JPH0849063A - Magnetoresistive film - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a magnetoresistive effect film in which deterioration of magnetoresistive effect characteristics does not easily occur even at high temperatures and a giant magnetoresistive effect is stably obtained. A magnetoresistive effect film having an artificial lattice film structure in which conductor layers and magnetic layers are alternately laminated, or a spin valve structure in which magnetic layers, conductor layers and magnetic layers are laminated in this order In the magnetoresistive film, the main component of the conductor layer is C
As an element selected from u, Ag, and Cr, 0.1 to 30 atomic% of an additional element having a solid solution upper limit of 1% or less at room temperature is added to the conductor layer. Alternatively, if the main components of the magnetic layer are Fe, Co, and Ni,
0.1% to 30 atomic% of an additional element having a solid solution upper limit of 1% or less at room temperature for the element which is the main component is added to the magnetic layer.
To add.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive film applied to a magnetic field detecting element such as a magnetic sensor or a reproducing head for a magnetic disk device, and more particularly to improving heat resistance.

[0002]

2. Description of the Related Art A magnetoresistive film having a magnetoresistive effect is used as a magnetic field detecting element and is widely used in the fields of magnetic sensors, magnetic heads and the like.

Conventionally, the above-mentioned magnetoresistive film is mainly made of Fe.
-Ni alloy films (so-called permalloy films) have been used. However, the rate of change in magnetoresistance of the permalloy film is small,
Considering the correspondence to high density magnetic recording which is expected to further develop in the future, it cannot be said that the sensitivity is sufficient.

On the other hand, in recent years, attention has been paid to artificial lattice films in which different kinds of metals are alternately laminated by several atomic layers. inside that,
It has been reported that an artificial lattice film made of a laminated body of a magnetic layer made of Fe and a conductor layer made of Cr can obtain a magnetoresistance change rate of several tens of percent (hereinafter referred to as "giant magnetoresistance effect"). Therefore, application to a magnetoresistive film is expected. (Physical Review Letters, Volume 61,
After that, it has been reported that, besides the combination of the Fe layer and the Cr layer, a combination of the magnetic layer as the Co layer and the conductor layer as the Cu layer can also obtain the giant magnetoresistive effect. (Physical Review Letters, Vol. 66, p. 2152, 1991) Also, by using an alloy that combines three elements of iron, nickel and cobalt in the magnetic layer, a large change in resistance can be obtained even with a small change in magnetic field. It has been reported that the sensitivity to an external magnetic field is improved and that it is effective from a practical viewpoint.

A giant magnetoresistive effect can be obtained even with a film (so-called spin valve film) whose main constituent is a three-layer film in which a magnetic layer, a conductor layer and a magnetic layer are laminated in this order. It has been reported. (Journal of Magnetics and Magnetic Materials, 9
(Vol. 3, 101 pages, 1991)

[0006]

However, in the magnetoresistive film having the above-mentioned laminated film structure, diffusion occurs between the layers due to heat. Therefore, such a magnetoresistive effect film has a drawback that the magnetoresistive effect characteristics are likely to deteriorate at high temperatures.

The present invention has been proposed in view of such conventional circumstances, and the magnetoresistive effect is less likely to deteriorate even at high temperature, and the giant magnetoresistive effect can be stably obtained. The purpose is to provide a membrane.

[0008]

The reason why the giant magnetoresistive effect is observed in a magnetoresistive film having an artificial lattice film structure in which conductor layers and magnetic layers are alternately laminated is that conduction electrons in the conductor are observed. RKKY (Ludderman, Kittel, Kasuya, Yoshida) interaction between the magnetic layers via the magnetic field, and the opposing magnetic layers are antiferromagnetically coupled to each other, resulting in an antiparallel spin state, resulting in spin dependence. It is considered that scattering occurs, and thus a large magnetoresistive effect is obtained.

Also, in a magnetoresistive effect film having a spin valve structure having a three-layer film having a magnetic material layer, a conductor layer and a magnetic material layer laminated in this order as a main constituent, similarly, an antiparallel spin state is generated. It is considered that spin-dependent scattering occurs, which results in a large magnetoresistive effect.

As described above, it is considered that the large magnetoresistive effect is obtained in these structures when the antiparallel spin state can be achieved. However, the antiparallel spin state is greatly increased by heat. to be influenced. Therefore, as a result of further intensive studies by the present inventors, an antiparallel spin state was achieved by adding an element that is difficult to form a solid solution to the conductor layer or by adding an element that is difficult to form a solid solution to the magnetic layer. It has been found that the influence of the heat of is reduced, and the deterioration of the magnetoresistive effect characteristics at high temperature can be prevented.

The magnetoresistive effect film of the present invention made on the basis of the finding that an element which is hard to form a solid solution should be added to the conductor layer is an artificial layer formed by alternately laminating conductor layers and magnetic layers. A magnetoresistive film having a lattice film structure, wherein the conductor layer contains an element selected from Cu, Ag, and Cr as a main component,
In addition, the upper limit of the solid solution with respect to the element which is the main component is 0.1% to 30 atom% of the additional element at room temperature of 1% or less. Alternatively, in a magnetoresistive film having a spin valve structure in which a magnetic layer, a conductor layer, and a magnetic layer are laminated in this order, the conductor layer contains an element selected from Cu, Ag, and Cr as a main component, In addition, the upper limit of the solid solution with respect to the element which is the main component is 0.1% to 30 atom% of the additional element at room temperature of 1% or less.

In the magnetoresistive effect film, when the main component of the conductor layer is Cu, the additive elements added to the conductor layer are Ag, B, Bi, C, Co, Fe, Hg, I.
An element selected from r, Mo, Na, Nb, Pb, Pt, V and Zr is preferable. When the main component of the conductor layer is Ag, the additive element added to the conductor layer is B.
e, Bi, Co, Cr, Cu, Fe, Ge, Ir, N
An element selected from i, Pb, Si and U is preferable.

In the magnetoresistive film, the magnetic layer is made of Fe, Co, Ni, Cr, V, Mo, Nb, T.
a, W, Re, Ru, Cu, Rh, Pd, Ir, Pt,
B, C, N, O, Si, Al, Ga, Ge, Sn, Sb
Among these elements, a magnetic body composed of at least one kind of element, which is a ferromagnetic body at room temperature, is used. In particular,
1 to 50 atomic% Cu, and Fe, Co, Ni
It is preferable to use a magnetic material layer containing at least one selected from the above, and in this case, Fe, Co, and Ni contained in the magnetic material layer have a composition in order to improve sensitivity to an external magnetic field. It is particularly preferred to set the ratio as follows:

Fe _x Co _y Ni _z (x, y, z are atomic%)
Then, 5 ≦ x ≦ 40, 20 ≦ y ≦ 90, 5 ≦ z ≦ 70, x + y
+ Z = 100 On the other hand, the magnetoresistive effect film of the present invention made on the basis of the finding that an element which is difficult to form a solid solution should be added to the magnetic layer is formed by alternately laminating conductor layers and magnetic layers. A magnetoresistive film having an artificial lattice film structure, wherein the magnetic layer is F
It contains e, Co, and Ni as main components, and contains 0.1 to 30 atom% of an additional element whose solid solution upper limit with respect to these main component elements is 1% or less at room temperature. Alternatively,
A magnetoresistive film having a spin-valve structure in which a magnetic layer, a conductor layer, and a magnetic layer are laminated in this order, wherein the magnetic layer contains Fe, Co, and Ni as main components, and these main components The upper limit of solid solution for the element is 0.1% to 30 atomic% of the additional element at room temperature of 1% or less.

In the above magnetoresistive film, the additive element added to the magnetic layer is, for example, Ag,
B, Bi, C, Co, Cr, Fe, Hg, Ir, Li,
Examples include elements selected from Mo, Na, Nb, Pb, V, Pt, and Zr.

[0016]

In the magnetoresistive effect film having the artificial lattice film structure or the magnetoresistive effect film having the spin valve structure, the conductive layer contains 0.1 to 30 additional elements which are hard to form a solid solution with the element as the main component.
0.1 to 30% of the additive element which is hard to form a solid solution with the element which is the main component of the magnetic material layer by adding at 30% by atom.
By adding at%, it becomes difficult for the magnetoresistive effect characteristics to deteriorate at high temperature, and the giant magnetoresistive effect can be stably obtained.

[0017]

EXAMPLES Examples and comparative examples and their evaluation will be described in detail below with reference to the drawings.

Example 1 As shown in FIG. 1, on a ferrite substrate 1, a sputtering apparatus was used, and a magnetic layer 2 made of Fe ₂₀ Ni ₄₅ Co ₃₅ and having a thickness of 1.0 nm and Cu were the main components. And a thickness of 2.1 to which Ag, which is an element that is difficult to form a solid solution with Cu, is added.
The conductor layers 3 having a thickness of 30 nm were alternately laminated for 30 cycles to form a magnetoresistive effect film having an artificial lattice film structure.

The sputtering apparatus used in this example is shown in FIG. This sputtering apparatus includes two targets 5 and 6 in a vacuum container 4, two shutters 7 and 8 arranged to face each target 5 and 6 to control the film thickness by an opening / closing operation, and each target 5 , 6 and a turntable 9 that rotates on. And the substrate 1
0 is attached to the turntable 9 so as to face the targets 5 and 6 through the shutters 7 and 8, and the rotation A of the turntable 9 causes the 0 to pass through the targets 5 and 6 alternately. Has become.

In forming the magnetoresistive film having the artificial lattice film structure, the film forming conditions for each layer were as follows.

Sputtering gas: Argon Sputtering gas pressure: 0.3 Pa Applied power: 300 W Deposition rate: 0.1 to 0.5 nm / sec In the above magnetoresistive effect film, on the Cu target,
By carrying out sputtering after mounting an Ag chip having a diameter of 3 mm and a thickness of 2 mm, C which is the main component of the conductor layer
Ag was added to u. The amount of Ag added was controlled by the number of Ag chips placed on the Cu target.

Then, the influence of the addition amount of Ag on the heat resistance of the magnetoresistive film was measured. Measurement is A to the conductor layer
The magnetoresistive effect film formed as described above with the addition amounts of g being 0.1 atom%, 5 atom%, 30 atom% and 40 atom%, and the magnetic film formed without adding Ag as a comparative example. The magnetoresistive effect films were subjected to heat treatment at 230 ° C., 260 ° C., 290 ° C., and 320 ° C. for 1 hour in vacuum, and the magnetoresistive change rate was investigated. . The results are shown in Fig. 3.

From the results shown in FIG. 3, it is understood that the thermal deterioration of the magnetoresistive effect can be prevented by adding Ag to the conductor layer. Further, when 0.1 at% or more of Ag is added, the effect of preventing thermal deterioration is recognized, but when 40 at% of Ag is added, the magnetoresistive effect in the initial state before heat treatment is reduced. It turns out that it is not suitable. That is, it can be said that the appropriate addition amount of Ag is 0.1 to 30 atomic%.

Example 2 Similar to Example 1, except that the additive element to the conductor layer was changed from Ag to Pt, a magnetoresistive effect film was formed. Note that Pt
Is added on a Cu target with a diameter of 3 mm and a thickness of 2 m.
It was carried out by carrying out sputtering after mounting m Pt chips, and the amount of Cu added to the conductor layer was controlled by the number of Pt chips mounted on the Cu target.

Then, the influence of the amount of Pt added to the conductor layer on the heat resistance of the magnetoresistive film was measured. For the measurement, the amount of Pt added to the conductor layer was 0.1 at%, 5 at%, 30 at
Using a magnetoresistive effect film formed as described above at an atomic percentage of 40 atomic% and a magnetoresistive effect film formed without adding Pt as a comparative example, 230 ° C, 260 ° C, 290 ° C, and 3 in vacuum
After the heat treatment was performed at 20 ° C. for 1 hour, the rate of change in magnetoresistance was examined. FIG. 4 shows the results.

From the results shown in FIG. 4, it is understood that the thermal deterioration of the magnetoresistive effect can be prevented by adding Pt to the conductor layer. Further, when Pt is added to the conductor layer, Pt is less than 0.
If 1 atom% or more is added, the effect of preventing thermal deterioration is recognized, but if Pt is added at 40 atom%, the magnetoresistive effect in the initial state before heat treatment is reduced, which is not suitable. I understand. That is, Pt on the conductor layer
It can be said that 0.1 to 30 atomic% is suitable for the addition amount of.

In Example 1, the main component of the conductor layer is C.
In the magnetoresistive film having the artificial lattice film structure of u, Ag is added to the conductor layer, and in Example 2, the main component of the conductor layer is Cu.
In the magnetoresistive film of the artificial lattice film structure of
Although t is added, the elements to be added to the conductor layer are B, Bi, C, Co, Fe, Hg, I
Similarly, when r, Mo, Na, Nb, Pb, V, Zr, etc. were used, an improvement in the heat resistance of the magnetoresistive effect was recognized.

Example 3 As in Example 1, except that the main component of the conductor layer was Cu to A
Instead of g, the additive element to the conductor layer was changed from Ag to Cu to form a magnetoresistive film. The addition of Cu is Ag
This was performed by placing a Cu chip having a diameter of 3 mm and a thickness of 2 mm on the target and then performing sputtering.
The amount of Cu added to the conductor layer was set to 5 atom%.

Then, the magnetoresistive effect film and the magnetoresistive effect film formed without adding Cu as a comparative example were vacuum treated at 230 ° C., 260 ° C., 290 ° C., and 320 ° C. for 1 hour. After performing the heat treatment of 1., the rate of change in magnetoresistance was examined to examine the effect of addition of Cu on the heat resistance of the magnetoresistive film. Results are shown in FIG.

From the results shown in FIG. 5, it is understood that the thermal deterioration of the magnetoresistive effect can be prevented by adding Cu to the conductor layer.

In Example 3, the main component of the conductor layer was A.
Although Cu was added to the conductor layer in the magnetoresistive film having the artificial lattice film structure of g, the elements to be added to the conductor layer are Be, Bi, Co, Cr, Cu and F, which are hard to form a solid solution with Ag.
Also in the case of using e, Ge, Ir, Ni, Pb, Si, U, etc., the improvement of the heat resistance of the magnetoresistive effect was similarly recognized.

Example 4 As shown in FIG. 6, Example 1 was formed on a ferrite substrate 11.
Similarly to the above, using a sputtering device, a magnetic layer 12 made of permalloy and having a thickness of 200 nm, and a conductor layer 13 having a thickness of 5 nm and containing Cu as a main component and Ag, which is an element that is hard to form a solid solution with Cu, are added. And a magnetic layer 14 of permalloy having a thickness of 200 nm and an antiferromagnetic layer 15 of Fe ₅₀ Mn _{50 having} a thickness of 500 nm are laminated in this order to form a magnetoresistive film having a spin valve structure. did.

In forming the magnetoresistive film having the above spin valve structure, the film forming conditions for each layer were as follows.

Sputtering gas: Argon Sputtering gas pressure: 0.5 Pa Applied power: 300 W Deposition rate: 0.1-0.5 nm / sec Note that the addition of Ag was carried out in the same manner as in Example 1 except that the diameter was changed on the Cu target. Sputtering was performed after mounting an Ag chip having a thickness of 3 mm and a thickness of 2 mm. The amount of Ag added to the conductor layer was 5 atom%.

Then, the magnetoresistive effect film and a magnetoresistive effect film having a spin valve structure formed without adding Ag as a comparative example are 230 ° C., 260 ° C. and 290 ° C. in vacuum.
After the heat treatment was performed for 1 hour at 0.degree. C. and 320.degree. C., the magnetoresistance change rate was examined to examine the effect of the addition of Cu on the heat resistance of the magnetoresistive film. FIG. 7 shows the results.

From the results shown in FIG. 7, it is understood that the thermal deterioration of the magnetoresistive effect can be prevented by adding Ag to the conductor layer.

Example 5 In the same manner as in Example 4, except that the additive element to the conductor layer was changed from Ag to Pt, a magnetoresistive effect film was formed. Note that Pt
Is added on a Cu target with a diameter of 3 mm and a thickness of 2 m.
m Pt chips are sputtered on the conductor layer, and the amount of Cu added to the conductor layer is controlled by the number of Pt chips placed on the Cu target. It was made to be atomic%.

In the magnetoresistive film, the fourth embodiment is also used.
Similar to the above, improvement in heat resistance of the magnetoresistive effect was observed. Therefore, also in the magnetoresistive film having the spin valve structure, the thermal deterioration of the magnetoresistive effect can be prevented by adding Pt to the conductor layer.

In Example 4, the main component of the conductor layer was C.
In the magnetoresistive film of the spin valve structure of u, Ag is added to the conductor layer, and in Example 5, the main component of the conductor layer is C.
Although Pt was added to the conductor layer in the magnetoresistive film having the spin valve structure of u, the elements to be added to the conductor layer are B, Bi, C, Co, Fe, Hg, which are hard to form a solid solution with Cu,
Even when Ir, Mo, Na, Nb, Pb, V, Zr or the like was used, the improvement of the heat resistance of the magnetoresistive effect was similarly recognized.

Example 6 In this example, depending on the type of element added to the conductor layer,
In order to investigate whether the heat resistance of the magnetoresistive film changes,
The elements added to the conductor layer are Ag, B, Bi, C, Co,
Fe, Hg, Ir, Mo, Na, Nb, Pb, Pt,
As V and Zr, a magnetoresistive effect film was formed in the same manner as in Example 1 except that the additive element was changed for each. As a comparative example, the elements added to the conductor layer are Mn and N.
The magnetoresistive film was similarly formed for the materials i and Si. In each magnetoresistive effect film, the amount of the additional element added was 5 atom%.

Regarding each of the magnetoresistive films,
Magnetoresistance effect rate before heat treatment and 1 at 310 ° C in vacuum
After measuring the magnetoresistive effect rate after heat treatment for a time,
The effect of the type of element added to the conductor layer on the heat resistance of the magnetoresistive film was evaluated in the following three stages.

Good: The ratio of the magnetoresistive effect ratio before the heat treatment to the magnetoresistive effect ratio after the heat treatment is 50% or more.

Δ: The ratio of the magnetoresistive effect ratio before the heat treatment and the magnetoresistive effect ratio after the heat treatment is 30% or more and less than 50%.

X: The ratio of the magnetoresistive effect ratio before the heat treatment and the magnetoresistive effect ratio after the heat treatment is less than 30%.

When the additive element is not added to the conductor layer, the ratio of the magnetoresistive effect rate before the heat treatment and the magnetoresistive effect rate after the heat treatment is about 20%.

The results of the above evaluations are shown in Table 1.

[0047]

[Table 1]

From the results shown in Table 1, Ag, B, Bi, C, Co, Fe and H, which are elements that are difficult to form a solid solution in the conductor layer,
It can be seen that when g, Ir, Mo, Na, Nb, Pb, Pt, V, and Zr are added, thermal deterioration of the magnetoresistive effect is prevented. In addition, M, which is an element that easily forms a solid solution in the conductor layer
It can be seen that the addition of n, Ni and Si has no effect in preventing the thermal deterioration of the magnetoresistive effect.

Example 7 In this example, a sputtering apparatus was used in the same manner as in Example 1 on a ferrite substrate, and Fe ₂₀ Ni ₄₅ Co ₃₅ was the main component, which was an element that was hard to form a solid solution in FeNiCo.
A magnetic layer having a thickness of 1.0 nm and a conductor layer having a thickness of 2.1 nm made of Cu were alternately laminated for 30 cycles to form a magnetoresistive film having an artificial lattice film structure.

In forming the magnetoresistive film having the artificial lattice film structure, the film forming conditions for each layer were as follows.

Sputtering gas: Argon Sputtering gas pressure: 0.3 Pa Applied power: 300 W Deposition rate: 0.1-0.5 nm / sec In the above magnetoresistive effect film, a diameter of 3 mm and a thickness of 2 mm were formed on a FeNiCo target. Then, Ag was added to Fe ₂₀ Ni ₄₅ Co ₃₅ , which is the main component of the magnetic layer, by carrying out sputtering after mounting the Ag chip. The amount of Ag added was controlled by the number of Ag chips placed on the FeNiCo target.

Then, the influence of the added amount of Ag on the heat resistance of the magnetoresistive film was measured. For the measurement, the amount of Ag added to the magnetic layer was 0.1 at%, 5 at%, 30 at%,
And a magnetoresistive effect film formed as described above at 40 atomic% and a magnetoresistive effect film formed without adding Ag as a comparative example. After performing heat treatment at 230 ° C., 260 ° C., 290 ° C., and 320 ° C. for 1 hour, the rate of change in magnetoresistance was examined. The results are shown in Fig. 8.

From the results shown in FIG. 8, it is understood that the thermal deterioration of the magnetoresistive effect can be prevented by adding Ag to the magnetic layer. Further, when 0.1 at% or more of Ag is added, the effect of preventing thermal deterioration is recognized, but when 40 at% of Ag is added, the magnetoresistive effect in the initial state before heat treatment is reduced. It turns out that it is not suitable. That is, it can be said that the appropriate addition amount of Ag is 0.1 to 30 atomic%.

In Example 3, Ag was added to the magnetic material layer in the magnetoresistive film having the artificial lattice film structure in which the main component of the magnetic material layer was FeNiCo. However, the additive element to the magnetic material layer was fixed to FeNiCo. Insoluble elements B, Bi,
C, Co, Cr, Fe, Hg, Ir, Li, Mo, N
Similarly, when a, Nb, Pb, V, Pt, Zr, etc. were used, the improvement in heat resistance of the magnetoresistive effect was recognized.

Example 8 In this example, in order to investigate whether the heat resistance of the magnetoresistive film changes depending on the type of element added to the magnetic layer, the elements added to the magnetic layer are Ag, B, Bi, C, C
o, Cr, Fe, Hg, Ir, Li, Mo, Na, N
As b, Pb, V, Pt, and Zr,
A magnetoresistive effect film was formed in the same manner as in Example 7 except that the additive element was changed. Further, as a comparative example, a magnetoresistive effect film was similarly formed for Al and Ti as elements added to the magnetic layer. In each magnetoresistive effect film, the amount of the additional element added was 5 atom%.

Regarding each of the magnetoresistive films,
Magnetoresistance effect rate before heat treatment and 1 at 290 ° C in vacuum
After measuring the magnetoresistive effect rate after heat treatment for a time,
The effect of the type of element added to the magnetic layer on the heat resistance of the magnetoresistive effect film was evaluated in the following three stages.

◯: The ratio of the magnetoresistive effect rate before the heat treatment to the magnetoresistive effect rate after the heat treatment is 50% or more.

Δ: The ratio of the magnetoresistive effect ratio before the heat treatment to the magnetoresistive effect ratio after the heat treatment is 30% or more and less than 50%.

X: A ratio of the magnetoresistive effect ratio before the heat treatment and the magnetoresistive effect ratio after the heat treatment is less than 30%.

When no additional element is added to the magnetic layer, the ratio of the magnetoresistive effect rate before the heat treatment to the magnetoresistive effect rate after the heat treatment is about 20%.

The results of the above evaluations are shown in Table 2.

[0062]

[Table 2]

From the results shown in Table 2, Ag, B, Bi, C, Co, Cr and F, which are elements that are difficult to form a solid solution in the magnetic layer,
e, Hg, Ir, Li, Mo, Na, Nb, Pb, V,
It can be seen that the thermal deterioration of the magnetoresistive effect is prevented when Pt and Zr are added. It is also found that the addition of Al and Ti, which are elements that are likely to form a solid solution in the magnetic layer, is not effective in preventing thermal deterioration of the magnetoresistive effect.

[0064]

As is clear from the above description, in the magnetoresistive effect film of the present invention, deterioration of the magnetoresistive effect characteristics at high temperature is less likely to occur, and the giant magnetoresistive effect is stably obtained. Become.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part showing an example of a magnetoresistive effect film having an artificial lattice film structure to which the present invention is applied.

FIG. 2 is a schematic perspective view showing a configuration example of a sputtering apparatus used for producing a magnetoresistive effect film to which the present invention is applied.

FIG. 3 is a graph showing the change in magnetoresistance change rate when a magnetoresistive effect film having an artificial lattice film structure in which the main component of the conductor layer is Cu is heat-treated by changing the amount of Ag added to the conductor layer. It is a characteristic view which shows a result.

FIG. 4 is a graph showing the change in magnetoresistance change rate when a magnetoresistive effect film having an artificial lattice film structure in which the main component of the conductor layer is Cu is heat-treated by changing the amount of Pt added to the conductor layer. It is a characteristic view which shows a result.

FIG. 5: Changes in magnetoresistance change rate when a magnetoresistive effect film having an artificial lattice film structure in which the main component of the conductor layer is Ag is subjected to heat treatment were measured by changing the amount of Cu added to the conductor layer. It is a characteristic view which shows a result.

FIG. 6 is an enlarged sectional view of an essential part showing an example of a magnetoresistive effect film having a spin valve structure to which the present invention is applied.

FIG. 7 is a result of measuring the change in magnetoresistance change rate when a magnetoresistive film having a spin valve structure in which the main component of the conductor layer is Cu is heat-treated while changing the amount of Ag added to the conductor layer. FIG.

FIG. 8 shows changes in magnetoresistance change rate when a magnetoresistive effect film having an artificial lattice film structure in which the main component of the magnetic layer is FeNiCo is subjected to heat treatment by changing the amount of Ag added to the magnetic layer. It is a characteristic view which shows the measured result.

[Explanation of symbols]

 1 Substrate 2 Conductor Layer 3 Magnetic Layer 4 Vacuum Container 5,6 Target 7,8 Shutter 9 Turntable 10 Substrate 11 Substrate 12 Magnetic Material Layer 13 Conductor Layer 14 Magnetic Material Layer 15 Antiferromagnetic Material Layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01F 10/14 H01L 43/02 Z

Claims (7)

[Claims] 1. A magnetoresistive effect film having an artificial lattice film structure in which conductor layers and magnetic layers are alternately laminated, wherein the conductor layer contains an element selected from Cu, Ag, and Cr as a main component, and A magnetoresistive effect film characterized by containing 0.1 to 30 atom% of an additional element whose solid solution upper limit with respect to these main constituent elements is 1% or less at room temperature. 2. A magnetoresistive effect film having a spin valve structure comprising a magnetic layer, a conductor layer, and a magnetic layer laminated in this order, wherein the conductor layer contains an element selected from Cu, Ag, and Cr as a main component. And a magnetoresistive effect film containing 0.1 to 30 atomic% of an additional element whose solid solution upper limit with respect to these main constituent elements is 1% or less at room temperature. 3. The main component of the conductor layer is Cu, and the additive elements contained in the conductor layer are Ag, B, Bi, C, Co, Fe,
Hg, Ir, Mo, Na, Nb, Pb, Pt, V, Zr
The magnetoresistive film according to claim 1 or 2, wherein the magnetoresistive film is an element selected from the following. 4. The main component of the conductor layer is Ag, and the additive element contained in the conductor layer is Be, Bi, Co, Cr, Cu, F.
The magnetoresistive film according to claim 1 or 2, wherein the magnetoresistive film is an element selected from e, Ge, Ir, Ni, Pb, Si, and U. 5. In a magnetoresistive effect film having an artificial lattice film structure in which conductor layers and magnetic layers are alternately laminated, the magnetic layers mainly contain Fe, Co and Ni, and these main components The upper limit of the solid solution with respect to the element is 0.1 to 30 atom% of the additional element at room temperature, and the magnetoresistive effect film is characterized. 6. A magnetoresistive effect film having a spin valve structure in which a magnetic layer, a conductor layer and a magnetic layer are laminated in this order, wherein the magnetic layer contains Fe, Co and Ni as main components, and A magnetoresistive effect film characterized by containing 0.1 to 30 atom% of an additional element whose solid solution upper limit with respect to these main constituent elements is 1% or less at room temperature. 7. The additive element added to the magnetic layer is A
g, B, Bi, C, Co, Cr, Fe, Hg, Ir, L
7. The element selected from i, Mo, Na, Nb, Pb, V, Pt, and Zr.
The magnetoresistive film according to 1.