JP2002176210A - Magneto-impedance effect element and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce resistance and power consumption in a magneto-impedance effect element and to obtain efficient change in the output voltage even if a drive voltage is low, by constructing a magneto-sensitive section in such a manner that a soft magnetic section is brought into contact with a conductive section having specific resistance lower than that of the soft magnetic section. SOLUTION: A magneto-sensitive section 25 is formed by alternately stacking soft magnetic thin films 22, 24 and a conductive thin film 23. When an alternating drive current is supplied to the section 25, the current is divided into currents flowing through the films 22, 24 and a current flowing through the film 23. As a result, the DC resistance in the section 25 is decreased when the alternating drive current flows, thereby reducing the power consumption in the element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-impedance effect element usable as a magnetic field sensor.
The present invention relates to a magneto-impedance element having a good magnetic field detection sensitivity even when a resistance value of the magneto-impedance element can be reduced, power consumption can be reduced, and a bias magnetic field can be reduced, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, with the rapid development of information devices, measuring devices, control devices, and the like, there has been a demand for a magnetic field sensor having a smaller size, higher sensitivity, and faster response (high-frequency operation) than the conventional magnetic flux detection type. And the magneto-impedance effect (Magn
An element (magneto-impedance effect element) having eto-Impedance-Effect has been attracting attention.

The basic principle of a magneto-impedance effect element is that an output voltage due to impedance generated by applying a small alternating current to a magnetic wire formed in a wire, ribbon, or thin film is changed by an externally applied magnetic field. Device.

The change in the impedance of the magnetically sensitive portion made of a soft magnetic material due to the application of an external magnetic field is caused by the "skin effect" in which an alternating current flows near the surface when an alternating current is applied to the magnetic material. It is known that the change is caused by an external magnetic field.

FIG. 29 is a perspective view of a conventional magneto-impedance effect element. The magneto-impedance effect element M shown in FIG. 29 has a magnetically sensitive part 12 formed by forming a thin film of a soft magnetic material on a substrate 11 made of a non-magnetic material such as alumina titanium carbide by a sputtering method or a vapor deposition method. And electrode portions 13 and 1 formed of a conductive material such as Cu and joined to both ends of the magnetic sensing portion 12.
3. The magnetic sensing portion 12 is formed in a substantially rectangular or linear pattern. The element length and the element width of the magnetic sensing unit 12 in FIG.

FIG. 30 is a circuit diagram showing a magnetic field detecting circuit formed using a conventional magneto-impedance effect element. In the circuit shown in FIG.
When an external magnetic field Hex is applied in the element length direction of the magnetic sensing unit 12 in a state where the alternating current Iac in the MHz band from c is applied, the output voltage Emi due to the material-specific impedance is applied to both ends of the magnetic sensing unit 12. Then, the amplitude of the output voltage Emi changes within a range of several tens of percent corresponding to the intensity of the external magnetic field Hex.

[0007]

In the conventional magnetic impedance effect element, the magnetic sensing portion 12 is formed of a single-layer soft magnetic thin film. The drive AC current flows through the magnetic sensing unit 12.

However, the soft magnetic thin film forming the magnetic sensing part 12 is often formed of a material having a high specific resistance.
DC current loss tended to increase. Further, when the soft magnetic thin film is formed of a material having a high specific resistance, the skin thickness when the driving AC current flows increases, the DC resistance value decreases, and when the external magnetic field is applied to the magnetic sensing unit 12, ,
The change in impedance is reduced. Therefore, a sufficient amount of change in the output voltage cannot be obtained particularly when the driving voltage is low. As a result, a sufficient output change amount with respect to the magnetic field cannot be obtained, and a problem has arisen that the magnetic field detection sensitivity is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and a soft magnetic material portion and a conductor portion having a lower specific resistance than the soft magnetic material portion are in contact with the magnetic sensing portion. By doing so, the resistance value of the magneto-impedance effect element can be reduced, power consumption can be reduced, and a sufficient amount of change in output voltage can be obtained even when the drive voltage is low, and its manufacture. The aim is to provide a method.

[0010]

According to the present invention, a magnetic sensing portion having a magneto-impedance effect and an electrode portion for supplying a drive alternating current to the magnetic sensing portion are provided on a substrate made of a non-magnetic material. In the magneto-impedance effect element
The magnetic sensing portion has a soft magnetic material portion formed of a soft magnetic material, and a conductor portion having a lower specific resistance than the soft magnetic material portion, and the soft magnetic material portion and the conductor portion are It is characterized by being in contact at least partially.

When the magnetic sensing portion has a structure in which the soft magnetic portion and a conductive portion having a lower specific resistance than the soft magnetic portion are in contact with each other, a driving AC current is applied to the magnetic sensing portion. When given, this drive AC current flows separately into a current flowing in the soft magnetic body portion and a current flowing in the conductor portion. As a result, the DC resistance value of the magnetic sensing unit when the driving AC current flows is reduced, and the power consumption of the magneto-impedance effect element can be reduced.

Further, in the present invention, since the magnetically sensitive portion has a structure in which the soft magnetic material portion having high magnetic permeability and the conductive material portion having high electrical conductivity are in contact with each other, The skin thickness of the driving AC current flowing through the thinner becomes thinner, the DC resistance value increases, and a large magneto-impedance effect can be generated. Even with a low driving voltage, a sufficient amount of change in the output voltage with respect to the magnetic field can be obtained. Can be.

[0013] In the magneto-impedance effect element according to the present invention, the magnetically sensitive portion may be such that the soft magnetic material portion and the conductor portion are alternately laminated.

Further, the uppermost layer and the lowermost layer of the magnetic sensing portion are the soft magnetic portions, and the soft magnetic portions of the uppermost layer and the lowermost layer are magnetically at least at the ends in the element width direction. They may be combined.

[0015] In particular, when the magnetic sensing portion is formed by alternately laminating the soft magnetic material portion and the conductor portion,
When the film thickness of the magnetically sensitive part is increased, the film stress is increased, and the magnetically sensitive part is easily peeled off from the substrate. Therefore,
When the dimension in the element width direction of the upper surface of the magneto-sensitive section is shorter than the dimension in the element width direction of the bottom face of the magneto-sensitive section, film stress can be dispersed, and the magneto-sensitive section can be prevented from peeling off from the substrate. The magneto-sensitive portion can be maintained in a stable shape. For example,
The magnetic sensing portion may be formed such that the dimension in the element width direction gradually decreases as the distance from the surface of the substrate increases.

Preferably, the soft magnetic portion and the conductor portion are electrically insulated by an insulating layer, and the driving AC current is passed only to the conductor portion.

[0017] When the soft magnetic material portion and the conductor portion are electrically insulated by an insulating layer, and the drive AC current is applied only to the conductor portion, an excitation magnetic field is efficiently generated by the drive AC current. And a more significant magneto-impedance effect can be obtained.

Further, in the present invention, when an external magnetic field is applied in the element longitudinal direction of the magneto-sensitive section to which a driving AC current is applied, the external voltage that maximizes the output voltage from both ends of the magneto-sensitive section is provided. It is preferable that the absolute value of the magnitude of the magnetic field is 400 (A / m) or less.

When the external magnetic field is applied in the element longitudinal direction of the magnetic sensing portion to which a driving AC current is applied, and the magnitude of the external magnetic field is changed, a change in an output voltage from the magnetic sensing portion is caused. The rate becomes maximum near the maximum value of the output voltage. Therefore, when the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from the magneto-sensitive section decreases, the rate of change of the output voltage when the magnitude of the external magnetic field is near 0 is reduced. growing. Therefore, the magnitude of the bias magnetic field applied to the magnetic sensing portion can be reduced.

In particular, the absolute value of the magnitude of the external magnetic field which maximizes the output voltage from both ends of the magnetic sensing portion is 400 (A).
/ M) or less, a magnetic field generated from a magnetic material made of a magnetic material formed around or superimposed on the magneto-impedance effect element,
It can be used as a bias magnetic field.

Further, even when the bias magnetic field is applied by a coil wound around the magnetic sensing part, the number of turns of the coil is reduced, and the process for manufacturing the magnetic sensing part can be simplified. become.

Further, downsizing required when applying the magneto-impedance effect element to a magnetic head or a weak magnetic field detector is facilitated.

Further, since the DC current applied to the coil for generating the bias magnetic field can be reduced, the power saving of the magneto-impedance effect element is facilitated.

The magneto-sensitive portion is usually formed in a substantially rectangular or linear shape, but may be formed in a U-shape or a broken shape. The element longitudinal direction at this time is an extension direction of the longest linear portion in the magneto-sensitive portion,
The direction coincides with the direction perpendicular to the excitation direction of the magnetic field generated by the driving AC current.

The absolute value of the magnitude of the external magnetic field which maximizes the output voltage from both ends of the magnetic sensing portion is 320 (A).
/ M) or less, and more preferably the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magneto-sensitive portion is 160 (A / m) or less. .

Further, according to the present invention, the element width W of the magneto-sensitive portion is
It is preferable that the ratio (aspect ratio) W / L of the element length L is 0.1 or less.

The inventor of the present invention reduces the ratio (aspect ratio) W / L of the element width W to the element length L of the magneto-sensitive effect element when forming the magneto-sensitive part of the magneto-impedance effect element. It has been found that the magnetic field detection sensitivity of the magneto-impedance effect element improves as the value increases. In particular, it has been found that when the aspect ratio is 0.1 or less, the magnetic field detection sensitivity of the magneto-impedance effect element is significantly improved.

Since the magnetic sensing portion is excited by a high frequency alternating current, a strong skin effect appears. At this time, the element width W, the element length L, the specific resistance ρ, the excitation frequency ω, the magnetic permeability μ in the element width direction, and the magnitude | Z | , The following (Equation 1) holds.

[0029]

(Equation 1) From (Equation 1), when the element width W, element length L, specific resistance ρ, and excitation frequency ω of the magnetic sensing part are constant, the magnitude | Z | of the impedance of the magnetic sensing part is in the element width direction. Is proportional to the half of the magnetic permeability μ. When an alternating current is applied in the element longitudinal direction and an external magnetic field is applied in the element longitudinal direction of the magneto-sensitive section which is excited in the element width direction, the magnetic permeability μ of the magneto-sensitive section in the element width direction changes. Then, the magnitude | Z | of the impedance of the magnetic sensing portion changes. The external magnetic field applied to the magnetic sensing unit is detected by measuring the change in the magnitude | Z | of the impedance of the magnetic sensing unit.

As the aspect ratio W / L decreases, the rate of change of the magnitude | Z | of the impedance with respect to the change of the magnetic permeability μ in the element width direction increases. That is, the change in the magnitude of the output voltage drawn from both ends of the magneto-sensitive portion increases, and the magnetic field detection sensitivity of the magneto-impedance effect element improves.

The element width W and the element length L of the magneto-sensitive portion are
Is preferably 0.05 or less, and more preferably, the element width W of the magneto-sensitive portion.
And the element length L (aspect ratio) W / L is 0.03
It is as follows.

When the magnetic sensing portion is formed in a U-shape or a broken shape, the sum of the lengths of the magnetic sensing portion in the element longitudinal direction is the element length L. The element longitudinal direction at this time is an extension direction of the longest linear portion in the magneto-sensitive portion, and coincides with a direction perpendicular to the excitation direction of the magnetic field generated by the driving alternating current.

Further, in the present invention, the soft magnetic body portion has a single magnetic domain structure or a multi-domain structure, and when the component of the magnetic moment in the element longitudinal direction and the component in the element width direction are compared in each magnetic domain, It is preferable that the total area of the magnetic domain having a larger component in the element longitudinal direction is equal to the total area of the magnetic domain having a larger component in the element width direction.

The soft magnetic body portion has a single magnetic domain structure or a multi-domain structure, and when the component of the magnetic moment in the element longitudinal direction and the component in the element width direction are compared in each magnetic domain, the component in the element longitudinal direction is obtained. When the total area of the magnetic domain having a larger component is equal to the total area of the magnetic domain having a larger component in the element width direction, the direction of the magnetic anisotropy of the soft magnetic body as a whole is substantially equal. Become a unilateral state

That is, it is difficult for the magnetic moment of the soft magnetic body to be fixed in a certain direction, and when the magnetically sensitive part having the soft magnetic body is excited by an alternating current,
It becomes easy to change the direction of the magnetic moment of the soft magnetic body. That is, the magnetic permeability μ of the soft magnetic body in the element width direction increases, and when the external magnetic field is not applied, the magnetic permeability μ of the soft magnetic body in the element width direction takes a maximum value. When the magnetic permeability μ of the soft magnetic portion in the element width direction has the maximum value, the magnitude Z of the impedance of the soft magnetic portion becomes maximum, and the output voltage from both ends of the magnetic sensing portion also becomes maximum. That is, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magneto-sensitive portion approaches zero.

Alternatively, in the present invention, the soft magnetic body constituting the magnetically sensitive portion has a single magnetic domain structure or a multi-magnetic domain structure, and in each magnetic domain, the component of the magnetic moment in the element longitudinal direction and the component in the element width direction. It is preferable that the total area of magnetic domains having a larger component in the element longitudinal direction is larger than the total area of magnetic domains having a larger component in the element width direction.

In each magnetic domain of the soft magnetic portion, when the component of the magnetic moment in the element longitudinal direction and the component in the element width direction are compared, the total area of the magnetic domain in which the component in the element longitudinal direction is larger is as follows. Even when the component in the element width direction is larger than the total area of the large magnetic domains, the direction of the magnetic anisotropy of the soft magnetic material part constituting the magneto-sensitive part is brought to a state close to an isotropic state as a whole. A magneto-impedance effect element having a magnetically sensitive portion having a magnetic domain structure in which the total area of magnetic domains having a larger component in the element width direction and the total area of magnetic domains having a larger component in the element longitudinal direction are equal. Equivalent magnetic field detection sensitivity can be obtained.

When the direction of the magnetic anisotropy of the soft magnetic material part constituting the magnetic sensing part is in a state close to an isotropic state as a whole, the external direction slightly extends in the element longitudinal direction of the magnetic sensing part. By simply applying a magnetic field, the direction of the magnetic anisotropy of the soft magnetic material part can be made substantially isotropic as a whole,
The magnetic permeability μ of the magneto-sensitive portion in the element width direction can be maximized, and the output voltage from both ends of the magneto-sensitive portion can be maximized. That is, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magneto-sensitive portion can be reduced.

Further, when the magneto-impedance effect element of the present invention has a magnetic material for applying a bias magnetic field in a direction parallel to the element longitudinal direction of the magneto-sensitive part, the manufacturing process can be simplified and the size can be reduced. This is preferable because power consumption can be reduced and power consumption can be reduced.

The magnetic sensing part of the magneto-impedance effect element needs to have a ferromagnetic material having soft magnetic characteristics. Further, the magnetic permeability μ must be high in a high frequency range of 1 MHz to several hundred MHz. Further, it is preferable that the magnetostriction constant λ be small so that the soft magnetic material is not stressed by the external magnetic field (magnetic field component of the broadcast radio wave) and the magnetic characteristics are not deteriorated.

Since the soft magnetic material is formed as a thin film magnetic material having such properties, it is preferable that the soft magnetic material is formed as a microcrystalline soft magnetic alloy thin film as described below.

1. A microcrystalline soft magnetic alloy thin film whose composition formula is represented by Fe _h M _i O _j and which mainly has an amorphous structure.

Where M is Ti, Zr, Hf, V, N
one or two selected from b, Ta, W and a rare earth element
H, i, j are at% and 45 ≦ h
≦ 70, 5 ≦ i ≦ 30, 10 ≦ j ≦ 40, h + i + j =
What satisfies 100 relationships.

Fe is for obtaining a large saturation magnetic flux density Bs, and M is for combining with O to increase the specific resistance ρ. When h, i, and j are within the above ranges, a soft magnetic alloy having a large saturation magnetic flux density Bs, specific resistance ρ, and magnetic permeability μ can be obtained. When h, i, and j are out of the above ranges, soft magnetic properties can be obtained. Deteriorates.

When the element M is one or more elements selected from the rare earth elements in the above composition, h and j are at% and 50 ≦ h ≦ 70 and 10 ≦ j ≦ 3.
More preferably, it is 0.

2. Composition _{formula, (Co 1-c T c} ) x M y X z O w
A microcrystalline soft magnetic alloy thin film represented by Where the element T is
An element containing one or both of Fe and Ni, and the element M is composed of Ti, Zr, Hf, V, Nb, T
a, Cr, Mo, Si, P, C, W, B, Al, Ga,
X is one or more elements selected from Ge and rare earth elements, and X is Au, Ag, Cu, Ru, Rh, O
one or more elements selected from s, Ir, Pt, and Pd, and the composition ratio is such that c is 0 ≦ c ≦ 0.7,
x, y, z, w are at%, 3 ≦ y ≦ 30, 0 ≦ z ≦ 2
Those satisfying the relationship of 0, 7 ≦ w ≦ 40, 20 ≦ y + z + w ≦ 60, and the balance being x.

In the soft magnetic alloy, an amorphous phase containing a large amount of an oxide of the element M is mixed with a microcrystalline phase mainly composed of Co and the element T. It is more preferable to have a structure including the same.

3. Composition _{formula, T 100-defg X d M} e Z f Q
_g , bcc-Fe, bcc-FeCo, bcc
-A microcrystalline soft magnetic alloy thin film mainly composed of one or more crystal grains of Co.

The element T is an element containing one or both of Fe and Co, and the element X is S
i is an element containing one or both of Al, and the element M is Ti, Zr, Hf, V, Nb, Ta,
One or more elements selected from Mo and W, the element Z is an element containing one or both of C and N, and Q is Cr, Re, Ru, Rh, N
one or more elements selected from i, Pd, Pt, and Au, where d, e, f, and g are at% and 0 ≦ d ≦ 2
5, 1 ≦ e ≦ 10, 0.5 ≦ f ≦ 15, 0 ≦ g ≦ 10.

When d, e, f, and g are within the above ranges, a soft magnetic alloy thin film having a large magnetic permeability μ, a low coercive force Hc, and a small magnetostriction constant λ can be obtained.

4. The composition formula is T _100-pqefg Si _p Al
represented by _{q M e Z f Q g,} bcc-Fe, bcc-FeC
o, a microcrystalline soft magnetic alloy thin film mainly composed of one or more crystal grains of bcc-Co.

The element T is an element containing one or both of Fe and Co, and the element M is
i, Zr, Hf, V, Nb, Ta, Mo, W are one or more elements selected from the group consisting of C, N
Element containing one or both of
Are Cr, Re, Ru, Rh, Ni, Pd, Pt, Au
One or more elements selected from the group consisting of p,
q, e, f, and g are at%, 8 ≦ p ≦ 15, 0 ≦ q ≦ 1
0, 1 ≦ e ≦ 10, 0.5 ≦ f ≦ 15, and 0 ≦ g ≦ 10.

When p, q, e, f, and g are within the above ranges, the magnetic permeability μ is large, the coercive force Hc is low, and the magnetostriction constant λ
A soft magnetic alloy having a small size can be obtained.

Further, the magnetic sensing portion may be formed as having an amorphous soft magnetic alloy thin film or ribbon as described below.

5. The composition formula is (Fe _1-a Co _a ) _100-xy
(Si _{1-b B b)} amorphous soft magnetic alloy thin film or ribbon represented by _x M _y.

Here, M is an element containing one or both of Cr and Ru, and a, which represents a composition ratio,
b satisfies the relationship of 0.05 ≦ a ≦ 0.1, 0.2 ≦ b ≦ 0.8, and x and y satisfy the relationship of 10 ≦ x ≦ 35 and 0 ≦ y ≦ 7 at%.

The above (Fe _1-a Co _a ) _100-xy (Si _1-b B
_{b) x} in M _y based soft magnetic alloy thin film or ribbons, a 0.0
Exceeding the range of 5 ≦ a ≦ 0.1 is not preferable because the magnetostriction increases. On the other hand, if b exceeds the range of 0.2 ≦ b ≦ 0.8, it becomes difficult to make the film amorphous, which is not preferable. Further, when x exceeds the range of 10 ≦ x ≦ 35, it becomes difficult to form an amorphous state, which is not preferable. If x> 35, the magnetic properties deteriorate, which is not preferable.

6. Composition formula, Co _l Ta _m expressed by Hf _n, amorphous soft magnetic alloy thin film was amorphous structure mainly.

Here, l, m and n are at% and 70 ≦ l
≦ 90, 5 ≦ m ≦ 21, 6.6 ≦ n ≦ 15, 1 ≦ m / n
Those satisfying the relationship of ≦ 2.5.

[0060] In soft magnetic alloy thin film of the Co _l Ta _m Hf _n system, the saturation magnetic flux density Bs is dependent on the content of Co, in order to obtain a high saturation magnetic flux density Bs, it is 70 ≦ l is necessary. However, if l> 90, the specific resistance ρ becomes low, which is not preferable.

Ta and Hf are elements for obtaining soft magnetic properties, and when 5 ≦ m ≦ 21 and 6.6 ≦ n ≦ 15, soft magnetic density Bs and specific resistance ρ are increased. Material can be obtained. Hf is Co
It is also an element for eliminating the negative magnetostriction constant λ generated in the -Ta system. The magnetostriction constant λ is determined by the Ta content and Hf
Depends on the content ratio, and if it is within the range of 1 ≦ m / n ≦ 2.5, the magnetostriction constant λ can be satisfactorily eliminated.

7. Composition formula, amorphous soft magnetic alloy thin film mainly composed of amorphous structure represented by Co _a Zr _b Nb _c.

However, a, b, and c are at%, and 78 ≦ a
≦ 91, 0.5 ≦ b / c ≦ 0.8.

The saturation magnetic flux density Bs depends on the Co concentration.
In order to increase Bs, it is necessary to satisfy 78 ≦ a ≦ 91. When a> 91, the corrosion resistance is lowered and an amorphous structure is hardly formed, and crystallization starts, which is not preferable. Further, if a <78, the ratio of adjacent Cos decreases, and it becomes difficult to exhibit soft magnetic characteristics, which is not preferable. The magnetic permeability μ also depends on the Co concentration,
It shows a high value in the range of ≦ a ≦ 91.

Further, the method for manufacturing a magneto-impedance effect element of the present invention comprises the steps of:
A step of alternately forming a soft magnetic thin film and a conductive thin film having a lower specific resistance than the soft magnetic thin film; and (b) a step of pattern-forming a magnetically sensitive portion from the multilayer film formed in the step (a). And (c) heat-treating the magnetically sensitive part in a static magnetic field in the element width direction of the magnetically sensitive part.

Alternatively, the method of manufacturing a magneto-impedance effect element according to the present invention comprises: (d) alternately forming a soft magnetic thin film and a conductive thin film having a lower specific resistance than the soft magnetic thin film on a substrate made of a non-magnetic material. Forming a film; (e) heat treating the multilayer film formed in the step (d) in a static magnetic field; and (f) forming the multilayer film so that the direction of the static magnetic field is the element width direction. Forming a magnetically sensitive portion by patterning a film.

In the step (a) or (d), the soft magnetic thin film may be formed in a static magnetic field in the same direction as the static magnetic field in the step (c) or (e). preferable.

Further, the uppermost layer and the lowermost layer of the multilayer film are the soft magnetic thin films, and the uppermost soft magnetic thin film and the lowermost soft magnetic thin film are magnetically bonded at least at the end in the element width direction. They may be combined.

When the multilayer film is patterned, a photoresist is laminated on the multilayer film, and the multilayer film is etched by a wet etching method, so that the element width direction dimension of the upper surface is smaller than that of the bottom surface. It is preferable to form a magnetic sensing portion shorter than the element width direction dimension.

Further, when forming the multilayer film, the method includes a step of forming an insulating layer between the soft magnetic thin film and the conductive thin film, and forming an electrode portion connected only to the conductive thin film. Is preferred.

The magnetic sensing part of the magneto-impedance effect element is
(A) or (d) in order to form a ferromagnetic thin film having a high magnetic permeability μ in a high frequency range of 1 MHz to several hundred MHz and a soft magnetic characteristic having a small magnetostriction constant λ.
In the step (b), the soft magnetic thin film is preferably formed as a microcrystalline soft magnetic alloy thin film as described below.

1. A microcrystalline soft magnetic alloy thin film whose composition formula is represented by Fe _h M _i O _j and which mainly has an amorphous structure.

Where M is Ti, Zr, Hf, V, N
one or two selected from b, Ta, W and a rare earth element
H, i, j are at% and 45 ≦ h
≦ 70, 5 ≦ i ≦ 30, 10 ≦ j ≦ 40, h + i + j =
What satisfies 100 relationships.

2. Composition _{formula, (Co 1-c T c} ) x M y X z O w
A microcrystalline soft magnetic alloy thin film represented by Where the element T is
An element containing one or both of Fe and Ni, and the element M is composed of Ti, Zr, Hf, V, Nb, T
a, Cr, Mo, Si, P, C, W, B, Al, Ga,
X is one or more elements selected from Ge and rare earth elements, and X is Au, Ag, Cu, Ru, Rh, O
one or more elements selected from s, Ir, Pt, and Pd, and the composition ratio is such that c is 0 ≦ c ≦ 0.7,
x, y, z, w are at%, 3 ≦ y ≦ 30, 0 ≦ z ≦ 2
Those satisfying the relationship of 0, 7 ≦ w ≦ 40, 20 ≦ y + z + w ≦ 60, and the balance being x.

In the soft magnetic alloy, an amorphous phase containing a large amount of an oxide of the element M is mixed with a microcrystalline phase mainly composed of Co and the element T. It is more preferable to have a structure including the same.

3. Composition _{formula, T 100-defg X d M} e Z f Q
_g , bcc-Fe, bcc-FeCo, bcc
-A microcrystalline soft magnetic alloy thin film mainly composed of one or more crystal grains of Co.

The element T is an element containing one or both of Fe and Co, and the element X is S
i is an element containing one or both of Al, and the element M is Ti, Zr, Hf, V, Nb, Ta,
One or more elements selected from Mo and W, the element Z is an element containing one or both of C and N, and Q is Cr, Re, Ru, Rh, N
one or more elements selected from i, Pd, Pt, and Au, where d, e, f, and g are at% and 0 ≦ d ≦ 2
5, 1 ≦ e ≦ 10, 0.5 ≦ f ≦ 15, 0 ≦ g ≦ 10.

4. The composition formula is T _100-pqefg Si _p Al
represented by _{q M e Z f Q g,} bcc-Fe, bcc-FeC
o, a microcrystalline soft magnetic alloy thin film mainly composed of one or more crystal grains of bcc-Co.

The element T is an element containing one or both of Fe and Co, and the element M is
i, Zr, Hf, V, Nb, Ta, Mo, W are one or more elements selected from the group consisting of C, N
Element containing one or both of
Are Cr, Re, Ru, Rh, Ni, Pd, Pt, Au
One or more elements selected from the group consisting of p,
q, e, f, and g are at%, 8 ≦ p ≦ 15, 0 ≦ q ≦ 1
0, 1 ≦ e ≦ 10, 0.5 ≦ f ≦ 15, and 0 ≦ g ≦ 10.

Alternatively, in the step (a), the step (d) or the step (g), the soft magnetic thin film or the soft magnetic ribbon may be replaced with an amorphous soft magnetic alloy thin film or a ribbon as described below. It may be formed.

5. Composition formula, Co _l Ta _m expressed by Hf _n, amorphous soft magnetic alloy thin film was amorphous structure mainly.

Where l, m and n are at% and 70 ≦ l
≦ 90, 5 ≦ m ≦ 21, 6.6 ≦ n ≦ 15, 1 ≦ m / n
Those satisfying the relationship of ≦ 2.5.

6. Composition formula, amorphous soft magnetic alloy thin film mainly composed of amorphous structure represented by Co _a Zr _b Nb _c.

Where a, b, and c are at%, and 78 ≦ a
≦ 91, 0.5 ≦ b / c ≦ 0.8.

Further, the method for manufacturing a magneto-impedance effect element of the present invention comprises the steps of: (g) forming a soft magnetic ribbon by injecting a molten alloy of a soft magnetic material onto a cooling roll and quenching the contact; h) a step of forming a conductive thin film having a lower specific resistance than the soft magnetic ribbon on at least one surface of the soft magnetic ribbon; and (i) a soft magnetic ribbon formed by the step (h). To form a pattern with a predetermined value of an element width W to an element length L (aspect ratio) W / L, and (j) the conductive thin film formed by the step (i). Laminating the soft magnetic ribbon on which the soft magnetic ribbons are laminated so that the soft magnetic ribbons and the conductive thin films are alternately laminated on the substrate; Heat treating in a magnetic field.

In the steps (h) and (J), an insulating layer is formed between the soft magnetic ribbon and the conductive thin film, and after the step (j), the conductive layer is formed. It is preferable to include a step of forming an electrode portion connected to only the conductive thin film.

Further, in the step (a), the step (d) or the step (g), the soft magnetic thin film or the soft magnetic ribbon is represented by a composition formula (Fe _1-a Co _a ) _100-xy ( Si _1-b
B _b) it may be formed as an amorphous soft magnetic alloy thin film or ribbon represented by _x M _y.

Here, M is an element containing one or both of Cr and Ru, and a, which represents a composition ratio,
b is 0.05 ≦ a ≦ 0.1, 0.2 ≦ b ≦ 0.8, and x and y are at% and satisfy the relation of 10 ≦ x ≦ 35 and 0 ≦ y ≦ 7. .

After the magneto-impedance effect element is formed, when an external magnetic field is applied while applying a drive AC current in the longitudinal direction of the magneto-sensitive section, the output voltage from both ends of the magneto-sensitive section is maximized. The ratio of the element width W to the element length L (aspect ratio) W / L is set so that the absolute value of the magnitude of the external magnetic field is 400 (A / m) or less. Preferably, it is formed.

Further, the aspect ratio of the magnetic sensing part is set to 0.1.
It is preferable to set the following.

[0091]

FIG. 1 is a perspective view showing a magneto-impedance effect element according to a first embodiment of the present invention.

The magneto-impedance effect element M shown in FIG.
A soft magnetic thin film 22 as a soft magnetic material portion, a conductive thin film 23 as a conductive material portion, and a soft magnetic thin film 24 are sequentially laminated on a substrate 21 made of a non-magnetic material such as alumina titanium carbide. The magnetic part 25 and the electrode parts 26, 26 formed of a conductive material such as Cu, Ni, Ti, and Cr at both ends of the magnetic sensing part 25.
The magnetic sensing portion 25 is formed in a substantially rectangular or linear pattern. Further, the magnetic sensing part 25 may be formed in a U-shape or a zigzag shape.

In FIG. 1, the electrode portions 26 are formed at both ends of the magneto-sensitive portion 25 in the longitudinal direction of the element, but the electrode portions 26 are located near both ends of the upper surface of the soft magnetic thin film 24. A conductive material such as Cu may be stacked thereover.

The electrode portion 2 is connected to the magneto-impedance effect element M.
A driving alternating current is applied in the element longitudinal direction (Y direction) from 6, 26 to excite the magnetosensitive portion 25 in the element width direction (X direction).
In this state, when the external magnetic field Hex is applied in the element longitudinal direction, the impedance of the magnetic sensing unit 25 changes. The change in impedance of the magnetic sensing unit 25 is extracted as a change in voltage between the electrode units 26, 26.

Here, the longitudinal direction of the element coincides with the direction perpendicular to the exciting direction of the magnetic field generated by the driving alternating current.

When the magnetic sensing part 25 is formed in a U-shape or a broken shape, the extension direction of the longest straight line portion in the magnetic sensing part is the element longitudinal direction, and this direction is the driving AC current. In the direction perpendicular to the direction of excitation of the magnetic field generated by the

Note that a protective layer made of an insulating material may be formed on the magnetic sensing portion 25. The soft magnetic thin films 22 and 24
For example, if the composition formula is Fe _71.4 Al _5.8 Si _13.1 Hf _3.3 C
_4.5 A microcrystalline soft magnetic alloy thin film represented by Ru _1.9 (at%) mainly composed of bcc-Fe crystal grains and having HfC crystal grains around bcc-Fe and having an average crystal grain size of 5 to 30 nm. is there.

A TXM-ZQ system other than this composition (the element T is an element containing one or both of Fe and Co, and the element X is one of Si and Al Alternatively, it is an element containing both, and the element M is Ti, Z
r, Hf, V, Nb, Ta, Mo, W are one or more elements selected from the group consisting of C and N; C
one or more elements selected from the group consisting of r, Re, Ru, Rh, Ni, Pd, Pt, and Au), a microcrystalline soft magnetic alloy thin film, and a Co—T—M—X—O system (element T is , Fe, N
element containing one or both of i,
Element M is Ti, Zr, Hf, V, Nb, Ta, Cr,
One or more elements selected from Mo, Si, P, C, W, B, Al, Ga, Ge and rare earth elements;
X is Au, Ag, Cu, Ru, Rh, Os, Ir, P
one or two or more elements selected from t and Pd), bcc-Fe, bcc-FeCo, bcc
A microcrystalline soft magnetic alloy thin film comprising a crystalline phase composed of Co or the like and having an average crystal grain size of 10 to 30 nm and an amorphous phase containing an oxide of M, wherein the amorphous phase occupies 50% or more of the entire structure; Or Fe-MO system (M is Ti, Zr, Hf, V, N
one or two selected from b, Ta, W and a rare earth element
Element), a crystal phase mainly composed of bcc-Fe and having an average crystal grain size of 10 to 30 nm, and an amorphous phase containing M oxide. The soft magnetic thin films 22 and 24 may be formed as a microcrystalline soft magnetic alloy thin film occupying 50% or more.

Alternatively, an amorphous soft magnetic alloy thin film of a Fe—Co—Si—BM system (M is an element containing one or both of Cr and Ru), a Co—Ta—H
The soft magnetic thin films 22 and 24 may be formed as an f-based amorphous soft magnetic alloy thin film or a Co-Zr-Nb-based amorphous soft magnetic alloy thin film.

The conductive thin film 23 is made of Cu, Ni, Ti, C
It is formed of a conductive material such as r. The material used to form the conductive thin film 23 is a soft magnetic thin film 2.
Any material may be used as long as it has a lower specific resistance than 2,24. For example, a ferromagnetic material containing Fe and Co or an antiferromagnetic material such as NiO and CoO may be used. However, the specific resistance of the material used for forming the conductive thin film 23 is preferably a material having a specific resistance of 1/10 or less of the specific resistance of the material used for forming the soft magnetic thin films 22 and 24.

In the present embodiment, the magnetic sensing part 25 is formed as the soft magnetic thin films 22, 24 and the conductive thin film 23 are alternately laminated. When the soft magnetic thin films 22 and 24 made of a soft magnetic material and the conductive thin film 23 formed of a material having a lower specific resistance than the soft magnetic material have a structure in contact with each other, the magnetic sensing unit 25 is driven. When an AC current is applied, the drive AC current flows into the soft magnetic thin films 22, 24 and the conductive thin film 23 separately. As a result, the DC resistance value of the magnetic sensing unit 25 when the driving AC current flows is reduced, and the power consumption of the magneto-impedance effect element can be reduced.

Further, since the magnetic sensing portion 25 has a structure in which the soft magnetic thin films 22 and 24 having a high magnetic permeability and the conductive thin film 23 having a high conductivity are in contact with each other, the drive flowing through the magnetic sensing portion is performed. The skin thickness of the alternating current is reduced, and a large magneto-impedance effect can be generated. Therefore, a sufficient amount of change in the output voltage with respect to the magnetic field can be obtained even at a low drive voltage.

FIG. 2 is a sectional view of a magnetic sensing part of a magneto-impedance effect element according to a second embodiment of the present invention.

The magneto-impedance effect element shown in FIG. 2 has a soft magnetic thin film 32 as a soft magnetic material, a conductive thin film 33 as a conductive material, and a soft magnetic thin film 32 on a substrate 21 made of a nonmagnetic material such as alumina titanium carbide. It has a magnetic sensing part 35 formed by sequentially laminating magnetic thin films 34. In the present embodiment, the uppermost soft magnetic thin film 34 and the lowermost soft magnetic thin film 32 of the magnetic sensing unit 35 are magnetically coupled at the ends in the element width direction. When a driving AC current is passed, a closed orbiting magnetic field can be generated in the soft magnetic thin film 34 and the soft magnetic thin film 32.

FIG. 3 is a sectional view of a magnetic sensing part of a magneto-impedance effect element according to a third embodiment of the present invention.

The magneto-impedance effect element shown in FIG. 3 has a soft magnetic thin film 42 as a soft magnetic material, a conductive thin film 43 as a conductive material, and a soft magnetic thin film 42 on a substrate 21 made of a nonmagnetic material such as alumina titanium carbide. It has a magnetic sensing portion 45 formed by sequentially laminating magnetic thin films 44. In the present embodiment, as the magnetic sensing part 45 moves away from the surface 21a of the substrate 21, the dimension in the element width direction (Y direction) is gradually reduced. Therefore, the film stress can be dispersed, the magnetic sensing part 45 can be prevented from peeling off from the substrate, and the magnetic sensing part 45 can be maintained in a stable shape.

The sectional shape of the magnetic sensing part 45 is not limited to the shape shown in FIG. 3, and the dimension of the top surface 45a of the magnetic sensing part 45 in the element width direction is the dimension of the bottom surface 45b of the magnetic sensing part 45 in the element width direction. It should just be shorter. For example, both ends of the magneto-sensitive portion 45 in the element width direction may be formed in a step shape.

FIG. 4 is a sectional view of a magnetic sensing part of a magneto-impedance effect element according to a fourth embodiment of the present invention.

The magneto-impedance effect element of the present invention
The soft magnetic thin film and the conductive thin film do not necessarily have to be sequentially stacked in the vertical direction.

For example, as shown in FIG. 4, a soft magnetic thin film 52, a conductive thin film 53, and a soft magnetic thin film 54 are formed on the same surface 21a of a substrate 21 made of a nonmagnetic material such as alumina titanium carbide. The formed soft magnetic thin film 52
The magneto-impedance effect element may have a magneto-sensitive portion 55 having a structure in which the conductive thin film 53 and the conductive thin film 53 are in contact with each other, and the conductive thin film 53 and the soft magnetic thin film 54 are in contact with each other.

Even in the magneto-impedance effect element having the magnetic sensing part 55 shown in FIG.
The current flows inside the conductive thin film 53 and the current flowing inside the conductive thin film 53. As a result, the DC resistance value of the magnetic sensing unit 55 when the driving AC current flows is reduced, and the power consumption of the magneto-impedance effect element can be reduced.

Further, since the magnetic sensing portion 55 has a structure in which the soft magnetic thin films 52 and 54 having high magnetic permeability and the conductive thin film 53 having high conductivity are in contact with each other, the driving force flowing through the magnetic sensing portion 55 is provided. The skin thickness of the alternating current is reduced, and a large magneto-impedance effect can be generated. Therefore, a sufficient amount of change in the output voltage with respect to the magnetic field can be obtained even at a low drive voltage.

FIG. 5 is a sectional view of a magnetic sensing part of a magneto-impedance effect element according to a fifth embodiment of the present invention.

In the present invention, any number of layers of the soft magnetic thin film and the conductive thin film of the magnetic sensing portion may be stacked.

For example, as shown in FIG. 5, a soft magnetic thin film 62 as a soft magnetic material, a conductive thin film 63 as a conductive material, and a soft magnetic thin film are formed on a substrate 21 made of a non-magnetic material such as alumina titanium carbide. A magneto-impedance effect element having a magnetically sensitive portion 67 formed by sequentially laminating a conductive thin film 64, a conductive thin film 65, and a soft magnetic thin film 66 may be used.

Note that the uppermost soft magnetic thin film 66 and the lowermost soft magnetic thin film 62 may be magnetically coupled at the end in the element width direction. Also, the magnetic sensing part 67 is
May be formed so that the dimension in the element width direction (Y direction) gradually decreases as the distance from the surface 21a increases.

FIG. 6 is a sectional view of a magnetic sensing part of a magneto-impedance effect element according to a sixth embodiment of the present invention.

In the present invention, the conductive thin film of the magneto-sensitive portion does not necessarily have to be sandwiched by a plurality of soft magnetic thin films.

For example, as shown in FIG. 6, there is provided a magnetically sensitive portion 74 in which only a soft magnetic thin film 72 and a conductive thin film 73 are sequentially laminated on a substrate 21 made of a nonmagnetic material such as alumina titanium carbide. The magneto-impedance effect element described above may be used.

[0120] At both ends of the magnetic sensing portions 35, 45, 55, 67, and 74, electrode portions for applying a drive AC current in the element longitudinal direction (Y direction) of the magnetic sensing portions are made of Cu, Ni, or Ni. T
It is formed of a conductive material such as i or Cr. Magnetic sensing part 3
5, 45, 55, 67, and 74 are patterned in a substantially rectangular or linear shape. Or, the magnetic sensing unit 35,
45, 55, 67, and 74 may be formed in a U shape or a zigzag shape.

Magnetic sensing units 35, 45, 55, 67, and 74
Is applied in the element longitudinal direction (Y direction) to excite in the element width direction (X direction). In this state, the external magnetic field H
ex is applied in the longitudinal direction of the element, and the
The impedances of 5, 55, 67 and 74 change. The impedance change of the magnetic sensing units 35, 45, 55, 67, and 74 is extracted as a change in voltage between the electrode units.

Note that a protective layer made of an insulating material may be formed on the magnetic sensing portions 35, 45, 55, 67, and 74.

FIG. 7 is a perspective view of a magneto-impedance effect element according to a seventh embodiment of the present invention, and FIG.
FIG. 8 is a cross-sectional view of the magneto-impedance effect element of FIG.

In the magneto-impedance effect element shown in FIGS. 7 and 8, a soft magnetic thin film 81, an insulating layer 82 made of an insulating material, a conductive thin film 83, an insulating film 82 are formed on a substrate 21 made of a nonmagnetic material such as alumina titanium carbide. A layer 84 and a soft magnetic thin film 85 are sequentially laminated to form a magnetically sensitive portion 86.

The soft magnetic thin film 81 and the conductive thin film 83 are electrically insulated by the insulating layer 82. The conductive thin film 83 and the soft magnetic thin film 85 are electrically insulated by the insulating layer 84.

At both ends of the magnetic sensing portion 86, the conductive thin film 83 is provided.
Are formed of a conductive material such as Cu, Ni, Ti, or Cr for applying a drive AC current in the element longitudinal direction (Y direction). The electrode portions 87, 87 are connected only to the conductive thin film 83. The soft magnetic thin film 81 and the electrode portions 87, 87 are electrically insulated by the insulating layer 82. Further, the soft magnetic thin film 85 and the electrode portions 87, 87
Are electrically insulated by the insulating layer 84. Therefore, the driving alternating current flows only through the conductive thin film 83.

Element longitudinal direction of conductive thin film 83 (Y direction)
, And a driving AC current is applied to the element to excite it in the element width direction (X direction). When the external magnetic field Hex is applied in the element longitudinal direction in this state, the impedance of the magnetic sensing unit 86 changes. A change in impedance of the magnetic sensing unit 86 is extracted as a change in voltage between the electrode units.

When the driving AC current is caused to flow only to the conductive thin film 83 and not to the soft magnetic thin films 81 and 85, an exciting magnetic field by the driving AC current can be efficiently generated, and a more remarkable magnetic impedance can be obtained. It is possible to bring out the effect.

The magnetic sensing portion 86 is formed in a substantially rectangular or linear pattern. Alternatively, the magnetic sensing portion 86 may be formed in a U-shape or a zigzag shape.

FIG. 9 is a graph showing the relationship between the aspect ratio of the magneto-sensitive portion of the magneto-impedance effect element and the magnetic field detection sensitivity. In the graph of FIG. 9, the element length L of the magnetic sensing part is 4
mm or 6 mm, and the aspect ratio W / L of the magneto-sensitive portion was changed by changing the element width W. As is clear from FIG. 9, the aspect ratio W / L of the magnetosensitive part is 0.1.
It can be seen that the magnetic field detection sensitivity of the magneto-impedance effect element is improved below. In particular, when the element length L of the magneto-sensitive section is 6 mm, if the aspect ratio W / L of the magneto-sensitive section becomes about 0.08 or less, the magnetic field detection sensitivity of the magneto-impedance effect element can be further sharply improved. Understand.

When the magneto-sensitive portion is formed in a U-shape or a serpentine shape, the sum of the lengths of the magneto-sensitive portion in the element longitudinal direction is the element length L.

In the present embodiment, the magnetosensitive portion 25 is formed, for example, with an element width W of 0.10 mm and an element length L of 6 mm. At this time, the aspect ratio of the magneto-sensitive portion 25 of the magneto-impedance effect element M is W / L = 0.0
Seventeen.

If the magneto-impedance effect element M shown in FIG. 1 has an element length of 6 mm and an aspect ratio of 0.017, it can be seen from the graph of FIG. 9 that about 2.5 (mV · m / A) is obtained.
(About 200 (mV / Oe)).

FIG. 10 shows the aspect ratio (W / L) of the magneto-sensitive portion of the magneto-impedance effect element and the absolute value (H) of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magneto-sensitive portion.
It is a graph which shows the relationship with p).

From the graph of FIG. 10, when the aspect ratio (W / L) of the magneto-sensitive portion of the magneto-impedance effect element is reduced, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magneto-sensitive portion It can be seen that (Hp) also becomes smaller. In the graph of FIG. 3, the element length of the magnetic sensing unit is fixed to 4 mm or 6 mm, and the aspect ratio of the magnetic sensing unit is changed by changing the element width.

For example, when the element length of the magneto-sensitive part is 6 mm and the aspect ratio (W / L) is set to about 0.1 or less,
The absolute value (Hp) of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magnetic sensing unit is 320 (A / m) (4
(Oe)) Also, the element length of the magnetic sensing part is 4 m.
m, the absolute value (Hp) of the magnitude of the external magnetic field that maximizes the output voltage is 320 (A / m) (4 (Oe) when the aspect ratio (W / L) is set to about 0.1 or less. ))

When the element length of the magnetic sensing part is 6 mm,
When the aspect ratio (W / L) is about 0.05 or less, the absolute value (Hp) of the magnitude of the external magnetic field that maximizes the output voltage
Is 160 (A / m) (2 (Oe)) or less.

The magneto-sensitive section 25 of the magneto-impedance effect element M of the present embodiment shown in FIG.
Since the aspect ratio is 0.017, from the graph of FIG. 10, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage is approximately 0 to 24 (A / m) (0.3 (Oe)). It turns out that it is in the range.

FIG. 11 is a conceptual diagram for explaining the magneto-impedance effect characteristics of the magneto-impedance effect element according to the present embodiment.

In a state where a driving alternating current is applied from the electrodes 26 of the magneto-impedance effect element M to both ends of the magneto-sensitive section 25 in FIG. Apply. When the output voltage Emi is measured while changing the magnitude of the applied external magnetic field Hex, a graph as shown in FIG. 11 is obtained.

The conceptual diagram showing the magneto-impedance effect characteristic of FIG. 11 has a bimodal shape with the point indicating the value of the output voltage Emi when the magnitude of the external magnetic field Hex is Hp ₊ or Hp ₋ as a vertex. I have. In addition, the magnitudes of the absolute values of Hp ₊ and Hp ₋ are almost the same, approximately 0 to 24 (A /
m) (0.3 (Oe)).

Referring to FIG. 11, as the magnitude of the external magnetic field Hex approaches Hp ₊ or Hp ₋ , the output voltage Emi increases.
Change rate is increasing. That is, the external magnetic field He
The detection sensitivity of x becomes good when the magnitude of the external magnetic field Hex is near Hp ₊ or Hp ₋ .

When the absolute value of the magnitude of Hp ₊ or Hp ₋ is approximately 0 to 24 (A / m) (0.3 (Oe)), the detection sensitivity of the external magnetic field Hex near the external magnetic field Hex = 0 is reduced. In order to improve the magnetic field, the magnitude of the bias magnetic field applied in the element longitudinal direction of the magnetic sensing unit 25 is, for example, H _B =
0 to 80 (A / m) (1 (Oe)) is sufficient. In the examples described later, a graph of the magneto-impedance effect characteristics of the magneto-impedance effect element based on the actually measured values will be described.

Incidentally, the absolute value of the magnitude of Hp ₊ or Hp ₋ is 400 (A / m) (5 (Oe)) or less, preferably 3 (Oe).
20 (A / m) (4 (Oe)) or less, more preferably 1
If it is 60 (A / m) (2 Oe) or less, the magnitude of the bias magnetic field applied to the magneto-sensitive portion 25 in the element longitudinal direction is 400
(A / m) (5 (Oe)) or less, preferably 320 (A
/ M) (4 (Oe)) or less, more preferably 160 (A)
/ M) (2Oe) or less.

When the magnitude of the necessary bias magnetic field applied in the element longitudinal direction of the magneto-sensitive portion 25 can be reduced to 400 (A / m) or less, the hard magnetic material formed around the magneto-sensitive portion 25 can be formed. Alternatively, a magnetic field generated from a magnetic film made of a hard magnetic material or an antiferromagnetic material formed on the magnetic sensing portion 25 can be used as a bias magnetic field.

The magnitude of the bias magnetic field applied to the magneto-sensitive portion 25 in the element longitudinal direction is set to 400 (A / m) (5 (O
e)) or less, preferably 320 (A / m) (4 (O
e)) or less, more preferably 160 (A / m) (2O
e) If it is possible to reduce the number of turns, the number of turns of the coil wound around the magneto-sensitive portion 25 is reduced in order to apply a bias magnetic field to the magneto-sensitive portion 25. Will be able to Also,
The size reduction required when applying the magneto-impedance effect element M to a magnetic head or a weak magnetic field detector is also facilitated. Further, since the DC current applied to the coil for generating the bias magnetic field can be reduced, the power saving of the magneto-impedance effect element M can be facilitated.

As the ratio (aspect ratio) W / L of the element width W and the element length L of the magnetosensitive portion of the magneto-impedance effect element is reduced, the effect of improving the magnetic field detection sensitivity of the magneto-impedance effect element is improved. It is obtained for the following reasons.

Since the magnetic sensing portion is excited by a high frequency alternating current, a strong skin effect appears. At this time, the element width W, the element length L, the specific resistance ρ, the excitation frequency ω, the magnetic permeability μ in the element width direction, and the magnitude | Z | , (2).

[0149]

(Equation 2) From equation (2), when the element width W, element length L, specific resistance ρ, and excitation frequency ω of the magnetic sensing part are constant, the magnitude | Z | of the impedance of the magnetic sensing part is in the element width direction. Is proportional to the half of the magnetic permeability μ.

An alternating current is applied in the longitudinal direction of the element, and in the longitudinal direction of the element of the magnetosensitive portion which is excited in the width direction of the element,
When an external magnetic field is applied, the magnetic permeability μ of the magnetically sensitive part in the element width direction changes, and the magnitude | Z | of the impedance of the magnetically sensitive part changes. The external magnetic field applied to the magnetic sensing unit is detected by measuring a change in the magnitude | Z | of the impedance of the magnetic sensing unit.

As the aspect ratio W / L decreases, the rate of change of the magnitude | Z | of the impedance with respect to the change of the magnetic permeability μ in the element width direction increases. That is, the change in the magnitude of the output voltage drawn from both ends of the magneto-sensitive portion increases, and the magnetic field detection sensitivity of the magneto-impedance effect element improves.

FIG. 12 is a conceptual plan view showing an example of the magnetic domain structure of the soft magnetic thin film constituting the magnetic sensing part of the magneto-impedance effect element.

In FIG. 12, the soft magnetic thin film 2 forming the magnetic sensing part 25 of the magneto-impedance effect element M shown in FIG.
2 and 24, the magnetic domain structure of the soft magnetic thin film 22 is shown. The magnetic domain structure of the soft magnetic thin film 24 is almost the same as the magnetic domain structure of the soft magnetic thin film 22. The soft magnetic thin film 22 has a magnetic anisotropy in the element width direction by being formed in a static magnetic field or by using a soft magnetic material having strong anisotropy. Therefore, a magnetic domain 22a in which the magnetic moment is oriented in the element width direction is formed. The element width of the soft magnetic thin film 22 in FIG.

On the other hand, the soft magnetic thin film 2
A magnetic domain 22b in which the magnetic moment is oriented in the element longitudinal direction is formed.

When the aspect ratio of the soft magnetic thin film 22 is large, the total area of the magnetic domains 22b in which the magnetic moment is oriented in the element longitudinal direction is larger than the total area of the magnetic domains 22a in which the magnetic moment is oriented in the element width direction. , Remarkably narrow.

FIG. 13 shows a magneto-impedance effect element M
FIG. 8 is a conceptual plan view showing another magnetic domain structure of the soft magnetic thin film 22 of FIG.

For example, by setting the element width of the soft magnetic thin film 22 to W2 smaller than W1, the aspect ratio of the soft magnetic thin film 22 is made smaller than 0.1.

In FIG. 13, the magnetic domain 22b is a magnetic domain in which the component in the element longitudinal direction is larger when the component of the magnetic moment in the element longitudinal direction and the component in the element width direction are compared. The components in the element width direction are larger magnetic domains. In FIG. 13, the total area of the magnetic domains 22b is almost the same as the total area of the magnetic domains 22b in FIG.
The total area of the magnetic domains 22a is smaller than the total area of the magnetic domains 22a in FIG. 12, and the value of the total area of the magnetic domains 22a and 22b is equal. Then, the direction of the magnetic anisotropy as a whole of the soft magnetic thin film 22 becomes substantially isotropic.

When the total area of the magnetic domain 22b, which is a magnetic domain having a larger component in the element longitudinal direction, and the total area of the magnetic domain 22a, which is a magnetic domain having a larger component in the element width direction, antagonize. When the magnetic anisotropy energies in the element longitudinal direction are balanced, the soft magnetic thin film 22 has a state in which the direction of the magnetic anisotropy is substantially isotropic as a whole. That is, the magnetic moment of the soft magnetic thin film 22 is hard to be fixed in a certain direction, and the direction of the magnetic moment is easily changed when excited by an alternating current. That is, the magnetic permeability μ of the soft magnetic thin film 22 in the element width direction increases.

When the magnetic permeability μ of the soft magnetic thin film 22 in the element width direction takes the maximum value, the magnitude Z of the impedance of the soft magnetic thin film 22 becomes maximum, and the output voltage from both ends of the soft magnetic thin film 22 also becomes maximum. .

In FIG. 13, when the external magnetic field is not applied, the soft magnetic thin film 22 is in a state where the direction of the magnetic anisotropy is almost isotropic as a whole.

Accordingly, the direction of the magnetic anisotropy of the soft magnetic thin film 22 as a whole can be adjusted without applying the external magnetic field Hex or slightly applying the external magnetic field Hex in the element longitudinal direction of the soft magnetic thin film 22. Let it be almost isotropic,
The magnetic permeability μ in the element width direction of the soft magnetic thin film 22 can be maximized, and the output voltage Emi from both ends of the soft magnetic thin film 22 can be maximized.

That is, when an external magnetic field Hex is applied to the soft magnetic thin film 22 to which the driving AC current is applied, the absolute value Hp of the magnitude of the external magnetic field Hex that maximizes the output voltage Emi from the soft magnetic thin film 22 Can be reduced.

The soft magnetic thin film 22 may have a single magnetic domain structure, and the component of the magnetic moment in the element longitudinal direction and the component in the element width direction may be balanced in each magnetic domain.

In the magneto-impedance effect element of the present invention, as shown in FIG. 14, the total area of the magnetic domain 22b, which is a magnetic domain having a larger component in the element longitudinal direction, is larger than the component in the element width direction. Even when the total area of the magnetic domains 22a, which are large magnetic domains, is larger than the total area of the magnetic domains 22a, the direction of the magnetic anisotropy of the soft magnetic thin film 22 can be made to be almost isotropic as a whole. It is possible to obtain the same magnetic field detection sensitivity as that of the magneto-impedance effect element having the soft magnetic thin film 22 having the magnetic domain structure in which the total area of the magnetic field 22a is opposed to the total area.

Further, in the magneto-impedance effect element of the present embodiment, the magnetic field detection sensitivity is set to at least 0.3 (mV · m / A), which is a practical range as a magnetic field sensor.
(25 mV / Oe) or more.

Further, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magnetic sensing unit 25 can be reduced.

FIG. 15 to FIG. 17 are longitudinal sectional views of a magneto-impedance effect element according to an embodiment of the present invention, in which a bias magnetic field can be applied by a thin-film magnetic material.

The magneto-impedance effect element shown in FIG.
A magnetic sensing portion 94 including a soft magnetic thin film 91, a conductive thin film 92, and a soft magnetic thin film 93 is formed on the substrate 21, and electrodes 95, 95 are formed at both ends of the magnetic sensing portion 94 in the element longitudinal direction. Hard magnetic layers 96, 96, which are magnetic thin films, are provided in contact with both ends of the magnetic sensing portion 94. The hard magnetic layers 96 are formed of a hard magnetic material such as CoPt.

The magnitude of the bias magnetic field that can be given by the hard magnetic layers 96, 400 is 400 A / m at maximum.
However, in the magneto-impedance effect element of the present embodiment, the magnitude of the necessary bias magnetic field applied in the element longitudinal direction of the magneto-sensitive portion 94 can be 400 (A / m) or less. Hard magnetic layers 96 and 9 as shown in FIG.
6, a sufficient bias magnetic field can be applied to the magnetic sensing portion 94. In other words, there is no need to use a winding coil through which a DC current is applied to apply a bias magnetic field.
The size and power consumption of the magneto-impedance effect element can be reduced.

As shown in FIG. 16, hard magnetic layers 96, 96 are formed on both ends of the magnetosensitive portion 94 in the element longitudinal direction, and electrodes 95, 95 are formed on the hard magnetic layers 96, 96. May be formed.

Alternatively, as shown in FIG. 17, antiferromagnetic layers 97, 97 are laminated on the upper and lower layers of the magnetic sensing part 94, and the soft magnetic thin films 91, 93 of the magnetic sensing part 94 and the antiferromagnetic layer 9 are formed.
A necessary bias magnetic field can be applied to the magnetosensitive part 94 by an exchange anisotropic magnetic field generated at the interface with the magnetic heads 7 and 97.

FIGS. 18 and 19 are perspective views for explaining a method of manufacturing the magneto-impedance effect element of FIG.

FIG. 18 shows that a soft magnetic thin film 22, a conductive thin film 23 and a soft magnetic thin film 24 are sequentially formed on a substrate 21 made of a non-magnetic material such as alumina titanium carbide, glass, ceramic, crystallized glass by sputtering. FIG. 4 is a perspective view showing a state where films are formed by a method or a plating method and stacked.

[0175] The soft magnetic thin film 22 and 24, for example, the composition formula is represented by _{Fe 71.4 Al 5.8 Si 13.1 Hf 3} .3 C 4.5 Ru 1.9, microcrystalline soft magnetic alloy mainly composed of crystal grains of the bcc-Fe It is a thin film.

A TXMZQ system other than this composition (the element T is an element containing one or both of Fe and Co, and the element X is one of Si and Al Alternatively, it is an element containing both, and the element M is Ti, Z
r, Hf, V, Nb, Ta, Mo, W are one or more elements selected from the group consisting of C and N; C
one or more elements selected from the group consisting of r, Re, Ru, Rh, Ni, Pd, Pt, and Au), a microcrystalline soft magnetic alloy thin film, and a Co—T—M—X—O system (element T is , Fe, N
element containing one or both of i,
Element M is Ti, Zr, Hf, V, Nb, Ta, Cr,
One or more elements selected from Mo, Si, P, C, W, B, Al, Ga, Ge and rare earth elements;
X is Au, Ag, Cu, Ru, Rh, Os, Ir, P
one or two or more elements selected from t and Pd), bcc-Fe, bcc-FeCo, bcc
A microcrystalline soft magnetic alloy thin film comprising a crystalline phase composed of Co or the like and having an average crystal grain size of 10 to 30 nm and an amorphous phase containing an oxide of M, wherein the amorphous phase occupies 50% or more of the entire structure; Or Fe-MO system (M is Ti, Zr, Hf, V, N
one or two selected from b, Ta, W and a rare earth element
Element), a crystal phase mainly composed of bcc-Fe and having an average crystal grain size of 10 to 30 nm, and an amorphous phase containing M oxide. The soft magnetic thin films 22 and 24 may be formed as microcrystalline soft magnetic alloy thin films occupying 50% or more.

Alternatively, the soft magnetic thin films 22 and 24 may be formed as a Co—Ta—Hf based amorphous soft magnetic alloy thin film or a Co—Zr—Nb based amorphous soft magnetic alloy thin film.

The conductive thin film 23 is made of Cu, Ni, Ti, C
It is formed of a conductive material such as r. The material used to form the conductive thin film 23 is a soft magnetic thin film 2.
Any material may be used as long as it has a lower specific resistance than 2,24. For example, a ferromagnetic material containing Fe and Co or an antiferromagnetic material such as NiO and CoO may be used. However, the specific resistance of the material used for forming the conductive thin film 23 is preferably a material having a specific resistance of 1/10 or less of the specific resistance of the material used for forming the soft magnetic thin films 22 and 24.

In this embodiment, the soft magnetic thin film 2
2. The conductive thin film 23 and the soft magnetic thin film 24 are formed by RF
This was performed using a magnetron sputtering apparatus. The conditions at the time of film formation are in the following range.

High frequency power: 200 to 400 (W) Ar gas pressure: 50 (sccm) Film forming pressure: 3 to 7 (mTorr) Static magnetic field strength during film forming: 790 or more (A / m) Film forming speed: 10 The standard conditions are a high frequency power of 400 (W), an Ar gas pressure of 50 (sccm), and a film forming pressure of 7 (mTorr).
r), the static magnetic field strength during film formation is 4740 (A / m), and the film formation rate is 33.5 (nm / min). The substrate was cooled by indirect cooling.

Next, the soft magnetic thin film 22, the conductive thin film 23,
Then, the soft magnetic thin film 24 is patterned by photolithography and etching as shown in FIG. At this time, the ratio W / L (aspect ratio) of the element width W to the element length L is set to
A substantially rectangular pattern is formed so as to be 0.1 or less.

The magnetic sensing unit 25 has, for example, an element width W of 100
μm and the element length L is 6 mm. Therefore, the aspect ratio of the magneto-sensitive portion 25 of the magneto-impedance effect element M of the present embodiment is W / L = 0.017.

The magnetic sensing part 25 is formed over the entire surface of the substrate 21, but FIG. 6 shows only a part thereof.

In the present embodiment, after the magneto-sensitive portion 25 is patterned, a static magnetic field H2 is applied to the magneto-sensitive portion 25 in the element width direction and heat treatment is performed.

The soft magnetic thin film 22 and the soft magnetic thin film 24
When forming the film, a static magnetic field H1 may be applied in the direction of the arrow in FIG. 18 which becomes the element width direction when the magneto-impedance effect element of FIG. 1 is completed. When film formation is performed in a magnetic field as described above, the step of heat treatment in a static magnetic field after the film formation can be omitted. Alternatively, after film formation in a magnetic field, heat treatment in a rotating magnetic field or in a non-magnetic field may be performed instead of the heat treatment in a static magnetic field.

The conditions for the heat treatment in a static magnetic field, or in a rotating magnetic field or in a non-magnetic field are as follows.

Static magnetic field strength: 0 to 79000 (A / m) Heat treatment temperature: 540 to 675 (° C.) Heat treatment time: 20 to 30 (min) Heating rate: 10 to 14 (° C./min) , The static magnetic field strength is 79000 (A /
m), a heat treatment temperature of 575 (° C.), and a heat treatment time of 30
(Minutes) and the rate of temperature rise is 13.6 (° C./minute).

In this embodiment, the soft magnetic thin film 22, the conductive thin film 23, and the soft magnetic thin film 24 as shown in FIG.
Are sequentially formed, and as shown in FIG. 19, the magnetically sensitive portion 25 is patterned and then heat-treated in a static magnetic field.
Soft magnetic thin film 22, conductive thin film 23, and soft magnetic thin film 24
After the film formation, before the pattern formation of the magneto-sensitive portion 25, that is, in the state of FIG. 18, a heat treatment in a static magnetic field is performed.
The magnetic sensing portion 25 may be formed in a pattern.

The heat treatment in a static magnetic field, a rotating magnetic field, or a non-magnetic field causes the shape magnetic anisotropy of the soft magnetic thin film generated in the element longitudinal direction to substantially oppose the magnetic anisotropy in the element width direction. This is performed in order to make the direction of the magnetic anisotropy of the magnetic sensing portion as a whole substantially isotropic.

That is, the film formation in a magnetic field and the heat treatment step are performed to maintain the magnetic permeability μ in the element width direction high even when the aspect ratio W / L is reduced. This is not only for providing magnetic anisotropy in the element width direction.

After patterning the magnetically sensitive portion 25 and performing a heat treatment in a magnetic field, as shown in FIG. 1, an electrode made of a conductive material such as Cu, Ni, Ti, or Cr is provided on both ends of the magnetically sensitive portion 25. The portions 26 are formed by sputtering, photolithography, and etching.

After forming the electrode portions 26, 26, the substrate 21 is cut to obtain individual magneto-impedance effect elements M as shown in FIG.

When manufacturing a magneto-impedance effect element as shown in FIG. 2, a soft magnetic thin film 32 and a conductive thin film 33 are formed on the substrate 21 by patterning.
Is formed so that the soft magnetic thin film 32 and the soft magnetic thin film 34 are magnetically connected at both ends in the element width direction.

When manufacturing a magneto-impedance effect element as shown in FIG. 3, a soft magnetic thin film 42, a conductive thin film 43 and a soft magnetic thin film 43 are formed on a substrate 21 made of a non-magnetic material such as alumina titanium carbide, glass, ceramic, crystallized glass and the like. The soft magnetic thin film 44 is sequentially formed by a sputtering method, an evaporation method, a plating method, or the like to form a multilayer film similar to that shown in FIG. 18, and then a photoresist is laminated on the soft magnetic thin film 44. The photoresist is formed in the same shape and the same size as the magnetic sensing part 45 to be formed. For example, a width of 100 μm,
It is formed in a substantially rectangular shape with a length of 6 mm.

Next, the magneto-sensitive portion 45 is patterned by etching the multilayer film on which the photoresist is laminated using an acidic aqueous solution containing hydrofluoric acid, aqueous hydrogen peroxide, or the like. As a result of the etching process, the dimension of the element in the element width direction (X direction) gradually decreases as the magnetic sensing part 45 moves away from the surface of the substrate 21, that is, FIG.
The tapered surfaces 45c and 45 at both ends in the element width direction as shown in FIG.
c can be formed.

When manufacturing the magneto-impedance effect element shown in FIGS. 7 and 8, after forming a soft magnetic thin film 81 on the substrate 21, the insulating layer 82, the conductive thin film 83, and the insulating layer 84 are formed. The conductive thin film 83 is sequentially laminated.
It is sufficient to form the electrode portions 87, 87 that are electrically connected to only the electrodes.

In FIG. 19, the magneto-sensitive portion 25 of the magneto-impedance effect element has a structure in which the soft magnetic thin film 22 and the soft magnetic thin film 24 are laminated on the upper and lower sides of the conductive thin film 23. The step of further laminating a conductive thin film and a soft magnetic thin film on top may be repeated.

When manufacturing the magneto-impedance effect element shown in FIGS.
After forming 5,55,67,74,86, the magnetic sensing part 3
A static magnetic field is applied in the element width direction of 5, 45, 55, 67, 74, 86.

The magnetic sensing units 35, 45, 55, 67, 7
When forming the soft magnetic thin film included in the magnetic heads 4 and 86, a static magnetic field may be applied in a direction corresponding to the element width direction of the magneto-sensitive portion. When film formation is performed in a magnetic field as described above, the step of heat treatment in a static magnetic field after the film formation can be omitted. Alternatively, after film formation in a magnetic field, heat treatment in a rotating magnetic field or in a non-magnetic field may be performed instead of the heat treatment in a static magnetic field.

The magnetic sensing units 25, 35, 45, 55, 6
7, 74, 86 may be formed in a U-shaped or serpentine pattern. Magnetic sensing part 25, 35, 45, 55, 6
In the case where the 7, 74 and 86 are formed in a U-shape or a broken shape, the magnetic sensing portions 25, 35, 45, 55, 67, 74, and
The sum of the lengths of the portions 86 facing the element longitudinal direction is the element length L. Magnetic sensing part 25, 35, 45, 55, 67, 7
When 4, 86 is formed in a U-shape or a broken shape, the magnetic sensing portions 25, 35, 45, 55, 67, 74, 8 are formed.
The extension direction of the longest straight line portion in 6 is the element longitudinal direction, and this direction coincides with the direction perpendicular to the excitation direction of the magnetic field generated by the driving AC current.

Magnetic sensing units 25, 35, 45, 55, 67, 7
4, 86 are formed, for example, with an element width W of 0.10 mm and an element length L of 6 mm. At this time, the magnetic sensing units 25, 35, 45, 55, 6 of the magneto-impedance effect element
The aspect ratio of 7, 74, 86 is W / L = 0.017.
It is.

At this time, after the formation of the magneto-impedance effect element, the magnetic sensing portions 25, 35, 45, 55, 67, 74,
When an external magnetic field is applied while a drive AC current is applied in the longitudinal direction of the element 86, the magnetic sensing units 25, 35, 45, 55,
The absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of 67, 74, and 86 is 400 (A / m) or less.

Magnetic sensing parts 25, 35, 45, 55, 67, 7
By forming the film 4,86 in a static magnetic field, the shape of the soft magnetic thin film included in the magneto-sensitive portions 25,35,45,55,67,74,86 in the element longitudinal direction (X direction). The magnetic anisotropy energy and the magnetic anisotropy energy in the element width direction (Y direction) can be substantially balanced. That is, as shown in FIG. 13, the total area of the magnetic domains 22b whose components in the element longitudinal direction are larger is equal to the total area of the magnetic domains 22a whose magnetic components in the element width direction are larger. 14, or as shown in FIG. 14, the total area of the magnetic domains 22b whose components in the element longitudinal direction are larger is larger than that of the magnetic domains 22a whose components in the element width direction are larger. Those having a magnetic domain structure larger than the total area can be obtained.

FIG. 20 is a configuration diagram showing the internal structure of the RF magnetron sputtering apparatus used in the present embodiment.

As shown in FIG. 20, in a chamber 102 of a magnetron sputtering apparatus 101, an electrode section 105 for attaching targets 103 and 104 is provided.
A substrate holding unit 106 is provided at a position facing the targets 103 and 104. The substrate 21 is placed on the substrate holding unit 106.

The target 103 is made of a soft magnetic material, and the target 104 is made of a conductive material. Further, a shielding plate 107 is provided between the target 103 and the target 104.

A discharge magnet (not shown) is provided in the electrode portion 105, and an erosion region (not shown) is formed on the surfaces of the targets 103 and 104 by a magnetic field generated from the discharge magnet. It is formed.

The chamber 102 is provided with a gas inlet 108 and a gas outlet 109, through which Ar (argon) gas is introduced.

A high frequency power supply (RF power supply) is
When a high frequency is applied from 110, a magnetron discharge is generated due to the interaction between an electric field and a magnetic field, and the targets 103 and 104 are sputtered.

When the substrate 21 on which the thin film is laminated is located in the region A below the target 103 made of a soft magnetic material,
When the soft magnetic thin film is formed and is in the region B below the target 104 made of a conductive material, the conductive thin film is formed.

First, the target 10 made of a soft magnetic material is used.
The substrate 21 is arranged in the area A below the area 3. Substrate holder 10
6 is rotating in the direction of the arrow. As the substrate holder 106 rotates, the substrate 21 moves to the region B below the target 104 made of a non-magnetic material while the soft magnetic thin film 22 is formed on the substrate 21, and the conductive film is placed on the soft magnetic thin film 22. The conductive thin film 23 is formed. The substrate holding unit 106 continues to rotate further, and the substrate 21 moves again to the area A below the target 103, and the soft magnetic thin film 24 is formed on the conductive thin film 23, and the state shown in FIG.

Further, by continuing to operate the RF magnetron sputtering apparatus and continuing to rotate the substrate holding unit 106, an arbitrary number of conductive thin films and soft magnetic thin films can be laminated.

When performing film formation in a magnetic field, a magnet for applying a static magnetic field to the soft magnetic thin film being formed is provided with the substrate holding portion 106 interposed therebetween. The magnet is, for example, S
It is formed of a hard magnetic material such as m-Co or an electromagnet.

[0214] As the sputtering apparatus, in addition to the RF magnetron sputtering apparatus 101 shown in FIG.
An existing device such as an RF bipolar sputtering device, an RF tripolar sputtering device, an ion beam sputtering device, or a facing target type sputtering device may be arbitrarily used.

In addition, the method for forming the soft magnetic thin film and the conductive thin film according to the present invention includes, besides the sputtering method, the vapor deposition method and the MBE method.
(Molecular-beam-epitaxy) method, ICB
(Ion-cluster-beam) method or plating method may be used.

When the magnetic sensing portion 25 is formed using a soft magnetic ribbon, for example, a liquid quenching device C shown in FIG. 21 is used.

First, a Fe—Co—Si—B-based soft magnetic material is charged into a nozzle 111 made of quartz.
11 is heated by a heater 112 provided around
Is melted. A cooling roll 114 rotating the molten alloy 113 at a high speed by the pressure applied from the upper part of the nozzle
The soft magnetic ribbon 1
15 are formed.

The obtained soft magnetic ribbon 115 is cut into a substantially rectangular shape so that the ratio (aspect ratio) W / L of the element width W to the element length L is 0.1 or less. This soft magnetic ribbon 11
5, a sputtered conductive thin film on at least one surface of
It is formed by a method such as vapor deposition.

Next, at least two or more soft magnetic ribbons in which the conductive thin films are sequentially laminated on a substrate to form a magnetically sensitive portion are formed, and then the magnetically sensitive portion is exposed to a static magnetic field in the element width direction. Heat treatment.

Further, when electrode portions are formed at both ends of the magnetically sensitive portion, a magneto-impedance effect element as shown in FIG. 1 is obtained.

FIGS. 22 to 25 are schematic views of the soft magnetic thin film 24 of the magneto-sensitive section 25 of the magneto-impedance effect element shown in FIG. 1 observed and photographed with a Kerr effect polarizing microscope.

FIG. 22 shows that the magnetic sensing part 25 is moved in the longitudinal direction of the element (X
Direction) L = 2 mm, element width direction (Y direction) length W = 100 μm, that is, aspect ratio W / L = 0.0
The magnetic domain structure of the soft magnetic thin film 24 formed as No. 5 is shown. FIGS. 23 and 24 show that the magnetosensitive part 25 has a length L = 4 mm in the element longitudinal direction and a dimension W = 100 in the element width direction.
3 shows the magnetic domain structure of the soft magnetic thin film 24 formed with μm, that is, the aspect ratio W / L = 0.025.

FIGS. 22 and 23 show a state in which the total area of magnetic domains in which the magnetic moment is oriented in the element width direction and the total area of the magnetic domains in which the magnetic moment is oriented in the element longitudinal direction are in opposition. As a result, the magnetic anisotropy energy in the element width direction and the element longitudinal direction are balanced, and the direction of the magnetic anisotropy is substantially isotropic as a whole.

In FIG. 24, the total area of magnetic domains in which the magnetic moment is oriented in the element longitudinal direction is larger than the total area of the magnetic domains in which the magnetic moment is oriented in the element width direction. However, the magnetic anisotropy energy in the element width direction and the element longitudinal direction are balanced, and the direction of the magnetic anisotropy is substantially isotropic as a whole.

That is, in any of the soft magnetic thin films 24 shown in FIGS. 22 to 24, the magnetic moment is hard to be fixed in a certain direction, and the direction of the magnetic moment is easily changed when excited by an alternating current. Has become. That is, the magnetic permeability μ of the magneto-sensitive portion 25 in the element width direction increases, and the magnetic field detection sensitivity of the magneto-impedance effect element increases. Further, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magnetic sensing unit 25 can be reduced, and the required magnitude of the bias magnetic field can be reduced.

FIG. 25 shows that the magnetosensitive portion has a length L = 4 mm in the element longitudinal direction (X direction) and a length W in the element width direction (Y direction).
= 500 μm, that is, the aspect ratio W / L = 0.12
5 shows the magnetic domain structure of the soft magnetic thin film 24 formed as No. 5.

In FIG. 25, the magnetic domains in which the magnetic moment is oriented in the element width direction occupy a large part, and the direction of the magnetic anisotropy is oriented in the element width direction.

That is, the magnetic permeability μ of the magnetosensitive portion in the element width direction.
Is small, and the magnetic field detection sensitivity of the magneto-impedance effect element is small. Further, the absolute value of the magnitude of the external magnetic field that maximizes the output voltage from both ends of the magnetic sensing unit is large, and the required bias magnetic field is also large.

Each of the magneto-sensitive portions shown in FIGS. 22 to 25 has a FeAlSiHfCRu-based composition and has a bcc-
It is formed of a microcrystalline soft magnetic alloy thin film mainly composed of Fe crystal grains, and the thickness of the magneto-sensitive portion is 4 μm.

FIGS. 22 to 25 show the magnetic domain structure of the uppermost soft magnetic thin film 24 of the magneto-sensitive portion 25 of the magneto-impedance effect element of FIG.
2 also showed a similar magnetic domain structure.

[0231]

FIG. 26 and FIG. 27 are graphs showing the results of measuring the magneto-impedance effect characteristics using the magneto-impedance effect element shown in FIG.

In a state where a driving alternating current is applied from the electrodes 26 of the magneto-impedance effect element M to both ends of the magneto-sensitive section 25 in FIG. Apply. The output voltage Emi is changed while changing the magnitude of the applied external magnetic field Hex.
Was measured.

FIG. 26 shows that the magnetic sensing part is made of FeAlSiHfCR.
It has a u-type composition, is formed of a microcrystalline soft magnetic alloy thin film mainly composed of bcc-Fe crystal grains, the length of the magnetosensitive portion 25 in the element longitudinal direction is 4 mm, the thickness is 4 μm, and the element width is This is the result when the direction dimension is changed.

Referring to FIG. 26, the dimensions of the magnetosensitive portion 25 in the element width direction are 1000 μm (W / L = 0.25) and 500 μm.
When m (W / L = 0.125), the output voltage hardly changes when the magnitude of the external magnetic field is changed, indicating that the sensor does not function as a magnetic field sensor. The absolute value of the magnitude of the external magnetic field that maximizes the output voltage exceeds 400 (A / m).

On the other hand, when the dimension of the magneto-sensitive portion 25 in the element width direction is 10
0 μm (W / L = 0.025), when the magnitude of the external magnetic field is changed, the change in the output voltage is up to 20 μm.
0 mV or more, which indicates that it functions as a highly sensitive magnetic field sensor. The absolute value of the magnitude of the external magnetic field that maximizes the output voltage is 160 (A / m).

The dimension of the magneto-sensitive portion 25 in the element width direction is 10
When the thickness is 0 μm (W / L = 0.025), the soft magnetic thin film forming the magnetic sensing part 25 has a single magnetic domain structure or a multi-domain structure. When the components in the width direction are compared, the total area of the magnetic domains in which the component in the element longitudinal direction is larger is equal to the total area of the magnetic domains in which the component in the element width direction is larger, or The total area of the magnetic domain having a larger component in the element longitudinal direction is larger than the total area of the magnetic domain having a larger component in the element width direction.

FIG. 27 shows that the magnetic sensing part 25 is made of FeAlSiHf.
The magnetic sensing portion 25 is formed of a microcrystalline soft magnetic alloy thin film having a CRu-based composition and mainly composed of bcc-Fe crystal grains.
Are the results when the length in the element longitudinal direction is 6 mm, the thickness is 4 μm, and the dimension in the element width direction is changed.

Referring to FIG. 27, when the size of the magnetosensitive portion 25 in the element width direction is 1000 μm (W / L = 0.17), the change in the output voltage hardly occurs when the magnitude of the external magnetic field is changed. It can be seen that it did not function as a magnetic field sensor. The absolute value of the magnitude of the external magnetic field that maximizes the output voltage exceeds 400 (A / m).

On the other hand, when the dimension of the magnetosensitive portion 25 in the element width direction is 50,
At 0 μm (W / L = 0.08), when the magnitude of the external magnetic field is changed, the change in the output voltage is 50 m at the maximum.
V or more, which indicates that it can function as a magnetic field sensor. The absolute value of the magnitude of the external magnetic field that maximizes the output voltage is 320 (A / m). Furthermore, the magnetic sensing part 2
5 is 100 μm (W / L = 0.01)
In the case of 7), when the magnitude of the external magnetic field is changed, the change of the output voltage is 600 mV or more at the maximum, and it can be seen that the sensor can function as a very sensitive magnetic field sensor. The absolute value of the magnitude of the external magnetic field that maximizes the output voltage is 0 to 24 (A / m).

The size of the magneto-sensitive portion 25 in the element width direction is 50.
When the thickness is 0 μm or 100 μm, the soft magnetic thin film constituting the magnetic sensing part 25 has a single domain structure or a multi-domain structure, and compares the component of the magnetic moment in the element longitudinal direction and the component in the element width direction in each magnetic domain. Then, the total area of the magnetic domains whose component in the element longitudinal direction is larger and the total area of the magnetic domains whose component in the element width direction is larger, or the component of the element longitudinal direction is larger. The total area of the larger magnetic domains is larger than the total area of the larger magnetic domains in the element width direction.

FIG. 28 shows the aspect ratio of the magneto-sensitive section 25 and the external ratio using a magneto-impedance effect element in which the length of the magneto-sensitive section 25 in the element longitudinal direction is fixed to 3 mm and the dimension in the element width direction is variously changed. 9 is a graph showing the result of examining the relationship between the output voltage and the amount of change when a magnetic field is applied.

The amount of change in the output voltage shown in FIG.
This is a voltage change amount when the external magnetic field is changed by 320 (A / m).

When the magneto-impedance effect element is used as a magnetic field sensor, it is preferable that the output change amount in the graph of FIG. 28 be 100 mV or more. Therefore, it is understood that it is preferable to set the aspect ratio (W / L) of the magnetically sensitive portion to 0.004 or more.

In FIG. 28, the aspect ratio of the magneto-sensitive portion when the output change amount takes the maximum value is 0.017.

[0245]

According to the present invention described in detail above,
Since the magnetically sensitive portion of the magneto-impedance effect element has a structure in which the soft magnetic portion and a conductive portion having a lower specific resistance than the soft magnetic portion are in contact with each other, a drive AC is applied to the magnetically sensitive portion. When a current is applied, the driving AC current flows separately into a current flowing in the soft magnetic body portion and a current flowing in the soft magnetic body portion, and the drive AC current flows through the magnetic sensing portion when the driving AC current flows. The DC resistance value is reduced, and the power consumption of the magneto-impedance effect element can be reduced.

According to the present invention, since the magnetically sensitive portion has a structure in which a soft magnetic material portion having a high magnetic permeability and a conductive material portion having a high electrical conductivity are in contact with each other, the driving force flowing through the magnetically sensitive portion is provided. The skin thickness of the alternating current is reduced, and a large magneto-impedance effect can be generated. Therefore, a sufficient amount of change in the output voltage with respect to the magnetic field can be obtained even at a low drive voltage.

[Brief description of the drawings]

FIG. 1 is a perspective view of a magneto-impedance effect element according to a first embodiment of the present invention,

FIG. 2 is a sectional view of a magneto-impedance effect element according to a second embodiment of the present invention;

FIG. 3 is a sectional view of a magneto-impedance effect element according to a third embodiment of the present invention;

FIG. 4 is a sectional view of a magneto-impedance effect element according to a fourth embodiment of the present invention;

FIG. 5 is a sectional view of a magneto-impedance effect element according to a fifth embodiment of the present invention;

FIG. 6 is a sectional view of a magneto-impedance effect element according to a sixth embodiment of the present invention;

FIG. 7 is a perspective view of a magneto-impedance effect element showing a seventh embodiment of the present invention;

FIG. 8 is a sectional view of a magneto-impedance effect element according to a seventh embodiment of the present invention;

FIG. 9 is a graph showing a relationship between an aspect ratio of a magnetic sensing part of the magneto-impedance effect element and a magnetic field detection sensitivity.

FIG. 10 is a graph showing the relationship between the aspect ratio of the magneto-sensitive portion of the magneto-impedance effect element and the absolute value Hp of the magnitude of the external magnetic field that maximizes the output voltage Emi from both ends of the magneto-sensitive portion;

FIG. 11 is a conceptual diagram showing a magneto-impedance effect characteristic of the magneto-impedance effect element of the present embodiment,

FIG. 12 is a conceptual plan view showing a magnetic domain structure of a magnetic sensing part of the magneto-impedance effect element.

FIG. 13 is a conceptual plan view showing a magnetic domain structure of a magnetic sensing part of the magneto-impedance effect element.

FIG. 14 is a conceptual plan view showing a magnetic domain structure of a magnetic sensing portion of the magneto-impedance effect element,

FIG. 15 is a cross-sectional view showing, as an embodiment of the magneto-impedance effect element of the present invention, a magneto-impedance effect element provided with a hard magnetic layer for applying a bias magnetic field;

FIG. 16 is a cross-sectional view showing a magneto-impedance effect element provided with a hard magnetic layer for applying a bias magnetic field as an embodiment of the magneto-impedance effect element of the present invention;

FIG. 17 is a cross-sectional view showing a magneto-impedance effect element provided with an antiferromagnetic layer for applying a bias magnetic field as an embodiment of the magneto-impedance effect element of the present invention;

FIG. 18 is a perspective view showing a state in which a soft magnetic thin film and a conductive thin film serving as a magnetic sensing portion are formed on a substrate made of a nonmagnetic material such as alumina titanium carbide;

FIG. 19 is a perspective view showing a state in which a magneto-sensitive portion is formed by patterning the multilayer film of FIG. 18 by photolithography and etching;

FIG. 20 is a cross-sectional view of an RF magnetron sputtering apparatus that can be used for carrying out the method for manufacturing a magneto-impedance effect element of the present invention.

FIG. 21 is a perspective view showing a liquid quenching device for forming a soft magnetic ribbon.

FIG. 22 is a schematic diagram of a magneto-sensitive part of the magneto-impedance effect element of the present invention observed and photographed by a Kerr effect polarizing microscope,

FIG. 23 is a schematic view of a magneto-sensitive part of the magneto-impedance effect element of the present invention, which is obtained by observing and photographing a magnetic sensitive part by a Kerr effect polarizing microscope;

FIG. 24 is a schematic diagram of a magneto-sensitive part of the magneto-impedance effect element according to the present invention, which is obtained by observing and photographing a magnetic sensitive part with a Kerr effect polarizing microscope;

FIG. 25 is a schematic view of a magneto-sensitive part of the magneto-impedance effect element according to the present invention, which is obtained by observing and photographing a magnetic sensitive part with a Kerr effect polarizing microscope;

FIG. 26 is a graph showing measured values of the magneto-impedance effect characteristics of the magneto-impedance effect element of the present invention;

FIG. 27 is a graph showing actually measured values of the magneto-impedance effect characteristics of the magneto-impedance effect element of the present invention;

FIG. 28 is a graph showing a relationship between an aspect ratio of a magneto-sensitive part of the magneto-impedance effect element and an output change amount;

FIG. 29 is a perspective view showing a conventional magneto-impedance effect element,

FIG. 30 is a circuit diagram showing a method of applying a driving alternating current to the magneto-impedance effect element and applying an external magnetic field;

[Explanation of symbols]

21 Substrate 22, 24, 32, 34, 42, 44, 52, 54, 6
2, 64, 66, 72, 81, 85 Soft magnetic thin film 23, 33, 43, 53, 63, 65, 73, 83 Conductive thin film 25, 35, 45, 55, 67, 74, 86 Magnetic sensing part 26, 87 electrode

Claims (39)

[Claims] 1. A magneto-impedance effect element comprising a substrate made of a non-magnetic material and a magneto-sensitive section having a magneto-impedance effect and an electrode section for supplying a drive alternating current to the magneto-sensitive section. The portion has a soft magnetic portion formed of a soft magnetic material, a conductor portion having a lower specific resistance than the soft magnetic portion, the soft magnetic portion and the conductor portion at least partially A magneto-impedance effect element characterized by being in contact with a magnetic field. 2. The magneto-impedance effect element according to claim 1, wherein said soft magnetic portion and said conductor portion are alternately laminated. 3. An uppermost layer and a lowermost layer are the soft magnetic portions, and the uppermost layer and the lowermost soft magnetic portions are magnetically coupled at least at ends in a device width direction. 3. The magneto-impedance effect element according to 2. 4. The magneto-impedance effect element according to claim 1, wherein an element width dimension on an upper surface of said magnetic sensing part is shorter than a dimension in an element width direction on a bottom surface of said magnetic sensing part. 5. The device according to claim 4, wherein the size of the magneto-sensitive portion gradually decreases as the distance from the surface of the substrate increases.
The magneto-impedance effect element as described in the above. 6. The magnetic device according to claim 1, wherein the soft magnetic body portion and the conductor portion are electrically insulated by an insulating layer, and the driving AC current flows only through the conductor portion. Impedance effect element. 7. A magnitude of the external magnetic field which maximizes an output voltage from both ends of the magnetically sensitive part when an external magnetic field is applied in the element longitudinal direction of the magnetically sensitive part to which a driving AC current is applied. Is not more than 400 (A / m).
7. The magneto-impedance effect element according to any one of items 6 to 6. 8. The absolute value of the magnitude of the external magnetic field which maximizes the output voltage from both ends of the magnetic sensing unit is 320 (A / A).
m) The magneto-impedance effect element according to claim 7, wherein 9. The absolute value of the magnitude of the external magnetic field which maximizes the output voltage from both ends of the magnetic sensing part is 160 (A / A).
m) The magneto-impedance effect element according to claim 7, wherein 10. The magneto-impedance effect element according to claim 1, wherein a ratio (aspect ratio) W / L of an element width W to an element length L of the magneto-sensitive portion is 0.1 or less. . 11. The magneto-impedance effect element according to claim 10, wherein a ratio (aspect ratio) W / L of an element width W to an element length L of the magneto-sensitive portion is 0.05 or less. 12. The magneto-impedance effect element according to claim 10, wherein a ratio (aspect ratio) W / L of an element width W to an element length L of the magneto-sensitive portion is 0.03 or less. 13. The soft magnetic body portion has a single magnetic domain structure or a multi-domain structure. When a component of a magnetic moment in a device longitudinal direction and a component in a device width direction are compared in each magnetic domain, the soft magnetic body portion has a structure in the element longitudinal direction. 13. The magneto-impedance effect element according to claim 1, wherein the total area of the magnetic domain having a larger component is equal to the total area of the magnetic domain having a larger component in the element width direction. 14. The soft magnetic body portion has a single magnetic domain structure or a multi-domain structure, and when the component of the magnetic moment in the element longitudinal direction is compared with the component of the magnetic moment in the element width direction in each magnetic domain, 13. The magneto-impedance effect element according to claim 1, wherein the total area of the magnetic domain having a larger component is larger than the total area of the magnetic domain having a larger component in the element width direction. 15. The magneto-impedance effect element according to claim 1, further comprising a magnetic body for applying a bias magnetic field in a direction parallel to a longitudinal direction of the element of the magneto-sensitive portion. 16. The soft magnetic part has a composition formula of Fe _h M _i.
The magneto-impedance effect element according to any one of claims 1 to 15, wherein the magneto-impedance effect element is represented by O _j and is a microcrystalline soft magnetic alloy thin film mainly composed of an amorphous structure. Where M is T
i, Zr, Hf, V, Nb, Ta, W and one or more elements selected from rare earth elements, and h, i,
j is at%, 45 ≦ h ≦ 70, 5 ≦ i ≦ 30, 10 ≦
j ≦ 40 and h + i + j = 100 are satisfied. 17. The soft magnetic material part has a composition formula (Co)
_{1-c T c) x M} y X z O claims 1 microcrystalline soft magnetic alloy thin film represented by _w 15 magneto-impedance effect element according to any one of. Here, the element T is an element containing one or both of Fe and Ni, and the element M
Are Ti, Zr, Hf, V, Nb, Ta, Cr, Mo,
X is one or more elements selected from Si, P, C, W, B, Al, Ga, Ge and rare earth elements;
Au, Ag, Cu, Ru, Rh, Os, Ir, Pt, P
d is one or more elements selected from the group consisting of: c is 0 ≦ c ≦ 0.7, x, y, z and w are at
%, 3 ≦ y ≦ 30, 0 ≦ z ≦ 20, 7 ≦ w ≦ 40, 2
The relationship of 0 ≦ y + z + w ≦ 60 is satisfied, and the balance is x. 18. The soft magnetic material part has a composition formula of T
Expressed in _{100-defg X d M e Z} f Q g, bcc-Fe, b
The magneto-impedance effect element according to any one of claims 1 to 15, wherein the magneto-impedance effect element is a microcrystalline soft magnetic alloy thin film mainly composed of one or more crystal grains of cc-FeCo and bcc-Co. Here, the element T is an element containing one or both of Fe and Co, and the element X is Si,
Al is an element containing one or both of Al, and the element M is Ti, Zr, Hf, V, Nb, Ta, M
one or more elements selected from o and W;
The element Z is an element containing one or both of C and N, and Q is Cr, Re, Ru, Rh, Ni,
At least one element selected from Pd, Pt, and Au, where d, e, f, and g are at%, and 0 ≦ d ≦ 25;
1 ≦ e ≦ 10, 0.5 ≦ f ≦ 15, and 0 ≦ g ≦ 10. 19. The soft magnetic part has a composition formula of T
Expressed in _{100-pqefg Si p Al q M} e Z f Q g, bcc-
One or two of Fe, bcc-FeCo, and bcc-Co
The magneto-impedance effect element according to any one of claims 1 to 15, wherein the magneto-impedance effect element is a microcrystalline soft magnetic alloy thin film mainly composed of at least one kind of crystal grains. Here, the element T is an element containing one or both of Fe and Co, and the element M
Is one or more elements selected from Ti, Zr, Hf, V, Nb, Ta, Mo, W, and the element Z is
C is an element containing one or both of C and N, and Q is Cr, Re, Ru, Rh, Ni, Pd, P
at least one element selected from t and Au, where p, q, e, f, and g are at% and 8 ≦ p ≦ 15, 0
≦ q ≦ 10, 1 ≦ e ≦ 10, 0.5 ≦ f ≦ 15, 0 ≦ g
It satisfies the relationship of ≦ 10. 20. The soft magnetic body part, wherein the composition formula is (Fe
_{1-a Co a) 100-} xy (Si 1-b B b) claims 1 an amorphous soft magnetic alloy thin film or ribbon represented by _x M _y 15
The magneto-impedance effect element according to any one of the above. Here, M is an element containing one or both of Cr and Ru, and a and b representing the composition ratio are 0.05 ≦ a
≦ 0.1, 0.2 ≦ b ≦ 0.8, and x and y are at%
Satisfy the relationship of 10 ≦ x ≦ 35 and 0 ≦ y ≦ 7. 21. The soft magnetic part, a composition formula Co _l T
a _m is represented by Hf _n, magneto-impedance effect element according to any one of claims 1 to 15 is an amorphous soft magnetic alloy thin film mainly the amorphous structure. Where l,
m and n are at%, 70 ≦ l ≦ 90, 5 ≦ m ≦ 21,
It satisfies the relationship of 6.6 ≦ n ≦ 15 and 1 ≦ m / n ≦ 2.5. 22. The soft magnetic material part has a composition formula of Co _a Z
magneto-impedance effect element according to any one of claims 1 to 15 an amorphous structure represented by r _b Nb _c is an amorphous soft magnetic alloy thin film mainly. Where a,
b and c are at%, 78 ≦ a ≦ 91, 0.5 ≦ b / c ≦
This satisfies the relationship of 0.8. 23. (a) On a substrate made of a non-magnetic material,
A step of alternately forming a soft magnetic thin film and a conductive thin film having a lower specific resistance than the soft magnetic thin film; and (b) a step of patterning a magnetically sensitive portion from the multilayer film formed in the step (a). (C) heat-treating the magneto-sensitive section in a static magnetic field in the element width direction of the magneto-sensitive section. 24. (d) On a substrate made of a non-magnetic material,
Alternately forming a soft magnetic thin film and a conductive thin film having a lower specific resistance than the soft magnetic thin film; and (e) forming the multilayer film formed by the step (d),
Heat-treating in a static magnetic field; and (f) forming a magnetosensitive portion by patterning the multilayer film so that the direction of the static magnetic field is the element width direction.
A method for manufacturing a magneto-impedance effect element, comprising: 25. In the step (a) or (d), the soft magnetic thin film is formed in a static magnetic field in the same direction as the static magnetic field in the step (c) or (e). 25. The method for manufacturing a magneto-impedance effect element according to 23 or 24. 26. An uppermost layer and a lowermost layer of the multilayer film are the soft magnetic thin films, and the uppermost soft magnetic thin film and the lowermost soft magnetic thin film are magnetically bonded at least at an end in the element width direction. The method for manufacturing a magneto-impedance effect element according to any one of claims 23 to 25, wherein the element is coupled. 27. When patterning the multilayer film,
24. A magneto-sensitive portion in which the dimension in the element width direction on the top surface is shorter than the dimension in the element width direction on the bottom surface is formed by laminating a photoresist on the upper layer of the multilayer film and etching the multilayer film by wet etching. 27. The method of manufacturing a magneto-impedance effect element according to any one of items 26. 28. The method according to claim 28, wherein forming the multilayer film includes forming an insulating layer between the soft magnetic thin film and the conductive thin film, and forming an electrode portion connected only to the conductive thin film. Item 28. The method for manufacturing a magneto-impedance effect element according to any one of Items 23 to 27. 29. The soft magnetic thin film having a composition formula of Fe _h M _i
The method for manufacturing a magneto-impedance effect element according to any one of claims 23 to 28, wherein the method is formed as a microcrystalline soft magnetic alloy thin film represented by O _j and mainly composed of an amorphous structure. Here, M is Ti, Zr, Hf, V, Nb, T
a, W and one or more elements selected from rare earth elements, and h, i and j are at% and 45 ≦ h ≦ 7
0, 5 ≦ i ≦ 30, 10 ≦ j ≦ 40, h + i + j = 10
0 is satisfied. 30. The soft magnetic thin film having the composition formula (Co)
_{1-c T c) x M} y X z O method for manufacturing a magneto-impedance effect element according to any one of claims 23 to 28, formed as a microcrystalline soft magnetic alloy thin film represented by _w. Here, the element T is an element containing one or both of Fe and Ni, and the element M is Ti, Zr, Hf, V, N
b, Ta, Cr, Mo, Si, P, C, W, B, Al,
X is one or more elements selected from Ga, Ge and rare earth elements, and X is Au, Ag, Cu, Ru, R
h, Os, Ir, Pt, Pd, and at least one element selected from the group consisting of: 0 ≦ c ≦ 0.
7, x, y, z, w are at%, 3 ≦ y ≦ 30, 0 ≦ z
≦ 20, 7 ≦ w ≦ 40, 20 ≦ y + z + w ≦ 60, and the balance is x. 31. A soft magnetic thin film having a composition formula of T
Expressed in _{100-defg X d M e Z} f Q g, bcc-Fe, b
29. The method for manufacturing a magneto-impedance effect element according to claim 23, wherein the thin film is formed as a microcrystalline soft magnetic alloy thin film mainly composed of one or more crystal grains of cc-FeCo and bcc-Co. Where the element T is F
e, an element containing one or both of Co, the element X is an element containing one or both of Si and Al, and the element M is Ti, Zr, H
f, V, Nb, Ta, Mo, W, or at least one element selected from the group consisting of C and N, and Q is Cr, R
e, Ru, Rh, Ni, Pd, Pt, Au is one or more elements selected from the group consisting of d, e, f, and g
At t%, 0 ≦ d ≦ 25, 1 ≦ e ≦ 10, 0.5 ≦ f ≦ 1
5, 0 ≦ g ≦ 10. 32. The soft magnetic thin film having the composition formula T
It expressed in _{100-pqefg Si p Al q M} e Z f Q g, bcc-
One or two of Fe, bcc-FeCo, and bcc-Co
29. The method for manufacturing a magneto-impedance effect element according to claim 23, wherein the thin film is formed as a microcrystalline soft magnetic alloy thin film mainly composed of at least one kind of crystal grains. However, the element T
Is an element containing one or both of Fe and Co, and the element M is Ti, Zr, Hf, V, Nb,
One or more elements selected from Ta, Mo, W; the element Z is an element containing one or both of C and N; and Q is Cr, Re, Ru, R
one or two selected from h, Ni, Pd, Pt, and Au
And p, q, e, f, and g are at%,
8 ≦ p ≦ 15, 0 ≦ q ≦ 10, 1 ≦ e ≦ 10, 0.5 ≦
It satisfies the relationship of f ≦ 15 and 0 ≦ g ≦ 10. 33. the soft magnetic thin film, a composition formula Co _l T
represented by a _m Hf _n, the preceding claims 23 to form as an amorphous soft magnetic alloy thin film mainly the amorphous structure 28
The method for manufacturing a magneto-impedance effect element according to any one of the above. Here, l, m, and n are at%, and 70 ≦ l ≦ 9.
0, 5 ≦ m ≦ 21, 6.6 ≦ n ≦ 15, 1 ≦ m / n ≦
This satisfies the relationship of 2.5. 34. The soft magnetic thin film having a composition formula of Co _a Z
r _b Nb to claims 23 to form as an amorphous soft magnetic alloy thin film mainly composed of amorphous structure represented by _c 28
The method for manufacturing a magneto-impedance effect element according to any one of the above. Here, a, b, and c are at%, and 78 ≦ a ≦ 9.
1, which satisfies the relationship 0.5 ≦ b / c ≦ 0.8. 35. (g) forming a soft magnetic ribbon by injecting a molten alloy of a soft magnetic material onto a chill roll and quenching the contact; and (h) at least one surface of the soft magnetic ribbon. Forming a conductive thin film made of a material having a lower specific resistance than the soft magnetic ribbon; and (i) cutting the soft magnetic ribbon formed by the step (h) to obtain a predetermined value. (J) forming a pattern at a ratio (aspect ratio) W / L of an element width W to an element length L, and (j) the soft magnetic layer formed by laminating the conductive thin film formed by the step (i). A step of stacking the ribbons so that soft magnetic ribbons and conductive thin films are alternately stacked on a substrate; and (k) a step of heat-treating the soft magnetic ribbons in a static magnetic field in a device width direction. And a method for manufacturing a magneto-impedance effect element comprising: 36. In the step (j), an insulating layer is formed between the soft magnetic ribbon and the conductive thin film, and after the step (j), only the conductive thin film is formed. The method for manufacturing a magneto-impedance effect element according to claim 35, further comprising a step of forming an electrode portion to be connected. 37. The soft magnetic thin film or the soft magnetic thin ribbon
And the composition formula is (Fe _1-aCo_a)_100-xy(Si_1-bB_b)_x
M_yAs an amorphous soft magnetic alloy thin film or ribbon
37. Any of claims 23 to 28, 35, 36 formed
3. The method for manufacturing a magneto-impedance effect element according to claim 1. However
And M is either Cr or Ru, or both
And a and b representing the composition ratio are 0.05 ≦ a
≦ 0.1, 0.2 ≦ b ≦ 0.8, and x and y are at%
Satisfying the relationship of 10 ≦ x ≦ 35 and 0 ≦ y ≦ 7.
is there. 38. A magnitude of the external magnetic field which maximizes an output voltage from both ends of the magnetic sensing unit when an external magnetic field is applied while applying a driving AC current in the element longitudinal direction of the magnetic sensing unit. 4. The magnetically sensitive portion is patterned by setting a ratio (aspect ratio) W / L of an element width W to an element length L so that an absolute value is 400 (A / m) or less.
8. The method for manufacturing a magneto-impedance effect element according to any one of 7. 39. The method of manufacturing a magneto-impedance effect element according to claim 38, wherein the aspect ratio of the magnetically sensitive portion is set to 0.1 or less.