JP2003008110A - Spin valve thin film magnetic element and thin film magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spin valve thin film magnetic element that is excellent in heat resistance and corrosion resistance and provided with a bias structure in which the direction of magnetization of a free magnetic layer can be arranged properly. SOLUTION: The spin valve thin film magnetic element has an antiferromagnetic layer, a fixed magnetic layer, a free magnetic layer formed on the fixed magnetic layer through a nonmagnetic conductive layer, soft magnetic layers arranged on the free magnetic layer at the interval corresponding to a track width, bias layers formed on the soft magnetic layers, and conductive layers formed on the bias layers on a substrate. The antiferromagnetic layer and bias layers are composed of alloys expressed by the compositional formula of Ptm Mn100-m and the (m) indicating the percentage composition of the alloy constituting the bias layer is adjusted to meet 52 at.%<=m<=60 at.% and the (m) indicating the percentage composition of the alloy constituting the antiferromagnetic layer is adjusted to meet 48 at.%<=m<=58 at.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spin-valve type thin film magnetic element whose electric resistance changes depending on the relationship between the direction of fixed magnetization of a fixed magnetic layer and the direction of magnetization of a free magnetic layer affected by an external magnetic field. In particular, the present invention relates to a spin valve thin film magnetic element having excellent heat resistance and a thin film magnetic head including the spin valve thin film magnetic element.

[0002]

2. Description of the Related Art A magnetoresistive effect type magnetic head includes an AMR (Anisotropic Magn) equipped with an element exhibiting a magnetoresistive effect.
An etoresistive) head and a GMR (Giant Magnetoresistive) head including an element exhibiting a giant magnetoresistive effect are known. In the AMR head, the element exhibiting the magnetoresistive effect has a single layer structure made of a magnetic material. On the other hand, the GMR head is a multi-layer structure element formed by laminating a plurality of materials. There are several types of structures that produce the giant magnetoresistive effect, but the spin-valve thin-film magnetic element is known as having a relatively simple structure and a high resistance change rate with respect to a weak external magnetic field.

13 and 14 are sectional views showing the structure of an example of a conventional spin-valve thin film magnetic element when viewed from the side facing a recording medium. Shield layers are formed above and below the spin-valve thin-film magnetic element in these examples via a gap layer. The spin-valve thin-film magnetic element, the gap layer, and the shield layer form a GMR head for reproduction. It is configured. In addition, the G for reproduction
An inductive head for magnetic recording may be laminated on the MR head. This GMR head is provided with an inductive head for magnetic recording at the trailing side end of a floating slider to form a thin film magnetic head, and detects the recording magnetic field of a magnetic recording medium such as a hard disk. 13 and 14, the moving direction of the magnetic recording medium is the Z direction in the figure, and the direction of the leakage magnetic field from the magnetic recording medium is the Y direction.

The spin valve thin film magnetic element shown in FIG. 13 is a so-called bottom type single spin valve in which an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer and a free magnetic layer are formed in order from the substrate side. Type thin film magnetic element.
The spin-valve thin-film magnetic element shown in FIG. 13 has an underlayer 31, an antiferromagnetic layer 22, and a pinned magnetic layer 2 from the bottom of FIG.
3, a multilayer film 33 composed of the non-magnetic conductive layer 24, the free magnetic layer 25 and the protective layer 32, and a pair of hard bias layers (permanent magnet layers) 2 formed on both sides of the multilayer film 33.
9, 29, and a pair of electrode layers 28, 28 formed on the hard bias layers 29, 29. The base layer 31 and the protective layer 32 are formed of a Ta film or the like. Further, the track width Tw is determined by the width dimension of the upper surface of the multilayer film 9.

Generally, the antiferromagnetic layer 22 contains Fe--
A Mn alloy film or a Ni—Mn alloy film, a Ni—Fe alloy film for the fixed magnetic layer 23 and the free magnetic layer 25, a Cu film for the nonmagnetic conductive layer 24, and hard bias layers 29, 29.
Is a Co—Pt alloy film, and the electrode layers 28, 28 are Cr films or W films.

As shown in FIG. 13, the magnetization of the pinned magnetic layer 23 is made into a single magnetic domain in the Y direction (the direction of the leakage magnetic field from the recording medium: the height direction) by the exchange anisotropic magnetic field with the antiferromagnetic layer 22. Then, the magnetization of the free magnetic layer 25 is affected by the bias magnetic field from the hard bias layers 29, 29 and X
Aligned in one direction and the opposite direction. That is, the fixed magnetic layer 23
And the magnetization of the free magnetic layer 25 are set to be orthogonal to each other.

In this spin valve thin film element, the electrode layers 28, 28 formed on the hard bias layers 29, 29 are formed.
Therefore, a detection current (sense current) is applied to the pinned magnetic layer 23, the nonmagnetic conductive layer 24, and the free magnetic layer 25. The traveling direction of a magnetic recording medium such as a hard disk is the Z direction. When the leakage magnetic field direction from the magnetic recording medium is given in the Y direction, the magnetization of the free magnetic layer 25 changes from the direction opposite to the X1 direction to the Y direction. This free magnetic layer 2
5, the electric resistance changes due to the relationship between the change in the magnetization direction within 5 and the fixed magnetization direction of the fixed magnetic layer 23 (this is referred to as a change in the magnetic resistance). The stray magnetic field from the medium can be detected.

The spin-valve type thin film magnetic element shown in FIG. 14 has an antiferromagnetic layer in order from the substrate side (lower side of FIG. 14).
This is a so-called bottom type single spin valve thin film magnetic element in which a fixed magnetic layer, a non-magnetic conductive layer and a free magnetic layer are formed one by one.

In FIG. 14, reference numeral K indicates a substrate. An antiferromagnetic layer 22 is formed on the substrate K. Further, a fixed magnetic layer 23 is formed on the antiferromagnetic layer 22, a nonmagnetic conductive layer 24 is formed on the fixed magnetic layer 23, and further, a nonmagnetic conductive layer 24 is formed. A free magnetic layer 25 is formed on the. Bias layers 26, 26 are provided on the free magnetic layer 25 at the same intervals as the track width Tw, and conductive layers 28, 28 are provided on the bias layers 26, 26. There is.

The pinned magnetic layer 23 is, for example, a Co film,
It is formed of a NiFe alloy, a CoNiFe alloy, a CoFe alloy, or the like. The antiferromagnetic layer 22 is made of N
It is formed of an iMn alloy. The bias layer is formed of an antiferromagnetic material such as a FeMn alloy having a face-centered cubic crystal and an irregular crystal structure that does not require heat treatment for generating an exchange anisotropic magnetic field.

The pinned magnetic layer 23 shown in FIG. 14 is magnetized in one direction by an exchange anisotropic magnetic field due to exchange coupling generated at the interface with the antiferromagnetic layer 22. The magnetization direction of the fixed magnetic layer 23 is fixed in the Y direction shown in the figure, that is, in the direction away from the recording medium (height direction).

Further, the free magnetic layer 25 is magnetized by the exchange anisotropic magnetic field of the bias layer 26 to be made into a single magnetic domain. The magnetization direction of the free magnetic layer 25 is aligned with the direction opposite to the X1 direction in the figure, that is, the direction perpendicular to the magnetization direction of the pinned magnetic layer 23. Since the free magnetic layer 25 is made into a single magnetic domain by the exchange anisotropic magnetic field of the bias layer 26, Barkhausen noise is prevented from occurring.

In this conventional spin valve thin film magnetic element, a steady current is applied from the conductive layer 28 to the free magnetic layer 25, the nonmagnetic conductive layer 24 and the pinned magnetic layer 23, and Z
When the leakage magnetic field from the magnetic recording medium running in the direction is given along the Y direction in the drawing, the magnetization direction of the free magnetic layer 25 changes from the direction opposite to the X1 direction in the drawing toward the Y direction. The electric resistance changes due to the relationship between the variation of the magnetization direction in the free magnetic layer 25 and the magnetization direction of the fixed magnetic layer 23, and the leakage magnetic field from the magnetic recording medium is detected by the voltage change based on this resistance change.

In order to manufacture the spin-valve type thin film magnetic element as shown in FIG. 14, as shown in FIG. 15, the antiferromagnetic layer 2 is used.
Each layer from 2 to the free magnetic layer 25 is laminated and subjected to heat treatment (annealing) in a magnetic field to generate an exchange anisotropic magnetic field at the interface between the fixed magnetic layer 23 and the antiferromagnetic layer 22. After the magnetization direction of the pinned magnetic layer 23 is fixed in the Y direction shown in the drawing, a lift-off resist 351 having a width substantially corresponding to the track width is further formed as shown in FIG. Next, as shown in FIG. 17, a bias layer 26 and a conductive layer 28 are formed on the surface of the free magnetic layer 25 not covered by the lift-off resist 351, and the lift-off resist 351 is removed. By aligning the magnetization direction with the track width direction,
The spin-valve type thin film magnetic element having the magnetization direction shown in FIG.

Next, FIG. 18 is a cross-sectional view showing a structure of an example of a main part of a thin film magnetic head including a spin valve type thin film element of another conventional example, as viewed from the side facing a recording medium. It is a figure. In FIG. 18, reference numeral MR3 indicates a spin valve thin film element. In FIG. 18, reference numeral a1
2 is a laminated body. This laminated body a12 has a base layer 121.
The antiferromagnetic layer 122 is formed on the antiferromagnetic layer 122.
The fixed magnetic layer 153 is formed on the fixed magnetic layer 15 and
3, a nonmagnetic conductive layer 124 is formed, a free magnetic layer 175 is formed on the nonmagnetic conductive layer 124, and a protective layer 127 is further formed on the free magnetic layer 175.

The free magnetic layer 175 of the spin-valve type thin film element MR3 of this example comprises a non-magnetic intermediate layer 176, a first free magnetic layer 177 and a second free magnetic layer 178 sandwiching the non-magnetic intermediate layer 176. It consists of The first free magnetic layer 177 is provided on the protective layer 127 side of the nonmagnetic intermediate layer 176, and the second free magnetic layer 178 is provided on the nonmagnetic conductive layer 124 side of the nonmagnetic intermediate layer 176. The second free magnetic layer 178 is composed of the diffusion prevention layer 179 and the ferromagnetic layer 180.

The thickness t ₂ of the second free magnetic layer 178 is
It is formed to be thicker than the thickness t _{1 of} the first free magnetic layer 177. Further, when the saturation magnetizations of the first free magnetic layer 178 and the second free magnetic layer 178 are M ₁ and M ₂ , respectively, the magnetic films of the first free magnetic layer 177 and the second free magnetic layer 178. Thickness is M ₁ · t ₁ and M ₂ · t _{2 respectively}
Becomes Since the second free magnetic layer 178 is composed of the diffusion prevention layer 179 and the ferromagnetic layer 180, the magnetic film thickness M ₂ · t ₂ of the second free magnetic layer 178 is equal to that of the diffusion prevention layer 179. It is the sum of the magnetic film thickness and the magnetic film thickness of the ferromagnetic layer 180.

In the free magnetic layer 175, the first free magnetic layer 177 and the second free magnetic layer 1
The relationship between the magnetic film thickness and 78 is M ₂ · t ₂ > M ₁ · t ₁ . The first free magnetic layer 177 and the second free magnetic layer 178 are antiferromagnetically coupled to each other. That is, when the magnetization direction of the second free magnetic layer 178 is aligned in the X1 direction in the figure by the hard bias layers 126 and 126, the magnetization direction of the first free magnetic layer 177 is aligned in the opposite direction to the X1 direction in the figure.

The first and second free magnetic layers 17 described above are also used.
7, the magnetic film thickness relationship of M is 178 ₂・ T₂> M₁・ T₁When
Therefore, the magnetization of the second free magnetic layer 178 is
Remains, and the magnetization of the entire free magnetic layer 175 becomes
The directions are aligned with the X1 direction in the figure. Free porcelain at this time
The effective thickness of the conductive layer 175 is (M₂・ T₂-M₁・ T₁) Tosa
Be done. Thus, the first free magnetic layer 177 and the second free magnetic layer 177
The magnetization directions of the free magnetic layer 178 are antiparallel.
Antiferromagnetically coupled so as to be oriented and magnetic film thickness
Relationship is M₂・ T₂> M₁・ T₁Because it is said that
It is in an engineering ferrimagnetic state. This also allows
The magnetization direction of the free magnetic layer 175 and the magnetization of the fixed magnetic layer 153
There is a relationship that intersects with the changing direction.

[0020]

However, as shown in FIG.
In the conventional spin-valve thin-film magnetic element shown in (1), there is a possibility that the problems described below may occur. FIG.
As described above, the magnetization of the pinned magnetic layer 23 is pinned in the Y direction in the single magnetic domain, but is magnetized on both sides of the pinned magnetic layer 23 in the direction opposite to the X1 direction. Hard bias layers 29, 29 are provided. Therefore, in particular, the magnetizations on both sides of the pinned magnetic layer 23 are affected by the bias magnetic fields from the hard bias layers 29, 29, so that it is difficult to pin them in the Y direction in the drawing.

That is, under the influence of the magnetization of the hard bias layers 29, 29 in the direction opposite to the X1 direction, the magnetization of the free magnetic layer 25 which is made into a single magnetic domain in the direction opposite to the X1 direction and the fixed magnetic layer 23. The magnetization is not likely to be orthogonal to each other particularly near the side end of the multilayer film 33. The reason why the magnetization of the free magnetic layer 25 and the magnetization of the pinned magnetic layer 23 are set to be orthogonal to each other is that the magnetization of the free magnetic layer 25 can be easily changed even with a small external magnetic field, and the electric resistance can be largely changed. This is because the reproduction sensitivity can be improved. Furthermore, if the magnetizations are in an orthogonal relationship, it is possible to obtain an output waveform having good symmetry.

In addition, the magnetization of the free magnetic layer 25 near the side end portion thereof is hard bias layers 29, 29.
It tends to be fixed unnecessarily due to the influence of strong magnetization from the magnetic field, and the magnetization is less sensitive to fluctuations in the external magnetic field. As shown in FIG.
A dead region having poor reproduction sensitivity is formed in the vicinity of the side end of the No. 3 side.

The central region of the multilayer film 33 excluding the dead region is a sensitivity region that substantially contributes to reproduction of the recording magnetic field and exerts a magnetoresistive effect, and the width of this sensitivity region is The track width Tw set when the multilayer film 33 is formed is shorter than the track width Tw by the width dimension of the dead region.
Variations in dead areas make it difficult to define an accurate track width. Therefore, there is a problem that it is difficult to reduce the track width and cope with high recording density.

In the spin-valve type thin film magnetic element shown in FIG. 14, the magnetization direction of the free magnetic layer is set to the magnetization direction of the fixed magnetic layer by the exchange bias method using a bias layer made of an antiferromagnetic material. They are aligned in the direction intersecting at 90 °. The exchange bias method is a method suitable for a spin-valve thin film magnetic element corresponding to high-density recording with a narrow track width, as compared with a hard bias method in which it is difficult to control the effective track width due to a dead zone. .

However, in the spin valve thin film magnetic element shown in FIG. 14, the antiferromagnetic layer 22 is made of Ni-M.
Since it is formed of an n alloy, there is a problem in corrosion resistance. Further, the antiferromagnetic layer 22 has a Ni-Mn alloy or Fe-Mn.
In a spin valve thin film magnetic element using an alloy, it is corroded by a weak alkaline solution or emulsifier containing sodium tripolyphosphate exposed in the manufacturing process of the thin film magnetic head,
There is a problem that the exchange anisotropic magnetic field becomes small.

Further, since the antiferromagnetic layer 22 is formed of a Ni-Mn alloy, there are restrictions on the antiferromagnetic material used for the bias layers 26, 26, and as a result, the heat resistance of the bias layers 26, 26 is limited. There was a disadvantage that the corrosion resistance and the corrosion resistance were poor. That is, in order to form the bias layers 26, 26 having high heat resistance, the antiferromagnetic layer 22 made of a Ni—Mn alloy is used.
At the interface between the pinned magnetic layer 23 and the pinned magnetic layer 23, heat treatment is applied in a magnetic field in a direction intersecting with an exchange anisotropic magnetic field acting in the Y direction shown in the drawing, so that the bias layers 26, 26 and the free magnetic layer 2 are formed.
At the interface of No. 5, an antiferromagnetic material such as a Ni—Mn alloy capable of generating an exchange anisotropic magnetic field in the direction opposite to the X1 direction must be selected.

However, when the heat treatment is performed in the magnetic field, the exchange anisotropic magnetic field acting on the interface between the antiferromagnetic layer 22 and the pinned magnetic layer 23 is inclined from the Y direction to the direction opposite to the X1 direction, and the fixed magnetic field is generated. There is a problem that the magnetization direction of the layer 23 and the magnetization direction of the free magnetic layer 25 are non-orthogonal, and the symmetry of the output signal waveform cannot be obtained. Therefore, the bias layers 26, 26 do not require heat treatment in a magnetic field,
It was necessary to select an antiferromagnetic material that generates an exchange anisotropic magnetic field immediately after film formation in a magnetic field. For this reason,
The bias layers 26, 26 are generally formed of a FeMn alloy having a face-centered cubic crystal and an irregular crystal structure.

However, when it is mounted on a magnetic recording device or the like, the temperature of the element portion becomes 100 due to the temperature rise in the device or the generation of Joule heat generated by the detected current.
Since the temperature exceeds ℃, the exchange anisotropic magnetic field decreases,
It is difficult to form the free magnetic layer 25 into a single magnetic domain, and as a result, Barkhausen noise is generated. Further, the Fe-Mn alloy has poorer corrosion resistance than the Ni-Mn alloy, and is corroded by a weak alkaline solution or emulsifier containing sodium tripolyphosphate exposed in the manufacturing process of the thin-film magnetic head, resulting in an exchange anisotropic magnetic field. Not only has a problem that the magnetic field becomes smaller, but also has a problem that the corrosion progresses even in the magnetic recording device, resulting in poor durability.

Further, in the conventional method for manufacturing a spin-valve thin film magnetic element shown in FIGS. 15 to 17, in the step of forming the lift-off resist 351 shown in FIG. 16, a space between the substrate and the bias layer is formed. Since the surface of the uppermost layer formed in 1) is exposed to the atmosphere, it is necessary to clean the surface exposed to the atmosphere by ion milling or reverse sputtering with a rare gas such as Ar before forming the layer thereon. Therefore, there is a problem that the number of manufacturing processes increases. Furthermore, since it is necessary to clean the surface of the uppermost layer by ion milling or reverse sputtering, contamination due to redeposited matter,
Inconveniences caused by cleaning occur, such as adverse effects on the generation of the exchange anisotropic magnetic field due to the disorder of the crystal state of the surface.

Further, in the spin valve thin film element MR3 shown in FIG. 18, the tip portions 126a of the hard bias layers 126, 126 near the upper end of the side surface of the laminated body a12,
The magnetic field applied to the first free magnetic layer 177 from 126a is strong, and this magnetic field is generated by the first free magnetic layer 177.
Therefore, when the magnetic field of the hard bias layers 126 and 126 becomes larger than the spin-flop magnetic field (H _sf ) described later, the magnetic field direction originally desired to be applied to the first free magnetic layer 177 is A magnetic field in the direction opposite to that of the first free magnetic layer 177 is applied to both ends (the vicinity of each hard bias layer 126) of the first free magnetic layer 177, and the magnetization direction in the central portion of the first free magnetic layer 177 is the second direction. Although the free magnetic layer 178 is aligned in the opposite direction of the magnetization direction (the opposite direction of the X1 direction), there is a problem that the magnetization direction is disturbed at both ends.

When the magnetization directions of both ends of the first free magnetic layer 177 are disturbed in this way, the magnetization direction is antiparallel to the magnetization direction of the first free magnetic layer 177 (X1 direction).
In the second free magnetic layer 178 which is aligned with the first free magnetic layer 177, the magnetization direction of the central portion is opposite to the magnetization direction of the first free magnetic layer 177 (X1 direction). It is disturbed and the first and second free magnetic layers 17 are disturbed.
As a result of the magnetization directions of both ends of Nos. 7 and 178 not aligning in antiparallel, the reproduction waveform becomes unstable at both ends of the track width Tw, which may cause a problem such as a servo error.

Next, the spin-flop magnetic field will be described with reference to FIG. FIG. 19 shows M− of the free magnetic layer.
It is a figure which shows a H curve. This MH curve is the change in the magnetization M of the free magnetic layer 175 when an external magnetic field H is applied to the free magnetic layer 175 of the spin-valve thin film element MR3 having the configuration shown in FIG. 19 from the track width direction. Is shown. In FIG. 19, the external magnetic field H corresponds to the bias magnetic field from the hard bias layers 126, 126.

Further, in FIG. 19, the arrow indicated by F ₁ indicates the magnetization direction of the first free magnetic layer 177, and F ₂
The arrow indicated by indicates the magnetization direction of the second free magnetic layer 178. As shown in FIG. 19, when the external magnetic field H is small, the first free magnetic layer 177 and the second free magnetic layer 1 are
78 is antiferromagnetically coupled, that is, the directions of the arrows F ₁ and F ₂ are antiparallel, but when the magnitude of the external magnetic field H exceeds a certain value, the arrows F ₁ and F 2 The directions of ₂ are not aligned antiparallel, the antiferromagnetic coupling between the first free magnetic layer 177 and the second free magnetic layer 178 is broken, and the ferrimagnetic state cannot be maintained. This is the spin-flop transition. The magnitude of the external magnetic field when this spin-flop transition occurs is the spin-flop magnetic field, which is indicated by H _sf in FIG. Then, when the external magnetic field H is further made larger than the spin-flop magnetic field H _sf , the direction of the arrow F ₁ further rotates, and the direction parallel to the direction of the arrow F ₂ is turned,
That is, the arrow F ₁ points in a direction different from the original direction by 180 °, and the ferrimagnetic state is completely destroyed. This is the saturation magnetic field, which is indicated by H _S in FIG.

Therefore, the directions of magnetization at both ends of the first and second free magnetic layers 177 and 178 in FIG. 19 are present in the region of the first free magnetic layer 177 shown by the arrow F ₁ in FIG. 20, for example. As shown by various arrows, the first free magnetic layer 177 is disturbed more greatly at both ends thereof.
The magnetization that tends to be in the anti-parallel state of the ferri state with respect to the direction of the magnetization of the free magnetic layer 177 has a relationship such that it is oriented in the direction of the region of the second free magnetic layer 178 shown by the arrow F ₂ in FIG. I will end up. Therefore, also in the spin-valve type thin film element MR3 having the structure shown in FIG. 18, there is a possibility of causing instability in the reproduced waveform at both ends of the track width Tw and causing a problem such as a servo error. The magnetization state shown in FIG. 20 will be described in more detail. On the left and right ends of the first free magnetic layer 177, a strong reverse magnetic field from the hard bias layer is applied, so that the magnetization distribution of the second free magnetic layer 178 is also increased. Disturbance may occur and Barkhausen noise or the like may occur, which causes concern about magnetic stability.

The present invention has been made to solve the above problems, and provides a spin valve thin film magnetic element excellent in heat resistance and corrosion resistance by improving the material of the bias layer. An object of the present invention is to provide a spin-valve thin film magnetic element having a bias structure capable of surely aligning the magnetization directions of the free magnetic layer. Further, according to the present invention, the structure in which the free magnetic layer is separated into two layers is adopted, and even if the structure in which the bias is applied to the free magnetic layer is adopted, the disturbance of the magnetization occurs on the end side of each free magnetic layer. An object of the present invention is to provide a spin-valve thin-film magnetic element that has a structure that allows a bias to act well and that suppresses the occurrence of Barkhausen noise and that has improved stability.

Furthermore, it is another object of the present invention to provide a thin film magnetic head having the spin-valve type thin film magnetic element, which is excellent in durability and heat resistance and which can obtain a sufficient exchange anisotropic magnetic field and has high reliability.

[0037]

In order to achieve the above object, the present invention has the following constitutions. A spin-valve thin-film magnetic element of the present invention is an antiferromagnetic layer, and a pinned magnetic layer formed on the antiferromagnetic layer and having a magnetization direction fixed by an exchange anisotropic magnetic field with the antiferromagnetic layer. A free magnetic layer formed on the pinned magnetic layer via a non-magnetic conductive layer, a soft magnetic layer arranged in contact with the free magnetic layer with a gap corresponding to a track width, and the soft magnetic layer. A bias layer formed in contact with the magnetic layer, which aligns the magnetization direction of the free magnetic layer in a direction intersecting the magnetization direction of the pinned magnetic layer, and a conductive layer which gives a detection current to the free magnetic layer are formed on the substrate. A spin-valve thin-film magnetic element having
The antiferromagnetic layer and the bias layer have a composition formula Pt.
_m Mn _100-m , which is composed of alloys having different composition ratios, in which _m representing the composition ratio of the alloy forming the bias layer is 52 atom% ≦ m ≦ 60 atom%, and forming the antiferromagnetic layer Indicating the composition ratio of the alloy to be used, m is 48 atomic% ≤ m ≤ 58 atomic%
It is characterized by being. It is more preferable that m representing the composition ratio of the bias layer is 52 at% ≦ m ≦ 54 at%. It is more preferable that m representing the composition ratio of the bias layer is 56.8 atom% ≦ m ≦ 60 atom%.

In such a spin-valve thin-film magnetic element, since the antiferromagnetic layer and the bias layer are made of the above alloy, the temperature characteristic of the exchange anisotropic magnetic field becomes good, and the heat resistance and corrosion resistance are improved. It is possible to provide an excellent spin valve thin film magnetic element. Also, the spin valve type is excellent in durability when equipped in a device such as a thin film magnetic head whose temperature in the device becomes high, and has little fluctuation of exchange anisotropic magnetic field (exchange coupling magnetic field) due to temperature change. A thin film magnetic element can be obtained. Furthermore, by forming the antiferromagnetic layer with the above alloy, the blocking temperature becomes high, and a large exchange anisotropic magnetic field can be generated in the antiferromagnetic layer, so that the magnetization direction of the pinned magnetic layer is changed. Can be firmly fixed. Moreover, since the soft magnetic layer is formed between the free magnetic layer and the bias layer, the magnetization directions of the free magnetic layer can be reliably aligned.

Further, in the above spin-valve thin film magnetic element, at least one of the pinned magnetic layer and the free magnetic layer is divided into two via a non-magnetic intermediate layer,
The separated layers may be in a ferrimagnetic state in which the magnetization directions are antiparallel.

In the case of a spin valve thin film magnetic element in which at least the pinned magnetic layer is divided into two via a non-magnetic intermediate layer, one of the two pinned magnetic layers is the other pinned magnetic layer. It plays a role of fixing in the proper direction, and it becomes possible to keep the state of the fixed magnetic layer in a very stable state. On the other hand, when at least the free magnetic layer is divided into two via the non-magnetic intermediate layer to form a spin-valve thin-film magnetic element, an exchange coupling magnetic field is generated between the two divided free magnetic layers, and the ferrimagnetic field is reduced. It is brought into a magnetic state and can be inverted with high sensitivity to an external magnetic field.

In the above spin-valve type thin film magnetic element, it is desirable that the soft magnetic layer is made of a NiFe alloy.

In the present invention, recesses are formed on both sides of a portion corresponding to the track width of the free magnetic layer, and soft magnetic layers are laminated so as to fill these recesses. These soft magnetic layers serve as the free magnetic layer. A structure may be adopted in which the soft magnetic layer is directly bonded to the bottom surface of the recess and a bias layer and a conductive layer are laminated on these soft magnetic layers. In general, the exchange coupling at the interface between the ferromagnetic material and the antiferromagnetic material is more likely to be adversely affected by contamination at the interface and disorder of crystallinity than the exchange coupling at the interface between the ferromagnetic material and the ferromagnetic material.
Therefore, it is necessary to continuously form the soft magnetic layer and the bias layer in the same film forming apparatus. When a soft magnetic layer is formed without forming a recess in the free magnetic layer, the total (ferromagnetic film thickness x saturation magnetization) of both sides of the track width is less than the (ferromagnetic film thickness x saturation magnetization) of the free magnetic layer. Significantly thicker. The strength of the longitudinal bias received by the free magnetic layer is proportional to the value obtained by dividing (ferromagnetic film thickness x saturation magnetization) at both ends of the track by (ferromagnetic film thickness x saturation magnetization) of the free magnetic layer. If it is not provided, the longitudinal bias may become excessively strong, resulting in problems such as dead zones at both ends of the track and a decrease in sensitivity of the entire device.
Also, if the soft magnetic layer is made too thick, the exchange coupling magnetic field between the bias layer and the soft magnetic layer decreases in inverse proportion to the film thickness, so the longitudinal bias state changes due to a slight disturbance magnetic field and the reproduction waveform becomes unstable. It is also possible that a problem such as being linked to These can be improved by making the thickness of the soft magnetic layer as thin as possible. However, if the soft magnetic layer is made too thin, the soft magnetic layer cannot maintain sufficient crystallinity, and so on. On the contrary, there is a problem that the exchange coupling magnetic field deteriorates. When the recess is provided, the thickness of the soft magnetic layer added by the depth of the recess is partially offset, so that the longitudinal bias is less likely to be stronger than necessary and the exchange coupling between the soft magnetic layers is not required. Since the magnetic field does not easily decrease, the read sensitivity, the controllability of the track width, and the stability of the read waveform are improved. As a second effect, by digging the concave portion by ion milling or the like, contaminants on the surface of the free magnetic layer can be effectively removed, and the ferromagnetic exchange coupling between the soft magnetic layer and the free magnetic layer is further strengthened. It also has an effect of effectively transmitting the longitudinal bias to the free magnetic layer. Also,
Even when a backed layer such as Cu or an anti-oxidation layer such as Ta is laminated on the free magnetic layer, the concave portion is dug to surely expose the surface of the ferromagnetic material forming the free magnetic layer. be able to.

Further, in the present invention, the free magnetic layer is divided into two via a non-magnetic intermediate layer, and the free magnetic layer far from the pinned magnetic layer is the first free magnetic layer and the pinned magnetic layer. When the free magnetic layer close to the layer is the second free magnetic layer, the magnetic thickness of the first free magnetic layer is different from the magnetic thickness of the second free magnetic layer. A structure characterized by being formed may be adopted.

FIG. 21 is a graph showing the relationship between the heat treatment temperature of the antiferromagnetic layer and the exchange anisotropic magnetic field in the bottom spin valve thin film magnetic element and the top spin valve thin film magnetic element. As is clear from FIG. 21, the antiferromagnetic layer of the bottom spin-valve thin-film magnetic element in which the antiferromagnetic layer and the substrate are close (or the antiferromagnetic layer is arranged under the fixed magnetic layer). The exchange anisotropic magnetic field of (■) is 2
It has already developed at 00 ° C and exceeds 600 (Oe) at around 240 ° C. On the other hand, the distance between the antiferromagnetic layer and the substrate is larger than that of the bottom spin valve thin film magnetic element (or the antiferromagnetic layer is arranged on the fixed magnetic layer) of the top spin valve thin film magnetic element. The exchange anisotropic magnetic field of the antiferromagnetic layer (marked with ♦) appears near 240 ° C., and exceeds 600 Oe (48000 A / m) at around 260 ° C.

As described above, the antiferromagnetic layer of the bottom type spin-valve thin film magnetic element in which the distance between the antiferromagnetic layer and the substrate is short (or the antiferromagnetic layer is arranged under the pinned magnetic layer) is , The distance between the antiferromagnetic layer and the substrate is farther than the bottom spin valve thin film magnetic element (or the antiferromagnetic layer is arranged on the fixed magnetic layer) compared to the top spin valve thin film magnetic element Then, it can be seen that a high exchange anisotropic magnetic field can be obtained at a relatively low heat treatment temperature.

In the spin valve thin film magnetic element, in the case of the bottom type spin valve thin film magnetic element in which the distance between the antiferromagnetic layer and the substrate is short, it is formed of the same material as that used for the antiferromagnetic layer. The bias layer is located farther from the substrate than the antiferromagnetic layer. Further, in a bottom-type spin-valve thin-film magnetic element in which the fixed magnetic layer and the substrate are close to each other, an antiferromagnetic layer is arranged below the fixed magnetic layer, and the distance between the antiferromagnetic layer and the substrate is the bottom-type spin-valve. In a top spin valve thin film magnetic element farther than the valve thin film magnetic element, an antiferromagnetic layer is arranged on a pinned magnetic layer.

Therefore, for example, in a method of manufacturing a spin valve thin film magnetic element, while applying the first magnetic field,
When the first stacked body is heat-treated at the first heat treatment temperature (220 to 270 ° C.), an exchange anisotropic magnetic field is generated in the antiferromagnetic layer, and the magnetization directions of the pinned magnetic layers are fixed in the same direction. The exchange anisotropic magnetic field of the antiferromagnetic layer is 600 (Oe) or more. Next, the second heat treatment temperature (250 to 270 ° C.) is applied while applying the second magnetic field 10 to 600 Oe (800 to 48000 A / m) in the direction orthogonal to the first magnetic field.
Then, when the second laminated body is heat-treated, an exchange anisotropic magnetic field of the bias layer is generated, and the magnetization direction of the free magnetic layer intersects with the first magnetic field. The exchange anisotropic magnetic field of the bias layer is 600 Oe (48000 A /
m) or more.

At this time, if the second magnetic field is made smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer generated in the first heat treatment, the second magnetic field is applied to the antiferromagnetic layer. Even if
The exchange anisotropic magnetic field of the antiferromagnetic layer does not deteriorate, and the magnetization direction of the pinned magnetic layer can be kept fixed. This allows the magnetization direction of the pinned magnetic layer and the magnetization direction of the free magnetic layer to intersect each other.

Therefore, in the above method for manufacturing the spin-valve type thin film magnetic element, PtMn excellent in heat resistance is used.
An alloy such as an alloy is used not only for the antiferromagnetic layer but also for the bias layer, and the magnetization direction of the free magnetic layer is set to the bias layer with respect to the magnetization direction of the pinned magnetic layer without adversely affecting the magnetization direction of the pinned magnetic layer. It is possible to generate an exchange anisotropic magnetic field that aligns in the direction that intersects with the magnetic field, and the magnetization direction of the free magnetic layer can be aligned in the direction that intersects the magnetization direction of the pinned magnetic layer. It is possible to provide a valve type thin film magnetic element.

In the method of manufacturing the spin-valve thin film magnetic element, the soft magnetic layer is formed on the first laminated body, and the bias layer is formed on the soft magnetic layer. After the soft magnetic layer is formed, the bias layer can be formed without breaking the vacuum, and it is not necessary to clean the surface on which the bias layer is formed by ion milling or reverse sputtering. It is possible to provide an excellent manufacturing method that does not cause inconveniences caused by cleaning, such as contamination and adverse effects on the generation of an exchange anisotropic magnetic field due to disturbance of the crystal state of the surface. In addition, since it is not necessary to clean the surface on which the bias layer is formed before forming the bias layer, it can be easily manufactured.

The thin-film magnetic head of the present invention is characterized in that the slider is provided with the above spin-valve thin-film magnetic element. By using such a thin film magnetic head, it is possible to obtain a highly reliable thin film magnetic head that has excellent durability, heat resistance, and corrosion resistance, and that can obtain a sufficient exchange anisotropic magnetic field.

[0052]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the spin valve thin film magnetic element of the present invention will be described below in detail with reference to the drawings. [First Embodiment] FIG. 1 is a sectional view showing the structure of a spin valve thin film magnetic element according to a first embodiment of the present invention when viewed from the side facing a recording medium, FIG. 5 and FIG. Figure 6
FIG. 3 is a diagram showing a thin film magnetic head including a spin valve thin film magnetic element of the present invention.

Shield layers are formed above and below the spin-valve thin-film magnetic element of the present invention via a gap layer. The spin-valve thin-film magnetic element, the gap layer, and the shield layer constitute a reproducing GMR head h1. It is configured. The recording inductive head h2 may be laminated on the reproducing GMR head h1.

As shown in FIG. 5, the GMR head h1 including this spin-valve type thin film magnetic element is provided at the trailing end 151d of the slider 151 together with the inductive head h2 to form the thin film magnetic head 150. However, it is possible to detect the recording magnetic field of a magnetic recording medium such as a hard disk. In FIG. 1, the moving direction of the magnetic recording medium is the Z direction in the figure, and the direction of the leakage magnetic field from the magnetic recording medium is the Y direction.

The thin film magnetic head 150 shown in FIG. 5 is mainly composed of a slider 151, and a GMR head h1 and an inductive head h2 provided on the end surface 151d of the slider 151. Reference numeral 155 denotes the slider 1
Reference numeral 156 indicates a leading side which is an upstream side in the moving direction of the magnetic recording medium, and reference numeral 156 indicates a trailing side. Rails 151a, 151a, 151b are formed on the medium facing surface 152 of the slider 151, and air grooves 151c, 151c are formed between the rails.

As shown in FIG. 6, the GMR head h1 is
Al ₂ O ₃ formed on the end surface 151d of the slider 151
A base layer 200 made of a non-magnetic insulator, and a base layer 2
00, a lower shield layer 163 made of a magnetic alloy, a lower gap layer 164 laminated on the lower shield layer 163, the spin valve thin film magnetic element 1 exposed from the medium facing surface 152, and a spin valve type. The upper gap layer 1 covering the thin film magnetic element 1 and the lower gap layer 164.
66 and the upper shield layer 1 covering the upper gap layer 166.
And 67. The upper shield layer 167 is
It is also used as the lower core layer of the inductive head h2.

The inductive head h2 has a lower core layer (upper shield layer) 167, a gap layer 174 laminated on the lower core layer 167, a coil 176, and a coil 1.
It is composed of an upper insulating layer 177 covering 76 and an upper core layer 178 bonded to the gap layer 174 and bonded to the lower core layer 167 on the coil 176 side. The coil 176 is patterned to have a spiral shape in a plane. Further, the base end portion 178b of the upper core layer 178 is magnetically connected to the lower core layer 167 at substantially the center of the coil 176. In addition, the upper core layer 178 includes
A protective layer 179 made of alumina or the like is laminated.

Spin valve thin film magnetic element 1 shown in FIG.
Is a so-called bottom type single spin valve thin film magnetic element in which an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer are formed one by one. In the spin-valve thin-film magnetic element 1 of this example, the magnetization direction of the free magnetic layer is aligned with the magnetization direction of the pinned magnetic layer by the exchange bias method using an antiferromagnetic material as the bias layer. It is a thing. The exchange bias method is suitable for a spin-valve thin film magnetic element with a narrow track width that is compatible with high density recording, as compared with a hard bias method in which it is difficult to control the effective track width due to a dead zone. .

In FIG. 1, reference numeral K indicates a substrate. The antiferromagnetic layer 2 is formed on the substrate K. Further, a fixed magnetic layer 3 is formed on the antiferromagnetic layer 2, and a nonmagnetic conductive layer 4 is formed on the fixed magnetic layer 3.
And a free magnetic layer 5 is formed on the nonmagnetic conductive layer 4. Soft magnetic layers 7, 7 are provided on the free magnetic layer 5 with an interval corresponding to the track width Tw. Bias layers 6 and 6 are provided on the soft magnetic layers 7 and 7, and conductive layers 8 and 8 are formed on the bias layers 6 and 6.

The substrate K has a surface of Al ₂ O ₃ —TiC ceramics 151 or the like and a non-magnetic insulator Al ₂ O.
_A base layer 200 made of ₃ (alumina) is formed, and a lower shield layer 163 and a lower gap layer 164 are sequentially formed on the base layer 200.

The antiferromagnetic layer 2 is made of Pt, Pd, Ir,
Rh, Ru, Os, Au, Ag, Cr, Ni, Ne, A
It is made of an alloy containing Mn and at least one or more elements of r, Xe, and Kr. The antiferromagnetic layer 2 made of these alloys is characterized by excellent heat resistance and corrosion resistance. In particular, the antiferromagnetic layer 2
Is preferably an alloy having the following composition formula. X _m Mn _100-m where X is at least one element selected from Pt, Pd, Ir, Rh, Ru and Os, and represents a composition ratio m.
Is 48 atom% ≦ m ≦ 60 atom%.

Further, the antiferromagnetic layer 2 may be an alloy having the following composition formula. Pt _m Mn _100-mn D _n where D is at least one element or two or more elements of Pd, Ir, Rh, Ru and Os, and m and n showing the composition ratio are 48 atomic% ≤ m + n ≦ 60 atomic%, 0.2 atomic% ≦ n ≦ 40 atomic%.

In the above spin-valve type thin film magnetic element, it is desirable that the antiferromagnetic layer is an alloy having the following composition formula. Pt _q Mn _100-qj L _j where L is Au, Ag, Cr, Ni, Ne, Ar, X
e and Kr are at least one element or two or more elements, and q and j, which represent the composition ratio, are 48 atom% ≦ q + j ≦.
60 atomic%, 0.2 atomic% ≦ j ≦ 10 atomic%. Further, q and j indicating the composition ratio are 48 atomic% ≦ q + j ≦ 58.
It is more preferable that atomic% and 0.2 atomic% ≦ j ≦ 10 atomic%.

The pinned magnetic layer 3 is, for example, a Co film or N film.
iFe alloy, CoNiFe alloy, CoFe alloy, CoN
It is made of an i alloy or the like. Pinned magnetic layer 3 shown in FIG.
Is formed in contact with the antiferromagnetic layer 2 and subjected to heat treatment in a magnetic field to magnetize by an exchange anisotropic magnetic field due to exchange coupling generated at the interface between the fixed magnetic layer 3 and the antiferromagnetic layer 2. Has been done. The magnetization direction of the fixed magnetic layer 3 is the Y direction in the figure, that is, the direction away from the recording medium (height direction).
It is fixed to.

The nonmagnetic conductive layer 4 is made of Cu, A
It is preferably formed of a non-magnetic conductive film such as u or Ag.

The free magnetic layer 5 is preferably made of the same material as the pinned magnetic layer 3.
The free magnetic layer 5 is magnetized by the bias magnetic field from the bias layer 6, and the magnetization direction is aligned in the direction opposite to the X1 direction in the drawing, that is, in the direction intersecting the magnetization direction of the pinned magnetic layer 3. Since the free magnetic layer 5 is formed into a single magnetic domain by the bias layer 6, Barkhausen noise is prevented from occurring.

The soft magnetic layer 7 is made of Co, Ni, Fe, C.
o-Fe alloy, Co-Ni-Fe alloy, CoNi alloy,
The free magnetic layer 5 is formed of a NiFe alloy or the like.
It is preferable that the soft magnetic layer 7 is formed of the same alloy as that of the above-mentioned material. If the surface of the free magnetic layer 5 is formed of a NiFe alloy, the soft magnetic layer 7 is preferably formed of a NiFe alloy. This is because when the soft magnetic layer 7 is made of the same material as that of the free magnetic layer 5, the ferromagnetic coupling at the interface between the soft magnetic layer 7 and the free magnetic layer 5 is ensured, and the bias layer 6 and the soft magnetic layer 5 are formed. The unidirectional anisotropic exchange coupling magnetic field generated at the interface with the layer 7 can be propagated to the free magnetic layer 5 via the soft magnetic layer 7.

The bias layer 6 is similar to the antiferromagnetic layer 2 in that Pt, Pd, Ir, Rh, Ru, Os, Au,
It is composed of an alloy containing Mn and at least one element of Ag, Cr, Ni, Ne, Ar, Xe, and Kr, and an interface with the soft magnetic layer 7 by heat treatment in a magnetic field. The exchange anisotropy magnetic field is developed at, the exchange anisotropy magnetic field propagates to the soft magnetic layer 7, and the free magnetic layer 5 is formed by the ferromagnetic coupling generated at the interface between the soft magnetic layer 7 and the free magnetic layer 5. It is magnetized in a fixed direction. The bias layer 6 made of these alloys is characterized by excellent heat resistance and corrosion resistance.

Particularly, the bias layer 6 is preferably an alloy having the following composition formula. X _m Mn _100-m where X is at least one element selected from Pt, Pd, Ir, Rh, Ru and Os, and represents a composition ratio m.
Is 52 atomic% ≦ m ≦ 60 atomic%. Further, the bias layer 6 may be an alloy having the following composition formula. Pt _m Mn _100-mn D _n However, D is at least 1 type or 2 or more types of elements of Pd, Ir, Rh, Ru, Os, and m and n which show a composition ratio are 52 atomic% <= m + n ≦ 60 atomic%, 0.2 atomic% ≦ n ≦ 40 atomic%.

Furthermore, in the above spin-valve type thin film magnetic element, the bias layer may be an alloy having the following composition formula. Pt _q Mn _100-qj L _j where L is Au, Ag, Cr, Ni, Ne, Ar, X
e and Kr are at least one element or two or more elements, and q and j showing the composition ratio are 52 atomic% ≦ q + j ≦
60 atomic%, 0.2 atomic% ≦ j ≦ 10 atomic%. The conductive layers 8 and 8 are made of, for example, Au, W, Cr, T
It is preferably formed of a or the like.

In this spin-valve thin-film magnetic element 1, a steady current is applied from the conductive layers 8 to the free magnetic layer 5, the non-magnetic conductive layer 4, and the fixed magnetic layer 3 to cause magnetic recording traveling in the Z direction in the figure. When the leakage magnetic field from the medium is applied in the Y direction in the drawing, the magnetization direction of the free magnetic layer 5 changes from the direction opposite to the X direction in the drawing toward the Y direction in the drawing. The electric resistance changes due to the relationship between the fluctuation of the magnetization direction in the free magnetic layer 5 and the magnetization direction of the fixed magnetic layer 3, and the leakage magnetic field from the magnetic recording medium is detected by the voltage change based on this resistance change.

Next, a method of manufacturing the spin valve thin film magnetic element 1 of the present invention will be described. According to this manufacturing method, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 and the bias layers 6 and 6 generated by the heat treatment depends on the positions of the antiferromagnetic layer 2 and the bias layers 6 and 6 in the spin-valve thin film magnetic element 1. It was made by using the property that the sizes are different,
By the first heat treatment, the magnetization direction of the pinned magnetic layer 3 is fixed and 2
By the second heat treatment, the magnetization direction of the free magnetic layer 5 is aligned with the magnetization direction of the pinned magnetic layer 3.

That is, in the method of manufacturing the spin-valve thin film magnetic element 1 of the present invention, the antiferromagnetic layer 2, the pinned magnetic layer 3, the nonmagnetic conductive layer 4, and the free magnetic layer 5 are formed on the substrate K. 2 are sequentially laminated to form a first laminated body a1 shown in FIG. 2, and then a first magnetic field in a direction orthogonal to the track width Tw direction (direction perpendicular to the paper surface of FIG. 2) is formed on the first laminated body a1. Is applied and heat treatment is performed at a first heat treatment temperature to generate an exchange anisotropic magnetic field in the antiferromagnetic layer 2 to generate the pinned magnetic layer 3.
Fix the magnetization of.

Next, as shown in FIG. 3, a lift-off resist 351 having a base end portion having a width corresponding to the track width Tw is formed on the first laminated body a1 to serve as a mask for lift-off. The surface of the free magnetic layer 5 not covered with the resist 351 is cleaned with a rare gas such as Ar by an ion milling method or a reverse sputtering method. Next, as shown in FIG. 4, soft magnetic layers 7 and 7 are formed on the surface of the free magnetic layer 5 exposed at intervals corresponding to the track width Tw and on the lift-off resist 351, and then the soft magnetic layers 7 and 7 are formed. Bias layers 6 and 6 are formed on the layers 7 and 7, and conductive layers 8 and 8 are further formed on the bias layers 6 and 6.
Then, the lift-off resist 351 is removed by etching to obtain a second stacked body a2 having the same shape as the spin-valve thin-film magnetic element 1 shown in FIG.

The second laminated body a2 thus obtained
On the other hand, while applying the second magnetic field smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 2 in the track width Tw direction,
By applying a bias magnetic field to the free magnetic layer 5 in a direction intersecting with the magnetization direction of the pinned magnetic layer 3, the spin valve thin film magnetic element 1
Is obtained.

Next, the relationship between the heat treatment temperature of the antiferromagnetic layer and the exchange anisotropic magnetic field will be described in detail with reference to FIGS. 21, 22 and 23. 21 indicates the heat treatment temperature dependence of the exchange anisotropy field of the bottom type single spin valve thin film magnetic element in which the antiferromagnetic layer is arranged between the substrate and the free magnetic layer, and is shown in FIG. The ♦ mark indicates the heat treatment temperature dependence of the exchange anisotropic magnetic field of the top-type single spin-valve thin film magnetic element in which the antiferromagnetic layer is arranged farther from the substrate than the free magnetic layer. Therefore, the antiferromagnetic layer of the top-type single-spin-valve thin-film magnetic element indicated by ◆ is located farther from the substrate than the antiferromagnetic layer of the bottom-type single-spin-valve thin-film magnetic element indicated by ■. become.

Specifically, as shown in FIG. 24, the top spin valve thin film magnetic element shown by the ♦ mark is made of Al ₂ O ₃ (thickness 1000Å) on the Si substrate K as shown in FIG.
A free magnetic layer 5 consisting of two layers: a base insulating layer 200 made of Ta, a base layer 210 made of Ta (thickness 50Å), a NiFe alloy (thickness 70Å), and a Co layer (thickness 10Å), Cu.
Nonmagnetic conductive layer 4 (thickness 30Å), Co (thickness 2
5 Å) pinned magnetic layer 3, Pt _54.4 Mn _45.6 (thickness 300 Å) antiferromagnetic layer 2, Ta (thickness 50 Å)
The protective layer 220 is formed in this order.

The bottom spin-valve thin film magnetic element shown by the black square mark shown in FIG. 21 has an underlayer made of Al ₂ O ₃ (thickness 1000 Å) on the Si substrate K, as shown in FIG. Insulating layer 200, underlayer 210 made of Ta (thickness 30 Å), antiferromagnetic layer 2 made of Pt _55.4 Mn _44.6 (thickness 300 Å), fixed magnetic layer 3 made of Co (thickness 25 Å), Cu (thickness) 26Å) non-magnetic conductive layer 4, C
o layer (thickness 10Å), NiFe alloy (thickness 70Å) 2
The free magnetic layer 5 made of layers and the protective layer 220 made of Ta (thickness 50Å) are formed in this order.

That is, in the top-type spin-valve thin-film magnetic element indicated by ♦, the antiferromagnetic layer 2 is arranged above the pinned magnetic layer 3 and the Si substrate K and the antiferromagnetic layer 2 are provided between the antiferromagnetic layer 2 and the pinned magnetic layer 3. The free magnetic layer 5, the non-magnetic conductive layer 4, and the pinned magnetic layer 3 are sandwiched and formed. That is, in the bottom-type spin-valve thin-film magnetic element indicated by the black square mark, the antiferromagnetic layer 2 is the fixed magnetic layer 3
The pinned magnetic layer 3, the nonmagnetic conductive layer 4, and the free magnetic layer 5 are not formed between the Si substrate K and the antiferromagnetic layer 2 on the lower side.

As shown in FIG. 21, the exchange anisotropy field of the antiferromagnetic layer (Pt _55.4 Mn _44.6 ) indicated by ▪ is 220 ° C.
Begins to rise after passing 700 ° C and rises above 700 (O
e) becomes constant and becomes constant. In addition, the exchange anisotropic magnetic field of the antiferromagnetic layer (Pt _54.4 Mn _45.6 ) indicated by ♦ is 240
Rises above ℃, 600 (Oe) above 260 ℃
Will be constant beyond. In this way, the antiferromagnetic layer (marked with ■) arranged close to the substrate has a relatively low heat treatment temperature as compared with the antiferromagnetic layer arranged with distance from the substrate (marked ◆). It can be seen that a high exchange anisotropic magnetic field can be obtained.

The method of manufacturing the spin-valve type thin film magnetic element 1 of the present invention utilizes the above-mentioned properties of the antiferromagnetic layer. That is, the spin valve thin film magnetic element 1 of the present invention
Is a bottom-type spin-valve thin-film magnetic element 1 in which the antiferromagnetic layer 2 and the substrate K are close in distance (or the antiferromagnetic layer 2 is arranged under the fixed magnetic layer 3), and A bias layer 6 made of a material similar to the alloy used for the magnetic layer 2 is arranged farther from the substrate K than the antiferromagnetic layer 2.

Therefore, for example, when the first laminated body a1 is heat-treated at the first heat treatment temperature (220 to 270 ° C.) while applying the first magnetic field, the exchange anisotropic magnetic field is generated in the antiferromagnetic layer 2. Occurs, and the magnetization direction of the pinned magnetic layer 3 is pinned. The exchange anisotropic magnetic field of the antiferromagnetic layer 2 is 600
Oe (48000 A / m) or more. Next, while applying a second magnetic field in a direction orthogonal to the first magnetic field, the second laminated body a2 is heated at the second heat treatment temperature (250 to 270 ° C.).
Is heat-treated, the magnetization direction of the free magnetic layer 5 is made to intersect with the first magnetic field. In addition, the bias layer 6
The exchange anisotropic magnetic field of 600 Oe (48000 A /
m) or more.

At this time, if the second magnetic field is made smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 2 generated by the previous heat treatment, the second magnetic field is applied to the antiferromagnetic layer 2. However, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is not deteriorated, and the magnetization direction of the pinned magnetic layer 3 can be kept fixed. As a result, the magnetization direction of the pinned magnetic layer 3 and the magnetization direction of the free magnetic layer 5 can be made to intersect each other.

The first heat treatment temperature is 220 ° C. to 270 ° C.
It is preferable to set it as the range. First heat treatment temperature is 22
If it is less than 0 ° C, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is 2
Since the magnetization of the pinned magnetic layer 3 does not become higher than 00 (Oe) and the magnetization direction of the pinned magnetic layer 3 is magnetized in the same direction as the magnetization direction of the free magnetic layer 5 by the second heat treatment, it is preferable. Absent. On the other hand, the first heat treatment temperature is 27
If the temperature exceeds 0 ° C, the interface between the layers, especially the non-magnetic conductive layer 4
Which causes deterioration of the magnetoresistive effect due to thermal diffusion of atoms at the interface between the Cu layer and the free magnetic layer 5 or the Cu layer and the pinned magnetic layer 3, which is not preferable. Further, when the first heat treatment temperature is in the range of 230 ° C. to 270 ° C., the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is 400 Oe (32000 A).
/ M) or more, and the magnetization of the pinned magnetic layer 3 can be increased, which is more preferable.

The second heat treatment temperature is 250 ° C. to 270 ° C.
It is preferable to set it as the range. Second heat treatment temperature is 25
When the temperature is less than 0 ° C., the exchange anisotropic magnetic field of the bias layer 6 becomes 4
It is not preferable because the magnetic field cannot be made to be more than 00 Oe (32000 A / m) and the longitudinal bias magnetic field applied to the free magnetic layer 5 cannot be increased. On the other hand, even if the second heat treatment temperature exceeds 270 ° C., the exchange anisotropic magnetic field of the bias layer 6 becomes constant and no longer increases,
This is not preferable because it causes deterioration of the magnetoresistive effect due to atomic heat diffusion at the layer interface.

The first magnetic field is 10 Oe (800 A).
/ M) or more. The first magnetic field is 1
When it is less than 0 Oe (800 A / m), the antiferromagnetic layer 2
Is not preferable because a sufficient exchange anisotropic magnetic field can not be obtained. The second magnetic field is a magnetic field smaller than the exchange coupling magnetic field of the antiferromagnetic layer 2 generated by the first heat treatment, and is 10 to 600 Oe (800 to 48000 A / m).
It is preferably within the range of about. More preferably 2
It is about 00 Oe (1600 A / m). If the second magnetic field is less than 10 Oe (800 A / m), the exchange anisotropic magnetic field of the bias layer 6 cannot be sufficiently obtained, which is not preferable. On the other hand, the second magnetic field is 600 Oe (800-48
000 A / m) is not preferable because the exchange coupling magnetic field of the antiferromagnetic layer generated by the first heat treatment may be deteriorated.

Next, the heat treatment temperature is 245 ° C. or 270.
The relationship between the composition of the antiferromagnetic layer and the exchange anisotropic magnetic field at the temperature of ° C will be described in detail with reference to FIG.
The symbol Δ in the figure indicates a top-type single spin-valve thin film magnetic element in which the antiferromagnetic layer is arranged at a position farther from the substrate than the free magnetic layer (or the antiferromagnetic layer is arranged on the fixed magnetic layer). It shows the relationship between the composition of the antiferromagnetic layer and the exchange anisotropic magnetic field, and the mark Δ in the figure shows that it was heat-treated at 270 ° C. The circles and circles in the figure indicate the bottom type single spin-valve thin film magnetic element in which an antiferromagnetic layer is arranged between the substrate and the free magnetic layer (or an antiferromagnetic layer is arranged under the pinned magnetic layer). The relationship between the composition of the antiferromagnetic layer and the exchange anisotropic magnetic field is shown. The mark ◯ in the figure is 270 ° C. and the mark  in the figure is heat treated at 245 ° C.

Specifically, as shown in FIG. 24, the top type spin-valve type thin film magnetic element indicated by the triangle mark is an underlayer insulating layer made of Al ₂ O ₃ (thickness 1000 Å) on the Si substrate K, as shown in FIG. Underlayer 21 made of 200, Ta (thickness 50Å)
0, NiFe alloy (thickness 70Å), Co (thickness 10Å)
2 free magnetic layers 5 made of Cu, non-magnetic conductive layer 4 made of Cu (thickness 30 Å), pinned magnetic layer 3 made of Co (thickness 25 Å), and Pt _m M n _t (thickness 300 Å) The magnetic layer 2 is composed of a protective layer 220 made of Ta (thickness 50Å).

On the other hand, the bottom type spin-valve type thin film magnetic element indicated by the circles and the circles is, as shown in FIG.
A base insulating layer 200 made of Al ₂ O ₃ (thickness 1000 Å) and a base layer 21 made of Ta (thickness 30 Å) on the substrate K.
0, Pt _m Mn _100-m (thickness 300 Å) antiferromagnetic layer 2, Co (thickness 25 Å) fixed magnetic layer 3, Cu
Nonmagnetic conductive layer 4 made of (thickness 26Å), Co (thickness 1
0 Å), a NiFe alloy (thickness 70 Å) two free magnetic layers 5, Ta (thickness 50 Å) protective layer 22
It has a structure of zero.

In the method of manufacturing the spin-valve thin-film magnetic element 1 of the present invention, the properties of the antiferromagnetic layer of the bottom spin-valve thin-film magnetic element and the top spin-valve thin-film magnetic element shown in FIG. 22 are utilized. There is. That is, in the spin valve thin film magnetic element 1 of the present invention, which is a bottom type spin valve thin film magnetic element, the composition range of the alloy used for the antiferromagnetic layer 2 is the bottom type spin valve thin film magnetic element shown in FIG. The same as the antiferromagnetic layer of the element is preferable,
The composition range of the alloy used for the bias layer 6 is shown in FIG.
The antiferromagnetic layer of the top spin valve thin film magnetic element shown in FIG.

Further, as is clear from FIG. 22, the antiferromagnetic layer of the bottom type spin-valve thin film magnetic element, here the antiferromagnetic layer 2 is X _m Mn _100-m (where X is Pt, P
When the alloy is composed of at least one element of d, Ir, Rh, Ru, and Os), the composition ratio m is shown.
Is preferably 48 atom% ≦ m ≦ 60 atom%. When m is less than 48 atom% or more than 60 atom%,
Even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed, X _m M
The n _100-m crystal lattice is less likely to be ordered into an L10 type regular lattice, and antiferromagnetic properties are not exhibited. That is, the unidirectional exchange coupling magnetic field (exchange anisotropic magnetic field) is not exhibited, which is not preferable.

A more preferable range of the composition ratio m is 4
8 atomic% ≦ m ≦ 58 atomic%. If it is less than 48 atomic% or more than 58 atomic%, the crystal lattice of X _m Mn _100-m will be L1 even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed.
It becomes difficult to order into a 0-type ordered lattice, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. A more preferable range of m is 4
9.8 atom% ≤ m ≤ 58 atom% and the heat treatment temperature is 27
After the second heat treatment at 0 ° C., 400 Oe (320
An exchange anisotropic magnetic field of 00 A / m) or more is obtained.

Further, the antiferromagnetic layer of the bottom type spin valve thin film magnetic element, that is, the antiferromagnetic layer 2 is formed of Pt _m Mn.
_100-mn D _n (where D is Pd, Ir, Rh, Ru, I
At least one element or two or more elements out of r and Os), m and n showing a composition ratio are 48 atomic% ≦
It is preferable that m + n ≦ 60 atomic%, 0.2 atomic% ≦ n ≦ 40 atomic%. When the composition ratio m + n is less than 48 atom% or more than 60 atom%, the second heat treatment temperature of 270 ° C.
Even if the heat treatment is performed, the crystal lattice of Pt _m Mn _100-mn D _n becomes difficult to be ordered into the L10 type ordered lattice, and the antiferromagnetic property is not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, the composition ratio n is 0.
If it is less than 2 atomic%, the effect of promoting the ordering of the crystal lattice of the antiferromagnetic layer 2, that is, the effect of increasing the exchange anisotropic magnetic field becomes poor, which is not preferable, and the composition ratio n is 40 atomic%. On the contrary, if it exceeds, the exchange anisotropic magnetic field decreases, which is not preferable.

A more preferable range of the composition ratio m + n is 48 atom% ≦ m + n ≦ 58 atom%. Composition ratio m
When + n is less than 48 atomic% or more than 58 atomic%, Pt _m M is obtained even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed.
The crystal lattice of n _100-mn D _n becomes difficult to be ordered into an L10 type regular lattice, and antiferromagnetic properties are not exhibited. That is,
It is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, a more preferable range of the composition ratio m + n is 49.
8 atomic% ≦ m + n ≦ 58 atomic%, 0.2% ≦ n ≦ 40, and an exchange anisotropic magnetic field of 400 Oe (32000 A / m) or more can be obtained.

Further, the antiferromagnetic layer of the bottom type spin valve thin film magnetic element, that is, the antiferromagnetic layer 2 is formed of Pt _q Mn.
_100-qj L _j (where L is Au, Ag, Cr, Ni, N
at least one of e, Ar, Xe, and Kr or 2
Q and j, which represent the composition ratio, are 4
8 atom% ≦ q + j ≦ 60 atom%, 0.2 atom% ≦ j ≦ 1
It is preferably 0 atomic%. When the composition ratio q + j is less than 48 atom% or more than 60 atom%, the heat treatment temperature 27
Even if the second heat treatment at 0 ° C. is performed, Pt _q Mn _100-qj L _j
It becomes difficult to regularize the crystal lattice of L to the L10 type regular lattice, and the antiferromagnetic property is not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, if the composition ratio j is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element L is not sufficiently exhibited, which is not preferable. It is not preferable because the sex exchange anisotropic magnetic field is lowered.

A more preferable range of q + j showing the composition ratio is 48 atom% ≦ q + j ≦ 58 atom%. When the composition ratio q + j is less than 48 atomic% or exceeds 58 atomic%, even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed, P
t the crystal lattice of _q Mn _100-qj L _j is less likely to ordered to L10-type ordered lattice, not exhibit antiferromagnetic properties.
That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, the more preferable range of q + j showing the composition ratio is 49.8 atom% ≦ q + j ≦ 58 atom%, 0.2 atom%
≦ j ≦ 10 atomic% and 400 Oe (32000A
/ M) or more of the exchange anisotropic magnetic field is obtained.

As is clear from FIG. 22, the antiferromagnetic layer of the top-type spin-valve thin-film magnetic element, here, the bias layer 6 is formed by X _m Mn _100-m (where X is Pt, P
When the alloy is composed of at least one element selected from d, Ir, Rh, Ru, and Os), the composition ratio m is 5
It is preferable that 2 atomic% ≦ m ≦ 60 atomic%. When the composition ratio m is less than 52 atom% or more than 60 atom%, X is not affected even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed.
The crystal lattice of _m Mn _100-m becomes difficult to be ordered into an L10 type regular lattice, and the antiferromagnetic property is not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field.
Moreover, the more preferable range of the composition ratio m is 52.8 atomic%.
≦ m ≦ 59.2 atomic% and 200 Oe (16000
An exchange anisotropic magnetic field of A / m) or more, that is, a bias magnetic field is obtained.

Further, the antiferromagnetic layer of the top spin valve thin film magnetic element, that is, the bias layer 6 is formed of Pt _m Mn.
_100-mn D _n (where D is Pd, Rh, Ru, Ir, O
When at least one element or two or more elements of s), m and n showing the composition ratio are 52 atom% ≦ m + n ≦
It is preferable that 60 atomic% and 0.2 atomic% ≦ n ≦ 40 atomic%.

The composition ratio m + n is less than 52 atomic% or 60
If the atomic percentage is exceeded, even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed, the crystal lattice of Pt _m Mn _100-mn D _n becomes L10.
It becomes difficult to form a regular lattice of the type, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, the composition ratio n is 0.2 atomic%
If it is less than the above range, the effect of promoting the ordering of the crystal lattice of the antiferromagnetic layer 2, that is, the effect of increasing the exchange anisotropic magnetic field becomes poor, which is not preferable, and if the composition ratio n exceeds 40 atom%, Conversely, the exchange anisotropic magnetic field decreases, which is not preferable. Furthermore, a more preferable range of the composition ratio m + n is 52.
8 atom% ≦ m + n ≦ 59.2 atom%, 0.2 atom% ≦ n ≦
40 atomic% and 200 Oe (16000 A / m)
The above exchange anisotropic magnetic field, that is, the bias magnetic field is obtained.

The antiferromagnetic layer of the top spin valve thin film magnetic element, that is, the bias layer 6 is formed of Pt _q Mn.
_100-qj L _j (where L is Au, Ag, Cr, Ni, N
at least one of e, Ar, Xe, and Kr or 2
Q and j, which represent the composition ratio, are 5
2 atom% ≦ q + j ≦ 60 atom%, 0.2 atom% ≦ j ≦ 1
It is preferably 0 atomic%. When the composition ratio q + j is less than 52 atomic% or exceeds 60 atomic%, the heat treatment temperature 27
Even if the second heat treatment at 0 ° C. is performed, Pt _q Mn _100-qj L _j
It becomes difficult to regularize the crystal lattice of L to the L10 type regular lattice, and the antiferromagnetic property is not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, if j is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element L is not sufficiently exhibited, which is not preferable, and if j exceeds 10 atomic%, unidirectional exchange is performed. This is not preferable because the coupling magnetic field is reduced.

Further, the more preferable range of the composition ratio m + n is 52.8 atomic% ≦ m + n ≦ 59.2 atomic%, 0.2 atomic% ≦ n ≦ 40 atomic%, and the exchange difference of 200 (Oe) or more. An anisotropic magnetic field, that is, a bias magnetic field is obtained.

Further, as is apparent from FIG. 22, the antiferromagnetic layer of the bottom type spin-valve type thin film magnetic element, here the antiferromagnetic layer 2 and the antiferromagnetic layer of the top type spin-valve type thin film magnetic element here. Then, the bias layer 6 is X _mm
n _100-m (where X is Pt, Pd, Ir, Rh, R
In the case of an alloy composed of at least one element of u and Os), m representing the composition ratio of the antiferromagnetic layer 2 and the bias layer 6 is 52 atom% ≦ m ≦ 58 atom%.
Is preferred.

When the composition ratio m is less than 52 atomic%, the crystal lattice of X _m Mn _100-m forming the bias layer 6 is L10 type even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed. It becomes difficult to regularize into a lattice and no antiferromagnetic property is exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. When the composition ratio m exceeds 58 atomic%, the crystal lattice of X _m Mn _100-m forming the antiferromagnetic layer 2 is an L10 type regular lattice even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed. It becomes difficult to order, and antiferromagnetic properties are not exhibited. That is, the unidirectional exchange coupling magnetic field is not exhibited, and when the second heat treatment at the heat treatment temperature of 270 ° C. is performed, the magnetization direction of the pinned magnetic layer 3 is magnetized to be the same as the magnetization direction of the bias layer 6, or the pinned magnetic layer is magnetized. The magnetization direction of 3 is no longer orthogonal to the magnetization direction of the bias layer 6, and as a result,
This is not preferable because the symmetry of the reproduction output waveform cannot be obtained.

When the antiferromagnetic layer 2 and the bias layer 6 are made of an alloy of X _m Mn _{100-m, m} showing the composition ratio of the antiferromagnetic layer 2 and the bias layer 6 is 52.
More preferably, atomic% ≤ m ≤ 56.3 atomic%.

When the composition ratio m is less than 52 atomic%, the bias layer 6 is subjected to the second heat treatment at the heat treatment temperature of 270 ° C.
The crystal lattice of XmMn100-m constituting the above is less likely to be ordered into an L10 type ordered lattice, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, when the composition ratio m exceeds 56.3 atom%, the exchange anisotropic magnetic field by the bias layer 6 becomes larger than the exchange anisotropic magnetic field by the antiferromagnetic layer 2, and the second heat treatment temperature of 270 ° C. When the heat treatment is performed, an external magnetic field larger than the exchange anisotropic magnetic field generated by the antiferromagnetic layer 2 is applied to the bias layer 6, and the heat treatment temperature is 270 ° C.
During the second heat treatment of, the pinned magnetic layer 3 becomes the free magnetic layer 5.
Is not preferable because it is magnetized in the same direction as the magnetization of No. 2 or it becomes difficult to align the magnetization direction of the free magnetic layer 5 and the magnetization direction of the pinned magnetic layer 3 in the orthogonal direction during the second heat treatment.

Therefore, the antiferromagnetic layer 2 and the bias layer 6
If the above composition ratio is within the range of 52 atomic% ≤ m ≤ 56.3 atomic%, an exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated during the first heat treatment, and after the second heat treatment is performed. Antiferromagnetic layer 2
Since the exchange anisotropic magnetic field of is larger than the exchange coupling magnetic field of the bias layer 6, the magnetization direction of the pinned magnetic layer 3 is fixed without changing with respect to the application of the signal magnetic field from the magnetic recording medium,
The magnetization direction of the free magnetic layer 5 can change smoothly, which is preferable.

Further, the antiferromagnetic layer 2 and the bias layer 6 are Pt _m Mn _100-mn D _n (where D is Pd, Ir, R).
h, Ru, Os, at least one kind or two or more kinds of elements), m and n showing a composition ratio are 52 atom% ≦ m + n ≦ 58 atom% and 0.2 atom% ≦ n ≦ 40. It is preferably atomic%.

When the composition ratio m + n is less than 52 atomic%,
Even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed, the crystal lattice of Pt _m Mn _100-mn D _n forming the bias layer 6 is less likely to be ordered into the L10 type ordered lattice, and the antiferromagnetic property is improved. No longer show. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. When m + n exceeds 58 atomic%, Pt _m Mn forming the antiferromagnetic layer 2 is formed even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed.
The crystal lattice of _100-mn D _n is less likely to be regularized into an L10 type regular lattice, and antiferromagnetic properties are not exhibited. That is, the unidirectional exchange coupling magnetic field is not exhibited, and the heat treatment temperature 270
When the second heat treatment at 0 ° C. is performed, the magnetization direction of the pinned magnetic layer 3 becomes the same as the magnetization direction of the bias layer 6, or the magnetization direction of the pinned magnetic layer 3 is no longer orthogonal to the magnetization direction of the bias layer 6. As a result, the symmetry of the reproduced output waveform cannot be obtained, which is not preferable.

If the composition ratio n is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element D is not sufficiently exhibited, which is not preferable, and n is 40 atomic%.
If it exceeds, the unidirectional exchange coupling magnetic field is reduced, which is not preferable.

When the antiferromagnetic layer 2 and the bias layer 6 are alloys made of Pt _m Mn _100-mn D _n ,
The composition ratio m and n are 52 atomic% ≤ m + n ≤ 56.3
Atom%, 0.2 atom% ≤ n ≤ 40 atom% is more preferable.

When the composition ratio m + n is less than 52 atomic%,
Even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed, the crystal lattice of Pt _m Mn _100-mn D _n forming the bias layer 6 is less likely to be ordered into the L10 type ordered lattice, and the antiferromagnetic property is improved. No longer show. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. When the composition ratio m + n exceeds 56.3 atom%, the exchange anisotropic magnetic field by the bias layer 6 becomes larger than the exchange anisotropic magnetic field by the antiferromagnetic layer 2 and the second heat treatment temperature of 270 ° C. When the heat treatment is performed, an external magnetic field larger than the exchange anisotropic magnetic field generated by the antiferromagnetic layer 2 is applied to the bias layer 6,
During the second heat treatment at the heat treatment temperature of 270 ° C., the pinned magnetic layer 3 is magnetized in the same direction as the magnetization of the free magnetic layer 5, or during the second heat treatment, the magnetization direction of the free magnetic layer 5 is fixed. It is difficult to align the magnetization direction of the magnetic layer 3 in the direction perpendicular to the magnetization direction, which is not preferable.

If the composition ratio n is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element D is not sufficiently exhibited, which is not preferable, and n is 40 atomic%.
If it exceeds, the unidirectional exchange coupling magnetic field is reduced, which is not preferable.

Therefore, the antiferromagnetic layer 2 and the bias layer 6
If the above composition ratio is 52 atomic% ≤ m + n ≤ 56.3 atomic% and 0.2 atomic% ≤ n ≤ 40 atomic%, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 during the first heat treatment. Occurs, and after the second heat treatment, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 becomes larger than the exchange coupling magnetic field of the bias layer 6,
The magnetization direction of the pinned magnetic layer 3 is fixed without changing in response to the application of a signal magnetic field from the magnetic recording medium, and the magnetization direction of the free magnetic layer 5 can smoothly change, which is preferable.

Further, the antiferromagnetic layer 2 and the bias layer 6
Is Pt _q Mn _100-qj L _j (where L is Au, Ag, C
r, Ni, Ne, Ar, Xe, Kr) and an alloy having a composition of at least one element or two or more elements, q and j indicating the composition ratio are 52 atomic% ≤ q + j ≤ 5
It is preferable that 8 atomic% and 0.2 atomic% ≦ j ≦ 10 atomic%.

When the composition ratio q + j is less than 52 atomic%,
Even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed, the crystal lattice of Pt _q Mn _100-qj L _j forming the bias layer 6 is less likely to be ordered into the L10 type ordered lattice, and the antiferromagnetic property is improved. No longer show. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. When the composition ratio q + j exceeds 58 atomic%, Pt _q M forming the antiferromagnetic layer 2 is formed even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed.
The crystal lattice of n _100-qj L _j is less likely to be regularized into an L10 type regular lattice, and antiferromagnetic properties are not exhibited. That is,
The unidirectional exchange coupling magnetic field is no longer exhibited, and the heat treatment temperature 27
When the second heat treatment at 0 ° C. is performed, the magnetization direction of the pinned magnetic layer 3 is made the same as the magnetization direction of the bias layer 6, or the magnetization direction of the pinned magnetic layer 3 is orthogonal to the magnetization direction of the bias layer 6. This is not preferable because the symmetry of the reproduction output waveform cannot be obtained as a result.

If the composition ratio j is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element L is not sufficiently exhibited, which is not preferable, and j is 10 atomic%.
If it exceeds, the unidirectional exchange coupling magnetic field is reduced, which is not preferable.

When the antiferromagnetic layer 2 and the bias layer 6 are alloys made of Pt _q Mn _100-qj L _j ,
Q and j indicating the composition ratio are 52 atomic% ≦ q + j ≦ 56.3
It is more preferable that atomic% and 0.2 atomic% ≦ j ≦ 10 atomic%.

When the composition ratio q + j is less than 52 atomic%,
Even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed, the crystal lattice of Pt _q Mn _100-qj L _j forming the bias layer 6 is less likely to be ordered into the L10 type ordered lattice, and the antiferromagnetic property is improved. No longer show. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, when the composition ratio q + j exceeds 56.3 atom%, the exchange anisotropic magnetic field by the bias layer 6 becomes larger than the exchange anisotropic magnetic field by the antiferromagnetic layer 2, and the second heat treatment temperature of 270 ° C. When the heat treatment is performed, an external magnetic field larger than the exchange anisotropic magnetic field generated by the antiferromagnetic layer 2 is applied to the bias layer 6,
During the second heat treatment at the heat treatment temperature of 270 ° C., the pinned magnetic layer 3 is magnetized in the same direction as the magnetization of the free magnetic layer 5, or during the second heat treatment, the magnetization direction of the free magnetic layer 5 is fixed. It is difficult to align the magnetization direction of the magnetic layer 3 in the direction perpendicular to the magnetization direction, which is not preferable.

If the composition ratio j is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element L is not sufficiently exhibited, which is not preferable, and j is 10 atomic%.
If it exceeds, the unidirectional exchange coupling magnetic field is reduced, which is not preferable.

Therefore, the antiferromagnetic layer 2 and the bias layer 6
If the above composition ratio is 52 at% ≦ q + j ≦ 56.3 at%, and 0.2 at% ≦ j ≦ 10 at%, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 during the first heat treatment is Occurs, and after the second heat treatment, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 becomes larger than the exchange coupling magnetic field of the bias layer 6,
When the signal magnetic field is applied from the magnetic recording medium, the magnetization direction of the fixed magnetic layer 3 is fixed without being changed, and the free magnetic layer 5 is fixed.
The magnetization direction of is preferable because it can change smoothly.

Further, the composition of the antiferromagnetic layer of the bottom type spin valve thin film magnetic element, here the antiferromagnetic layer 2,
Antiferromagnetic layer of top-type spin-valve thin-film magnetic element Here, the composition of the bias layer 6 is made different, and for example, the Mn concentration of the antiferromagnetic layer 2 is made higher than the Mn concentration of the bias layer 6. The difference between the exchange coupling magnetic fields of the two after the heat treatment can be made more remarkable, and the magnetizations of the free magnetic layer 5 and the pinned magnetic layer 3 can be more surely brought into the orthogonal state after the second heat treatment. Further, the difference in the exchange anisotropic magnetic fields of both the antiferromagnetic layer 2 and the bias layer 6 having different Mn concentrations after the second heat treatment can be made more remarkable, and the signal magnetic field from the magnetic recording medium can be increased. The magnetization direction of the pinned magnetic layer 3 does not change and the magnetization direction of the free magnetic layer 5 can be smoothly changed in response to the application of.

That is, the bias layer 6 is formed of X _m Mn _100-m (X
Is at least one element selected from Pt, Pd, Ir, Rh, Ru, and Os, and m representing the composition ratio is 52 atomic% ≦
m ≦ 60 atomic%), and the antiferromagnetic layer 2 is
X _m Mn _100-m (X is Pt, Pd, Ir, Rh, Ru,
It is more preferable to use an alloy in which at least one element of Os and m indicating the composition ratio are 48 atom% ≦ m ≦ 58 atom%).

When the content m of the bias layer 6 is less than 52 atom% or more than 60 atom%, as shown in FIG. 22, even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed,
The crystal lattice of X _m Mn _100-m forming the bias layer 6 is L1.
It becomes difficult to order into a 0-type ordered lattice, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, when m representing the composition of the antiferromagnetic layer 2 is less than 48 atomic% or more than 58 atomic%, X _m Mn forming the antiferromagnetic layer 2 even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed. _{The 100-m} crystal lattice is less likely to be regularized into an L10 type regular lattice, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field.

Therefore, the first heat treatment temperature of 245 ° C.
After the heat treatment is performed, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated, and during the second heat treatment at the second heat treatment temperature of 270 ° C. Is applied to the antiferromagnetic layer 2 so that the exchange anisotropic magnetic field of the antiferromagnetic layer 2 becomes larger than that of the bias layer 6 after the second heat treatment. The composition ratio may be selected from the range of the composition ratio of 2 (48 atom% ≤ m ≤ 58 atom%) and the composition ratio of the bias layer 6 (52 atom% ≤ m ≤ 60 atom%). .

The antiferromagnetic layer 2 is formed by selecting composition ratios satisfying such conditions and making the composition ranges different.
And the bias layer 6 having the same composition as the second
It becomes possible to make a combination in which the difference between the exchange coupling magnetic field of the antiferromagnetic layer 2 and the exchange anisotropic magnetic field of the bias layer 6 at the time of the heat treatment is marked, and the degree of freedom in design is improved. Also, the first
By generating an exchange anisotropic magnetic field of the antiferromagnetic layer 2 during the heat treatment of, and applying an external magnetic field smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 2 during the second heat treatment. , The magnetization directions of the free magnetic layer 5 and the pinned magnetic layer 3 are fixed while the magnetization direction of the pinned magnetic layer 3 is firmly fixed without deteriorating the exchange anisotropic magnetic field of the antiferromagnetic layer 2 or changing the magnetization direction. Can be crossed.

Furthermore, after the second heat treatment, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 can be made larger than that of the bias layer 6, and the signal magnetic field from the magnetic recording medium can be applied. On the other hand, the magnetization direction of the fixed magnetic layer 3 is fixed without changing, and the magnetization direction of the free magnetic layer 5 can be changed smoothly.

Another preferable combination of the antiferromagnetic layer 2 and the bias layer 6 is that the bias layer 6 is Pt _m Mn _100-mn D.
_n (D is at least one element selected from the group consisting of Pd, Ir, Rh, Ru, Os, and two or more elements;
, 52 atomic% ≤ m + n ≤ 60 atomic%, 0.2 atomic% ≤
n ≦ 40 atomic%), and the antiferromagnetic layer 2 is
Pt _m Mn _100-mn D _n (where D is Pd, Ir, R
At least one element selected from h, Ru, and Os, or two or more elements, and m and n indicating the composition ratio are 48 atom% ≦ m + n.
≦ 58 atomic%, 0.2 atomic% ≦ n ≦ 40 atomic%) is preferable.

When m + n indicating the composition of the bias layer 6 is less than 52 atomic% or more than 60 atomic%, the heat treatment temperature is 2
Even if the second heat treatment at 70 ° C. is performed, the crystal lattice of Pt _m Mn _100-mn D _n forming the bias layer 6 becomes difficult to be ordered into the L10 type ordered lattice, and the antiferromagnetic property is not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. If n, which represents the composition of the bias layer 6, is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element D is not sufficiently exhibited, which is not preferable, and n is 40 atomic%. If it exceeds, the unidirectional exchange coupling magnetic field will decrease, which is not preferable.

When m + n, which represents the composition of the antiferromagnetic layer 2, is less than 48 atomic% or more than 58 atomic%, the antiferromagnetic layer 2 is subjected to the first heat treatment at the heat treatment temperature of 245 ° C.
The crystal lattice of Pt _m Mn _100-mn D _n that composes is difficult to be ordered into an L10 type ordered lattice, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. If n, which indicates the composition of the second antiferromagnetic layer, is less than 0.2 atomic%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element D is not sufficiently exhibited, which is not preferable, and n is 40 or less. Exceeding atomic% is not preferable because the unidirectional exchange coupling magnetic field decreases.

Therefore, the first heat treatment temperature of 245 ° C.
After the heat treatment of 1., the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated, and during the second heat treatment at the second heat treatment temperature of 270.degree. Is applied so that the exchange anisotropic magnetic field of the antiferromagnetic layer 2 becomes larger than the exchange anisotropic magnetic field of the bias layer 6 after the second heat treatment. 2 may be selected from the range of the composition ratio of 2 (48 atom% ≦ m + n ≦ 58 atom%) and the composition ratio of the bias layer 6 (52 atom% ≦ m + n ≦ 60 atom%). .

The antiferromagnetic layer 2 is formed by selecting the composition ratios satisfying such conditions and making the composition ranges different.
And the bias layer 6 having the same composition as the second
A combination that can make the difference between the exchange coupling magnetic field of each antiferromagnetic layer 2 and the exchange anisotropic magnetic field of the bias layer 6 at the time of the heat treatment of 2 becomes possible, and the degree of freedom in design is improved. Further, an exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated during the first heat treatment, and an external magnetic field smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated during the second heat treatment. By applying the magnetic field, the free magnetic layer 5 and the pinned magnetic layer 3 are firmly fixed in the magnetization direction of the pinned magnetic layer 3 without deteriorating the exchange anisotropic magnetic field of the antiferromagnetic layer 2 or changing the magnetization direction. The magnetization directions can be crossed.

Furthermore, after the second heat treatment, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 can be made larger than the exchange anisotropic magnetic field of the bias layer 6, and when the signal magnetic field from the magnetic recording medium is applied, The magnetization direction of the fixed magnetic layer 3 is fixed without changing, and the magnetization direction of the free magnetic layer 5 can be changed smoothly.

Another preferable combination of the antiferromagnetic layer 2 and the bias layer 6 is that the bias layer 6 is Pt _q Mn _100-qj L _j.
(However, L is Au, Ag, Cr, Ni, Ne, Ar,
At least one element or two or more elements of Xe and Kr, q and j showing the composition ratio are 52 atomic% ≤ q + j ≤ 60
Atomic%, 0.2 at% ≦ j ≦ 10 at%), and the antiferromagnetic layer 2 is made of Pt _q Mn _100-qj L _j (however,
L is Au, Ag, Cr, Ni, Ne, Ar, Xe, K
at least one element or two or more elements out of r, q and j indicating the composition ratio are 48 atomic% ≦ q + j ≦ 58 atomic%,
The alloy is preferably made of 0.2 atomic% ≤ j ≤ 10 atomic%.

Q + j showing the composition of the bias layer 6 is 52.
If it is less than atomic% or more than 60 atomic%, the crystal lattice of Pt _q Mn _100-qj L _j forming the bias layer 6 becomes an L10 type regular lattice even if the second heat treatment at the heat treatment temperature of 270 ° C. is performed. It becomes difficult to be ordered and does not exhibit antiferromagnetic properties. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. In addition, j showing the composition of the bias layer 6
However, if it is less than 0.2 atom%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element L is not sufficiently exhibited, which is not preferable, and if the composition ratio j exceeds 10 atom%, unidirectional exchange is performed. This is not preferable because the coupling magnetic field is reduced.

Also, q + j showing the composition of the antiferromagnetic layer 2
However, if less than 48 atomic% or more than 58 atomic%, the crystal lattice of Pt _q Mn _100-qj L _j forming the antiferromagnetic layer 2 is L1 even if the first heat treatment at the heat treatment temperature of 245 ° C. is performed.
It becomes difficult to order into a 0-type ordered lattice, and antiferromagnetic properties are not exhibited. That is, it is not preferable because it does not show a unidirectional exchange coupling magnetic field. Further, if j representing the composition of the antiferromagnetic layer 2 is less than 0.2 atom%, the effect of improving the unidirectional exchange coupling magnetic field by the addition of the element L is not sufficiently exhibited, which is not preferable, and j is 10 or less. Exceeding atomic% is not preferable because the unidirectional exchange coupling magnetic field decreases.

Therefore, the first heat treatment temperature of 245 ° C.
After the heat treatment of 1., the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated, and during the second heat treatment at the second heat treatment temperature of 270.degree. Is applied so that the exchange anisotropic magnetic field of the antiferromagnetic layer 2 becomes larger than the exchange anisotropic magnetic field of the bias layer 6 after the second heat treatment. The composition ratio may be selected from the range of the composition ratio of 2 (48 atom% ≦ q + j ≦ 58 atom%) and the composition ratio of the bias layer 6 (52 atom% ≦ q + j ≦ 60 atom%). .

The antiferromagnetic layer 2 is formed by selecting the composition ratios that satisfy such conditions and making the composition ranges different.
When compared with the case where the bias layer 6 and the bias layer 6 are formed with the same composition,
It becomes possible to make a combination in which the difference between the exchange coupling magnetic field of the antiferromagnetic layer 2 and the exchange anisotropic magnetic field of the bias layer 6 becomes remarkable during the heat treatment and the second heat treatment, and the degree of freedom in design is improved. . Further, an exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated during the first heat treatment, and an external magnetic field smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 2 is generated during the second heat treatment. By applying the magnetic field, the free magnetic layer 5 and the pinned magnetic layer 3 are firmly fixed in the magnetization direction of the pinned magnetic layer 3 without deteriorating the exchange anisotropic magnetic field of the antiferromagnetic layer 2 or changing the magnetization direction. The magnetization directions can be crossed.

Furthermore, after the second heat treatment, the exchange anisotropic magnetic field of the antiferromagnetic layer 2 can be made larger than the exchange anisotropic magnetic field of the bias layer 6 and fixed with respect to the application of the signal magnetic field from the magnetic recording medium. The magnetization direction of the magnetic layer 3 is fixed without changing, and the magnetization direction of the free magnetic layer 5 can be changed smoothly.

Such a spin valve thin film magnetic element 1
Then, the antiferromagnetic layer 2 and the bias layer 6 are Pt, P
d, Rh, Ru, Ir, Os, Au, Ag, Cr, N
Since it is made of an alloy containing at least one element selected from i, Ne, Ar, Xe, and Kr and Mn and Mn, the temperature characteristic of the exchange anisotropic magnetic field is good and the heat resistance is excellent. The spin valve thin film magnetic element 1 is obtained.

For example, the blocking temperature of PtMn alloy is about 380 ° C., which is higher than that of FeMn alloy used for the bias layer in the conventional spin valve thin film magnetic element, which is 150 ° C. Therefore, the spin valve type is excellent in durability when provided in a device such as a thin film magnetic head whose temperature in the device is high, and has little fluctuation of the exchange anisotropic magnetic field (exchange coupling magnetic field) due to temperature change. The thin film magnetic element 1 can be used.

Furthermore, by forming the antiferromagnetic layer 2 with the above-mentioned material, the blocking temperature becomes high, and a large exchange anisotropic magnetic field can be generated in the antiferromagnetic layer 2, so that the fixed magnetic The magnetization direction of the layer 3 can be firmly fixed. Among the bias layer 6 and the antiferromagnetic layer 2 of the present invention, the blocking temperature of PtMn alloy is 380.
Is higher than 230 ° C of IrMn alloy,
More preferable.

Such a spin valve thin film magnetic element 1
In the manufacturing method of, the antiferromagnetic layer 2 and the bias layer 6 are
Pt, Pd, Rh, Ru, Ir, Os, Au, Ag, C
An alloy containing at least one element or two or more elements out of r, Ni, Ne, Ar, Xe, and Kr and Mn is used, and by utilizing the properties of the alloy, the fixed magnetic layer is formed by the first heat treatment. Since the magnetization direction of the fixed magnetic layer 3 is fixed and the magnetization direction of the free magnetic layer 5 is aligned in the direction intersecting the magnetization direction of the fixed magnetic layer 3 by the second heat treatment, the magnetization direction of the fixed magnetic layer 3 is not adversely affected. The magnetization direction of the free magnetic layer 5 can be aligned with the direction crossing the magnetization direction of the pinned magnetic layer 3, and the spin valve thin film magnetic element 1 having excellent heat resistance can be obtained.

Further, in the method for manufacturing the spin-valve thin film magnetic element, the soft magnetic layers 7 and 7 are formed on the first laminated body a1, and the bias layers 6 and 7 are formed on the soft magnetic layers 7 and 7. Since it is a method of forming 6, the bias layers 6 and 6 can be formed without breaking the vacuum after forming the soft magnetic layers 7 and 7, and the surface on which the bias layers 6 and 6 are formed can be formed. Since there is no need to perform cleaning by ion milling or reverse sputtering, there is no inconvenience caused by cleaning such as contamination due to redeposits and adverse effects on the generation of exchange anisotropic magnetic field due to disorder of the crystal state of the surface. It can be a manufacturing method. Moreover, since it is not necessary to clean the surface on which the bias layers 6 and 6 are formed before forming the bias layers 6 and 6, it is possible to easily manufacture.

On the other hand, the ferromagnetic coupling at the interface between the free magnetic layer 5 and the soft magnetic layer 7 is less sensitive to contamination than the exchange coupling at the interface with the antiferromagnetic layer. Therefore, even if the soft magnetic layer 7 is formed after being exposed to the atmosphere, the free magnetic layer 5 is sufficiently formed.
Although a vertical bias magnetic field can be secured to the soft magnetic layer 7, cleaning by ion milling, reverse sputtering, or the like may be performed before breaking the soft magnetic layer 7 without breaking the vacuum.

Further, by using the thin-film magnetic head in which the above spin-valve thin-film magnetic element 1 is provided on the slider 151, the durability and heat resistance are excellent, and the reliability that a sufficient exchange anisotropic magnetic field can be obtained. It is possible to obtain a thin film magnetic head having high efficiency.

In the spin valve thin film magnetic element 1 of the first embodiment of the present invention, as described above, the fixed magnetic layer 3 and the free magnetic layer 5 are provided above and below the nonmagnetic conductive layer 4 in the thickness direction, respectively. Although it is provided as a single layer structure, these may be provided as a plurality of structures.

The mechanism showing the giant magnetoresistance change is due to the spin-dependent scattering of conduction electrons generated at the interface between the nonmagnetic conductive layer 4, the pinned magnetic layer 3 and the free magnetic layer 5.
A Co layer can be exemplified as a combination having a large spin-dependent scattering with respect to the nonmagnetic conductive layer 4 made of Cu or the like. Therefore, when the pinned magnetic layer 3 is formed of a material other than Co, the portion of the pinned magnetic layer 3 on the nonmagnetic conductive layer 4 side is formed as shown in FIG.
It is preferable to form the thin Co layer 3a as indicated by the two-dot chain line. Also, when the free magnetic layer 5 is formed of a material other than Co, as in the case of the fixed magnetic layer 3, the portion of the free magnetic layer 5 on the nonmagnetic conductive layer 4 side is indicated by the chain double-dashed line in FIG. It is preferable to form the thin Co layer 5a.

[Second Embodiment] FIG. 7 shows a second embodiment of the present invention.
FIG. 9 is a transverse cross-sectional view schematically showing the spin-valve thin-film magnetic element of the embodiment of the present invention, and FIG. 8 shows the spin-valve thin-film magnetic element shown in FIG. 7 when viewed from the side facing the recording medium. 3 is a cross-sectional view showing the structure of FIG. Also in this spin-valve thin-film magnetic element, like the spin-valve thin-film magnetic element shown in FIG. 1, the spin-valve thin-film magnetic element is provided at the trailing side end of the floating slider provided in the hard disk device.
The recording magnetic field of a hard disk or the like is detected.
The moving direction of the magnetic recording medium such as a hard disk is the Z direction in the figure, and the direction of the leakage magnetic field from the magnetic recording medium is the Y direction.

The spin-valve type thin film magnetic element shown in FIGS. 7 and 8 has an antiferromagnetic layer, a fixed magnetic layer, a nonmagnetic conductive layer,
It is a kind of so-called bottom type single spin valve thin film magnetic element in which a free magnetic layer is formed one by one. Also, the spin-valve thin-film magnetic element of this example, like the spin-valve thin-film magnetic element shown in FIG. 1, changes the magnetization direction of the free magnetic layer by an exchange bias method using a bias layer made of an antiferromagnetic material. It is aligned in a direction intersecting with the magnetization direction of the pinned magnetic layer.

In FIGS. 7 and 8, reference numeral K indicates a substrate. An insulating underlayer 200 of Al2O3 or the like, a lower shield layer 163, a lower gap layer 164, and an antiferromagnetic layer 11 are formed on the substrate K. The fixed magnetic layer 12 is formed. Then, on the first pinned magnetic layer 12,
A nonmagnetic intermediate layer 13 is formed, and a second pinned magnetic layer 14 is formed on the nonmagnetic intermediate layer 13. A nonmagnetic conductive layer 15 is formed on the second pinned magnetic layer 14, and a free magnetic layer 16 is further formed on the nonmagnetic conductive layer 15.

Soft magnetic layers 19 are provided on the free magnetic layer 16 with a space corresponding to the track width Tw. Bias layers 130 and 130 are provided on the soft magnetic layers 19 and 19, and conductive layers 131 and 131 are formed on the bias layers 130 and 130.

In this spin-valve thin-film magnetic element, the antiferromagnetic layer 11 is made of Pt, Pd, Ir, R, as in the spin-valve thin-film magnetic element of the first embodiment.
h, Ru, Ir, Os, Au, Ag, Cr, Ni, N
at least one of e, Ar, Xe, and Kr or 2
It is made of an alloy containing Mn and one or more elements, and is configured to magnetize the first pinned magnetic layer 12 and the second pinned magnetic layer 14 in a fixed direction by heat treatment in a magnetic field.

The first pinned magnetic layer 12 and the second pinned magnetic layer 14 are, for example, Co film, NiFe alloy, Co.
It is formed of a NiFe alloy, a CoNi alloy, a CoFe alloy, or the like. The non-magnetic intermediate layer 13 interposed between the first pinned magnetic layer 12 and the second pinned magnetic layer 14 is R
It is preferable to be formed of an alloy of one or more of u, Rh, Ir, Cr, Re and Cu.

By the way, the first pinned magnetic layer 1 shown in FIG.
The arrows shown on the second and second pinned magnetic layers 14 respectively indicate the magnitude of the magnetic moment and the direction thereof, and the magnitude of the magnetic moment indicates the saturation magnetization (M
s) and the film thickness (t).

First pinned magnetic layer 1 shown in FIGS. 7 and 8.
2 and the second pinned magnetic layer 14 are formed of the same material, and the film thickness tP _{2 of} the second pinned magnetic layer 14 is larger than the film thickness tP _{1 of} the first pinned magnetic layer 12. Therefore, the second pinned magnetic layer 14 has a larger magnetic moment than the first pinned magnetic layer 12. In addition, the first pinned magnetic layer 12 and the second pinned magnetic layer 14
Preferably have different magnetic moments. Therefore, the film thickness tP ₁ of the _first pinned magnetic layer 12 may be formed to be thicker than the film thickness tP _{2 of} the second pinned magnetic layer 14.

The first pinned magnetic layer 12 is shown in FIGS.
, The non-magnetic intermediate layer 13 is magnetized in the Y direction in the drawing, that is, in the direction away from the recording medium (height direction).
The magnetization of the second pinned magnetic layer 14 opposed to each other via is magnetized antiparallel (ferry state) to the magnetization direction of the first pinned magnetic layer 12.

The first pinned magnetic layer 12 is the antiferromagnetic layer 11
The first pinned magnetic layer 12 and the antiferromagnetic layer 11 by being annealed (heat treatment) in a magnetic field.
An exchange coupling magnetic field (exchange anisotropic magnetic field) is generated at the interface with and, for example, as shown in FIGS. 7 and 8, the magnetization of the first pinned magnetic layer 12 is pinned in the Y direction in the drawing. . When the magnetization of the first pinned magnetic layer 12 is pinned in the Y direction in the drawing, the magnetization of the second pinned magnetic layer 14 that faces the non-magnetic intermediate layer 13 is set to that of the first pinned magnetic layer 12. It is fixed in an antiparallel state (ferri state) with the magnetization.

In such a spin-valve thin film magnetic element, the magnetization of the first pinned magnetic layer 12 and the magnetization of the second pinned magnetic layer 14 are stably kept in an antiparallel state as the exchange coupling magnetic field is larger. It is possible. In the spin-valve thin-film magnetic element of this example, the antiferromagnetic layer 11 has a high blocking temperature and generates a large exchange coupling magnetic field (exchange anisotropic magnetic field) at the interface with the first pinned magnetic layer 12. By using the above alloy, the magnetization states of the first pinned magnetic layer 12 and the second pinned magnetic layer 14 can be maintained thermally stable.

As described above, in such a spin-valve type thin film magnetic element, exchange coupling is achieved by keeping the film thickness ratio between the first pinned magnetic layer 12 and the second pinned magnetic layer 14 within an appropriate range. The magnetic field (Hex) can be increased, and the magnetizations of the first pinned magnetic layer 12 and the second pinned magnetic layer 14 can be kept in a thermally stable antiparallel state (ferri state),
Moreover, it is possible to obtain a good ΔMR (rate of change in resistance).

As shown in FIGS. 7 and 8, a nonmagnetic conductive layer 15 made of Cu or the like is formed on the second pinned magnetic layer 14, and further on the nonmagnetic conductive layer 15. Has a free magnetic layer 16 formed thereon. As shown in FIGS. 7 and 8, the free magnetic layer 16 is formed of two layers, and the layer 17 formed on the side in contact with the nonmagnetic conductive layer 15 is formed of a Co film. . The other layer 18 is made of a NiFe alloy, a CoFe alloy, a CoNiFe alloy, or the like. In addition,
The reason why the Co film layer 17 is formed on the side in contact with the nonmagnetic conductive layer 15 is that the nonmagnetic conductive layer 15 made of Cu is formed.
Diffusion of metal elements etc. at the interface with can be prevented.
This is because R (rate of change in resistance) can be increased. The soft magnetic layers 19, 19 are preferably formed of a NiFe alloy or the like.

The bias layers 130 and 130 are Pt, Pd, Ir, Rh and R, like the antiferromagnetic layer 11.
u, Os, Au, Ag, Cr, Ni, Ne, Ar, X
It is made of an alloy containing Mn and at least one or more elements of e and Kr. Under the influence of the bias magnetic field of the bias layer 130, the magnetization of the free magnetic layer 16 is magnetized in the X1 direction in the figure. The conductive layers 131 and 131 are made of Au,
It is preferably formed of W, Cr, Ta or the like.

In the spin-valve type thin film magnetic element shown in FIGS. 7 and 8, a sense current is applied from the conductive layers 131, 131 to the free magnetic layer 16, the non-magnetic conductive layer 15 and the second pinned magnetic layer 14. When a magnetic field is applied from the recording medium to the Y direction shown in FIGS. 7 and 8, the magnetization of the free magnetic layer 16 changes from the X1 direction to the Y direction, and the nonmagnetic conductive layer 15 and the free magnetic layer at this time change. 16, the non-magnetic conductive layer 15 and the second pinned magnetic layer 14
The scattering of conduction electrons depending on the spins at the interface between and changes the electrical resistance, and the leakage magnetic field from the recording medium is detected.

By the way, the sense current actually flows in the interface between the first pinned magnetic layer 12 and the non-magnetic intermediate layer 13 and the like. The first pinned magnetic layer 12 is not directly involved in ΔMR, and the first pinned magnetic layer 12 is for fixing the second pinned magnetic layer 14 involved in ΔMR in an appropriate direction.
It is, so to speak, a layer that played an auxiliary role. Therefore, the sense current flowing into the first pinned magnetic layer 12 and the non-magnetic intermediate layer 13 causes a shunt loss (current loss), but the amount of this shunt loss is very small, and the second embodiment is used. In, it is possible to obtain ΔMR which is almost the same as the conventional one.

The spin valve thin film magnetic element of this example is
The spin-valve thin-film magnetic element shown in FIG. 1 can be manufactured by almost the same manufacturing method. That is, in the method of manufacturing a spin-valve thin film magnetic element of the present invention, the antiferromagnetic layer 11, the first pinned magnetic layer 12, the non-magnetic intermediate layer 13, the second pinned magnetic layer 14, and the non-ferromagnetic layer 14 are formed on the substrate K. Magnetic conductive layer 15,
After forming the first laminated body by sequentially laminating the free magnetic layers 16, a first heat treatment temperature is applied to the first laminated body while applying a first magnetic field in a direction orthogonal to the track width Tw direction. Then, an exchange anisotropic magnetic field is generated in the antiferromagnetic layer 11 to fix the magnetization of the first pinned magnetic layer 12.

Next, a track width T is formed on the first laminate by a method using a lift-off resist.
The soft magnetic layers 19 and 19 are formed at an interval corresponding to w, the bias layers 130 and 130 are subsequently formed on the soft magnetic layers 19 and 19, and the bias layer 13 is further formed.
0 and 130, conductive layers 131 and 131 are formed, and
And a second laminated body having the same shape as the spin-valve type thin film magnetic element shown in FIG. 8 is obtained.

A second magnetic field smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 11 is applied to the second laminated body thus obtained in the track width Tw direction while applying the second magnetic field. 7 and 8 by applying a bias magnetic field to the free magnetic layer 16 in a direction intersecting the magnetization directions of the first pinned magnetic layer 12 and the second pinned magnetic layer 14 by performing a heat treatment at a heat treatment temperature. The spin valve thin film magnetic element shown is obtained.

Also in such a spin-valve type thin film magnetic element, the antiferromagnetic layer 11 and the bias layer 130 are
Pt, Pd, Rh, Ru, Ir, Os, Au, Ag, C
Since it is made of an alloy containing Mn and at least one element or two or more elements out of r, Ni, Ne, Ar, Xe, and Kr, the temperature characteristic of the exchange anisotropic magnetic field becomes good and the heat resistance is high. It is a spin-valve thin-film magnetic element with excellent characteristics. Also, it has excellent durability when equipped in a device such as a thin-film magnetic head whose temperature inside the device becomes high, and is an excellent spin-valve type in which fluctuation of the exchange anisotropic magnetic field (exchange coupling magnetic field) due to temperature change is small. It can be a thin film magnetic element. Furthermore, by forming the antiferromagnetic layer 11 from the above alloy, the blocking temperature becomes high and a large exchange anisotropic magnetic field can be generated in the antiferromagnetic layer 11, so that the first fixed magnetic The magnetization directions of the layer 12 and the second pinned magnetic layer 14 can be firmly pinned.

In the method of manufacturing the spin-valve thin film magnetic element, the antiferromagnetic layer 11 and the bias layer 130 have Pt, Pd, Rh, Ru, Ir, Os, and A.
An alloy containing at least one element of u, Ag, Cr, Ni, Ne, Ar, Xe, and Kr and Mn and Mn is used, and the first heat treatment is performed by utilizing the properties of the alloy. A direction in which the magnetization direction of the first pinned magnetic layer 12 is fixed and the magnetization direction of the free magnetic layer 16 intersects the magnetization directions of the first pinned magnetic layer 12 and the second pinned magnetic layer 14 by the second heat treatment. Therefore, the magnetization direction of the free magnetic layer 16 intersects the magnetization directions of the first pinned magnetic layer 12 and the second pinned magnetic layer 14 without adversely affecting the magnetization direction of the first pinned magnetic layer 12. Can be aligned in any direction,
It is possible to obtain a spin valve thin film magnetic element having excellent heat resistance.

Further, in the method of manufacturing the spin-valve thin film magnetic element, the soft magnetic layers 19 and 19 are formed on the first laminated body, and the bias layer 13 is formed on the soft magnetic layers 19 and 19.
0 and 130 are formed, the soft magnetic layer 19,
After forming 19, the bias layers 130 and 130 can be formed without breaking the vacuum, and it is not necessary to clean the surface on which the bias layers 130 and 130 are formed by ion milling or reverse sputtering. It is possible to provide an excellent manufacturing method that does not cause inconveniences caused by cleaning, such as contamination due to deposits and adverse effects on the generation of an exchange anisotropic magnetic field due to disturbance of the crystal state of the surface. In addition, the bias layers 130, 1
Since it is not necessary to clean the surface on which the bias layers 130, 130 are formed before forming 30, it can be easily manufactured.

[Third Embodiment] FIG. 9 shows a third embodiment of the present invention.
FIG. 10 is a transverse cross-sectional view schematically showing the spin-valve thin-film magnetic element of the embodiment of the present invention, and FIG. 10 shows the spin-valve thin-film magnetic element shown in FIG. 9 viewed from the side facing the recording medium. 3 is a cross-sectional view showing the structure of FIG. Also in the spin-valve thin-film magnetic element of this example, like the above-mentioned spin-valve thin-film magnetic element, it is provided at the trailing side end of the floating slider provided in the hard disk device, and the recording magnetic field of the hard disk etc. Is to detect. The moving direction of the magnetic recording medium such as a hard disk is the Z direction in the figure, and the direction of the leakage magnetic field from the magnetic recording medium is the Y direction.

Also, in the spin-valve type thin film magnetic element of this example, the magnetization direction of the free magnetic layer intersects with the magnetization direction of the pinned magnetic layer by the exchange bias method using the bias layer made of an antiferromagnetic material. It is aligned in the direction. In this spin-valve thin-film magnetic element, not only the fixed magnetic layer but also the free magnetic layer is divided into two layers of a first free magnetic layer and a second free magnetic layer via a non-magnetic intermediate layer.

In FIGS. 9 and 10, the symbol K indicates a substrate. An insulating underlayer 200 of Al ₂ O _3, etc., a lower shield layer 163, a lower gap layer 164, and an antiferromagnetic layer 51 are formed on the substrate K, and further on the antiferromagnetic layer 51. , First pinned magnetic layer 52, non-magnetic intermediate layer 53, second pinned magnetic layer 54, non-magnetic conductive layer 5
5, second free magnetic layer 56, non-magnetic intermediate layer 59, first
The free magnetic layer 60 is sequentially laminated. As shown in FIG. 10, soft magnetic layers 61, 61 are provided on the first free magnetic layer 60 with a space corresponding to the track width Tw. On the soft magnetic layers 61, 61,
Bias layers 62, 62 are provided, and the bias layer 6 is provided.
Conductive layers 63, 63 are formed on the layers 2, 62.

Also in the spin-valve thin-film magnetic element of the third embodiment of the present invention, the antiferromagnetic layer 51 includes Pt, Pd, R as in the spin-valve thin-film magnetic element.
h, Ru, Ir, Os, Au, Ag, Cr, Ni, N
at least one of e, Ar, Xe, and Kr or 2
The first fixed magnetic layer 52 and the second fixed magnetic layer 54 are magnetized in a fixed direction by heat treatment in a magnetic field.

The first pinned magnetic layer 52 and the second pinned magnetic layer 54 are formed of a Co film, a NiFe alloy, a CoFe alloy, a CoNiFe alloy, a CoNi alloy, or the like. The nonmagnetic intermediate layer 53 is made of Ru, Rh, I.
It is preferably formed of an alloy of one or more of r, Cr, Re and Cu.

The first pinned magnetic layer 52 is the antiferromagnetic layer 51.
And is annealed (heat-treated) in a magnetic field to form the first pinned magnetic layer 52 and the antiferromagnetic layer 51.
An exchange coupling magnetic field (exchange anisotropy magnetic field) is generated at the interface with, and, for example, as shown in FIG. 9 and FIG.
The magnetization of the pinned magnetic layer 22 is pinned in the Y direction in the figure.
When the magnetization of the first pinned magnetic layer 52 is pinned in the Y direction in the drawing, the magnetization of the second pinned magnetic layer 54 that faces the non-magnetic intermediate layer 53 is the same as that of the first pinned magnetic layer 52. It is fixed in an antiparallel state (ferri state) with the magnetization.

In order to maintain the stability of this ferri state,
A large exchange coupling field is needed. In the spin-valve thin-film magnetic element of this example, the antiferromagnetic layer 51 has a high blocking temperature and generates a large exchange coupling magnetic field (exchange anisotropic magnetic field) at the interface with the first pinned magnetic layer 52. By using the above alloy, the magnetization states of the first pinned magnetic layer 52 and the second pinned magnetic layer 54 can be maintained thermally stable. In addition, the non-magnetic conductive layer 55
Is preferably formed of Cu or the like.

The first free magnetic layer 56 is formed of two layers as shown in FIGS. 9 and 10, and the Co film 57 is formed on the side in contact with the nonmagnetic conductive layer 55. . The reason why the Co film 57 is formed on the side in contact with the nonmagnetic conductive layer 55 is to first increase ΔMR and secondly to prevent diffusion with the nonmagnetic conductive layer 55.

A NiFe alloy film 58 is formed on the Co film 57. Further, the NiFe alloy film 58
A nonmagnetic intermediate layer 59 is formed on the top. And
The first free magnetic layer 6 is formed on the non-magnetic intermediate layer 59.
0 is formed. The first free magnetic layer 60 is
Co film, NiFe alloy, CoFe alloy, or CoN
It is formed of an iFe alloy, a CoNi alloy, or the like.

Further, the non-magnetic intermediate layer 59 interposed between the second free magnetic layer 56 and the first free magnetic layer 60 is
It is preferable to be formed of an alloy of one or more of Ru, Rh, Ir, Cr, Re and Cu.

The magnetization of the second free magnetic layer 56 and the first
The magnetization of the free magnetic layer 60 is as shown in FIGS. 9 and 10 by the exchange coupling magnetic field (RKKY interaction) generated between the second free magnetic layer 56 and the first free magnetic layer 60. In addition, they are antiparallel to each other (ferry state).

In the spin-valve thin film magnetic element shown in FIGS. 9 and 10, for example, the film thickness tF ₂ of the second free magnetic layer 56 is formed smaller than the film thickness tF _{1 of} the first free magnetic layer 60. Has been done. The Ms · tF ₂ of the second free magnetic layer 56 is M of the first free magnetic layer 60.
The bias layer 6 is set to be smaller than s · tF _1.
When a bias magnetic field is applied from 2 in the direction opposite to the X1 direction in the figure, the first free magnetic layer 60 having a large Ms · tF ₁ is obtained.
The magnetization of the
The first free magnetic layer 6 aligned in a direction opposite to the direction.
By the exchange coupling magnetic field (RKKY interaction) with 0, M
The magnetization of the second free magnetic layer 56 having a small s · tF ₂ is
They are aligned in the X1 direction shown.

When an external magnetic field enters from the Y direction in the drawing, the magnetizations of the second free magnetic layer 56 and the first free magnetic layer 60 are affected by the external magnetic field while maintaining the ferrimagnetic state. Rotate. Then, depending on the relationship between the variable magnetization of the second free magnetic layer 56 that gives an adverse effect on ΔMR and the fixed magnetization of the second fixed magnetic layer 54 (eg, magnetized in the direction opposite to the Y direction in the drawing), the electric The resistance changes and the external magnetic field is detected as a change in electrical resistance.

The soft magnetic layers 61, 61 are made of, for example, Ni.
It is preferably formed of an Fe alloy or the like. In addition, the bias layers 62 and 62 have the same structure as the antiferromagnetic layer 51.
t, Pd, Rh, Ru, Ir, Os, Au, Ag, C
It is made of an alloy containing Mn and at least one element selected from r, Ni, Ne, Ar, Xe, and Kr. The conductive layers 62 and 63 are made of Au,
It is preferably formed of W, Cr, Ta or the like.

The spin valve thin film magnetic element of this example also
The spin-valve thin-film magnetic element shown in FIG. 1 can be manufactured by almost the same manufacturing method. That is, in the method of manufacturing a spin-valve thin film magnetic element of the present invention, the antiferromagnetic layer 51, the first pinned magnetic layer 52, the non-magnetic intermediate layer 53, the second pinned magnetic layer 54, and the non-ferromagnetic layer 54 are formed on the substrate K. Magnetic conductive layer 55,
After the second free magnetic layer 56, the non-magnetic intermediate layer 59, and the first free magnetic layer 60 are sequentially stacked to form a first stacked body, the first stacked body is orthogonal to the track width Tw direction. Direction, a first magnetic field is applied and heat treatment is performed at a first heat treatment temperature to generate an exchange anisotropic magnetic field in the antiferromagnetic layer 51, and the magnetization of the first fixed magnetic layer 52 is fixed. To do.

Next, a track width T is formed on the first laminate by a method using a lift-off resist.
The soft magnetic layers 61, 61 are formed at intervals corresponding to w, the bias layers 62, 62 are subsequently formed on the soft magnetic layers 61, 61, and the bias layers 62, 62 are further formed.
Conductive layers 63, 63 are formed on top of the above to obtain a second laminated body having the same shape as the spin-valve type thin film magnetic element shown in FIGS. 9 and 10.

A second magnetic field smaller than the exchange anisotropic magnetic field of the antiferromagnetic layer 51 is applied to the second laminate thus obtained in the track width Tw direction while applying the second magnetic field. The first free magnetic layer 60 is heat-treated at a heat treatment temperature to form the first pinned magnetic layer 52 and the second pinned magnetic layer 54.
The spin valve thin film magnetic element shown in FIGS. 9 and 10 is obtained by applying a bias magnetic field in a direction intersecting with the magnetization direction of.

Also in such a spin-valve type thin film magnetic element, the antiferromagnetic layer 51 and the bias layer 62 are P
t, Pd, Rh, Ru, Ir, Os, Au, Ag, C
Since it is made of an alloy containing Mn and at least one element or two or more elements out of r, Ni, Ne, Ar, Xe, and Kr, the temperature characteristic of the exchange anisotropic magnetic field becomes good and the heat resistance is high. It is a spin-valve thin-film magnetic element with excellent characteristics.

Further, the durability is good when the device is provided in a device such as a thin-film magnetic head in which the element becomes high temperature due to the Joule heat due to the sense current flowing through the element in the hard disk device, and the replacement anisotropy due to the temperature change is high. It is possible to provide an excellent spin-valve thin-film magnetic element in which the fluctuation of the magnetic field (exchange coupling magnetic field) is small. Furthermore, the antiferromagnetic layer 5
When 1 is formed of the above alloy, the blocking temperature becomes high, and a large exchange anisotropic magnetic field can be generated in the antiferromagnetic layer 51. Therefore, the first pinned magnetic layer 5
The magnetization directions of the second and second pinned magnetic layers 54 can be firmly pinned.

In the method of manufacturing the spin-valve thin film magnetic element, the antiferromagnetic layer 51 and the bias layer 62 have Pt, Pd, Rh, Ru, Ir, Os and A.
An alloy containing at least one element of u, Ag, Cr, Ni, Ne, Ar, Xe, and Kr and Mn and Mn is used, and the first heat treatment is performed by utilizing the properties of the alloy. The magnetization direction of the first pinned magnetic layer 52 is fixed, and the magnetization direction of the first free magnetic layer 60 is set to the magnetization directions of the first pinned magnetic layer 52 and the second pinned magnetic layer 54 by the second heat treatment. Since they are aligned in the intersecting direction, the first pinned magnetic layer 5
The magnetization directions of the second free magnetic layer 56 and the first free magnetic layer 60 intersect the magnetization directions of the first pinned magnetic layer 52 and the second pinned magnetic layer 54 without adversely affecting the magnetization direction of No. 2. It is possible to obtain a spin-valve type thin film magnetic element having excellent heat resistance.

Further, in the method of manufacturing the spin-valve thin film magnetic element, the soft magnetic layers 61, 61 are formed on the first laminated body, and the bias layer 6 is formed on the soft magnetic layers 61, 61.
2 and 62, the soft magnetic layers 61 and 6 are formed.
1, the bias layer 6 is formed without breaking the vacuum.
2, 62 can be formed, and the bias layer 62,
Since it is not necessary to clean the surface on which 62 is formed by ion milling or reverse sputtering, it is caused by cleaning such as contamination by redeposited substances and adverse effects on generation of exchange anisotropic magnetic field due to disorder of crystal state of the surface. It is possible to obtain an excellent manufacturing method that does not cause the inconvenience. Further, since it is not necessary to clean the surface on which the bias layers 62, 62 are formed before forming the bias layers 62, 62, there is a feature that they can be easily manufactured.

[Operation of Sense Current Magnetic Field] Next, the operation of the sense current magnetic field in the structures of the second and third embodiments shown in FIGS. 7 to 10 will be described. In the spin valve thin film magnetic element shown in FIGS. 7 and 8,
The second pinned magnetic layer 14 is formed below the nonmagnetic conductive layer 15. In this case, the first pinned magnetic layer 1
Of the second and second pinned magnetic layers 14, the direction of the sense current magnetic field is aligned with the magnetization direction of the pinned magnetic layer having the larger magnetic moment.

As shown in FIG. 7, the magnetic moment of the second pinned magnetic layer 14 is larger than that of the first pinned magnetic layer 12, and the second pinned magnetic layer 14 has a larger magnetic moment.
Has a magnetic moment in the direction opposite to the Y direction in the drawing (left direction in the drawing). Therefore, the first pinned magnetic layer 12
And the magnetic moment of the second pinned magnetic layer 14 are added together, and the combined magnetic moment is directed in the direction opposite to the Y direction in the drawing (left direction in the drawing).

As described above, the non-magnetic conductive layer 15 is the second magnetic layer.
Is formed above the pinned magnetic layer 14 and the first pinned magnetic layer 12. Therefore, the sense current magnetic field formed mainly by the sense current 112 flowing mainly around the non-magnetic conductive layer 15 is located below the non-magnetic conductive layer 15 so as to be directed to the left in the figure. Current 11
It suffices to control the flowing direction of 2. By doing so, the direction of the combined magnetic moment of the first pinned magnetic layer 12 and the second pinned magnetic layer 14 and the direction of the sense current magnetic field coincide with each other.

As shown in FIG. 7, the sense current 112
Are made to flow in the X1 direction in the figure. According to the right-handed screw law, the sense current magnetic field formed by passing the sense current is formed clockwise with respect to the paper surface. Therefore, a sense current magnetic field in the illustrated direction (opposite to the Y direction in the drawing) is applied to the layer below the nonmagnetic conductive layer 15, and the sense current causes the first combined magnetic moment to be generated. The exchange coupling magnetic field (RKK) that acts in the reinforcing direction and acts between the first pinned magnetic layer 12 and the second pinned magnetic layer 14
(Y interaction) is amplified, and the antiparallel state of the magnetization of the first pinned magnetic layer 12 and the magnetization of the second pinned magnetic layer 14 can be more thermally stabilized.

Particularly, when a sense current of 1 mA is applied, about 30
It is known that a sense current magnetic field of about (Oe) is generated and the element temperature rises by about 10 ° C. Furthermore, the number of rotations of the recording medium increases to about 10,000 rpm,
Due to this increase in the number of rotations, the internal temperature of the equipment is about 100 at maximum.
Rises to ℃. Therefore, for example, the sense current is set to 10
When mA is applied, the element temperature of the spin-valve thin film magnetic element rises to about 200 ° C., and the sense current magnetic field also increases to 300 (Oe).

In such an extremely high environmental temperature and when a large sense current flows, the first
If the direction of the combined magnetic moment that can be obtained by adding the magnetic moment of the pinned magnetic layer 12 and the second pinned magnetic layer 14 is opposite to the direction of the sense current magnetic field, the first pinned magnetic layer The antiparallel state between the magnetization of the layer 12 and the magnetization of the second pinned magnetic layer 14 is easily broken. Further, in order to withstand even a high environmental temperature, it is necessary to use an antiferromagnetic material having a high blocking temperature as the antiferromagnetic layer 11 in addition to adjusting the direction of the sense current magnetic field. Therefore, in the present invention, the above alloy having a high blocking temperature is used.

The composite magnetic moment formed by the magnetic moment of the first pinned magnetic layer 12 and the magnetic moment of the second pinned magnetic layer 14 shown in FIG. 7 is directed rightward in the drawing (Y direction in the drawing). In this case, the sense current may flow in the direction opposite to the X1 direction in the drawing so that the sense current magnetic field is formed counterclockwise with respect to the plane of the drawing.

9 and 10 show a spin valve thin film magnetic element formed by dividing a free magnetic layer into two layers, a first free magnetic layer and a second free magnetic layer, with a nonmagnetic intermediate layer interposed therebetween. However, like the spin valve thin film magnetic element shown in FIG. 9, the first pinned magnetic layer 52 and the second pinned magnetic layer 54 are formed below the non-magnetic conductive layer 55. In that case, the sense current direction may be controlled in the same manner as in the case of the spin valve thin film magnetic element shown in FIG.

As described above, according to each of the above embodiments, the direction of the sense current magnetic field formed by flowing the sense current, the magnetic moment of the first pinned magnetic layer and the second pinned magnetic layer. By matching the directions of the synthetic magnetic moments that can be obtained by adding the magnetic moments of the above, the exchange coupling magnetic field (RKKY interaction) acting between the first pinned magnetic layer and the second pinned magnetic layer can be obtained. It is possible to amplify and maintain the antiparallel state (ferri state) of the magnetization of the first pinned magnetic layer and the magnetization of the second pinned magnetic layer in a thermally stable state.

In particular, in this embodiment, an antiferromagnetic material having a high blocking temperature is used for the antiferromagnetic layer in order to further improve thermal stability. Even if the magnetization is significantly increased, the antiparallel state (ferri state) of the magnetization of the first pinned magnetic layer and the magnetization of the second pinned magnetic layer can be hardly broken.

Further, if an attempt is made to increase the read current by increasing the sense current amount in order to cope with the higher recording density, the sense current magnetic field also increases accordingly. However, in the embodiment of the present invention, the sense current is increased. Since the magnetic field has the effect of amplifying the exchange coupling magnetic field that acts between the first pinned magnetic layer and the second pinned magnetic layer, the increase in the sense current magnetic field causes the first pinned magnetic layer and the second pinned magnetic layer to move. The magnetization state of the pinned magnetic layer becomes more stable.

The control of the sense current direction can be applied regardless of what antiferromagnetic material is used for the antiferromagnetic layer. For example, the antiferromagnetic layer and the pinned magnetic layer (first
It does not matter whether heat treatment is necessary or not in order to generate an exchange coupling magnetic field (exchange anisotropic magnetic field) at the interface with the fixed magnetic layer). Further, as in the first embodiment shown in FIG. 1, even in the case of a single spin-valve thin film magnetic element in which the pinned magnetic layer is formed of a single layer, it is formed by flowing the above-mentioned sense current. The magnetization of the pinned magnetic layer can be thermally stabilized by matching the direction of the sense current magnetic field generated with the magnetization direction of the pinned magnetic layer.

[Fourth Embodiment] FIG. 11 shows a fourth embodiment of the present invention.
FIG. 6 is a cross-sectional view showing the structure of the spin-valve thin-film magnetic element of the embodiment as viewed from the side facing the recording medium.
Also in this spin-valve thin-film magnetic element, like the spin-valve thin-film magnetic element shown in FIG. 1, it is provided at the trailing side end of the floating slider provided in the hard disk drive, and the recording magnetic field of the hard disk or the like. Is to detect. The moving direction of the magnetic recording medium such as a hard disk is the Z direction in the figure, and the direction of the leakage magnetic field from the magnetic recording medium is the Y direction.

Also, in the spin-valve type thin film magnetic element of this example, the magnetization direction of the free magnetic layer intersects with the magnetization direction of the pinned magnetic layer by the exchange bias method using the bias layer made of an antiferromagnetic material. It is aligned in the direction. In this spin-valve thin-film magnetic element, not only the fixed magnetic layer but also the free magnetic layer is divided into two layers of a first free magnetic layer and a second free magnetic layer via a non-magnetic intermediate layer.

In FIG. 11, reference numeral K indicates a substrate. On the substrate K, as in the case of the third embodiment shown in FIG. 10, the insulating underlayer 20 such as Al ₂ O _{3 is used.}
0, a lower shield layer 163, a lower gap layer 164, and an antiferromagnetic layer 51 are formed, and further, on the antiferromagnetic layer 51, a first pinned magnetic layer 52, a nonmagnetic intermediate layer 53, and a second magnetic layer. Pinned magnetic layer 54, non-magnetic conductive layer 55, second free magnetic layer 56, non-magnetic intermediate layer 59, first free magnetic layer 6 of
0 is sequentially stacked. The second free magnetic layer 60
In this case, concave portions 60a, 60a are formed on both sides of a portion corresponding to the track width of the central portion thereof.
The soft magnetic layers 61 and 61 have track width T so as to embed a.
It is provided so as to open a space corresponding to w. Further, bias layers 62 and 62 are provided on the soft magnetic layers 61 and 61, and conductive layers 63 and 63 are formed on the bias layers 62 and 62.

Also in the spin-valve thin-film magnetic element of the fourth embodiment of the present invention, the antiferromagnetic layer 51 has Pt, Pd, R as in the spin-valve thin-film magnetic element.
h, Ru, Ir, Os, Au, Ag, Cr, Ni, N
at least one of e, Ar, Xe, and Kr or 2
It is composed of an alloy containing at least one element and Mn,
The first pinned magnetic layer 52 and the second pinned magnetic layer 54 are magnetized in a fixed direction by heat treatment in a magnetic field.

The first pinned magnetic layer 52 and the second pinned magnetic layer 54 are formed of a Co film, a NiFe alloy, a CoFe alloy, a CoNiFe alloy, a CoNi alloy, or the like. The nonmagnetic intermediate layer 53 is made of Ru, Rh, I.
It is preferably formed of an alloy of one or more of r, Cr, Re and Cu.

The first pinned magnetic layer 52 is the antiferromagnetic layer 51.
And is annealed (heat-treated) in a magnetic field to form the first pinned magnetic layer 52 and the antiferromagnetic layer 51.
An exchange coupling magnetic field (exchange anisotropy magnetic field) is generated at the interface with, and, for example, as shown in FIG. 11, the magnetization of the first pinned magnetic layer 52 is pinned in the Y direction in the drawing. When the magnetization of the first pinned magnetic layer 52 is pinned in the Y direction in the drawing,
The second pinned magnetic layer 5 that faces the non-magnetic intermediate layer 53.
The magnetization of No. 4 is pinned in an antiparallel state (ferri state) with the magnetization of the first pinned magnetic layer 52.

To maintain the stability of this ferri state,
A large exchange coupling field is needed. In the spin-valve thin-film magnetic element of this example, the antiferromagnetic layer 51 has a high blocking temperature and generates a large exchange coupling magnetic field (exchange anisotropic magnetic field) at the interface with the first pinned magnetic layer 52. By using the above alloy, the magnetization states of the first pinned magnetic layer 52 and the second pinned magnetic layer 54 can be maintained thermally stable. In addition, the non-magnetic conductive layer 55
Is preferably formed of Cu or the like.

As shown in FIG. 11, the second free magnetic layer 56 is composed of two layers, and the Co film 57 is formed on the side in contact with the nonmagnetic conductive layer 55. The reason why the Co film 57 is formed on the side in contact with the nonmagnetic conductive layer 55 is to first increase ΔMR and secondly to prevent diffusion with the nonmagnetic conductive layer 55.

A NiFe alloy film 58 is formed on the Co film 57. Further, the NiFe alloy film 58
A nonmagnetic intermediate layer 59 is formed on the top. And
The first free magnetic layer 6 is formed on the non-magnetic intermediate layer 59.
0 is formed. The first free magnetic layer 60 is
Co film, NiFe alloy, CoFe alloy, or CoN
It is formed of an iFe alloy, a CoNi alloy, or the like.

Further, the non-magnetic intermediate layer 59 interposed between the second free magnetic layer 56 and the first free magnetic layer 60 is
It is preferable to be formed of an alloy of one or more of Ru, Rh, Ir, Cr, Re and Cu.

The magnetization of the second free magnetic layer 56 and the first
The magnetization of the free magnetic layer 60 of the second free magnetic layer 56 is caused by the exchange coupling magnetic field (RKKY interaction) generated between the second free magnetic layer 56 and the first free magnetic layer 60, as shown in FIG. It is in an anti-parallel state (ferry state).

In the spin valve thin film magnetic element shown in FIG. 11, for example, the film thickness tF of the second free magnetic layer 56 is set.
₂ is formed to be smaller than the film thickness tF _{1 of} the first free magnetic layer 60, but the opposite relationship may be acceptable. The Ms · tF ₂ of the second free magnetic layer 56 is
It is set to be smaller than Ms · tF _{1 of} the first free magnetic layer 60, and when a bias magnetic field is applied from the bias layer 62 in the direction opposite to the X1 direction in the drawing, the first free magnetic layer having a large Ms · tF ₁ is obtained. The magnetization of 60 is aligned in the direction opposite to the X1 direction in the figure under the influence of the bias magnetic field, and the exchange coupling magnetic field (R
(KKY interaction) causes a small _second Ms · tF 2
The magnetization of the free magnetic layer 56 is aligned in the X1 direction in the figure.

When an external magnetic field enters from the Y direction shown in the figure, the magnetizations of the second free magnetic layer 56 and the first free magnetic layer 60 are affected by the external magnetic field while maintaining the ferrimagnetic state. Rotate. Then, depending on the relationship between the variable magnetization of the second free magnetic layer 56 that gives an adverse effect on ΔMR and the fixed magnetization of the second fixed magnetic layer 54 (eg, magnetized in the direction opposite to the Y direction in the drawing), the electric The resistance changes and the external magnetic field is detected as a change in electrical resistance.

The soft magnetic layers 61, 61 are made of, for example, Ni.
It is preferably formed of an Fe alloy or the like. In addition, the bias layers 62 and 62 have the same structure as the antiferromagnetic layer 51.
t, Pd, Rh, Ru, Ir, Os, Au, Ag, C
It is made of an alloy containing Mn and at least one element selected from r, Ni, Ne, Ar, Xe, and Kr. The conductive layers 62 and 63 are made of Au,
It is preferably formed of W, Cr, Ta or the like.

The spin-valve type thin film magnetic element of this example also
The spin-valve thin-film magnetic element shown in FIG. 10 can be manufactured by almost the same manufacturing method. That is, in the method of manufacturing a spin-valve thin film magnetic element of the present invention, the antiferromagnetic layer 51, the first pinned magnetic layer 52, the non-magnetic intermediate layer 53, the first pinned magnetic layer 54, and the non-ferromagnetic layer 54 are formed on the substrate K. Magnetic conductive layer 55,
After the second free magnetic layer 56, the non-magnetic intermediate layer 59, and the second free magnetic layer 60 are sequentially stacked to form the first stacked body, the first stacked body is orthogonal to the track width Tw direction. Direction, a first magnetic field is applied and heat treatment is performed at a first heat treatment temperature to generate an exchange anisotropic magnetic field in the antiferromagnetic layer 51, and the magnetization of the first fixed magnetic layer 52 is fixed. To do.

Next, as shown in FIG. 12, a lift-off resist 350 having a width corresponding to the track width is used on the first laminate, and a part of the first free magnetic layer is subjected to ion milling or the like. The recesses 60a, 60a are formed by, for example, removing a fraction of the first free magnetic layer by a method, and then the recesses 60a are formed at intervals corresponding to the track width Tw.
Soft magnetic layers 61, 61 are formed so as to be embedded therein, and then bias layers 62, 6 are formed on the soft magnetic layers 61, 61.
2 is further formed, and conductive layers 63 and 63 are further formed on the bias layers 62 and 62 to obtain a laminated body having the same shape as the spin valve thin film magnetic element of the previous embodiment.

At the second heat treatment temperature, a second magnetic field smaller than the exchange anisotropy magnetic field of the antiferromagnetic layer 51 was applied to the laminate thus obtained in the track width Tw direction. The spin valve type shown in FIG. 11 is obtained by heat-treating and applying a bias magnetic field to the first free magnetic layer 60 in a direction intersecting the magnetization directions of the first pinned magnetic layer 52 and the second pinned magnetic layer 54. A thin film magnetic element is obtained.

Also in such a spin-valve thin film magnetic element, the antiferromagnetic layer 51 and the bias layer 62 are made of P.
t, Pd, Rh, Ru, Ir, Os, Au, Ag, C
Since it is made of an alloy containing Mn and at least one element or two or more elements out of r, Ni, Ne, Ar, Xe, and Kr, the temperature characteristic of the exchange anisotropic magnetic field becomes good and the heat resistance is high. It is a spin-valve thin-film magnetic element with excellent characteristics.

Also, the durability is good when the device is provided in a device such as a thin film magnetic head in which the element becomes high temperature due to the Joule heat due to the sense current flowing through the element in the hard disk device, and the replacement anisotropy due to the temperature change. It is possible to provide an excellent spin-valve thin-film magnetic element in which the fluctuation of the magnetic field (exchange coupling magnetic field) is small. Furthermore, the antiferromagnetic layer 5
When 1 is formed of the above alloy, the blocking temperature becomes high, and a large exchange anisotropic magnetic field can be generated in the antiferromagnetic layer 51. Therefore, the first pinned magnetic layer 5
The magnetization directions of the second and second pinned magnetic layers 54 can be firmly pinned.

In the method of manufacturing the spin-valve thin-film magnetic element, the antiferromagnetic layer 51 and the bias layer 62 have Pt, Pd, Rh, Ru, Ir, Os, and A.
An alloy containing at least one element of u, Ag, Cr, Ni, Ne, Ar, Xe, and Kr and Mn and Mn is used, and the first heat treatment is performed by utilizing the properties of the alloy. The magnetization direction of the first pinned magnetic layer 52 is fixed, and the magnetization direction of the first free magnetic layer 60 is set to the magnetization directions of the first pinned magnetic layer 52 and the second pinned magnetic layer 54 by the second heat treatment. Since they are aligned in the intersecting direction, the first pinned magnetic layer 5
The magnetization directions of the second free magnetic layer 56 and the first free magnetic layer 60 intersect the magnetization directions of the first pinned magnetic layer 52 and the second pinned magnetic layer 54 without adversely affecting the magnetization direction of No. 2. It is possible to obtain a spin-valve type thin film magnetic element having excellent heat resistance.

[0223]

EXAMPLE A spin-valve type thin film magnetic element having the structure shown in FIGS. 1 and 2 was used as a lower shield layer (Co-Nb-Zr).
System amorphous alloy) and the lower gap layer (Al ₂ O ₃ ) were formed on the AlTiC (Al ₂ O ₃ —TiC) substrate. The thickness consisting Pt ₅₀ Mn ₅ first pinned magnetic layer having a thickness of 15 Å ₀ of an antiferromagnetic layer and Co with a thickness of 150Å formed of a non-magnetic intermediate layer having a thickness of 8Å of Ru and Co on the substrate 25 Å second pinned magnetic layer and thickness 2 consisting of Cu
A non-magnetic conductive layer having a thickness of 5 Å is laminated, and a second free magnetic layer having a thickness of 40 Å made of a Ni ₈₀ Fe ₂₀ alloy (saturation magnetization Ms × thickness t = 7.16 × 10 ⁻⁴ T · nm). And a non-magnetic intermediate layer made of Ru with a thickness of 8Å and a first free magnetic layer made of Ni ₈₀ Fe ₂₀ alloy with a thickness of 25Å (saturation magnetization Ms ×
Thus, a laminated body having a film thickness t = 4.52 × 10 ⁻⁴ T · nm) was obtained. The width of both free magnetic layers along the track width direction is 0.6 μm, and the width on the element height side orthogonal to the track width direction is 0.4 μm. Ni ₈₀ Fe _{20 is provided on} both sides of the free magnetic layer so as to be in contact with the first free magnetic layer. A soft magnetic layer made of an alloy having a thickness of 20 Å, an antiferromagnetic layer made of a Pt ₅₄ Mn ₄₆ alloy having a thickness of 300 Å, and a conductive layer made of Cr having a thickness of 1000 Å were laminated. Here, in the above-mentioned laminated structure, the antiparallel coupling magnetic field between the first free magnetic layer and the second free magnetic layer is 58.
It was 4 kA / m.

Next, as a comparative example, an antiferromagnetic layer, a first pinned magnetic layer, a non-magnetic intermediate layer, a second pinned magnetic layer, a non-magnetic conductive layer, a second free magnetic layer and a non-magnetic intermediate layer. And the first free magnetic layer have the same structure as described above, and a hard bias layer (saturated with Co ₈₅ Pt ₁₅₎ (saturated) is formed on both right and left sides of this laminate through a non-magnetic layer of Cr having a thickness of 20Å. Magnetization Ms × film thickness t = 1.88 × 10 ⁻³ T · nm) was formed. In the above configuration, the magnetization directions of the first free magnetic layer and the second free magnetic layer in the structure of the example obtained by magnetic simulation are shown in FIG. 25 as the directions along the film surface, and are compared. FIG. 20 shows the magnetization direction of the first free magnetic layer and the magnetization direction of the second free magnetic layer in the example structure as the directions along the film surface.
In the laminated structure of the present invention, as shown by the arrow in FIG. 25, the longitudinal bias can be applied only to the first free magnetic layer, and the periphery of both the first free magnetic layer and the second free magnetic layer can be applied. A region where the magnetization direction is disturbed is not generated in the part. That is, by adopting the structure of the present invention, unlike the conventional structure shown in FIG. 20, magnetic competition (frustration) occurs.
It is clear that the magnetization distribution is eliminated and the magnetization distribution is uniform in both the first free magnetic layer and the second free magnetic layer. On the other hand, the arrow indicating the direction of magnetization shown in FIG.
A strong reverse magnetic field is applied from the hard bias films on both the left and right ends of the free magnetic layer and competes with the exchange coupling magnetic field that the second free magnetic layer tries to act, so that the magnetization direction is disturbed on both ends. It is clear that As a result, the magnetization direction of the second free magnetic layer is also disturbed, resulting in problems such as Barkhausen noise, which may impair magnetic stability.

Asymmetry in the track width direction (asymmetry of reproduced waveform) in the magnetic head equipped with these elements
The profile of 0.1 × 1 recorded on the recording medium
The measurement was performed by scanning a magnetic track on a micro track pattern having a width of 0 ^-6 m (μm). This result is shown in FIG. 26 (asymmetry of the conventional magnetic head) and FIG.
(Asymmetry of the magnetic head of the present invention). In FIG. 26 showing the measurement result of the conventional example, it is found that the asymmetry is abnormally large near both ends of the track. This is because the magnetization of the second free magnetic layer is near the both ends of the track as shown in FIG. It is related to the fact that it is disordered and largely collapsed from the relationship close to the magnetization of the second pinned magnetic layer, which is almost orthogonal. On the other hand, in FIG. 27 showing the example of the present invention, it is clear that a stable waveform is obtained without such a large change in asymmetry at both ends of the track.

[0226]

As described above in detail, in the spin valve thin film magnetic element of the present invention, the antiferromagnetic layer and the bias layer are made of an alloy represented by the composition formula Pt _m Mn _100-m , M indicating the composition ratio of the alloy forming the bias layer
Is 52 at% ≦ m ≦ 60 at%, and m representing the composition ratio of the alloy forming the antiferromagnetic layer is 48 at% ≦ m ≦ 5.
Since the content is 8 atomic%, the temperature characteristic of the exchange anisotropic magnetic field becomes good, and the spin valve thin film magnetic element excellent in heat resistance can be obtained. Also, the durability is good when equipped in a device such as a thin-film magnetic head whose temperature inside the device becomes high, and the exchange anisotropic magnetic field (exchange coupling magnetic field) due to temperature change.
It is possible to obtain an excellent spin-valve thin-film magnetic element with a small fluctuation of Furthermore, by forming the antiferromagnetic layer with the above alloy, the blocking temperature becomes high,
Since a large exchange anisotropic magnetic field can be generated in the antiferromagnetic layer, the spin-valve thin-film magnetic element can firmly fix the magnetization direction of the pinned magnetic layer.

In the above spin-valve thin film magnetic element, at least one of the pinned magnetic layer and the free magnetic layer is divided into two via the non-magnetic intermediate layer,
It may be characterized in that the separated layers are in a ferrimagnetic state in which the directions of magnetization are antiparallel.
In the case of a spin valve thin film magnetic element in which at least the pinned magnetic layer is divided into two via a non-magnetic intermediate layer, one of the pinned magnetic layers divided into two has the other pinned magnetic layer in the proper direction. The pinned magnetic layer can be kept in a very stable state. on the other hand,
When at least the free magnetic layer is divided into two via a non-magnetic intermediate layer to form a spin-valve thin film magnetic element, an exchange coupling magnetic field is generated between the two divided free magnetic layers, and a ferrimagnetic state is generated. Therefore, the magnetic field can be inverted with high sensitivity to the external magnetic field.

Since the thin-film magnetic head of the present invention comprises the above spin-valve thin-film magnetic element on the slider, it is excellent in durability and heat resistance, and a sufficient exchange anisotropic magnetic field can be obtained. It is possible to obtain a highly reliable thin film magnetic head.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a structure of a spin valve thin film magnetic element according to a first embodiment of the present invention when viewed from a side facing a recording medium.

FIG. 2 is a cross-sectional view showing the method of manufacturing the spin-valve thin film magnetic element shown in FIG. 1, showing a state in which a first stacked body is formed on a substrate.

FIG. 3 is a view for explaining the method of manufacturing the spin-valve thin film magnetic element shown in FIG. 1, and a cross-sectional view showing a state in which a lift-off resist is formed.

FIG. 4 is a cross-sectional view for explaining the method of manufacturing the spin-valve thin-film magnetic element shown in FIG. 1, showing a state in which a bias layer and a conductive layer are formed.

FIG. 5 is a perspective view showing a thin film magnetic head including a spin valve thin film magnetic element according to the first embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a main part of a thin film magnetic head including a spin valve thin film magnetic element according to the first embodiment of the present invention.

FIG. 7 is a sectional view showing a spin-valve thin film magnetic element according to a second embodiment of the present invention.

8 is a cross-sectional view showing the structure of the spin-valve thin-film magnetic element shown in FIG. 7 when viewed from the side facing a recording medium.

FIG. 9 is a sectional view showing a spin-valve thin film magnetic element according to a third embodiment of the present invention.

10 is a cross-sectional view showing the structure of the spin-valve thin-film magnetic element shown in FIG. 9 when viewed from the side facing the recording medium.

FIG. 11 is a cross-sectional view showing the structure of a spin valve thin film magnetic element according to a fourth embodiment of the present invention when viewed from the side facing a recording medium.

12 is a cross-sectional view showing a state in which a lift-off resist is formed on the first free magnetic layer to manufacture the structure shown in FIG.

FIG. 13 is a cross-sectional view showing the structure of an example of a conventional spin-valve thin-film magnetic element when viewed from the side facing a recording medium.

FIG. 14 is a cross-sectional view showing the structure of another example of the conventional spin-valve thin-film magnetic element when viewed from the side facing the recording medium.

FIG. 15 is a view for explaining the method of manufacturing the conventional spin-valve thin film magnetic element shown in FIG. 14, which is a cross-sectional view showing a state in which a first stacked body is formed on a substrate.

16 is a diagram for explaining a method of manufacturing the conventional spin-valve thin film magnetic element shown in FIG.
FIG. 6 is a cross-sectional view showing a state in which a lift-off resist is formed on the laminate.

FIG. 17 is a view for explaining the method of manufacturing the conventional spin valve thin film magnetic element shown in FIG. 14, which is a cross-sectional view showing a state in which a bias layer and a conductive layer are formed.

FIG. 18 is a sectional view showing another example of a conventional spin-valve type thin film magnetic element.

FIG. 19 shows a spin-valve type thin film magnetic element having the structure shown in FIG. 18, in which the free magnetic layer is divided into two layers, the magnetization direction of each layer of the two-layer free magnetic layer is determined by the strength of the external magnetic field. It is a figure shown according to.

20 is a diagram showing the magnetization directions of the first free magnetic layer and the second free magnetic layer in the spin-valve thin-film magnetic element having the structure shown in FIG.

FIG. 21: Pt _55.4 Mn _44.6 alloy and Pt
₅ is a graph showing the heat treatment temperature dependence of the exchange anisotropy magnetic field of an alloy having a composition of _54.4 Mn _45.6 .

FIG. 22 is a graph showing the Pt concentration (composition ratio m) dependence of the exchange anisotropy magnetic field of an alloy having a composition of Pt _m Mn _100-m .

FIG. 23 is a cross-sectional view showing a structure of an example of a spin-valve thin film magnetic element used for measuring the data of the graphs shown in FIGS. 21 and 22, as viewed from the side facing a recording medium. .

FIG. 24 is a cross-sectional view showing the structure of another example of the spin-valve thin-film magnetic element used for measuring the data of the graphs shown in FIGS. 21 and 22, as viewed from the side facing the recording medium. Is.

FIG. 25 is a diagram showing the magnetization directions of a first free magnetic layer and a second free magnetic layer in a spin valve thin film magnetic element adopting the structure of the present invention.

FIG. 26 is a diagram showing asymmetry of a magnetic head having a conventional structure.

FIG. 27 is a view showing asymmetry of a magnetic head adopting the structure of the present invention.

[Explanation of symbols]

1 Spin valve thin film magnetic element K board 2, 11, 22, 51 Antiferromagnetic layer 3, 23 pinned magnetic layer 4, 15, 24, 55 Non-magnetic conductive layer 5, 16, 25 Free magnetic layer 6, 26, 62, 130 Bias layer 8, 28, 63, 131 conductive layer 7, 19, 61 Soft magnetic layer Tw track width a1 first laminated body a2 Second laminated body 12, 52 First pinned magnetic layer 14, 54 Second pinned magnetic layer 13, 53 Non-magnetic intermediate layer 56 First Free Magnetic Layer 60 Second free magnetic layer 150 thin film magnetic head

Claims (10)

[Claims] 1. An antiferromagnetic layer, a pinned magnetic layer formed in contact with the antiferromagnetic layer and having a magnetization direction pinned by an exchange anisotropic magnetic field with the antiferromagnetic layer, and the pinned magnetic layer. A free magnetic layer formed over the non-magnetic conductive layer, a soft magnetic layer disposed on the free magnetic layer with a gap corresponding to the track width, and formed on the soft magnetic layer A spin valve thin film having a bias layer for aligning the magnetization direction of the free magnetic layer in a direction intersecting the magnetization direction of the pinned magnetic layer and a conductive layer for applying a detection current to the free magnetic layer on a substrate. A magnetic element, wherein the antiferromagnetic layer and the bias layer have a composition formula Pt _m
Mn consisting of alloys represented by Mn _100-m having different composition ratios, and _m representing the composition ratio of the alloy forming the bias layer is 52 atomic% ≦ m ≦ 60 atomic%, forming the antiferromagnetic layer. The alloy composition ratio m is 48 atom% ≤ m ≤ 58 atom%
A spin-valve thin-film magnetic element characterized by: 2. The composition ratio m of the bias layer is 52.
The spin valve thin film magnetic element according to claim 1, wherein atomic% ≤ m ≤ 54 atomic%. 3. The composition ratio m of the bias layer is 5
The spin valve thin film magnetic element according to claim 1, wherein 6.8 at% ≦ m ≦ 60 at%. 4. A ferrimagnetic state in which at least one of the pinned magnetic layer and the free magnetic layer is divided into two via a non-magnetic intermediate layer, and the directions of magnetization are antiparallel between the divided layers. The spin valve thin film magnetic element according to claim 1, wherein the spin valve thin film magnetic element is formed. 5. The pinned magnetic layer is divided into two via a non-magnetic intermediate layer, and the divided layers are in a ferrimagnetic state in which the directions of magnetization are antiparallel. Item 5. A spin valve thin film magnetic element according to any one of items 1 to 4. 6. The free magnetic layer is divided into two via a non-magnetic intermediate layer, and the divided layers are in a ferrimagnetic state in which the directions of magnetization are antiparallel. Item 5. A spin valve thin film magnetic element according to any one of items 1 to 4. 7. A recess is formed on both sides of a portion corresponding to the track width of the free magnetic layer, and soft magnetic layers are stacked so as to fill these recesses, and the soft magnetic layer is recessed in the free magnetic layer. 7. The spin-valve thin-film magnetic element according to claim 1, wherein the spin-valve thin-film magnetic element is directly bonded via the bottom surface, and a bias layer and a conductive layer are laminated on these soft magnetic layers. . 8. The spin valve thin film magnetic element according to claim 1, wherein the soft magnetic layer is made of a NiFe alloy. 9. The free magnetic layer is divided into two via a non-magnetic intermediate layer, and the free magnetic layer farther from the pinned magnetic layer is closer to the first free magnetic layer and the pinned magnetic layer. When the integrated free magnetic layer is the second free magnetic layer and the integrated value of the thickness of the magnetic layer and the value of the saturation magnetization is the magnetic film thickness, the magnetic film thickness of the first free magnetic layer. 9. The spin-valve thin-film magnetic element according to claim 1, wherein is a value different from the magnetic film thickness of the second free magnetic layer. 10. A thin film magnetic head comprising a slider equipped with the spin-valve thin film magnetic element according to claim 1. Description: