JPH08330134A - Magnetoresistance effect laminated film and its manufacture - Google Patents

Abstract

PURPOSE: To provide a magnetoresistance effect laminated film exhibiting large magnetoresistance change rate at a small applied magnetic field by laminating a two-layer film formed of another (nonmagnetic metal film and ferromagnetic metal film) having specific value or less of boundary magnetic anisotropy on the two-layer film formed of (nonmagnetic metal film and ferromagnetic metal film). CONSTITUTION: The magnetoresistance effect laminated film comprises a thin film made of a nonmagnetic metal film and a ferromagnetic metal film in the order of (nonmagnetic metal film and ferromagnetic metal film) and (nonmagnetic metal film and ferromagnetic metal film) i [i is repetition number of 1 of two or more of (nonmagnetic metal film and ferromagnetic metal film), wherein the boundary magnetic anisotropy of the two-layer film formed of two (nonmagnetic metal and ferromagnetic metal films) of the board side is larger, and the difference of the two boundary magnetic anisotropy is 0.1erg/cm<2> or more. A method for manufacturing it comprises the step of forming Cu leads 21 on a 5 layer films sequentially laminated with a Pt film 1, a Co film 2, a Cu film 3, a Co film 4 and a Cu film 5 on a glass board 11.

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 sensor, a magnetic head, a magnetoresistive memory and the like, and more particularly to a magnetoresistive effect laminated film using a laminated body of a ferromagnetic thin film and a non-magnetic thin film.

[0002]

2. Description of the Related Art The phenomenon in which the electrical resistance of a substance changes with the application of an external magnetic field is called the magnetoresistive effect (MR effect). This magnetoresistive effect is applied to magnetoresistive elements such as magnetic sensors, magnetic heads, and magnetoresistive memories. Generally, for these applications, a large magnetoresistance change rate (ΔR / R) is exhibited even at a small applied magnetic field at room temperature, high magnetic field sensitivity is exhibited, and a magnetoresistive effect curve within an operating magnetic field range
Small hysteresis is required.

The magnetoresistive effect of a ferromagnetic material is the anisotropic magnetoresistive effect (AMR) in which the electric resistance changes depending on the angle formed by the magnetization direction and the current direction.
Ni-Co alloys have been used conventionally. The resistance of these changes with a small magnetic field, but ΔR / R is as small as 2 to 4%, and the output when used as an element is also small.

On the other hand, in recent years, a structure in which a non-ferromagnetic metal layer is sandwiched by a ferromagnetic metal layer by using a thin film technique has a large ΔR / R independent of the current direction and independent of the current direction. It's been found. This phenomenon is due to the giant magnetoresistive effect (GM
R), and it is explained that it appears due to the difference in electrical resistance between the case where the magnetizations of the two ferromagnetic layers via the non-magnetic layer are antiparallel and the case where they are parallel when a magnetic field is applied. There is.

As a mechanism for producing an antiparallel state of magnetization, a method utilizing antiferromagnetic exchange coupling between ferromagnetic layers [Phys. Rev. Lett. , Vol. 66 (19
91), p. 2152 to 2155] using different coercive forces of two types of ferromagnetic layers [J. Phys. So
c. Jap. , Vol. 59 (1990), p. 306
1-3064], one in which two ferromagnetic layers sandwiching a non-magnetic layer are applied with an exchange bias to fix the magnetization [J.
Appl. Phys. , Vol. 69 (1991),
p. 4774-4779] utilizing magnetostatic coupling between two ferromagnetic layers [Science, Vol. 261
(1993), p. 1021-1024] and the like have been reported.

The one utilizing the antiferromagnetic exchange coupling between the ferromagnetic layers has a large ΔR / R, but has a strong magnetization coupling.
A very large magnetic field is required to utilize the magnetoresistive effect.

A structure utilizing different coercive forces of two types of ferromagnetic layers has a structure in which a nonmagnetic layer having a large film thickness is sandwiched between two types of ferromagnetic layers to break the coupling between the magnetization layers. . For this reason, a resistance change occurs with a small magnetic field, but ΔR / R does not become larger than that of the antiferromagnetic exchange coupling film even when the number of layers is increased.

An antiferromagnetic material biased to one of the ferromagnetic layers is called a spin pulp film and is characterized in that its magnetization curve is shifted in the magnetic field direction. By combining the ferromagnetic layers, high magnetic field sensitivity and low hysteresis can be obtained, but since the distance between the ferromagnetic layers that breaks the coupling between layers is large, the ΔR / R is small and the antiferromagnetic material has a high electric resistance. Since a film is used, even if multiple layers are used, ΔR /
R does not become too large.

The magnetostatic coupling between the two ferromagnetic layers has a very high magnetic field sensitivity but a small ΔR / R.

[0010]

The main object of the present invention is to show a large ΔR / R with a small applied magnetic field, a high magnetic field sensitivity in the vicinity of the zero magnetic field, and a magnetoresistive effect curve within the operating magnetic field range. It is to provide a laminated film for a magnetoresistive effect element having a small hysteresis.

[0011]

According to the present invention, a thin film composed of a non-magnetic metal film and a ferromagnetic metal film is formed on a substrate by (non-magnetic metal film / ferromagnetic metal film) / (non-magnetic metal film /
(Ferromagnetic metal film) i / (non-magnetic metal film) (non-magnetic metal film / ferromagnetic metal film) / (non-magnetic metal film /
(Ferromagnetic metal film) i / non-magnetic metal film, [where i is a repetition of 1 or 2 or more] repeated two or more times.
For each of the two, the interface magnetic anisotropy of the two-layer film composed of two (non-magnetic metal film / ferromagnetic metal film) is larger on the substrate side, and the difference between the two interface magnetic anisotropies is larger. 0.1
The magnetoresistive effect laminated film is characterized by having an erg / cm ² or more.

Furthermore, in the method of manufacturing a magnetoresistive effect laminated film, a magnetic field is applied in one direction within the film surface when each of the above-mentioned thin film layers is formed.

[0013]

Considering a laminated film in which several ferromagnetic metal layers laminated via non-ferromagnetic metal layers have two different magnitudes of magnetic anisotropy, the magnetization of each ferromagnetic metal layer is In the case of reversing with different magnetic fields depending on the magnitude of the magnetic anisotropy of, the magnetization curve of this laminated film has two different coercive forces. Since the reversal fields of the magnetization are deviated into two, depending on the magnitude of the magnetic field, a parallel or anti-parallel state appears in the magnetization direction between the ferromagnetic metal layers, and the magnitude of the electric resistance changes. As the magnetic anisotropy of a thin film, in addition to the crystalline magnetic anisotropy peculiar to the substance, the shape magnetic anisotropy depending on the film thickness, there is a magnetic anisotropy that changes when laminated on another substance, The magnitude of magnetic anisotropy can be changed by utilizing these things.

Generally, (non-magnetic metal film / ferromagnetic metal film)
In order to obtain the magnetic anisotropy of the two-layer film composed of, from the magnetization curve, the magnetization M ⊥ and M ‖ when an external magnetic field is applied perpendicularly to the film and in the film plane are obtained. Difference of (M
It can be obtained by integrating (⊥-M‖) in the entire magnetic field range (0 to H _sat ) and dividing by the volume V of the entire ferromagnetic layer. That is, if the effective magnetic anisotropy constant is K _eff ,

[0015]

[Equation 1]

It is expressed as On the other hand, the thickness of the ferromagnetic layer is t _F
Then, K _eff × t _F is approximately linearly related to t _F , and if K _s and K _v are constants, then K _eff × t _F = K _s + K _v × t _F , The intercept K _s is called interface magnetic anisotropy, and the slope K _v is called volume magnetic anisotropy.

The interface magnetic anisotropy indicates the anisotropy at the interface of (non-magnetic metal film / ferromagnetic metal film), and the degree of dependence of the non-magnetic metal film and the ferromagnetic metal film on the substance is large. Moreover, it is also possible to look it up in a document or the like without the need for the experiment as described above.

Since the magnetoresistive layered film of the present invention has a structure in which two ferromagnetic metal layers are laminated on different nonmagnetic metal layers, the magnetic anisotropy of the two ferromagnetic metal layers is It is different for the above reasons.

Further, in the case of the present invention, since the thickness of the ferromagnetic metal film is relatively small, (non-magnetic metal film / ferromagnetic metal film)
The magnitude of the magnetic anisotropy of the two-layer film composed of can be estimated by comparing the interface magnetic anisotropy. Therefore, as a result of intensive studies, the present invention has an interface magnetic anisotropy of 0.1 erg / on a two-layer film composed of (nonmagnetic metal film / ferromagnetic metal film).
Another (non-magnetic metal film / ferromagnetic metal film) smaller than cm ²
It has been found that by laminating the two-layer film composed of the above, a large difference occurs in the magnetic anisotropy of the two ferromagnetic metal layers, and as a result, a large ΔR / R is obtained.
Further, in the magnetoresistive layered film of the present invention, even if the distance between the two ferromagnetic metal layers is small, the respective magnetizations are inverted by different magnetic fields, so that a large resistance change occurs with a small applied magnetic field.

Further, since each layer can be selected from materials having low electric resistance, it is possible to further increase ΔR / R by forming multiple layers.

In the magnetoresistive film utilizing the different coercive forces of the above two types of ferromagnetic layers, each ferromagnetic layer is laminated on one type of non-magnetic layer, so that two types of ferromagnetic layers are used. The difference in magnetic anisotropy is caused only by the difference in crystal magnetic anisotropy of the ferromagnetic layers. That is, in order to have two different magnetic anisotropies, it is essential that there are two types of ferromagnetic layers. However, according to the present invention, different magnetic anisotropy is obtained by utilizing the magnetic anisotropy which is changed by stacking the ferromagnetic layer on another substance.

[0022]

Specific Structure The specific structure of the present invention will be described in detail below. FIG. 1 is a sectional view schematically showing the structure of the invention of claim 1. In the figure, 11 is a substrate, 1 is a non-magnetic metal film, 2 is a ferromagnetic metal film, 3 is a non-magnetic metal film, 4 is a ferromagnetic metal film,
a is a repeating unit that indicates a two-layer film in which 4 is laminated on 3 and the number of repetitions of a is i. 5 is a non-magnetic metal film, 21
Is a Cu lead for passing an electric current. 2 is a sectional view schematically showing the structure of the invention of claim 2,
The meanings of 1, 2, 3, 4, a, and i are the same as those in FIG. 1 above, and b is such that 2 is laminated on 1 and a is laminated i times on it, and a nonmagnetic metal is further added. A repeating unit that refers to a laminated film in which films 5 ′ are laminated, and the number of repetitions of b is n (2
The above integer).

As the non-magnetic metal film 1, a ferromagnetic metal film 2 is used.
As a non-magnetic substance that has a small solid solubility with and can have a larger interfacial magnetic anisotropy when laminated with a ferromagnetic metal film,
Cr, Cr alloy, V, V alloy, Pd, Pd alloy, Pt,
Pt alloy etc. are illustrated. The thickness of this thin film is 5 to 200
It is preferably in the range of Å. When the film thickness exceeds 200Å, the electrical resistance is determined by this layer, and as a result,
ΔR / R decreases. On the other hand, if it is thinner than 5Å, it becomes difficult to form a film.

The constituent materials of the ferromagnetic metal films 2 and 4 are Co, Fe, Ni, Co-Fe, Co-Ni and Ni.
-Fe, Ni-Fe-Co, etc. are illustrated. Especially △ R /
Co and Co-Fe are suitable for increasing R, and Ni-Fe and Co-Ni are suitable for increasing magnetic field sensitivity and decreasing hysteresis. The thickness of such ferromagnetic metal films 2 and 4 is not particularly limited as long as it is in the range of 5 to 200Å. ΔR / R decreases when the thickness is less than 5Å or thicker than 200Å. The ferromagnetic metal films 2 and 4 may be different. However, in that case, the ferromagnetic metal film 4 needs to be softer than 2. When 2 is softer than 4, ΔR / R, magnetic field sensitivity becomes small, and hysteresis becomes large.

As the constituent material of the non-magnetic metal film 3, the solid solubility with the ferromagnetic metal films 2 and 4 is small, and the interface magnetic anisotropy when the ferromagnetic metal films 4 are laminated is (non-magnetic metal film). 0.1er from the interface magnetic anisotropy of film 1 / ferromagnetic metal film 2)
Cu, A as a non-magnetic substance having a smaller g / cm ² or more
g and the like are preferable. The thickness of the non-magnetic metal film 3 is 5 to 50Å
If the range is less than 5Å and exceeds 50Å, △ R
/ R becomes smaller.

The constituent material of the nonmagnetic metal film 5 is required to have a small solid solubility with the ferromagnetic metal film 4, but is not particularly limited. The thickness of the nonmagnetic metal film 5 is 5 to 200.
The range of Å is preferable. Above a film thickness of 200Å, the electrical resistance is determined by this layer, resulting in a small ΔR / R. On the other hand, if it is thinner than 5Å, it becomes difficult to form a film.

As a constituent material of the nonmagnetic metal film 5 ', a material having a small solid solubility with the ferromagnetic metal film 4 and different from the nonmagnetic metal film 1 is preferable. The thickness of the non-magnetic metal film 5'is 5 to 2
A range of 00Å is preferred. When the film thickness exceeds 200Å,
The electrical resistance is determined by this layer, so that ΔR /
R becomes small. On the other hand, if it is thinner than 5Å, it becomes difficult to form a film.

There are no particular restrictions on the number of repetitions i in the first and second aspects of the present invention. As the number of repetitions increases, ΔR / R increases, but the influence of the coupling between the ferromagnetic layers becomes stronger. On the other hand, if the number of repetitions is too large, the electric resistance of the entire laminated film becomes small, which causes a problem in practical use.

In the invention of claim 2 of the present invention, the number of repetitions is an integer of 2 or more, and there is no particular upper or lower limit, and it may be appropriately selected according to the purpose. As the number of iterations increases, △
R / R increases, but if the number of repetitions becomes too large,
The electric resistance of the entire laminated film becomes small, which causes a problem in practical use.

The magnetoresistive effect curve of the embodiment of the present invention is shown in FIG.
Shown in The magnetization curve of the magnetoresistive layered film is shown in FIG. In the magnetoresistive effect curve, when the magnetic field is changed from negative to 0 and further to positive, ΔR / R sharply rises at a low magnetic field. The maximum slope here is the magnetic field sensitivity (% / Oe)
Is defined. After the ΔR / R reaches its maximum, it decreases gently and then drops sharply from a certain magnetic field. The magnetization curve has two coercive forces H _C1 and H _C2 as shown in FIG.

FIG. 5 shows a magnetoresistive effect curve when the magnetic field is applied and returned until just before ΔR / R reaches its maximum. The maximum opening width w of the magnetoresistive effect curve at this time is defined as the hysteresis width. When the magnetoresistive layered film of the present invention is used as a magnetic head or a magnetic sensor, the smaller the hysteresis width is, the smaller the fluctuation of the output voltage can be suppressed.

The substrate material in the present invention is glass, Si, sapphire, MgO, GaAs, GaIn.
P, GaAlAs, or the like can be used. Further, a base layer may be added to the substrate so that the laminated film has a flat interface. Further, a protective film for preventing oxidation may be formed on the outermost surface of the laminated film.

In forming the magnetoresistive layered film of the present invention, by applying a magnetic field of 500 Oe or less in one direction within the film surface, ΔR / R and magnetic field sensitivity are improved, and within the operating magnetic field range. The hysteresis in the magnetoresistive effect curve becomes small. When a magnetic field exceeding 500 Oe is applied, ΔR / R
Becomes smaller.

[0034]

EXAMPLES Examples of the present invention will be specifically described below.

Example 1 A glass substrate was evacuated to 1 × 10 to ⁷ Torr in a vacuum chamber, and then Ar gas was added to the gas for 5 times.
Introduced up to × 10 to ³ Torr. By magnetron sputtering using Pt, Co and Cu as targets, the Pt film 30Å as the non-magnetic metal film 1, the Co film 90Å as the ferromagnetic metal film 2, and the Cu film 11Å as the non-magnetic metal film 3.
As the ferromagnetic metal film 4, a Co film 90Å and a non-magnetic metal film 5 a Cu film 11Å were sequentially laminated to form a five-layer film. Further, Cu leads were formed on this five-layer film. A sample with a shape of 3 mm × 10 mm was prepared from this five-layer film, and the electric resistance when an external magnetic field was applied up to ± 500 Oe so as to be perpendicular to the current in the film plane was measured by the 4-terminal method at room temperature. . ΔR / R in the magnetoresistive effect curve was obtained by ΔR / R (%) = 100 × (R−R _min ) / R _min with the minimum electric resistance as R _min . Moreover, the magnetic characteristics were measured by a vibration type magnetometer. The interface magnetic anisotropy was obtained by an experiment in which the thickness of the ferromagnetic metal in the two-layer film composed of (nonmagnetic metal film / ferromagnetic metal film) was changed. The magnetoresistance effect curve is shown in FIG. 3 and the magnetization curve is shown in FIG.

The interface magnetic anisotropy is 1.3e for Pt / Co.
rg / cm ² , Cu / Co is 0.18 erg / cm ² , ΔR / R is 21.5%, and the magnetic field sensitivity is small despite the nonmagnetic metal film 3 (Cu) having a thin film thickness of 11Å. Is 0.5
A characteristic of 5% / Oe was obtained.

Comparative Example 1 In the same manner as in Example 1, the nonmagnetic metal film 1 was replaced with the Cu film 30.
Å, the ferromagnetic metal films 2 and 4 are Co films 90 Å, and the nonmagnetic metal films 3 and 5 are Pt films 11 Å
A Cu lead was formed on this 5-layer film, and the magnetoresistive effect was measured in the same manner as in Example 1. The interface magnetic anisotropy is the same as in Example 1, but ΔR / R is 3.5% and the magnetic field sensitivity is 0.0.
It was 6% / Oe.

Example 2 Similar to Example 1, the Pt film 30 was used as the non-magnetic metal film 1.
Å, 5 wt% Fe-95 as the ferromagnetic metal films 2 and 4
wt% Co alloy film 90Å, non-magnetic metal films 3 and 5 are C
A five-layer film having a u film of 12 Å was prepared, and Cu was formed on the five-layer film.
Leads were formed and the magnetoresistive effect was measured in the same manner as in Example 1. △ R / R is 23.2%, magnetic field sensitivity is 0.50
A characteristic of% / Oe was obtained. The interfacial magnetic anisotropy is P
t / Fe-Co is 1.4 erg / cm ² , Cu / Fe-
Co is 0.21 erg / cm ² .

Comparative Example 2 In the same manner as in Example 1, the nonmagnetic metal film 1 was replaced with the Cu film 30.
Å, the ferromagnetic metal films 2 and 4 are Co films 90 Å, and the non-magnetic metal films 3 and 5 are Ag films 11 Å to form a five-layer film,
A Cu lead was formed on this 5-layer film, and the magnetoresistive effect was measured in the same manner as in Example 1. ΔR / R was 5.2%, and magnetic field sensitivity was 0.02% / Oe. The interfacial magnetic anisotropy is such that Cu / Co is 0.18 erg / cm ² , Ag / Co
Is 0.13 erg / cm ² .

Example 3 In the same manner as in Example 1, the V film 50 was used as the non-magnetic metal film 1.
Å, the ferromagnetic metal films 2 and 4 are Co films 70 Å, and the non-magnetic metal films 3 and 5 are Cu films 11 Å
A Cu lead was formed on this 5-layer film, and the magnetoresistive effect was measured in the same manner as in Example 1. ΔR / R is 19.1%,
A magnetic field sensitivity of 0.57% / Oe was obtained. The interface magnetic anisotropy is V / Co of 1.1 erg / cm ² , C
u / Co is 0.18 erg / cm ² .

Example 4 In the same manner as in Example 1, the Cr film 30 was used as the non-magnetic metal film 1.
Å, the ferromagnetic metal films 2 and 4 are Co films 95 Å, and the non-magnetic metal films 3 and 5 are Cu films 11 Å
A Cu lead was formed on this 5-layer film, and the magnetoresistive effect was measured in the same manner as in Example 1. ΔR / R is 11.7%,
A magnetic field sensitivity of 0.59% / Oe was obtained. The interfacial magnetic anisotropy is 0.71 erg / c for Cr / Co
m ² and Cu / Co are 0.18 erg / cm ² .

Example 5 In the same manner as in Example 1, 13 wt% Mn was added to the nonmagnetic metal film 1.
-87 wt% Cr alloy film 50Å, ferromagnetic metal films 2 and 4 Co film 60Å, non-magnetic metal films 3 and 5 Cu film 1
As 3Å, a non-magnetic metal film 1, a ferromagnetic metal film 2, a multilayer film in which a non-magnetic metal film 3 and a ferromagnetic metal film 4 are alternately laminated 15 times, and a non-magnetic metal film 5 are laminated in this order. A film (i = 15, n = 1) was prepared, a Cu lead was formed thereon, and the magnetoresistive effect was measured in the same manner as in Example 1. △ R / R is 26.7%, magnetic field sensitivity is 0.11% / O
The characteristic e was obtained. Interfacial magnetic anisotropy is 13 wt
% Mn-87 wt% Cr / Co is 0.70 erg / cm
² , Cu / Co is 0.18 erg / cm ² .

Example 6 Pd film 40Å, Co film 77Å, Cu film 1 on a glass substrate
1Å, Co film 77Å, Cu film 11Å, Co film 77Å, P
The d-film 40Å was sequentially laminated (i = 2, n = 1), Cu leads were formed thereon, and the magnetoresistive effect was measured in the same manner as in Example 1. ΔR / R is 21.7%, magnetic field sensitivity is 0.
A characteristic of 44% / Oe was obtained. Interfacial magnetic anisotropy, Pd / Co is 1.2erg / cm ^2, Cu / Co is 0.18erg / cm ^2.

Example 7 The five-layer film Pt30Å / Co90 of Example 1 was formed on a glass substrate.
A laminated film (i = 1, n = 3) having a structure in which Å / Cu11Å / Co90Å / Cu11Å is repeatedly laminated three times is formed, Cu leads are formed on the laminated film, and magnetic resistance is obtained in the same manner as in Example 1. The effect was measured. The characteristics of ΔR / R of 30.3% and magnetic field sensitivity of 0.40% / Oe were obtained.

Example 8 In the same manner as in Example 1, the nonmagnetic metal film 1 was Pt30Å, the ferromagnetic metal film 2 was Co film 90Å, and the nonmagnetic metal films 3 and 5 were used.
Cu film 12Å and ferromagnetic metal film 4 21 wt% Fe-7
A 5-layer film having a 9 wt% Ni alloy film 90Å was prepared, Cu leads were formed on the 5-layer film, and the magnetoresistive effect when an external magnetic field was applied up to ± 50 Oe was measured in the same manner as in Example 1. . ΔR / R is 18.3%, magnetic field sensitivity is 0.8
A characteristic of 9% / Oe was obtained. The hysteresis width was 10 Oe. Interfacial magnetic anisotropy is Pt / Co
Is 1.3 erg / cm ² , Cu / Fe-Ni is -0.2
It is 3 erg / cm ² .

Example 9 A Pt film 30Å as the non-magnetic metal film 1, a Co film 77Å as the ferromagnetic metal films 2 and 4, a Cu film 11Å as the non-magnetic metal films 3 and 5, and a magnetic field of 240 Oe on the glass substrate. A 5-layer film was produced by laminating while applying in-plane. Further, Cu leads were formed on the five-layer film, and the magnetoresistive effect was measured in the same manner as in Example 1. ΔR / R is 24.
The characteristics were 5% and the magnetic field sensitivity was 0.63% / Oe.

Example 10 A Pt film 30Å as a non-magnetic metal film 1, a Co film 70Å as a ferromagnetic metal film 2, a Cu film 11Å as a non-magnetic metal film 3 and a 21 wt% Ni as a ferromagnetic metal film 4 on a glass substrate.
A -79 wt% Fe mixed metal film 70Å and a Cu film 11Å as the non-magnetic metal film 5 were laminated while applying a magnetic field of 240 Oe in the film plane to form a five-layer film. Further, a Cu lead was formed on this five-layer film, and the magnetoresistive effect was measured when an external magnetic field was applied up to ± 50 Oe in the same manner as in Example 1. △ R / R is 19.7%, magnetic field sensitivity is 1.1% / Oe
The characteristic was obtained. Also, the hysteresis width is 5 Oe
Met.

[0048]

INDUSTRIAL APPLICABILITY The present invention has a large magnetoresistance change rate in a small magnetic field, has a high magnetic field sensitivity in the vicinity of a zero magnetic field, and has a small hysteresis width of the magnetoresistance effect curve in the operating magnetic field range. Provide a membrane. As a result, not only the sensitivity of the conventional magnetic sensor and magnetic head can be increased, but also the processing speed of the magnetoresistive effect memory can be expected to be increased.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing a structure of a magnetoresistive effect laminated film according to a first aspect of the present invention.

FIG. 2 is a cross-sectional view schematically showing a structure of a magnetoresistive effect laminated film according to a second aspect of the present invention.

3 is a magnetoresistive effect curve of a magnetoresistive effect laminated film in Example 1. FIG.

FIG. 4 is a magnetization curve of a magnetoresistive layered film in Example 1.

FIG. 5 is a diagram illustrating a hysteresis width in a magnetoresistive effect curve.

[Explanation of symbols]

 1 non-magnetic metal film 2 ferromagnetic metal film 3 non-magnetic metal film 4 ferromagnetic metal film 5 non-magnetic metal film 5'non-magnetic metal film 11 substrate 21 Cu lead for passing current.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 13, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

An antiferromagnetic material biased to one of the ferromagnetic layers is called a spin valve film and is characterized in that its magnetization curve is shifted in the magnetic field direction. By combining the ferromagnetic layers, high magnetic field sensitivity and low hysteresis can be obtained, but since the distance between the ferromagnetic layers that breaks the coupling between layers is large, the ΔR / R is small and the antiferromagnetic material has a high electric resistance. Since a film is used, even if multiple layers are used, ΔR /
R does not become too large.

Claims (3)

[Claims] 1. A thin film comprising a non-magnetic metal film and a ferromagnetic metal film on a substrate (non-magnetic metal film / ferromagnetic metal film) /
(Non-magnetic metal film / ferromagnetic metal film) i (where i is 1 or (2) shows a repetition number of 2 or more of (non-magnetic metal film / ferromagnetic metal film)) A magnetoresistive layered film, comprising the two (non-magnetic metal film /
Of the interface magnetic anisotropy of a two-layer film composed of a ferromagnetic metal film), the one on the substrate side is larger, and the difference between the two interface magnetic anisotropies is 0.1 erg / cm ² or more. Magneto-resistive effect laminated film. 2. A thin film composed of a nonmagnetic metal film and a ferromagnetic metal film is formed on a substrate (nonmagnetic metal film / ferromagnetic metal film) /
Repeated twice or more in the order of (non-magnetic metal film / ferromagnetic metal film) i / non-magnetic metal film (where i represents 1 or (non-magnetic metal film / ferromagnetic metal film) repeated number of 2 or more) A magnetoresistive laminated film characterized by being laminated, wherein one of the two (non-magnetic metal film / ferromagnetic metal film) interface magnetic anisotropy on the substrate side Is large, the difference between the two interface magnetic anisotropies is 0.1 erg / cm
A magnetoresistive layered film having a number of ² or more. 3. A method of manufacturing a magnetoresistive effect laminated film according to claim 1 or 2, wherein a magnetic field is applied in one direction within a film surface in the film formation of the magnetoresistive effect laminated film.