti and Zr.
It was about 1/3 to 1/2 compared to the Nb film.

After the above examination, similarly to the case of adding Ti and Zr, an Nb-V alloy film was used as a shunt film, and Ni-19at.% Fe, Ni-50at.% Co, Ni- As a result of fabricating a magnetoresistive head using 10at.% Fe-9at.% Co, the variation in the bias magnetic field strength of the head due to the variation in the electrical resistance of the shunt film is compared with the vertical asymmetry of the head output waveform. , And Nb films decreased from 1/3 to 1/2 or less. Similar studies were conducted on Ni-Fe magnetoresistive films containing 7 to 27 at.% Fe, Ni-Co magnetoresistive films containing 30 to 50 at.% Co, F
e to 3 to 18 at.%, Co to 3 to 15 at.%, Ni-Fe-C consisting of residual Ni
o When a head was fabricated using a magnetoresistive film and evaluated, it was confirmed that the variation in head characteristics was also reduced due to the effect of reducing the variation in electrical resistance of the shunt film.

Example 4 In the same manner as in Examples 1 and 2, 0.5 to 35 at.
% Hf added, the electrical resistance of the Nb-Hf alloy and its variation were examined, and as a result of examining the Hf addition amount that can be used for the shunt film, the range of 1 to 25 at.% Is effective for Hf (FIG. 6). ).

Also in the case of adding Hf, the resistance greatly increases when the content becomes 25 at.% Or more. Considering the addition amount of Hf in a region where the effect of (ρ _t1 −ρ ₀₁ ) / ρ ₀₁ is remarkable, the addition amount of Hf is more effective from 5 to 25 at.%.

Further, when the reaction between the Ni-19at.% Fe alloy film and the Nb-Hf alloy film was examined by heat treatment in vacuum, the reaction temperature was Nb-27at.% As the addition amount of Hf was increased. 350 ° C near% Hf
It becomes below. Therefore, an Nb-Hf alloy of 27 at.% Hf or more is not practical as a head material when the maximum heat treatment temperature in the head manufacturing step exceeds 300 ° C.

Although the change in the resistance of the Nb film is small with the addition of Hf of 1 at.% Or less, the effect of reducing the variation in the electric resistance of the shunt film is not seen unless it is added at 1 at.% Or more. The variation of resistance when 1at.% Or more is added is similar to that of Ti and Zr addition.
It is about 1/3 to 1/2 compared to the Nb film.

After the above examination, as in the case of adding Ti and Zr, an Nb-Hf alloy film was used for the shunt film, and Ni-19at.% Fe, Ni-50at.% Co, Ni- 10at.% Fe-9at.% Co
As a result of fabricating a magnetoresistive head using, the variation in the bias magnetic field strength of the head due to the variation in the electrical resistance of the shunt film is compared with the vertical asymmetry of the head output waveform, and compared with the Nb film. Both decreased from 1/3 to less than 1/2. Similar studies were conducted on Ni-Fe magnetoresistive films containing 7 to 27 at.% Fe, Ni-Co magnetoresistive films containing 30 to 50 at.% Co, 3 to 18 at.% Fe, and 3 to 15 at.Co. %, Ni consisting of residual Ni
When a head was fabricated using the -Fe-Co magnetoresistive film and evaluated, it was confirmed that the variation in the head characteristics was also reduced due to the effect of reducing the electrical resistance variation of the shunt film.

Example 5 In the same manner as in Examples 1 and 2, 0.5 to 35 at.
The electrical resistance of the Nb-W alloy to which W was added and the variation thereof were examined. In the case of the Nb-W alloy film, the W amount does not show a remarkable increase up to 0.5 at.%, And the increase becomes clear when the W amount is 0.5 at.% Or more, and increases almost linearly up to 10 at. %, A sharp increase is seen (Fig. 6).

As described above, the resistance of the metal film used for the shunt film of the magnetoresistive element is smaller than the resistance of the magnetoresistive film.
If the upper limit of the resistance of the Nb alloy that can be used for the shunt film is about 90 μΩcm, the amount of W that can be used for the shunt film is 0.5 to 10 at.%.

Considering the addition amount of W in a region where the effect of (ρ _t1 −ρ ₀₁ ) / ρ ₀₁ is remarkable, the addition amount of W is 2.
5-10at.% Is considered more effective.

In the case of W, Ni-
Examination of the reaction with the 19at.% Fe alloy film and the corrosion resistance revealed that the reaction temperature was maintained at 350 ° C or higher without any significant change at the added amount of 10at.%, But the corrosion resistance was significantly reduced by the addition of W. I do. From the viewpoint of the corrosion resistance, it was found that an Nb-W alloy of 6 at.% Or more was not practical as a head material.

Therefore, in the case of W,
The addition amount of 0.5 to 5 at.% Is an appropriate amount, and the variation in the resistance of the Nb-W alloy film in this range is reduced to about 1/3 to 1/2 as compared with the Nb film. Therefore, it is considered that the addition of W also has the effect of reducing the variation in the electric resistance of the shunt film.

After the above examination, as in the case of adding Ti and Zr, an Nb-W alloy film was used for the shunt film, and Ni-19at.% Fe, Ni-50at.% Co, Ni -10at.% Fe-9at.% C
As a result of fabricating a magnetoresistive head using o, variations in the bias magnetic field strength of the head due to variations in the electrical resistance of the shunt film are compared with the vertical asymmetry of the head output waveform, compared to the Nb film. In each case, it decreased from 1/3 to less than 1/2.

A similar study was conducted on a Ni-Fe magnetoresistive film containing 7 to 27 at.% Fe, a Ni-Co magnetoresistive film containing 30 to 50 at.% Co, 3 to 18 at.% Fe, and 3 ~ 15at.%, Ni consisting of residual Ni
When a head was fabricated using the -Fe-Co magnetoresistive film and evaluated, it was confirmed that the variation in the head characteristics was also reduced due to the effect of reducing the electrical resistance variation of the shunt film.

Example 6 In the same manner as in Example 1 and Example 2, 0.5 to 35 at.
As a result of examining the electrical resistance of the Nb-Ta alloy to which Ta is added and the variation thereof, and examining the amount of Ta that can be used for the shunt film, the range of 3 to 25 at.% Is effective for Ta.

In the case of adding Ta, the resistance greatly increases at 25 at.% Or more (FIG. 6), and the reaction temperature with the Ni-19 at.% Fe alloy film becomes Nb-27 at. It becomes 350 ° C or less near Ta. Therefore, an Nb—Ta alloy of 27 at.% Ta or more is not practical as a head material when the maximum heat treatment temperature in the head manufacturing process exceeds 300 ° C.

The effect of reducing the variation in electric resistance of the shunt film by adding Ta in the range of 3 to 25 at.% Is about 1/3 to 1/2 as compared with the Nb film as in the case of adding Ti and Zr. It was confirmed. After the above examination, Nb-3 ~
A magnetoresistive head using a 25at.% Ta alloy film for the shunt film and using Ni-19at.% Fe, Ni-50at.% Co, Ni-10at.% Fe-9at.% Co as the magnetoresistive film As a result, the variation in the bias magnetic field strength of the head due to the variation in the electric resistance of the shunt film was compared with the Nb film in comparison with the vertical asymmetry of the head output waveform. Decreased to 2 or less.

A similar study was conducted on a Ni-Fe magnetoresistive film containing 7 to 27 at.% Fe, a Ni-Co magnetoresistive film containing 30 to 50 at.% Co, 3 to 18 at.% Fe, and 3 ~ 15at.%, Ni consisting of residual Ni
When a head was fabricated using a -Fe-Co magnetoresistive film and evaluated, it was confirmed that the variation in the head characteristics was also reduced due to the effect of reducing the electrical resistance variation of the shunt film.

Example 7 In the same manner as in the above-described example, the electrical resistance of Nb-Ru alloy in which 0.5 to 35 at.% Of Ru was added to Nb and its variation were examined, and the amount of Ru that can be used for the shunt film was examined. did. As a result, in the case of Ru, even if Ru is added to Nb up to 35 at.%, The resistance of Nb increases linearly, and the resistance value does not exceed the resistance value of the Nb alloy usable for the shunt film of about 90 μΩcm. It is in.
Therefore, when the addition amount was further increased and Ru was added up to 40 at% and the change in the resistance of Nb was examined, it was found that the resistance increased significantly above 35 at.% (FIG. 6).

In view of these resistance changes, the amount of Ru that can be used for the shunt film is 3 to 35 at.%. Next, Ni-19a
The reaction between the t.% Fe alloy film and the Nb-Ru alloy film and the corrosion resistance of the Nb-Ru alloy film were investigated.The reaction temperature fell below 350 ° C near Nb-37at.% Ru due to the increase in the amount of Ru added. And therefore 37
Nb-Ru alloys of at.% Ru or more are not practical as head materials when the maximum heat treatment temperature in the head manufacturing process exceeds 300 ° C.

On the other hand, there is no problem with respect to the corrosion resistance of the Nb—Ru alloy film. Rather, the addition of Ru improves the corrosion resistance of the Nb film, resulting in a very favorable result.

The effect of reducing the variation in electric resistance of the shunt film by adding Ru in the range of 3 to 35 at.% Is about 1/3 to 1/2 as compared with the Nb film as in the case of adding Ti and Zr. It was confirmed. When Ru is added at 3 at.% Or less, although the resistance change is small, the effect of reducing variation is not so large, so 3 at.%
The above Ru addition is effective.

After the above examination, as in the case of adding Ti and Zr, an Nb-3 to 25 at.
Ni-19at.% Fe, Ni-50at.% Co, Ni-10at.
As a result of fabricating a magnetoresistive head using% Fe-9at.% Co, the variation in the bias magnetic field strength of the head due to the variation in the electrical resistance of the shunt film was compared with the vertical asymmetry of the head output waveform. In each case, 1 /
It decreased from 3 to less than 1/2. Similar considerations for Fe 7-27at.%
Ni-Fe magneto-resistive film containing 30 to 50 at.% Co, Ni-Co magneto-resistive effect film containing 3 to 18 at.% Fe, 3 to 15 at.% Co, residual Ni
When a head was fabricated using a Ni-Fe-Co magnetoresistive film made of and evaluated, it was confirmed that the variation in head characteristics was also reduced due to the effect of reducing the variation in electrical resistance of the shunt film. Another effect of the addition of Ru is an improvement in the corrosion resistance of the Nb film. The increase in the Nb film thickness due to oxidation at a temperature of 90 ° C., RH 95% and 200 hours was less than 1/10 compared to Nb. This indicates that Ru has a significant effect on the corrosion resistance of Nb.

Example 8 Nb was added to Nb in an amount of 0.5 to 35 at.
The electrical resistance of the Nb-Rh alloy to which Rh was added and its variation were examined, and the amount of Rh that can be used for the shunt film was examined. As a result, the range of 3 to 25 at.

Also in the case of adding Rh, the resistance greatly increases at 25 at.% Or more (FIG. 6), and the reaction temperature with the Ni-19 at.% Fe alloy film is set to Nb-27 at. It becomes 350 ° C or less near Rh. Therefore, an Nb-Rh alloy of 27 at.% Rh or more is not practical as a head material when the maximum heat treatment temperature in the head manufacturing step exceeds 300 ° C.

On the other hand, the corrosion resistance of the Nb-Rh alloy film has no problem in the range of 3 to 25 at.% As in the case of the Nb-Ru alloy film. Rather, the corrosion resistance of the Nb film is improved by the addition of Rh. Very good results.

The effect of the addition of Rh in the range of 3 to 25 at.
It was confirmed that the amount was about 1/3 to 1/2 as compared with the Nb film as in the case of addition. With the addition of 3 at.% Or less of Rh, although the resistance change is small, the effect of reducing variation is not so large,
The addition of 3 at.% Or more of Rh is effective.

After the above examination, an Nb-3 to 25 at.% Rh alloy film was used for the shunt film as in the case of adding Ti and Zr, and Ni-19 at.% Fe and Ni-50 at. Co, Ni-10at.% Fe-
As a result of fabricating a magnetoresistive head using 9at.% Co, the variation in the bias magnetic field strength of the head due to the variation in the electrical resistance of the shunt film was compared with the Nb film compared with the vertical asymmetry of the head output waveform. 1/3 compared to
From less than 1/2. Similar studies were conducted on Ni-Fe magnetoresistive films containing 7 to 27 at.% Fe, Ni-Co magnetoresistive films containing 30 to 50 at.% Co, 3 to 18 at.% Fe, and 3 to 15 at.Co. %, A head was fabricated using a Ni-Fe-Co magnetoresistive film composed of the remaining Ni, and evaluated. As a result, it was confirmed that the variation in the head characteristics was also reduced due to the effect of reducing the variation in the electric resistance of the shunt film.

Another effect of the addition of Rh is an improvement in the corrosion resistance of the Nb film. The increase in the Nb film thickness due to oxidation at a temperature of 90 ° C., RH 95% and 200 hours was less than 1/10 compared to Nb. This indicates that Rh has a significant effect on the corrosion resistance of Nb.

Example 9 Nb was added to Nb in an amount of 0.5 to 35 at.
As a result of examining the electric resistance of the Nb-Re alloy to which Re is added and the variation thereof, and examining the amount of Re added that can be used for the shunt film, the range of 3 to 15 at.% Is effective for Re.

Also in the case of adding Re, the resistance greatly increases at 15 at.% Or more (FIG. 6), and the reaction temperature with the Ni-19 at.% Fe alloy film becomes Nb-17 at. It becomes 350 ° C or less near Rh.

Therefore, an Nb—Re alloy of 17 at.% Re or more is not practical as a head material when the maximum heat treatment temperature in the head manufacturing step exceeds 300 ° C.

On the other hand, the corrosion resistance of the Nb-Re alloy film is not particularly large in the range of 3 to 15 at.%, And the corrosion resistance of the Nb film is slightly improved by adding Re.

The effect of reducing the variation in electric resistance of the shunt film by adding Re in the range of 3 to 15 at.
It was confirmed that the amount was about 1/3 to 1/2 as compared with the Nb film as in the case of addition. With less than 3at.% Re addition, although the resistance change is small, the effect of reducing variation is not so large,
Re addition of 3 at.% Or more is effective.

After the above examination, a Ni-Fe magnetic film containing 7 to 27 at.% Fe as a magnetoresistive film using an Nb-3 to 15 at.% Re alloy film as a shunt film as in the case of adding Ti and Zr. Resistive film, Co
Ni-Co magnetoresistive film containing 30 to 50 at.%, Fe 3 to 18 at.
%, Co was 3 to 15 at.%, And the head was fabricated using a Ni-Fe-Co magnetoresistive film consisting of the remaining Ni. Was confirmed.

Example 10 Nb was added to Nb in an amount of 0.5 to 35 at.
As a result of examining the electric resistance of the Nb-Pt alloy to which Pt is added and the variation thereof, and examining the amount of Pt that can be used for the shunt film, the range of 1 to 10 at.% Is effective for Pt.

Also in the case of adding Pt, the resistance greatly increases at 10 at.% Or more (FIG. 6), and the reaction temperature with the Ni-19 at.% Fe alloy film is increased by Nb-12 at. It becomes 350 ° C or less near Pt.

Therefore, an Nb—Re alloy of 12 at.% Pt or more is not practical as a head material when the maximum heat treatment temperature in the head manufacturing process exceeds 300 ° C.

On the other hand, the corrosion resistance of the Nb-Pt alloy film is not particularly large in the range of 1 to 10 at.%, And the corrosion resistance of the Nb film is slightly improved by adding Pt. this
The effect of reducing the electrical resistance variation of the shunt film by adding Pt in the range of 1 to 10 at.% Is similar to that of adding Ti and Zr.
It was confirmed to be about 1/3 to 1/2 compared to the Nb film.

When the Pt content is 1 at.% Or less, although the resistance change is small, the effect of reducing the variation is not so large.
Pt addition of 1 at.% Or more is effective.

After the above examination, the Nb-1 to 10 at.% Pt alloy film was used for the shunt film as in the case of adding Ti and Zr.
Ni-Fe magnetoresistive film containing 7 to 27 at.% Fe, Ni-Co magnetoresistive film containing 30 to 50 at.% Co, Fe 3 to 3
Using a Ni-Fe-Co magnetoresistive film composed of 18 at.%, Co at 3 to 15 at.%, And the remaining Ni, a head was fabricated and evaluated. A reduction in variation was confirmed.

Embodiment 11 Nb was added to Nb in the same manner as in the above-described embodiment by 0.5 to 35 at.
The electrical resistance of Ni-added Nb-Ni alloy and its variation were examined, and the amount of Ni that can be used for the shunt film was examined. As a result, in the case of Ni, the range of 3 to 25 at.% Was effective.

In the case of adding Ni, the resistance greatly increases at 25 at.% Or more (FIG. 6), but the reaction temperature with the Ni-19 at. Is almost the same as the reaction temperature alone.

The corrosion resistance of the Nb—Ni alloy film is also 3 to
In the range of 25 at.%, There is no problem at all, but rather, the corrosion resistance of the Nb film is improved by adding Ni. Therefore, Ni
In the case of addition, a large increase in resistance at 25 at.% Or more determines the effective addition amount.

The effect of reducing the variation in electric resistance of the shunt film by adding Ni in the range of 3 to 25 at.% Is about 1/3 to 1/2 as compared with the Nb film as in the above-described embodiment. I confirmed that it would be. Addition of 3 at.% Or less is effective because addition of Ni at 3 at.% Or less has a small resistance change but does not have a great effect of reducing variation.

After the above examination, the Nb-3 to 25 at.% Ni alloy film was used for the shunt film in the same manner as in the case of adding Ti and Zr.
Ni-Fe magnetoresistive film containing 7 to 27 at.% Fe, Ni-Co magnetoresistive film containing 30 to 50 at.% Co, Fe 3 to 3
Using a Ni-Fe-Co magnetoresistive film composed of 18 at.%, Co at 3 to 15 at.%, And the remaining Ni, a head was fabricated and evaluated. A reduction in variation was confirmed.

Embodiment 12 Nb is added to Nb in the same manner as in the above-described embodiment by 0.1 to 35 at.%.
Investigating the electrical resistance and variation of the Nb-Cr alloy to which Cr was added, and examining the amount of Cr that can be used for the shunt film, it was found that Cr was effective in a narrow range of 0.2 to 5 at.%. Was.

This is because in the case of adding Cr, the resistance of the Nb film increases significantly due to the addition, and the resistance further increases sharply at 7 at.% Or more (FIG. 6). The reason for this is that the reaction temperature with the film greatly decreases with respect to the addition of Cr, and as the amount of addition increases, the temperature becomes already 350 ° C. or less near Nb-6at.% Cr. Therefore, an Nb—Cr alloy of 6 at.% Cr or more is not practical as a head material when the maximum heat treatment temperature in the head manufacturing process exceeds 300 ° C.

The corrosion resistance of the Nb—Cr alloy film does not cause any problem even if it is added at 10 at.% Or more.

The effect of reducing the variation in electric resistance of the shunt film by adding Cr in the range of 0.2 to 5 at.% Is about 1/3 to 1/2 as compared with the Nb film as in the above-described embodiment. I confirmed that it would be. However, the addition of 0.2 at.% Or less of Cr is effective because the variation in resistance is small but the variation reduction effect is not so large when adding Cr of 0.2 at.% Or less.

After the above examination, the Nb-0.2 to 5 at.% Cr alloy film was used for the shunt film as in the case of the addition of Ti and Zr, and the Ni- containing 7 to 27 at. Fe magnetoresistive film, Ni-Co magnetoresistive film containing 30 to 50 at.% Co, Fe
3-18at.%, Co 3-15at.%, Ni-Fe-Co
When a head was manufactured using the magnetoresistive effect film and evaluated, it was confirmed that the variation in the head characteristics was also reduced due to the effect of reducing the variation in the electrical resistance of the shunt film.

Example 13 Nb was added to Nb in the same manner as in the above-mentioned Example by 0.5 to 35 at.
As a result of examining the electric resistance and variation of the Nb-Mo alloy to which Mo was added, and examining the amount of Mo that can be used for the shunt film, it is effective to add a relatively narrow range of 3 to 8 at.% For Mo. I found it.

Also in the case of adding Mo, the resistance of the Nb film increases greatly due to the addition, and the resistance sharply increases at 10 at.% Or more (FIG. 6).
This is because the corrosion resistance is significantly reduced by the addition of Mo, and Nb-Mo alloys of 9 at.% Or more are not practical as shunt films from the viewpoint of corrosion resistance.

There is no particular problem regarding the reaction temperature with the Ni-19at.% Fe alloy film, and a relatively large amount of Mo is added (about 15 at.%).
But it is kept above 350 ° C.

The effect of reducing the variation in electric resistance of the shunt film by adding Mo in the range of 3 to 8 at.% Is about 1/3 to 1/2 as compared with the Nb film as in the above-described embodiment. It was confirmed. With less than 3 at.% Mo addition, although the resistance change is small, the effect of reducing variation is not so large,
Mo addition of 3 at.% Or more is effective.

After the above examination, the Nb-3 to 8 at.% Mo alloy film was used for the shunt film as in the case of adding Ti and Zr.
Ni-Fe magnetoresistive film containing 7 to 27 at.% Fe, Ni-Co magnetoresistive film containing 30 to 50 at.% Co, Fe 3 to 3
Using a Ni-Fe-Co magnetoresistive film consisting of 18 at.%, Co at 3 to 15 at.%, And the remaining Ni, the head was fabricated and evaluated. A reduction in variation was confirmed.

Embodiment 14 FIG. 7 is a cross-sectional view of a magnetoresistive head according to an embodiment of the present invention as viewed from the side facing the medium.

In the magneto-resistance effect type magnetic head 1 according to this embodiment, the shunt film 8 and the magneto-resistance effect film 6 are
The Nb alloy film, NiFe alloy film, NiCo alloy film, or Ni described in the first to thirteenth embodiments.
An FeCo alloy film was used. A method of manufacturing the magneto-resistance effect type magnetic head 1 will be described. First, on a substrate 2 of an appropriate thickness made of a ceramic insulator such as zirconia, an insulating layer 3 made of alumina or the like for flattening is interposed. Then, the lower magnetic shield layer 4 was laminated in a thickness of 1 to 3 μm, processed into a predetermined shape by photolithography and dry etching, and then an insulating layer 5 made of alumina for forming a gap layer was laminated in a thickness of 0.05 to 0.4 μm. All were laminated by a sputtering method. On top of this, the magnetoresistive effect film 6,
Antiferromagnetic film 7 for magnetic domain stabilization and Nb alloy shunt film 8
Is continuously formed using a vapor deposition method and a sputtering method, processed into a predetermined shape by photolithography and dry etching, and then Au or C of the electrode film 9 is formed.
u, AuCu alloy or the like is laminated by a sputtering method. Here, in order to remove the natural oxide film formed on the surface of the shunt film, it is necessary to slightly perform sputter etching before lamination. After laminating the electrode films, the electrodes 9 were formed by photolithography and dry etching or wet etching into a predetermined electrode shape for determining the track width.

Here, the thicknesses of the magnetoresistive film 6, the magnetic domain stabilizing antiferromagnetic film 7, the Nb alloy shunt film 8, and the electrode film are 5 to 50 nm, up to 40 nm, and 5 to 150 n, respectively.
m, 50 to 500 nm. Further, an FeMnRu alloy film or a FeMn alloy film was used as the magnetic domain stabilizing antiferromagnetic film 7. After forming the electrode 9 in this way, the soft magnetic bias film 10 for enhancing the bias magnetic field is
A 50 nm layer was laminated and processed into the same shape as the magnetoresistive film by the same method. Further, an insulating layer 11 made of alumina for forming an upper gap layer is laminated by a sputtering method of 0.05 to 0.4 μm, and finally, an upper magnetic shield layer 12 is laminated to a thickness of 1 to 3 μm, processed into a predetermined shape, and protected. The production of the magnetoresistive head 1 was completed by laminating the insulating layer 13 as a film.

When the magnetoresistive head 1 is actually used, a recording magnetic head is laminated above or below (before laminating and forming the head) and used in the form of a composite head. I do. FIG. 8 shows a sectional view of the composite head. A recording magnetic head 8 on the magnetoresistive head 1
3 to form a composite head capable of recording and reproduction. 81 and 83 are magnetic cores of the recording magnetic head. The configuration of the magnetoresistive head is the same as in FIG.

In the embodiment shown in FIG.
The upper magnetic domain stabilizing antiferromagnetic film 7 is formed on the entire surface of the magnetoresistive effect film. It is more preferable to provide them on both sides. FIG. 9 shows a sectional view of the head in this case. Other parts and their numbers are shown in FIG.
Is the same as

When the signal magnetic flux from the recording medium is read by the magnetoresistive head 1, the soft magnetic bias film 10 / Nb alloy shunt film 8 / the antiferromagnetic film 7 for stabilizing the magnetic domain / the magnetoresistive film 6 is passed through the electrode 9. Is applied to the magnetoresistive film 6 so that a proper bias magnetic field is applied to the magnetoresistive film 6. The sense current is shunted to each film in inverse proportion to the resistance, but the magnetic field created by the current flowing in the films other than the magnetoresistive film is applied as a bias magnetic field. The magnetic field including the magnetic field returning to the magnetoresistive film 6 via the soft magnetic bias film 10 is also applied as a bias magnetic field. Therefore, the magnetoresistive film 6 is brought into the optimum bias state by the combined magnetic field. It is necessary to adjust the sense current and the thickness of each film in consideration of the output.

In the optimum bias state, the magnetization in the magnetoresistive film forms an angle of approximately 45 degrees with respect to the direction of the sense current. When a signal magnetic flux enters the medium in this state, the magnetic flux depends on the direction of the signal magnetic flux. The angle of the magnetization of the resistance effect film with respect to the sense current also increases or decreases from 45 degrees. Correspondingly, the resistance of the magnetoresistive film decreases and increases, so that this resistance change can be detected as a voltage change from the electrode and a signal can be read. In such an optimum bias state, the output of the head is the largest, and the symmetry of the outputs having different polarities is the best. Conversely, if the optimum bias state is broken, the output is reduced, the symmetry is also deteriorated, and the head characteristics are deteriorated, making it impossible to actually use the head.

When the heads are mass-produced, it is inevitable that the bias state between the heads varies from the optimum state with respect to a fixed sense current value. However, if this variation increases, the yield decreases. The cause of the variation is mainly due to the variation in the bias magnetic field caused by the variation in the resistance of the shunt film, the soft magnetic bias film, and the antiferromagnetic film for stabilizing the magnetic domain. The influence of resistance variation is the largest. In this regard, in the present embodiment, as described above, since the Nb alloy shunt film having a very small variation in resistance is used for the shunt film, the variation in the asymmetry of the head output is smaller than that in the case where the Nb shunt film is used. Decreased to about 1/3 to 1/2. In the present embodiment, Barkhausen noise, which is known to be generated in the magnetoresistive head, is almost completely suppressed by the action of the magnetic domain stabilizing antiferromagnetic film stacked on the magnetoresistive effect. Was completed. This embodiment has the effects described above.

In this embodiment, the soft magnetic bias film 10 is directly laminated on the Nb alloy shunt film 8 for enhancing the bias magnetic field. Instead of directly laminating the soft magnetic bias film 10, an insulating layer is provided between the soft magnetic bias film 10 and the shunt film. The effect does not change even if it is carried out via a hard magnetic bias film, and a hard magnetic bias film may be used instead of the soft magnetic bias film. If the bias is sufficient, it is not necessary to use a magnetic film for bias enhancement. Further, although the antiferromagnetic film 7 is continuously laminated on the magnetoresistive film for stabilizing the magnetic domain of the magnetoresistive film 6, a hard magnetic film may be used instead. However, in any of these cases, N
Approximately 1/3 or more because b alloy shunt film is used
A half head output variation reduction effect is obtained.

Embodiment 15 The magnetoresistive head according to the present embodiment is the same as the magnetoresistive head 1 of Embodiment 14 shown in FIG. 7 except that the magnetoresistive film 6 and the antiferromagnetic film 7 for stabilizing the magnetic domains are used. , A Nb alloy shunt film 8, an electrode film 9, and a soft magnetic bias film 10 in that order. The Nb alloy shunt film 8 and the soft magnetic bias film 10 , And finally, the electrode 9 is formed. However, other structures are exactly the same as the structure of the fourteenth embodiment, and the manufacturing methods are all the same. Also, in this embodiment, the Nb alloy film, NiFe alloy film, NiCo alloy film, or NiFeCo alloy film described in Embodiments 1 to 13 are used as the shunt film and the magnetoresistance effect film. Not even. Therefore, the operation, operation, and effects of the magnetoresistive head according to the present embodiment are exactly the same as those of the magnetoresistive head 1 according to the fourteenth embodiment.
When the magnetoresistive effect type magnetic head according to this embodiment is actually used, a recording magnetic head is stacked above or below (before stacking and forming the head) a composite head. Must be used in the form of

Also in this embodiment, a hard magnetic bias film may be used in place of the soft magnetic bias film, and a hard magnetic bias film may be used in place of the antiferromagnetic film for stabilizing the magnetic domain of the magnetoresistive film. A membrane may be used. However, in any of these cases, since the Nb alloy shunt film is used, a similar head output variation reduction effect of about 1/3 to 1/2 can be obtained.

Embodiment 16 The magnetoresistive head according to the present embodiment is the same as that of Embodiment 1.
4 in the magneto-resistance effect type magnetic head 1 shown in FIG. 7, a magneto-resistance effect film 6, a magnetic domain stabilizing antiferromagnetic film 7, an Nb alloy shunt film 8, an electrode film 9, and a soft magnetic bias film 10 in that order. The laminated structure is formed by laminating a magnetoresistive film 6 and an antiferromagnetic film 7 for stabilizing a magnetic domain and processing it into a predetermined shape. Then, first, an electrode 9 is formed, and then an Nb alloy shunt film 8 and a soft magnetic film are formed. The order in which the bias films 10 are continuously laminated and processed into a predetermined shape is changed. The other structure is exactly the same as the structure of Example 14, and the manufacturing method is also completely the same. Also in this embodiment, as the shunt film and the magnetoresistive film, the Nb alloy film, NiFe alloy film, NiCo alloy film or NiF alloy film described in the first to thirteenth embodiments are used.
It goes without saying that an eCo alloy film is used. Therefore, the operation, operation, and effects of the magnetoresistive head according to the present embodiment are exactly the same as those of the magnetoresistive head 1 according to the fourteenth embodiment. In addition, when the magnetoresistive effect type magnetic head according to the present embodiment is actually used,
Alternatively, it is necessary to stack a recording magnetic head below (before stacking and forming the head) and use it in the form of a composite head.

Also, in this embodiment, the soft magnetic bias film is directly laminated on the Nb alloy shunt film. However, the effect does not change even if an insulating layer is interposed between the soft magnetic bias film and the shunt film instead of the direct lamination. Further, a hard magnetic bias film may be used instead of the soft magnetic bias film. If the bias is sufficient, it is not necessary to use a magnetic film for bias enhancement. Furthermore, a hard magnetic film may be used instead of the antiferromagnetic film for stabilizing the magnetic domain of the magnetoresistive film. However, in any of these cases, since the Nb alloy shunt film is used, a similar head output variation reduction effect of about 1/3 to 1/2 can be obtained.

Embodiment 17 The magneto-resistance effect type magnetic head according to the present embodiment is similar to that of Embodiment 1.
4 or the magneto-resistance effect type magnetic head 1 shown in FIG. 15 or the fifteenth embodiment, a magneto-resistance effect film 6, an antiferromagnetic film 7 for stabilizing a magnetic domain, an Nb alloy shunt film 8, an electrode film 9, and a soft magnetic bias film. 10, a magnetic domain stabilizing antiferromagnetic film 7 is first laminated, processed into a predetermined shape, and then a magnetoresistive effect film 6, an Nb alloy shunt film 8, a soft magnetic bias film is formed. 10 are sequentially laminated, processed into a predetermined shape, and finally the electrode 9 is formed. The other structure is exactly the same as the structure of Example 14, and the manufacturing method is also completely the same.

However, in this embodiment, the antiferromagnetic film 7
Before laminating Ni, Ni for controlling the crystal structure of the antiferromagnetic film
It is necessary to stack an Fe alloy film of several tens of degrees or more, then continuously stack an antiferromagnetic film, and further, continuously stack an NiFe alloy film of several tens of degrees or more to prevent oxidation of the antiferromagnetic film. Also, in this embodiment, the Nb alloy film and the NiFe alloy film, the NiCo alloy film, or the NiFeCo alloy film described in the first to thirteenth embodiments are used for the shunt film and the magnetoresistance effect film. Not even. Therefore, the operation, operation, and effects of the magnetoresistive head according to this embodiment having such a structure are exactly the same as those of the magnetoresistive heads 1 of Embodiments 14 and 15. When the magnetoresistive effect type magnetic head according to this embodiment is actually used, a recording magnetic head is stacked above or below (before stacking and forming the head) a composite head. Must be used in the form of

Also, in this embodiment, the soft magnetic bias film is directly laminated on the Nb alloy shunt film. However, the effect does not change even if an insulating layer is interposed between the soft magnetic bias film and the shunt film instead of directly laminating the soft magnetic bias film. Further, a hard magnetic bias film may be used instead of the soft magnetic bias film. If the bias is sufficient, it is not necessary to use a magnetic film for bias enhancement. Furthermore, a hard magnetic film may be used instead of the antiferromagnetic film for stabilizing the magnetic domain of the magnetoresistive film. However, in any of these cases, since the Nb alloy shunt film is used, a similar head output variation reduction effect of about 1/3 to 1/2 can be obtained.

Embodiment 18 The magnetoresistive head according to this embodiment is the same as the magnetoresistive head 1 of Embodiment 14 shown in FIG. 7 except that the magnetoresistive film 6 and the antiferromagnetic film 7 for stabilizing the magnetic domains are used. , The Nb alloy shunt film 8 and the electrode film 9 are laminated in this order. First, the Nb alloy shunt film 8 is laminated, then the magnetoresistive effect film 6, the magnetic domain stabilizing antiferromagnetic film 7 and The electrode film 9 is changed in the order, and the other structure is the same as the structure of the fourteenth embodiment, and the manufacturing method is also the same. Also in this embodiment, it goes without saying that the Nb alloy film, NiFe alloy film, NiCo alloy film, or NiFeCo alloy film described in Embodiments 1 to 13 are used as the shunt film and the magnetoresistive film. Absent. Therefore, the operation, operation, and effects of the magnetoresistive head according to the present embodiment are exactly the same as those of the magnetoresistive head 1 according to the fourteenth embodiment. In addition, when the magnetoresistive effect type magnetic head according to the present embodiment is actually used,
A magnetic head for recording needs to be laminated above or below (before laminating and forming the head) and used in the form of a composite head.

Embodiment 19 FIG. 10 is a sectional view of a magneto-resistance effect type magnetic head according to another embodiment of the present invention as viewed from the side facing the medium, and shows a magneto-resistance effect type magnetic head according to this embodiment. 1, the shunt film 8 and the magnetoresistive film 6
The Nb alloy film, NiFe alloy film, NiCo alloy film, or Ni described in the first to thirteenth embodiments.
An FeCo alloy film is used. In addition, the magnetoresistive effect type magnetic head 1 according to the present embodiment corresponds to the first embodiment shown in FIG.
4, the magnetoresistive film 6 of the magnetoresistive head 1
The laminated structure of the magnetic domain stabilizing antiferromagnetic film 7, the Nb alloy shunt film 8, the electrode film 9, and the soft magnetic bias film 10 is almost reversed, and the soft magnetic bias film 10, the Nb alloy shunt film 8, Antiferromagnetic film 7 and magnetoresistance effect film 6
Are laminated and processed into a predetermined shape, and finally, an electrode film is laminated to form an electrode 9. The other structure is the same as that of the magnetoresistive effect type magnetic head of the fourteenth embodiment. Therefore, although the details of the method of manufacturing the magnetic head 1 are omitted, in the case where the antiferromagnetic film 7 is stacked on the Nb alloy shunt film 8 in the magnetic head 1, the crystal structure of the antiferromagnetic film is controlled. Several hundreds of NiFe alloy film 14
It is necessary to preliminarily stack the layers on the Nb alloy shunt film 8. However, this is not particularly necessary when a hard magnetic film is used for stabilizing magnetic domains instead of the antiferromagnetic film. The magnetoresistive head 1 according to the present embodiment has the same operations, functions and effects as the magnetoresistive head 1 according to the fourteenth embodiment. When the magnetoresistive effect type magnetic head 1 according to the present embodiment is actually used, it is necessary to stack a recording magnetic head above or below this and use it in the form of a composite head.

On the other hand, in this embodiment, the soft magnetic bias film 10 is directly
Although formed under the alloy shunt film 8, the effect does not change even if an insulating layer is interposed between the shunt film and the shunt film in place of the direct shunt film, and a hard magnetic bias film is used instead of the soft magnetic bias film. May be used. If the bias is sufficient, it is not necessary to use a magnetic film for bias enhancement. However, in any of these cases, since the Nb alloy shunt film is used, a similar head output variation reduction effect of about 1/3 to 1/2 can be obtained.

Embodiment 20 The magnetoresistive head according to the present embodiment is the same as the magnetoresistive head 1 of Embodiment 19 shown in FIG. 10 except that the Nb alloy shunt film 8 and the antiferromagnetic film 7 for stabilizing the magnetic domain are used. ,
The structure in which the magnetoresistive film 6 and the electrode 9 are laminated in this order is obtained by laminating the Nb alloy shunt film 8 first, the magnetoresistive film 6, and then the magnetic domain stabilizing antiferromagnetic film 7.
Are formed into a predetermined shape by successively laminating the Nb alloy shunt film 8 and the antiferromagnetic film 7 to control the crystal structure of the antiferromagnetic film between the Nb alloy shunt film 8 and the antiferromagnetic film 7. There is no need to stack a NiFe alloy film 14 for use. However, the other structure is the same as that of Example 19, and the manufacturing method is also the same. Also, in this embodiment, the Nb alloy film, NiFe alloy film, NiCo alloy film, or NiFeCo alloy film described in Embodiments 1 to 13 are used as the shunt film and the magnetoresistance effect film. Until now, therefore, the operation, operation,
The effect is exactly the same as that of the magnetoresistive effect type magnetic head 1 of the nineteenth embodiment. When the magneto-resistance effect type magnetic head according to the present embodiment is actually used, it is necessary to stack a recording magnetic head above or below this and use it in the form of a composite head.

Example 21 The magnetoresistive heads shown in Examples 14 to 20 were first fabricated on a ceramic insulating substrate, and an alumina thin film was laminated thereon as an insulating film by about 3 μm. Laminate magnetic poles, coils, electrodes, etc. necessary for formation,
FIG. 8 shows a recording / reproducing separation type composite head, which is schematically shown in FIG.
As a result of evaluating the reproduction characteristics using a TaCr magnetic disk,
3.5 was obtained with N, and the output variation was 1/3 to 1/5 of that of the head using Nb and Ti as the conventional shunt film.
Was reduced to

Example 22 Recording in which a lower magnetic pole of an inductive recording head was formed on a ceramic insulating substrate, alumina was laminated on an insulating film to form the magnetoresistive element, and an upper magnetic pole was formed via the alumina of the insulating film. As a result of evaluating the reproduction characteristics using a read-separation type composite head and a CoTaCr magnetic disk as the medium, 3.5 was obtained in S / N, and the output variation was also compared with the head using Nb and Ti as conventional shunt films. It was reduced from 1/3 to 1/5.

Example 23 A magnetoresistive element was formed on a magnetic ferrite substrate via an insulating film, and a reproducing head using a soft magnetic film such as a magnetic ferrite or permalloy as a shield via alumina as an insulating film and two reproducing heads were used. When a recording / reproducing separation type composite head in which a recording head with a coil wound between ferrites is mechanically integrated is mounted on a magnetic tape device and driven by a constant voltage power supply, the output at 38 kfci is 3-4 mV. Output of head using Ti or Nb for shunt film
The variation was significantly reduced as compared to −3 mV.

Example 24 A read / write separation type composite head using the magnetoresistive head described in Examples 14 to 20 using the Nb alloy film of the present invention, for example, an Nb-15% Ti alloy film, was used. When mounted on a disk device and comparing the signal reproduction error rate of this magnetic disk device with that of a conventional device, the error rate was improved by about two digits.

Example 25 The S / N ratio of a reproduction signal using the same magnetic medium of CoTaCr system using a read / write separation type composite head using an Nb alloy film of the present invention, for example, an Nb-15% Ti alloy film. As a result, an improvement of about 0.3-0.7 in S / N was observed.

In the present invention, as described in the above-described embodiment, the Nb film is formed by adding the second element to the Nb film as the shunt film. The variation in the bias magnetic field strength of the head due to the variation in the electric resistance of the shunt film is compared with the vertical asymmetry of the output waveform of the head.
There is an effect of reducing the value from 3 to 1/2 or less. Therefore, there is also an effect that it is possible to greatly improve the head characteristics, particularly the S / N ratio, and to greatly reduce the variation due to the vertical asymmetry of the head output waveform.

On the other hand, if the read / write separation type composite head using the magnetoresistive effect type magnetic head of the present invention is used in an actual magnetic recording apparatus, the head characteristics such as the S / N ratio are greatly improved and the head characteristics are improved. Since the variation can be greatly reduced, it is not necessary to provide a power supply for energizing the elements with a circuit function for reducing the variation, and the load on the power supply is greatly reduced. At the same time, the reproduction error rate of the signal in recording and reproduction is reduced, so that the load on the error correction circuit is greatly reduced. Therefore, according to the present invention, a magnetic storage device having a very low error rate can be realized.

Embodiment 26 As a method of applying a bias magnetic field of a magnetoresistive head, USP. No. 4,663,685, JP-A-3-116
There is a device using a soft magnetic film, as shown in FIG. The basic configuration of a magnetoresistive head using this soft magnetic film has a three-layer structure of a soft magnetic film / spacer metal film / magnetoresistive film.

By using the Nb alloy described above as the spacer metal film, a highly efficient reproducing head can be obtained. That is, by adding a second element to Nb to increase the resistance, it is possible to prevent the shunt current from flowing to the soft magnetic film without forming a thick spacer metal film, and to provide a spacer having no variation in electric resistance. A metal film can be formed. As a result, it is possible to prevent variations in the output of the magnetoresistive head.

FIG. 11 shows this embodiment. Ni-19at.% Fe as a magnetic shield film 102 on a non-magnetic insulating substrate 101
After depositing the film by a 1 μm sputtering method and finely processing the film into a predetermined shape, the Al ₂ O ₃ film 103 serving as an insulating film is
(Ni-19at.% Fe) -6at. As a soft magnetic film.
% Ru film 104 is deposited thereon, followed by deposition of a high specific resistance metal Nb-10at.% Ta alloy film 105 to a thickness of 10 nm, and subsequently, Ni-19at.
After depositing the film with a thickness of 50 nm, it was processed into a predetermined shape to form an electrode 107. After that, the insulating film Al ₂ O ₃ film 108
Is deposited on the magnetic shield layer 109.
Ni-19at.% Fe film was deposited by a 1 μm sputtering method.

In order to form a composite head capable of recording and reproduction, an additional ₂ μm of Al ₂ O ₃ is further deposited on the composite head.
An inductive thin film head for recording is formed.

In the case of this embodiment, the thickness of the Nb alloy film is 20
Angstroms or more is enough. However, if it is too thin, it is difficult to form it. Generally, it is 100 to 200 angstroms. On the other hand, if it is too thick, it takes a long time to form, which is not preferable. Also in this embodiment, by adding the second element to Nb, variation in resistance value is small.
A high-resistance film could be obtained, and as a result, output variations of each head could be eliminated.

In this embodiment, various kinds of elements used in the above-described embodiments can be used as the types of additive elements. When used as a spacer metal film, the addition amount of the second element is determined from the viewpoint of corrosion resistance and reaction resistance. For Ti, 30 at. % Or less, Zr is 1 from the viewpoint of corrosion resistance.
2at. % Or less, V is 22 at.
% Or less, and Hf is 27 at. %, W is 6 at.% From the viewpoint of corrosion resistance. % Or less, and 27 at. % Or less, and 37 at. % Or less and 27 at. % Or less, 17 at. % Or less, Pt is 12a from the viewpoint of reaction resistance.
t. % Or less, Ni is not particularly limited from the viewpoint of reaction resistance and corrosion resistance, and Cr is 6 at. %
Hereinafter, in Mo, 9 at. % Or less.

To obtain a remarkable increase in specific resistance, FIG.
0.5 to 1 at. % Or more is desirable.

[0148]

According to the present invention, an Nb-based alloy suitable for a magnetoresistive head can be provided. By applying the alloy to a soft bias head or a shunt bias head, a magnetic head having small characteristic variations can be provided. Can be provided.

[Brief description of the drawings]

FIG. 1 is a graph illustrating the relationship between a general alloy addition amount and a change in resistance of an alloy.

FIG. 2 is a graph illustrating a reaction temperature between a magnetoresistive film and an Nb alloy film.

FIG. 3 is a graph showing a relationship between a variation in electric resistance of an Nb film and an Nb alloy film and a film thickness.

FIG. 4 is a graph showing the dependency of electric resistance change on the amount of Ti added in an NbTi alloy.

FIG. 5 is a graph showing the dependency of the reaction temperature between the NbTi alloy and the magnetoresistive film on the amount of Ti added.

FIG. 6 is a graph showing the relationship between the specific resistance of various Nb alloys and the amounts of added elements.

FIG. 7 is a cross-sectional view of the magnetoresistive head according to an embodiment of the present invention on the side facing the medium.

FIG. 8 is a sectional view of a read / write separated type composite head manufactured using the magnetoresistive effect type magnetic head shown in FIG. 7;

FIG. 9 is a sectional view of a modification of the magnetoresistive head shown in FIG. 7;

FIG. 10 is a cross-sectional view of a magnetoresistive head according to another embodiment of the present invention on the side facing the medium.

FIG. 11 is a cross-sectional view of a magnetoresistive head according to another embodiment of the present invention on the side facing the medium.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 1 ... Magnetoresistance effect type magnetic head 6 ... Magnetoresistance effect film 7 ... Antiferromagnetic film for magnetic domain stabilization 8 ... Nb alloy shunt film 9 ... Electrode film 10 ... Soft magnetic bias film

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoki Koyama 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Inside the Hitachi, Ltd. Central Research Laboratory (72) Inventor Toshio Kobayashi 1-280 Higashi Koikekubo, Kokubunji-shi, Tokyo Hitachi, Ltd. (56) References JP-A-1-217719 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 5/39 H01F 10/14

Claims (2)

(57) [Claims] A lower magnetic shield layer, a lower gap layer formed on the lower magnetic shield, a magnetoresistive film formed on the lower gap layer, and a magnetoresistive film formed on the magnetoresistive film. An echo magnetic film, a shunt film formed on the antiferromagnetic film, an electrode film formed on the shunt film, a soft magnetic bias film formed on the electrode film, and the soft magnetic bias film An upper gap layer formed on the upper gap; and an upper magnetic shield layer formed on the upper gap. The shunt film contains Nb as a main component, and includes Ti, Cr, Mo, Zr, W, Pt, and Re. , V, H
A magnetic head comprising an alloy containing any one element selected from the group consisting of f, Ta, Rh, Ni, and Ru. 2. A lower magnetic shield layer, a lower gap layer formed on the lower magnetic shield, a soft magnetic bias film formed on the lower gap layer, and a soft magnetic bias film formed on the front soft magnetic bias film. A shunt film, an antiferromagnetic film formed on the shunt film, a magnetoresistive film formed on the ferromagnetic film, an electrode film formed on the magnetoresistive film, and the electrode film An upper gap layer formed on the upper gap; and an upper magnetic shield layer formed on the upper gap.
i, Cr, Mo, Zr, W, Pt, Re, V, Hf, T
A magnetic head comprising an alloy containing any one element selected from the group consisting of a, Rh, Ni, and Ru.