JP2003338644A - Magnetic detection element and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic detection element that appropriately and easily changes a free magnetic layer into a single magnetization domain and properly and easily controls a magnetizing direction, and promotes the achievement of a narrower track. <P>SOLUTION: The magnetizing direction of a ferromagnetic layer 24 is pinned by the exchange coupling magnetic field between a second antiferromagnetic layer 23 and the ferromagnetic layer 24, and the magnetizing direction of a free magnetic layer 26 is directed to a direction crossing the magnetizing direction of a pinned magnetic layer 28 by the RKKY mutual interaction of the ferromagnetic layer 24 and free magnetic layer 26 via a non-magnetic layer 25. Control in the magnetizing direction of the free magnetic layer 26 is adjusted by two stages of the intensity of the exchange coupled magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 and the intensity of the RKKY interaction between the ferromagnetic layer 24 and the free magnetic layer 26, thus easily carrying out fine control. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a magnetic detection element used in a magnetic sensor, a hard disk, etc. and a method of manufacturing the same, and in particular, it facilitates a narrow track width and improves a magnetic field detection capability. And a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 18 is a cross-sectional view of the structure of a conventional magnetic detecting element as viewed from the surface facing a recording medium.

The magnetic sensing element shown in FIG. 18 is called a spin valve type magnetic sensing element which is one type of GMR (giant magnetoresistive) element utilizing the giant magnetoresistive effect, and recording from a recording medium such as a hard disk. It detects a magnetic field.

This spin-valve type magnetic sensing element comprises a substrate 8, a first antiferromagnetic layer 1, a pinned magnetic layer (Pinn
ed) Magnetic layer) 2, non-magnetic material layer 3, free magnetic layer (Fre
e) a multilayer film 9 composed of 4; a pair of second antiferromagnetic layers 6 and 6 formed on the multilayer film 9; and a second antiferromagnetic layer 6 and 6 formed on the second antiferromagnetic layer 6 and 6. It is composed of a pair of electrode layers 7, 7.

The first antiferromagnetic layer 1 and the second antiferromagnetic layers 6 and 6 are made of Fe--Mn (iron-manganese) alloy film, Ni--.
Mn (nickel-manganese) alloy film or Pt-Mn
(Platinum-manganese) alloy film, fixed magnetic layer 2 and free magnetic layer 4 are Ni-Fe (nickel-iron) alloy film, non-magnetic material layer 3 is Cu (copper) film, and electrode layers 7 and 7 are Is Cr
Membranes are commonly used.

The magnetization of the pinned magnetic layer 2 is made into a single magnetic domain in the Y direction (the leakage magnetic field direction from the recording medium; the height direction) by the exchange anisotropic magnetic field with the first antiferromagnetic layer 1, and the free magnetic layer 4
It is desirable that the magnetization of (1) is aligned in the X direction under the influence of the exchange anisotropic magnetic field from the second antiferromagnetic layers 6 and 6.

That is, it is desirable that the magnetization of the pinned magnetic layer 2 and the magnetization of the free magnetic layer 4 be orthogonal to each other.

In this spin valve type magnetic sensing element, from the electrode layers 7 and 7 formed on the second antiferromagnetic layers 6 and 6,
A detection current (sense current) is applied to the free magnetic layer 4, the non-magnetic material layer 3 and the fixed magnetic layer 2. The running direction of a recording medium such as a hard disk is the Z direction, and when a leakage magnetic field from the recording medium is applied in the Y direction, the magnetization of the free magnetic layer 4 changes from the X direction to the Y direction. The electric resistance changes due to the relationship between the variation of the magnetization direction in the free magnetic layer 4 and the fixed magnetization direction of the fixed magnetic layer 2 (this is called the magnetoresistive effect), and the voltage based on the change in the electric resistance value. Due to the change, the leakage magnetic field from the recording medium is detected.

As means for applying a bias magnetic field to the free magnetic layer 4, a method shown in FIG.
There are various known methods such as the method shown in FIG.

[0010]

[Patent Document 1] USP 6,023,395

[0011]

When the spin-valve type magnetic sensing element of FIG. 18 is manufactured, after forming the multilayer film 9, a lift-off resist layer R is formed on the multilayer film 9 as shown in FIG. Then, the second antiferromagnetic layers 6 and 6 and the electrode layers 7 and 7 are formed by using the ion beam sputtering method or the like. On the resist layer R, layers 6a, 6a having the same composition as the second antiferromagnetic layers 6, 6 and layers 7a, 7a having the same composition as the electrode layers 7, 7 are formed.

Sputtered particles are less likely to be deposited in the region covered by the both ends of the resist layer R. Therefore, in the vicinity of the region covered by both ends of the resist layer R,
The second antiferromagnetic layers 6 and 6 and the electrode layers 7 and 7 are formed to have a small film thickness, and as shown in FIGS. 18 and 19, the films of the second antiferromagnetic layers 6 and 6 and the electrode layers 7 and 7 are formed. The dimension in the thickness direction is reduced at both sides S, S of the track.

Therefore, the effect of the exchange coupling magnetic field between the free magnetic layer 4 and the second antiferromagnetic layers 6 and 6 in the track side portions S and S is reduced. As a result, the magnetization directions of the track side portions S, S of the free magnetic layer 4 in FIG. 19 are not completely fixed in the X direction but change when an external magnetic field is applied.

In particular, when the track is narrowed in order to improve the recording density of the magnetic recording medium, not only the information of the magnetic recording track to be read within the area of the track width Tw, but also of the adjacent magnetic recording track. information,
There is a problem in that side reading may occur, that is, reading may be performed in the areas S and S on both sides of the track.

Further, in the structure in which the pair of second antiferromagnetic layers 6 and 6 are laminated on both end portions of the free magnetic layer 4 in the track width direction, a single magnetic domain in the center portion of the free magnetic layer 4 in the track width direction. Control of magnetization and magnetization direction is likely to be insufficient.

Therefore, as in the magnetic sensing element shown in FIG. 18, a pair of second antiferromagnetic layers 6 and 6 are laminated on both ends of the free magnetic layer 4 with a track width dimension. Instead, by stacking the second antiferromagnetic layer 10 on the entire upper surface of the free magnetic layer 4 as in the magnetic detecting element shown in FIG. 20, the region of the track width dimension Tw of the free magnetic layer 4 is made into a single magnetic domain. Therefore, a structure in which the magnetization direction is oriented in the direction perpendicular to the magnetization direction of the pinned magnetic layer 1 has been considered.

In order to make the region of the track width dimension Tw of the free magnetic layer 4 into a single magnetic domain and direct the magnetization direction to the direction orthogonal to the magnetization direction of the fixed magnetic layer 1, the free magnetic layer 4 is used.
It is necessary to increase the exchange coupling magnetic field between the second antiferromagnetic layer 10 and the second antiferromagnetic layer 10, but if this exchange coupling magnetic field becomes too large,
When the leakage magnetic field from the recording medium is applied in the Y direction, the magnetization of the free magnetic layer 4 does not change, and the magnetic detection capability is lost.

However, in the structure shown in FIG. 20, the magnetization direction of the free magnetic layer 4 is directed to the direction perpendicular to the magnetization direction of the pinned magnetic layer 1, and the magnetization direction of the free magnetic layer 4 is changed by the leakage magnetic field. It was very difficult to adjust the magnitude of the exchange coupling magnetic field between the free magnetic layer 4 and the antiferromagnetic layer 10 within such a range that it was possible, and it was not practical.

Further, in Patent Document 1, for example, a bias layer is provided on a free magnetic layer via a spacer layer, and an end portion in the track width direction of the bias layer and the free layer are formed. The magnetization of the free magnetic layer is set to a single magnetic domain by magnetostatic coupling between the ends of the magnetic layer in the track width direction. The method of aligning the magnetization of the free magnetic layer by using magnetostatic coupling between the ends with the bias layer as in Patent Document 1 is called the Instack bias method.

However, in the Instack bias method as disclosed in Patent Document 1, the thickness of the spacer layer is controlled so as to supply an appropriate bias magnetic field to the free magnetic layer, and the gap between the end portions of the free magnetic layer and the bias layer is controlled. This is all the more true in recent years when the control of the distance is extremely difficult and the element size is becoming smaller. In particular, the end of the free magnetic layer is more strongly affected by magnetostatic coupling than the center, so a uniform bias magnetic field is not supplied to the entire free magnetic layer, and the end of the free magnetic layer is strongly magnetized. This becomes a dead region, and as a result, the central portion of the free magnetic layer is also less likely to be inverted with respect to the external magnetic field due to the magnetization interaction inside the magnetic layer.

Further, in recent years when the element size has been narrowed, the bias magnetic field due to the magnetostatic coupling easily flows into not only the free magnetic layer but also other layers, which tends to adversely affect the reproducing characteristics. There is also.

Therefore, the present invention is to solve the above-mentioned conventional problems, and it is possible to appropriately and easily control the free magnetic layer into a single domain and control the magnetization direction, and to detect a narrow magnetic field. An object is to provide an element and a manufacturing method thereof.

[0023]

According to the present invention, there is provided a first antiferromagnetic layer, a fixed magnetic layer whose magnetization direction is fixed by the first antiferromagnetic layer, a nonmagnetic material layer, and a magnetization direction by an external magnetic field. In a magnetic detection element having a multilayer film having a free magnetic layer having a variable magnetic field, the pinned magnetic layer and the free magnetic layer have a ferromagnetic material layer made of a ferromagnetic material, and at least the track width region of the free magnetic layer is provided. A ferromagnetic layer and a second antiferromagnetic layer are laminated on an upper layer or a lower layer via a nonmagnetic layer, and the magnetization direction of the ferromagnetic layer is fixed by the exchange coupling magnetic field with the second antiferromagnetic layer. It is characterized in that it is oriented in a direction intersecting with the magnetization direction of the magnetic layer.

In the present invention, the magnetization direction of the ferromagnetic layer is directed to the direction crossing the magnetization direction of the pinned magnetic layer by the exchange coupling magnetic field with the second antiferromagnetic layer, and the free magnetic layer is Since the free magnetic layer is laminated on the ferromagnetic layer via the non-magnetic layer, the control of the single magnetic domain and the magnetization direction of the free magnetic layer depends on the magnitude of the exchange coupling magnetic field between the antiferromagnetic layer and the ferromagnetic layer. Since the magnitude of magnetic coupling between the ferromagnetic layer and the free magnetic layer is adjusted in two steps, fine control can be easily performed.

Therefore, according to the present invention, it is possible to appropriately and easily control the free magnetic layer to have a single magnetic domain and control the magnetization direction, so that further narrowing of the track of the magnetic detecting element can be promoted.

Further, in the present invention, even in the structure in which the ferromagnetic layer and the second antiferromagnetic layer are stacked on the track width region of the free magnetic layer with the nonmagnetic layer interposed therebetween, It is possible to reliably orient the magnetization direction in the direction perpendicular to the magnetization direction of the pinned magnetic layer and to change the magnetization direction of the free magnetic layer by the leakage magnetic field.

Therefore, in the present invention, the magnetization direction of the free magnetic layer is unlikely to be different between the central portion and both end portions of the track width region of the free magnetic layer.

In the present invention, the free magnetic layer is
It is preferable that a single magnetic domain is formed by an interlayer coupling magnetic field with the ferromagnetic layer via the non-magnetic layer, and a magnetization direction is oriented in a direction crossing the magnetization direction of the pinned magnetic layer.

For example, an RKKY interaction occurs between the free magnetic layer and the ferromagnetic layer via the nonmagnetic layer. As a result, the free magnetic layer becomes a single magnetic domain,
The magnetization direction is oriented in a direction intersecting with the magnetization direction of the pinned magnetic layer.

As described above, in the present invention, the free magnetic layer is controlled to have a single magnetic domain and the magnetization direction is controlled by the interlayer coupling magnetic field with the ferromagnetic layer via the non-magnetic layer. External magnetic fields such as
It is possible to prevent the longitudinal bias magnetic field applied to the free magnetic layer from being disturbed and disturbing the magnetic domain structure of the free magnetic layer.

In order to cause a stable RKKY interaction between the free magnetic layer and the ferromagnetic layer, the non-magnetic layer may be one of Ru, Rh, Ir, Cr, Re and Cu, or It is preferably formed of two or more alloys.

When the non-magnetic layer is made of Ru and the free magnetic layer and the ferromagnetic layer are made to have an artificial ferri state different from each other by 180 °, the Ru film thickness is 8Å to 11Å or 15Å ~. 21Å is preferable.

In the present invention, the exchange coupling magnetic field between the second antiferromagnetic layer and the ferromagnetic layer is increased so that the magnetization direction of the ferromagnetic layer is strongly fixed in the direction crossing the magnetization direction of the pinned magnetic layer. Then, the magnitude of the interlayer coupling magnetic field between the free magnetic layer and the ferromagnetic layer via the non-magnetic layer is made smaller than the exchange coupling magnetic field between the second antiferromagnetic layer and the ferromagnetic layer. Therefore, it is necessary to adjust the magnetization direction of the free magnetic layer to the direction perpendicular to the magnetization direction of the pinned magnetic layer without fail, and to adjust the magnetization direction of the free magnetic layer so that it can be changed by the leakage magnetic field. is there.

In order to increase the exchange coupling magnetic field between the second antiferromagnetic layer and the ferromagnetic layer and make the magnitude of the interlayer coupling magnetic field between the free magnetic layer and the ferromagnetic layer smaller than the exchange coupling magnetic field. In the present invention, the magnitude of the magnetic moment per unit area of the ferromagnetic layer (Ms × t; the product of the saturation magnetic flux density and the film thickness) is calculated as the magnitude of the magnetic moment per unit area of the free magnetic layer (Ms Xt; product of saturation magnetic flux density and film thickness).

Specifically, the ratio of the magnitude of the magnetic moment per unit area of the free magnetic layer (Ms × t) to the magnitude of the magnetic moment per unit area of the ferromagnetic layer (Ms × t) is It is preferably in the range of 3 or more and 20 or less.

The side of the ferromagnetic layer in contact with the non-magnetic layer is a NiFe (permalloy) layer or NiFeX.
(X is Al, Si, Ti, V, Cr, Mn, Cu, Z
r, Nb, Mo, Ru, Rh, Hf, Ta, W, Ir,
By forming it with one or more elements selected from Pt), the magnitude of the interlayer coupling magnetic field between the free magnetic layer and the ferromagnetic layer can be appropriately reduced, and the first layer of the ferromagnetic layer can be formed. 2 By forming the side in contact with the antiferromagnetic layer with a ferromagnetic material containing Co (cobalt), the second
The exchange coupling magnetic field between the antiferromagnetic layer and the ferromagnetic layer can be increased.

Alternatively, in the present invention, the ferromagnetic layer is made of N.
By forming a single layer structure of iFe (permalloy) and forming the ferromagnetic layer to have a film thickness of more than 0 nm and 3 nm or less, the free magnetic layer is made into a single magnetic domain and its magnetization direction is the magnetization of the pinned magnetic layer. The magnetization direction of the free magnetic layer can be reliably changed in the direction orthogonal to the direction, and the leakage magnetic field can change the magnetization direction.

The ferromagnetic layer may have a single layer structure made of CoFeCr or CoFe.

In the free magnetic layer, a NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti, V, C) is provided at least on the side in contact with the nonmagnetic layer.
r, Mn, Cu, Zr, Nb, Mo, Ru, Rh, H
It is preferable that there is a magnetic region composed of one or more elements selected from f, Ta, W, Ir and Pt. Thereby, the magnitude of the interlayer coupling magnetic field between the free magnetic layer and the ferromagnetic layer can be appropriately reduced.

It is preferable that the free magnetic layer has a magnetic region made of a ferromagnetic material containing Co (cobalt) on the side in contact with the nonmagnetic material layer. This can prevent diffusion of the material (Ni or the like) of the free magnetic layer into the non-magnetic material layer in contact with the free magnetic layer, and prevent a decrease in magnetoresistance change rate.

Further, the ferromagnetic material containing Co means Co
It is preferably Fe or CoFeCr.

With the magnetic sensing element having the structure of the present invention, the reproduction efficiency η (%) can be set to 10% or more and 50% or less. The regeneration efficiency η is η =
It is defined as {(maximum resistance change amount of magnetic detection element due to leakage magnetic field from recording medium) / (theoretical value of maximum resistance change amount of magnetic detection element)} × 100. The theoretical value of the maximum resistance change amount of the magnetic detection element is the resistance value when the magnetization directions of the free magnetic layer and the pinned magnetic layer are antiparallel and the magnetization direction of the free magnetic layer and the pinned magnetic layer is in the parallel state. It is the difference in the resistance value when.

In the magnetic sensing element of the present invention, when an external magnetic field is applied, the magnetization direction of the track width region of the free magnetic layer is inclined by 12 ° or more with respect to the magnetization direction when no external magnetic field is applied. You can

In the present invention, the multilayer film is arranged from the bottom in order from the first antiferromagnetic layer, the pinned magnetic layer, the nonmagnetic material layer, the free magnetic layer, the nonmagnetic layer, the ferromagnetic layer, and the first layer. The two antiferromagnetic layers may be stacked in this order.

Alternatively, from the bottom of the multilayer film, the second antiferromagnetic layer, the ferromagnetic layer, the nonmagnetic layer, the free magnetic layer, the nonmagnetic material layer, the pinned magnetic layer and the first layer.
The antiferromagnetic layers may be laminated in this order.

In the free magnetic layer according to the present invention, only a part of the free magnetic layer in the film thickness direction has a track width dimension of the track width dimension, and the remaining part has a track width dimension larger than the track width dimension. It may have dimensions.

If a part of the free magnetic layer has a dimension in the track width direction larger than the track width dimension,
It is possible to reduce the demagnetizing field inside the free magnetic layer due to the surface magnetic charges generated at both ends of the free magnetic layer,
Disturbance of the magnetization direction inside the free magnetic layer can be reduced.

In particular, the magnetic detection element is a CPP (Current) to which a current is supplied in a direction perpendicular to the film surface of the multilayer film.
Perpendicular to the Pla
ne) type, and when the non-magnetic material layer, the pinned magnetic layer and the first antiferromagnetic layer are a top type magnetic detection element on the upper layer of the free magnetic layer, a part of the free magnetic layer is a track. It is easy to form so as to have a dimension in the track width direction larger than the width dimension.

Further, in the free magnetic layer, a plurality of ferromagnetic material layers having different magnetic moments per unit area are laminated with a nonmagnetic intermediate layer interposed therebetween and adjacent to each other with the nonmagnetic intermediate layer interposed. In the ferrimagnetic state in which the magnetization directions of the ferromagnetic material layer are anti-parallel, the magnetic moment per unit area of the free magnetic layer can be made thin, and the magnetization direction of the free magnetic layer can be outside of the magnetization direction. The rate of change with respect to the magnetic field can be improved. That is, the magnetic field detection sensitivity of the magnetic detection element is improved, which is preferable. Also,
It is also possible to reduce the demagnetizing field inside the free magnetic layer.

The non-magnetic intermediate layer is made of, for example, Ru, R
It is preferably formed of an alloy of one or more of h, Ir, Cr, Re and Cu.

In the present invention, it is preferable that at least one of the plurality of ferromagnetic material layers is made of a magnetic material having the following composition.

The composition formula is represented by CoFeNi, the composition ratio of Fe is 9 atomic% or more and 17 atomic% or less, the composition ratio of Ni is 0.5 atomic% or more and 10 atomic% or less, and the remaining composition ratio is C
a magnetic material that is o.

Further, it is preferable to form an intermediate layer made of a CoFe alloy or Co between the ferromagnetic material layer and the nonmagnetic material layer which are laminated at the position closest to the nonmagnetic material layer. When forming the intermediate layer, it is preferable that at least one of the plurality of ferromagnetic material layers is formed of a magnetic material having the following composition.

The composition formula is represented by CoFeNi, the composition ratio of Fe is 7 atomic% or more and 15 atomic% or less, the composition ratio of Ni is 5 atomic% or more and 15 atomic% or less, and the remaining composition ratio is Co. material.

Further, in the present invention, it is preferable that all layers of the plurality of ferromagnetic material layers are formed of the CoFeNi.

In the free magnetic layer, a plurality of ferromagnetic material layers having different magnetic moments per unit area are laminated with a nonmagnetic intermediate layer interposed therebetween, and the ferromagnetic materials adjacent to each other with the nonmagnetic intermediate layer interposed therebetween. In the artificial ferrimagnetic state in which the magnetization directions of the material layers are antiparallel, in order to appropriately maintain this antiparallel magnetization state, the material of the free magnetic layer is improved so that RKKY works between the plurality of ferromagnetic material layers. There is a need to increase the exchange coupling magnetic field in the interaction.

A NiFe alloy is often used as a magnetic material for forming the ferromagnetic material layer. NiFe
The alloy has been conventionally used for a free magnetic layer or the like because of its excellent soft magnetic characteristics. However, when the free magnetic layer has a laminated ferri structure, the antiparallel coupling force between the ferromagnetic material layers formed of the NiFe alloy is not so great. Not strong.

Therefore, in the present invention, in order to improve the material of the ferromagnetic material layer and enhance the antiparallel coupling force between the plurality of ferromagnetic material layers, at least one of the plurality of ferromagnetic material layers, preferably It was decided to use CoFeNi alloy for all layers. By containing Co, the above antiparallel coupling force can be strengthened.

As a result, the exchange coupling magnetic field in the RKKY interaction generated between the plurality of ferromagnetic material layers can be strengthened. Specifically, the magnetic field when the antiparallel state collapses, that is, the spin-flop magnetic field (Hsf) can be increased to about 293 (kA / m).

Within the above composition range, the magnetostriction of the plurality of ferromagnetic material layers is -3 × 10 ^-6 to 3 × 10.
It can be set within the range of ^-6 and has a coercive force of 790.
It can be reduced to (A / m) or less.

According to the present invention, the upper electrode layer is electrically connected to the upper surface of the multilayer film, and the lower electrode layer is electrically connected to the lower surface of the multilayer film, in a direction perpendicular to the film surface of the multilayer film. CPP (Current Perp)
It is effective to apply it to an endless to the plane) type magnetic detection element.

In the CPP type magnetic sensing element, if the multilayer film has a semi-metallic ferromagnetic Heusler alloy layer, the ratio of up-spin electrons and down-spin electrons flowing in the multilayer film can be controlled, and the magnetoresistance change. It is preferable because the rate can be improved.

Further, when the semi-metallic ferromagnetic Heusler alloy layer is a part of the free magnetic layer and the NiFe layer having high soft magnetic characteristics is in contact with the semi-metallic ferromagnetic Heusler alloy layer, the change in magnetic resistance occurs. It is preferable because the rate can be improved.

In the present invention, the first antiferromagnetic layer and the second antiferromagnetic layer can be formed of antiferromagnetic materials having the same composition.

The first antiferromagnetic layer and / or the second antiferromagnetic layer are made of PtMn alloy or X--Mn.
(However, X is Pd, Ir, Rh, Ru, Os, Ni,
An alloy of any one or more of Fe) or Pt—Mn—X ′ (where X ′ is Pd,
Ir, Rh, Ru, Au, Ag, Os, Cr, Ni, A
It is preferable to use an alloy of any one of r, Ne, Xe, and Kr or two or more elements.

Further, in the present invention, in the multilayer film, the ferromagnetic layer and the second antiferromagnetic layer are laminated on the upper side or the lower side of the free magnetic layer via the nonmagnetic layer, and at least the free magnetic layer. Has a structure in which a pinned magnetic layer is formed on both end faces in the track width direction with a non-magnetic material layer interposed therebetween, and the one antiferromagnetic layer is laminated on the pinned magnetic layer. It may be a magnetic detection element having an electrode layer formed on.

In the present invention, the free magnetic layer and the pinned magnetic layer are arranged side by side in the track width direction, and the current from the electrode layer passes through the pinned magnetic layer from the track width direction to the free magnetic layer, or the free magnetic layer. The flow direction is such that the current flows through the pinned magnetic layer.

In the magnetic detecting element having the above-described structure, the resistance change amount (ΔR) can be increased, the reproduction output can be improved more effectively, and the resistance change rate can be improved by narrowing the track width. Even if the free magnetic layer and the pinned magnetic layer are arranged side by side in the track width direction, a ferromagnetic layer and a second antiferromagnetic layer can be formed above or below the free magnetic layer with a nonmagnetic layer interposed therebetween. By laminating, the magnetization control of the free magnetic layer can be optimized.

The method of manufacturing the magnetic sensing element of the present invention is characterized by including the following steps. (A) A second antiferromagnetic layer, a ferromagnetic layer, a nonmagnetic layer, a free magnetic layer, a nonmagnetic material layer, a fixed magnetic layer, an intermediate antiferromagnetic layer, and a nonmagnetic protective layer are stacked in this order from the bottom on the substrate. And the process of
(B) performing annealing in a first magnetic field to generate an exchange coupling magnetic field between the second antiferromagnetic layer and the ferromagnetic layer, and fixing the magnetization of the ferromagnetic layer in the track width direction;
(C) removing all or part of the non-magnetic protective layer,
(D) An upper antiferromagnetic layer is formed on the nonmagnetic protective layer or the intermediate antiferromagnetic layer, and a first antiferromagnetic layer having the intermediate antiferromagnetic layer and the upper antiferromagnetic layer is formed. Process,
(E) A direction in which the second magnetic field anneal is performed to generate an exchange coupling magnetic field between the first antiferromagnetic layer and the pinned magnetic layer, and the magnetization of the pinned magnetic layer intersects the magnetization direction of the ferromagnetic layer. Step of fixing to.

In the present invention, in the step (a), the second antiferromagnetic layer to the nonmagnetic protective layer are continuously formed on the substrate.

In the present invention, the nonmagnetic protective layer is made of a noble metal or the like that is difficult to oxidize, and does not increase in film thickness due to oxidation unlike the Ta film which has been conventionally used as the nonmagnetic protective layer.

Therefore, even if the nonmagnetic protective layer is thinly formed, a sufficient antioxidation effect can be obtained, so that the nonmagnetic protective layer can be removed by low energy ion milling. The intermediate antiferromagnetic layer formed under the magnetic protection layer can be appropriately protected from damage due to the ion milling.

Further, even if the noble metal element or the like diffuses inside the intermediate antiferromagnetic layer and the upper antiferromagnetic layer by annealing or the like, the properties of the antiferromagnetic layer do not deteriorate. The Ta film used conventionally is not preferable because it tends to deteriorate the property (function) of the antiferromagnetic layer when it diffuses into the antiferromagnetic layer as compared with Ru or the like.

In the present invention, the nonmagnetic protective layer is made of Ru,
Re, Pd, Os, Ir, Pt, Au, Rh, Cu, C
It is preferable to form any one or more of r.

In the step (a), if the intermediate antiferromagnetic layer is formed with a thickness of 10 Å or more and 50 Å or less, or more preferably 30 Å or more and 40 Å or less, (b)
By the first magnetic field annealing in the step, an exchange coupling magnetic field is not generated between the intermediate antiferromagnetic layer and the pinned magnetic layer, and the magnetization direction of the pinned magnetic layer faces the same direction as the magnetization direction of the free magnetic layer. You can avoid that.

In the present invention, it has been described above that even if the nonmagnetic protective layer is formed thin, a sufficient antioxidation effect can be obtained. Specifically, in the step (a), The nonmagnetic protective layer can be formed with a thickness of 3 Å or more and 10 Å or less.

In the step (c), it is preferable that the nonmagnetic protective layer be ground or the nonmagnetic protective layer be entirely removed until the thickness of the nonmagnetic protective layer becomes 3 Å or less. .

When the non-magnetic protective layer is completely removed in the step (c), the first antiferromagnetic layer is composed of only the intermediate antiferromagnetic layer and the upper antiferromagnetic layer. However, if all of the nonmagnetic protective layer is removed, the surface of the intermediate antiferromagnetic layer may be damaged by ion milling and antiferromagnetism may be reduced.

In the present invention, as long as the non-magnetic protective layer remains 3Å or less, the non-magnetic protective layer may remain between the intermediate antiferromagnetic layer and the upper antiferromagnetic layer. The intermediate antiferromagnetic layer, the nonmagnetic protective layer, and the upper antiferromagnetic layer may function as a first antiferromagnetic layer as a unit.

[0080]

FIG. 1 is a partial cross-sectional view of a magnetic detection element according to a first embodiment of the present invention as seen from the side facing a recording medium.

The magnetic detecting element shown in FIG. 1 is a GMR head for reproducing an external signal recorded on a recording medium. The surface facing the recording medium is, for example, a plane perpendicular to the film surface of the thin film forming the magnetic detection element and parallel to the magnetization direction when the external magnetic field of the free magnetic layer of the magnetic detection element is not applied. In FIG. 1, the surface facing the recording medium is X-Z.
It is a plane parallel to the plane.

When the magnetic detecting element is used in a floating magnetic head, the surface facing the recording medium is the so-called ABS surface.

The magnetic detecting element is formed on the trailing end surface of the slider made of, for example, alumina-titanium carbide (Al ₂ O ₃ -TiC). The slider is joined to an elastically deformable support member made of stainless steel or the like on the side opposite to the surface facing the recording medium to form a magnetic head device.

The track width direction is the width direction of the region in which the magnetization direction is changed by the external magnetic field. For example, the magnetization direction when the external magnetic field of the free magnetic layer is not applied, that is, the X direction in the figure. Is.

The recording medium faces the surface of the magnetic detecting element facing the recording medium, and moves in the Z direction in the figure. The direction of the leakage magnetic field from this recording medium is the Y direction in the figure.

In FIG. 1, the lower shield layer 20 which also serves as the lower electrode layer is formed on the trailing end surface of the slider via an alumina layer (not shown).
0, underlayer 21, seed layer 22, second antiferromagnetic layer 2
3, a ferromagnetic layer 24 composed of the first ferromagnetic layer 24a and the second ferromagnetic layer 24b, a non-magnetic layer 25, a free magnetic layer 26 composed of the first magnetic layer 26a and the second magnetic layer 26b, and a non-magnetic material layer 27. , Second pinned magnetic layer 28a, non-magnetic intermediate layer 28
b, a synthetic ferripinned pinned magnetic layer 28 including the first pinned magnetic layer 28c, a first antiferromagnetic layer 29, and a protective layer 30 are laminated in this order from the bottom to form a multilayer film A.

From the protective layer 30 of the multilayer film A to the free magnetic layer 2
6 has a track width dimension Tw up to a part in the film thickness direction of the first magnetic layer 26a, and the ferromagnetic layer 24 and the second antiferromagnetic layer 23 from the remaining portion of the first magnetic layer 26a. The dimension of the seed layer 22 and the underlying layer 21 in the track width direction is larger than the track width dimension Tw.

Insulating layers 32, 32 are formed on both sides in the track width direction from the protective layer 30 to the middle of the first magnetic layer 26a of the free magnetic layer 26, and the insulating layers 32, 3 are formed.
2 and the protective layer 30 of the multilayer film A, an upper shield layer 31 which also serves as an upper electrode layer is formed.

From the lower shield layer 20 to the upper shield layer 3
The elements up to 1 are the magnetic detection elements according to the first embodiment of the present invention.

In FIG. 1, the lower shield layer 20 also serves as the lower electrode layer and the upper shield layer 31 also serves as the upper electrode layer. However, the lower shield layer and the lower electrode layer and the upper shield layer and the upper electrode layer are Different layers may be formed of different materials.

The magnetic sensing element shown in FIG. 1 is a so-called top type spin valve type magnetic sensing element.

Lower shield layer 20, underlayer 21, seed layer 22, second antiferromagnetic layer 23, ferromagnetic layer 24, nonmagnetic layer 25, free magnetic layer 26, nonmagnetic material layer 27, pinned magnetic layer 28, First antiferromagnetic layer 29, protective layer 30, insulating layer 3
2 and the upper shield layer 31 are formed by a thin film forming process such as a sputtering method or a vapor deposition method.

As the sputtering method, for example, magnetron sputtering, RF 2-pole sputtering, RF 3-pole sputtering, ion beam sputtering, opposed target type sputtering or the like can be used. Further, in the present invention, in addition to the sputtering method and the vapor deposition method, MBE (Molecular-Beam-Epitaxy) is used.
A film forming process such as a CVD method or an ICB (ion-cluster-beam) method can be used.

As shown in FIG. 1, the multi-layered film A composed of the above-mentioned base layer 21 to protective layer 30 is the protective layer 30.
From both ends to the part of the first magnetic layer 26a of the free magnetic layer 26 in the track width direction (X direction in the drawing),
Aa is a continuous surface perpendicular to the surface Ab of the multilayer film A. However, as shown by the dotted lines Aa1 and Aa1 in FIG. 1, both end surfaces in the track width direction from the protective layer 30 to a part of the first magnetic layer 26a of the free magnetic layer 26 are inclined with respect to the surface Ab of the multilayer film A. Surface Aa1, Aa1
May be

Incidentally, the optical track of the magnetic detection element of FIG.
The width Tw is determined by the dimension of the nonmagnetic material layer 27 in the track width direction.
Can be In the magnetic detection element of the present embodiment, the optical
Width Tw of 0.1 μm or less, especially 0.06 μm or less
And then 200 Gbit / in ^TwoCompatible with the above recording densities
You can

The magnetic sensing element shown in FIG. 1 is a so-called spin valve type magnetic sensing element, in which the magnetization direction of the pinned magnetic layer 28 is properly pinned in the direction parallel to the Y direction in the drawing, and the free magnetic layer is used. The magnetization of 26 is properly aligned in the X direction in the figure, and the fixed magnetic layer 28 and the free magnetic layer 26 are
Are in an orthogonal relationship. The leakage magnetic field from the recording medium penetrates in the Y direction of the magnetic detection element in the drawing, and the magnetization of the free magnetic layer 26 fluctuates with high sensitivity. The resistance changes,
The leakage magnetic field from the recording medium is detected by the voltage change based on the change of the electric resistance value.

However, it is the relative angle between the magnetization direction of the second pinned magnetic layer 28a and the magnetization direction of the free magnetic layer 26 that directly contributes to the change (output) of the electric resistance value, and these relative angles are the detected currents. It is preferable that they are orthogonal to each other in a state where they are energized and a signal magnetic field is not applied.

The recording medium facing the surface of the magnetic detection element facing the recording medium moves in the Z direction in the figure.

The protective layer 30 is made of a conductive material such as Ta and has a film thickness of 30Å in the present embodiment.

Lower shield layer 20 and upper shield layer 3
1 is formed using a magnetic material such as NiFe. It is preferable that the lower shield layer 20 and the upper shield layer 31 have easy axes of magnetization oriented in the track width direction (X direction in the drawing). The lower shield layer 20 and the upper shield layer 31 may be formed by an electrolytic plating method.

The underlayer 21 is made of Ta, Hf, Nb, Zr,
It is preferably formed of at least one of Ti, Mo and W. The underlayer is formed with a film thickness of about 50 Å or less. The base layer may not be formed.
In the present embodiment, the thickness of the underlayer 21 is 30Å.

The seed layer 22 is made of NiFe, NiFeCr.
It is formed using Cr or Cr. In the present embodiment, the seed layer 22 has a film thickness of 50Å.

Since the magnetic sensing element in this embodiment is of the CPP type in which the sense current flows in the direction perpendicular to the film surface of each layer, it is necessary to appropriately flow the sense current also in the seed layer. Therefore, it is preferable that the seed layer is not a material having a high specific resistance. That is, in the CPP type, the seed layer is preferably formed of a material having a low specific resistance such as NiFe alloy or Cr. The seed layer may not be formed.

The second antiferromagnetic layer 23 and the first antiferromagnetic layer 2
9 is a PtMn alloy or X-Mn (where X is
Pd, Ir, Rh, Ru, Os, Ni, Fe, which is one or more elements) alloy, or P
t-Mn-X '(where X'is Pd, Ir, Rh, R
u, Au, Ag, Os, Cr, Ni, Ar, Ne, X
e, Kr, which is one or two or more elements).

In this embodiment, the first antiferromagnetic layer 29 and the second antiferromagnetic layer 23 can be formed using antiferromagnetic materials having the same composition.

Immediately after the film formation, these alloys have a disordered face-centered cubic structure (fcc), but undergo a structural transformation to a CuAuI type ordered face-centered tetragonal structure (fct) by heat treatment.

The thickness of the second antiferromagnetic layer 23 is 80Å to 30.
It is 0Å, for example 150Å. Here, in the PtMn alloy and the alloy represented by the formula X-Mn for forming the antiferromagnetic layer, Pt or X is 37 to 63.
It is preferably in the range of at%. Also, the PtM
In the n alloy and the alloy represented by the formula of X-Mn,
More preferably, Pt or X is in the range of 47 to 57 at%. Unless otherwise specified, the upper and lower limits of the numerical range indicated by are as follows.

In the alloy represented by the formula Pt-Mn-X ', it is preferable that X' + Pt is in the range of 37 to 63 at%. Further, in the alloy represented by the formula of Pt—Mn—X ′, X ′ + Pt is 47 to 57 at%.
The range is more preferably. Further, the Pt-
In the alloy represented by the formula of Mn-X ', X'is 0.2.
It is preferably in the range of 10 at%. However,
When X ′ is any one or more of Pd, Ir, Rh, Ru, Os, Ni and Fe, X ′
Is preferably in the range of 0.2 to 40 at%.

By using these alloys and heat-treating them, an antiferromagnetic layer which generates a large exchange coupling magnetic field can be obtained. In particular, if it is a PtMn alloy, 4
An excellent second antiferromagnetic layer 23 and first antiferromagnetic layer 29 having an exchange coupling magnetic field of 8 kA / m or more, for example, 64 kA / m or more, and a blocking temperature for losing the exchange coupling magnetic field of 380 ° C. are extremely high. Obtainable.

When the magnetic sensing element of FIG. 1 is formed using the method for manufacturing a magnetic sensing element of this embodiment described later, the first antiferromagnetic layer 29 has a film thickness of 10 Å or more and 50 Å or less. It has a multilayer structure including an intermediate antiferromagnetic layer 29a, a nonmagnetic protective layer 29b made of a noble metal or the like having a film thickness of 1 Å or more and 3 Å or less, and an upper antiferromagnetic layer 29c.

Intermediate antiferromagnetic layer 29a and upper antiferromagnetic layer 2
9c is an antiferromagnetic material having the same composition, specifically P mentioned above.
tMn alloy, X-Mn alloy, or Pt-Mn-
It is formed using an X'alloy.

The total thickness of the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c is 80 Å or more and 50 or more.
It is less than 0Å. For example, 150Å. Since the intermediate antiferromagnetic layer 29a has a thin film thickness of 10 Å or more and 50 Å or less,
It does not exhibit antiferromagnetism by itself, but exhibits antiferromagnetism only when the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c are integrated, and an exchange coupling magnetic field is generated between the pinned magnetic layer 28 and the pinned magnetic layer 28. Let

The nonmagnetic protective layer 29b has a thickness of 1 Å or more and 3 Å
The following thin film thicknesses, Ru, Re, Pd, Os, I
Since it is formed of one or more of r, Pt, Au, Rh, Cu, and Cr, the intermediate antiferromagnetic layer 29.
a and the upper antiferromagnetic layer 29c to cause an antiferromagnetic interaction, and the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c
Can be made to function as an integrated antiferromagnetic layer. Further, even if the material of the nonmagnetic protective layer 29b diffuses into the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c, the antiferromagnetic property does not deteriorate.

The nonmagnetic protective layer 29b may not be present, and the first antiferromagnetic layer 29 may be composed of the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c. Further, the first antiferromagnetic layer 29 may be a single antiferromagnetic layer.

The first pinned magnetic layer 28c and the second pinned magnetic layer 28a are made of a ferromagnetic material, for example, NiFe alloy, Co, CoFeNi alloy, CoFe alloy, CoNi alloy or the like. In particular, it is preferably formed of CoFe alloy or Co. The first pinned magnetic layer 28c and the second pinned magnetic layer 28a are preferably made of the same material.

The non-magnetic intermediate layer 28b is made of a non-magnetic material and is made of Ru, Rh, Ir, Cr, R.
e, Cu, or one or more of these alloys. It is particularly preferably formed of Ru.

The first pinned magnetic layer 28c and the second pinned magnetic layer 28a are each formed to have a thickness of about 10 to 70Å. For example, the film thickness of the first pinned magnetic layer 28c is 30Å, and the film thickness of the second pinned magnetic layer 28a is 40Å. The thickness of the nonmagnetic intermediate layer is about 3Å to 10Å, for example, 8Å.

In FIG. 1, the first pinned magnetic layer 28c and the second pinned magnetic layer 28a, which have different magnetic moments per unit area (Ms × t; product of saturation magnetic flux density and film thickness), form the non-magnetic intermediate layer 28b. What is laminated via the above functions as one fixed magnetic layer.

The first pinned magnetic layer 28c is the first antiferromagnetic layer 2
9 and is annealed in a magnetic field, an exchange anisotropic magnetic field (exchange coupling magnetic field) due to exchange coupling is generated at the interface between the first pinned magnetic layer 28c and the first antiferromagnetic layer 29. And the magnetization direction of the first pinned magnetic layer 28c is Y in the figure.
Fixed in the direction. When the magnetization direction of the first pinned magnetic layer 28c is pinned in the Y direction in the figure, the magnetization direction of the second pinned magnetic layer 28a that faces the non-magnetic intermediate layer 28b is the same as the magnetization direction of the first pinned magnetic layer 28c. It is fixed in the antiparallel state.

Thus, the first pinned magnetic layer 28c and the second pinned magnetic layer 28c
When the pinned magnetic layer 28a is in a ferrimagnetic state in which the magnetization directions are antiparallel, the first pinned magnetic layer 28c and the second pinned magnetic layer 28a fix the other magnetizing direction to each other, and as a whole, The magnetization direction of the pinned magnetic layer can be strongly fixed in a fixed direction.

The magnetic moment per unit area (Ms × t) of the first pinned magnetic layer 28c and the second pinned magnetic layer 28c.
Magnetic moment per unit area (Ms × t)
The direction of t) is the magnetization direction of the pinned magnetic layer.

In FIG. 1, the first pinned magnetic layer 28c and the second pinned magnetic layer 28c
The fixed magnetic layer 28a is formed using the same material, and further,
By making each film thickness different, each magnetic moment (Ms × t) per unit area is made different.

Also, the demagnetizing field (dipole magnetic field) due to the fixed magnetization of the first pinned magnetic layer 28c and the second pinned magnetic layer 28a.
Can be canceled by the static magnetic field couplings of the first pinned magnetic layer 28c and the second pinned magnetic layer 28a canceling each other. Thereby, the contribution of the demagnetizing field (dipole magnetic field) due to the fixed magnetization of the fixed magnetic layer 28 to the variable magnetization of the free magnetic layer 26 can be reduced.

Therefore, it becomes easier to correct the direction of the variable magnetization of the free magnetic layer 26 to a desired direction, and it is possible to obtain a spin valve type magnetic sensing element having a small asymmetry and excellent symmetry.

Here, the asymmetry indicates the degree of asymmetry of the reproduction output waveform, and when the reproduction output waveform is given, the asymmetry becomes small if the waveform is symmetrical. Therefore, as the asymmetry approaches 0, the reproduced output waveform has better symmetry.

The asymmetry is based on the free magnetic layer 26.
Is 0 when the direction of the magnetization of 1 and the direction of the fixed magnetization of the fixed magnetic layer 28 are orthogonal to each other. If the asymmetry is greatly deviated, the information cannot be read accurately from the medium, which causes an error. Therefore, the smaller the asymmetry, the higher the reliability of the reproduction signal processing, and the more excellent the spin valve type magnetic detection element becomes.

Further, the demagnetizing field (dipole magnetic field) Hd due to the fixed magnetization of the fixed magnetic layer 28 has a non-uniform distribution in the element height direction of the free magnetic layer 26, being large at the ends and small at the center. Although the formation of a single magnetic domain in the free magnetic layer 26 may be hindered, the dipole magnetic field Hd can be reduced by forming the pinned magnetic layer 28 to have the above-mentioned laminated structure, which allows the domain wall in the free magnetic layer to be reduced. It is possible to prevent the occurrence of non-uniform magnetization and Barkhausen noise.

The pinned magnetic layer 28 has a one-layer structure using any of the above magnetic materials or a two-layer structure including a layer formed of any of the above magnetic materials and a diffusion preventing layer such as a Co layer. Is also good.

The non-magnetic material layer 27 is a layer for preventing magnetic coupling between the fixed magnetic layer 28 and the free magnetic layer 26,
It is preferably formed of a non-magnetic material having conductivity such as Cu, Cr, Au, Ag. Particularly, Cu is preferable. The nonmagnetic material layer 27 is, for example, 1
It is formed with a film thickness of about 8 to 30 Å. In the present embodiment, the film thickness of the nonmagnetic material layer 27 is 30Å.

The nonmagnetic material layer 27 is made of Al ₂ O ₃ or S.
Although it may be formed of an insulating material such as iO ₂ , in the case of the CPP type magnetic detection element as in the present embodiment,
Since the sense current must flow in the non-magnetic material layer 27 in the direction perpendicular to the film surface, when the non-magnetic material layer 27 is an insulator, the thickness of the non-magnetic material layer 27 is 50Å or less. It is necessary to make it thin so that the tunnel current can flow. The non-magnetic material layer 27 is made of Al ₂
When formed of a material that partially contains an insulating material such as O ₃ , TaO ₂ or Cu—Al ₂ O ₃ composite film, the nonmagnetic material layer 27 functions as a current limiting layer that reduces the effective element area. You can also let it.

In the magnetic sensing element shown in FIG. 1, the free magnetic layer 26 includes the first magnetic layer 26a and the second magnetic layer 26b.
Is a two-layer structure.

The first magnetic layer 26 on the side in contact with the nonmagnetic layer 25
a is a NiFe (permalloy) layer or NiFeX
(X is Al, Si, Ti, V, Cr, Mn, Cu, Z
r, Nb, Mo, Ru, Rh, Hf, Ta, W, Ir,
One or more elements selected from Pt),
The second magnetic layer 26b on the side in contact with the non-magnetic material layer 27 is C
This is a layer made of a ferromagnetic material containing Co (cobalt) such as o, CoFe, and CoFeNi. In the present embodiment, the film thickness of the first magnetic layer 26a is 100Å and the second magnetic layer 2
The film thickness of 6b is 20Å. CoFe and CoFeCr are preferably selected as the ferromagnetic material containing Co.

The second magnetic layer 26b of the free magnetic layer 26 is C
By forming a layer made of a ferromagnetic material containing o (cobalt), it is possible to prevent the material (Ni or the like) of the free magnetic layer 26 from diffusing into the non-magnetic material layer 27 and prevent a decrease in the magnetoresistance change rate. You can

The interface between the first magnetic layer 26a and the second magnetic layer 26b forming the free magnetic layer 26 may not be clearly seen as shown in the drawing. For example, there is a case where the first magnetic layer 26a and the second magnetic layer 26b cause thermal diffusion. In such a case, the boundary surface becomes unclear. Therefore, when the boundary surface between the first magnetic layer 26a and the second magnetic layer 26b cannot be clearly seen as in the embodiment shown in FIG. 1, the free magnetic layer 26 has at least the side in contact with the non-magnetic layer 25. It suffices that there is a magnetic region made of NiFe or NiFeX, while a magnetic region made of a ferromagnetic material layer containing Co is present on the side in contact with the nonmagnetic material layer 27.

In this embodiment, the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are stacked below the track width region 26c of the free magnetic layer 26 with the nonmagnetic layer 25 interposed therebetween.

The nonmagnetic layer 25 is made of Ru, Rh, Ir, C.
It is formed of an alloy of one or more of r, Re and Cu. In the present embodiment, the film thickness of the nonmagnetic layer 25 is 8Å.

The ferromagnetic layer 24 has a two-layer structure of a first ferromagnetic layer 24a and a second ferromagnetic layer 24b. In the present embodiment, for example, the film thickness of the first ferromagnetic layer 24a is 8Å, and the film thickness of the second ferromagnetic layer 24b is 6Å.

In FIG. 1, the second ferromagnetic layer 24b, which is the side of the ferromagnetic layer 24 in contact with the nonmagnetic layer 25, is a NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ru, R
h, Hf, Ta, W, Ir, Pt, and one or more elements).

The first ferromagnetic layer 24a, which is in contact with the second antiferromagnetic layer 23, is made of a ferromagnetic material containing Co (cobalt) such as Co or CoFe. By forming the first ferromagnetic layer 24a with a ferromagnetic material containing Co (cobalt), the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 can be increased. CoFe and CoFeCr are preferably selected as the ferromagnetic material containing Co.

In the ferromagnetic layer 24 as well as the free magnetic layer 26, the ferromagnetic layer 24 has a magnetic region of NiFe or NiFeX at least on the side in contact with the non-magnetic layer 25. 2 A magnetic region made of a ferromagnetic material layer containing Co may be present on the side in contact with the antiferromagnetic layer 23.

Alternatively, the ferromagnetic layer 24 may have a single-layer structure made of NiFe (permalloy) having a film thickness of more than 0 nm and 3 nm or less.

Alternatively, the ferromagnetic layer 24 is made of CoFe
You may form by the single layer structure which consists of Cr or CoFe.

In any of the single layer structures described above, good reproduction characteristics can be obtained according to the experimental results described later.

In the magnetic sensing element shown in FIG. 1, the magnetization direction of the ferromagnetic layer 24 is oriented in the direction crossing the magnetization direction of the pinned magnetic layer 28 by the exchange coupling magnetic field with the second antiferromagnetic layer 23. .

Further, since the free magnetic layer 26, which is a ferromagnetic material layer made of a ferromagnetic material, is laminated on the ferromagnetic layer 24 via the non-magnetic layer 25, the free magnetic layer 26 becomes the ferromagnetic layer 24. The inter-layer coupling magnetic field through the non-magnetic layer 25, in this case, is made into a single magnetic domain by the RKKY interaction, and the magnetization direction is directed to the direction crossing the magnetization direction of the pinned magnetic layer 28.

Thus, the ferromagnetic layer 24 and the non-magnetic layer 2
When the free magnetic layer 26 is made into a single domain and the magnetization direction is controlled by the interlayer coupling magnetic field via the free magnetic layer 2, the free magnetic layer 2 is exposed by an external magnetic field such as a leakage magnetic field from the recording medium.
It is possible to suppress the disturbance of the longitudinal bias magnetic field applied to 6 and the disturbance of the magnetic domain structure of the free magnetic layer 26.

Further, in the ferromagnetic layer 24, a plurality of ferromagnetic material layers having different magnetic moments per unit area are laminated with a non-magnetic intermediate layer interposed therebetween and adjacent to each other with the non-magnetic intermediate layer interposed therebetween. It may be in a ferrimagnetic state in which the magnetization directions of the ferromagnetic material layers are antiparallel. by this,
The magnetization direction of the ferromagnetic layer 24 can be firmly fixed in one direction.

The nonmagnetic layer 25 is formed of Ru, and the magnetization directions of the free magnetic layer 26 and the ferromagnetic layer 24 are set to 18
When changing to an artificial ferri state that is different by 0 °, Ru
It is preferable that the film thickness is 8Å to 11Å or 15Å to 21Å.

In the present invention, the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 is increased to make the magnetization direction of the ferromagnetic layer 24 strong in the direction crossing the magnetization direction of the pinned magnetic layer 28. After being fixed, the magnitude of the interlayer coupling magnetic field between the free magnetic layer 26 and the ferromagnetic layer 24 is made smaller than the exchange coupling magnetic field, whereby the free magnetic layer 26 is made into a single magnetic domain and the magnetization direction is fixed. It is necessary to make sure that the magnetization direction of the free magnetic layer 26 can be changed in a direction orthogonal to the magnetization direction of the magnetic field, and that the magnetization direction of the free magnetic layer 26 can be changed by the leakage magnetic field.

The exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 is increased to increase the free magnetic layer 26 and the ferromagnetic layer 2.
In order to make the magnitude of the inter-layer coupling magnetic field between the four magnetic fields smaller than the exchange coupling magnetic field, the magnitude of the magnetic moment per unit area of the ferromagnetic layer 24 (Ms × t; saturation magnetic flux density and film) The product of thicknesses is smaller than the magnitude of the magnetic moment per unit area of the free magnetic layer 26 (Ms × t; product of saturation magnetic flux density and film thickness).

The magnitude of the magnetic moment per unit area of the ferromagnetic layer 24 (Ms × t; product of saturation magnetic flux density and film thickness) is the magnitude of the magnetic moment per unit area of the first ferromagnetic layer 24a. (Ms × t) and the second ferromagnetic layer 24b
Of magnetic moment per unit area of (Ms ×
It is the sum of t). The magnitude of the magnetic moment per unit area of the free magnetic layer 26 (Ms × t; product of saturation magnetic flux density and film thickness) is the magnitude of the magnetic moment per unit area of the first magnetic layer 26a (Ms × t). t) and the second magnetic layer 2
The magnitude of the magnetic moment per unit area of 6b (Ms
× t) is the sum.

Specifically, the ratio of the magnitude (Ms × t) of the magnetic moment per unit area of the free magnetic layer 26 to the magnitude (Ms × t) of the magnetic moment per unit area of the ferromagnetic layer 24 ( Free magnetic layer 26 Ms × t /
The Ms × t) of the ferromagnetic layer 24 is in the range of 3 or more and 20 or less.

The second ferromagnetic layer 24b, which is the side of the ferromagnetic layer 24 in contact with the non-magnetic layer 25, is a NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ru, R
h, Hf, Ta, W, Ir, or Pt), the magnitude of the interlayer coupling magnetic field between the free magnetic layer 26 and the ferromagnetic layer 24 can be appropriately reduced. is doing.

Further, the nonmagnetic layer 25 of the free magnetic layer 26
The first magnetic layer 26a that is in contact with the NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ru, R
h, Hf, Ta, W, Ir, or Pt), the magnitude of the interlayer coupling magnetic field between the free magnetic layer 26 and the ferromagnetic layer 24 can be appropriately reduced. is doing.

In the magnetic sensing element shown in FIG. 1, the free magnetic layer 26 is made to have a single magnetic domain and the magnetization direction is controlled by the magnitude of the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24. Since the magnitude of the interlayer coupling magnetic field between the ferromagnetic layer 24 and the free magnetic layer 26 is adjusted in two steps, fine control can be easily performed.

Therefore, it is possible to properly and easily control the free magnetic layer 26 to have a single magnetic domain and control the magnetization direction, so that it is possible to promote further narrowing of the track of the magnetic detection element.

Further, even in the structure in which the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are stacked below the track width region 26c of the free magnetic layer 26 with the nonmagnetic layer 25 interposed therebetween, the magnetization of the free magnetic layer 26 is reduced. It is possible to surely orient the direction in the direction intersecting the magnetization direction of the pinned magnetic layer 28 and to change the magnetization direction of the free magnetic layer 26 by the leakage magnetic field.

Therefore, in the case of the magnetic sensing element as shown in FIG. 1, the track width region 26c of the free magnetic layer 26 is formed.
It is difficult for the magnetization direction of the free magnetic layer 26 to be different between the central portion and both end portions of the.

In the magnetic sensing element shown in FIG. 1, the multilayer film A has its both sides extending from the protective layer 30 to the middle of the first magnetic layer 26a of the free magnetic layer 26, and has a track width dimension Tw in the track width direction. The dimension of the ferromagnetic layer 24, the second antiferromagnetic layer 23, the seed layer 22, and the underlayer 21 in the track width direction is larger than the track width dimension Tw from the middle of the first magnetic layer 26a.

FIG. 2 is a partial cross-sectional view of the structure of the magnetic sensing element of the second embodiment of the present invention as seen from the side facing the recording medium, and FIG. 3 is the magnetic field of the third embodiment of the present invention. FIG. 3 is a partial cross-sectional view of the structure of the detection element as seen from the side facing the recording medium.

In the embodiment shown in FIG. 2, unlike the case of FIG. 1, the free magnetic layer 26 includes a first magnetic layer 26a and a second magnetic layer 26b.
And the intermediate magnetic layer 26d has a three-layer structure. Other than the configuration of the free magnetic layer 26, there is no difference from the magnetic detection element of FIG.

The first magnetic layer 26a in contact with the nonmagnetic layer 25
Is NiFe or NiFeX as described in FIG.
(X is Al, Si, Ti, V, Cr, Mn, Cu, Z
r, Nb, Mo, Ru, Rh, Hf, Ta, W, Ir,
One or more elements selected from Pt). Alternatively, the free magnetic layer 26 has a magnetic region made of NiFe or NiFeX on the side in contact with the non-magnetic layer 25.

The second magnetic layer 26b in contact with the non-magnetic material layer 27 is a magnetic material layer containing Co as described in FIG. Alternatively, the free magnetic layer 26 has a magnetic region made of a magnetic material containing Co on the side in contact with the nonmagnetic material layer 27. The magnetic material layer containing Co includes CoFe, CoFeNi, CoFeCr and the like.

In this embodiment, the intermediate magnetic layer 26d sandwiched between the first magnetic layer 26a and the second magnetic layer 26b.
Is provided for adjusting, for example, the magnetic moment (Ms × t) per unit area of the free magnetic layer 26, and the material of the intermediate magnetic layer 26d is determined from the viewpoint of the magnetic moment.

The material of the intermediate magnetic layer 26d is Ni, for example.
It is a magnetic material layer containing Fe, NiFeX, and Co. As an example, the first magnetic layer 26a is made of Ni _{85 at%} Fe.
_10at% Nb _5at% , the intermediate magnetic layer 26d is N
i _{80 at%} Fe _{20 at%} and the second magnetic layer 26b
Is Co _{90 at%} Fe _{10 at%} .

The first magnetic layer 26a and the intermediate magnetic layer 26d.
And the interface between the intermediate magnetic layer 26d and the second magnetic layer 26
There is a case where the boundary surface with b is not clearly understood due to thermal diffusion or the like. For example, in the above-mentioned specific example, a magnetic region made of NiFeNb exists on the side of the free magnetic layer 26 in contact with the non-magnetic layer 25, and A magnetic region made of CoFe exists on the side in contact with the magnetic material layer 27, and Ni is provided between the magnetic regions.
If there is a magnetic region made of Fe, it can be presumed that the free magnetic layer 26 is originally formed with a three-layer structure.

The free magnetic layer 26 may be composed of more layers than three layers. In FIG. 3, the free magnetic layer 26 has a single layer structure of a ferromagnetic material. The free magnetic layer 26 is made of NiFe or NiFeX (X is Al, S
i, Ti, V, Cr, Mn, Cu, Zr, Nb, Mo,
Ru, Rh, Hf, Ta, W, Ir, or Pt) is preferably used. According to the experimental results described later, when the free magnetic layer 26 is formed of a single layer structure of CoFe, the reproducing sensitivity η is low, the hysteresis is deteriorated, and the reproducing characteristics are formed by NiFe or NiFeX. It was found to be lower than that of the case.

In the embodiment shown in FIG. 3, the ferromagnetic layer 24 is used.
Also has a single-layer structure. The ferromagnetic layer 24 is made of NiFe, Ni
FeX (X is Al, Si, Ti, V, Cr, Mn, C
u, Zr, Nb, Mo, Ru, Rh, Hf, Ta, W,
One or more elements selected from Ir and Pt),
It can be formed of CoFe, CoFeCr, or the like. In order to increase the exchange coupling magnetic field with the second antiferromagnetic layer 23, the single-layer ferromagnetic layer 24 is preferably made of a ferromagnetic material containing Co.

Either one of the ferromagnetic layer 24 and the free magnetic layer 26 may have a single layer structure, and the other may have a multilayer structure made of a ferromagnetic material.

In FIGS. 2 and 3, the ferromagnetic layer 24
The ratio of the magnetic moment per unit area of the free magnetic layer 26 to the magnetic moment per unit area of 1 is the same as that explained in FIG.

Next, the multilayer film of the magnetic sensing element of the present invention is
It does not matter that the first magnetic layer 26a of the free magnetic layer 26 shown in FIG.

FIG. 4 shows a fourth embodiment of the present invention which has the same laminated structure as the multilayer film A of FIG. 1 and has a multilayer film C in which both sides B and B of the track width region are not cut. 2 is a partial cross-sectional view of the magnetic detection element of FIG.

In the magnetic sensing element of FIG. 4, the lower shield layer 20 and the upper shield layer 31 are provided with the protrusions 20a and 31a which are respectively connected to the multilayer film C. The track width dimension Tw is determined by the smaller of the dimensions of the connecting portions 20a1 and the connecting portion 31a1 of the protruding portions 20a and 31a with the multilayer film C in the track width direction. Protrusion 2
An insulating layer 33 or an insulating layer 34 made of alumina or the like is formed on both sides of 0a and the protruding portion 31a.

However, the magnetic detecting element shown in FIG.
Since the dimensions of the fixed magnetic layer 28 and the free magnetic layer 26 in the track width direction are larger than the track width dimension Tw, the external magnetic field is detected even at both sides B, B of the area of the track width dimension Tw, that is, the so-called side reading rate. Becomes larger and the magnetic track width tends to widen.

Therefore, the multi-layered film C has at least the protective layer 3.
0, the first antiferromagnetic layer 29, the pinned magnetic layer 28, and the nonmagnetic material layer 27, the both sides B, B are preferably cut so that the alternate long and short dash lines L, L are the side end faces.

However, if both sides B and B are completely removed by scraping up to the ferromagnetic layer 24 and the second antiferromagnetic layer 23, the free magnetic layer 26 is surely made into a single magnetic domain, and the magnetization direction becomes the fixed magnetic layer 28. It becomes difficult to turn in the crossing direction. Further, if both sides B and B are completely removed up to the free magnetic layer 26, the demagnetizing field of the free magnetic layer 26 in the track width direction becomes large, which makes it difficult to control the magnetic domains of the free magnetic layer, which is not preferable.

Therefore, as shown in FIG. 1, a structure in which both sides of the multilayer film A are removed up to a part of the free magnetic layer 26 is a preferable form.

As in the magnetic sensing element shown in FIG. 1, CPP (CPP) to which a current is supplied in the direction perpendicular to the film surface of the multilayer film A is used.
current Perpendicular to t
If the non-magnetic material layer 27, the pinned magnetic layer 28, and the first antiferromagnetic layer 29 are a top-type magnetic detection element on the free magnetic layer 26, the film thickness of the free magnetic layer 26 is Only part of the direction is track width dimension Tw
It is easy to form a structure having a track width direction dimension of, and a remaining portion having a track width dimension larger than the track width dimension Tw.

When a part of the free magnetic layer 26 has a dimension in the track width direction larger than the track width dimension Tw, the inside of the free magnetic layer 26 due to surface magnetic charges generated at both end portions of the free magnetic layer 26. The demagnetizing field can be reduced, and the disturbance of the magnetization direction inside the free magnetic layer 26 can be reduced.

FIG. 5 is a partial cross-sectional view of the magnetic sensing element of the fifth embodiment of the present invention as seen from the side facing the recording medium.

In the magnetic sensing element of FIG. 5, instead of the multilayer film A of FIG. 1, the underlayer 21, the seed layer 22, the first antiferromagnetic layer 29, the first pinned magnetic layer 28c, and the nonmagnetic layer are arranged in this order from the bottom. Synthetic ferripinned pinned magnetic layer 28 including intermediate layer 28b and second pinned magnetic layer 28a, and nonmagnetic material layer 2
7. Free magnetic layer 26 including second magnetic layer 26b and first magnetic layer 26a, nonmagnetic layer 25, ferromagnetic layer 24 including second ferromagnetic layer 24b and first ferromagnetic layer 24a, second antiferromagnetic layer This is different from the magnetic detection element shown in FIG. 1 in that a multilayer film D in which a layer 23 and a protective layer 30 are sequentially stacked from the bottom is formed. The magnetic detection element shown in FIG. 5 is a so-called bottom type spin valve type magnetic detection element.

In FIG. 5, the layers denoted by the same reference numerals as in FIG. 1 are formed of the same material and the same film thickness.

However, the magnetic detecting element of FIG. 5 differs from the magnetic detecting element of FIG. 1 in that the second antiferromagnetic layer 23 has an intermediate antiferromagnetic layer 23a having a thickness of 10 Å or more and 50 Å or less and 1 Å or more and 3 Å or more. Non-magnetic protective layer 2 made of noble metal having the following film thickness
It may have a multilayer structure composed of 3b and the upper antiferromagnetic layer 23c.

Intermediate antiferromagnetic layer 23a and upper antiferromagnetic layer 2
3c is an antiferromagnetic material having the same composition, specifically P mentioned above.
tMn alloy, X-Mn alloy, or Pt-Mn-
It is formed using an X'alloy.

The total film thickness of the total thickness of the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c is 80 Å or more and 3
It is less than 00Å. For example, 150Å. Since the intermediate antiferromagnetic layer 23a has a thin film thickness of 10 Å or more and 50 Å or less, it does not exhibit antiferromagnetism by itself, and the intermediate antiferromagnetic layer 23a
The upper antiferromagnetic layer 23c and the upper antiferromagnetic layer 23c become antiferromagnetic only when they are integrated with each other to generate an exchange coupling magnetic field with the ferromagnetic layer 24.

The nonmagnetic protective layer 23b has a thickness of 1 Å or more and 3 Å
The following thin film thicknesses, Ru, Re, Pd, Os, I
Since the intermediate antiferromagnetic layer 23 is formed of one or more of r, Pt, Au, Rh, Cu, and Cr.
a causes an antiferromagnetic interaction between the upper antiferromagnetic layer 23c and the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c.
Can be made to function as an integrated antiferromagnetic layer. Further, even if the material of the nonmagnetic protective layer 23b diffuses into the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c, the properties of the antiferromagnetic layer do not deteriorate.

The nonmagnetic protective layer 23b may not be present, and the second antiferromagnetic layer 23 may be composed of the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c. The second antiferromagnetic layer 23 may be a single antiferromagnetic layer.

Protective layer 30 of multilayer film D, second antiferromagnetic layer 2
3, ferromagnetic layer 24, non-magnetic layer 25, free magnetic layer 26,
The nonmagnetic material layer 27 and a part of the second pinned magnetic layer 28a have a track width dimension Tw in the track width direction.
From the middle of the pinned magnetic layer 28a, the non-magnetic intermediate layer 28b, the first pinned magnetic layer 28c, the first antiferromagnetic layer 29, and the seed layer 2
2. The dimension of the underlayer 21 in the track width direction is larger than the track width dimension Tw.

The magnetic sensing element shown in FIG. 5 has the protective layer 3
Both end surfaces Da and Da in the track width direction (X direction in the drawing) from 0 to a part of the second pinned magnetic layer 28a are continuous surfaces perpendicular to the surface Db of the multilayer film D. However, as indicated by dotted lines Da1 and Da1 in FIG. 5, both end surfaces in the track width direction from the protective layer 30 to a part of the second pinned magnetic layer 28a are inclined surfaces with respect to the surface Db of the multilayer film D. Good.

Incidentally, the optical track of the magnetic detection element of FIG.
The width Tw is determined by the dimension of the nonmagnetic material layer 27 in the track width direction.
Can be In the magnetic detection element of the present embodiment, the optical
Width Tw of 0.1 μm or less, especially 0.06 μm or less
And then 200 Gbit / in ^TwoCompatible with the above recording densities
You can

Also in the magnetic detecting element shown in FIG. 5, the magnetization direction of the ferromagnetic layer 24 is oriented in a direction intersecting the magnetization direction of the pinned magnetic layer 28 by the exchange coupling magnetic field with the second antiferromagnetic layer 23. .

The free magnetic layer 26 is the nonmagnetic layer 25.
Since it is stacked on the ferromagnetic layer 24 via the non-magnetic layer 25, the free magnetic layer 26 is converted into a single magnetic domain by the inter-layer coupling magnetic field with the ferromagnetic layer 24 via the non-magnetic layer 25, in this case, RKKY interaction, The direction is oriented to intersect the magnetization direction of the pinned magnetic layer 28.

Thus, the ferromagnetic layer 24 and the non-magnetic layer 2
When the free magnetic layer 26 is made into a single domain and the magnetization direction is controlled by the interlayer coupling magnetic field via the free magnetic layer 2, the free magnetic layer 2 is exposed by an external magnetic field such as a leakage magnetic field from the recording medium.
It is possible to suppress the disturbance of the longitudinal bias magnetic field applied to 6 and the disturbance of the magnetic domain structure of the free magnetic layer 26.

Further, in the magnetic detecting element shown in FIG. 5,
The control of the single magnetic domain and the magnetization direction of the free magnetic layer 26 is performed by controlling the magnitude of the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 and the interlayer coupling magnetic field between the ferromagnetic layer 24 and the free magnetic layer 26. Therefore, fine control can be easily performed.

Therefore, it is possible to properly and easily control the free magnetic layer 26 to have a single magnetic domain and control the magnetization direction, and it is possible to further reduce the track width of the magnetic detection element.

Further, even in the structure in which the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are laminated on the track width region 26c of the free magnetic layer 26 with the nonmagnetic layer 25 interposed therebetween, the magnetization direction of the free magnetic layer 26 is also increased. Can be reliably directed in a direction intersecting the magnetization direction of the pinned magnetic layer 28, and the magnetization direction of the free magnetic layer 26 can be changed by the leakage magnetic field.

Therefore, in the case of the magnetic sensing element as shown in FIG. 5, the track width region 26c of the free magnetic layer 26 is formed.
The magnetization direction of the free magnetic layer 26 is unlikely to be different between the central portion and both end portions of the.

Further, in the magnetic detection element shown in FIG.
The first antiferromagnetic layer 29 and the pinned magnetic layer 28 are the ferromagnetic layers 2
4 and the second antiferromagnetic layer 23, a strong exchange anisotropic magnetic field is generated between the first antiferromagnetic layer 29 and the pinned magnetic layer 28, and then the ferromagnetic layer 24 and the second antiferromagnetic layer are generated. Magnetic layer 2
It is easy to adjust the magnetization direction when the manufacturing method for generating the exchange anisotropic magnetic field is adopted in FIG.

FIG. 6 is a partial cross-sectional view of a magnetic detection element according to the sixth embodiment of the present invention as seen from the side facing a recording medium.

The magnetic sensing element shown in FIG. 6 is a top type magnetic sensing element like the magnetic sensing element shown in FIG. 1, but the free magnetic layer 38 has a magnetic moment magnitude per unit area. The first free magnetic layer 35 and the second
The free magnetic layer 37 is laminated via the non-magnetic intermediate layer 36, and the first free magnetic layer 35 and the second free magnetic layer 37 are in a ferrimagnetic state in which the magnetization directions are antiparallel, that is, a so-called synthetic ferrifree type free. It is different from the magnetic detection element of FIG. 1 in that it is a magnetic layer.

In FIG. 6, the layers denoted by the same reference numerals as those in FIG. 1 are formed of the same material and have the same film thickness, and therefore description thereof will be omitted.

The first free magnetic layer 35 is the first magnetic layer 35.
It has a two-layer structure of a and the second magnetic layer 35b. The free magnetic layer 35 may have a multilayer structure of two layers or a single layer.

The first magnetic layer 35 on the side in contact with the nonmagnetic layer 25
a is a NiFe (permalloy) layer or NiFeX
(X is Al, Si, Ti, V, Cr, Mn, Cu, Z
r, Nb, Mo, Ru, Rh, Hf, Ta, W, Ir,
One or more elements selected from Pt),
The second magnetic layer 35b on the side in contact with the non-magnetic intermediate layer 36 is C
This is a layer made of a ferromagnetic material containing Co (cobalt) such as o, CoFe, and CoFeNi.

In this embodiment, the film thickness of the first magnetic layer 35a is 40Å and the film thickness of the second magnetic layer 35b is 10Å.

The nonmagnetic intermediate layer 36 is made of Ru, Rh, Ir,
It is formed of an alloy of one or more of Cr, Re and Cu. When the non-magnetic intermediate layer 36 is formed of Ru and the free magnetic layer 38 is in the synthetic ferri state, it is preferable that the film thickness of Ru be 8Å to 11Å.

The second free magnetic layer 37 is made of Co, CoF
e, a layer made of a ferromagnetic material containing Co (cobalt) such as CoFeNi. The thickness of the second free magnetic layer 37 is 8
It is 0Å.

The second free magnetic layer 37 is made of Co (cobalt).
It is possible to prevent the material of the second free magnetic layer 37 from diffusing into the non-magnetic material layer 27 and prevent the decrease in the magnetoresistance change rate by forming the layer made of a ferromagnetic material containing a.
The combined magnetic moment per unit area of the first free magnetic layer 35 (Ms × t) and the magnetic moment per unit area of the second free magnetic layer 37 (Ms × t) are combined. The direction of the moment (Ms × t) is the magnetization direction of the free magnetic layer 38.

Also in this embodiment, the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are laminated below the track width region 38a of the free magnetic layer 38 with the nonmagnetic layer 25 interposed therebetween.

In the present embodiment, at least one of the second magnetic layer 35b and the second free magnetic layer 37 of the first free magnetic layer 35 is preferably made of a magnetic material having the following composition. .

The composition formula is represented by CoFeNi, the composition ratio of Fe is 9 atomic% or more and 17 atomic% or less, the composition ratio of Ni is 0.5 atomic% or more and 10 atomic% or less, and the remaining composition ratio is C
a magnetic material that is o.

When an intermediate layer made of a CoFe alloy or Co is formed between the second free magnetic layer 37 and the nonmagnetic material layer 27, the second magnetic layer 35b of the first free magnetic layer 35 and the second free magnetic layer 35 are formed. At least one of the layers 37 is preferably formed of a magnetic material having the following composition.

The composition formula is represented by CoFeNi, the composition ratio of Fe is 7 atomic% or more and 15 atomic% or less, the composition ratio of Ni is 5 atomic% or more and 15 atomic% or less, and the remaining composition ratio is Co. material.

Further, in the present invention, the first free magnetic layer 3
It is preferable that both the second magnetic layer 35b and the second free magnetic layer 37 of No. 5 are made of CoFeNi having the above composition.

As a result, the second free layer of the first free magnetic layer 35 is formed.
RK generated between the magnetic layer 35b and the second free magnetic layer 37
The exchange coupling magnetic field in the KY interaction can be strengthened. Specifically, the magnetic field when the antiparallel state collapses, that is, the spin-flop magnetic field (Hsf) is about 293 (kA).
/ M).

Within the above composition range, the magnetostriction of the second magnetic layer 35b of the first free magnetic layer 35 and the second free magnetic layer 37 is within the range of −3 × 10 ⁻⁶ to 3 × 10 ⁻⁶ . And the coercive force can be reduced to 790 (A / m) or less.

Also in the magnetic sensing element shown in FIG. 6, the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 is increased to change the magnetization direction of the ferromagnetic layer 24 to the magnetization of the fixed magnetic layer 28. The strength of the interlayer coupling magnetic field (RKKY interaction) between the first free magnetic layer 35 and the ferromagnetic layer 24 through the non-magnetic layer 25 is set to be stronger than the exchange coupling magnetic field while being strongly fixed in the direction intersecting the direction. By reducing the size, the first free magnetic layer 3
5 and the second free magnetic layer 37 are made to be a single magnetic domain so that the magnetization direction can be reliably oriented in the direction orthogonal to the magnetization direction of the pinned magnetic layer 28, and the magnetization direction of the free magnetic layer 38 can be changed by the leakage magnetic field. Need to be adjusted.

The exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 is increased so that the magnitude of the interlayer coupling magnetic field between the first free magnetic layer 35 and the ferromagnetic layer 24 is larger than the exchange coupling magnetic field. In order to reduce the size, in this embodiment, the ferromagnetic layer 2
The magnitude of the magnetic moment per unit area of 4 (Ms ×
t) is smaller than the magnitude (Ms × t) of the magnetic moment per unit area of the first free magnetic layer 35.

Specifically, the first relative to the magnitude (Ms × t) of the magnetic moment per unit area of the ferromagnetic layer 24
Ratio of the magnitude (Ms × t) of the magnetic moment per unit area of the free magnetic layer 35 (Ms of the first free magnetic layer ×
t / Ms × t of the ferromagnetic layer 24 is in the range of 3 or more and 20 or less. The magnitude of the magnetic moment per unit area of the first free magnetic layer 35 is determined by the first magnetic layer 35.
the magnitude of the magnetic moment per unit area of a and the second
It is the sum of the magnitudes of the magnetic moments per unit area of the magnetic layer 35b.

The second ferromagnetic layer 24b, which is the side of the ferromagnetic layer 24 in contact with the non-magnetic layer 25, is a NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ru, R
h, Hf, Ta, W, Ir, and Pt), the amount of the interlayer coupling magnetic field between the first free magnetic layer 35 and the ferromagnetic layer 24 can be appropriately adjusted. It is small.

The first magnetic layer 35a, which is the side of the first free magnetic layer 35 in contact with the nonmagnetic layer 25, is formed of a NiFe (permalloy) layer or NiFeX (X is Al, Si, T).
i, V, Cr, Mn, Cu, Zr, Nb, Mo, Ru,
Rh, Hf, Ta, W, Ir, or Pt), the amount of the interlayer coupling magnetic field between the first free magnetic layer 35 and the ferromagnetic layer 24 can be appropriately adjusted. It is small.

Also in the magnetic sensing element shown in FIG. 6, the magnetic domain of the free magnetic layer 38 is controlled to a single domain and the magnetization direction is controlled by the magnitude of the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24. Since the magnitude of the interlayer coupling magnetic field between the ferromagnetic layer 24 and the first free magnetic layer 35 is adjusted in two steps, fine control can be easily performed.

Therefore, it is possible to appropriately and easily control the free magnetic layer 38 to have a single magnetic domain and control the magnetization direction, so that it is possible to further reduce the track width of the magnetic detection element.

Further, even in the structure in which the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are laminated on the track width region 38a of the free magnetic layer 38 with the nonmagnetic layer 25 interposed therebetween, the magnetization direction of the free magnetic layer 38 is also increased. Can be reliably directed in a direction crossing the magnetization direction of the pinned magnetic layer 28, and the magnetization direction of the free magnetic layer 38 can be changed by the leakage magnetic field.

Therefore, in the case of the magnetic detecting element as shown in FIG. 6, the track width region 38a of the free magnetic layer 38 is formed.
The magnetization direction of the free magnetic layer 38 is unlikely to be different between the central portion and both end portions of the.

In the magnetic sensing element of FIG. 6, the underlayer 21, the seed layer 22, the second antiferromagnetic layer 23, the ferromagnetic layer 24, the nonmagnetic layer 25, the free magnetic layer 38, the nonmagnetic material layer 27, and the fixed magnetic layer. In the multilayer film E in which the layer 28, the first antiferromagnetic layer 29, and the protective layer 30 are stacked in this order from the bottom, the protective layer 30
Both sides up to the free magnetic layer 37 are carved to have a track width dimension Tw in the track width direction, and the nonmagnetic intermediate layer 36 to the first free magnetic layer 35, the ferromagnetic layer 24, and the second antiferromagnetic layer. The dimension in the track width direction of 23, the seed layer 22, and the base layer 21 is larger than the track width dimension Tw.
As a result, the side reading that detects the external magnetic field outside the region of the track width dimension Tw of the magnetic detection element is reduced, and the longitudinal bias magnetic field of the free magnetic layer 38 (the ferromagnetic layer 24 and the free magnetic layer 24) is sufficiently large. A magnetic field of interlayer coupling between layers 38) can be provided.

The magnetic sensing element shown in FIG. 6 has the protective layer 3
0 to the non-magnetic intermediate layer 36 in the track width direction (X in the figure).
Both end surfaces Ea, Ea in the direction) are continuous surfaces perpendicular to the surface Eb of the multilayer film E. However, FIG.
As indicated by the dotted lines Ea1 and Ea1, both end surfaces from the protective layer 30 to the nonmagnetic intermediate layer 36 in the track width direction may be inclined surfaces with respect to the surface Eb of the multilayer film E.

The optical track of the magnetic detection element of FIG.
The width Tw is determined by the dimension of the nonmagnetic material layer 27 in the track width direction.
Can be In the magnetic detection element of the present embodiment, the optical
Width Tw of 0.1 μm or less, especially 0.06 μm or less
And then 200 Gbit / in ^TwoCompatible with the above recording densities
You can

FIG. 7 is a partial cross-sectional view of the magnetic sensing element of the seventh embodiment of the present invention, as seen from the side facing the recording medium.

In the magnetic sensing element of FIG. 7, instead of the multilayer film E of FIG. 6, an underlayer 21, a seed layer 22, a first antiferromagnetic layer 29, a first pinned magnetic layer 28c, and a nonmagnetic layer are arranged in this order from the bottom. Synthetic ferripinned pinned magnetic layer 28 including intermediate layer 28b and second pinned magnetic layer 28a, and nonmagnetic material layer 2
7, a synthetic ferri-free type free magnetic layer 38 including the second free magnetic layer 37, the non-magnetic intermediate layer 36, and the first free magnetic layer 35, the non-magnetic layer 25, and the second ferromagnetic layer 24.
b, the ferromagnetic layer 24 including the first ferromagnetic layer 24a and the second ferromagnetic layer 24a.
This is different from the magnetic sensing element shown in FIG. 6 in that a multilayer film F in which an antiferromagnetic layer 23 and a protective layer 30 are sequentially stacked from the bottom is formed. The magnetic detection element shown in FIG. 6 is a so-called bottom type spin valve type magnetic detection element.

The first free magnetic layer 35 is the first magnetic layer 35.
It has a two-layer structure of a and the second magnetic layer 35b.

In FIG. 7, the layers denoted by the same reference numerals as in FIG. 6 are formed of the same material and the same film thickness.

However, unlike the magnetic detection element of FIG. 6, the second antiferromagnetic layer 23 of the magnetic detection element of FIG. 7 includes an intermediate antiferromagnetic layer 23a having a film thickness of 10 Å or more and 50 Å or less and 1 Å or more and 3 Å or more. Non-magnetic protective layer 2 made of noble metal having the following film thickness
It may have a multilayer structure composed of 3b and the upper antiferromagnetic layer 23c.

Intermediate antiferromagnetic layer 23a and upper antiferromagnetic layer 2
3c is an antiferromagnetic material having the same composition, specifically P mentioned above.
tMn alloy, X-Mn alloy, or Pt-Mn-
It is formed using an X'alloy.

The total film thickness of the total thickness of the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c is 80 Å or more and 3
It is less than 00Å. For example, 150Å. Since the intermediate antiferromagnetic layer 23a has a thin film thickness of 10 Å or more and 50 Å or less, it does not exhibit antiferromagnetism by itself, and the intermediate antiferromagnetic layer 23a
The upper antiferromagnetic layer 23c and the upper antiferromagnetic layer 23c become antiferromagnetic only when they are integrated with each other to generate an exchange coupling magnetic field with the ferromagnetic layer 24.

The non-magnetic protective layer 23b has a thickness of 1 Å or more and 3 Å
The following thin film thicknesses, Ru, Re, Pd, Os, I
Since the intermediate antiferromagnetic layer 23 is formed of one or more of r, Pt, Au, Rh, Cu, and Cr.
a causes an antiferromagnetic interaction between the upper antiferromagnetic layer 23c and the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c.
Can be made to function as an integrated antiferromagnetic layer. Further, even if the material of the nonmagnetic protective layer 23b diffuses into the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c, the properties of the antiferromagnetic layer do not deteriorate.

The second antiferromagnetic layer 23 may be composed of the intermediate antiferromagnetic layer 23a and the upper antiferromagnetic layer 23c without the nonmagnetic protective layer 23b. The second antiferromagnetic layer 23 may be a single antiferromagnetic layer.

In the magnetic sensing element shown in FIG. 7, a plurality of ferromagnetic material layers (first free magnetic layer 35, second free magnetic layer 3) having different magnetic moments per unit area are used.
7) is a synthetic ferrimagnetic state.

In the magnetic sensing element shown in FIG. 7, both sides of the multilayer film F are cut away to a part in the film thickness direction from the protective layer 30 to the second pinned magnetic layer 28a, and the track width dimension Tw.
And the dimension from the rest of the second pinned magnetic layer to the underlayer 21 in the track width direction is larger than the track width dimension Tw. As a result, it is possible to reduce the side reading that detects the external magnetic field outside the area of the track width Tw of the magnetic detection element.

The magnetic detection element shown in FIG. 7 has the protective layer 3
Both end surfaces Fa, Fa in the track width direction (X direction in the drawing) from 0 to the second pinned magnetic layer 28a are continuous surfaces perpendicular to the surface Fb of the multilayer film F. However,
As indicated by the dotted lines Fa1 and Fa1 in FIG. 7, the protective layer 3
Both end surfaces in the track width direction from 0 to the second pinned magnetic layer 28a may be inclined surfaces with respect to the surface Fb of the multilayer film F.

Incidentally, the optical track of the magnetic detection element of FIG.
The width Tw is determined by the dimension of the nonmagnetic material layer 27 in the track width direction.
Can be In the magnetic detection element of the present embodiment, the optical
Width Tw of 0.1 μm or less, especially 0.06 μm or less
And then 200 Gbit / in ^TwoCompatible with the above recording densities
You can

FIG. 8 is a partial cross-sectional view of the magnetic sensing element of the eighth embodiment of the present invention as seen from the side facing the recording medium.

In the magnetic detecting element shown in FIG. 8, the semi-metal ferromagnetic Heusler alloy layer 41 is provided between the non-magnetic material layer 27 and the free magnetic layer 26, and the pinned magnetic layer 28 and the non-magnetic material layer 27 are provided.
The magnetic sensing element shown in FIG. 1 is different from the magnetic sensing element shown in FIG. 1 only in that a semimetal ferromagnetic Heusler alloy layer 42 is formed therebetween.

In FIG. 8, the layers denoted by the same reference numerals as in FIG. 1 are formed of the same material and the same film thickness.

Semi-metallic ferromagnetic Heusler alloy layers 41, 42
Is, for example, NiMnSb (nickel manganese antimony), PtMnSb (platinum manganese antimony), Pd
MnSb (palladium manganese antimony), PtMn
Sn (platinum manganese tin), Co ₂ MnSi, Co ₂ M
nGe, Co ₂ MnSn, Co ₂ MnAl or Co ₂
Mn ₁ (Al _x Si _100-x ) ₁ (where x = 0 to
100) from any semi-metallic ferromagnetic Heusler alloy.

These semi-metallic ferromagnetic Heusler alloys are
It is a semi-metal, has a Curie temperature of 200 ° C or higher, exhibits ferromagnetism at room temperature (25 ° C), and has a specific resistance of 50 μΩ · cm.
Is.

When the CPP type magnetic sensing element has the semi-metal ferromagnetic Heusler alloy layers 41 and 42 as shown in FIG. 8, the ratio of up-spin electrons and down-spin electrons flowing in the multilayer film G can be controlled. The magnetic resistance change amount ΔR can be improved, which is preferable.

Further, the semi-metallic ferromagnetic Heusler alloy layer 41
Since it is necessary to change the magnetization direction together with the free magnetic layer 26, if the NiFe layer having high soft magnetic characteristics is in contact with the semi-metal ferromagnetic Heusler alloy layer 41, the magnetoresistance change rate can be further improved. It is possible and preferable.

The magnetic sensing element shown in FIGS. 1 to 8 is
The magnetic detection element was a CPP type in which a sense current was passed in the direction perpendicular to the film surfaces of the multilayer films A, C, D, E, F, and G.

However, in the present invention, a so-called CIP (Curren) is used in which a sense current is passed in the horizontal direction of the film surface of a multilayer film having a pinned magnetic layer, a non-magnetic material layer and a free magnetic layer.
It can also be applied to a spin valve type magnetic detection element of the tIn the Plane type.

FIG. 9 is a partial cross-sectional view of a CIP type spin valve type magnetic sensing element as seen from the side facing a recording medium, as a ninth embodiment of the present invention.

The magnetic detecting element shown in FIG. 9 has a multilayer film A as in the magnetic detecting element of FIG. However, on the upper surface Ab of the multilayer film A, with a space of the track width dimension Tw,
It differs from the magnetic detection element of FIG. 1 in that a pair of electrode layers 50, 50 is formed. Therefore, in the magnetic detection element of FIG. 9, the sense current flows in the horizontal direction of the film surface of the multilayer film A. The electrode layers 50, 50 are made of W, Ta, Cr, Cu, Rh,
It is formed by using Ir, Ru, Au or the like as a material. Reference numeral 51 is a lower gap layer, and reference numeral 52 is an upper gap layer.

The magnetic detection element of FIG. 9 is also a spin valve type magnetic detection element, and the magnetization direction of the pinned magnetic layer 28 is properly pinned in the direction parallel to the Y direction in the drawing, and the magnetization of the free magnetic layer is properly magnetized. The magnetizations of the fixed magnetic layer and the free magnetic layer are orthogonal to each other in the X direction shown in the drawing. The leakage magnetic field from the recording medium penetrates in the Y direction of the magnetic sensing element,
The magnetization of the free magnetic layer fluctuates with high sensitivity, the electric resistance changes due to the relationship between the fluctuation of the magnetization direction and the fixed magnetization direction of the fixed magnetic layer, and the voltage change based on the change of the electric resistance value causes a change in the recording medium. The stray magnetic field is detected.

However, it is the relative angle between the magnetization direction of the second pinned magnetic layer 28a and the magnetization direction of the free magnetic layer 26 that directly contributes to the change (output) of the electric resistance value, and these relative angles are the detected currents. It is preferable that they are orthogonal to each other in a state where they are energized and a signal magnetic field is not applied.

The recording medium facing the surface of the magnetic detecting element facing the recording medium moves in the Z direction in the figure.

Also in the magnetic sensing element shown in FIG. 9, the magnetic domain of the free magnetic layer 26 is controlled to a single domain and the magnetization direction is controlled by the magnitude of the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24. Since the magnitude of the interlayer coupling magnetic field between the ferromagnetic layer 24 and the free magnetic layer 26 is adjusted in two steps, fine control can be easily performed.

Therefore, it is possible to properly and easily control the free magnetic layer 26 to have a single magnetic domain and control the magnetization direction, so that it is possible to further reduce the track width of the magnetic detection element.

In the structure in which the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are stacked below the track width region 26c of the free magnetic layer 26 with the nonmagnetic layer 25 interposed, the magnetization of the free magnetic layer 26 is also reduced. It is possible to surely orient the direction in the direction intersecting the magnetization direction of the pinned magnetic layer 28 and to change the magnetization direction of the free magnetic layer 26 by the leakage magnetic field.

Therefore, in the case of the magnetic detecting element as shown in FIG. 1, the track width region 26c of the free magnetic layer 26 is formed.
It is difficult for the magnetization direction of the free magnetic layer 26 to be different between the central portion and both end portions of the.

However, in order to improve the rate of change in magnetoresistance in the CIP type magnetic sensing element, the film thickness of the free magnetic layer 26 is preferably 30Å to 40Å, but the film thickness of the free magnetic layer 26 is set to this value. In the range, the second antiferromagnetic layer 2
3 and the ferromagnetic layer 24 to increase the exchange coupling magnetic field to strongly fix the magnetization direction of the ferromagnetic layer 24 in the direction intersecting the magnetization direction of the pinned magnetic layer 28, and to magnetize the free magnetic layer 26 into a single magnetic domain. It is difficult to adjust the magnetization direction of the free magnetic layer 26 so that it can be changed by the leakage magnetic field (external magnetic field) after ensuring that the direction is orthogonal to the magnetization direction of the pinned magnetic layer 28.

Also, the second antiferromagnetic layer 23 and the ferromagnetic layer 2
4. A shunt loss occurs due to the sense current flowing through the non-magnetic layer 25.

Therefore, the present invention is more effective when applied to a CPP type magnetic detecting element.

FIG. 10 is a plan view of the free magnetic layer 26 of the magnetic sensing element shown in FIGS. 1 to 5, 8 and 9 as viewed from above.

The arrow in the figure indicates the magnetization direction of the free magnetic layer 26 when no external magnetic field is applied to the magnetic detection element.

In the magnetic sensing element shown in FIGS. 1 to 5, 8 and 9, the magnetization direction of the ferromagnetic layer 24 is changed by the exchange coupling magnetic field with the second antiferromagnetic layer 23. It is strongly fixed in the direction intersecting with the free magnetic layer 26.
Are made into a single magnetic domain by an interlayer coupling magnetic field with the ferromagnetic layer 24 via the non-magnetic layer 25, and the magnetization direction is oriented in a direction intersecting with the magnetization direction of the pinned magnetic layer 28.

However, the magnetization direction of the free magnetic layer 26 is
It is adjusted to such an extent that it can be changed by the leakage magnetic field (external magnetic field) from the recording medium. That is, when the external magnetic field is applied, the magnetization direction of the free magnetic layer 26 moves by the angle θ1 or the angle θ2 with respect to the magnetization direction when the external magnetic field is not applied. The sum of θ1 and θ2 can be 12 ° or more. When the sum of θ1 and θ2 is 12 ° or more, the reproduction efficiency η (%) can be 10% or more.

The reproducing efficiency η (%) is η = {(maximum resistance change amount of magnetic detection element due to leakage magnetic field from recording medium) / (theoretical value of maximum resistance change amount of magnetic detection element)} ×
Defined as 100. The theoretical value of the maximum resistance change amount of the magnetic detection element is the resistance value when the magnetization directions of the free magnetic layer and the pinned magnetic layer are antiparallel and the magnetization direction of the free magnetic layer and the pinned magnetic layer is in the parallel state. It is the difference in the resistance value when.

The free magnetic layer 26 is the first magnetic layer 26.
It has a two-layer structure consisting of a and a second magnetic layer 26b.
The magnetizations of the magnetic layer 26a and the second magnetic layer 26b always face the same direction.

Further, in FIGS. 6 and 7, the free magnetic layer 38 is
The laminated ferri structure of the first free magnetic layer 35 and the second free magnetic layer 37 has a laminated ferri structure. In this case as well, the variation in magnetization of the first free magnetic layer 35 and the second free magnetic layer 37 is shown in FIG.
It can be considered the same as the variation in the magnetization of the free magnetic layer 26 described with reference to 0. However, the magnetization directions of the first free magnetic layer 35 and the second free magnetic layer 37 are kept antiparallel.

FIG. 11 shows a magnetic detection element having a form different from that of FIGS. 1 to 9. The magnetic detection element shown in FIG. 11 is a partial cross-sectional view seen from the side facing the recording medium. Figure 1
9 to 9 denote the same layers as those shown in FIG.

In the magnetic detecting element shown in FIG. 11, a pinned magnetic layer 28 is provided at least on both sides of the free magnetic layer 60 in the track width direction (X direction in the drawing) with a nonmagnetic material layer 27 interposed therebetween. A first antiferromagnetic layer 29 is formed on the above. The electrode layer 50 is provided on the first antiferromagnetic layer 29. A ferromagnetic layer 24 and a second antiferromagnetic layer 23 are stacked below the free magnetic layer 60 with a nonmagnetic layer 25 interposed therebetween.

In the magnetic sensing element shown in FIG. 11, the current from the electrode layer 50 is applied to the fixed magnetic layer 28 and the nonmagnetic material layer 2.
7 and the free magnetic layer 60 flow in the direction parallel to the film surface (X direction in the drawing), the flow direction of the current is CI described in FIG.
This is the same as in the P-type magnetic detection element, but in FIG. 11, the current flows through the layers in the order of the fixed magnetic layer 28-nonmagnetic material layer 27-free magnetic layer 50 or vice versa. It is the same as the CPP type magnetic sensing element described in FIG.

The CPP type magnetic detecting element described with reference to FIGS. 1 to 8 is expected to change to a CIP type magnetic detecting element as a structure which can be coped with in the future with higher recording density. The drawback of the magnetic detection element is that the output cannot be obtained unless the element size on the plane is considerably reduced and the total film thickness is increased. On the other hand, like the magnetic detection element shown in FIG. 11, the free magnetic layer 60 and the pinned magnetic layer 28 are arranged side by side in the track width direction (X direction in the drawing) with the nonmagnetic material layer 27 interposed therebetween, and the pinned magnetic layer 28 is arranged. With the structure in which the first antiferromagnetic layer 29 and the electrode layer 50 are stacked on top of each other, the above-described element size and total film thickness have an inverse relationship to the CPP type (that is, the "element size" in the CPP type is 11, YZ in the direction parallel to the film thickness direction (Z direction in the drawing)
Since the "total film thickness" in the CPP type corresponds to the size of the plane and corresponds to the width dimension of the free magnetic layer 60 in the track width direction (X direction in the drawing) in FIG. 11, the structure of FIG. The "planar element size" of the CPP type can be reduced, and the "total film thickness" of the CPP type can be increased. As a result, the reproduction output can be improved. Further, the resistance change rate can be improved by narrowing the track width Tw.

Further, in the magnetic detecting element shown in FIG.
To the free magnetic layer 6 as compared with the magnetic sensing element shown in FIG.
There is also an advantage that the gap between the shield layers 20 and 31 formed above and below 0, that is, the gap length can be reduced. The nonmagnetic material layer 27 has a film thickness H1 formed on both end surfaces of the free magnetic layer 60 in the track width direction, and the nonmagnetic material layer 27 is formed between the fixed magnetic layer 28 and the seed layer 22.
The thickness H2 of the non-magnetic material layer 2 formed between the fixed magnetic layer 28 and the seed layer 22 is larger than the thickness H2 of the non-magnetic material layer 2.
It is preferable because the amount of the current shunted to 7 can be reduced.
However, when the insulating layer 66 is provided below the pinned magnetic layer 28 as described later, no shunt loss of current occurs in the nonmagnetic material layer 27 on the seed layer 22, so it is necessary to consider the above points. Lost.

By the way, one of the problems of the structure of the magnetic sensing element shown in FIG. 11 is how to control the magnetization of the free magnetic layer 60 into a single magnetic domain.

Therefore, in the magnetic detecting element shown in FIG. 11, the laminated structure of the nonmagnetic layer 25, the ferromagnetic layer 24 and the second antiferromagnetic layer 23 described in FIGS. 1 to 9 is adopted.
That is, the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are laminated below the free magnetic layer 60 with the nonmagnetic layer 25 interposed therebetween. As a result, it becomes possible to properly and easily control the free magnetic layer 60 into a single magnetic domain and control the magnetization.

In the magnetic sensing element shown in FIG. 11, the pinned magnetic layer 28 only needs to be present on at least both sides of the free magnetic layer 60 in the track width direction (X direction in the drawing). 23, ferromagnetic layer 24 and non-magnetic layer 2
5, the insulating layer 66 may be filled up to an arbitrary height position, and the fixed magnetic layer 28 may be provided thereon. This makes it possible to reduce the current shunt loss.

In the magnetic sensing element shown in FIG. 11, the free magnetic layer 60 can be selected from various structures such as a single layer structure, a multilayer structure of magnetic layers, or a synthetic ferri structure. Multiple magnetic layers 6
It has a structure in which 1, 63 and 65 are laminated between respective layers with specular layers (specular reflection layers) 62 and 64 sandwiched therebetween. This structure can be adopted in any of the magnetic detection elements shown in FIGS.

The specular layers 62, 64 are made of Fe-O, Ni-O, Co-O, Co-Fe-O,
Co-Fe-Ni-O, Al-O, Al-Q-O (where Q is B, Si, N, Ti, V, Cr, Mn, Fe, C
o, one or more selected from Ni), R-O (where R
Is Cu, Ti, V, Cr, Zr, Nb, Mo, Hf, T
a, one or more oxides selected from W), Al—N,
Al-Q-N (where Q is B, Si, O, Ti, V, C
r, Mn, Fe, Co, one or more selected from Ni), RN (where R is Ti, V, Cr, Zr, N)
b, Mo, Hf, Ta, W, one or more kinds of nitrides, semi-metal Whistler alloys, etc. can be presented.

For example, the magnetic layers 61, 63 and 65 are made of Co.
The magnetic layer 6 is made of a magnetic material such as Fe.
By oxidizing the surface of 1, 63, 65 by an existing method, it becomes possible to provide the specular layers 62, 64 on the surface. Alternatively, the specular layers 62 and 64 may be formed between the magnetic layers by a sputtering method or the like.

The thickness of these specular layers 62 and 64 is very thin, and the magnetic layers 61, 62 and 65 are formed on the specular layers 62 and 64 by RKKY-like ferromagnetic coupling through the specular layers 62 and 64. Direct ferromagnetic coupling through a pinhole or the like, the specular layer 62,
A single magnetic domain is formed in the same direction by magnetostatic coupling (topological coupling or orange peel coupling) due to the interface roughness of 64.

The magnetic layer 63 provided in the center among the magnetic layers 61, 63 and 65 is thicker than the magnetic layers 61 and 65 above and below it. The magnetic layer 61 below the magnetic layer 63 has an RK generated between itself and the ferromagnetic layer 24.
The magnetization may be fixed in the track width direction (X direction in the drawing) by the KY exchange interaction, but the magnetic layer 6 in the middle is
No. 3 is in a state in which the magnetic layer 63 is weakly formed into a single magnetic domain so that the magnetization can be changed with respect to the external magnetization due to the fact that the film thickness is large and the RKKY exchange interaction is not directly exerted. It functions as the free magnetic layer 63.
The magnetic layer 65 above the magnetic layer 63 may or may not be present.

The advantage of providing the specular layers 62, 64 on each of the magnetic layers 61, 63, 65 is that, for example, the mean free path λ + of conduction electrons having upspin can be extended as compared with the conventional one, and thus the above-mentioned up The difference between the mean free path λ + of conduction electrons having spin and the mean free path λ− of conduction electrons having downspin can be increased, and the resistance change rate (ΔR / R) can be improved and the reproduction output can be improved. It is possible to achieve

Further, the nonmagnetic layer 25, the ferromagnetic layer 24 and the second antiferromagnetic layer 23 may be provided on the upper side of the free magnetic layer 60 of FIG. A method of manufacturing the magnetic sensing element shown in FIG. 1 will be described.

First, after forming an alumina layer (not shown) on a substrate (wafer which becomes a slider) not shown, a lower shield layer 20, an underlayer 21, a seed layer 22 and a second antiferromagnetic layer 23 from the bottom. , A ferromagnetic layer 24 composed of the first ferromagnetic layer 24a and the second ferromagnetic layer 24b, a non-magnetic layer 25, a free magnetic layer 26 composed of the first magnetic layer 26a and the second magnetic layer 26b, a non-magnetic material layer 27, The synthetic ferripinned pinned magnetic layer 28 including the second pinned magnetic layer 28a, the nonmagnetic intermediate layer 28b, and the first pinned magnetic layer 28c, the intermediate antiferromagnetic layer 29a, and the nonmagnetic protective layer 29b are formed by sputtering. .

As the sputtering method, for example, a sputtering method using an existing sputtering apparatus such as magnetron sputtering, RF bipolar sputtering, RF tripolar sputtering, ion beam sputtering, or opposed target type sputtering can be used. Further, in the present invention, in addition to the sputtering method and the vapor deposition method, MBE (Molecular-Beam-Epitaxy) is used.
A film forming process such as a CVD method or an ICB (ion-cluster-beam) method can be used.

In FIG. 12, the layers denoted by the same reference numerals as in FIG. 1 are formed of the same material and the same film thickness.

The intermediate antiferromagnetic layer 29a will be formed into the first antiferromagnetic layer 29a later.
The second antiferromagnetic layer 2 is a layer that constitutes the antiferromagnetic layer 29.
It is formed of a material having the same composition as 3.

Concretely, the intermediate antiferromagnetic layer 29a is set to P
tMn alloy or X-Mn (where X is Pd, I
r, Rh, Ru, Os, Ni, Fe, which is one or more elements) alloy or Pt-Mn
-X '(where X'is Pd, Ir, Rh, Ru, A
u, Ag, Os, Cr, Ni, Ar, Ne, Xe, Kr
Any one of them or two or more of them).

The nonmagnetic protective layer 29b needs to be a dense layer that is not easily oxidized by exposure to the air. In the present invention, the nonmagnetic protective layer 29b is formed using the following materials. For example, Ru, Re, Pd, Os, Ir, Pt, Au, R
It is preferable to use a material composed of one or more of h, Cu, and Cr.

By forming a film by sputtering using a noble metal such as Ru, it is possible to obtain a dense nonmagnetic protective layer 29b that is not easily oxidized by exposure to the air. Therefore, even if the thickness of the non-magnetic protective layer 29b is reduced, the fixed magnetic layer 2
8 can be appropriately prevented from being oxidized by exposure to the atmosphere.

In the present invention, it is preferable to form the nonmagnetic protective layer 29b with a thickness of 3 Å or more and 10 Å or less. More preferably, it is formed at 3 Å or more and 8 Å or less. Even with the nonmagnetic protective layer 29b having such a small thickness, it is possible to appropriately prevent the intermediate antiferromagnetic layer 29a from being oxidized by exposure to the atmosphere.

The nonmagnetic protective layer 29b having such a thin film thickness
By forming the above, the ion milling in the step of FIG. 13 can be performed with low energy, and the milling control can be improved as compared with the conventional case. This point is shown in Figure 1.
It will be described in detail in three steps.

As shown in FIG. 12, after laminating each layer from the lower shield layer 20 to the non-magnetic protective layer 29b on the substrate, the first magnetic field annealing is performed. The second antiferromagnetic layer 23 and the ferromagnetic layer 24 are heat-treated at the first heat treatment temperature while applying the first magnetic field in the track width Tw (X direction in the drawing) direction.
An exchange coupling magnetic field is generated between and to fix the magnetization of the ferromagnetic layer 24 in the X direction in the figure, that is, in the track width direction.
The free magnetic layer 26 is made into a single magnetic domain by the inter-layer coupling magnetic field acting between the non-magnetic layer 25 and the magnetic layer 24, in this case, RKKY interaction, and the magnetization direction is 1 with respect to the X direction in the drawing.
Turned 80 ° in the opposite direction. Note that, for example, the first heat temperature is 270 ° C. and the magnitude of the magnetic field is 800 k (A / m)
And The magnitude of the first magnetic field is larger than the saturation magnetic fields of the ferromagnetic layer 24 and the free magnetic layer 26.

The second antiferromagnetic layer 23 is a PtMn alloy or X-Mn (where X is Pd, Ir, Rh, R).
u, Os, Ni, Fe, alloy of Pt—Mn—X ′ (where X ′ is Pd, Ir, Rh, Ru, Au, Ag, O).
Any one of s, Cr, Ni, Ar, Ne, Xe, Kr
Or an alloy of two or more elements). Immediately after the film formation, these alloys have a disordered face-centered cubic structure (fcc), but undergo a structural transformation to a CuAuI-type ordered face-centered tetragonal structure (fct) by heat treatment. Second
The thickness of the antiferromagnetic layer is 80Å to 300Å, for example 150Å
Is.

In the PtMn alloy and the alloy represented by the formula X-Mn for forming the antiferromagnetic layer, Pt or X is preferably in the range of 37 to 63 at%. In addition, the PtMn alloy and the X
In the alloy represented by the formula —Mn, Pt or X is more preferably in the range of 47 to 57 at%. Unless otherwise specified, the upper and lower limits of the numerical range indicated by are as follows.

In addition, in the alloy represented by the formula Pt-Mn-X ', it is preferable that X' + Pt is in the range of 37 to 63 at%. Further, in the alloy represented by the formula of Pt—Mn—X ′, X ′ + Pt is 47 to 57 at%.
The range is more preferably. Further, the Pt-
In the alloy represented by the formula of Mn-X ', X'is 0.2.
It is preferably in the range of 10 at%. However,
When X ′ is any one or more of Pd, Ir, Rh, Ru, Os, Ni and Fe, X ′
Is preferably in the range of 0.2 to 40 at%.

By using these alloys and subjecting them to annealing in the first magnetic field, an antiferromagnetic layer that generates a large exchange coupling magnetic field can be obtained. In particular, PtM
For n alloy, 48 kA / m or more, for example 64 kA / m
An excellent second type having an exchange coupling magnetic field exceeding m and having a blocking temperature of 380 ° C. at which the exchange coupling magnetic field is lost.
The antiferromagnetic layer 23 can be obtained.

The intermediate antiferromagnetic layer 29a laminated on the pinned magnetic layer 28 has a thin film thickness of 10Å to 50Å, more preferably 30Å to 40Å, and thus does not exhibit antiferromagnetism or has antiferromagnetic properties. Is very weak even if
In the first magnetic field annealing, the exchange coupling magnetic field is not generated between the first pinned magnetic layer 28c and the intermediate antiferromagnetic layer 29a, and the magnetization direction of the pinned magnetic layer 28 is not fixed in the X direction in the figure.

It is considered that the noble metal element such as Ru forming the nonmagnetic protective layer 29b diffuses into the intermediate antiferromagnetic layer 29a by the above-mentioned first magnetic field annealing. Therefore, the intermediate antiferromagnetic layer 2 after the heat treatment
The constituent elements near the surface of 9a are composed of an element that constitutes the intermediate antiferromagnetic layer 29a, a noble metal element, and the like. In addition, the noble metal element or the like diffused inside the intermediate antiferromagnetic layer 29a is more on the surface side of the intermediate antiferromagnetic layer 29a than on the lower surface side of the intermediate antiferromagnetic layer 29a, and the composition ratio of the diffused precious metal element or the like is It is considered that the intermediate antiferromagnetic layer 29a gradually decreases from the surface toward the lower surface.

Further, between the first ferromagnetic layer 24a and the second ferromagnetic layer 24b forming the ferromagnetic layer 24, and further between the first magnetic layer 26a and the second magnetic layer 26b forming the free magnetic layer 26.
In the meantime, the composition easily causes thermal diffusion.

The above compositional modulation can be confirmed by an apparatus for analyzing the chemical composition of a thin film such as a SIMS analyzer.

Next, in the step shown in FIG. 13, the nonmagnetic protective layer 29b is shaved by ion milling. Non-magnetic protective layer 29b
Are left or completely removed at a film thickness of 1Å to 3Å.

In the ion milling process shown in FIG. 13, low energy ion milling can be used. The reason is that the non-magnetic protective layer 29b is formed with a very thin film thickness of about 3Å to 10Å.

Low energy ion milling is defined as ion milling using an ion beam having a beam voltage (accelerating voltage) of less than 1000V. For example, 1
A beam voltage of 50V to 500V is used. In this embodiment mode, argon (Ar) having a low beam voltage of 200 V is used.
Ion beam is used.

On the other hand, if a Ta film, for example, is used for the non-magnetic protective layer 29b, the Ta film itself is oxidized by exposure to the atmosphere. Therefore, if it is not formed with a thick film thickness of about 30 Å to 50 Å, it is sufficiently underneath. Layer cannot be protected from oxidation,
Moreover, the Ta film has a large volume due to oxidation, and the film thickness of the Ta film rises to about 50 Å or more.

To remove such a thick Ta film by ion milling, Ta is removed by high energy ion milling.
The film needs to be removed, and when high energy ion milling is used, it is very difficult to control the milling so that only the Ta film is removed.

Therefore, the intermediate antiferromagnetic layer 29a formed under the Ta film is also deeply cut, and the intermediate antiferromagnetic layer 29a is removed.
In addition, an inert gas such as Ar used at the time of ion milling may enter from the exposed surface of the intermediate antiferromagnetic layer 29a, or the crystal structure of the surface portion of the intermediate antiferromagnetic layer 29a may be broken to cause a lattice defect. (Mixing effect)
Due to these damages, the magnetic characteristics of the intermediate antiferromagnetic layer 29a are likely to deteriorate. Further, if a Ta film having a film thickness of about 50 Å or more is shaved by low energy ion milling, it takes a long processing time and becomes impractical. Further, Ta is an intermediate antiferromagnetic layer 29 at the time of film formation, as compared with the above-mentioned noble metal.
Even if only the Ta film can be removed by shaving, it is easy to diffuse into the a and remove the T film on the exposed surface of the intermediate antiferromagnetic layer 29a.
a is mixed. Intermediate antiferromagnetic layer 29a mixed with Ta
Has deteriorated antiferromagnetic properties.

On the other hand, in the present invention, the nonmagnetic protective layer 29b can be removed by low energy ion milling. The low-energy ion milling has a slow milling rate, and the margin at the milling stop position can be narrowed. In particular, it becomes possible to stop the milling at the moment when the nonmagnetic protective layer 29b is removed by ion milling.
Therefore, the intermediate antiferromagnetic layer 29a is not significantly damaged by the ion milling. The incident angle of the ion milling in the step of FIG.
It is preferably 30 ° to 70 ° from the direction normal to the surface b. Further, the processing time of ion milling is about 1 minute.

However, if the non-magnetic protective layer 29b is completely removed, the surface of the intermediate antiferromagnetic layer 29a may be damaged by ion milling and antiferromagnetism may be lowered.
It is preferable to leave the non-magnetic protective layer 29b with a film thickness of 1Å to 3Å.

Next, the step of FIG. 14 is performed. In the process of FIG. 14,
When the intermediate antiferromagnetic layer 29a or the nonmagnetic protective layer 29b is not completely removed, the remaining nonmagnetic protective layer 29b is left.
An upper antiferromagnetic layer 29c is formed thereon in vacuum, and a protective layer 30 is continuously formed in vacuum. The above-mentioned sputtering or vapor deposition method can be used for the film formation. The layers from the base layer 21 to the protective layer 30 form the multilayer film A.

The material used for the upper antiferromagnetic layer 29c is an antiferromagnetic material having the same composition as the antiferromagnetic material used for the intermediate antiferromagnetic layer 29a, specifically, the above-mentioned PtMn alloy, X-- It is preferably formed of a Mn alloy or a Pt—Mn—X ′ alloy.

In FIG. 14, the intermediate antiferromagnetic layer 29a, the remaining nonmagnetic protective layer 29b, and the upper antiferromagnetic layer 29 are shown.
c together form the first antiferromagnetic layer 29.
When the nonmagnetic protective layer 29b is completely removed, the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c are integrated to form the first antiferromagnetic layer 29.

The total film thickness of the total thickness of the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c is 80 Å or more and 5
It is less than 00Å. For example, 150Å. As described above, the intermediate antiferromagnetic layer 29a has a thickness of 10 Å or more and is 5
Since it is as thin as 0 Å or less, it does not exhibit antiferromagnetism by itself, but only when the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c are integrated to exhibit antiferromagnetism, and between the pinned magnetic layer 28 and Generates an exchange coupling magnetic field.

Even if the nonmagnetic protective layer 29b remains, the thickness of the remaining nonmagnetic protective layer 29b is 1
Above Å and below 3Å, it is thin, and also Ru, Re, Pd, O
Any one of s, Ir, Pt, Au, Rh, Cu, Cr
Since the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c have antiferromagnetic interaction, the intermediate antiferromagnetic layer 29a and the nonmagnetic protective layer 2 are formed by one kind or two or more kinds.
9b and the upper antiferromagnetic layer 29c can function as an integrated antiferromagnetic layer 29. In addition, the non-magnetic protective layer 2
The antiferromagnetism does not deteriorate even if the material of 9b diffuses into the intermediate antiferromagnetic layer 29a and the upper antiferromagnetic layer 29c.

Next, second magnetic field annealing is performed. The magnetic field direction at this time is the direction perpendicular to the track width direction (Y in the figure).
Direction), that is, the direction of the leakage magnetic field from the recording medium.
In addition, this second magnetic field annealing, the second applied magnetic field,
It is smaller than the exchange anisotropic magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24, and the heat treatment temperature is set to the second antiferromagnetic layer 2
Lower than the blocking temperature of 3. This allows the first antiferromagnetic layer 2 to remain with the direction of the exchange anisotropic magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 being oriented in the track width direction.
It is possible to direct the exchange anisotropic magnetic field between the magnetic layer 9 and the pinned magnetic layer 28 in the direction of the leakage magnetic field from the recording medium (Y direction in the drawing).
Therefore, the magnetization direction of the pinned magnetic layer 28 is fixed in a direction intersecting with the magnetization directions of the ferromagnetic layer 24 and the free magnetic layer 26.

The heat treatment temperature for the second magnetic field annealing is, for example, 250 ° C., and the magnitude of the magnetic field is 8 to 30 (kA).
/ M), for example, 24 (kA / m). The magnitude of the second applied magnetic field is larger than the coercive force of the second pinned magnetic layer 28a and the first pinned magnetic layer 28c and smaller than the spin-flop magnetic field between the second pinned magnetic layer 28a and the first pinned magnetic layer 28c. .

Therefore, the first antiferromagnetic layer 29 is appropriately ordered and transformed by the second annealing in the magnetic field, and
An exchange coupling magnetic field having an appropriate magnitude is generated between the antiferromagnetic layer 29 and the pinned magnetic layer 28.

When the manufacturing method in which the multilayer film A is formed in two stages and the annealing in the magnetic field is performed twice as in the present embodiment, the first antiferromagnetic layer 29 and the second antiferromagnetic layer 29 are used. Layer 23
Can be formed using antiferromagnetic materials having the same composition.

Next, in the step shown in FIG. 15, a resist layer is formed on the upper surface of the protective layer 30 of the multilayer film A, and the resist layer is exposed and developed to form the resist layer R having the shape shown in FIG. Leave on top. The resist layer R is a resist layer having an undercut shape for lift-off, for example, and has a width dimension in the track width direction equal to the track width dimension Tw.

Next, the side portions B, B of the multilayer film A not covered with the resist layer R are ion-milled from the direction perpendicular to the surface Ab of the multilayer film A as shown in FIG. To a part of the first magnetic layer 26a of the free magnetic layer 26.

As a result of the ion milling in the step of FIG. 16, as a result of the protective layer 30 of the multilayer film A to the first magnetic layer 2 of the free magnetic layer 26.
6a has a track width dimension Tw in the middle of 6a, and the ferromagnetic layer 2 extends from the middle of the first magnetic layer 26a.
4, the dimension of the second antiferromagnetic layer 23, the seed layer 22, and the underlayer 21 in the track width direction is larger than the track width dimension Tw.

Further, both end faces Aa, Aa in the track width direction (X direction in the drawing) from the protective layer 30 to a part of the first magnetic layer 26a of the free magnetic layer 26 of the multilayer film A are the surfaces of the multilayer film A. It is a continuous surface perpendicular to Ab.
However, as indicated by dotted lines Aa1 and Aa1 in FIG. 16, the first magnetic layer 26 from the protective layer 30 to the free magnetic layer 26 is formed.
Both end surfaces in the track width direction up to a part of a may be inclined surfaces with respect to the surface Ab of the multilayer film A.

After the ion milling process, insulating layers 32 and 32 made of Al ₂ O ₃ or SiO ₂ are formed on both sides in the track width direction from the protective layer 30 to the middle of the first magnetic layer 26a of the free magnetic layer 26. . Note that the insulating material layers forming the insulating layers 32, 32 also adhere to the upper surface and side surfaces of the resist layer R. After forming the insulating layers 32, 32, the resist layer R is removed by lift-off using an organic solvent or the like.

Further, in the step of FIG. 17, the insulating layers 32, 32 are
On the protective layer 30 of the multilayer film A, the upper shield layer 31 which also serves as the upper electrode layer is formed. Thus, the magnetic sensing element shown in FIG. 1 is obtained.

In the present invention, the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 is increased to make the magnetization direction of the ferromagnetic layer 24 strong in the direction crossing the magnetization direction of the pinned magnetic layer 28. After being fixed, the magnitude of the interlayer coupling magnetic field between the free magnetic layer 26 and the ferromagnetic layer 24 is made smaller than the exchange coupling magnetic field, whereby the free magnetic layer 26 is made into a single magnetic domain and the magnetization direction is fixed. It is necessary to make sure that the magnetization direction of the free magnetic layer 26 can be changed in a direction orthogonal to the magnetization direction of the magnetic field, and that the magnetization direction of the free magnetic layer 26 can be changed by the leakage magnetic field.

The exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 is increased to increase the free magnetic layer 26 and the ferromagnetic layer 2.
In order to make the magnitude of the inter-layer coupling magnetic field between the four magnetic fields smaller than that of the exchange coupling magnetic field, the magnitude (Ms × t) of the magnetic moment per unit area of the ferromagnetic layer 24 of the free magnetic layer 26 in the step of FIG. The ferromagnetic layer 24 and the free magnetic layer 26 are formed so as to be smaller than the magnitude of the magnetic moment per unit area (Ms × t).

Specifically, the ratio of the magnitude (Ms × t) of the magnetic moment per unit area of the free magnetic layer 26 to the magnitude (Ms × t) of the magnetic moment per unit area of the ferromagnetic layer 24 ( The ratio of (Ms × t of free magnetic layer / Ms × t of ferromagnetic layer 24) is set to 3 or more and 20 or less.

The second ferromagnetic layer 24b, which is the side of the ferromagnetic layer 24 in contact with the nonmagnetic layer 25, is formed of a NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ru, R
h, Hf, Ta, W, Ir, or Pt), the magnitude of the interlayer coupling magnetic field between the free magnetic layer 26 and the ferromagnetic layer 24 can be appropriately reduced. is doing.

In addition, the nonmagnetic layer 25 of the free magnetic layer 26
The first magnetic layer 26a that is in contact with the NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ru, R
h, Hf, Ta, W, Ir, or Pt), the magnitude of the interlayer coupling magnetic field between the free magnetic layer 26 and the ferromagnetic layer 24 can be appropriately reduced. is doing.

According to the manufacturing method described above, the magnitude of the exchange coupling magnetic field between the second antiferromagnetic layer 23 and the ferromagnetic layer 24 and the magnitude of the interlayer coupling magnetic field between the ferromagnetic layer 24 and the free magnetic layer 26 are determined. Since the adjustment is performed in two steps, it is possible to easily make the free magnetic layer 26 into a single magnetic domain and finely control the magnetization direction.

Therefore, it is possible to properly and easily control the free magnetic layer 26 to have a single magnetic domain and control the magnetization direction, so that it is possible to further reduce the track width of the magnetic detection element.

Further, even in the structure in which the ferromagnetic layer 24 and the second antiferromagnetic layer 23 are stacked below the track width region 26c of the free magnetic layer 26 with the nonmagnetic layer 25 interposed therebetween, the magnetization of the free magnetic layer 26 is reduced. It is possible to surely orient the direction in the direction intersecting the magnetization direction of the pinned magnetic layer 28 and to change the magnetization direction of the free magnetic layer 26 by the leakage magnetic field. Therefore, the track width region 26c of the free magnetic layer 26
The magnetization direction of the free magnetic layer 26 is unlikely to be different between the central portion and both end portions of the.

Further, the nonmagnetic layer 25, the ferromagnetic layer 24, and the second antiferromagnetic layer 23, which are layers for applying a longitudinal bias magnetic field to the free magnetic layer 26, are formed in a solid film shape in the step of FIG. In the steps of FIGS. 15 and 16, it suffices to grind both side portions B and B of the multilayer film A, which simplifies the manufacturing process.
Further, since the accuracy of the track width dimension Tw is improved, it is easy to narrow the track.

The magnetic sensing element shown in FIGS. 4 to 9 can also be formed by using the same manufacturing method as the above-mentioned manufacturing method. In the magnetic detection element of FIG. 11, the second antiferromagnetic layer 23, the ferromagnetic layer 24, the nonmagnetic layer 25, and the free magnetic layer 60 are formed first, and then the magnetization of the free magnetic layer 60 is controlled. The layers from the second antiferromagnetic layer 23 to the free magnetic layer 60 are annealed in a magnetic field and the layers shown in FIG.
1 is processed into a substantially trapezoidal shape, a nonmagnetic material layer 27 and a pinned magnetic layer 28 are formed on both sides thereof, and a first antiferromagnetic layer 29 and an electrode layer 50 are further formed on the pinned magnetic layer 28. After forming the film, it is formed by annealing in a magnetic field for controlling the magnetization of the pinned magnetic layer 28.

In the present invention, the nonmagnetic material layer 27 of the magnetic sensing element is formed of an insulating material such as Al ₂ O ₃ or SiO ₂ to form a magnetic sensing element called a tunnel magnetoresistive effect element. You can also

The magnetic detecting element according to the present invention can be used not only for a thin film magnetic head mounted in a hard disk device, but also for a magnetic head for tape or a magnetic sensor.

Although the present invention has been described above with reference to its preferred embodiments, various modifications can be made without departing from the scope of the present invention.

The above-mentioned embodiments are merely examples, and do not limit the scope of the claims of the present invention.

[0339]

EXAMPLE In this example, the free magnetic layer 2 as shown in FIG.
6 is used above the pinned magnetic layer 28 to change the film structure of the free magnetic layer 26 and the film structure of the ferromagnetic layer 24 by using the magnetic detecting element, and the free magnetic layer 26 and the ferromagnetic film at that time are changed. The preferred material used for the layer 24 and the magnetic moment per unit area of the ferromagnetic layer 24 (Ms
The ratio of the magnetic moment (Ms × t) per unit area of the free magnetic layer 26 to (× t) (Ms × t of free magnetic layer 26 / Ms × t of ferromagnetic layer 24) and the like were examined.

First, in Table 1 below, when the material and layer structure of the free magnetic layer 26 are changed,
Magnetic moment per unit area of the ferromagnetic layer 24 (Ms
Of the magnetic moment (Ms × t) of the free magnetic layer 26 per unit area (Ms × t of the free magnetic layer 26 / Ms × t of the ferromagnetic layer 24) to the reproduction sensitivity η and the hysteresis. It is a table which shows a relationship.

[0341]

[Table 1]

As shown in Table 1, in Examples 1 to 7 and Comparative Examples 1 to 3, the first ferromagnetic layer 2 of the ferromagnetic layer 24 was used.
4a is _10Å Co _80at% Fe _12at% Cr
_{8 at%} , and the second ferromagnetic layer 24b is formed with _10Å Ni.
It is formed of _{80 at%} Fe and _{20 at%} . Further, in Comparative Examples 4 to 6, the ferromagnetic layer 24 is made of Co of 20Å.
_{90 at%} Fe _{10 at%} .

In the "Free magnetic layer 26" column shown in Table 1,
The free magnetic layer 26 is set to “free”, “free”,
It is divided into three "free". Here, "free" means a layer on the side in contact with the nonmagnetic layer 25 shown in FIG. 1, and "free" means a layer on the side in contact with the nonmagnetic material layer 27 shown in FIG. “Free” represents an intermediate layer between “free” and “free”, but in Example 1, for example, it is a single layer in which free and free are united. Therefore, the free magnetic layer 26 of Example 1 has a two-layer structure. Is. This view is based on other examples in Table 1, comparative examples, and Table 2.
The same applies to the subsequent steps. Also, the free magnetic layer 2 in Table 1
The parenthesis written on each material of No. 6 is the film thickness.

In Table 1, the number of layers forming the free magnetic layer 26, the material, and the film thickness of each layer forming the free magnetic layer 26 are changed, and the magnetic moment per unit area (Ms) of the ferromagnetic layer 24 at that time is changed. Xt) free magnetic layer 26
The ratio of the magnetic moment (Ms × t) per unit area, the reproduction sensitivity η, and the hysteresis were determined. The thickness of the free magnetic layer 26 is set to be 120Å in total.

The reproducing sensitivity η was determined by (resistance change amount with respect to applied magnetic field assuming leakage magnetic field from recording medium is ± 40 Oe / maximum resistance change amount obtained in applied magnetic field range of ± 5 kOe) × 100.

The hysteresis was determined by (the amount of change in hysteresis resistance remaining at the origin of the hysteresis loop / the amount of change in resistance in an applied magnetic field of ± 40 Oe) × 100.

1 Oe (Oersted) is about 79 A /
m. Further, the above-mentioned method of obtaining the reproduction sensitivity η and the hysteresis is the same in Table 2 and thereafter.

As shown in Table 1, Examples 1 to 7 are
It was found that the reproduction characteristics were good, as it had a higher reproduction sensitivity η than Comparative Examples 1 to 6 and a small hysteresis.

Next, in Table 2 below, the materials of the first ferromagnetic layer 24a and the second ferromagnetic layer 24b constituting the ferromagnetic layer 24 are changed, and the unit area of the ferromagnetic layer 24 at that time is changed. The ratio of the magnetic moment (Ms × t) per unit area of the free magnetic layer 26 to the magnetic moment (Ms × t), the reproduction sensitivity η, and the hysteresis were obtained. The first ferromagnetic layer 24a and the second ferromagnetic layer 24b are both fixed to a film thickness of 10Å.

The free magnetic layer 26 has a two-layer structure in Example 2 and Examples 8 to 13, and the first magnetic layer 26a (that is, only free in Table 2) has a film thickness of 2.
It was formed with 0Å Ni _{85 at%} Fe _{15 at%} Nb _{5 at%} . In addition, the second magnetic layer 26b (that is, free in Table 2) is formed of Co _90at% Fe with a film thickness of _100Å.
It was formed at _{10 at%} . In Examples 14 and 15, 3
With a layered structure, the first magnetic layer 26a (that is, only free in Table 2) is made of Ni _{85 at%} Fe with a film thickness of 20 Å.
_It was formed with _{10 at%} Nb and _{5 at%} . In addition, the second magnetic layer 2
6b (that is, free in Table 2) was formed of Co _{90 at%} Fe _{10 at%} with a film thickness of 20 Å. Further, an intermediate magnetic layer (that is, free in Table 2) is formed with a film thickness of 80
Of Ni _{80 at %} Fe _{20 at%} .

[0351]

[Table 2]

It was found that all of the examples shown in Table 2 had a high reproduction sensitivity η and a small hysteresis value, and had excellent reproduction characteristics, as in the case of the examples shown in Table 1.

Next, in Table 3 below, the ferromagnetic layers 24 and
And the material of each layer constituting the free magnetic layer 26 is fixed,
The second magnetic layer 26b (which is included in the free magnetic layer 26)
In other words, gradually change the free and) film thicknesses in Table 3
It was As shown in Table 3 below,
1 ferromagnetic layer 24a is made of Co having a film thickness of 10 Å_{80 at%}Fe
_{12 at%}Cr_{8 at%}Formed by. In addition, the ferromagnetic layer 24
The second ferromagnetic layer 24b constituting the
_{80 at%}Fe_{20 at%}Formed by. Further free porcelain
The first magnetic layer 26a (that is, Table 3
Ni) with a film thickness of 20Å_{85 at%}F
e_{10 at%}Nb_{5 at%}Formed by. Free magnetic
The second magnetic layer 26b forming the layer 26 is made of Co._90at%F
e_{10 at%}Formed by.

[0354]

[Table 3]

Next, in Table 4 below, the ferromagnetic layers 24 and
And the material of each layer constituting the free magnetic layer 26 is fixed,
The thickness of the second ferromagnetic layer 24b forming the ferromagnetic layer 24
Gradually changed. As shown in Table 4 below, the ferromagnetic layer 2
The first ferromagnetic layer 24a constituting the No. 4 is formed of Co having a film thickness of 10Å
_{80 at%}Fe_{12 at%}Cr_{8 at%}Formed by. Well
The second ferromagnetic layer 24b forming the ferromagnetic layer 24 is made of Ni.
_{80 at%}Fe_{20 at %}Formed by. Further free porcelain
The first magnetic layer 26a (that is, Table 3
Ni) with a film thickness of 20Å_{85 at%}F
e_{10 at%}Nb _{5 at%}Formed by. Free magnetic
The second magnetic layer 26b forming the layer 26 has a thickness of 100Å
Co_90at%Fe_{10 at%}Formed by.

[0356]

[Table 4]

First, from Tables 3 and 4, the magnetic moment per unit area of the free magnetic layer 26 (Ms × t) relative to the magnetic moment per unit area of the ferromagnetic layer 24 (Ms × t) (M
The ratio (s × t) (hereinafter simply referred to as the ratio of magnetic moments) was determined.

It can be seen that the ratio of the magnetic moment in each of the examples shown in Tables 3 and 4 is in the range of 3 or more and 20 or less.

The larger the ratio of the magnetic moment, the more easily the free magnetic layer can move sensitively to the external magnetic field, which is preferable. However, if it is too large, then the hysteresis becomes large, the error rate becomes high, and the reproduction characteristics deteriorate. Will be forced to.

For example, looking at Comparative Examples 10 and 11 shown in Table 3, it can be seen that the ratio of the magnetic moment is large in these Examples, and therefore the reproduction sensitivity η also exceeds 50%. However, conversely, the hysteresis exceeded 3%, and it was found that the hysteresis was worse than in the examples shown in Table 3.

As described above, it is necessary to obtain the ratio of magnetic moments from both sides of the reproduction sensitivity η and the hysteresis. Looking at the examples shown in Tables 3 and 4, the ratios of magnetic moments are all 3 or more and 20 or less. The reproduction sensitivity η is 10% or more and 50% or less. Furthermore, the hysteresis is 3% or less.

Thus, by setting the ratio of the magnetic moment to 3 or more and 20 or less, the reproducing sensitivity η can be 10% or more and 50% or less, and the hysteresis can be 3% or less, and good reproducing characteristics can be obtained. I found that I can get

Next, the free magnetic layer 26 and the ferromagnetic layer 24.
The preferable materials and layer structure of are examined from Table 1 and Table 2.

For example, Comparative Examples 1 to 6 shown in Table 1 all have a magnetic moment ratio of 3 or more and 20 or less. Although the ratio of the magnetic moment is within the preferable range of the present invention, the reproduction sensitivity η is 10% or less and the hysteresis is higher than 3% because the first magnetic layer 26a of the free magnetic layer 26 is made of CoFe. It is thought that it is because it is formed in.

The first magnetic layer 26a of the free magnetic layer 26 is
Interlayer coupling occurs between the ferromagnetic layer 24 and the second ferromagnetic layer 24b. This interlayer bond must not be too strong. This is because if it is too strong, it becomes difficult for the free magnetic layer 26 to undergo magnetization reversal with respect to the external magnetic field, that is, the reproduction sensitivity η is unavoidably lowered.

However, as shown in Table 1, when CoFe is used for the first magnetic layer 26a of the free magnetic layer 26, the ferromagnetic layer 24
It is considered that the interlayer coupling with the second ferromagnetic layer 24b is strengthened. Therefore, it is considered that although the ratio of the magnetic moment is within the preferable range, the reproduction sensitivity η is decreased and the hysteresis is increased.

From this, it is understood that it is preferable not to use a Co type ferromagnetic material for the first magnetic layer 26a forming the free magnetic layer 26. Looking at the examples shown in Tables 1 to 4, all the materials used for the first magnetic layer 26a of the free magnetic layer 26 are NiFe-based alloys. Therefore, in the present invention, the first magnetic layer 26a of the free magnetic layer 26 has a NiFe alloy or a NiFeX alloy (X
Is Al, Si, Ti, V, Cr, Mn, Cu, Zr, N
b, Mo, Ru, Rh, Hf, Ta, W, Ir, and Pt are preferably used.

Next, regarding the number of layers of the free magnetic layer 26, the free magnetic layer 26 may be formed of one layer as in Examples 6 and 7 of Table 1, or, The free magnetic layer 26 may be formed of two layers as in Nos. 1 to 4, or the free magnetic layer 26 may be formed of three layers as in the fifth embodiment.

However, the free magnetic layer 26 has two layers rather than one layer.
It is preferable to be formed by more than one layer. The free magnetic layer 2
When No. 6 is formed of a NiFe-based single layer as in Examples 6 and 7, Ni or the like is likely to diffuse into the nonmagnetic material layer 27 shown in FIG. 1 and the rate of change in magnetoresistance is likely to decrease. Because. Therefore, the preferable layer structure of the free magnetic layer 26 is N on the side in contact with the non-magnetic layer 25 shown in FIG.
There is a magnetic region composed of iFe or NiFeX,
That is, there is a magnetic region made of a ferromagnetic material containing Co (cobalt) on the side in contact with the non-magnetic material layer 27.

Next, regarding the material of the ferromagnetic layer 24, in order to prevent the interlayer coupling with the free magnetic layer 26 from becoming too strong, the second ferromagnetic layer 24b of the ferromagnetic layer 24 is made of NiFe system. It is preferable to form the alloy.
Most of the examples shown in Tables 1 to 4 have such a structure. However, even if the entire ferromagnetic layer 24 is made of a CoFe-based ferromagnetic material as in Examples 11 and 12, the magnetic moment ratio is 3 or more and 20 or less,
The reproduction sensitivity η and the hysteresis are also within the preferable range.

The ferromagnetic layer 24 generates a large exchange coupling magnetic field particularly with the second antiferromagnetic layer 23 shown in FIG.
The magnetization must be firmly fixed in one direction. Therefore, a preferable material selection for the ferromagnetic layer 24 is to have a magnetic region made of a ferromagnetic material containing Co on the side in contact with the second antiferromagnetic layer 23.

The number of ferromagnetic layers may be a one-layer structure as in Examples 11 to 13 shown in Table 2 or a two-layer structure. Alternatively, it may have a three-layer structure or more.

However, it is considered that the ferromagnetic layer 24 preferably has at least a two-layer structure. The reason is,
In order to generate a large exchange coupling magnetic field with the second antiferromagnetic layer 23, a magnetic region made of a ferromagnetic material containing Co is formed on the side in contact with the second antiferromagnetic layer 23, while free magnetic properties are formed. This is because, in order to appropriately weaken the interlayer coupling with the layer 26, forming a magnetic region made of NiFe or NiFeX on the side in contact with the non-magnetic layer 25 makes it possible to manufacture a magnetic detection element having more excellent reproducing characteristics.

[0374]

According to the present invention described in detail above, the magnetization direction of the ferromagnetic layer is directed to the direction crossing the magnetization direction of the pinned magnetic layer by the exchange coupling magnetic field with the second antiferromagnetic layer. Since the free magnetic layer is laminated on the ferromagnetic layer via the non-magnetic layer, it is possible to control the free magnetic layer into a single magnetic domain and control the magnetization direction. The magnitude of the exchange coupling magnetic field between the magnetic layers and the magnitude of the magnetic coupling between the ferromagnetic layer and the free magnetic layer are 2
Since it is adjusted in stages, fine control can be easily performed.

Therefore, according to the present invention, it is possible to appropriately and easily control the free magnetic layer to have a single magnetic domain and control the magnetization direction, so that it is possible to further narrow the track of the magnetic detection element.

Further, in the present invention, even in the structure in which the ferromagnetic layer and the second antiferromagnetic layer are laminated on the track width region of the free magnetic layer with the nonmagnetic layer interposed therebetween, It is possible to reliably orient the magnetization direction in the direction perpendicular to the magnetization direction of the pinned magnetic layer and to change the magnetization direction of the free magnetic layer by the leakage magnetic field.

In the present invention, the free magnetic layer is
An interlayer coupling magnetic field with the ferromagnetic layer via the non-magnetic layer makes a single magnetic domain, and the magnetization direction can be oriented in a direction intersecting with the magnetization direction of the pinned magnetic layer.

For example, RKKY interaction occurs between the free magnetic layer and the ferromagnetic layer via the nonmagnetic layer. As a result, the free magnetic layer becomes a single magnetic domain,
The magnetization direction is oriented in a direction intersecting with the magnetization direction of the pinned magnetic layer.

As described above, in the present invention, the free magnetic layer is controlled to have a single magnetic domain and the magnetization direction is controlled by the interlayer coupling magnetic field with the ferromagnetic layer via the nonmagnetic layer. External magnetic fields such as
It is possible to prevent the longitudinal bias magnetic field applied to the free magnetic layer from being disturbed and disturbing the magnetic domain structure of the free magnetic layer.

[Brief description of drawings]

FIG. 1 is a sectional view of a magnetic detection element according to a first embodiment of the present invention,

FIG. 2 is a sectional view of a magnetic detection element according to a second embodiment of the present invention,

FIG. 3 is a sectional view of a magnetic detection element according to a third embodiment of the present invention,

FIG. 4 is a sectional view of a magnetic detection element according to a fourth embodiment of the present invention,

FIG. 5 is a sectional view of a magnetic detection element according to a fifth embodiment of the present invention,

FIG. 6 is a sectional view of a magnetic detection element according to a sixth embodiment of the present invention,

FIG. 7 is a sectional view of a magnetic detection element according to a seventh embodiment of the present invention,

FIG. 8 is a sectional view of a magnetic detection element according to an eighth embodiment of the present invention,

FIG. 9 is a sectional view of a magnetic detection element according to a ninth embodiment of the present invention,

FIG. 10 is a plan view of a free magnetic layer of the magnetic sensing element of the present invention,

FIG. 11 is a sectional view of a magnetic detection element according to a tenth embodiment of the present invention,

FIG. 12 is a process chart showing an embodiment of a method for manufacturing a magnetic sensing element of the present invention,

FIG. 13 is a process chart showing an embodiment of a method for manufacturing a magnetic sensing element of the present invention,

FIG. 14 is a process chart showing an embodiment of a method for manufacturing a magnetic sensing element of the present invention,

FIG. 15 is a process chart showing an embodiment of a method for manufacturing a magnetic sensing element of the present invention,

FIG. 16 is a process chart showing an embodiment of a method for manufacturing a magnetic sensing element of the present invention,

FIG. 17 is a process chart showing an embodiment of a method for manufacturing a magnetic sensing element of the present invention,

FIG. 18 is a sectional view of a conventional magnetic detection element,

FIG. 19 is a process chart showing a conventional method for manufacturing a magnetic sensing element,

FIG. 20 is a sectional view of a conventional magnetic detection element,

[Explanation of symbols]

20 Lower shield layer 21 Underlayer 22 Seed layer 23 Second antiferromagnetic layer 24 Ferromagnetic layer 25 non-magnetic layer 26, 60 Free magnetic layer 27 Non-magnetic material layer 28 Fixed magnetic layer 29 First antiferromagnetic layer 30 protective layer 31 Upper shield layer 32 insulating layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 43/10 H01L 43/10 43/12 43/12 F term (reference) 5D034 BA03 DA07 5E049 AA04 AA09 AC05 BA16 CB02 DB12

Claims (36)

[Claims] 1. A first antiferromagnetic layer, a pinned magnetic layer whose magnetization direction is fixed by the first antiferromagnetic layer, a nonmagnetic material layer, and a free magnetic layer whose magnetization direction is changed by an external magnetic field. In the magnetic sensing element having a multilayer film, the pinned magnetic layer and the free magnetic layer have a ferromagnetic material layer made of a ferromagnetic material, and the nonmagnetic layer is at least above or below the track width region of the free magnetic layer. The ferromagnetic layer and the second antiferromagnetic layer are laminated via the magnetic layer, and the magnetization direction of the ferromagnetic layer intersects the magnetization direction of the pinned magnetic layer due to the exchange coupling magnetic field with the second antiferromagnetic layer. A magnetic detection element characterized by being oriented in a direction. 2. The free magnetic layer is made into a single magnetic domain by an interlayer coupling magnetic field between the free magnetic layer and the non-magnetic layer and the magnetization direction is oriented in a direction crossing the magnetization direction of the pinned magnetic layer. The magnetic detection element according to claim 1, wherein 3. The nonmagnetic layer comprises Ru, Rh, Ir, C
The magnetic detection element according to claim 1, which is formed of an alloy of one or more of r, Re and Cu. 4. The nonmagnetic layer is formed of Ru,
The film thickness is 8Å to 11Å or 15Å to 21Å.
The magnetic detection element according to 1. 5. The magnitude of an interlayer coupling magnetic field between the free magnetic layer and the ferromagnetic layer via the non-magnetic layer is the second magnetic field.
5. The magnetic detection element according to claim 2, which has a magnitude smaller than that of an exchange coupling magnetic field between the antiferromagnetic layer and the ferromagnetic layer. 6. The magnitude of the magnetic moment per unit area of the ferromagnetic layer (Ms × t) is the magnitude of the magnetic moment per unit area of the free magnetic layer (Ms × t).
The magnetic detection element according to claim 1, which is smaller than the above. 7. The magnitude of the magnetic moment per unit area of the free magnetic layer (Ms × t) relative to the magnitude of the magnetic moment per unit area of the ferromagnetic layer (Ms × t).
The ratio of t) is in the range of 3 or more and 20 or less.
The magnetic detection element according to 1. 8. The ferromagnetic layer has a NiFe (permalloy) layer or a NiFeX (X) layer on the side in contact with the non-magnetic layer.
Is Al, Si, Ti, V, Cr, Mn, Cu, Zr, N
b, Mo, Ru, Rh, Hf, Ta, W, Ir, or Pt), and a ferromagnetic layer containing Co (cobalt) on the side in contact with the second antiferromagnetic layer. The magnetic detection element according to claim 1, which has a laminated structure that is a layer made of a material. 9. The ferromagnetic layer is NiFe (permalloy).
Is a single layer structure with a thickness of more than 0 nm and 3n
The magnetic detection element according to any one of claims 1 to 7, which has a thickness of m or less. 10. The magnetic detecting element according to claim 1, wherein the ferromagnetic layer has a single-layer structure made of CoFeCr or CoFe. 11. The NiFe (permalloy) layer or NiFeX (X is Al, Si, Ti, V, Cr, at least on the side in contact with the non-magnetic layer in the free magnetic layer.
Mn, Cu, Zr, Nb, Mo, Ru, Rh, Hf, T
11. A magnetic region comprising one or more elements selected from a, W, Ir and Pt) is present.
2. The magnetic detection element according to any one of 1. 12. The magnetic sensing element according to claim 11, wherein the free magnetic layer has a magnetic region made of a ferromagnetic material containing Co (cobalt) on a side in contact with the non-magnetic material layer. 13. The ferromagnetic material containing Co means Co
The magnetic detection element according to claim 8 or 12, which is Fe or CoFeCr. 14. The regeneration efficiency η (%) is 5 at 10% or more.
The magnetic detection element according to any one of claims 1 to 13, which is 0% or less. 15. The magnetization direction of the track width region of the free magnetic layer, when an external magnetic field is applied, is inclined by 12 ° or more with respect to the magnetization direction when the external magnetic field is not applied. The magnetic detection element according to any one of claims. 16. The multilayer film, from the bottom, the first antiferromagnetic layer, the pinned magnetic layer, the nonmagnetic material layer, the free magnetic layer, the nonmagnetic layer, the ferromagnetic layer, and the second antiferromagnetic layer. The magnetic detection element according to any one of claims 1 to 15, wherein ferromagnetic layers are stacked in this order. 17. The multilayer film, from the bottom, the second antiferromagnetic layer, the ferromagnetic layer, the nonmagnetic layer, the free magnetic layer, the nonmagnetic material layer, the pinned magnetic layer, and the first antiferromagnetic layer. The magnetic detection element according to any one of claims 1 to 15, wherein ferromagnetic layers are stacked in this order. 18. The free magnetic layer has a dimension in the track width direction of a track width dimension only in a part in the film thickness direction,
The magnetic sensing element according to claim 17, wherein the remaining portion has a dimension in the track width direction larger than the track width dimension. 19. The free magnetic layer is formed by stacking a plurality of ferromagnetic material layers having different magnetic moments per unit area via a non-magnetic intermediate layer and adjoining via the non-magnetic intermediate layer. 19. The magnetic detecting element according to claim 1, wherein the ferromagnetic material layer is in a ferrimagnetic state in which the magnetization directions are antiparallel. 20. The nonmagnetic intermediate layer comprises Ru, Rh, I
The magnetic sensing element according to claim 19, which is formed of an alloy of one or more of r, Cr, Re, and Cu. 21. The magnetic sensing element according to claim 19, wherein at least one of the plurality of ferromagnetic material layers is formed of a magnetic material having the following composition. Composition formula is CoF
The composition ratio of Fe is 9 atom% or more and 17 atom% or less, and the composition ratio of Ni is 0.5 atom% or more and 10 atom% or more.
In the following, a magnetic material in which the remaining composition ratio is Co. 22. The intermediate layer made of a CoFe alloy or Co is formed between the ferromagnetic material layer and the nonmagnetic material layer, which are stacked at the position closest to the nonmagnetic material layer. The magnetic detection element described. 23. The magnetic detecting element according to claim 22, wherein at least one of the plurality of ferromagnetic material layers is formed of a magnetic material having the following composition. The composition formula is represented by CoFeNi, the composition ratio of Fe is 7 atomic% or more and 15 atomic% or less, and N
A magnetic material in which the composition ratio of i is 5 atomic% or more and 15 atomic% or less, and the remaining composition ratio is Co. 24. The magnetic sensing element according to claim 21, wherein all layers of the plurality of ferromagnetic material layers are formed of the CoFeNi. 25. An upper electrode layer is electrically connected to an upper surface of the multilayer film, a lower electrode layer is electrically connected to a lower surface of the multilayer film, and a current is supplied in a direction perpendicular to a film surface of the multilayer film. 25. The magnetic detection element according to any one of claims 1 to 24. 26. The magnetic sensing element according to claim 1, wherein the multilayer film has a semi-metallic ferromagnetic Heusler alloy layer. 27. The magnetic sensing element according to claim 26, wherein a NiFe layer is in contact with the semi-metallic ferromagnetic Heusler alloy layer. 28. The magnetic sensing element according to claim 1, wherein the first antiferromagnetic layer and the second antiferromagnetic layer are formed of antiferromagnetic materials having the same composition. . 29. The first antiferromagnetic layer and / or the second antiferromagnetic layer is a PtMn alloy or X—Mn (where X is Pd, Ir, Rh, Ru, Os, Ni, Fe).
An alloy of any one or more of
Alternatively, Pt-Mn-X '(where X'is Pd, I
r, Rh, Ru, Au, Ag, Os, Cr, Ni, A
29. The magnetic sensing element according to claim 1, which is formed of an alloy of any one of r, Ne, Xe, and Kr or two or more elements. 30. In the multilayer film, a ferromagnetic layer and the second antiferromagnetic layer are stacked above or below the free magnetic layer with the nonmagnetic layer interposed therebetween, and at least the track width of the free magnetic layer. Has a structure in which a pinned magnetic layer is formed on both end faces in the direction with a nonmagnetic material layer interposed therebetween, and the one antiferromagnetic layer is laminated on the pinned magnetic layer, and an electrode layer is provided on the first antiferromagnetic layer. The magnetic detection element according to any one of claims 1 to 15, 19 to 21, 23, 24, 26 to 29, wherein 31. A method of manufacturing a magnetic sensing element, comprising the following steps. (A) A second antiferromagnetic layer, a ferromagnetic layer, a nonmagnetic layer, a free magnetic layer, a nonmagnetic material layer, a fixed magnetic layer, an intermediate antiferromagnetic layer, and a nonmagnetic protective layer are stacked in this order from the bottom on the substrate. And the process of
(B) performing annealing in a first magnetic field to generate an exchange coupling magnetic field between the second antiferromagnetic layer and the ferromagnetic layer, and fixing the magnetization of the ferromagnetic layer in the track width direction;
(C) removing all or part of the non-magnetic protective layer,
(D) An upper antiferromagnetic layer is formed on the nonmagnetic protective layer or the intermediate antiferromagnetic layer, and a first antiferromagnetic layer having the intermediate antiferromagnetic layer and the upper antiferromagnetic layer is formed. Process,
(E) A direction in which the second magnetic field anneal is performed to generate an exchange coupling magnetic field between the first antiferromagnetic layer and the pinned magnetic layer, and the magnetization of the pinned magnetic layer intersects the magnetization direction of the ferromagnetic layer. Step of fixing to. 32. The nonmagnetic protective layer is formed of Ru, Re, P.
The method for manufacturing a magnetic sensing element according to claim 31, wherein the magnetic sensing element is formed of any one or more of d, Os, Ir, Pt, Au, Rh, Cu, Cr. 33. The method of manufacturing a magnetic sensing element according to claim 31, wherein in the step (a), the intermediate antiferromagnetic layer is formed with a thickness of 10 Å or more and 50 Å or less. 34. The intermediate antiferromagnetic layer is 30 Å or more and 40 or more.
34. The method for manufacturing a magnetic sensing element according to claim 33, wherein the method is formed by the following steps. 35. The method according to claim 31, wherein in the step (a), the nonmagnetic protective layer is formed with a thickness of 3Å or more and 10Å or less.
A method for manufacturing a magnetic detection element according to any one of 1. 36. In the step (c), the nonmagnetic protective layer is ground or the nonmagnetic protective layer is entirely removed until the thickness of the nonmagnetic protective layer becomes 3 Å or less. 36. A method for manufacturing a magnetic detection element according to any one of items 35 to 35.