JPH06325934A - Magnetoresistance effect element - Google Patents

Abstract

PURPOSE:To realize a spin valve structured film or an artificial lattice film having excellent soft magnetic characteristics by a method wherein, within at least one ferromagnetic film having non-coupling property mainly comprising at least one element selected from the groups consisting of Co, Fe and Ni, the closest surface thereof is to be oriented in the vertical direction on the film surface. CONSTITUTION:The magnetoresistance effect element is obtained by forming a spin valve structured laminated film successively formed of a Co90Fe10 film 11 as a ferromagnetic film on a sapphire substrate 10, a Cu film 12 as an intermediate non-magnetic film, said film 11 again, an FeMn film 13 as an anti- ferromagnetic film, a Ti film 14 as a protective film. At this time, the thickness of the two Co90Fe10 films 11 as the ferromagnetic films may be either equal or different from each other in practically pertinent thickness of 0.5-20nm. Besides, the crystalline structure of this magnetoresistance effect element is oriented in intensitive fcc phase (111) plane (the closest orientation). Accordingly, the magnetic reluctance effect element can be simultaneously display the high change rate of resistivity and excellent soft magnetic characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive effect element used in a magnetic head or the like.

[0002]

2. Description of the Related Art Conventionally, when reading information recorded on a magnetic recording medium, a reading magnetic head having a coil is moved relative to the recording medium and the coil is generated by electromagnetic induction generated at that time. A general method is to detect the voltage induced in the. It is also known to use a magnetoresistive head for reading information [IEEE MA
G-7,150 (1971)]. This magnetoresistive head utilizes a phenomenon that the electric resistance of a certain kind of ferromagnetic material changes according to the strength of an external magnetic field, and is known as a high-sensitivity head for magnetic recording media. . In recent years, magnetic recording media have been downsized and increased in capacity, and the relative speed between the reading magnetic head and the magnetic recording medium at the time of reading information has become smaller. Therefore, a large output can be obtained even at a small relative speed. Expectations are increasing for magnetoresistive heads that can be taken out.

Conventionally, a NiFe alloy (hereinafter abbreviated as permalloy) has been used in a portion (hereinafter referred to as an MR element) where a resistance changes by sensing an external magnetic field in a magnetoresistive head. Permalloy, even though it has good soft magnetic characteristics, has a maximum magnetoresistance change rate of 3%.
However, the rate of change in magnetoresistance is insufficient when it is used for an MR element for a magnetic recording medium having a small size and a large capacity. Therefore, as the MR element material, a material exhibiting highly sensitive magnetoresistance change is desired.

In recent years, like Fe / Cr and Co / Cu,
A so-called artificial lattice film in which a ferromagnetic film and a non-magnetic film are alternately laminated under a certain condition, a so-called artificial lattice film has a huge magnetoresistance change by utilizing antiferromagnetic coupling between adjacent ferromagnetic films. It has been confirmed that it appears, and it has been reported that it exhibits a large magnetoresistance change rate of more than 100% at the maximum [Phy.
s.Rev.Lett., Vol.61,2472 (1988)] [Phys.Rev.Lett., Vol.
64, 2304 (1990)].

On the other hand, even if the ferromagnetic films are not antiferromagnetically coupled, one of the two ferromagnetic films sandwiching the nonmagnetic film by another means without using antiferromagnetic coupling between adjacent ferromagnetic films. An example in which a large magnetic resistance change was realized by creating an antiparallel state with a non-magnetic film sandwiched between them by applying an exchange bias to them and fixing the magnetization, and by reversing the magnetization of the other ferromagnetic film by an external magnetic field. Have also been reported. This type is called a spin valve structure here [Phys.Rev.B., Vol.
45806 (1992)] [J. Appl. Phys., Vol.69, 4774 (1991)].

In both the artificial lattice film and the film having the spin valve structure, the resistance change characteristic and the magnetic characteristic of the laminated film are considerably different depending on the type of the ferromagnetic film. For example, when Co is used in the spin valve structure, for example, Co / Cu / Co /
In FeMn, a large resistance change rate of 8% occurs, but the coercive force is as high as about 20 Oersted and the soft magnetic characteristics are not good. On the contrary, when permalloy is used, for example, NiFe
In / Cu / NiFe / FeMn, a coercive force of 1 oersted or less is reported as a good value, but the resistance change rate is not as large as about 4% [J.Al.Phys., Vol.69,4774 ( 199
1)]. As described above, the soft magnetic characteristics of the laminated film are good, but the resistance change rate is lowered. Therefore, the constituent elements and film structure of the laminated film satisfying both the soft magnetic characteristics and the rate of change in resistance have not yet been reported.

Further, the two types of membranes have the following problems.

In the artificial lattice film, the resistance change rate ΔR / R ignoring the magnetic field range is larger than that of the spin valve type, but the saturation magnetic field Hs is large and the soft magnetism is difficult due to the large antiferromagnetic coupling. Furthermore, since this RKKY-like antiferromagnetic coupling is sensitive to the interface structure, it is difficult to form a stable film and it is easy to change over time.

In the film having the spin valve structure, the ferromagnetic film is made of N.
Good soft magnetic characteristics can be obtained by using the iFe film, but since there are two interfaces between the ferromagnetic film and the nonmagnetic film, ΔR / R is smaller than that of the artificial lattice film. Even if a multi-layer laminated film is formed by repeatedly laminating a ferromagnetic film, a non-magnetic film, and an antiferromagnetic film in order to increase the number of this interface, the antiferromagnetic film with high resistance exists in this laminated film. Therefore, spin-dependent scattering is suppressed, and an increase in ΔR / R cannot be expected after all.

Further, when a signal magnetic field is applied in the hard axis direction of a ferromagnetic film suitable for a magnetic head, the magnetization rotates only on one side of the ferromagnetic film, and as shown in FIG. The angle formed by the magnetizations of the ferromagnetic film 2 on the film 1 and the ferromagnetic film 4 on the non-magnetic film 3 can be changed only up to about 90 °. Note that an angle change of up to 180 ° occurs in the easy axis direction. As a result, ΔR / R is reduced to about half in the easy axis direction. Here, even if the exchange bias magnetic field of the ferromagnetic film 2 on the antiferromagnetic film 1 is weakened by some method so that the magnetization rotation of both ferromagnetic films 2 and 4 can be utilized, When the film thickness is reduced to increase the rate of resistance change, ferromagnetic coupling works between the two ferromagnetic films.
When the signal magnetic field is 0, the magnetizations between the ferromagnetic films are oriented in the same direction. As a result, even if the magnetization is rotated by the signal magnetic field, the angle change of the magnetization between the two ferromagnetic films is small and the resistance change is small.

Further, there is a problem that the ferromagnetic coupling between the two ferromagnetic films, which works when the thickness of the nonmagnetic film is reduced, deteriorates the magnetic permeability of the ferromagnetic film. In addition, the NiFe film having good soft magnetic characteristics has a usual anisotropic magnetoresistive effect, but in the method of flowing the sense current in the direction perpendicular to the signal magnetic field, as shown in FIG. With the magnetizations of the two ferromagnetic films aligned in the same direction, the anisotropic magnetoresistive effect due to the signal magnetic field and the resistance change due to spin-dependent scattering cancel each other out.

[0012]

The common problems of the artificial lattice film and the film of the spin valve structure are as follows. First, in order to obtain high sensitivity in the magnetic head, it is necessary to increase the supplied current as much as possible. However, in this case, in both films, the direction of magnetization of some of the ferromagnetic films is disturbed by the magnetic field generated by this current, and the resistance change with high sensitivity to the magnetic field is prevented. Specifically, in the vicinity of the uppermost layer and the lowermost layer of the laminated film, the current magnetic field is strong, and the magnetization easily tends to the current magnetic field direction.

Secondly, there is an important problem to be solved when applied to a magnetic head such as Barkhausen noise suppression and operating point bias.

As described above, a magnetoresistive effect element having an artificial lattice film utilizing spin-dependent scattering or a film having a spin valve structure exhibits good soft magnetic characteristics even when a large current is applied, which is essential for high sensitivity. And a large resistance change rate ΔR /
At present, it is impossible to indicate R.

The present invention has been made in view of the above points and has a spin valve structure film or an artificial lattice film having a good soft magnetic property and a sufficient resistance change rate ΔR / R, and has a high sensitivity. An object of the present invention is to provide a magnetoresistive effect element applicable to a head.

[0016]

The present invention, which has been made to achieve the above objects and objects, achieves a magnetoresistive effect having a spin valve structure film as shown in FIG. 1 or an artificial lattice film as shown in FIG. The present invention relates to an element and has a basic structure in which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially stacked on a substrate. Here, the material of the ferromagnetic film is C unless otherwise specified.
o, CoFe, CoNi, NiFe, sendust, Ni
FeCo, Fe ₈ N and the like can be mentioned. further,
Ferromagnetic film made of _{Co 100-x Fe x (0} <x ≦ 40 atomic%) is preferred because exhibit high △ R / R at a low Hc.
The thickness of the ferromagnetic film is preferably 1 to 20 nm. In the present invention, ferromagnetism means ferrimagnetism. Further, as the material of the non-magnetic film, Mn, Fe, N
i, Cu, Al, Pd, Pt, Rh, Ru, Ir, A
u, non-magnetic metal such as Ag, CuPd, CuPt,
CuAu, CuNi alloy, etc. can be mentioned. The thickness of the non-magnetic film is preferably 0.5 to 20 nm,
Particularly preferably, it is 0.8 to 5 nm.

The magnetoresistive effect element of the present invention will be specifically described below.

A first invention of the present invention is a magnetoresistive effect element comprising a laminated film having at least a ferromagnetic film, a nonmagnetic film and a ferromagnetic film sequentially laminated on a substrate,
The two ferromagnetic films are non-bonded, and at least one of the ferromagnetic films contains at least one element selected from the group consisting of Co, Fe, and Ni as a main component, and the close-packed surface thereof is a film. Provided is a magnetoresistive effect element characterized by being oriented in a direction perpendicular to a plane.

In the first invention, the fact that the two ferromagnetic films are non-coupled means that there is substantially no antiferromagnetic exchange coupling between the two ferromagnetic films. Therefore,
In the case of realizing antiparallel magnetization arrangement states in the two ferromagnetic films, a means different from the antiferromagnetic coupling between the ferromagnetic films is formed as a bias magnetic field applying means to the ferromagnetic films. Further, the close-packed plane orientation is (11
1) plane, and in the case of hcp phase, it means (001) plane.

In the first invention, as a method of orienting the close-packed surface of the ferromagnetic film in a direction perpendicular to the film surface, Pd, Al, Cu, Ta, In, B, N is added to the material of the ferromagnetic film.
b, Hf, Mo, W, Re, Ru, Rh, Ga, Zr,
A method of adding at least one element selected from the group consisting of Ir, Au, and Ag (particularly, addition of Pd, Cu, Au, and Ag that causes almost no decrease in resistance change rate), a ferromagnetic film A method of using the C plane of a sapphire substrate as a substrate to be formed, Cu between the substrate and the ferromagnetic film,
Material having fcc lattice such as Ni, CuNi, NiFe, Ge, Si, GaAs, material having rhombohedral lattice such as NiO, Ti, magnetic amorphous metal (CoZrNb, CoH)
fTa) and a non-magnetic amorphous material, and a method of providing a base film made of a material selected from the group consisting of non-magnetic amorphous materials, and MBE
A method of forming a film by an ultra-high vacuum film forming apparatus such as

Here, a specific example of the underlayer film will be described in detail. For example, in the case of a Co type ferromagnetic film, when a ferromagnetic film having an fcc lattice represented by a Co ₉₀ Fe ₁₀ film is used, Cu--Ge is used. -Zr, Cu-P, Cu-P-Pd, C
u-Pd-Si, Cu-Si-Zr, Cu-Ti, Cu
Cu-based alloys represented by -Sn and Cu-Ti-Zr,
Au-Dy, Au-Pb-Sb, Au-Pd-Si, A
Au-based alloys represented by u-Yb, Al-Cr, Al
-Dy, Al-Ga-Mg, Al-based alloys represented by Al-Si, Pt-based alloys, Pd-based alloys represented by Pd-Si, Pd-Zr, Be-Ti, Be-Ti-Z.
r, Be-based alloys such as Be-Zr, Ge-Nb, Ge-P
Ge-based alloys represented by d-Se, Ag-based alloys, Rh
Fc of system alloys, Mn system alloys, Ir system alloys, Pb system alloys, etc.
c-lattice-based metal-based materials, alloys containing these fcc-lattice-based metals as a main component, Ge, Si, materials having a diamond structure such as diamond, GaAs, Ga
-Al-As, Ga-P, In-P, and other materials having a zinc blende type structure are listed as the material having the fcc lattice, and a material containing at least one selected from these as a main component. Alternatively, it is possible to use a material or the like in which other elements are added. Among the above-mentioned materials, the substances other than the single element metal have already a sufficiently high specific resistance as compared with the ferromagnetic film, and thus have an effect of suppressing the current of the shunt shunt current. In addition, there are various combinations of the increase in the specific resistance due to the addition of other elements to the single element metal, but Cu-based alloys represented by Cu-Ni, Cu-Cr, and Cu-Zr, Au-Cr, Fe-Mn, Pt-M
Alloys such as n and Ni-Mn are given as an example.

Examples of the non-magnetic amorphous material include non-magnetic single-element metals and alloys, non-magnetic metal materials such as those containing non-metals as additives, and amorphous Si such as hydrogenated Si.
Non-magnetic non-metallic materials such as hydrogenated carbon, glassy carbon, and amorphous carbon such as graphitic carbon can be used.

The thickness of the above-mentioned base film is not particularly limited, but is preferably 100 nm or less. This is because, if the thickness of the base film is too thick, no further effect can be obtained, but conversely, the ratio of the current flowing through the base film in the entire element is large, and as a result, the resistance change rate becomes small. is there. In the first invention, the underlayer improves the close-packed plane orientation of the ferromagnetic film. Further, among the above-mentioned materials, non-magnetic amorphous materials can be grown in layers regardless of the substrate material and a stable and smooth surface can be obtained. Thus, the surface smoothness of the ferromagnetic film formed thereon and the smoothness of the interface with the nonmagnetic film can be improved. Therefore, it is possible to stably obtain a good resistance change rate. Further, when a non-magnetic material is used as the base film in the first invention, it does not adversely affect the ferromagnetic film formed thereon.

When forming the base film, the crystal orientation is improved, but the smoothness may be deteriorated and the resistance change rate may be lowered. Therefore, when a material having an fcc lattice or a magnetic amorphous metal is used as the material of the first underlayer film for promoting the close-packed plane orientation, Ti, Ta, Z
It is preferable that the second underlayer film made of r or a non-magnetic amorphous material for improving smoothness has a two-layer structure arranged between the first underlayer film and the substrate. With such a structure, it is possible to obtain a magnetoresistive effect element having both excellent soft magnetic characteristics obtained by improving the close-packed plane crystal orientation and a high magnetoresistance change rate. Also, in the two-layer structure,
By using the second underlayer film having the same crystal system as that of the ferromagnetic film and having a specific resistance larger than that of the ferromagnetic film material, in addition to the above effects, the shunt current component in the current flowing in the element is increased. Can be reduced. When the base film is used as a laminated structure of two or more layers, it is desirable that the thickness of the laminated structure does not exceed 100 nm.

As a method of forming the above-mentioned base film, a bipolar sputtering method using a high frequency discharge of 13.56 MHz or 100 MHz or more, an ion using various ion sources such as an ECR ion source and a Kauffman type ion source. Various film forming methods such as beam sputtering method, vacuum evaporation method using electron beam evaporation source and Knudsen cell, thermal CVD method, CVD method using various plasmas, MOCVD method using organic metal as a raw material, and MOMBE method are applied. can do. As common to these film forming methods, it is important to manage water and oxygen by exhausting to ultra-high vacuum and ultra-purifying the source gas. More specifically,
The content of H ₂ O and O ₂ should be below ppm, preferably pp
It is preferable to reduce to the b order.

In the first invention, it is preferable to use a Co type alloy as the material of the ferromagnetic film. The reason for this is that in a system not containing Co, the resistivity change ΔR / R of the obtained magnetoresistive effect element is about 4%, which is lower than that in the case of a Co-based alloy, and in the case of a Co single-element metal, the closest packed surface Due to the large magnetocrystalline anisotropy that Co has even if orientation is realized,
This is because the soft magnetic properties may not be improved so much. At this time, in particular, Co _100-x Fe _x (5 ≦ x ≦ 40
Atomic%) is 10% due to the fcc phase (111) orientation
It is preferable because it exhibits the above high ΔR / R and low Hc of less than 80 A / m.

Regarding the crystal orientation of the ferromagnetic film, the full width at half maximum of the rocking curve of the close-packed plane (for example, fcc phase (111) plane) reflection peak in the X-ray diffraction curve is less than 20 °, particularly 7
It is preferably not more than °.

In the first invention, the addition content of the additional element is such that the ferromagnetism of the ferromagnetic film containing a CoFe alloy or the like as the main component is not impaired at room temperature, and an intermetallic compound which inhibits spin-dependent scattering is produced. It must be within the range not covered. For example, when the additive elements are Al, Ga and In, the content is preferably less than 6.5 at%. When the additive elements are Nb, Ta, Zr, Hf, B, Mo and W, the content is preferably less than 10 at%. Additive elements are Cu, Pd, Au, Ag, Re, Ru, Rh, Ir
When it is, the content is preferably less than 40 at%.

The substrate material is MgO, sapphire, diamond, graphite, silicon, germanium, SiC, BN, SiN, AlN, BeO, Ga.
Single crystal bodies represented by As, GaInP, GaAlAs, BP, etc., and their polycrystal bodies and sintered bodies containing them as the main components, single crystal bodies, polycrystal bodies, and sintered bodies of magnetic or non-magnetic metals. As a typical example, the substrate material is selected according to the type of ferromagnetic film and the material of the underlying film. In particular, it is preferable to use the C plane of the sapphire substrate, which has good lattice matching with the Co-based alloy and has a feature that a smooth plane can be easily obtained. When using a single crystal substrate such as a sapphire substrate, the thickness of the ferromagnetic film is preferably 20 nm or less. This is because the ferromagnetic film has a thickness of 20.
This is because the densest plane orientation deteriorates when the thickness exceeds nm.

Here, in the above-mentioned magnetic film having the closest packing plane orientation,
When the magnetization direction is slightly tilted from within the close-packed plane, Hc rapidly increases. Therefore, if the substrate surface has a waviness, the magnetization direction may deviate from the (111) plane even if the close-packed plane orientation is realized, so that Hc may not decrease. Therefore, the surface roughness of the substrate is preferably less than 5 nm.
The magnetoresistive effect element of the first invention may have a structure in which a nonmagnetic film and a ferromagnetic film are alternately laminated a plurality of times in addition to the above structure.

In the first invention, the most dense surface of the ferromagnetic film containing at least one element selected from the group consisting of Co, Fe, and Ni as a main component, for example, fcc phase (11
1) Good soft magnetic properties can be obtained by orienting the planes in the direction perpendicular to the film plane. This is because the easy axis of magnetization depending on the magnetocrystalline anisotropy K ₁ does not appear in the fcc phase (111) plane. Also, by controlling the surface roughness of the substrate on which the ferromagnetic film is formed, the magnetization in the ferromagnetic film can be preserved in the close-packed plane, which reduces the coercive force due to the magnetocrystalline anisotropy. Can be made. Therefore, better soft magnetic characteristics can be obtained. Further, the coercive force (Hc) is set to 1 by orienting the rocking curve full width at half maximum to be less than 20 °, preferably 7 ° or less.
Good soft magnetic characteristics up to 00 A / m, high resistance change rate (ΔR / R) (for example, CoR film, ΔR / R for non-oriented films and other orientations (for example, fcc phase (100) orientation))
It is possible to obtain a highly sensitive magnetoresistive effect element having both high magnetic permeability and high magnetic permeability.

Here, the normal to the main crystal orientation plane of the laminated film has a component in the film plane due to the fluctuation of the crystal orientation plane,
The in-plane component of the film has anisotropy, or the normal of the plane defect generated in the crystalline laminated film has fluctuations in the film plane, and this fluctuation causes anisotropy in the film plane. I may have. The direction in which such anisotropy is strong is a direction in which ferromagnetic atoms and nonmagnetic atoms are likely to be mixed on the atomic plane where the film grows. Therefore, it is considered that the probability of electrons being spin-dependent scattered at the interface is increased by flowing the sense current in this direction, that is, in the direction in which the anisotropy due to the in-plane component of the film is maximized.

That is, when the crystal orientation plane of the ferromagnetic film of the laminated film is fluctuated or the surface arrangement is introduced to disturb the atomic arrangement, the atomic arrangement in the crystal orientation surface is disturbed. By passing a sense current in the direction of large turbulence, electrons equivalently pass through many interfaces and ferromagnetic films, and the probability of spin-dependent scattering increases. In this way, by setting the direction of the sense current to the direction along the fluctuation direction of the crystal orientation plane of the laminated film,
The magnetoresistive effect element exhibits a larger rate of resistance change.

A second aspect of the present invention is a magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a nonmagnetic film, and a ferromagnetic film are sequentially laminated on a substrate, and at least one of the ferromagnetic films. The film contains at least two elements selected from the group consisting of Co, Fe, and Ni as main components, and P
d, Al, Cu, Ta, In, B, Nb, Hf, Mo,
There is provided a magnetoresistive effect element having a composition containing at least one element selected from the group consisting of W, Re, Ru, Rh, Ga, Zr, Ir, Au, and Ag.

The magnetoresistive effect element of the second invention may be one in which a nonmagnetic film and a ferromagnetic film are alternately laminated a plurality of times in addition to the above structure.

In the second invention, the added content of the additional element is such that an intermetallic compound that does not impair the ferromagnetism of the ferromagnetic film containing CoFe alloy as a main component at room temperature and inhibits spin-dependent scattering is formed. It must be within the range not covered. For example, when the additive elements are Al, Ga and In, the content is preferably less than 6.5 at%. When the additive elements are Nb, Ta, Zr, Hf, B, Mo and W, the content is preferably less than 10 at%. Additive elements are Cu, Pd, Au, Ag, Re, Ru, Rh, Ir
When it is, the content is preferably less than 40 at%.

In the second aspect of the present invention, by adding the above-mentioned additive element, the Hc is up to 100 A / m, the excellent soft magnetic characteristics and the high sensitivity magnetic resistance having ΔR / R of 5% or more. An effect element can be obtained. In particular, the addition of Al, Ta, Zr, Nb and Hf significantly improves the soft magnetic characteristics. In this case, the reason why the soft magnetic characteristics are improved is not clear so far, but it is considered that the effect of reducing the crystal magnetic anisotropy is included in addition to the effect of improving the crystal orientation. Furthermore, Pd, Cu, A
With g and Au, intermetallic compounds are not generated even if added in a large amount up to about 40 at% and the lattice constant becomes large, so that the lattice matching with the intermediate non-magnetic film such as Cu becomes good. The increase of spin-dependent scattering due to so-called bulk scattering can be expected. Therefore, high ΔR / R can be maintained in addition to improvement of soft magnetic characteristics.

A third invention is a laminated film in which a ferromagnetic film of (n + 1) layers and a nonmagnetic film of n layers are alternately formed on a substrate (where n is an integer of 1 to 4). ), The resistivity is 5 adjacent to at least one of the uppermost layer and the lowermost ferromagnetic film of the laminated film.
There is provided a magnetoresistive effect element characterized in that a ferromagnetic film having a thickness of 0 μΩcm or more is further laminated.

In the third invention, the resistivity is 50 μΩcm.
The high resistance ferromagnetic film described above may be either a ferromagnetic film or a ferrimagnetic film. In addition, the reason why the ferromagnetic film is a laminated film having five or less laminated layers is that when the number of interfaces of the ferromagnetic film / non-magnetic film increases, the action of the interface of the high resistance ferromagnetic film / ferromagnetic film becomes relatively large. This is because ΔR / R is not improved and ΔR / R is not improved. Therefore, the third invention is suitable for the magnetoresistive effect having the film of the spin valve structure.

As described above, by laminating the ferromagnetic film so that the high-resistance ferromagnetic film is in contact with the ferromagnetic film, it is possible to suppress the generation of magnon at the boundary surface. As a result, it is possible to reduce the probability of electron spin reversal due to collision between magnon and electron, which makes it possible to increase the rate of resistance change at room temperature and realize a highly sensitive magnetoresistive effect element. . However, if the resistivity of the high-resistance ferromagnetic film is less than 50 μΩcm, the current mainly flows in the high-resistance ferromagnetic film, and conversely the resistance change rate decreases. In other words, by using a ferromagnetic film having a resistivity of 50 μΩcm or more, it is possible to prevent current from being taken by the high-resistance ferromagnetic film and suppress a decrease in magnetoresistance change rate due to the shunt effect.

As the material of the high resistance magnetic film, Ni, F
e, Co, NiFe, NiFeCo, CoFe, Co alloy, etc., Ti, V, Cr, Mn, Zn, Nb, Tc, H
Examples include those to which elements such as f, Ta, W, and Re have been added.

In the third invention, the high resistance ferromagnetic film is
It is preferably a high resistance soft magnetic film. At this time, by adjoining the adjacent ferromagnetic film and the high resistance soft magnetic film, the high resistance soft magnetic film, for example, the amorphous film having good soft magnetic characteristics is rotated by the magnetization of the ferromagnetic film. The magnetization also rotates likewise. This improves the soft magnetic properties of the ferromagnetic film.

As the high resistance soft magnetic film, a high resistance amorphous film made of CoZrNb or the like, a microcrystalline high resistance soft magnetic film made of FeZrN, CoZrN or the like, or X in RFe, Nb, Zr, Hf in NiFeX is used. Ta, Re, I
r, Pd, Pt, Cu, Mo, Mn, W, Ti, Cr,
A film made of a material that is any one element selected from the group consisting of Au and Ag can be used. Among these, amorphous films, CoZrN, NiFeNb
When a film made of a material having an fcc phase composed of, for example, is formed adjacent to the lowermost ferromagnetic film, the fcc of the ferromagnetic film above it is formed.
This is more preferable because the (111) orientation is promoted.

The thickness of the high resistance ferromagnetic film is preferably 0.5 nm or more. This is because if the film thickness is less than 0.5 nm, the magnetism of the high resistance ferromagnetic film itself becomes weak and it becomes difficult to suppress the generation of magnon. On the other hand, when the soft magnetic property of the high resistance ferromagnetic film is inferior to the soft magnetic property of the adjacent ferromagnetic film, the film thickness of the high resistance ferromagnetic film is preferably 10 nm or less. This has a film thickness of 1
This is because if it exceeds 0 nm, it affects the magnetization process of the ferromagnetic film, and it becomes difficult to obtain soft magnetic characteristics.

A fourth aspect of the invention is a laminated film (where n is 1 to 4) in which a ferromagnetic film of (n + 1) layers and a first nonmagnetic film of n layers are alternately formed on a substrate. The thickness of at least one of the uppermost and lowermost ferromagnetic films of the laminated film is 5 nm or less, and the thickness is 5 nm or less. A magnetoresistive effect element characterized in that a second non-magnetic film having a resistivity not more than twice that of the ferromagnetic film is further formed adjacent to the above.

In the fourth invention, the material of the second nonmagnetic film preferably has the same crystal structure as the material of the adjacent ferromagnetic film. That is, when the ferromagnetic film is made of a material having the fcc phase, the first non-magnetic film is also preferably made of a material having the fcc phase. At this time, the difference in lattice constant between the material of the second non-magnetic film and the material of the ferromagnetic film is 5
It is preferably within%. In particular, when the second non-magnetic film is formed adjacent to the lowermost ferromagnetic film, by increasing the crystal matching between the ferromagnetic film and the second non-magnetic film,
It is possible to epitaxially grow the ferromagnetic film, and thus it is possible to suppress electron scattering at the interface.

Specifically, the material of the second non-magnetic film is Mn, Fe, Ni, Cu, Al, Pd, Pt, R.
A material containing at least one element selected from the group consisting of h, Ir, Au, and Ag as a main component can be used. A base film may be interposed between the substrate and the second nonmagnetic film.

In the fourth invention, it is desirable that the crystal grains of the material forming the ferromagnetic film have a large crystal grain size in the film thickness direction so that the crystal growth is not hindered in each ferromagnetic film.
If the ferromagnetic film exceeds five layers, the number of interfaces between the ferromagnetic film and the nonmagnetic film may increase, and the spin-dependent scattering effect may be substantially lost. Is 5 layers or less.

In the fourth invention, the thickness of the second nonmagnetic film is preferably in the range of 0.2 to 20 nm. This means that if the thickness of the second non-magnetic film is less than 0.2 nm,
The probability that electrons flowing into the second non-magnetic film will undergo inelastic scattering at the interface with the substrate increases, making it difficult to effectively extend the mean free path. Conversely, if the film thickness exceeds 20 nm. However, this is because no further effect can be obtained, and the current flowing only through the second nonmagnetic film increases, making it difficult to obtain a large resistance change rate.

When the magnetoresistive effect element of the fourth invention is applied to a sensor, the material of the second non-magnetic film should be a plate-like body which is not more than twice as large as the material of the ferromagnetic film such as CoFe alloy. Is required, and it is preferable that the resistivity is smaller than that of the ferromagnetic film. This is because when the resistivity of the second non-magnetic film is significantly higher than that of the ferromagnetic film, the electrons flowing into the second non-magnetic film are scattered and the effective mean free path can be maintained for a long time. This is because the resistance change rate cannot be expected to increase. Further, it is desirable that the material of the second non-magnetic film has a resistivity that is ¼ or more of the resistivity of the ferromagnetic film. This is because if the resistivity of the second non-magnetic film material is less than ¼ of the resistivity of the ferromagnetic film, the current easily flows only in the second non-magnetic film.

According to the fourth aspect of the invention, by stacking the second non-magnetic film adjacent to at least one of the ferromagnetic films, even if the thickness of the ferromagnetic film is reduced to 5 nm or less, It takes advantage of the fact that the effective mean free path of electrons can be kept for a long time. For example, in a film having a spin valve structure, as the thickness of the ferromagnetic film is reduced, the specific resistance increases and the rate of resistance change decreases. Therefore, by thinning the ferromagnetic film and at the same time stacking the second nonmagnetic film in contact with the thinned ferromagnetic film, the electrons are not subjected to inelastic scattering on the surface of the ferromagnetic film, and the second nonmagnetic film It becomes possible to flow into the film, and the ferromagnetic film can be thinned while keeping the effective mean free path long. At this time, in order to obtain the above effects, the number of stacked ferromagnetic films must be 5 or less.

As described above, in the fourth invention, the second non-magnetic film is laminated in contact with the ferromagnetic film, so that the thickness of the ferromagnetic film, which usually causes a remarkable decrease in resistance change rate, is 5 nm or less. Even in the case, a magnetoresistive effect element having a large resistance change rate can be obtained. Moreover, by making the thickness of the ferromagnetic film as thin as 5 nm or less, it is possible to suppress the domain wall generation due to the demagnetizing field even if the ferromagnetic film is processed into a fine shape for high density magnetic recording / reproduction with a narrow track width. Therefore, it is possible to suppress the generation of Barkhausen noise without lowering the detection sensitivity of the signal magnetic field. As a result, it is possible to realize a magnetoresistive effect element with little noise and high sensitivity, which is suitable for reproduction of high-density recording.

The magnetoresistive element of the fourth invention is
It may have either a spin valve structure film or an artificial lattice film. However, in the spin-valve magnetoresistive effect element, it is preferable that the second ferromagnetic film is laminated and formed adjacent to the ferromagnetic film whose magnetization is not fixed by the antiferromagnetic film or the like.

A fifth aspect of the present invention is a magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film and a ferromagnetic film are sequentially laminated on a substrate. Provided is a magnetoresistive effect element characterized in that a thin film having a larger resistivity and a longer mean free path than that of the ferromagnetic film is further formed adjacent to at least one of the upper and lowermost ferromagnetic films. .

In the fifth invention, examples of the material of the thin film include semimetals such as Bi, Sb and carbon, semiconductors degenerated by high concentration doping, oxide semiconductors such as SnO ₂ and TiO ₂ . The thickness of the thin film is 1 to 50.
It is preferably in the range of nm. This is because if the thickness of the thin film is less than 1 nm, the effect of increasing the mean free path of electrons cannot be sufficiently obtained, and even if the thickness exceeds 50 nm, no further effect can be obtained and only the thin film flows. This is because the current increases and it becomes difficult to obtain a large resistance change rate. Furthermore, if the resistivity of the thin film is smaller than the resistivity of the ferromagnetic film, the current mainly flows in the thin film, and the magnetoresistive effect is reduced on the contrary. Therefore, the thin film has a higher resistivity than the ferromagnetic film. To have.

In the fifth invention, the mean free path means an average distance that electrons move without being scattered by other objects.

In the fifth invention, the thickness of the ferromagnetic film is
When it is in contact with the thin film, it is preferably 5 nm or less for the same reason as in the fourth invention, and the ferromagnetic film not in contact with the thin film is preferably in the range of 2 to 20 nm in order to secure the mean free path.

In the fifth aspect of the invention as described above, the effective mean free path of the entire laminated film can be lengthened by laminating thin films having a long mean free path in contact with at least one ferromagnetic film. Are using. For example, the following is known as the physical mechanism of the magnetoresistive effect in the spin valve type laminated film. That is, in the spin-valve type laminated film, when the magnetization directions between the two ferromagnetic films are parallel to each other, conduction electrons having either spin parallel to the magnetization or spin antiparallel to the magnetization are generated in the film. It becomes possible to have a long mean free path as a whole, and shows a low specific resistance value as a whole. On the other hand, when the magnetization directions of the two ferromagnetic films are antiparallel to each other, conduction electrons having a long mean free path do not exist in the entire film, and the specific resistance value increases. The magnetoresistive effect in the spin valve type laminated film is determined by the difference in the length of the mean free path in these two states.

Further, it is known that electrons having spins parallel to the magnetization and electrons having antiparallel spins in the ferromagnetic film have different mean free paths. For the reason, electrons in the spin direction having a long mean free path inside the ferromagnetic film can have a larger magnetoresistive effect in the spin-valve type laminated film if the electron has a longer mean free path. Therefore, in the fifth invention, by stacking thin films having a mean free path longer than that of the ferromagnetic film, it is possible to lengthen the effective mean free path of electrons and further increase the magnetoresistive effect. There is. However, if the specific resistance of the thin film is smaller than that of the ferromagnetic film, the current mainly flows in the stacked thin films, and the magnetoresistive effect is reduced. Therefore, it is necessary that the constituent material of the thin film has a long mean free path and a resistivity equal to or higher than that of the ferromagnetic film.

Further, as the thin film having a long mean free path, a material having a large resistivity is used, and the thickness of the ferromagnetic film in contact with the thin film is thinned to increase the specific resistance value of the entire laminated film. It will be possible. As a result, a laminated film having a high specific resistance value can be obtained, and a large signal voltage can be taken out with a low current density even in a fine pattern. Therefore, it is possible to avoid problems such as heat generation and migration.

The magnetoresistive element of the fifth invention is
In addition to the above structure, a nonmagnetic film and a ferromagnetic film may be alternately laminated a plurality of times.

A sixth aspect of the present invention is a magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film and a ferromagnetic film are sequentially laminated on a substrate, wherein A magnetoresistive effect element characterized in that a lower ferromagnetic film is made of a CoFe alloy, and an underlying film having an fcc phase having a lattice constant larger than that of a CoFe alloy is further formed adjacent to the ferromagnetic film. provide.

In the sixth invention, the ferromagnetic film formed on the underlying film having the fcc phase having a large lattice constant is Co.
Low Hc is realized when it consists of Fe alloy, especially Co
Improvement of soft magnetic properties is remarkable for the ferromagnetic film made of a _{100-x Fe x (5 ≦} x ≦ 40 atomic%). This is Fe
This is because if the concentration is less than 5 atomic%, the hcp phase is mixed, and conversely, if the Fe concentration exceeds 40 atomic%, the bcc phase is mixed and lattice mismatch occurs. Other elements that can be added to CoFe include Pd, Al, Cu, Ta and I.
n, B, Zr, Nb, Hf, Mo, Ni, W, Re, R
u, Ir, Rh, Ga, Au, Ag can be mentioned, and even when these elements are added and contained, the same Hc
Reduction is realized.

In the sixth invention, the base film is not limited as long as it is a material having an fcc phase and a lattice constant larger than CoFe, but a material having a resistivity higher than that of the CoFr alloy forming the ferromagnetic film is used. It is preferable to use. Specifically, Cu, Pd, Al or the like, Ni, an alloy containing them as a main component, or a ferromagnetic material having an fcc phase can be used. If the thickness of this base film is one atomic layer or more, Hc can be reduced.
It is preferably 0 nm or less. However, the base film is Cu
When a material having a low resistivity such as is used, the sense current is likely to be shunted to the base film, so that the film thickness is particularly preferably 2 nm or less. Further, a film for improving smoothness is preferably formed between the substrate and the base film,
As a film for improving smoothness, Cr, Ta, Zr, T
A film made of i or the like can be used.

In the sixth aspect of the invention, the ferromagnetic film of Co _100-x Fe _x (0 <x <10 is formed on the underlying film made of a material having the fcc phase and a lattice constant larger than that of the material of the ferromagnetic film.
When the (0 atomic%) film is formed, an appropriate lattice strain is induced in the CoFe film, and as a result, Hc is significantly reduced and good soft magnetic characteristics are exhibited. The lattice strain can be easily controlled by adjusting not only the type of the base film but also the film thickness of the ferromagnetic film, the film thickness of the base film, and the like. Therefore, when a non-magnetic film such as Cu, a ferromagnetic film having a spin-dependent scattering ability such as a CoFe film, and an antiferromagnetic film are sequentially formed on this ferromagnetic film, a large change in resistance is caused by a slight signal magnetic field. It becomes a highly sensitive magnetoresistive effect element. Here, if the resistivity of the base film formed on the substrate is higher than that of the ferromagnetic film, shunting of the sense current to the base film can be suppressed, and a high resistance change rate is exhibited. Further, when the smoothness at each interface is deteriorated and the resistance change rate is lowered because the underlayer film does not grow in a layered manner, another underlayer film having a function of growing the layered film is formed as described above. By interposing it between the base film and the substrate, a high resistance change rate can be realized. In addition,
The magnetoresistive effect element of the sixth invention may have a structure in which a nonmagnetic film and a ferromagnetic film are alternately laminated plural times in addition to the above structure.

A seventh aspect of the present invention is a magnetoresistive effect element comprising a substrate, on which at least a ferromagnetic film, a first non-magnetic film, and a ferromagnetic film are sequentially laminated. Adjacent to the main surface of the ferromagnetic film opposite to the first nonmagnetic film, second nonmagnetic films and ferromagnetic films having different thicknesses from the first nonmagnetic film are alternately formed. The magnetoresistive effect element is characterized in that the magnetizations of the respective ferromagnetic films in the unit laminated film composed of these ferromagnetic films and the second ferromagnetic film are ferromagnetically coupled to each other. I will provide a.

In the seventh invention, at least the second nonmagnetic film and the ferromagnetic film may be formed adjacent to the ferromagnetic films formed on both sides of the first nonmagnetic film.
One side of the first non-magnetic film may be a single-layer ferromagnetic film. It is also possible to form a unit laminated film by alternately forming two or more cycles of the second non-magnetic film and the ferromagnetic film adjacent to the main surface of the ferromagnetic film opposite to the first non-magnetic film. Is. Here, the thickness of the second non-magnetic film in the unit laminated film is preferably 2 nm or less, and further, the thickness is such that ferromagnetic films adjacent to each other do not cause RKKY-like antiferromagnetic coupling. It is preferable. This is to keep the magnetization of each ferromagnetic film in the unit laminated film in a ferromagnetically coupled state. For example, when the material of the ferromagnetic film is CoFe and the material of the second non-magnetic film is Cu, the thickness of the second non-magnetic film is set not to be near 1 nm.

Further, the ferromagnetic film and the second non-magnetic film are grown while maintaining lattice matching, that is, the ferromagnetic film and the second non-magnetic film are lattice-matched and extra scattering occurs at the interface between them. It is desirable that there is no This can prevent an increase in resistance.

In the seventh invention, the unit laminated film including the ferromagnetic film and the second nonmagnetic film has good soft magnetic characteristics, good lattice matching, and is ferromagnetically coupled. Therefore, the resistance is smaller than that in the antiferromagnetically coupled state, and the number of interfaces between the ferromagnetic film and the nonmagnetic film that causes spin-dependent scattering is large.
Therefore, an increase in resistance change rate due to so-called bulk scattering in the unit laminated film can be expected. Therefore, an artificial lattice film or a film having a spin valve structure using this unit laminated film as a ferromagnetic film unit has good soft magnetic characteristics and exhibits a high resistance change rate due to spin-dependent scattering. As a result, a highly sensitive magnetoresistive effect element can be obtained.

The magnetoresistive effect element of the seventh invention is
In addition to the above structure, the first non-magnetic film and the unit laminated film or the ferromagnetic film may be alternately laminated plural times. The magnetoresistive effect element of the seventh invention may have either a spin valve structure film or an artificial lattice film.

An eighth aspect of the present invention is a magnetoresistive effect element comprising a laminated film formed by sequentially laminating a ferromagnetic film, a nonmagnetic film and a ferromagnetic film on a substrate, wherein at least one of the ferromagnetic films is A bias film is formed as a bias magnetic field applying means to the film, the bias film being formed adjacent to or in the vicinity of the laminated film, and the bias magnetic fields in the directions in which the track width direction components are antiparallel to each other in the two ferromagnetic films. Is applied, the magnetizations of the two ferromagnetic films rotate in opposite directions due to a signal magnetic field, thereby providing a magnetoresistive effect element.

In the eighth invention, as a method for applying a bias magnetic field in which the magnetizations of the two ferromagnetic films rotate opposite to each other by a signal magnetic field, a method of forming a bias film adjacent to or in the vicinity of a laminated film, More specifically, a method using exchange coupling from an antiferromagnetic film, a method using a hard magnetic film, and an exchange bias generated by stacking a new ferromagnetic film on a ferromagnetic film having spin-dependent scattering ability are used. The method and the like, and further, a method utilizing a bias magnetic field generated by a sense current and a magnetostatic coupling (demagnetizing field) generated at the time of fine pattern processing are adopted. However, a bias magnetic field is applied by forming the above-described bias film on at least one of the ferromagnetic films. Specifically, for example, an antiferromagnetic film is laminated adjacent to two ferromagnetic films, and the antiferromagnetic film is used so that the directions of the bias magnetic fields are different by 180 ° between the adjacent ferromagnetic films. Magnetize each ferromagnetic film. The magnetization in this case is 180 ° in the direction in which a static magnetic field is applied during the formation of the ferromagnetic film and the antiferromagnetic film.
It can be achieved by changing. Here, it is preferable that the bias magnetic field applied to the adjacent ferromagnetic films has a minimum magnitude necessary for making the ferromagnetic films into a single magnetic domain, for example, 5 kA / m or less. Further, both antiferromagnetic films preferably have different nail points in order to easily apply bias magnetic fields in different directions to the two ferromagnetic films.

Alternatively, there is the following method. To apply the bias magnetic field to one of the ferromagnetic films, an exchange bias magnetic field formed by stacking with the antiferromagnetic film is used. On the other hand, when a bias magnetic field is applied to another ferromagnetic film, a new ferromagnetic film is laminated adjacent to the main surface of the antiferromagnetic film on the opposite side of the ferromagnetic film, A magnetostatic coupling magnetic field (demagnetizing field) generated when a new ferromagnetic film whose magnetization is fixed by is processed into a fine pattern is used. The new ferromagnetic film is a ferromagnetic film A (for example, NiFe or CoFe) suitable for applying an exchange bias in order from the side in contact with the antiferromagnetic film.
Film having good crystallinity) and another ferromagnetic film B suitable for generating a magnetostatic coupling magnetic field (for example, a Co-based amorphous ferromagnetic film, a nitriding or carbide microcrystalline ferromagnetic film, etc. It is desirable to have a two-layer structure in which (1) is laminated so as to be ferromagnetically exchange coupled. In this two-layer structure, the magnetostatic field is adjusted by adjusting the Bs and the resistance value of the ferromagnetic film according to the film thickness of the ferromagnetic film B, the composition adjustment, the manufacturing conditions, etc., such that Bs is low and the resistance value is high. It is possible to adjust the strength of the coupling bias magnetic field and the so-called shunt bias (operating point bias) generated when a part of the sense current flows through the ferromagnetic film B. It should be noted that the ferromagnetic film is N having an anisotropic magnetoresistive effect.
When it is made of iFe or the like, it is preferable to flow the sense current in the direction orthogonal to the direction of the signal magnetic field. That is, in the method of flowing the sense current in the direction orthogonal to the signal magnetic field, N
When an iFe film or the like is used, the usual anisotropic magnetoresistive effect, which cannot be ignored, and the resistance change due to spin-dependent scattering are superimposed, so that ΔR / R increases.

When a bias magnetic field is applied to a ferromagnetic film by using an antiferromagnetic film, it sometimes becomes a problem that the bias magnetic field is too large. It can be reduced by interposing a laminated film of a ferromagnetic film whose anti-ferromagnetic film side is a ferromagnetic film and a non-magnetic film between the ferromagnetic film and the like.

In the eighth aspect of the invention as described above, the magnetization between adjacent ferromagnetic films sharply changes from the antiparallel state to the parallel state due to the signal magnetic field. Further, the bias magnetic field from the antiferromagnetic film or the like, which is necessary to make the magnetization directions antiparallel to each other when the signal magnetic field of both ferromagnetic films is zero, is suppressed to the minimum necessary to suppress Barkhausen noise. . Therefore, when a signal magnetic field is applied in the difficult axis direction suitable for the magnetic head (there are advantages such as good high frequency characteristics).
However, due to the magnetization rotation of both ferromagnetic films, the magnetization between both ferromagnetic films changes from 0 to 180 ° in a relatively low magnetic field range.
Therefore, a large rate of resistance change similar to that in the easy axis direction is exhibited in a relatively low magnetic field range. In the eighth invention,
The directions of the bias magnetic fields applied to the two ferromagnetic films do not necessarily need to be antiparallel to each other. In other words, when the signal magnetic field is zero, the angle formed between the magnetization directions of both ferromagnetic films and the signal magnetic field direction is It may not be set to + 90 ° and -90 °, respectively. Specifically, when the signal magnetic field is zero, the angles formed by the magnetization directions of both ferromagnetic films and the signal magnetic field are +
It is preferably set within the range of 30 ° to 60 ° and -30 ° to 60 °. The reason is that when the signal magnetic field is zero, the magnetization directions of both ferromagnetic films are inclined so that the angle formed by the signal magnetic field from the antiparallel state is within the range described above, so that the operating point bias becomes unnecessary. Because.

Further, in the conventional spin-valve magnetoresistive effect element, the resistance change rate exponentially increases as the thickness of the nonmagnetic film decreases, so it is desirable to reduce the thickness of the nonmagnetic film as much as possible. However, in reality, when the thickness of the non-magnetic film becomes less than 2 nm, the ferromagnetic coupling between the upper and lower ferromagnetic films becomes strong, the antiferromagnetic magnetization arrangement cannot be realized, and the resistance change rate is significantly reduced. There is a problem. However, in the eighth invention in which a bias magnetic field is applied to both ferromagnetic films, an antiferromagnetic magnetization arrangement can be realized by adjusting the antiparallel bias magnetic field strength even if the thickness of the nonmagnetic film is less than 2 nm. A dramatic increase in resistance change rate can be expected.

Since a bias magnetic field is applied to the two ferromagnetic films, the magnetic domain walls are eliminated from all the ferromagnetic films, and Barkhausen noise can be suppressed.

The magnetoresistive element of the eighth invention is
In addition to the above structure, a nonmagnetic film and a ferromagnetic film may be alternately laminated a plurality of times.

A ninth aspect of the present invention is a magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially laminated on a substrate. The films serve as a magnetically pinned film whose magnetization direction is substantially maintained even when a signal magnetic field is applied, and a magnetic field detection film whose magnetization changes by the signal magnetic field to detect the signal magnetic field. There is provided a magnetoresistive effect element characterized in that the magnetization directions of the two ferromagnetic films are substantially orthogonal to each other and a sense current is passed in the signal magnetic field direction.

In the ninth invention, as a method of fixing the magnetization of the magnetization fixed film, a method of laminating an antiferromagnetic film so as to exchange-couple with the magnetization fixed film, a method of increasing the Hc of the magnetization fixed film, A method of laminating a ferromagnetic film having a high Hc on the magnetization fixed film can be mentioned. Further, as a method of making the magnetization directions of the magnetization pinned film and the magnetic field detection film orthogonal to each other when the signal magnetic field is zero, a method of providing an easy axis of magnetization of the magnetic field detection film so as to be orthogonal to the magnetization of the magnetization pinned film, a magnetic field detection A method of forming a bias film adjacent to or close to the film and applying a weak exchange coupling bias of, for example, about 5 kA / m or less in a direction orthogonal to the magnetization of the magnetization fixed film can be mentioned. According to the latter method, even when the magnetic field detection film is made of CoFe having a particularly large bias magnetic field, the easy axis of magnetization of the magnetic field detection film is imparted in substantially the same direction as the magnetization of the magnetization fixed film,
By giving an exchange coupling bias that slightly exceeds the anisotropic magnetic field of CoFe in the in-plane direction orthogonal to the easy axis of magnetization, the magnetic anisotropy of the magnetic field detection film can be reduced, and as a result, a large resistance change occurs in the low magnetic field range. It is possible to get a rate.

In the ninth invention, the angle formed by the magnetization of the magnetization fixed film and the magnetization of the signal magnetic field detection film is about 90 when the signal magnetic field is zero.
When the angle is set to °, for example, when the magnetization of the magnetization pinned film is oriented in the direction of the positive signal magnetic field, the angle formed by the magnetizations of the adjacent ferromagnetic films becomes ferromagnetic in the positive signal magnetic field. On the contrary, in the negative signal magnetic field, the angle formed by the magnetizations of the adjacent ferromagnetic films becomes antiferromagnetic, and the resistance increases. That is, the operating point bias becomes unnecessary.

Further, when the sense current is passed in the signal magnetic field direction, the magnetization of the magnetic field detection film is inclined by the current magnetic field in the direction orthogonal to the signal magnetic field. Therefore, Barkhausen noise can be suppressed due to the current magnetic field applied to the magnetic field detection film. Further, in this case, since there is a current magnetic field, the easy axis of magnetization is not always required in the magnetic field detection film.

The magnetoresistive effect element of the ninth invention is
In addition to the above structure, a nonmagnetic film and a ferromagnetic film may be alternately laminated a plurality of times.

A tenth aspect of the present invention is a magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a nonmagnetic film, and a ferromagnetic film are sequentially laminated on a substrate. When the signal magnetic field is zero, the film becomes a magnetically pinned film that retains its magnetization direction substantially even when a signal magnetic field is applied, and a magnetic field detection film that detects the signal magnetic field by changing its magnetization direction due to the signal magnetic field. An angle θ formed by the magnetization directions of the two ferromagnetic films in 30 is not less than 30 ° and not more than 60 °.

In the tenth invention, as a method for fixing the magnetization of the magnetization fixed film, a method utilizing an exchange bias generated by laminating an antiferromagnetic film on the magnetization fixed film and the magnetization are the same as in the ninth invention. There is a method of using a high coercive force film as the ferromagnetic film to be the fixed film. Further, as the bias magnetic field applying means to the magnetic field detection film, the easy axis of magnetization of the magnetic field detection film,
The bias magnetic field from the hard magnetic film formed adjacent to or close to the magnetic field detection film, the magnetostatic bias generated from the ferromagnetic film formed adjacent to or close to the antiferromagnetic film, the current magnetic field from the sense current, etc. Available. In order to use the current magnetic field from the sense current, it is necessary to pass the sense current in almost the same direction as the signal magnetic field. However, from the viewpoint of stably pinning the magnetization in the magnetization pinned film, the sense current is applied in the direction orthogonal to the signal magnetic field so that the current magnetic field from the sense current is applied in almost the same direction as the magnetization direction of the magnetization pinned film. It is desirable to do.

In the tenth aspect of the invention, the angle θ formed by the magnetization fixed film and the magnetic field detection film when the signal magnetic field is zero is 30 to 60.
Since the setting is made within °, the Barkhausen noise can be removed by eliminating the operating point bias due to the leakage magnetic field from the magnetization pinned film. The angle θ formed by the magnetization fixed film and the magnetic field detection film as described above in the tenth invention is 30 ° to
The reason for setting 60 ° is that if the angle θ is less than 30 °, the linear response magnetic field range to the signal magnetic field is narrowed, and if it exceeds 60 °, Barkhausen noise removal may not be sufficiently performed.

Here, when the sense current is passed in the direction orthogonal to the signal magnetic field, the direction of the ferromagnetic coupling magnetic field between the two ferromagnetic films and the direction of the current magnetic field are on the same axis. As a result, when a sense current is passed so that the ferromagnetic coupling direction between adjacent ferromagnetic films that cause a decrease in magnetic permeability and the current magnetic field direction are substantially the same, in this case, strong magnetization that is not magnetically fixed is obtained. Since the magnetization direction of the magnetic film rotates in the magnetization direction of the fixed ferromagnetic film, the angle formed by the magnetizations of both ferromagnetic films decreases. As a result, even if a material exhibiting an anisotropic magnetoresistive effect is used as the ferromagnetic film, the anisotropic magnetoresistive effect and the resistance change due to spin-dependent scattering are superposed, and an increase in sensitivity can be expected. On the contrary, if the sense current is made to flow so that the ferromagnetic coupling direction and the current magnetic field direction are opposite to each other, in this case, the angle formed by both ferromagnetic films increases, so that the linear response magnetic field range for the signal magnetic field is increased. Can be expanded. Therefore, it is preferable to appropriately select the conduction direction of the sense current according to the material of the ferromagnetic film.

The magnetoresistive effect element of the tenth aspect of the invention may have a structure in which a nonmagnetic film and a ferromagnetic film are alternately laminated a plurality of times in addition to the above structure.

An eleventh aspect of the present invention is a magnetoresistive effect element comprising a substrate, on which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially laminated. There is provided a magnetoresistive effect element characterized by comprising, as a bias magnetic field applying means to the film, a bias film having two or more layers laminated adjacent to or close to the laminated film.

In the eleventh invention, the bias film may be formed on the uppermost ferromagnetic film of the laminated film and between the lowermost ferromagnetic film and the substrate, or may be formed on the uppermost layer of the laminated film. Two or more layers may be formed on the ferromagnetic film, or two or more layers may be formed between the lowermost ferromagnetic film and the substrate.

In the eleventh invention, the bias film may be an antiferromagnetic film or a ferromagnetic film,
The exchange coupling magnetic field from the antiferromagnetic film, the exchange coupling magnetic field or the magnetostatic coupling magnetic field from the ferromagnetic film, and the current magnetic field from the sense current are applied to the ferromagnetic film in the laminated film as a bias magnetic field. To be done. Here, in the case of generating an exchange coupling magnetic field from the ferromagnetic film as the bias film,
Even if a film for reducing the exchange bias is arranged between the ferromagnetic film of the laminated film and the ferromagnetic film of the bias film, the ferromagnetic film of the bias film is directly formed on the ferromagnetic film of the laminated film. May be. However, in the former case, the uniaxial anisotropic magnetic field Hk of the bias film is equal to the uniaxial anisotropic magnetic field Hk of the ferromagnetic film of the laminated film.
is preferably larger than k, and the coercive force H of the bias film is
It is preferable that c is larger than the coercive force Hc of the ferromagnetic film of the laminated film.

In the eleventh aspect of the invention, a bias magnetic field whose magnetization does not substantially move with a signal magnetic field is applied to either the uppermost layer or the lowermost ferromagnetic film to form a fixed magnetization film, and the other is to be a fixed magnetization film. It is preferable to add a bias magnetic field that can detect a signal magnetic field and remove Barkhausen noise to form the magnetic field detection film. At this time, a stack of antiferromagnetic films is suitable for applying a bias magnetic field to the magnetization fixed film. Further, a stack of ferromagnetic films or antiferromagnetic films is suitable for applying a bias magnetic field to the magnetic field detecting film. Here, the ferromagnetic film as the bias film has a high resistance soft magnetic property in which the magnetic domain is made into a single magnetic domain by some method such as a Co-based amorphous film which is heat-treated in a rotating magnetic field and the magnetization directions are aligned in one direction. Film or C heat treated in a static magnetic field
A film having a high uniaxial magnetic anisotropy such as an o- or CoFe-based amorphous film, or a high coercive force film is suitable. In addition, the ferromagnetic film that becomes the bias film is formed wider than other films,
Even if a hard magnetic film or an antiferromagnetic film is laminated on the edge portion, a high resistance soft magnetic film having a single magnetic domain can be realized.

In the eleventh invention, at least two layers of bias films are further laminated adjacent to or close to the above-mentioned laminated film so that magnetization can be fixed to a specific ferromagnetic film. It is possible to apply a strong bias magnetic field to the other specific ferromagnetic film with the minimum required bias magnetic field for removing Barkhausen noise. At this time, in the eleventh invention in which two or more bias films are laminated, compared to a case where only the magnetic field detection film is formed wider than other magnetization pinned films and the bias film is laminated at the edge portion, There is an advantage that a multilayer film including a bias film can be easily manufactured in a short time by batch continuous film formation. This is because it is very difficult to remove only the edge portions of the magnetic field detection film having a thickness of about 1 to 20 nm and remove the edge portions of other magnetization pinned films to form only the magnetic field detection film widely. based on.

Further, if the bias magnetic fields applied to the ferromagnetic film by the two bias films are made orthogonal to each other,
In the same manner as the above invention, the angle formed by the magnetization directions of the magnetization fixed film and the magnetic field detection film when the signal magnetic field is zero becomes approximately 90 °, and the operating point bias becomes unnecessary. In addition, Barkhausen noise can be removed by the bias magnetic field applied to the magnetic field detection film.
In addition, the magnitude of the bias magnetic field can be easily controlled by adjusting the magnetic anisotropy and film thickness of the bias film or the interface between the laminated film and the bias film. Moreover, by applying a bias magnetic field in a direction substantially orthogonal to the direction of the easy axis of magnetization of the ferromagnetic film, it is possible to improve the magnetic permeability of the ferromagnetic film made of a Co-based material exhibiting a high Hk.

The eleventh aspect of the present invention comprises, on a substrate, a laminated film in which three layers of ferromagnetic films and two layers of non-magnetic films are alternately formed, and the uppermost and lowermost ferromagnetic films are formed. It can be preferably applied also to a magnetoresistive effect element in which a central ferromagnetic film having a high magnetic permeability serves as a magnetically pinned film and serves as a magnetic field detecting film.

In such a magnetoresistive effect element, the uppermost ferromagnetic film and the lowermost ferromagnetic film have a low magnetic permeability, that is, two or more bias layers formed adjacent to or close to the laminated film. Since the magnetization is fixed in the film, the change in the magnetization direction with respect to the signal magnetic field is slight. On the other hand, since the central ferromagnetic film has a high magnetic permeability, a large magnetic field is generated by a slight magnetic field. As a result, the angle formed by the magnetization of the uppermost ferromagnetic film and the lowermost ferromagnetic film and the magnetization of the central ferromagnetic film sharply changes due to the signal magnetic field. In addition, the number of interfaces causing spin-dependent scattering is at least doubled as compared with the conventional spin valve structure film. Therefore, a large change in resistance can be obtained with a slight magnetic field.

When the magnetization of the central ferromagnetic film is fixed by a bias film such as an antiferromagnetic film to reduce the magnetic permeability,
Since the antiferromagnetic film has a high resistivity, ΔR / R is significantly reduced, but if the magnetizations of the uppermost and lowermost ferromagnetic films are fixed, the antiferromagnetic film should be placed outside the spin-dependent scattering unit. Therefore, the magnetization can be fixed without reducing ΔR / R.

Further, since the ferromagnetic film having a high magnetic permeability exists in the vicinity of the center of the laminated film having the spin valve structure, the current magnetic field from the sense current is weakened, and as a result, the magnetic field detecting film becomes strong due to the current magnetic field. It is possible to avoid the problem that the magnetization arrangement of the magnetic film is disturbed.

A twelfth aspect of the invention is characterized in that a high coercive force film having a hexagonal C-axis in the film plane and a ferromagnetic film having a coercive force lower than that of the high coercive force film are provided on a substrate. To provide a magnetoresistive effect element.

In the twelfth aspect of the invention, it is possible to prevent the ordinary high coercive force film from having a high coercive force due to strong magnetostatic coupling due to crystal magnetic anisotropy in the direction perpendicular to the film surface. As a result, when this high coercive force film is used as the magnetization fixed film in the film of the spin valve structure, the soft magnetic characteristics of the magnetic field detection film for detecting the signal magnetic field are not deteriorated. In addition, the parallel and anti-parallel states of magnetization can be efficiently realized,
Furthermore, since the non-magnetic film thickness in the laminated film can be significantly reduced, the rate of resistance change can be increased. In addition,
Here, the high coercive force film and the non-magnetic film as the magnetization fixed film may be alternately laminated a plurality of times.

Furthermore, since the single crystal-like high coercive force film has a low electric resistance, even when it is formed as a laminated film with a low coercive force film, the output can be increased without affecting the spin-dependent scattering. Furthermore, since this single crystal-like high coercive force film has high crystal magnetic anisotropy, it has high magnetic permeability (magnetization is hard to move).
Has a large effect of fixing the magnetization.

Further, in the twelfth invention, the high coercive force film may be used as a bias film for applying a bias magnetic field to the ferromagnetic film. At this time, for example, even when the high coercive force film is used as the bias film for fixing the magnetization of the magnetization fixed film, the soft magnetic characteristics of the magnetic field detection film for detecting the signal magnetic field are not deteriorated. In addition, this high coercive force film can be used as a bias film for Barkhausen noise countermeasures and as a bias film that creates an anti-coupling state of the magnetization when there is no signal magnetic field, and it is also possible to have both functions at the same time. Is. Further, the twelfth invention is not limited to a magnetoresistive effect element having a laminated film in which a ferromagnetic film and a non-magnetic film are alternately formed on a substrate, and an anisotropic magnetoresistive effect such as NiFe alloy is used. It can also be applied to a magnetoresistive effect element.

[0103]

EXAMPLES Examples of the present invention will be specifically described below. (Example 1) As a substrate, a sapphire substrate C surface (α-Al ₂ O ₃ substrate (0) was used with a stylus type surface roughness meter having a stylus tip radius of 0.2 μm until the average surface roughness was about 2 nm.
The (001) surface) was polished to a mirror surface state by the mechanochemical polishing method.

This sapphire substrate was placed in a vacuum chamber and the vacuum chamber was evacuated to 5 × 10 ⁻⁷ Torr or less. Then, Ar gas was introduced into the vacuum chamber, and the inside of the vacuum chamber was set to about 3 mTorr, and about 4000
By performing sputtering in a static magnetic field of A / m, as shown in FIG. 1, a Co ₉₀ Fe ₁₀ film 11 which is a ferromagnetic film and a C which is an intermediate non-magnetic film are formed on the sapphire substrate 10.
A u film 12, a Co ₉₀ Fe ₁₀ film 11 as a ferromagnetic film, an FeMn film 13 as an antiferromagnetic film, and a Ti film 14 as a protective film are sequentially formed to form Ti 5 nm / FeMn 8 nm / Co ₉₀ Fe ₁₀ 8
A laminated film having a spin valve structure of nm / Cu 2.2 nm / Co ₉₀ Fe ₁₀ 8 nm was prepared to obtain a magnetoresistive effect element. Further, a Cu lead 15 was formed on this laminated film. In addition,
The composition of the CoFe-based alloy film was set to Co ₉₀ Fe ₁₀ from the viewpoint of showing a large rate of resistance change [Journal of Applied Magnetics of Japan, 16 , 313 (1992)] and soft magnetic properties.

Here, as the material of the protective film, other than Ti, a non-magnetic material such as Cu, Cr, W, SiN, or TiN can be used. In addition, in order to prevent the oxidation of FeMn, it is desirable to use a material other than an oxide. Further, the film thickness of the Ti film 14 need not be 5 nm as long as it has a protective effect.
The film thickness is several tens of nm or less in order to prevent the sensitivity from being lowered due to the shunting to the Ti film 14 when the sense current is passed, and in consideration of having a higher electric resistivity than the Co ₉₀ Fe ₁₀ film 11. Is desirable.

Co ₉₀ Fe ₁₀ film 1 in contact with the FeMn film 13
1 is magnetically fixed by FeMn and the other Co ₉₀
The Fe ₁₀ film 11 is magnetized / reversed and rotated according to an external magnetic field. The thickness of the Co ₉₀ Fe ₁₀ film 11 which is a ferromagnetic film is 8 nm in both layers, but the thickness of the two ferromagnetic films may be the same or different. A ferromagnetic film can be used in principle if its thickness is one atomic layer (0.2 nm) or more,
For practical use of the MR element, 0.5 to 20 nm is appropriate.

The Cu film 12 formed between the two Co ₉₀ Fe ₁₀ films 11 has a film thickness of 2.2 nm in this embodiment, but it may have a film thickness other than this, and is practically 0.5 to 20 nm. Is desirable. Further, as materials other than Cu, Au, Ag,
Ru, Cu alloy, etc. can be used.

The FeMn film 13, which is an antiferromagnetic film, is used for fixing the magnetization of the Co ₉₀ Fe ₁₀ film 11 in direct contact with it. This film thickness can be used if it is about 1 nm or more, but it is preferably 2 nm to 50 nm for reliability and practicality.
In addition to FeMn, Ni oxide can be used as a material for the antiferromagnetic film. When Ni oxide is used as the material of the antiferromagnetic film, good Ni oxide can be obtained by performing sputtering in a mixed gas atmosphere of Ar and oxygen, or applying an ion beam sputtering method, a dual ion beam sputtering method, or the like. An antiferromagnetic film can be formed. In addition, since the Ni oxide film can be favorably formed on the C surface of the sapphire substrate, the spin valve structure is Ti 5 nm.
/ Co ₉₀ Fe ₁₀ 8 nm / Cu 2.2 nm / Co ₉₀ Fe ₁₀ 8 nm
/ Ni oxide may be 50 nm. In this case, N
When the thickness of the i oxide film is 1 nm or more, a stable bias magnetic field can be applied to the Co ₉₀ Fe ₁₀ film.

The magnetic characteristics, the rate of resistance change, and the crystal structure of the magnetoresistive effect element were examined. The magnetic characteristics were measured with a vibrating magnetometer (VSM) at a maximum applied magnetic field of 1.2 MA / m, and the resistance change rate was measured by a four-terminal resistance measuring method in a static magnetic field. The crystal structure was measured by a θ-2θ scan and a rocking curve X-ray diffraction method. In VSM and X-ray diffraction, the resistance change rate was measured for a film patterned in a square of 8 mm with a metal mask, and for the film patterned in a 1 mm × 8 mm stripe pattern by a metal mask. The resistance change of the magnetoresistive element in the magnetic field was measured by the four-terminal method.

The measurement results of the magnetoresistive effect element are shown in FIG. As can be seen from FIG. 2, when the external magnetic field was applied in the direction of the easy axis of magnetization, the maximum resistance change rate was about 10%. The coercive force of this magnetoresistive effect element was 160 A / m or less. As described above, this magnetoresistive effect element has about 1
With a weak magnetic field of 60 A / m, a large resistance change of about 10% was obtained, and it was found that good soft magnetic characteristics and a high resistance change rate were obtained. When an external magnetic field was applied in the direction of the hard axis, the resistance change rate was about 4%, but the coercive force was 80 A / m, which was an extremely good soft magnetic property.

Magnetization curves of this magnetoresistive effect element are shown in FIGS. 3 (A) and 3 (B). As can be seen from FIG. 3 (A), the coercive force in the easy axis direction is about 160 A /
m, the coercive force in the hard axis direction is about 80 A / m. Further, as can be seen from FIG. 3B, it is found that an exchange bias of about 5.3 KA / m is applied to the Co ₉₀ Fe ₁₀ film in contact with FeMn in the direction of the easy axis of magnetization.

Further, the crystal structure of this magnetoresistive effect element showed strong fcc phase (111) plane orientation (closest plane orientation).

Ti is formed on the thermally oxidized Si substrate in the same manner as above.
A / FeMn / CoFe / Cu / CoFe film was formed.
As a result of evaluation in the same manner as above, the close-packed surface peak of X-ray diffraction was reduced to 1/10 or less as compared with the above case, Hc was 3000 A / m in the easy axis direction, and the magnetoresistive effect element was obtained. It is a high value that is difficult to apply to, and the rate of resistance change is 8% or less, which is smaller than that of the above (111) oriented film.

Next, a Ti / FeMn / CoFe / Cu / CoFe film was formed on the MgO (100) substrate in the same manner as above. As a result of evaluation in the same manner as above, only X-ray diffraction peaks of high intensity (100) peak were obtained.
That is, it showed a good (100) orientation. At this time, H
c was 1200 A / m in the easy axis direction, and showed a high value that was difficult to apply to a magnetoresistive effect element, and the resistance change rate was 8% or less, which is smaller than that of the above (111) oriented film.

From the above, it can be seen that when the (111) orientation is realized, low Hc and high resistance change rate can be realized.

Next, Ti using a Co film as a ferromagnetic film was used.
5nm / FeMn8nm / Co8nm / Cu2.2nm / Co8
A magnetoresistive element having a spin valve structure of nm was produced on a sapphire C-plane substrate, and the magnetic characteristics and the resistance change rate were measured in the same manner as above. The similar close-packed plane orientation and the resistance change rate were about 8%. Value, the coercive force is 800 A / m
There was a degree. In the case of a thermally oxidized Si substrate, ΔR / R = 7
%, Hc = 2000 A / m.

From these results, C was selected as the material for the ferromagnetic film.
Even if o is used, low Hc and high ΔR / R can be obtained, but it is more preferable to use an alloy in which Fe is added to Co as a material of the ferromagnetic film because soft magnetic characteristics are likely to occur.

Furthermore, Ti5nm / FeMn8nm / Co
_{100-x Fe x 8nm / Cu2.2nm} / Co 100-x Fe x 8
A spin valve type magnetoresistive effect element composed of nm / sapphire C plane or a glass substrate was manufactured by changing the Fe concentration x (atomic%) of the Co _100-x Fe _x ferromagnetic film. The relationship between ΔR / R and Hc obtained as a result is shown in Table 1 below. As can be seen from Table 1, 5 ≦ x ≦ 4 on the sapphire C surface
It is clear that a significant Hc reduction and ΔR / R increase are realized in the 0 range.

[0119]

[Table 1] (Example 2) On a C surface of a sapphire substrate, on a glass substrate (# 0211 manufactured by Corning Incorporated), and on a (111) surface of a Si substrate, a Cu base film having a thickness of 10 nm was formed, and further implemented thereon. A Co ₉₀ Fe ₁₀ film was formed under the same film forming conditions as in Example 1. The Cu base film can be formed by a bias sputtering method, an ion-assisted ion beam sputtering method, a vapor deposition method, or the like. The coercive force (Hc) of this Co ₉₀ Fe ₁₀ film was measured. Further, the Co ₉₀ Fe ₁₀ film was formed on each of the substrates with a Cu underlayer film having various thicknesses, and the coercive force (Hc) of the Co ₉₀ Fe ₁₀ film was measured. The result is shown in FIG. Further, Co ₉₀ Fe ₁₀ films of various thicknesses were formed in the same manner as above without forming a Cu base film on the substrate, and the coercive force (H
c) was measured. The result is shown in FIG. 7.

As can be seen from FIGS. 6 and 7, in any of the substrates, the Hc is lower when the Cu underlayer is formed (FIG. 6) than when there is no Cu underlayer. Further, it can be seen that regardless of the presence or absence of the Cu underlayer, the C plane of the sapphire substrate, the (111) plane of the Si substrate, and the glass substrate have low Hc in this order, which is good. In particular,
When a Co ₉₀ Fe ₁₀ film having a thickness of 8 nm was formed on the C surface of the sapphire substrate via a Cu underlayer, a low Hc of 80 A / m or less was exhibited. It should be noted that Co ₉₀ Fe ₁₀ having a Cu base film
The Hc of the film tended to slightly increase as the film thickness of the Co ₉₀ Fe ₁₀ film increased. On the other hand, C without Cu underlayer
The Hc of the o ₉₀ Fe ₁₀ film first showed a tendency to decrease as the film thickness increased, and then to increase as the film thickness increased. For example, when the film thickness of the Co ₉₀ Fe ₁₀ film was about 8 nm, the minimum value of Hc was 160 A / m or less.

As described above, it is understood that excellent soft magnetic characteristics can be obtained by forming the underlayer film between the ferromagnetic films when they are formed on the substrate.

On the C plane of the sapphire substrate or Si
It was found that excellent soft magnetic characteristics can be obtained by using a CuNi alloy film as a base film when forming a Co ₉₀ Fe ₁₀ film or a Co film on a substrate. In addition, as a base film for forming a Co ₉₀ Fe ₁₀ film or a Co film on a glass substrate or a ceramic substrate, Ge, S of several to 100 nm is used.
It was found that by using the i or Ti film, the close-packed plane orientation is promoted, and as a result, good soft magnetic characteristics can be obtained.

By using a material having a higher resistance than the Co ₉₀ Fe ₁₀ film or the Co film for the base film, it is possible to prevent the shunt of the MR sense current. For example, the Ni oxide film described in Example 1 has a high resistance and is an antiferromagnetic film that can be epitaxially grown on the C-plane of a sapphire substrate, and therefore serves as an underlying film and an antiferromagnetic bias film. You can FIG. 8 shows a magnetoresistive effect element having a spin valve structure using the Ni oxide film 26. Example 3 The effect of the plane orientation of the sapphire substrate on the coercive force of the Co ₉₀ Fe ₁₀ film was examined. In this embodiment, C
Plane and R plane ((1012) plane of α-Al ₂ O ₃ substrate)
Compared with.

A Co ₉₀ Fe ₁₀ film having a film thickness of 10 nm was formed on each of the C surface and the R surface of the sapphire substrate. The difference in crystal orientation due to this plane orientation is shown in FIGS. 9 (A) and 9 (B). As can be seen from FIG. 9 (A), good fcc (111) orientation can be realized on the C-plane, resulting in a coercive force of 1
A CoFe alloy film having a good soft magnetic property of 60 A / m or less could be formed. On the other hand, as can be seen from FIG. 9B, in addition to the peak of fcc (111), f
The peak of cc (200) was detected and fcc (111)
The orientation is not very good. Therefore, the coercive force is several hundred A /
Since it was more than m, good soft magnetic characteristics could not be obtained.

In FIG. 9 (A), fc was observed near 2θ = 43.5 ° in the C plane, except for the peak of sapphire which is the substrate.
Only peaks corresponding to the c-phase (111) plane (some hcp
The phase (which may include the (001) plane orientation) appears strongly. The higher the peak intensity, the lower the coercive force of the Co ₉₀ Fe ₁₀ film. On the other hand, in FIG. 9B, in addition to the sapphire peak and the fcc phase (111) plane peak, a peak corresponding to the fcc phase (200) plane appears near 2θ = 52.6 ° in the R plane. The existence of this fcc phase (100) plane orientation means that the magnetocrystalline anisotropy easy axis appears in the plane, which causes a rise in coercive force.

Next, a rocking curve was measured for the peak corresponding to the (111) plane (closest plane) of the Co ₉₀ Fe ₁₀ film on the C plane of this sapphire substrate. The rocking curve is shown in FIG. As can be seen from FIG. 10, an extremely strong orientation with a half-value width of about 3 ° with a peak near θ = 21.8 ° can be confirmed. Although the peak of the sapphire substrate overlaps with this rocking curve,
A good crystal orientation of the Co ₉₀ Fe ₁₀ film can be confirmed.

[0127] Next, FIG. 11 shows the coercive force of the Co ₉₀ Fe ₁₀ film, the correlation between the half width of the rocking curve of the peak corresponding to Co ₉₀ Fe ₁₀ film (111) plane (close-packed plane) . As shown in FIG. 11, Co _{90 is formed} on the glass substrate.
When the Fe ₁₀ film was formed, the (111) peak was often weak, the half-width of rocking curve was 20 ° or more, and Hc was 3000 A / m or more. Further, when the Ar pressure and the substrate temperature are optimized and the half-width of the rocking curve becomes about 15 °, Hc decreases to about 1000 A / m. When a film made of a material obtained by adding about 1% of Al to Co ₉₀ Fe ₁₀ is formed on a glass substrate, the full width at half maximum is 8 °.
Hc is reduced to about 350 A / m. Also,
By forming a Co ₉₀ Fe ₁₀ film on the C-plane of the sapphire substrate, the full width at half maximum is further reduced to about 3 °, and Hc
Is about 160 A / m. Therefore, the closest surface (C
In the case of the o ₉₀ Fe ₁₀ film, it can be confirmed that the coercive force tends to sharply decrease as the half-width of the rocking curve of the peak corresponding to the (111) plane decreases to less than 20 °. For example, if the full width at half maximum of the rocking curve is 7 ° or less,
It can be seen that the coercive force approaches a good value of 160 A / m. That is, according to the close-packed plane orientation of the Co ₉₀ Fe ₁₀ film is getting stronger, the coercive force of the Co ₉₀ Fe ₁₀ film is reduced. Thus, it can be seen that good soft magnetic properties are strongly correlated with the degree of orientation of the ferromagnetic film.

As a method of strengthening the close-packed plane orientation of the Co ₉₀ Fe ₁₀ film, as described above, firstly, a method of adding various additive elements described later, secondly, a method of selecting a substrate material / orientation, and secondly There are several methods such as a method of forming an underlayer film between the substrate and the Co ₉₀ Fe ₁₀ film in 3 and a method of forming a film by an ultra-high vacuum film forming apparatus such as MBE. In the second method, when the C surface of the sapphire substrate is used as the substrate, the surface is polished by mechanochemical polishing, float polishing or ion polishing to reduce the average surface roughness (Ra) of the substrate to 2 nm or less. By doing so, it was found that the Co ₉₀ Fe ₁₀ film formed thereon exhibited even better soft magnetic characteristics. However, when the average surface roughness was 5 nm or more, the Co ₉₀ Fe ₁₀ film had a coercive force of 1000 A / m or more. (Example 4) In Example 3, it was found that the coercive force of the single-layer Co ₉₀ Fe ₁₀ film was lowered by increasing the close-packed plane orientation by the first and second methods. Next, it is confirmed whether the same can be said for the laminated film including the Co ₉₀ Fe ₁₀ film.

Al-containing Co ₉₀ Fe ₁₀ 10 on a glass substrate
A laminated film of nm / Cu 5 nm / Al-containing Co ₉₀ Fe ₁₀ 10 nm was formed under the same film forming conditions as in Example 1. Co in this case
The relationship between the ₉₀ Fe ₁₀ Al element addition amount in the film and the Co ₉₀ Fe ₁₀ film coercivity is shown in Figure 12. As can be seen from FIG.
It can be seen that the coercive force can be reduced also in the laminated film by adding the Al element. In addition, the Co ₉₀ in the laminated film is similarly formed by the second to fourth methods shown in the second embodiment.
The orientation of the close-packed surface of the Fe ₁₀ film could be strengthened.

Next, FIG. 13 shows the close-packed surface peak intensity dependence of the coercive force of the Co ₉₀ Fe ₁₀ film in the laminated film. FIG.
As can be seen from the above, it can be confirmed that the coercive force is decreased as the peak density of the close-packed surface is increased similarly to the case of the single layer film. In the case of the above structure, the peak strength is as weak as 10 ² (au) and the coercive force is about 10 ³ A / m. In this case, the coercive force was reduced to about several hundred A / m by using a film made of a material in which Al was added to Co ₉₀ Fe ₁₀ at about 1 atom%. Further, by replacing the glass substrate with the C surface of the sapphire substrate, a peak intensity of 10 ³ (au) or more and a good coercive force of 100 A / m or less were obtained. The full width at half maximum at this time was 7 ° or less. Example 5 The coercive force was examined by adding an additive element other than Al to Co ₉₀ Fe ₁₀ . In this case, as the additive element, Ta,
Pd, Zr, Hf, Mo, Ti, Nb, Cu, Rh, R
A decrease in coercive force was also observed when using e, In, B, Ru, Ir, and W. Further, it was confirmed that the coercive force was lowered even when a combination of those elements, for example, Ta and Pd, Nb and Pd, and Zr and Nb were added. As an example, Ta-containing Co ₉₀ Fe ₁₀ 10 nm / Cu ₅ nm / Ta-containing Co ₉₀ Fe
FIG. 14 shows the relationship between the added amount of Ta and the coercive force in the structure of the laminated film of ₁₀ 10 nm. As can be seen from FIG.
Also in this case, it can be confirmed that the coercive force was lowered by the addition of the Ta element. (Example 6) The above is an example in which a (111) high orientation is realized for a CoFe film, but the CoFe film is not limited to the CoFe film,
The same effect was observed when using a CoFeNi film, a CoNi film, or the like. Examples thereof are shown in Table 2 below. Table 2 shows
(1) Composition of ferromagnetic film, (2) type of substrate, (3) structure similar to that shown in FIG. 1 prepared by using a base film between the substrate and the spin valve film as a parameter (the side in contact with the FeMn film is Co.
FIG. 9 shows the rocking curve half width Δθ ₅₀ of the (111) peak, Hc in the easy axis direction, and ΔR / R in the spin valve film having the Fe film). For comparison, Table 2 also shows the results when a spin valve film of a ferromagnetic film having the same composition as in Table 2 was formed on a glass substrate without an underlying film.

[0131]

[Table 2] As can be seen from Table 2, not only CoFe film but also CoFeN
Compared to the direct film formation on the glass substrate, the i film and the CoNi film have better Δθ ₅₀ <7 ° by using the sapphire C-plane substrate or the base film made of Ti, Si, Ge or the like. ) An alignment film can be obtained, and as a result, Hc
Can be reduced, and a high resistance change rate can be realized.

However, the (111) highly oriented (M 1 nm thickness / Cu
When a _16- nm artificial lattice film was prepared (M: Co ₂₀ N)
i ₈₀ , Co ₂₀ Fe ₁₅ Ni ₆₅ ), ΔR / R showed a remarkably small value of 2% or less, and the high saturation magnetic field peculiar to RKKY antiferromagnetic coupling disappeared. It can be seen that when the (111) orientation is obtained, the RKKY-like antiferromagnetic coupling cannot be obtained, so that the resistance change rate is lowered. Therefore, it is not limited to spin-valve films, but also types that do not use RKKY-like antiferromagnetic coupling (so-called non-coupling artificial lattice films that use the difference in coercive force (Proceedings of the 14th Annual Meeting of the Japan Society for Applied Magnetics, 1990, (177) etc.), it is easy to achieve both a high rate of resistance change and good soft magnetism.

In addition to this, it was confirmed that the same effect can be obtained by replacing the ferromagnetic film in contact with FeMn with a film having the same composition as the lower magnetic film. (Example 7) Ti 5 nm / on a glass substrate (without a base film)
A spin valve film of FeMn 8 nm / CoFe 8 nm / Cu 2.2 nm / ferromagnetic film 8 nm was formed under the same conditions as in Example 1. Table 3 below shows the relationship between the non-magnetic additive element added to the lower ferromagnetic film, the rate of change in resistance in the easy axis direction, and Hc.

[0134]

[Table 3] As can be seen from Table 3, Hc was lower than that of the film formed on the glass substrate and containing no nonmagnetic element. Al, Ta
When Hc is added, the decrease in Hc is remarkable, but when added in a large amount, the resistance change rate is significantly decreased. Al is less than 6.5 at%, Ta is less than 10 at%, and the resistance change rate is 5% or more and the low Hc is higher than that of the spin valve film made of NiFe.
It turns out that both can be achieved. When Al or Ta was added to CoFe, the peak density of the close-packed plane in X-ray diffraction increased. On the other hand, Cu, Au, Ag, Pd, etc. are H
The effect of reducing c is not as remarkable as that of Al or Ta, but 10
No decrease in resistance change rate is observed even when a large amount of atomic% or less is added. The addition of Cu, Au, Ag, Pd, etc. to CoFe also increased the close-packed surface peak intensity in X-ray diffraction. It is considered that the decrease in Hc is attributed to the above-mentioned improvement in crystal orientation because the peak density of the close-packed plane in X-ray diffraction was improved by the added element. In addition to this,
The decrease in crystal magnetic anisotropy due to the additional element may also be due to the decrease in Hc.

Furthermore, the corrosion resistance of each single-layer ferromagnetic film (thickness: 100 nm) was examined by leaving it in a constant temperature and humidity bath at 65 ° C. and 95% RH for 100 hours. However, the CoFe film containing no non-magnetic element, the Co ₂₀ Ni ₈₀ film, the Co ₂₀ Fe ₁₅ Ni ₆₅ film, the film containing 6.5 atomic% of Al, and the film containing 6 atomic% of Ta are discolored. It was observed. That is, the addition of Pd exerts the effect of improving the corrosion resistance. H when adding only Pd
Although the decrease of c is not so remarkable, when Pd is added together with Cu, for example, it is possible to maintain a high resistance change rate and corrosion resistance and further improve the soft magnetic characteristics. Furthermore, when a sapphire C-plane substrate, an amorphous metal base film, or a base film of fcc lattice is used, Hc is 80 A / m even when only Pd is added.
Pd up to 40 at% of Pd
A high resistance change rate of 10% was shown in the concentration range. However, when Pt, which is expected to be effective in improving corrosion resistance with the same precious metal, was added, Hc increased more than that of the film without Pt added. Therefore, addition of Pt is not preferable from the viewpoint of soft magnetic characteristics. (Example 8) After the surface of a thermally oxidized Si substrate having _a surface roughness _Ra = 2 nm or less was cleaned by SH (mixed solution of sulfuric acid and hydrogen peroxide) treatment, this substrate was placed in a vacuum device. 1x
The gas was evacuated to below 10 ^-9 Torr. Water and oxygen in the vacuum apparatus were controlled by a mass spectrometer and dew point meter. After the above procedure was completed, ultra-high-purity Ar gas was introduced into the apparatus to make the degree of vacuum in the apparatus 1 × 10 ⁻⁴ Torr and generate a microwave discharge of 2.45 GHz inside the ECR ion source. Then, sputtering was performed by an accelerated ion beam, and as shown in FIG. 15, an amorphous Si film having a film thickness of 5 nm was formed as a first base film 151 on the thermally oxidized Si substrate 150. After that, Cu--N is continuously formed on the first base film 151 as a second base film 152 while maintaining a vacuum.
The i alloy was formed into a film having a thickness of 2 nm.

C is formed on the surface as the first ferromagnetic film 153.
The o ₉₀ Fe ₁₀ alloy film has a thickness of 8 nm, and the non-magnetic film 154 is a Cu—Ni alloy film having a thickness of 2.2 nm.
A Co ₉₀ Fe ₁₀ alloy film having a thickness of 8 nm is formed as 55, an Fe—Mn alloy film is formed as an antiferromagnetic film 156 having a thickness of 8 nm, and a Ti film is formed as a protective film 157 having a thickness of 5 nm. A laminated film of All of the above thin films were formed by ion beam sputtering. Further, by forming Cu electrodes 158a and 158b on this laminated film, a spin valve type magnetoresistive effect element 159 was obtained.

C in the ferromagnetic films 153 and 155
The composition of the oFe-based alloy film was Co ₉₀ Fe ₁₀ from the viewpoint of a large rate of change in resistance (Journal of Japan Applied Magnetics: 16.313 (1992)) and soft magnetic properties.

The spin valve magnetoresistive element thus obtained was measured for crystallinity, magnetic characteristics and resistance change rate. The coercive force, which is one of the physical properties indicating the above, was 0.1 Oe. Further, the magnetoresistance change rate measured using this element showed a high value of about 10%.

For comparison, a substrate subjected to the same treatment was placed in a vacuum apparatus, exhausted to 1 × 10 ⁻⁷ Torr or less, and then ordinary Ar gas was introduced to 2 × 10 ⁻³ Torr. A Cu film was directly formed as a base film without forming an amorphous Si film on the surface of the substrate, and a laminated film having the same spin valve structure as that of Example 8 was formed on the surface. further,
A Cu electrode was formed on this laminated film to obtain a magnetoresistive effect element. This laminated film was formed by the usual two-pole sputtering method excited at 13.56 MHz.

When the crystallinity, magnetic characteristics and resistance change rate of this magnetoresistive effect element were measured, the full width at half maximum by X-ray diffraction of the CoFe alloy film was 7 °, which is one of the physical properties exhibiting soft magnetic characteristics. The coercive force was 1.5 Oe. Also,
The rate of change in magnetoresistance measured using this element was about 5%. Example 9 After cleaning the surface of a sapphire substrate having _a surface roughness R _a = 2 nm or less, the substrate was placed in a vacuum apparatus and evacuated to 1 × 10 ⁻⁹ Torr or less. Water and oxygen in the vacuum apparatus were controlled by a mass spectrometer and dew point meter. After the above procedure was completed, an amorphous CuTi film having a film thickness of 3 nm was formed as a first base film by an ultrahigh vacuum evaporation method using an electron beam evaporation source. After that, continuously maintaining the vacuum, ultrahigh vacuum R with excitation frequency of 100MHz
FeM is used as the second base film by F sputtering.
An n alloy film was formed with a film thickness of 2 nm.

Next, on the above base film, Ti5 nm / FeM
n8nm / (Co ₈₁ Fe ₉ ) Pd ₁₀ 8nm / Cu 2.2nm /
A laminated film having a spin valve structure having a structure of (Co ₈₁ Fe ₉ ) Pd ₁₀ 8 nm was formed by ultra-high vacuum RF sputtering with an excitation frequency of 100 MHz, and a Cu electrode was formed on the laminated film to form a spin film. A bulb type magnetoresistive effect element was produced.

The crystallinity, magnetic characteristics and resistance change rate of the spin valve type magnetoresistive element thus obtained were measured in the same manner as in Example 8. The half width of the CoFe film by X-ray diffraction was 1.5. The coercive force, which is one of the physical properties exhibiting soft magnetic characteristics, was 1 Oe. The rate of change in magnetoresistance measured using the same element was a high value of about 12%. (Embodiment 10) As shown in FIG. 16, a high resistance amorphous layer 31 made of CoZrNb or the like is formed on a supporting substrate 30,
A ferromagnetic film 32 made of a CoFe alloy or the like, a non-magnetic film 33 made of Cu or the like, a ferromagnetic film 32, and FeMn are formed thereon.
An exchange bias layer 34 made of, for example, was sequentially formed in a static magnetic field of about 4 kA / m, and leads 35 were formed on the exchange bias layer 34 to manufacture a magnetoresistive effect element. Each layer is 4
A film was formed using the original sputtering apparatus under the film forming conditions shown in Table 4 below.

[0143]

[Table 4] The magnetic characteristics of this magnetoresistive effect element were investigated, and the MH curve (magnetization-magnetic field curve) thereof is shown in FIGS. 17 and 18. Note that FIG. 17 shows the MH curve in the easy axis direction, and FIG.
Indicates the MH curve in the hard axis direction.

As can be seen from FIG. 17, the coercive force Hc (a in the figure) of the CoFe film on the side not fixed to FeMn is about 500 A / m, which is higher than that of a normal CoFe single layer film of about 1600 A / m. The value was extremely low. Further, also in the hard axis direction on the signal magnetic field input side, as can be seen from FIG. 18, CoF on the side not fixed to FeMn
The coercive force Hc of the e film (b in the figure) is about 600 A / m,
The value was remarkably lower than the Hc of about 1600 A / m of a normal CoFe single layer film.

The resistance change characteristic of this magnetoresistive effect element was examined, and its RH curve (resistance-magnetic field curve) is shown in FIG. As can be seen from FIG. 19, the resistance change rate ΔR
/ R has a high resistance change rate of about 9%, which is similar to that of the conventional Co-based spin valve film. The coercive force Hc (c in the figure) of the CoFe film on the side not fixed to FeMn is shown in FIG.
As expected from the above, the value was as low as about 500 A / m.

In this embodiment, Fe is used as the exchange bias layer.
Although the Mn film is used, it is confirmed that an antiferromagnetic film such as NiO may be used, and that an artificial lattice film having a structure such as (Co / Cu) n may be used to obtain good characteristics. Was done. Further, in the present embodiment, the CoZrNb film is used as the high resistance amorphous layer, but in addition to this, fine crystal FeZr film, FeZrN film, CoZrN film, FeTa are used.
C film or NiFeX film (X: Rh, Nb, Zr,
Hf, Ta, Re, Ir, Pd, Pt, Cu, Mo, M
n, W, Ti, Cr, Au, or Ag) may be used. In particular, an fcc phase microcrystalline film (Co-based nitride film, Co
In the carbonized carbon film and the NiFeX film), the effect of promoting the fcc phase (111) orientation was synergized, Hc was further reduced to ˜250 A / m in the easy axis direction, and the resistance change rate was improved to 10%.

For comparison, a magnetoresistive effect obtained by sequentially laminating a ferromagnetic film, an intermediate layer, a ferromagnetic film and an exchange bias layer similar to those shown in FIG. The magnetic characteristics of the element were examined, and the MH curve thereof is shown in FIGS. 20 and 21. 20 shows the MH curve in the easy axis direction, and FIG. 21 shows the MH curve in the hard axis direction. The film forming conditions were the same as in Table 3 above.

As can be seen from FIG. 20, the coercive force Hc (d in the figure) of the CoFe film not fixed to FeMn is about 2000 A / m, which is the Hc of a normal CoFe single layer film.
It also showed a high value. Further, also in the hard axis direction, as shown in FIG. 21, the coercive force Hc (e in the figure) of the CoFe film not fixed to FeMn is about 1400A.
/ M, which is a high value like Hc of a normal CoFe single layer film, and was not sufficient as a magnetoresistive effect element. (Embodiment 11) As shown in FIG. 22, a base film 36 of Cu or the like having a thickness of about 5 nm is formed on a supporting substrate 30, and an exchange bias layer 34, a ferromagnetic film 32, and a nonmagnetic film are further formed thereon. 33, the ferromagnetic film 32, and the high resistance amorphous layer 3
1 were sequentially formed, and leads 35 were formed on the high resistance amorphous layer 31 to manufacture a magnetoresistive effect element. The film forming conditions were the same as in Table 3 above.

Even in the structure shown in FIG. 22, that is, when the high resistance amorphous layer is formed as a layer above the exchange bias layer, a low Hc could be obtained. Further, since the amorphous layer has a high resistance, even if this layer was the uppermost layer, there was no decrease in the magnetoresistance change rate due to the shunt effect. In this case, it is desirable to provide a base film for controlling the crystal orientation of FeMn. (Example 12) A CoPtCr film 42 having a thickness of 8 nm is formed on a support substrate 41, a resist 43 is applied thereon, and then the resist 43 is patterned into a desired pattern.
As shown in FIG. 23A, etching was performed by ion milling or the like. At this time, the taper angle X of CoPtCr is preferably close to 90 °.

Next, as shown in FIG. 25B, the resist 43 after etching is not removed, and CoFe is removed in this state.
Ferromagnetic film 44 made of alloy, non-magnetic film 4 made of Cu, etc.
5, the ferromagnetic film 44, and the high resistance amorphous layer 46 were sequentially formed to manufacture a magnetoresistive effect element having a spin valve structure. At this time, the taper angle Y of the resist 43 is preferably close to 90 °.

Next, after removing the resist 43, a lead 47 was formed on the high resistance amorphous layer 46. In addition,
The lead 47 may be formed before removing the resist 43. By manufacturing in this way, FIG.
As shown in (C), a spin valve structure sensitive to the interface state can be manufactured without deterioration of characteristics.

As in the above structure, a high coercive force film can be used without using the exchange bias layer made of FeMn or the like as the magnetization fixed film. As a material for the high coercive force film, it is desirable to use a material that can exhibit an appropriate in-plane magnetic anisotropy without using a base film. Therefore, in this example, a CoPtCr film satisfying these characteristics was used as the high coercive force film. (Embodiment 13) As shown in FIG. 24, a high resistance amorphous layer 31, a ferromagnetic film 32 and a non-magnetic film 3 are formed on a supporting substrate 30.
3, the ferromagnetic film 32, and the high-resistance amorphous layer 31 were sequentially laminated, and the lead 35 was formed on the uppermost high-resistance amorphous layer 31 to manufacture a magnetoresistive effect element.

As shown in the structure of FIG. 24, the exchange bias layer made of FeMn, which is the magnetization fixed film, is not used, but the self-bias effect due to the effect of the magnetic field generated by the sense current or the demagnetizing field due to the shape is used to enhance the strength. An antiferromagnetic magnetization arrangement between the magnetic films 32 may be realized.

In this case, the magnetic field generated by the sense current is applied in the film width direction (g direction in the figure) so as to be opposite in the vertical direction with the ferromagnetic film 32 sandwiched therebetween. In order to reduce the magnetic field, the two ferromagnetic films 32 are antiferromagnetically coupled to each other. As a result, the two ferromagnetic films 32 can be antiferromagnetically coupled to each other without the exchange bias layer. Therefore, the signal magnetic field Hs
Is applied in the longitudinal direction of the film (direction f in the figure), the magnetizations of the two ferromagnetic films 32 rotate and become aligned in the longitudinal direction of the film to form a ferromagnetic coupling. As a result, a large Δ due to spin-dependent scattering
R / R can be obtained. (Example 14) As shown in FIG. 25, a thermally oxidized Si substrate 1
A CoCr alloy film as a high-resistance ferromagnetic film 161 was formed on 60 by a beam thickness of 1 nm by an ion beam sputtering method. Next, the first ferromagnetic film 1 is formed on the high resistance magnetic film 161.
62 is a CoFe alloy film having a thickness of 3 nm and a non-magnetic film 16
A Cu film having a thickness of 2 nm and a CoFe alloy film having a thickness of 3 nm were sequentially formed as the second ferromagnetic film 164 to form a spin valve type laminated film.

After that, the antiferromagnetic film 16 is formed on the laminated film.
As No. 5, a FeMn film was formed with a thickness of 15 nm. If necessary, a protective film 166 is formed thereon, and the electrode 1
By forming 67a and 167b (spacing: 10 μm), a spin valve type magnetoresistive effect element 168 was produced.

The resistance change rate of the spin-valve magnetoresistive effect element thus obtained was measured and found to be 14 at room temperature.
It showed a high value of%.

For comparison, a spin valve magnetoresistive effect element was manufactured in the same manner as in Example 14 except that the high resistance ferromagnetic film 161 was not formed. When the characteristics of this spin valve magnetoresistive effect element were evaluated in the same manner as in Example 14, the rate of change in resistance at room temperature was 12%. (Example 16) A Co ₉₀ Fe ₁₀ alloy film as a first ferromagnetic film, a Cu film as a non-magnetic film, and a second film on a sapphire substrate.
Co ₉₀ Fe ₁₀ alloy film as the ferromagnetic film and FeMn film as the antiferromagnetic film were sequentially formed. At this time, the first and second
The rate of change in resistance (Δρ / ρ ₀ ) was measured by changing the thickness (d _FeCo ) of the ferromagnetic film of. The result is shown in FIG.
The first and second ferromagnetic films have the same thickness, and C
The thickness of the u film was 2.2 nm and the thickness of the FeMn film was 15 nm. Further, in the magnetoresistive effect element, Ta, Ni, N excellent in corrosion resistance and the like may be formed on the antiferromagnetic film as needed.
An electrode is formed through a protective film such as iCr. As can be seen from FIG. 26, the MR effect increases when d _FeCo is 5 nm or less. Further, a peak appears near d _FeCo = 3 nm, and a preferable range is 2 to 4 nm.

As the thickness of the sandwich structure of the ferromagnetic film / non-magnetic film (metal thin film) / ferromagnetic film becomes smaller, the electron scattering on the surface not in contact with the metal thin film becomes larger, and the resistance size effect is obtained. Appears. The fluctuation (Δρ) of the resistivity of the sandwich structure is proportional to l ₀ / t, where t is the total film thickness of the sandwich structure and l ₀ is the mean free path. Although it varies depending on various conditions, as is clear from FIG. 26, when the Co-based ferromagnetic film is used, the ferromagnetic film thickness is 5 nm.
The following is preferable in order to obtain a good MR effect.

That is, when a material having a low resistance, for example, a specific resistance of 30 μΩcm or less is in contact with the surface of the ferromagnetic film which is not in contact with the metal thin film, the electrons pass through the interface and the specific resistance of 30 μΩcm or less is obtained. It will flow into the material with the effect, and effective surface scattering will be less likely to occur. Therefore, in order to cause effective surface scattering and utilize the size effect, it is effective to use a material having a thickness of 30 μΩcm or more or a film thickness of a material in contact with the material to be 5 nm or less.

In order to obtain a large MR effect by utilizing the size effect, it is preferable that the film thickness of the Co type ferromagnetic film be 5 nm or less. At this time, as the intermediate metal thin film, C
It is desirable to use a metal having a small specific resistance such as u, Ag, and Au, and the thickness of the intermediate metal thin film is preferably thinner than 5 nm in order to utilize the size effect. Also, when the film thicknesses of the two ferromagnetic films are greatly different, the effect of surface scattering in the two ferromagnetic films is different, so that the magnetoresistance change rate becomes small. Therefore, it is desirable that the ratio of the thicknesses of the two ferromagnetic films be between 1: 1 and 1: 2. (Example 16) As shown in FIG. 27, a sapphire substrate 1
A CuPd alloy film was formed as a non-magnetic film 161 on 60 by RF sputtering to a thickness of 2 nm. Next, on the non-magnetic film 161, a CoFe alloy film with a thickness of 1 nm is formed as the first ferromagnetic film 162, and a Cu film is formed with a thickness of 2 as the non-magnetic film 163.
In this case, a CoFe alloy film having a thickness of 3 nm was sequentially formed as a second ferromagnetic film 164 to form a spin-valve type laminated film.

After that, the antiferromagnetic film 16 is formed on the laminated film.
As No. 5, a FeMn film was formed with a thickness of 15 nm. If necessary, a protective film 166 is formed thereon, and the electrode 1
By forming 67a and 167b, a spin valve type magnetoresistive effect element 171 was produced.

In this magnetoresistive effect element, the antiferromagnetic film 1 is used.
Since the second ferromagnetic film 164 is given unidirectional anisotropy by 65, the magnetization remains fixed in one direction and does not move in a low magnetic field. On the other hand, the first ferromagnetic film 1
62 directs the magnetization in the direction of the magnetic field even in a low magnetic field. Therefore, the angle formed by the magnetizations of the two ferromagnetic films can be freely controlled by changing the external magnetization. The antiferromagnetic film 165 preferably has a thickness of about 1 to 50 nm in order to give effective unidirectional anisotropy to the second ferromagnetic film 164.

The rate of change in resistance of the spin-valve magnetoresistive effect element 171 thus obtained was measured.
Despite having the thin ferromagnetic film 162 of 1 nm, it exhibited a high value of 8% at room temperature. In addition, the spin-valve magnetoresistive effect element 171 has a width of 2 μm ×
Processed into a fine shape with a length of 80 μm and the distance between Cu leads is 2 μm
When used for reproducing high-density magnetic recording with a narrow track width defined by m, Barkhausen noise could be removed.

For comparison, a spin valve magnetoresistive effect element was manufactured in the same manner as in Example 17 except that the nonmagnetic film 161 was not formed. When the characteristics of this spin valve magnetoresistive element were evaluated in the same manner as in Example 17, the rate of change in resistance was as small as 3% at room temperature.

The thickness of the first ferromagnetic film 162 is set to 6 nm.
A spin valve magnetoresistive effect element was produced in the same manner as in Example 16 except that the above was adopted. When the characteristics of this spin-valve magnetoresistive element were evaluated in the same manner as in Example 16, the rate of resistance change was 6% at room temperature.
When high-density recording (narrow track width) was reproduced by a reproducing fine element similar to that in Example 16, Barkhausen noise due to a demagnetizing field was observed. (Example 17) As shown in FIG. 28, a thermally oxidized Si substrate 1
As a thin film 172 having a long mean free path on 60, Ga doped with Te so that the carrier concentration is 10 ²⁰ cm ⁻³
An As film was formed with a thickness of 10 nm by the MBE method. next,
The first ferromagnetic film 162 is formed on the Te-doped GaAs film 172.
A CoFe alloy film having a thickness of 1 nm, a non-magnetic film 163 having a Cu film having a thickness of 2 nm, and a second ferromagnetic film 164 having a CoFe alloy film having a thickness of 4 nm. Was formed.

After that, the antiferromagnetic film 16 is formed on the laminated film.
As No. 5, a FeMn film was formed with a thickness of 15 nm. If necessary, a protective film 166 is formed thereon, and the electrode 1
By forming 67a and 167b, a spin valve type magnetoresistive effect element 173 was produced.

The resistance change rate of the spin valve magnetoresistive effect element thus obtained was measured and found to be 18 at room temperature.
It showed a high value of%. In addition, the spin-valve magnetoresistive effect element is used for reproducing high density magnetic recording.
^{When the} output signal voltage at a sense current having a current density of ⁵ A / cm ² was measured, a good value of 1 mV _pp was obtained.

For comparison, Te-doped GaAs film 172
A spin-valve magnetoresistive effect element was produced in the same manner as in Example 17 except that the above was not formed. When the characteristics of this spin-valve magnetoresistive effect element were evaluated in the same manner as in Example 17, the resistance change rate was as small as 2% at room temperature. Example 18 A 10-nm-thick Cu film was formed as a base film on a glass substrate, and a Co ₉₀ Fe ₁₀ film was formed thereon. The Cu film and the Co ₉₀ Fe ₁₀ film were formed by the RF bipolar sputtering method. The sputtering was performed under the following sputtering conditions by applying a unidirectional magnetic field of about 4000 A / m near the substrate with a permanent magnet during film formation.

Preliminary exhaust 1 × 10 ⁻⁴ Pa or less Ar sputter gas pressure 0.4 Pa High frequency input power CoFe: 300-500 W Cu: 160 W Sputtering speed CoFe: 0.5-1 nm / s Cu: 1 nm / s fabricated Co ₉₀ Fe ₁₀ film of Hc is shown in Figure 29 the thickness of the relationship (hard axis) and Co ₉₀ Fe ₁₀ film.
Further, FIG. 29 also shows, for comparison, a case where a Co ₉₀ Fe ₁₀ film was directly formed on a glass substrate without providing a Cu base film. The coercive force Hc was measured by a vibrating magnetometer.

As can be seen from FIG. 29, the normal Co ₉₀ Fe ₁₀ film having no Cu underlayer has a high Hc of 2000 A / m or more at a film thickness of 20 nm or less. On the other hand, when a Cu underlayer film is provided, the Co ₉₀ Fe ₁₀ film with a film thickness of 20 nm is Hc.
Was slightly reduced, but 400-
Hc was drastically reduced to 900 A / m. As described above, it was found that the Hc of the Co ₉₀ Fe ₁₀ film can be reduced by providing the Cu underlayer film between the glass substrate and the Co ₉₀ Fe ₁₀ film. In particular, if the thickness of the Cu underlayer film is one atomic layer or more, the above Hc reduction effect was recognized. Note that Cu
If a Co film is formed on the underlying film in exactly the same manner, Co
No decrease in Hc was observed as in the case of the Fe film. (Example 19) A Cu base film having a thickness of 5 to 6 nm is formed on a glass substrate, and a Co ₉₀ Fe ₁₀ film, a Cu intermediate layer having a thickness of 2 nm, and a Co ₉₀ Fe ₁₀ film are sequentially formed on the Cu base film. Formed. The film forming conditions for these films were the same as in Example 18.

This laminated film (Cu / CoFe / Cu / Co
FIG. 30 shows the relationship between Hc (hard axis direction) in Fe) and the film thickness of the Co ₉₀ Fe ₁₀ film. Further, FIG.
Like C, without directly providing a Cu underlayer on the glass substrate, C
A film having an o ₉₀ Fe ₁₀ film formed is also shown.

As can be seen from FIG. 30, in the laminated film in which the Cu underlayer is not provided, Hc rapidly increases when the unit Co ₉₀ Fe ₁₀ film thickness is 5 nm or more, but Hc is 80 when the film thickness is 3 nm or less.
It is 0 A / m. Thus, Hc can be reduced simply by providing the Cu intermediate layer. Furthermore, Cu is added to this laminated film.
Hc can be further reduced by providing a base film, and the unit Co ₉₀ Fe ₁₀ film having a thickness of 7 nm or less is 220 to 400 A /
It can be seen that Hc with a low m is obtained. Therefore, C
In the Co ₉₀ Fe ₁₀ laminated film using the u base film and the Cu intermediate layer, Hc can be significantly reduced as compared with the case of Example 18.

Cu5 nm / Co ₉₀ Fe ₁₀ 2.2 nm /
The magnetization curve (easy axis direction) of the laminated film of Cu 2 nm / Co ₉₀ Fe ₁₀ 2.2 nm is shown in FIG. As can be seen from FIG. 31, the residual magnetization is 90% or more even when the magnetic field is 0.
It can be seen that the magnetization of the two Co ₉₀ Fe ₁₀ ferromagnetic films exhibits a ferromagnetic behavior, not an antiferromagnetic behavior. (Example 20) The unit film thickness of the Co ₉₀ Fe ₁₀ film was set to 1.5 nm, the unit film thickness of the Cu film was set to 1.5 nm, and (CoFe /
A Cu) n film was formed under the film forming conditions shown in Example 18, and the relationship between Hc and the number of laminations n was investigated. The result is shown in FIG.
Shown in. In this case, Co ₉₀ Fe ₁₀ film, C on the glass substrate
An examination was made on a laminate in which the u film was laminated in this order and a laminate in which the Cu film and the Co ₉₀ Fe ₁₀ film were laminated in this order (Cu in the first layer is considered to correspond to the base film).

As can be seen from FIG. 32, in the case where the number of laminations is 2, when the Co ₉₀ Fe ₁₀ film is formed first,
Hc is slightly high at 650 A / m, but when the number of laminations is 4 to 8, Hc is as low as 100 to 300 A / m regardless of whether the Co ₉₀ Fe ₁₀ film is first or the Cu film is first. This is because the effect of the Cu underlayer becomes weaker as the number of stacks increases, and C
It is considered that this is because Hc becomes low regardless of the presence or absence of the u base film (the Cu film of the first layer). Note that the magnetization curve in this case also had a shape showing ferromagnetic coupling as in FIG.

From the observation of the cross-section transmission electron microscope and the measurement of the diffraction peak half width of the X-ray diffraction curve, this laminated film has a large crystal grain size, that is, it is continuous at the interface between the Cu film and the Co ₉₀ Fe ₁₀ film. It was found that the crystal grew epitaxially. Therefore, this laminated film is different from a conventional multilayer film such as Fe / C, which exhibits soft magnetism by the microcrystal effect utilizing the crystal growth blocking effect at the interface between the non-magnetic film and the ferromagnetic film, Since there is no extra increase in resistance, it can be applied to a magnetoresistive film using spin-dependent scattering. (Example 21) In the (Co ₉₀ Fe ₁₀ / Cu) n film, Cu
It is known that the magnetization of the ferromagnetic film adjacent to the Cu film is antiferromagnetically coupled or ferromagnetically coupled depending on the film thickness. Fig. 33 shows (Co ₉₀ Fe ₁₀ (1 nm) / Cu)
The relationship between Hs (saturation magnetic field) in the hard axis direction and the film thickness of the unit Cu film in ₁₆ is shown. When the thickness of the Cu film is set to around 1 nm and 2 nm, a large Hs (12 to 240 kA / m) due to antiferromagnetic coupling between adjacent ferromagnetic films is exhibited. In addition, a magnetization curve showing antiferromagnetic coupling in which the residual magnetization is greatly reduced as shown in FIG. 34 in the easy axis direction is also shown. On the other hand, at other film thicknesses, H of a degree corresponding to the induced magnetic anisotropy of Co ₉₀ Fe ₁₀ is obtained similarly to the magnetization curve shown in FIG.
s (1000 to 2000 A / m), and the magnetization curve in the easy axis direction had a residual magnetization of 90% or more, showing no antiferromagnetic coupling.

As can be seen from FIG. 33, ferromagnetic coupling can be obtained by setting the film thickness to an intermediate value of, for example, about 1.5 nm. The ferromagnetic coupling can increase the magnetic permeability in the hard axis direction, which is important for application of a magnetic sensor such as a magnetic head because Hs is low. As described above, in the present embodiment, the film thickness of the Cu film is preferably an intermediate value that does not cause antiferromagnetic coupling, unlike the conventional artificial lattice film exhibiting the giant magnetoresistive effect. (Embodiment 22) The ferromagnetic laminated unit 51 was formed on the substrate 50 under the same film forming conditions as in Embodiment 18. Here, the ferromagnetic lamination unit 51 is composed of the Cu film which is the non-magnetic film and Co ₉₀ Fe which is the ferromagnetic film shown in the twentieth and twenty-first embodiments.
A laminated film consisting of ₁₀ films. Next, a non-magnetic film 52 having a thickness different from that of the non-magnetic film in the ferromagnetic laminated unit 51 was formed on the ferromagnetic laminated unit 51, and the ferromagnetic laminated unit 51 was further formed thereon. Then, FeMn, NiO,
An antiferromagnetic film 53 made of NiCoO or the like was formed, and a protective film 54 was further formed thereon. The protective film 54 is formed as needed. Finally, an electrode terminal 55 was formed on the protective film 54 in order to supply a current to the edge portion, and the magnetoresistive effect element shown in FIG. 35 was manufactured.

Here, the exchange bias is applied to the ferromagnetic lamination unit 51 which is in direct contact with the antiferromagnetic film 53 by forming the ferromagnetic lamination unit 51 and the antiferromagnetic film 53 in a unidirectional magnetic field. You can Since the magnetization of the ferromagnetic film in the ferromagnetic laminated unit 51 exchange-coupled with the antiferromagnetic film 53 is fixed, a CoFe single layer film having a slightly lower soft magnetism may be used instead of the ferromagnetic laminated unit 51. Good. Further, the ferro-coupled CoFe / Cu interface does not necessarily have to be flat. As shown in FIG. 36, a layered Co film is formed in the Cu film.
The same effect is exhibited even when Fe is mixed.

The ferromagnetic lamination unit 51 is (Co ₉₀ Fe ₁₀ 1nm
/Cu1.2nm) ₄ film and non-magnetic film 52 with a thickness of 2.5
nm Cu film, antiferromagnetic film 53 is 10 nm thick FeM
37 and 38 show the magnetization curve and resistance change characteristics (the magnetic field direction is the easy axis direction) of a magnetoresistive effect element in which the n film is used and the protective film 54 is a Cu film having a thickness of 6 nm. The resistance was measured by the 4-terminal method.

As can be seen from FIGS. 37 and 38, H
The magnetization is antiferromagnetically coupled between the two ferromagnetic laminated units 51 at> 800 A / m, and H <500 A / m.
Thus, the magnetizations are ferromagnetically coupled between the two ferromagnetic laminated units 51. That is, H = 500 to 800 A /
It can be seen that the magnetization changes from the ferromagnetic coupling to the antiferromagnetic coupling between m. This H = 500 to 800 A / m
The resistance greatly changes in a slight magnetic field region of, that is, a slight hysteresis, and the resistance change rate ΔR / R at this time
Is 8%.

[0180] For comparison, the magnetization of the magnetoresistive element of a spin valve structure shown in Figure 35 consisting of Co ₉₀ Fe ₁₀ single layer film (which ferromagnetic multilayer unit 51 is replaced with a Co ₉₀ Fe ₁₀ single layer film) The curves and resistance change characteristics are shown in Fig. 3, respectively.
9 and FIG. 40. As can be seen from FIGS. 39 and 40, the magnetization curve has a larger hysteresis than the resistance change of FIG. 38, and as a result, the resistance change characteristic also has a large hysteresis. Further, ΔR / R is about 6.5%, which is smaller than the resistance change in FIG.

From the above description, the magnetoresistive effect element of the spin valve structure using the ferromagnetic laminated film of the present invention has good soft magnetism and can obtain a large resistance change with a slight magnetic field.
Further, it can be seen that the resistance change rate is large because the Co ₉₀ Fe ₁₀ / Cu interface exists inside the ferromagnetic laminated unit.

Although the embodiments of the (CoFe / Cu) n laminated film have been described in detail above, this spin valve structure has another ferromagnetic film (for example, NiFe, NiFeCo, C).
The same effect can be expected in the lamination of (i.e., etc.) and another non-magnetic film (Cu-based alloy, etc.). Next, in the spin valve structure shown in FIG. 35, the rate of change in resistance in the easy axis direction and Hc when the ferromagnetic laminated unit 51 is changed to various ferromagnetic coupling multilayer films are shown in Table 5 below.

[0183]

[Table 5] As can be seen from Table 5, even when a ferromagnetic multilayer film of a combination other than CoFe / Cu is used, Hc can be reduced and resistance equal to or higher than that of the spin valve film using a single-layer magnetic film (see Table 2). It can be seen that the rate of change can be achieved. (Embodiment 23) As a ferromagnetic laminated unit 51 on the substrate side in FIG. 35, a Cu base film with a thickness of 4 nm and Co ₉₀ F with a thickness of 5 nm
41A and 41B show the magnetization curve and the resistance change characteristic when using e ₁₀ and using a Co ₉₀ Fe ₁₀ single layer film having a thickness of 8 nm for the ferromagnetic laminated unit 51 on the antiferromagnetic film 53 side, respectively.
(B) and FIG.

As can be seen from FIG. 41 (A), Hc has a relatively large value of 800 A / m or less in the easy axis direction, but as shown in FIG. 41 (B), it is 1 in the hard axis direction.
It shows a low value of 00 A / m or less. Further, as can be seen from FIG. 42, the resistance change rate ΔR / R is 7.2 in the easy axis direction.
%, And 2.8% in the hard axis direction. The low resistance change rate in the hard axis direction is considered to be insufficient antiferromagnetic alignment due to ferro-coupling between both ferromagnetic layers, and the hard magnetic film promotes antiparallel magnetization alignment. By applying a bias magnetic field that
/ R can be obtained. That is, the Cu base film and Co
Good soft magnetism and high ΔR even when using a laminated film of ₉₀ Fe ₁₀ films
Both / R are obtained. (Example 24) At least two ferromagnetic film laminated units 51 used in Example 22 and a nonmagnetic film 52 having a different thickness from the nonmagnetic layer in the ferromagnetic film laminated units 51 are alternately arranged on the substrate 50. Stacked more than once. Further, a protective film 54 was formed on the uppermost non-magnetic film 52. The protective film 54 is formed as needed. Finally, the electrode terminal 55 for supplying a current to the edge portion was formed to manufacture the magnetoresistive effect element shown in FIG. The ferromagnetic laminated unit 51 is (Co ₉₀
Fe ₁₀ 1 nm / Cu 0.6 nm) ₄ film, the non-magnetic layer 52 was a Cu film with a thickness of 2.2 nm, and the number of laminations n was 8, but the magnetization curve in the hard axis direction and the resistance change characteristics are shown in FIG. 45.

As can be seen from FIGS. 44 and 45, the saturation magnetic field Hs shows a relatively small value of 6000 A / m,
Hc shows a small value of 240 A / m. At this time, the rate of resistance change is 12% or less, the magnetic field at which the resistance change saturates almost coincides with the saturation magnetic field Hs in the magnetization curve, and the hysteresis substantially coincides with Hc in the magnetization curve. It can be seen from this that a large resistance change rate is exhibited with a slight magnetic field. (Example 25) (Co ₉₀ Fe ₁₀ 1 nm / Cu 1.1 nm) was formed on the (110) surface of the MgO substrate 60 processed into a mirror surface state.
₁₆ laminated film 61 was formed. This laminated film 61 was patterned into a 1 × 8 mm ² stripe pattern using a metal mask. Next, an electrode terminal 62 for supplying a current to the edge portion was formed on the laminated film 61 to manufacture a magnetoresistive effect element. A thickness of 5.5 nm is formed as a protective film on the laminated film 61.
The Cu film may be formed. In addition, the composition of the CoFe alloy film shows a large rate of resistance change [Journal of Japan Applied Magnetics, 16 , 313 (1992)] and Co ₉₀ from the viewpoint of soft magnetic properties.
It was set to Fe ₁₀ .

In this case, a Co ₉₀ Fe ₁₀ film was formed on the (110) surface of the MgO substrate 60. This is because if a Cu film is used, a large resistance change of 10% or more cannot be obtained. In FIG. 46, the wavy line shown in the laminated film 61 shows the cross section of the main growth surface. An MR sense current (Is) is passed in the direction in which the main growth surface is fluctuating.

Here, as a film forming apparatus for forming the laminated film 61, a multi-source simultaneous sputtering apparatus was used. This sputtering apparatus is configured so that a Co ₉₀ Fe ₁₀ target can be RF sputtered and a Cu target can be DC sputtered, and films are formed by passing a substrate on which a DC bias is applied alternately on each target. is there. A cryopump was used as the main exhaust pump. Using this film forming device, the inside of the vacuum chamber is set to 5 × 1.
After evacuating to below 0 ^-7 Torr, put A in the vacuum chamber.
Sputtering was performed by introducing r gas at about 3 mTorr.

The resistance change rate and the crystal structure of the obtained magnetoresistive effect element were examined. The rate of resistance change was measured by measuring the resistance change in the static magnetic field direction by the four-terminal method. The current density at this time was 2.0 to 2.5 KA / cm ² . In addition, the crystal structure was evaluated by measuring a θ-2θ scan and a rocking curve regarding the main diffraction plane by an X-ray diffraction method under the following measurement conditions.

X-ray diffraction measurement conditions (1) θ-2θ scan Cu-Kα, 40 kV, 200 mA Scan width: 2θ = 2 to 100 ° Step width: 0.03 ° Coefficient time: 0.5 seconds (2) Rocking curve Cu-Kα, 40 kV, 200 mA Scan width: 2θ = 20 to 60 ° Step width: 0.04 ° Coefficient time: 0.5 seconds FIGS. 47A and 47B show the laminated film of the magnetoresistive element. The X-ray diffraction curve by a (theta) -2 (theta) scan is shown.
As shown in FIG. 47 (B), fc near 2θ = 75 °
A strong diffraction peak corresponding to c-phase (220) plane reflection can be confirmed. From this, it can be seen from the X-ray diffraction curve that the main growth plane of the laminated film is the fcc phase (220) plane having strain in one direction. The peak near 2θ = 4 ° in FIG. 47A is diffraction due to the stacking period (up to 2.1 nm).

Next, regarding this main growth surface, [100]
Rocking curves were measured from the axial direction and the [110] axis direction. The results are shown in FIGS. 48 (A) and 48 (B).
Shown in. FIG. 48A shows a rocking curve measured from the [110] axis direction. From this, one peak can be confirmed near θ = 38 °. On the other hand, FIG. 48 (B) shows a rocking curve from the [100] axis direction. From this, the existence of two peaks near θ = 33 ° and 41 ° can be confirmed.

FIG. 48 is shown in FIGS. 49 (A) and 49 (B).
The conceptual diagram of the membrane structure judged from the rocking curve of FIG. The undulated layer in FIG. 49 (A) is f on the main growth surface.
The cc phase (110) plane is shown. The average crystal growth plane measured by the θ-2θ scan X-ray diffraction method is (110), but this (110) plane fluctuates in the [100] axis direction. On the other hand, the fluctuation in the [110] axis direction is extremely small.
This corresponds to two peaks (measured in the [100] axis direction) of the rocking curve shown in FIG. 48 (B) and one peak (measured in the [110] axis direction) shown in FIG. 48 (A).

FIG. 49B shows the in-plane component distribution of the normal to the growth surface. The in-plane anisotropy of the film has an in-plane distribution that is large in the [100] axis direction and small in the [110] axis direction due to a large fluctuation in the [100] axis direction.
As will be described later, the resistance change rate (ΔR / R) when the MR sense current is passed in the [110] axis direction is about 30%, whereas when the MR sense current is passed in the [100] axis direction. , About 3
Indicates 5%.

Next, the magnetic characteristics of this laminated film were measured.
Magnetic curves based on the results are shown in FIG. 50 (A) and FIG.
It shows in (B). FIG. 50A shows an external magnetic field H of [100].
The magnetization curve when applied parallel to the axis is shown in FIG.
(B) shows a magnetization curve when the external magnetic field H is applied parallel to the [110] axis. Note that the magnetic characteristics of the magnetoresistive effect element are the maximum applied magnetic field of 1.2 M with a vibration type magnetometer (VSM).
It was measured in A / m. The magnetization amount M of the magnetization curve is shown by normalizing the saturation magnetization Ms.

As can be seen from FIGS. 50 (A) and 50 (B), the [100] axis is the easy magnetization axis and the [110] axis is the hard magnetization axis. At this time, the saturation magnetic field of the easy axis is about 240 kA / m, and the saturation magnetic field of the hard axis is about 96.
It is 0 kA / m.

As described above, in this embodiment, the laminated film in which the ferromagnetic film and the non-magnetic film are laminated at least once in sequence on the substrate is provided, and the direction of the sense current is the crystal orientation plane of the laminated film. Provided is a magnetoresistive effect element characterized by being set in a direction along a fluctuation direction.

In this example, the normal to the main crystal orientation plane of the laminated film has a component in the film plane due to the fluctuation of the crystal orientation plane, and the in-plane component has anisotropy. Alternatively, the normal to the plane defect generated in the crystalline laminated film has fluctuation within the film surface, and this fluctuation has anisotropy within the film surface. The direction in which the anisotropy is strong is a direction in which ferromagnetic atoms and nonmagnetic atoms are likely to be mixed on the atomic plane where the film grows.

By passing the sense current in that direction, that is, in the direction in which the anisotropy due to the in-plane component of the film is maximized, the probability that electrons are spin-dependent scattered is increased. As a result, the magnetoresistive effect element exhibits a higher rate of resistance change. (Example 26) By changing the bias applied to the substrate,
Various magnetoresistive effect elements having the same laminated film structure as in Example 25 were produced. FIG. 51 shows the bias voltage dependence of the resistance change rate. The measurement was carried out by passing a current in parallel with the [100] axis and the [110] axis which were orthogonal to each other on the (110) plane of the MgO substrate. As can be seen from FIG. 51, the bias dependence of the resistance change rate is weak on each axis,
The value is about 35% on the [100] axis and about 30% on the [110] axis. That is, it can be seen that the [100] axis has a larger resistance change rate than the [110] axis. (Example 27) A laminated film was formed of (Cu 2 nm / Co ₉₀ Fe ₁₀ 1n).
m) A magnetoresistive effect element was produced in the same manner as in Example 25 except that ₁₆ films were formed.

When the thickness of the Cu film is increased to 2 nm as described above, the rate of change in resistance when a current is passed in the [100] axis direction is about 25%, and about 19% in the [110] axis direction. Met. Therefore, it is understood that the direction dependence of the resistance change rate is maintained even if the thickness of the Cu film is increased. Also in this case, the rocking curve of the main growth plane (fcc phase (220) plane) shows [1
Two peaks were confirmed on the [00] axis, and one peak was confirmed on the [110] axis as shown in FIG.

The film thickness of the Cu film and C
Even if the film thickness of the o ₉₀ Fe ₁₀ film is changed from 0.3 nm to 10 nm, the tendency of the rocking curve is the same as the above, and the fluctuation is larger on the [100] axis. The rate of change in resistance also tended to be larger on the [100] axis.

[0200] Further, the number of lamination is set to 2 to 70 with the same constitution.
The tendency of the rocking curve and the rate of change in resistance did not change even when the temperature was changed to 0, and a larger change in resistance was obtained when a sense current was passed in the [100] axis direction. (Example 28) A laminated film was formed into (Ru 1 nm / Co ₉₀ Fe ₁₀ 1n).
m) A magnetoresistive element was produced in the same manner as in Example 26 except that the ₁₆ film was used.

The ΔR / R of this magnetoresistive effect element is [1
[00] is [110] when a sense current flows in the axial direction.
It was larger than when the sense current was passed in the axial direction. Also,
The above tendency was observed even when the thickness of the Ru film was changed.

This phenomenon is caused by C instead of the Co ₉₀ Fe ₁₀ film.
It could be confirmed even when the o film was used. In addition to Ru, A
Even if g, Au, Pd, Pt, or Ir is used as the material of the laminated film, it depends on the axial direction on the (110) plane of the MgO substrate.
A difference of R / R could be confirmed. (Example 29) A laminated film was formed into (Cu1.1 nm / Ni ₈₀ Fe ₂₀
A magnetoresistive effect element was produced in the same manner as in Example 25 except that the film thickness was 1.5 nm) ₁₆ .

The laminated film of this magnetoresistive effect element [10
When a sense current was passed in the [0] axis direction, the resistance change rate was 21%. On the other hand, the resistance change rate was 17% when the sense current was passed in the [110] axis direction. Also,
This laminated film is also the same as the case of the Co ₉₀ Fe ₁₀ / Cu laminated film,
The crystal growth surface was the fcc phase (110) surface, and it was found from the rocking curve measurement that the growth surface fluctuated in the [100] axis direction. The same tendency was exhibited even when the thickness of the Ni ₈₀ Fe ₂₀ film and the thickness of the Cu film were changed from 0.5 nm to 50 nm.

Further, Co and CoF are used as materials for the ferromagnetic film.
Even if an e alloy, NiFe alloy, Fe, FeCr alloy or the like is used, Cu, Au, Ag, Cr, R are used as the material of the non-magnetic film.
It was found that even if u, CiNi alloy or the like is used, a large resistance change rate is exhibited if the crystal axis direction in which the main growth surface of the laminated film is fluctuating and the sense current direction are parallel. (Example 30) A Co film having a thickness of 1.5 nm, a Ge film having a thickness of 50 nm, and an Au film having a thickness of 1.5 nm were formed on the (110) plane of a GaAs substrate. Furthermore, MBE on it
53 (Cu 0.9 nm / Co ₉₀ Fe ₁₀
1 nm) ₂₀ laminated film was formed. In the figure, 69 indicates a Cu film,
71 indicates a Co ₉₀ Fe ₁₀ film. Furthermore, a Ge film having a thickness of 5 nm was formed on the laminated film as a protective film to manufacture a magnetoresistive effect element. This laminated film showed fcc phase (111) plane growth. At this time, regardless of the direction of the sense current,
The rate of resistance change was about 15%.

Next, a magnetoresistive effect element was produced with the Au underlayer having a thickness of 0.8 nm and the other structures being the same as above.

Observation of the obtained two magnetoresistive effect elements with a transmission electron microscope revealed that the thickness of the Au underlayer was 1.5.
The nanometer type had almost no lattice defect and had extremely good crystallinity. On the other hand, the Au underlayer has a thickness of 0.
The 8 nm one showed {111} plane orientation, but {1
A stacking fault was observed because the {00} plane slid in the <110> axis direction. Further, when the resistance change rate in the <211> axis direction and the <110> axis direction in this magnetoresistive effect element was measured, it was about 15% in the <110> axis direction,
It increased to 17% in the <211> direction. As a result,
It can be seen that the presence of the directional defect causes the sense current direction dependence of the resistance change rate.

FIG. 53 shows an atomic arrangement diagram of the laminated film in FIG. When the {100} atomic plane shifts in the <110> direction, a current flows in the <211> direction.
It can be seen that in the case of flowing in the <110> direction, the number of interfaces encountered per unit length is different, and is larger in the <211> direction.
The crystal axis direction dependence of the number of spin-dependent interface scattering sites of conduction electrons generated by lattice defects having such a directivity is
It was found that twin defects were generated in addition to the stacking faults described above. The example will be described below.

Thickness of 3 nm on (100) surface of GaAs substrate
Au underlayer film is formed, and (Co ₉₀ Fe ₁₀
1 nm / Cu1.1 nm) ₁₆ laminated film was formed. This laminated film showed the fcc phase (100) plane orientation. At this time, <1
Twins were generated with the 11> axis as the central axis. FIG. 55 shows the atomic arrangement when the cross section of the laminated film is observed from the <110> direction. As can be seen from FIG. 54, twinning around the <111> axis causes Cu in the <110> direction,
It can be seen that an interface with Co or Fe atoms appears.

The dependence of the resistance change rate of this laminated film on the sense current direction was measured in the <110> axis direction and the <100> axis direction. FIG. 55 shows the relationship between the twin planes and the current direction of the laminated film grown on the {100} plane and the resistance change rate. FIG. 55
As can be seen from the above, the resistance change rate is less than the sense current <110
It shows a value of 18% when passed in the> axis direction, and a value of 16% when a sense current is passed in the <100> axis direction. Thus, the resistance change rate of the <110> axis intersecting the {111} plane at a large angle appeared to be high. On the other hand, when twins did not occur, the dependency of the resistance change rate on the sense current direction could not be confirmed. (Example 31) On a glass substrate (Cu1.1 nm / Co ₈₁
Fe ₉ Pd ₁₀ 1 nm) ₁₆ artificial lattice film was formed. The artificial lattice film was formed while applying a DC bias to the substrate. FIG. 56 shows the dependence (bias dependence) of the DC bias applied to the substrate by measuring the resistance change rate while changing the magnitude of the DC bias applied.

As can be seen from FIG. 56, the resistance change rate increases as the DC bias increases, and shows a maximum value of about 28% at a bias of -50V. Furthermore, when the DC bias is increased, the rate of resistance change decreases.

When the crystallinity of various artificial lattice films produced by changing the DC bias was evaluated, the main growth planes of all the artificial lattice films were fcc phase (111) plane growth. Here, 2θ = 4 reflected from the stacking period (2.1 nm)
Long-period structure reflection intensity around 2 ° and 2θ = 44 °
The bias intensities of the peak intensity of the main growth plane reflected from the fcc phase (111) plane appearing in the vicinity are shown in FIGS. 57 and 58.

As can be seen from FIG. 57, the bias dependence of the long period structure reflection intensity shows a slight maximum at a bias of about −20 V, but it cannot be said that there is a strong correlation with the bias. Further, as can be seen from FIG. 58, fc
Regarding the bias dependence of the c-phase (111) plane reflection intensity, a slight maximum is shown near the bias of −10 V, but it cannot be said that there is a strong correlation with the bias.

Further, by using the CoFe alloy system as the ferromagnetic film, bulk scattering of spin-dependent scattering becomes large, and the interface structure becomes less sensitive than in the case of using the Co system film as the ferromagnetic film. It is reported that when a Co-based film is used as the ferromagnetic film, the rate of resistance change greatly depends on the film structure.

Next, FIG. 59 shows the bias dependence of the coercive force (Hc). As can be seen from FIG. 59, bias -5
Good soft magnetic characteristics of 200 A / m or less are shown up to about 0 V, but the coercive force starts to increase from about -60 V. Therefore, by selecting the magnitude of the applied DC bias, it is possible to select the optimum conditions of the resistance change rate and the coercive force. Even when a Si substrate, a ceramic substrate, a GaAs substrate, or a Ge substrate was used instead of the glass substrate, the optimum points of the resistance change rate and the coercive force could be similarly selected. (Embodiment 32) Here, an embodiment of the present invention in which the signal magnetic field is detected by the magnetization rotation of both of the two ferromagnetic films having the spin-dependent scattering ability will be described.

As shown in FIG. 60, a base film 81 for controlling the orientation of an antiferromagnetic film, an antiferromagnetic film 82, a ferromagnetic film 83 having a spin-dependent scattering ability, a nonmagnetic film 84, on a substrate 80,
The ferromagnetic film 85 and the antiferromagnetic film 82 were sequentially formed.
Further, an electrode terminal 86 was formed on the uppermost antiferromagnetic film 82. A protective film may be formed on the antiferromagnetic film 82 if necessary. The material of the base film 81 is Cu, CuV, Cu when the antiferromagnetic film 82 is FeMn.
Cu alloy such as Cr, non-magnetic fcc phase such as Pd or N
A metal having a magnetic fcc phase such as iFe or CoFeTa is desirable. At this time, a good exchange bias can be provided even if the magnetic material has a smaller film thickness (that is, less shunt diversion). The antiferromagnetic film 82 is made of FeMn, NiO,
It is made of PtMn or the like and has a film thickness of 5 to 50 nm. The ferromagnetic films 83 and 85 are made of NiFe, Co, CoFe, NiF.
It is made of eCo and has a thickness of 0.5 to 20 nm.
The nonmagnetic film 84 is made of Cu, Au, Ag or the like, and has a film thickness of 0.5 to 10 nm. Further, the antiferromagnetic film 82 does not need to be formed on the entire surface of the ferromagnetic film 85, and the ferromagnetic film 83
It may be formed only on the edge portions (near the electrode terminals 86) on both sides.

At least during the formation of the ferromagnetic film 83, a static magnetic field in one direction is applied in the x direction (sense current direction) in FIG. As a result, an exchange coupling bias magnetic field is applied to the ferromagnetic film 83 in the static magnetic field direction. On the other hand, at least during the film formation of the antiferromagnetic film 82, a static magnetic field is applied in a direction (minus x direction) different from the magnetic field direction applied during the film formation of the ferromagnetic film 83 by 180 °. As a result, the ferromagnetic film 83 is 1
An exchange coupling bias magnetic field is applied to the ferromagnetic film 85 in a direction different by 80 °. As a result, the angles formed by the magnetizations of the two ferromagnetic films 83 and 85 are antiparallel when the signal magnetic field is zero. The signal magnetic field Hs is applied in the y direction in the figure.

As a method of applying a bias magnetic field in the opposite direction to the ferromagnetic films 83 and 85 by the antiferromagnetic film 82, there is the following method. Films having different Neel temperatures are used as the two antiferromagnetic films 82, and the static magnetic field heat treatment is performed at a temperature higher than these Neel temperatures. Direction 180
° Invert. As a result, a bias magnetic field in the opposite direction can be applied to the ferromagnetic films 83 and 85.

Unlike the conventional spin-valve structure film, the present embodiment utilizes the magnetization rotation of the ferromagnetic film to which the exchange bias from the antiferromagnetic film is applied, so that the exchange bias magnetic field is Barkhausen. It is desirable that the magnetic field is not so strong as to suppress noise. For example, it depends on the track width of the applicable head, but it is 5 kA at maximum.
/ M. However, in the current spin-valve structure film, it is general to use an exchange bias magnetic field by an antiferromagnetic film made of FeMn. In this case, FeM
If an n film and a ferromagnetic film such as a NiFe film are directly laminated, 10
An exchange bias of kA / m or more will occur. In order to reduce the exchange bias, a method for inserting an exchange bias adjusting film, for example, a ferromagnetic film or a non-magnetic film having a low saturation magnetization, is inserted between the antiferromagnetic film and the ferromagnetic film, or shown in FIG. Thus, the non-magnetic films 87 and 88 are interposed in the respective ferromagnetic films 83 and 85, that is, the ferromagnetic films 83 and 8
5 to 83a and 83b, 85a and 85b, respectively
There is a way to separate.

In the method of interposing the nonmagnetic film in the ferromagnetic film, the ferromagnetic films 83a and 85 on the side in contact with the antiferromagnetic film 82 are used.
A strong exchange bias is applied to a, but a weak exchange bias is applied to the ferromagnetic films 83b and 85b on the side not in contact with the antiferromagnetic film 82. The ferromagnetic film 8 on the side not in contact with the antiferromagnetic film 82 depends on the type of material and the film thickness of the nonmagnetic films 87 and 88.
The magnitude of the exchange bias to 3b and 85b can be reduced.

Here, the angle formed by the magnetizations of the ferromagnetic films 83a and 83b and the angle formed by the magnetizations of the ferromagnetic films 85a and 85b are changed from the ferromagnetic arrangement to the antiferromagnetic arrangement by the magnetization rotation by the signal magnetic field. However, the angle formed by the magnetizations of the ferromagnetic films 83b and 85b in the central part of the film is changed from antiferromagnetic alignment to ferromagnetic alignment. Therefore, the spin-dependent scatterings of the former and the latter cancel each other out. Therefore, the ferromagnetic films 83a and 85a and the non-magnetic films 87 and 8
It is desirable that the material of No. 8 has a high resistance without spin-dependent scattering ability. Further, it is desirable that the thickness of the ferromagnetic films 83a and 85a on the side in contact with the antiferromagnetic film 82 be smaller than the thickness of the ferromagnetic films 83b and 85b on the side not in contact with the antiferromagnetic film 82.

With the above arrangement, the magnetization directions of the ferromagnetic films 83 and 85 can be aligned antiparallel when the magnetic field is zero. As a result, firstly, even when a signal magnetic field is applied in the hard axis direction (y direction in the drawing) suitable for the magnetic head, the magnetization rotation of both ferromagnetic films causes the angle formed by the magnetizations of both ferromagnetic films to be 0 to 0. A state of changing up to 180 ° can be realized, and a resistance change rate as high as that in the easy axis direction can be realized. Second,
Since a bias magnetic field is applied to the two ferromagnetic films, the domain wall can be eliminated from both ferromagnetic films, and Barkhausen noise can be suppressed. Thirdly, in the method in which the sense current and the signal magnetic field are orthogonal to each other, both the ordinary magnetoresistive effect and the resistance change due to spin-dependent scattering, which are remarkable when a NiFe film or the like which is conventionally canceled by the spin valve structure, are used. It is possible to expect an increase in ΔR / R. (Example 33) In Example 32, a method of making the magnetizations of both ferromagnetic films antiparallel by using two antiferromagnetic films was shown. However, it is not always necessary to apply the bias magnetic field only with the antiferromagnetic film, and the leakage magnetic field from the hard magnetic film or the demagnetizing field generated when processed into a fine shape may be used. Next, an example thereof will be described.

As can be seen from FIG. 62, the ferromagnetic film 91 and the nonmagnetic film 9 having the spin-dependent scattering ability on the substrate 90.
2 and the ferromagnetic film 93 were formed. Ferromagnetic films 91, 9
The film thicknesses of 3 and the non-magnetic film 92 were the same as those in Example 32. An antiferromagnetic film 94 having a thickness of 2 to 50 nm was formed thereon, and an exchange bias was applied to the ferromagnetic film 93. further,
A hard magnetic film 95 made of CoPt and CoNi and having a thickness of 10 to 50 nm was formed thereon. The electrode terminal 96 was formed on the hard magnetic film 95. All film formations were performed in a static magnetic field (x direction in the figure).

Then, a magnetic field of 400 to 800 kA / m was applied in the same direction as the exchange bias magnetic field direction by the antiferromagnetic film 94 to magnetize the hard magnetic film 95 in the x direction. As a result, a bias magnetic field was applied to the ferromagnetic film 91 in the minus x direction by the leakage magnetic field from the edge of the hard magnetic film 95, and the magnetizations of the ferromagnetic films 91 and 93 became antiparallel.
Although the bias magnetic field from the hard magnetic film 95 is applied to the ferromagnetic film 93 as well, the exchange bias force is set so that the exchange bias magnetic field from the antiferromagnetic film 94 is stronger. A magnetized state can be realized. In addition,
The hard magnetic film 95 and the antiferromagnetic film 94 do not have to be formed on the entire surface of the ferromagnetic film 93, and may be formed only on the edge portion (in the vicinity of the electrode terminal 96) of the ferromagnetic film 93.

It is to be noted that, in 95 of FIG. 62, a ferromagnetic film close to soft magnetism can be used instead of the hard magnetic film. In this case, it is necessary to stack the ferromagnetic films close to soft magnetism so that the exchange bias is applied from the antiferromagnetic film 94. When the exchange bias is applied to the ferromagnetic film 95, the magnetization of the ferromagnetic film 95 can be fixed in one direction.
Further, by processing into a fine pattern shape that is indispensable for the magnetoresistive effect, it can be applied in a direction different from the exchange bias magnetic field from the antiferromagnetic film 94 added to the ferromagnetic film 93 by 180 °. At this time, by adjusting the film thickness and the saturation magnetization of the ferromagnetic film 95, a bias magnetic field having a desired strength is applied to the ferromagnetic film 9.
Can be given to 1.

By adjusting the resistivity and film thickness of the ferromagnetic film 95, a desired shunt shunt operating point bias can be applied. Here, in the ferromagnetic film 95, the antiferromagnetic film 9
4 required for exchange coupling with 4 (antiferromagnetic film 94
And a crystalline ferromagnetic film having a crystal structure and a lattice constant similar to those of the antiferromagnetic film 94 for epitaxial growth, such as a NiFe film, a CoFe film, a CoFeTa film, and a CoFeP film.
It is difficult to satisfy both the characteristics required for the magnetostatic coupling bias and the operating point bias (the film d is desirable) (the resistivity is too low for the crystalline film). Therefore, the ferromagnetic film 95 includes a magnetic film for exchange coupling (NiFe, CoFe-based ferromagnetic film, etc.) that is in contact with the antiferromagnetic film 94 and a ferromagnetic film for bias (Co-based amorphous film, nitrided film such as FeTaN). It is desirable that the crystal film, or a carbide microcrystal film such as FeZrC) has a two-layer structure in which ferromagnetic exchange coupling is performed at the interface.

In the case of the structure shown in FIG. 62, the hard magnetic film 95
Since the sense current from the electrode terminal 96 is shunted to the
It is inevitable that R will decrease to some extent. This problem can be solved by the structure shown in FIGS.

That is, as shown in FIG. 63, the substrate 90
Similar to FIG. 62, the antiferromagnetic film 94 is formed thereon, and thereafter the hard magnetic film 95 is formed near both sides of the antiferromagnetic film 94. Electrode terminals 96 are formed on the inside thereof at intervals corresponding to the track width. As a result, it is possible to prevent a sense current from flowing through the hard magnetic film 95, and suppress a decrease in ΔR / R.

On the other hand, as shown in FIG. 64, the hard magnetic film 95 is first formed on the substrate 90, and the ferromagnetic film 91, the nonmagnetic film 92, the ferromagnetic film 93, and the insulating film 97 are formed on the hard magnetic film 95. And an antiferromagnetic film 94 are sequentially formed, and electrode terminals 96 are further formed.
To form. At this time, a static magnetic field is applied during film formation to apply a predetermined exchange bias magnetic field from the antiferromagnetic film 94 to the ferromagnetic film 93. After the film formation, the hard magnetic film 95 is magnetized in the same direction as the exchange bias direction. Even with this method, the ferromagnetic film 9
Bias magnetic fields in opposite directions can be applied to 1 and 93, and moreover, current can be prevented from flowing through the hard magnetic film 95. The insulating film 97 is composed of the hard magnetic film 95 and the ferromagnetic film 9.
The exchange coupling with 1 also has an effect of preventing an excessive bias magnetic field from being applied.

Further, as shown in FIG. 65, a ferromagnetic film 91, a nonmagnetic film 92, a ferromagnetic film 93, and an antiferromagnetic film 94 are sequentially formed on the substrate 90. Next, this laminated film is finely processed into a predetermined shape. This fine processing is performed by ion milling or the like by forming a mask using a resist or the like. After that, a hard magnetic film 95 is formed on the side of the ferromagnetic film 91 by the lift-off method using the remaining mask. Finally, the hard magnetic film 95 is magnetized in the direction opposite to the exchange bias applied to the ferromagnetic film 93. Even with this method, the ferromagnetic film 9
Bias magnetic fields in opposite directions can be applied to 1 and 93, and moreover, current can be prevented from flowing through the hard magnetic film 95. (Example 34) In the spin valve structure shown in FIG. 61, a 5 nm thick Cu underlayer containing 1 at% Cr on a glass substrate 80 and a 15 nm thick FeM film as an antiferromagnetic film 82.
Ni ₈₀ Fe with a thickness of 1 nm as the n film and the ferromagnetic film 83a
₂₀ films, the nonmagnetic film 87 contains 1 at% of Cr and has a thickness of 1.
5 nm Cu film and 6 nm thick Ni ₈₀ as ferromagnetic film 83b
Fe ₂₀ film, Cu film with a thickness of 2.5 nm as the non-magnetic film 84,
The ferromagnetic film 85b is a Ni ₈₀ Fe ₂₀ film having a thickness of 6 nm, and the non-magnetic film 87 is a Cu film having a thickness of 1.5 nm and containing 1 at% Cr.
1 nm thick Ni ₈₀ Fe ₂₀ film as the ferromagnetic film 85a,
Further, as the antiferromagnetic film 82, a FeMn film having a thickness of 15 nm was sequentially formed.

These films were formed at once by a two-pole sputtering method in a static magnetic field using a permanent magnet without breaking the vacuum. The permanent magnet is not integrally attached to the substrate holder. Further, at this time, the preliminary exhaust pressure is set to 1 × 10 ⁻⁴ Pa or less and the Ar gas pressure is set to 0.4 Pa. After the ferromagnetic film 83 is formed, the substrate holder is rotated 180 ° and the permanent magnet is used. The direction of the bias magnetic field (about 4000 A / m) was reversed by 180 °. In this way, a laminated film having a spin valve structure capable of realizing the antiparallel state of the magnetizations of both ferromagnetic films at the signal magnetic field of 0 was produced.

The resistance of the obtained laminated film was measured by the 4-terminal method. Specifically, a constant current of 1 mA is applied to the ferromagnetic films 83 and 85 in the easy axis direction so that the width of the film in the hard axis direction is set to 1.
The voltage between 4 mm was measured as mm. The magnetic field was applied by the Helmholtz coil in the hard axis direction of the ferromagnetic films 83 and 85. As a result, the obtained resistance-magnetic field characteristic is shown in FIG.

In FIG. 66, the resistance is the maximum magnetic field (16 k
The value in A / m) is shown normalized to 1. When the magnetic field is 0, the magnetizations of the ferromagnetic films 83 and 85 are antiparallel to each other, so that the resistance exhibits the maximum value. The resistance drops sharply when a magnetic field is applied. In particular, in a magnetic field of 2000 A / m or more, the resistance shows an approximately constant value. Resistance change rate of about 3.8% or less is 2000
It can be seen that this occurs in a slight magnetic field range of A / m or less. In addition, almost no hysteresis or noise is recognized in this resistance-magnetic field characteristic. That is, by using this laminated film having the spin valve structure, a magnetic head having extremely high sensitivity and less noise can be obtained.

Further, a spin valve type magnetoresistive effect element shown in FIG. 60 was produced, and the relationship between the thickness of the nonmagnetic layer 84 (Cu) and the resistance change rate was investigated. The results are shown in Table 6 below. A NiFe film having a thickness of 5 nm was used as the base film, a NiFe film having a thickness of 8 nm was used as the ferromagnetic films 83 and 85, and a FeMn film having a thickness of 10 nm was used as the antiferromagnetic film 82.

[0234]

[Table 6] As can be seen from Table 6, the resistance change rate rapidly increased as the Cu thickness decreased, and a high resistance change rate of 9% was obtained when the Cu thickness was 1.2 nm. This is because a relatively large anti-parallel bias magnetic field of 50 kA / m is applied to the ferromagnetic film 83 and the ferromagnetic film 85, respectively, so that stable anti-ferromagnetic magnetization can be obtained even if the thickness of the non-magnetic film 84 is reduced. This is because the array can be realized. When the thickness of the non-magnetic layer (Cu) is reduced to less than 2 nm, the anti-parallel magnetization arrangement is destroyed and the resistance change rate is drastically reduced, unlike the conventional spin valve type magnetoresistive effect element. By applying a bias magnetic field in the direction to reduce the thickness of the non-magnetic film 84, the rate of resistance change can be significantly increased. (Embodiment 35) Next, the case where the number of ferromagnetic films having spin-dependent scattering ability is increased to three or more will be described.

As shown in FIG. 67, the base films 101 and F for controlling the orientation of the antiferromagnetic film 102 on the substrate 100.
5 to 50 nm thick antiferromagnetic film 102 made of eMn, NiO, PtMn, etc., 1 to 20 nm thick ferromagnetic film 103 made of CoFe, Co, NiFe, etc., 1 to 10 nm thick made of Cu, Au, etc. Non-magnetic film 104, thickness 1-20 nm
Ferromagnetic film 105, non-magnetic film 106 having a thickness of 1 to 10 nm,
Ferromagnetic film 107 having a thickness of 1 to 20 nm and thickness of 5 to 50
An antiferromagnetic film 108 having a thickness of nm was formed. Here, the ferromagnetic film 1
The film thicknesses of 03, 105 and 107 may be the same or different. Further, a protective film was formed thereon as needed to form the electrode terminal 109. The film formation was performed in a static magnetic field.

An exchange bias is applied in one direction from the antiferromagnetic films 102 and 108 to the ferromagnetic films 103 and 107 (x in the figure).
Direction). As a result, only the middle ferromagnetic film 105 has a high magnetic permeability, and the ferromagnetic films 103 and 107 have a low magnetic permeability, that is, a fixed magnetization. To fix the magnetization, a hard magnetic film 95 as shown in FIG. 63 may be used instead of the antiferromagnetic film. As a material of the ferromagnetic films 103 and 107 in contact with the antiferromagnetic films 102 and 108, Co having a high soft change rate but a high resistance change rate is used.
Ni, which uses CoFe or CoFe and has a good soft magnetism as the material of the intermediate ferromagnetic film 105, although the resistance change rate is not so high.
By using Fe, a high rate of resistance change can be realized in a low magnetic field.

With such a configuration, the intermediate ferromagnetic film 1
The magnetization rotation of No. 05 easily occurs in a low magnetic field, and the number of interfaces through the nonmagnetic layer is doubled as compared with the conventional spin valve structure film. A higher rate of resistance change can be realized. Further, since the ferromagnetic film, which is magnetized and rotated by the signal magnetic field, is located at the center of this laminated film, the disturbance of the magnetization of the ferromagnetic film due to the sense current magnetic field is slight, and stable signal detection is possible.
If the biasing method using the hard magnetic film or the demagnetizing field as described in Example 33 is used together, the angles formed by the magnetizations of the ferromagnetic films 103 and 107 and the intermediate ferromagnetic film 105 are antiparallel at the signal magnetic field 0. Can be As a result, the magnetoresistive effect element having higher sensitivity and lower noise can be obtained by the various effects described in the thirty-second embodiment. (Example 36) FIG. 68 shows a laminated film in which the number of ferromagnetic films having the spin-dependent scattering ability is increased to four.

Four layers of ferromagnetic films 112, 114, 116 and 118, which are laminated on the substrate 100 with the antiferromagnetic film 111 and the nonmagnetic layers 113, 115 and 117 interposed therebetween, and the antiferromagnetic film 1.
19 were sequentially formed, and the electrode terminal 109 was formed thereon so that the sense current could flow in the same direction as the signal magnetic field. An underlayer film for orientation control is formed below the antiferromagnetic film 111, and a protective film is formed above the antiferromagnetic film 119, if necessary. The material and film thickness of each film were the same as those shown in FIG.

At least during the film formation of the ferromagnetic film 112, a static magnetic field is applied in the x direction (track width direction) in the figure, while the static magnetic field direction is reversed by 180 ° during the subsequent film formation, and at least a repulsive force is applied. During the formation of the magnetic film 119, a static magnetic field was applied in the negative x direction in the figure. By the static magnetic field during this film formation,
Magnetization is fixed by the exchange bias magnetic field in the ferromagnetic film 112 in the x direction and in the ferromagnetic film 118 in the minus x direction. Further, in this configuration, when the track width is narrow, the widths of the ferromagnetic films 112, 114, 116 and 118 are also narrowed, so that a strong demagnetizing field is generated in that direction. This demagnetizing field causes the intermediate ferromagnetic film 114 not in contact with the antiferromagnetic film.
The magnetizations of and 116 are antiparallel to the magnetizations of the ferromagnetic films 112 and 118, respectively. That is, when the signal magnetic field is 0, the adjacent magnetizations of the four layers of ferromagnetic films are oriented antiparallel to each other.

When the demagnetizing field to the intermediate ferromagnetic films 114 and 116 is insufficient, the magnetic field generated by the sense current is in the minus x direction in the ferromagnetic films 112 and 114.
In the ferromagnetic films 116 and 118, it is desirable to apply the sense current in the y direction in the figure so that it is applied in the x direction. here,
If the exchange bias magnetic field from the antiferromagnetic film is set to be larger than the sense current magnetic field, the ferromagnetic films 112 and 1
The magnetization of 18 can be fixed in the exchange bias direction from the antiferromagnetic film without being disturbed by the current magnetic field.

With such a structure, the respective magnetization directions of the four layers of ferromagnetic films can be antiferromagnetically aligned at the signal magnetic field of zero. Therefore, ΔR /
R increases. Further, since the magnetization of each layer can be rotated by applying a slight signal magnetic field, it is possible to realize a magnetoresistive effect element using highly sensitive spin-dependent scattering. (Example 37) Next, a case in which the magnetizations of a part of the ferromagnetic films having the spin-dependent scattering ability are fixed and the magnetizations of the remaining ferromagnetic films are arranged in the signal magnetic field 0 in a direction different from the signal magnetic field direction explain.

FIG. 69 shows a laminated film in which the directions of the sense current and the signal magnetic field are orthogonal to each other. The non-magnetic film 12 is formed on the substrate 120.
Ferromagnetic film 1 having spin-dependent scattering ability with 2 interposed
A laminated film 21 and 123 and an antiferromagnetic film 124 were sequentially formed. The material and thickness of each film were the same as those shown in FIG. If necessary, an electrode terminal 125 was formed after forming a protective film on the antiferromagnetic film 124.

Here, at least during the formation of the ferromagnetic film 121, a static magnetic field is applied in the direction of the bisector of the x axis and the y axis in the figure, while at least the antiferromagnetic film 124 is formed. In some cases, the direction of the static magnetic field was rotated by 45 ° with respect to the former direction (y direction in the drawing). As a result, the ferromagnetic film 121
Magnetization of the ferromagnetic film 12 is applied in the x direction of the static magnetic field.
The magnetization of No. 3 was fixed in the signal magnetic field direction by the bias magnetic field from the antiferromagnetic film 124. According to such a configuration,
When the signal magnetic field is 0, the angle formed by the magnetizations of both ferromagnetic films becomes 45 °, and when the signal magnetic field is applied to the magnetization fixed direction of the ferromagnetic film 123, the magnetization directions of both ferromagnetic films become a ferromagnetic arrangement. When the resistance decreases and a signal magnetic field is applied in a direction different from the magnetization fixed direction by 180 °, the magnetization directions of both ferromagnetic films are antiferromagnetically arranged, so that the resistance increases. Therefore,
The operating point bias required for the conventional magnetoresistive effect element in order to realize the linear response becomes unnecessary. In this method, the magnetization of the ferromagnetic film 121 is easily inclined toward the y direction at the signal magnetic field 0 due to the ferromagnetic coupling between the ferromagnetic films 121 and 123, and the reproduced signal is easily distorted when a large signal magnetic field is applied. Tend. This is because the current magnetic field generated by the sense current is applied in the ferromagnetic film 121 in a direction different from this ferromagnetic coupling direction by 180 °, that is, the magnetic field and the current magnetic field due to this ferromagnetic coupling cancel each other out. This can be avoided by deciding the direction in which the sense current flows.

However, when a film having an anisotropic magnetoresistive effect is used as the ferromagnetic films 121 and 123, conversely, the magnetization M of the ferromagnetic film 121 is changed by the magnetic field due to this ferromagnetic coupling. If the magnetization is tilted in the M direction, the resistance change due to the magnetic anisotropy and the spin scattering will be superposed (because the current direction is the x direction), so that the sensitivity can be expected to be improved. Actually, it is necessary to adjust the magnetization direction of the ferromagnetic film 121 by means of current direction or the like depending on the situation where the magnetoresistive effect element is used.

By the way, in the thirty-seventh embodiment, it is necessary to apply a longitudinal bias magnetic field (a bias magnetic field in the direction of the bisector of the x-axis and the y-axis in the figure) necessary for suppressing Barkhausen noise. For this purpose, the antiferromagnetic film as shown in Example 32 is arranged on the substrate side of the ferromagnetic film 121 and exchange-coupled. Alternatively, as shown in FIG. 70A, a ferromagnetic film 126 having a good soft magnetism (Hc is smaller than the exchange bias magnetic field H _UA ) is laminated on the antiferromagnetic film 124, and at least the ferromagnetic film 126 is laminated. During the lamination of 126, the direction of the bias magnetic field during film formation is reversed by approximately 135 °, and the ferromagnetic film 126 is formed.
Is applied to the ferromagnetic film 121. In this case, since the film that is the spin-dependent scattering unit also serves as the base film, the exchange bias can be easily applied to the ferromagnetic film 126 formed on the antiferromagnetic film 124. As a result, the vertical bias magnetic field can be applied to the ferromagnetic film 121 by the magnetostatic coupling magnetic field (demagnetizing field) generated when actually processing the fine pattern suitable for the reproducing head, so that Barkhausen noise can be suppressed. .

In the embodiment of FIG. 70A, the antiferromagnetic film 1 is used.
Since the exchange bias direction is different on both sides of the film surface of 24,
The bias magnetic field direction may become uncertain. This is because, as shown in FIG. 70B, an extremely thin intermediate film 1 that weakens magnetic coupling with the antiferromagnetic film 124 in the middle but does not hinder crystal growth.
Antiferromagnetic film 12 through 24b (fcc phase film such as Cu)
It can be avoided by separating into 4a and 124c. At this time, as described in Example 32, it is preferable that the antiferromagnetic films 124a and 124c are made of materials having different Neel points or blocking temperatures in order to control the exchange bias magnetic field direction by heat treatment. Further, the ferromagnetic film 12
If 6 is thick and Bs is not high, a desired longitudinal bias magnetic field cannot be applied to the ferromagnetic film 121.
Since the sense current is shunted to 6, it is desirable that the ferromagnetic film has a high resistivity. Specifically, it is desirable to use a Co-based or Fe-based amorphous film or a nitrided or carbonized microcrystalline film. However, since such a film is difficult to exchange-couple with an antiferromagnetic film such as FeMn, the antiferromagnetic film 124a is formed.
An extremely thin ferromagnetic film 124b, such as NiFe or CoFeTa, which is easily exchange-coupled is laminated on the portion in contact with, and a high resistance amorphous high Bs ferromagnetic film 126a is laminated thereon so as to be ferromagnetic exchange-coupled. Is desirable. (Embodiment 38) FIG. 70C shows a laminated film in which the directions of the sense current and the signal magnetic field are parallel. The configuration is the same as that of FIG. 69 except that the sense current flows in a different direction, the magnetization of the ferromagnetic film 121 is applied in the x direction in the drawing, and the longitudinal direction of the film is rotated by 90 °. In this configuration, when the signal magnetic field is 0, the angle formed by the magnetizations of both ferromagnetic films is 90 °, and when the signal magnetic field is applied in the magnetization fixed direction of the ferromagnetic film 123, the magnetizations of both ferromagnetic films are arranged in a ferromagnetic arrangement. Therefore, the resistance decreases, and conversely, when a signal magnetic field is applied in a direction different from the magnetization fixed direction by 180 °, the magnetizations of both ferromagnetic films are antiferromagnetically arranged, and the resistance increases. Therefore, the operating point bias becomes unnecessary. In this configuration, the current magnetic field due to the sense current is in the easy axis direction of the ferromagnetic film 121, and this magnetic field has an effect of suppressing Barkhausen noise.

Furthermore, in Example 38, the ferromagnetic film 123 was used.
The ferromagnetic film 12 due to the ferro-coupling magnetic field that is easily generated from
It should be added that the magnetization of No. 1 easily tilts in the y direction.
As described in detail in Example 37, this ferromagnetic coupling magnetic field has the advantage of superimposing the anisotropic magnetoresistive effect although the signal magnetic field dynamic range is narrowed. Since the current magnetic field is applied to the ferromagnetic film 121, the ferromagnetic film 1 is not always required.
The 21 easy axes need not be in the x direction.

When the Barkhausen noise suppression effect is insufficient, the magnetization fixed direction of the ferromagnetic film 123 is deviated from the signal magnetic field direction, so that a magnetostatic coupling magnetic field is generated in the x direction in the figure to generate stronger Barkhausen noise. A suppressing magnetic field can be applied. (Example 39) FIG. 71 shows a laminated film in which three ferromagnetic films having spin-dependent scattering ability are formed. FIG. 71 shows a case where the sense current and the signal magnetic field are orthogonal to each other. An antiferromagnetic film 137 and a laminated film of ferromagnetic films 132, 134 and 136 having a spin-dependent scattering ability with an antiferromagnetic film 131 and nonmagnetic films 133 and 135 interposed in a static magnetic field are sequentially formed on a substrate 130. Formed. The electrode terminal 138 was formed on it.

Here, the direction of the static magnetic field is at least the same direction during the formation of the ferromagnetic film 132 and the antiferromagnetic film 137 (the y direction in the drawing), and is 4 when the ferromagnetic film 134 is formed.
Direction that forms an angle of 5 ° (the direction of the bisector of the x-axis and the y-axis in the figure)
And As a result, the magnetizations of the ferromagnetic films 132 and 136 are fixed in the y direction in the drawing, the magnetization of the ferromagnetic film 134 maintains a high magnetic permeability, and at a magnetic field of 0, in the vicinity of the bisector of the x axis and the y axis in the drawing. Suitable for. Therefore, even in this configuration, when the magnetic field is 0, the angle formed by the magnetizations of both ferromagnetic films is approximately 45 °, and when the signal magnetic field is applied to the magnetization fixed direction of the ferromagnetic film 136, the magnetization directions of both ferromagnetic films become ferromagnetic. Resistance is reduced because it becomes a regular arrangement,
Conversely, when a signal magnetic field is applied in a direction different from the magnetization fixed direction by 180 °, the magnetization directions of both ferromagnetic films are antiferromagnetically arrayed, and the resistance increases. That is, the operating point bias becomes unnecessary. With this configuration, the number of interfaces is doubled, and thus the sensitivity is also improved. (Example 40) The resistance-magnetic field characteristics of the laminated film of the magnetoresistive effect element of the method shown in Example 38 will be described.

In FIG. 70C, a sapphire C-plane substrate is used as the substrate 120, a Co ₉₀ Fe ₁₀ film having a thickness of 6 nm having a Pd base film having a thickness of 5 nm is used as the ferromagnetic film 121, and the nonmagnetic film 122 is used. A 3 nm thick Cu film is used as
A Co ₉₀ Fe ₁₀ film having a thickness of 4 nm is used as the ferromagnetic film 123, a FeMn film having a thickness of 15 nm is used as the antiferromagnetic film 124, and a P film having a thickness of 5 nm is used as a protective film thereon.
A d film was formed.

This laminated film was collectively formed by a two-pole sputtering method while maintaining a vacuum. In addition, a static magnetic field is applied by a permanent magnet during film formation, and after the ferromagnetic film 121 is formed, the direction of the static magnetic field is reversed by 90 °, and the angle formed by the easy axes of the ferromagnetic films 121 and 123 is changed. Was 90 °. In addition, the preliminary exhaust of sputtering is 1 × 10 ⁻⁴ Pa or less,
The sputtering gas pressure was 0.4 Pa.

The resistance-magnetic field characteristics of this laminated film are shown in Example 33.
It measured similarly to. FIG. 72 shows resistance-magnetic field characteristics in the hard axis direction. In FIG. 72, the resistance in the ferromagnetic magnetization arrangement is standardized as 1. As can be seen from FIG. 72, when the signal magnetic field is 0, the magnetic field change of the resistance having good linearity can be obtained. This shows that the operating point bias is unnecessary. (Example 41) In this example, two or more layers of another ferromagnetic film or antiferromagnetic film are laminated on both ferromagnetic films of a spin-dependent scattering unit composed of a ferromagnetic film / a non-magnetic film / a ferromagnetic film. An example of a magnetoresistive effect element in which both bias magnetic fields generated at this time are made substantially orthogonal is shown.

FIG. 73 shows a high-Hk ferromagnetic film (for example, Hk to 5 kA) having a hard ferromagnetic film such as CoPt and a uniaxial magnetic anisotropic magnetic field Hk larger than those of the spin-dependent scattering unit on the substrate 120. / M CoFeRe film, etc.) or N
A first bias film 121a for applying a bias magnetic field composed of an antiferromagnetic film such as iO, a spin-dependent scattering unit (ferromagnetic film 121, nonmagnetic film 122, ferromagnetic film 12).
3) shows a multilayer film in which second bias films 124 for applying a bias magnetic field made of an antiferromagnetic film such as FeMn are sequentially laminated. The first bias film 121a of this multilayer film
The bias magnetic field generated from the magnetic field is mainly applied to the ferromagnetic film 121 by exchange coupling through the laminated interface.
On the other hand, the bias magnetic field generated from the second bias film 124 is mainly due to the exchange coupling through the stacking interface and is mainly due to the ferromagnetic film 1.
Join 23. The first and second bias magnetic fields are applied so as to satisfy a directional relationship that is substantially orthogonal. Further, the second bias magnetic field has a strong value such that the magnetization of the ferromagnetic film 123 cannot be substantially moved by the signal magnetic field (10 kA).
/ M or more is desirable).

On the other hand, the first bias magnetic field strength is set to such a level that the magnetization of the ferromagnetic film 121 can be rotated by the signal magnetic field and Barkhausen noise can be suppressed. Specifically, when an antiferromagnetic film is used for the first bias film,
It is desirable that the bias magnetic fields of the bias film 121a and the ferromagnetic film 121 be 5 kA / m or less. When a ferromagnetic film is used as the first bias film, the bias film 121a is kept in a constant direction by some means to form a single magnetic domain, and the bias film 121a and the ferromagnetic film 121 are strongly exchange-coupled. When integrated, the bias field 12 is generated by the signal magnetic field.
Since 1a and the ferromagnetic film 121 can rotate in substantially the same manner and the ferromagnetic film 121a has a single magnetic domain, the ferromagnetic film 121 also has a single magnetic domain and Barkhausen noise can be removed. Alternatively, for example, another layer may be inserted at the interface to form the bias film 121a.
There is also a method of weakening the exchange coupling of the ferromagnetic film 121 to less than 5 kA / m. In this case, since only the ferromagnetic film 121 is magnetized and rotated by the signal magnetic field, it is preferable to suppress the magnetic permeability of the bias film 121a to make the magnetization hard to move. Examples of the magnetic permeability suppressing means include improvement of Hk, improvement of coercive force, and application of a unidirectional bias magnetic field to the bias film 121a by some means.

Here, as a means for making the ferromagnetic film 121a into a single magnetic domain, as shown in FIG.
a is made longer than the spin valve unit, and the bias film 1
A new antiferromagnetic film or hard film 121 is formed on the edge of 21a.
It is possible to stack b.

When the magnetoresistive effect element having the above structure is manufactured, the magnetization direction of the ferromagnetic film 123 is fixed and the ferromagnetic film 12 is fixed.
Since the magnetization of No. 1 changes according to the signal magnetic field, a high-sensitivity magnetoresistive effect element having good linearity can be obtained with the signal magnetic field of ~ 0 similarly to the embodiment shown in FIG. 69, and the signal magnetic field is detected. Since the domain wall of the ferromagnetic film 121 can also be removed, the operating point bias is unnecessary, and the signal magnetic field reproduction with high sensitivity and noise can be performed.

Here, the easy axis of magnetization of the ferromagnetic film 121 may be applied in a direction orthogonal to the bias magnetic field direction.
This is particularly desirable when a Co-based ferromagnetic film having a large magnetic anisotropy is used for 121. Then, the saturation magnetic field corresponding to the anisotropic magnetic field and the bias magnetic field can be canceled out, so that Hs can be significantly reduced, so that the slope of the saturation magnetic field-resistance characteristic shown in FIG. As compared with the case where the easy axis of magnetization of the ferromagnetic film 121 is in the same direction, it is possible to detect the signal magnetic field with higher sensitivity. To change the bias magnetic field and the direction of the easy axis of the ferromagnetic film, the direction of the magnetic field applied during the formation of the bias film 121a and the ferromagnetic film 1
There is a method of changing the magnetic field application direction during the film formation of 21. (Example 42) As shown in FIG. 75, a C film having a thickness of 20 nm for controlling the orientation of a high coercive force film is formed on a supporting substrate 140.
r Underlayer film 141, high coercive force film 142 made of Co or the like having a thickness of 8 nm, nonmagnetic film 143 made of Cu or the like and having a thickness of 3 nm, and ferromagnetic film 144 made of NiFe or the like and having a thickness of 4.6 nm.
Were sequentially formed, and an electrode terminal 145 was further formed thereon to manufacture a magnetoresistive effect element having a spin valve structure.
The laminated film was formed by ultra-high vacuum E gun vapor deposition. At this time, the substrate temperature was set to about 100 ° C., and the inside of the vacuum chamber was evacuated to 1 × 10 ⁻⁸ Pa or less.

Co / C when the substrate temperature is about 100 ° C.
The X-ray diffraction pattern of the r film was examined. The result is shown in FIG. As shown in FIG. 76, this film contains Cr (20
0) had a high orientation, and the Co film using this Cr film as a base film also had a high orientation (110). Note that Co (110)
The rocking curve half-width of the peak was about 3 °. Next, the NiF film shown in FIG. 75 was formed at a substrate temperature of about 100 ° C.
FIG. 77 shows an RH curve in the hard axis direction of a laminated film having a structure of e / Cu / Co / Cr / substrate. The RH curve was created based on the value measured by the four-terminal method after processing the laminated film into a pattern of 2 mm × 6 μm using a normal resist process and ion milling. At this time, the easy axis was in the pattern longitudinal direction and the magnetic field was applied in the pattern width direction.

As shown in FIG. 77, when the applied magnetic field is ± 80 Oe, the resistance change rate is about 6.5%, and the saturation magnetic field is about 3.
It became 6 kA / m.

In this structure, Hc of the high coercive force film is about 8 kA.
/ M, so no problem occurs when the magnetic field from the medium is less than 8 kA / m, but for a structure in which the head and the medium are close to each other, that is, a structure in which the magnetic field from the medium is 8 kA / m or more Not suitable. Therefore, a laminated film was formed with the same structure and film thickness as in FIG. 75 at a substrate temperature of about 200 ° C. and in a magnetic field of about 8 kA / m.

Co / C when the substrate temperature is about 200 ° C.
The X-ray diffraction pattern of r was almost the same as in FIG. The half-width of the rocking curve of the Co (110) peak was about 3 ° in this laminated film as well. Furthermore, when measured with a pole figure, a bias of the hexagonal C-axis was observed in the magnetic field direction. Therefore, single crystal-like Co was obtained as compared with the laminated film formed in the absence of a magnetic field at a substrate temperature of 100 ° C.

Next, R in the direction of the hard axis of the laminated film having the same structure as that shown in FIG. 75 formed in a magnetic field at a substrate temperature of about 200 ° C.
The -H curve is shown in FIG. 78. The RH curve was created based on the value measured by the 4-terminal method by processing the laminated film into a pattern of 2 mm × 6 μm as described above. At this time, the easy axis (C
The axial direction) was the longitudinal direction of the pattern, and the magnetic field was applied in the pattern width direction.

As shown in FIG. 78, the external magnetic field ± 1.6 k
Even in the case of A / m, the magnetization of the high coercive force film hardly moved by the applied magnetic field, and the saturation magnetic field of the NiFe film could be kept as low as about 2.8 kA / m. The rate of change in resistance was about 7.5%.

The laminated film having the above structure has an external magnetic field of 1.6 kA.
/ M, the magnetization of the high coercive force film is stable.
A pattern was prepared in which the easy axis of the e film was the width direction and the C axis of Co was substantially the longitudinal direction. This configuration eliminates the need for operating point bias. At this time, a magnetic field was applied in the longitudinal direction of the pattern, and the RH curve at that time was measured. In addition,
The pattern shape was 2 mm × 6 μm as described above. The result is shown in FIG. 79. As can be seen from FIG. 79, a good RH curve without hysteresis was obtained, and Hk was a low value of about 1.6 kA / m.

Although the Co film is used as the high coercive force film here, a CoNi film or a CoCr film may be used. Further, as the base film, a W film or the like may be used in addition to the Cr film, and based on these Cr and W, an additive element may be added thereto. This underlayer film can be applied to a so-called hard film underlayer film throughout the present invention. This allows the C-axis to exist within the film surface of the hard magnetic film (the C-axis is aligned in a specific direction). Therefore,
When the hard magnetic film is fixed, it is possible to prevent the ferromagnetic film formed thereon from being fixed.

For reference, the MH curve of the laminated film having no underlying film is shown in FIG. It can be seen that the leakage magnetic field is generated from the perpendicular component of the magnetization of Co and deteriorates the soft magnetic characteristics of the NiFe film. This is a part of NiFe and C
It is considered that the magnetization of o is integrated. (Example 43) As shown in Example 42, the substrate temperature was about 2
Since the high coercive force film formed at 00 ° C. is a single crystal-like film and has low resistance, the mean free path of electrons can be made sufficiently longer than the thickness of the high coercive force film. Therefore, as shown in FIG. 81, the high coercive force film 142 and the ferromagnetic film 144 are connected to the Cu non-magnetic film 14.
Laminated through 3. The resistance change rate of this laminated film is about 15
%, Which was a high value. In order to manufacture a laminated film having such a structure, it is desirable to provide a base film for controlling the orientation of the high coercive force film 142 of the first layer. Also,
In this example, a Cr film 141 having a thickness of 20 nm was used as the base film. (Embodiment 44) Next, the case where the high coercive force control film for orientation control is used as the bias film in Embodiment 34 will be explained.

In this example, as shown in FIG. 82, a magnetoresistive effect element having a spin valve structure was formed on the orientation controlling high coercive force film 142 with a magnetic insulating layer 146 interposed therebetween. As described above, by using the orientation control high coercive force film 142, the high coercive force film 142 and the NiFe film 1 are formed at the film end portions.
44 is magnetostatically coupled, and the domain wall at the end of the NiFe film, which causes Barkhausen noise, can be fixed. Furthermore, since the orientation control high coercive force film is used, it is possible to avoid the influence of the high coercive force film on the NiFe film, for example, the leakage magnetic field inside the film, and to manufacture a good element without degrading the soft magnetic characteristics of the NiFe film. it can. Further, here, an antiferromagnetic film or the like may be used as the exchange bias film of the spin valve structure.

[0268]

As described above, the magnetoresistive effect element of the present invention can exhibit a high rate of resistance change and excellent soft magnetic characteristics at the same time, and its industrial value is great.

[Brief description of drawings]

FIG. 1 is a sectional view showing a magnetoresistive effect element (spin valve structure) of a first invention of the present invention.

FIG. 2 is a graph showing the external magnetic field dependence of the resistance change rate of the magnetoresistive effect element shown in FIG.

FIG. 3 is a graph showing a magnetization curve of the magnetoresistive effect element shown in FIG.

FIG. 4 is a sectional view showing an example of a magnetoresistive effect element (artificial lattice film) of the first invention of the present invention.

5 is a graph showing the external magnetic field dependence of the resistance change rate of the magnetoresistive effect element shown in FIG.

FIG. 6 is a graph showing the film thickness dependence of coercive force when a Cu ₉₀ Fe ₁₀ Cu underlayer is present.

FIG. 7 is a graph showing the film thickness dependence of the coercive force of a Co ₉₀ Fe ₁₀ film without a Cu underlayer.

FIG. 8 is a cross-sectional view showing a magnetoresistive effect element (spin valve structure) of the first invention of the present invention.

FIG. 9A is θ-2θ on the C plane of the sapphire substrate.
Scan X-ray diffraction curve, (B) is a θ-2θ scan X-ray diffraction curve on the R surface of the sapphire substrate.

FIG. 10: Co ₉₀ Fe ₁₀ film / Cu film / sapphire substrate C
Rocking curve for the densest surface peak in the plane.

FIG. 11 is a graph showing the dependence of the coercive force of the Co ₉₀ Fe ₁₀ film on the half-width of the rocking curve in the close-packed surface reflection.

FIG. 12 is a graph showing Al concentration x dependence of coercive force in a (Co ₉₀ Fe ₁₀ ) _1-x Al _x film / Cu film.

FIG. 13 is a graph showing the close-packed surface reflection intensity dependence of the coercive force of a Co ₉₀ Fe ₁₀ film / Cu film.

FIG. 14 is a graph showing the dependence of coercive force on a (Co ₉₀ Fe ₁₀ ) _1-x Ta _x film / Cu film in Ta concentration x.

FIG. 15 is a sectional view showing the magnetoresistive effect element (spin valve structure) of the first invention of the present invention.

FIG. 16 is a sectional view showing a magnetoresistive effect element according to a third aspect of the present invention.

17 is an MH curve in the easy axis direction of the magnetoresistive effect element shown in FIG.

FIG. 18 is an MH curve in the hard axis direction of the magnetoresistive effect element shown in FIG. 16;

19 is an RH curve of the magnetoresistive effect element shown in FIG.

FIG. 20 is an MH curve in the easy axis direction of a magnetoresistive effect element in which a high resistance amorphous layer is not provided.

FIG. 21 is a MH curve in the hard axis direction of a magnetoresistive effect element having no high-resistance amorphous layer.

FIG. 22 is a sectional view showing a magnetoresistive effect element according to a third invention of the present invention.

23A to 23C are cross-sectional views showing a manufacturing process of another example of the magnetoresistive effect element of the third invention of the present invention.

FIG. 24 is a perspective view showing another example of the magnetoresistive effect element according to the third aspect of the present invention.

FIG. 25 is a sectional view showing an example of a magnetoresistive effect element according to a fourth aspect of the present invention.

FIG. 26 shows Δρ in the magnetoresistive effect element shown in FIG.
/ [Rho ₀ and graphs showing the relationship between d _CoFe.

FIG. 27 is a sectional view showing a magnetoresistive effect element according to a fifth aspect of the present invention.

FIG. 28 is a sectional view showing a magnetoresistive effect element according to a fifth aspect of the present invention.

FIG. 29 is a graph showing the dependence of coercive force on the thickness of a ferromagnetic film in the magnetoresistive effect element according to the sixth aspect of the present invention.

FIG. 30 is a graph showing the dependence of coercive force on the thickness of a ferromagnetic film in the magnetoresistive effect element according to the sixth aspect of the present invention.

FIG. 31 is a magnetization curve of a ferromagnetic film of the magnetoresistive effect element according to the sixth aspect of the present invention.

FIG. 32 is a graph showing the stacking period dependency in the magnetoresistive effect element according to the seventh aspect of the present invention.

FIG. 33 is a graph showing the relationship between the saturation magnetic field Hs and the Cu film thickness in the ferromagnetic film of the magnetoresistive effect element of the sixth invention of the present invention.

FIG. 34 is a magnetization curve of a ferromagnetic film of the magnetoresistive effect element of the seventh invention of the present invention.

FIG. 35 is a sectional view showing a magnetoresistive effect element of a seventh invention of the present invention.

FIG. 36 is a cross-sectional view showing an interface state between Cu and CoFe in the seventh invention.

FIG. 37 is a magnetization curve of the magnetoresistive effect element shown in FIG. 35.

38 is a graph showing resistance change characteristics of the magnetoresistive effect element shown in FIG. 35.

FIG. 39 is a magnetization curve of a conventional magnetoresistive effect element.

FIG. 40 is a graph showing resistance change characteristics of a conventional magnetoresistive effect element.

FIG. 41 is a magnetoresistive element C of the seventh invention of the present invention.
u Magnetization curve for a ferromagnetic film with an underlayer.

FIG. 42 is a magnetoresistive effect element C of the seventh invention of the present invention.
5 is a graph showing resistance change characteristics of a ferromagnetic film having a u underlayer film.

FIG. 43 is a sectional view showing a magnetoresistive effect element according to a fourth aspect of the present invention.

FIG. 44 is a magnetization curve of the magnetoresistive effect element shown in FIG. 43.

45 is a graph showing resistance change characteristics of the magnetoresistive effect element shown in FIG. 43.

FIG. 46 is a schematic diagram for explaining fluctuations in the film.

FIG. 47 (A) is Co ₉₀ F on a MgO (110) plane substrate.
X-ray diffraction curve of small-angle reflection of e ₁₀ / Cu artificial lattice film,
(B) is Co ₉₀ Fe ₁₀ / Cu on MgO (110) substrate
X-ray diffraction curve of the medium angle reflection of the artificial lattice film.

FIG. 48 (A) is a rocking curve measured from the [110] axis direction with respect to the fcc (220) reflection in FIG. 47, and (B) is a rocking curve measured from the [100] axis direction with respect to the fcc (220) reflection in FIG. 47. curve.

49A is a schematic diagram showing an in-plane distribution of a normal line of a crystal orientation plane due to fluctuation of the crystal orientation plane, and FIG. 49B is a schematic diagram showing a sense current direction dependency of a resistance change rate.

FIG. 50 (A) shows Cu 5.5 nm / (Cu 1.1 nm / C
oFe1nm) ₁₆ artificial lattice film magnetization curve in the direction of the external magnetic field [100] axis, (B) Cu5.5nm / (Cu1.1nm /
CoFe1 nm) ₁₆ Magnetization curve in the direction of the external magnetic field [110] axis of the artificial lattice film.

FIG. 51 shows Co ₉₀ F on a MgO (110) plane substrate.
graph showing the bias voltage dependence of the resistance change rate of the e ₁₀ / Cu laminated film.

FIG. 52 is an Fcc phase (111) -oriented Co ₉₀ Fe ₁₀
6 is a conceptual diagram when a stacking fault is introduced into the / Cu stacked film.

FIG. 53 shows Co ₉₀ Fe ₁₀ oriented in the (111) plane in the fcc phase.
6 is a conceptual diagram showing an atomic arrangement when a stacking fault is introduced into a / Cu stacked film.

FIG. 54: Co ₉₀ Fe ₁₀ oriented in the (111) plane in the fcc phase
FIG. 6 is a conceptual diagram showing an atomic arrangement in the case where twin defects are introduced into the / Cu laminated film.

55 is a schematic diagram showing the sense current direction dependence of the resistance change rate in the state shown in FIG. 54.

FIG. 56 is a graph showing the substrate bias dependency of the resistance change rate of the Co ₉₀ Fe ₁₀ / Cu artificial lattice film on the glass substrate.

FIG. 57 is a graph showing the bias dependence of the long-period structure reflection intensity of a Co ₉₀ Fe ₁₀ / Cu artificial lattice film on a glass substrate.

FIG. 58 is a graph showing the bias dependence of the fcc phase (111) plane reflection intensity of a Co ₉₀ Fe ₁₀ / Cu artificial lattice film on a glass substrate.

FIG. 59 is a graph showing the bias dependence of the coercive force of the Co ₉₀ Fe ₁₀ / Cu artificial lattice film on the glass substrate.

FIG. 60 is a perspective view showing a magnetoresistive effect element of an eighth invention of the present invention.

FIG. 61 is a perspective view showing a magnetoresistive effect element according to an eighth aspect of the present invention.

FIG. 62 is a perspective view showing a magnetoresistive effect element of an eighth invention of the present invention.

FIG. 63 is a perspective view showing a magnetoresistive effect element according to an eighth aspect of the present invention.

FIG. 64 is a perspective view showing a magnetoresistive effect element according to an eighth invention of the present invention.

FIG. 65 is a perspective view showing a magnetoresistive effect element of an eighth invention of the present invention.

FIG. 66 is a graph showing resistance change characteristics of the magnetoresistive effect element according to the eighth aspect of the present invention.

FIG. 67 is a perspective view showing a magnetoresistive effect element according to a twelfth invention of the present invention.

FIG. 68 is a perspective view showing a magnetoresistive effect element according to a twelfth invention of the present invention.

FIG. 69 is a perspective view showing a magnetoresistive effect element of the tenth invention of the present invention.

70 (A) to (C) are perspective views showing a magnetoresistive effect element of a tenth invention of the present invention.

FIG. 71 is a perspective view showing a magnetoresistive effect element according to a tenth aspect of the present invention.

FIG. 72 is a graph showing resistance change characteristics of laminated films of the magnetoresistive effect element according to the tenth aspect of the present invention.

FIG. 73 is a perspective view showing a magnetoresistive effect element according to a twelfth invention of the present invention.

FIG. 74 is a sectional view showing a magnetoresistive effect element of a twelfth invention of the present invention.

FIG. 75 is a sectional view showing a magnetoresistive effect element of the thirteenth invention of the present invention.

FIG. 76 is an X-ray diffraction pattern of a Co / Cr laminated film.

FIG. 77 is a first example of the present invention formed at a substrate temperature of about 100 ° C.
The RH curve of the laminated film of 3 invention.

FIG. 78 is a first example of the present invention formed at a substrate temperature of about 200 ° C.
The RH curve of the laminated film of 3 invention.

FIG. 79 is an RH curve of the laminated film of the thirteenth invention when the pattern width direction is taken as the easy axis.

FIG. 80 is an RH curve of the laminated film of the thirteenth invention of the present invention in the case where a base film is not provided.

FIG. 81 is a sectional view showing a magnetoresistive effect element of the thirteenth invention of the present invention.

FIG. 82 is a sectional view showing a magnetoresistive effect element of the thirteenth invention of the present invention.

FIG. 83 is a perspective view showing a conventional magnetoresistive effect element.

FIG. 84 is an RH curve of a conventional magnetoresistive effect element.

[Explanation of symbols]

10, 20 ... Sapphire substrate 11, 21, 71 ... Co
₉₀ Fe ₁₀ film, 12, 22, 23, 70 ... Cu film, 13 ...
FeMn film, 14 ... Ti film, 15, 24 ... Cu lead,
26 ... Ni oxide film, 30, 41, 140 ... Support substrate,
31, 46 ... High resistance amorphous layer, 32, 44, 8
3,85,91,93,103,105,107,11
2,114,116,118,121,123,13
2, 134, 136, 144 ... Ferromagnetic film, 33, 45,
143 ... Intermediate layer, 34 ... Exchange bias layer, 35, 47 ...
Lead, 42 ... CoPtCr film, 43 ... Resist, 5
0, 80, 90, 100, 120, 130 ... Substrate, 51
... Ferromagnetic stacking unit, 52, 84, 87, 88, 92, 1
04, 106, 113, 115, 117, 122, 13
3,135,163 ... Non-magnetic film, 53, 82, 94, 1
02, 108, 111, 119, 124, 131, 13
7, 165 ... Antiferromagnetic film, 54, 166 ... Protective film, 5
5, 62, 86, 96, 109, 125, 145 ... Electrode terminal, 60 ... MgO substrate, 61 ... Laminated film, 81, 10
1, 141 ... Base film, 95 ... Hard magnetic film, 97 ... Insulating film, 142 ... High coercive force film, 146 ... Magnetic insulating layer, 16
0 ... Thermally oxidized Si substrate, 161 ... High resistance ferromagnetic film, 162
... first ferromagnetic film, 164 ... second ferromagnetic film, 167
a, 167b ... Electrodes, 169 ... High resistance antiferromagnetic films.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (31) Priority claim number Japanese Patent Application No. 5-53612 (32) Priority date Hei 5 (1993) March 15 (33) Priority claim country Japan (JP) (72) Inventor Susumu Hashimoto 1 Komukai Toshiba-cho, Kawasaki-shi, Kanagawa Prefectural R & D Center, Toshiba Corporation (72) Inventor Atsushi Sawana 1 Komukai-shiba Cho, Saiwai-ku, Kawasaki, Kanagawa Shiba Research & Development Center ( 72) Inventor Yuzo Kamiguchi 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Within the Toshiba Research and Development Center (72) Inventor Masaji Sahashi 1 Komukai-Toshiba, Ko-ku, Kawasaki-shi, Kanagawa Toshiba Corporation R & D Center

Claims (12)

[Claims] 1. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially laminated on a substrate, wherein the two ferromagnetic films are uncoupled. And at least one of the ferromagnetic films is Co, F
A magnetoresistive effect element characterized in that at least one element selected from the group consisting of e and Ni is contained as a main component, and the closest packed surface is oriented in the direction perpendicular to the film surface. 2. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a nonmagnetic film and a ferromagnetic film are sequentially laminated on a substrate, wherein at least one of the ferromagnetic films is Co, Pd, Al, C containing at least two elements selected from the group consisting of Fe and Ni as main components
u, Ta, In, B, Nb, Hf, Mo, W, Re, R
A magnetoresistive element having a composition containing at least one element selected from the group consisting of u, Rh, Ga, Zr, Ir, Au, and Ag. 3. A (n + 1) layer ferromagnetic film and n are formed on a substrate.
A magnetoresistive effect element comprising a laminated film (where n represents an integer of 1 to 4) in which non-magnetic films of layers are alternately formed, wherein the uppermost layer and the lowermost layer of the laminated film are strong. A magnetoresistive effect element, characterized in that a ferromagnetic film having a resistivity of 50 μΩcm or more is further laminated to be adjacent to at least one of the magnetic films. 4. A (n + 1) layer ferromagnetic film and n are formed on a substrate.
A magnetoresistive effect element comprising a laminated film (where n is an integer of 1 to 4) in which first nonmagnetic films of layers are alternately formed, wherein the uppermost layer and the uppermost layer of the laminated film are At least one of the lower ferromagnetic films has a thickness of 5 nm or less,
A magnetoresistive effect element characterized in that a second non-magnetic film having a resistivity not more than twice that of the ferromagnetic film is further formed adjacent to the ferromagnetic film having a thickness of 5 nm or less. 5. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film and a ferromagnetic film are sequentially laminated on a substrate, the uppermost layer and the lowermost layer of the laminated film. A magnetoresistive effect element, characterized in that a thin film having a higher resistivity and a longer mean free path than that of the ferromagnetic film is further formed adjacently to at least one of the ferromagnetic films. 6. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially laminated on a substrate, wherein the bottommost ferromagnetic layer of the laminated film is ferromagnetic. A magnetoresistive effect element, wherein the film is made of a CoFe alloy, and an underlayer film having an fcc phase having a larger lattice constant than that of the CoFe alloy is further formed adjacent to the ferromagnetic film. 7. A magnetoresistive element comprising at least one ferromagnetic film, a first non-magnetic film, and a ferromagnetic film, which are sequentially laminated on a substrate, wherein at least one ferromagnetic film. A second non-magnetic film and a ferromagnetic film having a thickness different from that of the first non-magnetic film are alternately formed adjacent to the main surface opposite to the first non-magnetic film, A magnetoresistive effect element characterized in that the magnetizations of the respective ferromagnetic films in a unit laminated film composed of these ferromagnetic films and the second ferromagnetic film are ferromagnetically coupled to each other. 8. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially laminated on a substrate, wherein at least one of the ferromagnetic films is biased. A bias film formed adjacent to or close to the laminated film as a magnetic field applying means, and
A bias magnetic field is applied to the two ferromagnetic films so that the components in the track width direction are antiparallel to each other.
A magnetoresistive effect element characterized in that the magnetizations of the two ferromagnetic films rotate in mutually opposite directions by a signal magnetic field. 9. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film are sequentially laminated on a substrate, wherein each of the two ferromagnetic films is a signal. When the magnetic field is zero, the magnetization fixed film that substantially retains the magnetization direction thereof and the magnetic field detection film that detects the signal magnetic field by changing the magnetization due to the signal magnetic field are used as the two ferromagnetic layers. A magnetoresistive effect element, wherein the magnetization directions of the films are substantially orthogonal to each other, and a sense current is passed in a signal magnetic field direction. 10. A magnetoresistive element comprising at least a ferromagnetic film, a non-magnetic film, and a ferromagnetic film, which are sequentially stacked on a substrate, wherein each of the two ferromagnetic films is a signal. A magnetization pinned film whose magnetization direction is substantially maintained even when a magnetic field is applied, and a magnetic field detection film which detects the signal magnetic field by changing its magnetization direction by the signal magnetic field. A magnetoresistive effect element characterized in that an angle θ formed by a magnetization direction of a ferromagnetic film is 30 ° or more and 60 ° or less. 11. A magnetoresistive effect element comprising a laminated film in which at least a ferromagnetic film, a nonmagnetic film, and a ferromagnetic film are sequentially laminated on a substrate, wherein a bias to the two ferromagnetic films is provided. A magnetoresistive effect element comprising a bias film of two or more layers laminated as a magnetic field applying means adjacent to or in proximity to the laminated film. 12. A magnetoresistive device comprising a high coercive force film having a hexagonal C-axis in the film plane and a ferromagnetic film having a coercive force lower than that of the high coercive force film on a substrate. Effect element.