JPH07312449A - Magneto resistance effect element - Google Patents

Abstract

PURPOSE:To obtain a magnetic resistance effective element comprising a laminated layer structure with a high rate of change of magnetoresistance and a small operational magnetic field intensity. CONSTITUTION:Within the title magnetoresistance effective element provided with a substrate 1 and a plurality of fine wire parts 2 arranged on the substrate 1 to be substantially in parallel with one another in the substrate 1 comprising ferromagnetic layers 2a and non-magnetic conductive layers 2b mutually laminated so as to form the antiferromagnetic couplings through the intermediary of the non-magnetic conductive layers 2b between the ferromagnetic layers 2a and the non-magnetic conductive layers 2b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive effect element (MR element) used for a magnetoresistive effect type head (MR head) and a magnetoresistive effect type sensor (MR sensor).

[0002]

2. Description of the Related Art An MR element detects a change in electric resistance of a magnetic film due to application of a magnetic field and measures the magnetic field strength or the change, and it is required that the ratio of magnetoresistive change rate / operating magnetic field strength is large. To be done.

Conventionally, in the MR head disclosed in Japanese Patent Publication No. 58-36406, a NiFe alloy (permalloy) is used as a magnetoresistive magnetic material. However, permalloy has a magnetoresistance ratio (MR
The ratio) is as small as 2 to 3%, which is not preferable as a material for MR elements.

Recently, the following magnetoresistive effect films have been known as having a large magnetoresistive change rate as compared with a bulk material such as permalloy. (1) An artificial lattice type magnetoresistive effect film in which a ferromagnetic film made of Co and a non-magnetic conductive film made of Cu are alternately laminated.

(2) Antiferromagnetic film made of MnFe alloy,
A spin-valve magnetoresistive effect film in which a ferromagnetic film made of a Co alloy, a non-magnetic conductive film made of Cu, and a ferromagnetic film made of NiFe are stacked in this order.

(3) A coercive force difference type magnetoresistive film in which a ferromagnetic film made of Fe, a non-magnetic conductive film made of Cu, and a ferromagnetic film made of Co are laminated in this order.

[0007]

The above-mentioned magnetoresistive film exhibits a relatively large magnetoresistive change rate.
In order to improve the performance of the MR element, it is required to further reduce the operating magnetic field strength.

It is an object of the present invention to provide a magnetoresistive effect element having a magnetoresistive effect film having a laminated structure having a large magnetoresistive change rate and a small operating magnetic field strength.

[0009]

The magnetoresistive effect element of the present invention comprises a substrate and a plurality of fine line portions provided on the substrate so as to be substantially parallel to each other.

In the present invention, the aspect ratio of the fine line portion is preferably larger than 1, and the aspect ratio indicates the length of the fine line portion / the width of the fine line portion. In order to make the aspect ratio larger than 1, the shape of the fine line portion is set so that the length of the fine line portion is longer than the width of the fine line portion. Further, the thickness of the thin wire portion is considerably smaller than the width of the thin wire portion, and thus the width and the thickness of the thin wire portion are smaller than the length of the thin wire portion. In the present invention, the aspect ratio of the thin line portion is more preferably 10 or more.

In the present invention, the width of the fine line portions and the distance between the fine line portions are each preferably 10 μm or less,
More preferably, it is within the range of 0.1 to 2 μm. According to the first aspect of the present invention, the thin line portion has a structure in which ferromagnetic layers and non-magnetic conductive layers are alternately laminated, and the thin wire portions are arranged between the ferromagnetic layers laminated via the non-magnetic conductive layers. Ferromagnetic coupling is formed. This is a laminated structure of the above-mentioned artificial lattice type magnetoresistive effect film. Therefore, for example, a Co layer is used as the ferromagnetic layer and a Cu layer is used as the non-magnetic conductive layer.

According to the second aspect of the present invention, the thin wire portion is
The first ferromagnetic layer, the non-magnetic conductive layer provided on the first ferromagnetic layer, and the magnetic moment of the first ferromagnetic layer provided on the non-magnetic conductive layer in a state where the external magnetic field is weak. A second magnetic moment that tends to be oriented in an antiparallel state with
And a ferromagnetic layer of.

In a first embodiment of the second aspect,
The laminated structure of the thin line portion further includes an antiferromagnetic layer provided on the first ferromagnetic layer or the second ferromagnetic layer.
Therefore, in the first embodiment of this second aspect,
It has a structure in which an antiferromagnetic layer, a first ferromagnetic layer, a nonmagnetic conductive layer, and a second ferromagnetic layer are stacked. Therefore,
The thin line portion in the first embodiment has a structure of a spin valve type magnetoresistive effect film. In this first embodiment, for example, a MnFe layer is used as the antiferromagnetic layer, a Co layer is used as the first ferromagnetic layer, a Cu layer is used as the nonmagnetic conductive layer, and a NiFe layer is used as the second ferromagnetic layer. .

In the second embodiment according to the second aspect of the present invention, a ferromagnetic layer having a coercive force different from that of the second ferromagnetic layer is used as the first ferromagnetic layer. Therefore, the thin line portion in the second embodiment has the structure of the coercive force difference type magnetoresistive effect film. This embodiment has a structure in which a first ferromagnetic layer, a non-magnetic conductive layer, and a second ferromagnetic layer are stacked in this order. In the second embodiment, for example, a Fe layer is used as the first ferromagnetic layer, a Cu layer is used as the non-magnetic conductive layer, and a Co layer is used as the second ferromagnetic layer.

[0015]

The magnetoresistive effect element according to the present invention comprises:
A large magnetoresistive effect is exhibited for the following reasons.

The conduction electrons passing through the nonmagnetic conductive layer are
The scattering probability changes depending on the direction of the magnetic moment of the ferromagnetic layer laminated via the non-magnetic conductive layer. The scattering probability is the smallest when the directions of the magnetic moments are parallel to each other, and the maximum is the scattering probability when the directions of the magnetic moments are antiparallel to each other.

Since there are domains in the ferromagnetic layer,
The magnetic moment has a degree of freedom in the in-plane direction, and the above-mentioned parallel and antiparallel states are incomplete. In the present invention, the magnetoresistive effect film has a thin line portion. Therefore, due to this shape anisotropy, the degree of freedom of the magnetic moment of the ferromagnetic layer is reduced, and the ferromagnetic layer is oriented more parallel to the extending direction of the thin line portion. As a result, the parallel and antiparallel states described above are more complete.

Further, according to the present invention, since the thin wire portions are provided so as to be substantially parallel to each other, due to the interaction such as the dipole interaction of the magnetic moment, the corresponding strong wire portions of the adjacent thin wire portions. It is believed that the magnetic moments of the magnetic layers tend to align more parallel. As a result, under a weak external magnetic field, the magnetic moments of the ferromagnetic layers stacked via the non-magnetic conductive layer are substantially antiparallel. This also makes the above-mentioned parallel and anti-parallel states more complete.

Therefore, in the presence of an appropriate weak external magnetic field, the conduction electrons in the non-magnetic conductive layer pass in a direction substantially parallel to the direction in which the thin wire portion extends, and the conduction electrons pass in one direction and the ferromagnetism in one direction. The magnetic moments of the layers are almost in the opposite directions. As a result, the conduction electrons are largely scattered and the resistance increases.

When a strong external magnetic field, that is, an external magnetic field having a strength equal to or higher than the saturation magnetic field is present along the direction in which the thin line portion extends, the direction of the magnetic moment of the ferromagnetic layer laminated via the nonmagnetic conductive layer. Are approximately parallel to the direction of the external magnetic field. Further, the conduction electrons in the non-magnetic conductive layer pass in a direction substantially parallel to the extending direction of the thin wire portion and in a direction substantially parallel to the direction of the external magnetic field. Therefore, the passing direction of conduction electrons in the nonmagnetic conductive layer and the direction of the magnetic moment of the ferromagnetic layer are substantially parallel. Therefore, the scattering becomes small and the resistance becomes small.

As described above, in the magnetoresistive effect element according to the present invention, since the structure of the plurality of thin wire portions is provided, the degree of freedom of the magnetic moment is reduced and the magnetoresistive effect is increased.

In the magnetoresistive effect element of the present invention, the first reason that the operating magnetic field becomes small is the effect of shape anisotropy. That is, since the magnetic moment does not have a degree of freedom in the width direction of the thin wire, it is not digitally rotated but is digitally inverted. Secondly, it is considered that the operating magnetic field becomes small because a plurality of magnetic moments operate coherently (in phase).

In the first aspect of the present invention, the structure of the artificial lattice type magnetoresistive film is formed in the thin line portion. In such a magnetoresistive film structure, when the external magnetic field is weak, the magnetic moments of the ferromagnetic layers adjacent to each other via the nonmagnetic conductive layer tend to become antiparallel. As a result, a large magnetoresistive effect is exhibited as described above.

In a second aspect according to the present invention, there is provided a thin wire portion in which a first ferromagnetic layer, a non-magnetic conductive layer and a second ferromagnetic layer are laminated. The second ferromagnetic layer has a magnetic moment that tends to be oriented antiparallel to the magnetic moment of the first ferromagnetic layer when the external magnetic field is weak. Therefore, the magnetic moment of the first ferromagnetic layer,
The magnetic moment of the second ferromagnetic layer tends to be in an antiparallel state. As a result, the large magnetoresistive effect as described above can be obtained.

In a first embodiment according to the second aspect, an antiferromagnetic layer, a first ferromagnetic layer, a nonmagnetic conductive layer, and a second
Has a structure of a spin-valve type magnetoresistive film in which ferromagnetic layers are laminated. When the external magnetic field is weak, the magnetic moment of the first ferromagnetic layer adjacent to the antiferromagnetic layer tends to be parallel to the magnetic moment of the antiferromagnetic layer.
The magnetic moments of the first and second ferromagnetic layers tend to be antiparallel to each other.

In a second embodiment according to the second aspect, a structure of a coercive force difference type magnetoresistive effect film in which a first ferromagnetic layer, a non-magnetic conductive layer and a second ferromagnetic layer are laminated is provided. Have When the external magnetic field is weak, the magnetic moments of the first and second ferromagnetic layers tend to be antiparallel to each other due to this coercive force difference.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view showing a magnetoresistive effect element of an embodiment according to the first aspect of the present invention. With reference to FIG. 1, a plurality of thin line portions 2 are provided on a non-magnetic substrate 1 made of glass so as to be substantially parallel to each other.
The distance T between the thin wire portions 2 is about 2 μm. Also the thin line part 2
Has a width W of about 2 μm. The length of the thin wire portion 2 is about 90 μm
Is. Therefore, the aspect ratio of the thin line portion 2 of this embodiment is about 45.

The thin line portion 2 is a laminated body formed by alternately stacking 29 sets of a ferromagnetic layer 2a made of Co having a film thickness of 15Å and a non-magnetic conductive layer (nonmagnetic metal layer) 2b made of Cu having a film thickness of 20Å. (Layered structure) 3.

2 (a) to 2 (d) are sectional views showing the manufacturing steps of the magnetoresistive effect element of the embodiment shown in FIG.
With reference to FIG. 2A, first, the glass non-magnetic substrate 1
A resist is applied on the entire surface of the substrate by a spin coating method or the like and then heat-treated to form a resist film 4 having a thickness of 1 to 2 μm.

With reference to FIG. 2B, next, the resist film 4 is exposed in a fine line shape. The thin line-shaped exposed portions are formed with a predetermined width so as to be parallel to each other with a constant interval. After the exposure, the resist film 4 is developed to remove the exposed portion, and a thin linear resist film 5 is formed.

With reference to FIG. 2C, next, a ferromagnetic layer and a non-magnetic conductive layer are alternately formed on the substrate 1 and the resist film 5 by an electron beam evaporation method to form a laminate 3. To do.
Next, referring to FIG. 2D, the resist film 5 is removed,
By the so-called lift-off method, the distance T is
A stacked body 3 having a width W and formed in parallel with each other is formed. This laminated body 3 becomes the thin line portion 2.

A magnetoresistive effect element (embodiment 1) of the embodiment shown in FIG. 1 and a magnetoresistive effect element in which the same magnetoresistive effect film as that of the embodiment 1 is formed on a substrate except that the thin wire structure is not used (comparative example). For 1), the external magnetic field is -500 to +500.
The magnetic resistance when changed in the range of Oe was measured by the four-terminal method, and the measurement result showed that the magnetic resistance change rate (MR ratio = Δ
R / R) was determined.

The MR ratio is (R (H) -R _min ) / R _min
It is defined by × 100 (%). Where R (H) and R
_min indicates the resistance value and the minimum resistance value at the applied magnetic field strength H, respectively.

FIG. 3 is a graph showing the relationship between the MR ratio and the applied magnetic field strength of the magnetoresistive effect elements of Example 1 and Comparative Example 1. Table 1 shows the values of the maximum MR ratio and the operating magnetic field of Example 1 and Comparative Example 1.

[0035]

[Table 1]

As is clear from FIG. 3 and Table 1, the maximum MR ratio of the magnetoresistive effect element of Example 1 is about 34%, which is much larger than about 17% of Comparative Example 1. Also, the operating magnetic field is about 310 Oe in Comparative Example 1, whereas it is about 150 Oe in Example 1, which is remarkably small. Therefore, it can be seen that the saturation magnetic field of Example 1 is smaller than that of Comparative Example 1.

FIG. 4 is a schematic diagram for explaining the reason why the MR ratio of the magnetoresistive effect element according to the present invention becomes large. FIG. 4A shows a magnetoresistive effect element of an example according to the present invention, and FIG. 4B shows a conventional magnetoresistive effect element. 4 (a) and 4 (b) both show a state in which a weak external magnetic field exists.

With reference to FIG. 4A, in the magnetoresistive effect element of this embodiment, the nonmagnetic conductive layer 33 is interposed,
The ferromagnetic layer 32 and the ferromagnetic layer 34 are laminated. The ferromagnetic layer 32, the non-magnetic conductive layer 33, and the ferromagnetic layer 34 are
All are formed in a thin line shape.

Referring to FIG. 4B, the nonmagnetic conductive layer 4
The ferromagnetic layer 42 and the ferromagnetic layer 44 are stacked with the layer 3 interposed therebetween. The ferromagnetic layer 42, the non-magnetic conductive layer 43, and the ferromagnetic layer 44 are in the form of conventional magnetoresistive films, and are film-shaped.

Referring to FIG. 4A, the non-magnetic conductive layer 3
Since the antiferromagnetic coupling exists between the ferromagnetic layers 32 and 34 laminated via 3, the magnetic moment 31 of the ferromagnetic layer 32 and the magnetic moment 35 of the ferromagnetic layer 34 may be antiparallel. To do.

In the magnetoresistive effect element of this embodiment,
The ferromagnetic layers 32 and 34 are each formed in a thin line shape. Therefore, due to the shape anisotropy effect, the magnetic moments 31 and 35 of the ferromagnetic layers 32 and 34 tend to be more antiparallel to each other. Further, since the plurality of thin line portions are provided substantially parallel to each other, the magnetic moments of the corresponding ferromagnetic layers may become parallel due to the interaction between the magnetic moments of the corresponding ferromagnetic layers of the adjacent thin line portions. To do. As a result, the magnetic moments of the ferromagnetic layers 32 and 34 stacked with the non-magnetic conductive layer 33 approach a more perfect antiparallel state.

Also in the conventional magnetoresistive element shown in FIG. 4B, since the antiferromagnetic coupling exists between the ferromagnetic layers 42 and 44 laminated with the non-magnetic conductive layer 43 interposed therebetween, strong coupling is achieved. Magnetic moment 4 of magnetic layer 42 and ferromagnetic layer 44
1 and 45 tend to be oriented antiparallel to each other. However, since the ferromagnetic layer 42 and the ferromagnetic layer 44 are formed in a film shape, their magnetic moments 41 and 45 are formed.
Has a large degree of freedom in the in-plane direction. Therefore, FIG.
As shown in (b), the magnetic moment 4 of the ferromagnetic layer 42
1 and the magnetic moment 45 of the ferromagnetic layer 44 are not in the antiparallel state.

As described above, in the magnetoresistive effect element according to the present invention, when an appropriate weak external magnetic field exists, the conduction direction of conduction electrons passing through the nonmagnetic conductive layer and the nonmagnetic conductivity. Since the angle formed by one of the magnetic moments of the ferromagnetic layers laminated via the layers approaches 180 degrees compared with the case of the element having the conventional film-like magnetoresistive film, the scattering of conduction electrons Becomes larger, and the resistance becomes larger than that of the conventional magnetoresistive effect element.

When an external magnetic field having a magnitude greater than the saturation magnetic field is applied, the magnetic moments of the ferromagnetic layers laminated via the nonmagnetic conductive layer become parallel to each other, and the passing direction of conduction electrons and the magnetic moment The directions are parallel. Therefore, the scattering of electrons is small. This is as small as the magnetoresistive effect element according to the present invention shown in FIG. 4A and the conventional magnetoresistive effect element shown in FIG. 4B. Therefore,
Both R _min are of similar magnitude.

As described above, the magnetoresistive effect element according to the present invention has a larger maximum resistance value than that of the conventional one and has the same R _{min as} that of the conventional one, so that the maximum MR ratio becomes large. In the magnetoresistive effect element according to the present invention, the first reason that the operating magnetic field becomes small is the effect of shape anisotropy. That is, since the magnetic moment does not have a degree of freedom in the width direction of the thin wire, it is not digitally rotated but is digitally inverted. Secondly, it is considered that a plurality of magnetic moments operate coherently (in phase).

For comparison, a fine wire structure made of a NiFe alloy was formed on a glass substrate, and the maximum MR ratio and operating magnetic field were measured. The magnetoresistive effect element of this comparison has a thin wire structure as shown in FIG. 1, but the thin wire portion does not have a laminated film structure as shown in FIG. 1, but has a single composition of NiFe alloy. . In the comparative magnetoresistive effect element having the thin wire portion made of the NiFe alloy, the maximum MR ratio and the numerical value of the operating magnetic field were not good values as in the present invention. Also, the smaller the width of the thin line portion, the worse the value. The reason why the effect of the present invention cannot be obtained in the magnetoresistive effect element having the thin wire portion made of the NiFe alloy is that the conduction electrons pass through the magnetic body in the NiFe alloy and the non-magnetic conductive element as in the present invention is obtained. It is thought that this is because it does not pass through the sex layer. That is, it is considered that this is based on the difference in the principle of obtaining the magnetoresistive effect.

In the magnetoresistive effect element according to the first aspect of the present invention, the combination of the ferromagnetic layer and the non-magnetic conductive layer may be other than those in the above embodiments. For example, the ferromagnetic layer may be selected from Fe layer, Co layer, alloys thereof, and the like. The non-magnetic conductive layer may be selected from Cu layer, Ag layer and the like. In order to generate antiferromagnetic coupling between the ferromagnetic layers laminated via the nonmagnetic conductive layer,
It is necessary to appropriately select the thickness of the nonmagnetic conductive layer.

FIG. 5 is a sectional view showing the magnetoresistive effect element according to the first embodiment of the second aspect of the present invention. Figure 5
With reference to FIG.
A thin line portion 12 having a width W is provided so as to be separated from each other. In this embodiment, the distance T is about 2 μm and the width W is about 2 μm. The length of the thin line portion 12 is 90 μm. Therefore, the aspect ratio is 45. The thin line portion 12 is the antiferromagnetic layer 12
a, a first ferromagnetic layer 12b, a non-magnetic conductive layer 12c, and a second ferromagnetic layer 12d are laminated.

The antiferromagnetic layer 12a is made of MnF having a film thickness of 80Å.
It is formed from an e-alloy (Mn 50% by weight, Fe 50% by weight) film. The first ferromagnetic layer 12b is made of C having a film thickness of 50Å.
It is formed from an o film. The nonmagnetic conductive layer 12c is formed of a Cu film having a film thickness of 22Å. The second ferromagnetic layer 12d is formed of a NiFe alloy (Ni 80% by weight, Fe 20% by weight) film having a film thickness of 75Å.

In the magnetoresistive effect element shown in FIG. 5, as in the embodiment shown in FIG. 1, a thin linear resist film is formed on the substrate 11, and a laminated film is formed on the resist film and the substrate by electron beam evaporation. Can be formed and then the resist film can be lifted off.

The magnetoresistive effect element of the embodiment shown in FIG. 5 (embodiment 2) and the magnetoresistive effect element (comparative example 2) having the same laminated film as that of the embodiment 2 except that the thin wire structure is not used. The magnetoresistance change rate was obtained in the same manner as in Example 1.

FIG. 6 is a graph showing the relationship between the MR ratio and the applied magnetic field strength in Example 2 and Comparative Example 2. Table 2 shows Example 2
3 shows the maximum MR ratio and operating magnetic field of Comparative Example 2.

[0053]

[Table 2]

As is clear from FIG. 6 and Table 2, the maximum M
Regarding the R ratio, the element of Example 2 has a value of about 13%, which is significantly higher than the value of the element of Comparative Example 2, which is about 5%. The operating magnetic field is also about 300 Oe in Comparative Example 2, whereas it is 240 Oe in Example 2 and is remarkably small. Therefore, it can be seen that the saturation magnetic field of Example 2 is smaller than that of Comparative Example 2.

In the spin-valve type magnetoresistive film as in this example, a high MR ratio and a low operating magnetic field can be obtained by the above-described shape anisotropy and coherent operation of a plurality of magnetic moments.

Also in the laminated film including the antiferromagnetic layer, the first ferromagnetic layer, the nonmagnetic conductive layer, and the second ferromagnetic layer,
Various materials can be selected. FIG. 7 is a cross-sectional view showing a magnetoresistive effect element of the second embodiment according to the second aspect of the present invention. Referring to FIG. 7, on glass non-magnetic substrate 21, a plurality of thin line portions 22 having a width W and having a distance T and parallel to each other are provided. The thin line portion 22 includes the first ferromagnetic layer 22a, the nonmagnetic conductive layer 22b, and the second ferromagnetic layer 22a.
Of the ferromagnetic layer 22c. The first ferromagnetic layer 22a is formed of an Fe film having a film thickness of 56Å. The non-magnetic conductive layer 22b has a film thickness of 50.
It is formed from a Cu film of Å. Second ferromagnetic layer 22c
Is formed of a Co film having a film thickness of 48 Å.

In the magnetoresistive effect element shown in FIG. 7, as in the embodiment shown in FIG. 1, a fine line resist film is formed on the substrate 21, and electron beam evaporation is performed on the fine line resist film and the substrate. After forming the above-mentioned laminated film by the method, the resist film can be lifted off.

Magnetoresistive effect element shown in FIG. 7 (Example 3)
And a magnetoresistive effect element (Comparative Example 3) using a laminated film similar to that of Example 3 except that the thin-line structure is not used.
The magnetoresistance change rate was obtained in the same manner as in Example 1 above.

FIG. 8 is a diagram showing the relationship between the MR ratio and the applied magnetic field strength in the magnetoresistive effect elements of Example 3 and Comparative Example 3. Table 3 shows the values of the maximum MR ratio and the operating magnetic field of Example 3 and Comparative Example 3.

[0060]

[Table 3]

As is clear from FIG. 8 and Table 3, the maximum M
The R ratio of Example 3 is about 9%, which is significantly higher than the R ratio of about 3% of Comparative Example 3. The operating magnetic field is also about 250 Oe in Comparative Example 3, whereas it is 170 Oe in Example 3 and is remarkably small. Therefore, it can be seen that the saturation magnetic field of Example 3 is smaller than that of Comparative Example 3.

As described above, by the coherent operation of the shape anisotropy and the plurality of magnetic moments in the third embodiment, a high MR ratio and a low operating magnetic field can be obtained as in the first embodiment.

Also in this embodiment, various materials can be selected as long as there is a difference in coercive force between the first ferromagnetic layer and the second ferromagnetic layer. For example, the first ferromagnetic layer,
A NiFe alloy layer, a Cu layer, and a Co layer may be used as the nonmagnetic conductive layer and the second ferromagnetic layer, respectively.

In each of the above embodiments, the distance T between the fine line portions and the width W of the fine line portions are set to about 2 μm, but they are not limited to these values. As described above, the distance T and the width W are preferably within the range of 0.1 to 2 μm.

Although the length of the thin line portion is 90 μm, it is not limited to this value. The length of the thin line portion is preferably at least 200 μm or less. In the present invention, it is most preferable that the thickness of each layer constituting each thin line portion and the positions of their heights are the same, but they do not necessarily have to be exactly the same, and they are almost the same. Just do it.

FIG. 9 is a plan view showing a state in which electrodes are attached to the magnetoresistive effect element shown in FIG. As shown in FIG. 9, a first conductive layer 24 and a second conductive layer 25 made of, for example, Au are provided on both ends of the substrate 21. Electrodes 27a and 27b for passing a current and electrodes 26a and 26b for reading a voltage are provided on each of the first conductive layer 24 and the second conductive layer 25. Since the first conductive layer 24 and the second conductive layer 25 are connected to the thin wire portions 22, a current is passed between the electrodes 27a and 27b, and the electrode 26a
The resistance can be measured by reading the voltage between and 26b.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a magnetoresistive effect element of an embodiment according to the first aspect of the present invention.

2 (a) to 2 (d) are cross-sectional views showing a manufacturing process of the magnetoresistive effect element of the embodiment shown in FIG.

FIG. 3 is a diagram showing the relationship between the MR ratio and the applied magnetic field strength of the magnetoresistive effect element of the embodiment shown in FIG.

4 (a) and 4 (b) are schematic diagrams showing a magnetic moment of a magnetoresistive effect element according to the present invention.

FIG. 5 is a sectional view showing a magnetoresistive effect element according to a first embodiment of a second aspect of the present invention.

FIG. 6 is a diagram showing the relationship between the MR ratio and the applied magnetic field strength of the magnetoresistive effect element of the embodiment shown in FIG.

FIG. 7 is a sectional view showing a magnetoresistive effect element according to a second embodiment of the second aspect of the present invention.

8 is a diagram showing the relationship between the MR ratio and the applied magnetic field strength of the magnetoresistive effect element of the embodiment shown in FIG.

FIG. 9 is a plan view showing a magnetoresistive effect element according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate (base) 2a ... Ferromagnetic layer 2b ... Nonmagnetic conductive layer 2 ... Thin line part 3 ... Laminated body 11 ... Substrate (base) 12 ... Fine line part 12a ... Antiferromagnetic layer 12b ... 1st ferromagnetic layer 12c ... Nonmagnetic conductive layer 12d ... Second ferromagnetic layer 13 ... Laminated body 21 ... Substrate (base) 22 ... Fine line portion 22a ... First ferromagnetic layer 22b ... Nonmagnetic conductive layer 22c ... Second strong layer Magnetic layer 23 ... Laminated body

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area H01F 10/08

Claims (13)

[Claims] 1. A substrate, and a plurality of thin line portions provided on the substrate so as to be substantially parallel to each other, wherein the thin line portions are formed by alternately stacking a ferromagnetic layer and a non-magnetic conductive layer. A magnetoresistive effect element having a structure, in which antiferromagnetic coupling is formed between the ferromagnetic layers that are stacked via the nonmagnetic conductive layer. 2. The magnetoresistive effect element according to claim 1, wherein at least 10 sets of the ferromagnetic layer and the nonmagnetic conductive layer are laminated. 3. The magnetoresistive effect element according to claim 1, wherein the ferromagnetic layer is a Co layer and the non-magnetic conductive layer is a Cu layer. 4. A substrate, and a plurality of thin line portions provided on the substrate so as to be substantially parallel to each other, wherein the thin line portions include a first ferromagnetic layer and the first ferromagnetic layer. A non-magnetic conductive layer provided on the layer, and a magnetic moment provided on the non-magnetic conductive layer and oriented to be antiparallel to the magnetic moment of the first ferromagnetic layer when the external magnetic field is weak. A magnetoresistive effect element having a structure in which a second ferromagnetic layer having a is laminated. 5. The magnetic structure according to claim 4, wherein the laminated structure of the thin line portion further includes an antiferromagnetic layer provided on at least one of the first ferromagnetic layer and the second ferromagnetic layer. Resistance effect element. 6. The antiferromagnetic layer is a MnFe layer, the first ferromagnetic layer is a Co layer, the non-magnetic conductive layer is a Cu layer, and the second ferromagnetic layer is NiFe. The magnetoresistive effect element according to claim 5, which is a layer. 7. The magnetoresistive element according to claim 4, wherein the second ferromagnetic layer is a ferromagnetic layer having a coercive force different from that of the first ferromagnetic layer. 8. The magnetoresistive device according to claim 7, wherein the first ferromagnetic layer is a Fe layer, the non-magnetic conductive layer is a Cu layer, and the second ferromagnetic layer is a Co layer. Effect element. 9. The magnetoresistive effect element according to claim 1, wherein the width of the thin wire portions and the distance between the thin wire portions are 10 μm or less. 10. The magnetoresistive effect element according to claim 1, wherein the thin wire portion has an aspect ratio of 1 or more. 11. The magnetoresistive effect element according to claim 1, wherein the thin wire portion has an aspect ratio of 10 or more. 12. A substrate, and a plurality of thin line portions provided on the substrate so as to be substantially parallel to each other, wherein the thin line portions include a first ferromagnetic layer and the first ferromagnetic layer. A non-magnetic conductive layer provided on the layer, a second ferromagnetic layer provided on the non-magnetic conductive layer, and at least one of the first ferromagnetic layer and the second ferromagnetic layer. A magnetoresistive effect element having a structure in which an antiferromagnetic layer provided on the substrate is laminated. 13. A substrate, and a plurality of thin line portions provided on the substrate so as to be substantially parallel to each other, wherein the thin line portions include a first ferromagnetic layer and the first ferromagnetic layer. Magnetoresistance having a structure in which a nonmagnetic conductive layer provided on a layer and a second ferromagnetic layer provided on the nonmagnetic conductive layer and having a coercive force different from that of the first ferromagnetic layer are laminated. Effect element.