JP2003008109A - Magnetoresistive effect element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a multilayer film constituting a magnetoresistive effect element has dead regions which are affected by hard bias layers formed on both sides of the film and substantially incapable of exhibiting magnetoresistive effects near its side sections and the regions only work to raise the DC resistance of the element. SOLUTION: An electrode layer 18 is formed by extending the layer 18 onto the dead regions D of the multilayered film 16. Consequently, the DC resistance of the element can be reduced and the reproducing characteristic of the element can be improved, because a sense current from the electrode layer 18 can be made to effectively flow to the multilayered film 16 and, in addition, the joint area of the electrode layer 18 with the film 16 can be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, the electric resistance in relation to the magnetization direction of a pinned magnetic layer (Pinned magnetic layer) and the magnetization direction of a free magnetic layer affected by an external magnetic field. The present invention relates to a so-called spin-valve thin film element, and more particularly to a magnetoresistive effect element capable of improving reproduction characteristics by suppressing disturbance of the magnetization direction at both end portions of a free magnetic layer.

[0002]

2. Description of the Related Art FIG. 19 is a sectional view of a conventional structure of a magnetoresistive effect element viewed from the ABS side.

The magnetoresistive effect element shown in FIG. 19 is a GMR (giant magnetoresistiv) utilizing the giant magnetoresistive effect.
e) A type of element called a spin valve thin film element, which detects a recording magnetic field from a recording medium such as a hard disk.

This spin-valve type thin film element comprises an underlayer 6, an antiferromagnetic layer 1, a pinned magnetic layer (Pinned magnetic layer) 2, a non-magnetic conductive layer 3, a free magnetic layer (Free) 4, from the bottom.
And a multilayer film 9 including the protective layer 7, a pair of hard bias layers 5 and 5 formed on both sides of the multilayer film 9, and a pair of electrode layers formed on the hard bias layers 5 and 5. It is composed of 8 and 8. The base layer 6 and the protective layer 7 are formed of a Ta (tantalum) film or the like. The track width Tw is determined by the width of the upper surface of the multilayer film 9.

An Fe-Mn (iron-manganese) alloy film or a Ni-Mn (nickel-manganese) alloy film is used for the antiferromagnetic layer 1, and Ni-Fe is used for the pinned magnetic layer 2 and the free magnetic layer 4.
Cu is used for the (nickel-iron) alloy film and the non-magnetic conductive layer 3.
A (copper) film, a Co—Pt (cobalt-platinum) alloy film for the hard bias layers 5 and 5, and a Cr film for the electrode layers 8 and 8 are generally used.

As shown in FIG. 19, 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 antiferromagnetic layer 1. The magnetization of the free magnetic layer 4 is aligned in the X direction under the influence of the bias magnetic fields from the hard bias layers 5 and 5.

That is, the magnetization of the pinned magnetic layer 2 and the magnetization of the free magnetic layer 4 are set to be orthogonal to each other.

In this spin-valve type thin film element, a detection current (sense current) is passed from the electrode layers 8 and 8 formed on the hard bias layers 5 and 5 to the fixed magnetic layer 2, the non-magnetic conductive layer 3 and the free magnetic layer 4. ) Is given. 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.

[0009]

The free magnetic layer 4 has a three-layer structure of a first free magnetic layer, a second free magnetic layer, and a nonmagnetic material interposed therebetween. At this time, the magnetization of the first free magnetic layer and the magnetization of the second free magnetic layer are in antiferromagnetic state in which they are antiparallel to each other.

However, the free magnetic layer 4 having the three-layer structure
19 is used in the magnetoresistive effect element shown in FIG. 19, the hard bias layer 5 is magnetically connected to both the first free magnetic layer and the second free magnetic layer. There is a problem that the magnetization direction is greatly disturbed at both end portions of the 2-free magnetic layer, which affects the reproduction characteristics.

Further, in the conventional magnetoresistive effect element shown in FIG. 19, the magnetization of the pinned magnetic layer 2 is Y as shown in FIG.
The hard bias layers 5 and 5 are formed into a single magnetic domain and fixed in the direction, but are hardened in the X direction on both sides of the fixed magnetic layer 2. Therefore, in particular, the magnetizations at both ends of the pinned magnetic layer 2 are affected by the bias magnetic fields from the hard bias layers 5 and 5, and are no longer pinned in the Y direction in the drawing.

That is, the magnetization of the free magnetic layer 4 and the magnetization of the pinned magnetic layer 2 which are subjected to the X-direction magnetization of the hard bias layers 5 and 5 and are made into a single magnetic domain in the X-direction are, in particular, a multilayer film. In the vicinity of the side end portion of 9, there is no orthogonal relationship. The reason why the magnetization of the free magnetic layer 4 and the magnetization of the pinned magnetic layer 2 are set to be orthogonal to each other is that the magnetization of the free magnetic layer 4 can be easily changed even with a small external magnetic field and the electric resistance can be largely changed. This is because the reproduction sensitivity can be improved. This is because if the orthogonal relationship is obtained, an output waveform having good symmetry can be obtained.

In addition, the magnetization of the free magnetic layer 4 near its side edges is easily fixed because it is affected by the strong magnetization from the hard bias layers 5 and 5, and the magnetization is less likely to change with respect to the external magnetic field. Therefore, as shown in FIG. 19, a dead region having poor reproduction sensitivity is formed near the side edge of the multilayer film 9.

The central region of the multilayer film 9 excluding the dead region is a sensitivity region that substantially contributes to the reproduction of the recording magnetic field and exerts the magnetoresistive effect, and the width of this sensitivity region is the multilayer. It is shorter than the track width Tw set when the film 9 is formed by the width dimension of the dead region.

As described above, in the multilayer film 9 of the magnetoresistive effect element, a dead region which hardly contributes to the reproduction output is formed in the vicinity of both sides thereof, and this dead region is simply a direct current resistance value (D
It was only in the area of increasing CR).

Further, if the structure is such that the electrode layers 8 and 8 are formed only on both sides of the multilayer film 9 as in the conventional magnetoresistive effect element shown in FIG. 19, the sense current from the electrode layers 8 and 8 is increased. Results in easy flow to the hard bias layers 5 and 5, the rate of flow to the multilayer film 9 is reduced, and the presence of the insensitive region results in a drastic decrease in the amount of sense current flowing to the sensitive region. As described above, an effective amount of the sense current cannot be flowed in the sensitivity region, and there is a problem that the reproduction output is reduced as the DC resistance is increased.

The present invention is to solve the above-mentioned conventional problems, and in particular, a magnetoresistive effect element capable of suppressing the disturbance of the magnetization direction at both end portions of the free magnetic layer to improve the reproducing characteristic. It is intended to be provided.

[0018]

According to the present invention, an antiferromagnetic layer is formed in contact with the antiferromagnetic layer, and the magnetization direction is fixed by an exchange anisotropic magnetic field with the antiferromagnetic layer. A multilayer film having a magnetic layer and a free magnetic layer formed on the pinned magnetic layer via a non-magnetic conductive layer, and a magnetization direction of the free magnetic layer formed on both sides of the multilayer film. A pair of bias layers aligned in a direction intersecting with the magnetization direction of, and a pair of conductive layers formed on the bias layers, which give a detection current to the fixed magnetic layer, the nonmagnetic conductive layer, and the free magnetic layer. In the magnetoresistive effect element, in the free magnetic layer, a plurality of soft magnetic thin films are laminated with a nonmagnetic material layer interposed therebetween, and the magnetization directions of the soft magnetic thin films adjacent to each other with the nonmagnetic material layer interposed are antiparallel. In the ferrimagnetic state, Magnetic connection surface between the bias layers of the sides of the plurality of soft magnetic thin films constituting the free magnetic layer, and is characterized in that overlaps the side surface of one of the soft magnetic thin film only.

Alternatively, according to the present invention, a free magnetic layer, a nonmagnetic conductive layer formed above and below the free magnetic layer, a nonmagnetic conductive layer on one side and a nonmagnetic conductive layer on the other side are formed, A multilayer film having a pinned magnetic layer whose magnetization direction is fixed and an antiferromagnetic layer formed on one pinned magnetic layer and below the other pinned magnetic layer, and formed on both sides of the multilayer film. A pair of bias layers that align the magnetization direction of the free magnetic layer in a direction intersecting with the magnetization direction of the pinned magnetic layer,
In a magnetoresistive effect element formed on this bias layer and provided with a fixed magnetic layer, a non-magnetic conductive layer, and a pair of conductive layers for applying a detection current to the free magnetic layer, the free magnetic layer includes a plurality of soft magnetic layers. The magnetic thin films are laminated via a non-magnetic material layer, and the soft magnetic thin films adjacent via the non-magnetic material layer are in a ferrimagnetic state in which the magnetization directions are antiparallel, and the multilayer film and the bias layer are Of the plurality of soft magnetic thin films forming the free magnetic layer, and the magnetic connection surface of the above overlaps only the side surface of one soft magnetic thin film.

The free magnetic layer is a ferrimagnetic state in which a plurality of soft magnetic thin films are laminated via a nonmagnetic material layer, and the magnetization directions of the soft magnetic thin films adjacent to each other via the nonmagnetic material layer are antiparallel. When, the plurality of soft magnetic thin films,
The magnetization direction is in the direction of the magnetic field generated from the bias layer and the magnetization direction is in the opposite direction of 180 degrees, which are alternately stacked.

In the soft magnetic thin film whose magnetization direction is 180 degrees opposite to the direction of the magnetic field generated from the bias layer, the magnetization direction is disturbed in the vicinity of both side ends magnetically connected to the bias layer. I will end up. At this time, the soft magnetic thin film is adjacent to the soft magnetic thin film via the non-magnetic material layer, and has a magnetization direction near both end portions of the soft magnetic thin film whose magnetization direction is in the direction of the magnetic field generated from the bias layer. Being disturbed.

Therefore, in the bias layer, only one of the plurality of soft magnetic thin films forming the free magnetic layer may have the same magnetization direction. When the magnetization directions of one soft magnetic thin film are aligned in a fixed direction, the soft magnetic thin films adjacent to this soft magnetic thin film enter a ferrimagnetic state in which the magnetization directions are antiparallel, and eventually the magnetization directions of all the soft magnetic thin films are constant. The magnetization directions of the entire free magnetic layer are aligned in a constant direction, either parallel or antiparallel to the direction.

When the bias layer is magnetically connected to a plurality of soft magnetic thin films forming the free magnetic layer,
It is not preferable because it causes the magnetization direction to be disturbed at both ends of the soft magnetic thin film.

In the pinned magnetic layer, a plurality of soft magnetic thin films are laminated with a non-magnetic material layer interposed therebetween, and the soft magnetic thin films adjacent to each other with the non-magnetic material layer interposed therebetween have anti-parallel magnetization directions. In the ferrimagnetic state, the plurality of soft magnetic films forming the pinned magnetic layer fix the magnetization directions of the other soft magnetic films to each other, so that the magnetization direction of the pinned magnetic layer is stabilized in a fixed direction as a whole. It is possible because it is possible.

The non-magnetic material layer is made of Ru, Rh,
It is preferable to be formed of an alloy of one or more of Ir, Cr, Re and Cu.

In the present invention, the antiferromagnetic layer is PtMn.
It is preferably formed of an alloy. Alternatively, the antiferromagnetic layer is made of X-Mn (where X is Pd, Ir, R
h or Ru, which is one or more elements)
Alloy or Pt-Mn-X '(where X'is P
d, Ir, Rh, Ru, Au, Ag, which is one or more elements).

Further, in the present invention, the multilayer film is formed on both sides of the sensitivity region at the central portion where the reproduction sensitivity is excellent and the magnetoresistive effect can be substantially exerted, and the reproduction sensitivity is poor and the reproduction sensitivity is substantially low. It is preferable that the electrode layers formed on both sides of the multilayer film are formed to extend over the dead region of the multilayer film. .

In the present invention, in the sensitivity region of the multilayer film, a magnetoresistive element having electrode layers formed only on both sides of the multilayer film is scanned in the track width direction on a minute track on which a certain signal is recorded. Is defined as a region where an output of 50% or more of the maximum output of the obtained reproduction output is obtained, and the dead regions of the multilayer film are on both sides of the sensitivity region and the output is the maximum output. Is defined as a region that is 50% or less of.

Further, in the present invention, the sensitivity region of the multilayer film is preferably formed with the same width dimension as the optical track width dimension O-Tw.

Further, it is preferable that the width dimension of each electrode layer in the portion formed to extend on the multilayer film is in the range of more than 0 μm and 0.08 μm.

Further, it is more preferable that the width dimension of each electrode layer in the portion extending and formed on the multilayer film is 0.05 μm or more.

For example, even if the width dimension of the upper surface of the multilayer film formed by laminating the antiferromagnetic layer, the pinned magnetic layer, the nonmagnetic conductive layer, and the free magnetic layer is set as the track width Tw, it is actually The entire multilayer film does not exert the magnetoresistive effect, but only the central region thereof has excellent read sensitivity, and substantially only the central region is the region capable of exerting the magnetoresistive effect. The area of the multilayer film having excellent reproduction sensitivity is called a sensitivity area, and the areas having poor reproduction sensitivity on both sides of the sensitivity area are called dead areas. It is measured by the profile method. The microtrack profile method will be described below with reference to FIG.

As shown in FIG. 18, a conventional magnetoresistive effect having a multilayer film exhibiting a magnetoresistive effect, hard bias layers formed on both sides of the multilayer film, and electrode layers formed on the hard bias layer is provided. An element (see FIG. 19) is formed on the substrate. The electrode layers have a structure formed only on both sides of the multilayer film.

Next, the width dimension A of the upper surface of the multilayer film which is not covered with the electrode layer is measured by an optical microscope. The width dimension A is defined as a track width Tw measured by an optical method (hereinafter referred to as an optical track width dimension O-Tw).

Then, a certain signal is recorded in a minute track on the recording medium, and the magnetoresistive element is scanned in the track width direction on the minute track to obtain the width A of the multilayer film and the reproduction output. To measure the relationship. Alternatively, the recording medium side on which the minute tracks are formed is scanned in the track width direction on the magnetoresistive effect element, and the width dimension A of the multilayer film is
The relationship with the reproduction output may be measured. The measurement result is
It is shown on the lower side of FIG.

From the results of this measurement, it can be seen that the reproduction output is high near the center of the multilayer film and is low near the sides of the multilayer film. from this result,
In the vicinity of the center of the multilayer film, the magnetoresistive effect is satisfactorily exhibited and is involved in the reproducing function, but in the vicinity of that side, it can be said that the magnetoresistive effect is deteriorated and the reproducing output is low and the reproducing function is deteriorated. .

In the present invention, a region formed by the width dimension B of the upper surface of the multilayer film in which a reproduction output of 50% or more of the maximum reproduction output is defined as a sensitivity region, and 5 is defined as the maximum reproduction output.
A dead region is defined as a region formed with a width dimension C of the upper surface of the multilayer film that can generate a reproduction output of 0% or less.

In this dead region, the reproducing function does not work effectively, and it is only a region where the direct current resistance (DCR) is raised. Therefore, in the present invention, the electrode layer is formed to extend over the dead region. Thereby, the junction area between the multilayer film and the hard bias layer and the electrode layer formed on both sides of the multilayer film can be increased, and the sense current from the electrode layer does not go through the hard bias layer, and thus the multilayer film can be formed. Since it becomes easier to flow, it is possible to reduce the DC resistance value and improve the reproduction characteristics.

[0039]

1 is a cross-sectional view of the structure of a magnetoresistive effect element according to a first embodiment of the present invention as seen from the ABS surface side. In FIG. 1, only the central portion of the element extending in the X direction is cut away.

This magnetoresistive effect element is called a spin valve thin film element, and is a kind of GMR (giant magnetoresistive) element utilizing the giant magnetoresistive effect. This spin-valve thin film element is provided at the trailing side end of a floating slider provided in a hard disk device and detects the recording magnetic field of a hard disk. The moving direction of the magnetic recording medium such as a hard disk is the Z direction, and the direction of the leakage magnetic field from the magnetic recording medium is the Y direction.

Ta formed at the bottom of FIG.
Underlayer 10 formed of a non-magnetic material such as (tantalum)
Is.

As shown in FIG. 1, the antiferromagnetic layer 80 formed on the underlayer 10 is formed long in the X direction in the drawing.
The antiferromagnetic layer 80 is formed so as to project at the center in the X direction. Then, on the protruding antiferromagnetic layer 80, the first pinned magnetic layer 81, the nonmagnetic material layer 82, the second pinned magnetic layer 83, the nonmagnetic conductive layer 84, the first free magnetic layer 85, and the nonmagnetic material layer 86. The second free magnetic layer 87 and the protective layer 15 are formed, and the laminated body from the underlayer 10 to the protective layer 15 is configured as the multilayer film 201.

In the present invention, the antiferromagnetic layer 80 is Pt--Mn.
It is formed of a (platinum-manganese) alloy film. Alternatively, instead of the Pt-Mn alloy, X-Mn (where X is
Is one or more elements of Pd, Ir, Rh, Ru, or Pt—Mn—X ′ (where X ′ is Pd, Ir, Rh, Ru, Au, Ag). Any one kind or two or more kinds of elements) may be formed.

First fixed magnetic layer 81, second fixed magnetic layer 8
3, first free magnetic layer 85 and second free magnetic layer 87
Is a Ni-Fe (nickel-iron) alloy, Co (cobalt), Fe-Co (iron-cobalt) alloy, Fe-Co-
It is formed of a Ni alloy or the like.

The nonmagnetic conductive layer 84 is formed of a nonmagnetic conductive material having a low electric resistance such as Cu (copper).

Then, as shown in FIG. 1, the first pinned magnetic layer 81, the nonmagnetic material layer 82, and the second pinned magnetic layer 81 are arranged from above the width dimension T44 of the antiferromagnetic layer 80 formed so as to extend in the X direction in the figure. Over the side surfaces of the magnetic layer 83, the nonmagnetic conductive layer 84, and the first free magnetic layer 85, metal films 88, 88 formed of Cr or the like to serve as a buffer film and an alignment film are formed. By forming 88, the bias magnetic field generated from the hard bias layers 89, 89 described later can be increased.

Further, on the metal films 88, 88, for example, a Co-Pt (cobalt-platinum) alloy or Co-Cr- is used.
Hard bias layers 89, 89 made of a Pt (cobalt-chromium-platinum) alloy or the like are formed.

On the hard bias layers 89 and 89, intermediate layers 90 and 9 made of a non-magnetic material such as Ta.
0 is formed, and Cr, A is formed on the intermediate layers 90, 90.
Electrode layers 91, 91 made of u, Ta, W or the like are formed.

In FIG. 1, since the antiferromagnetic layer 80 extends to the lower layer of the hard bias layers 89, 89,
The film thickness of the hard bias layers 89, 89 can be reduced.
Therefore, it becomes easy to form the hard bias layers 89, 89 by a sputtering method or the like.

Further, in FIG. 1, the first pinned magnetic layer 81 and the second pinned magnetic layer 83 having different magnetic moments are
The layers laminated with the non-magnetic material layer 82 functioning as one pinned magnetic layer P.

The first pinned magnetic layer 81 is the antiferromagnetic layer 80.
By being annealed in a magnetic field, an exchange anisotropic magnetic field due to exchange coupling is generated at the interface between the first pinned magnetic layer 81 and the antiferromagnetic layer 80, and the first pinned magnetic layer is formed. The magnetization direction of the layer 81 is fixed in the Y direction in the figure. When the magnetization direction of the first pinned magnetic layer 81 is fixed in the Y direction in the drawing, the magnetization direction of the second pinned magnetic layer 83 that faces the non-magnetic material layer 82 is changed to that of the first pinned magnetic layer 81. It is fixed in a state antiparallel to the magnetization direction.

The direction of the combined magnetic moment obtained by adding the magnetic moment of the first pinned magnetic layer 81 and the magnetic moment of the second pinned magnetic layer 83 is the magnetization direction of the pinned magnetic layer P.

In this way, the magnetization directions of the first pinned magnetic layer 81 and the second pinned magnetic layer 83 are in a ferrimagnetic state in which they are antiparallel to each other, and the first pinned magnetic layer 81 and the second pinned magnetic layer 81 are in the antiferromagnetic state. Since the other magnetic direction is fixed to the pinned magnetic layer 83, the magnetization direction of the pinned magnetic layer P can be stabilized in a fixed direction as a whole, which is preferable.

In FIG. 1, the first pinned magnetic layer 81 and the second pinned magnetic layer 83 are formed by using the same material, and the respective film thicknesses are made different so that the respective magnetic moments are made different. ing.

Further, the non-magnetic material layer 82 between the first pinned magnetic layer 81 and the second pinned magnetic layer 83 is R
It is formed of an alloy of one or more of u, Rh, Ir, Cr, Re and Cu.

The first free magnetic layer 85 and the second free magnetic layer 87 are formed so that their magnetic moments are different from each other. Here again, the first free magnetic layer 85 and the second free magnetic layer 87 are formed using the same material, and the thicknesses of the first free magnetic layer 85 and the second free magnetic layer 87 are made different, so that the first free magnetic layer 85 and the second free magnetic layer 85 are formed. The magnetic moment of the free magnetic layer 87 is different.

Further, the nonmagnetic material layer 86 is made of Ru, R
It is formed of an alloy of one or more of h, Ir, Cr, Re and Cu.

In FIG. 1, the first free magnetic layer 85 and the second free magnetic layer 87, which are stacked with the non-magnetic material layer 86 interposed therebetween, function as one free magnetic layer F.

The magnetization directions of the first free magnetic layer 85 and the second free magnetic layer 87 are in antiparallel ferrimagnetic states different by 180 degrees, which is equivalent to thinning the free magnetic layer F. The effect is obtained, the saturation magnetization of the entire free magnetic layer F becomes small, the magnetization easily fluctuates, and the magnetic field detection sensitivity of the magnetoresistive effect element improves.

The direction of the synthetic magnetic moment obtained by adding the magnetic moment of the first free magnetic layer 85 and the magnetic moment of the second free magnetic layer 87 is the magnetization direction of the free magnetic layer F. However, it is the second that contributes to the output.
It is a relative angle between the magnetization direction of the pinned magnetic layer 83 and the magnetization direction of the first free magnetic layer 85.

The hard bias layers 89 and 89 are indicated by X in the drawing.
Is magnetized in the direction (track width direction), and the magnetization direction of the free magnetic layer F is the X direction in the drawing due to the bias magnetic field from the hard bias layers 89, 89 in the X direction.

However, in the regions of the free magnetic layer F in the vicinity of both end portions, the magnetization direction is disturbed, so that the reproducing sensitivity is poor and it is a dead region where the magnetoresistive effect cannot be substantially exhibited.

In this embodiment, the sensitivity area E and the dead area D of the multilayer film 201 are measured by the microtrack profile method, and as shown in FIG.
The area of the multilayer film 201 is the sensitivity area E, and the width dimension T4
Area 6 is a dead area D.

In the sensitivity region E, the magnetization direction of the pinned magnetic layer P is properly pinned in the direction parallel to the Y direction in the drawing, and the magnetization of the free magnetic layer F is properly aligned in the X direction in the drawing. The magnetizations of the fixed magnetic layer P and the free magnetic layer F have an orthogonal relationship. Then, the magnetization of the free magnetic layer F sensitively changes with respect to the external magnetic field from the recording medium, and the electric resistance changes due to the change in the magnetization direction and the fixed magnetization direction of the fixed magnetic layer P. The leakage magnetic field from the recording medium is detected by the voltage change based on the change of the resistance value. However, it is the second that directly contributes to the change (output) of the electric resistance value.
The relative angle between the magnetization direction of the pinned magnetic layer 83 and the magnetization direction of the first free magnetic layer 85 is preferably orthogonal to each other in the state where the detection current is applied and the state where the signal magnetic field is not applied.

The electrode layers 91, 91 formed on both sides of the multilayer film 201 are formed so as to extend onto the multilayer film 201, and the electrode layers 91, 91 of the multilayer film 201 without the electrode layers 91, 91 are formed. The width dimension of the upper surface is the optical track width dimension O-Tw.

The magnetic track width dimension M-Tw determined by the width dimension of the sensitivity region E whose upper surface is not covered by the electrode layers 91, 91 is the same width dimension T45 as the sensitivity region E.

In this embodiment, the electrode layers 91, 91 formed on the multilayer film 201 completely cover the dead region D,
The optical track width dimension O-Tw and the magnetic track width dimension M-Tw (= width dimension of the sensitivity region E) are formed with substantially the same width dimension.

However, the electrode layers 91, 91 formed on the multilayer film 201 may be formed shorter than that without completely covering the dead region D. At this time, the optical track width dimension O-Tw is formed larger than the magnetic track width dimension M-Tw.

As a result, in the present invention, the electrode layers 91 and 9 are provided in the multilayer film 201 without the hard bias layer 89.
The ratio of flowing the sense current from 1 can be increased.

Further, when the electrode layers 91, 91 are formed so as to extend over the dead region D, it is possible to prevent the sense current from flowing into the dead region D and generating noise.

As shown in FIG. 1, the width dimension T47 of the electrode layers 91, 91 extended and formed on the dead region D of the multilayer film 201 is specifically larger than 0 μm and 0.08.
It is preferably μm or less. In addition, the electrode layers 91, 9
The width dimension T47 of 1 is more preferably 0.05 μm or more and 0.08 μm or less.

The multilayer film 20 excluding the protective layer 15 is also provided.
1, the surface 87a of the second free magnetic layer 87 in FIG.
And the angle θ11 formed by the front end face 91a of the electrode layer 91 extending over the dead region of the multilayer film 201 is 20 degrees or more, more preferably 25 degrees or more, the sense current is shunted and dead. It is possible to prevent the noise from flowing into the area and generating noise.

However, the front surface 87a and the front end surface 9
If the angle θ11 formed by 1a is too large, when the upper shield layer made of a soft magnetic material is laminated on the protective layer 15 and the electrode layers 91, 91, the electrode layers 91, 91 and the upper shield layer are separated from each other. A short circuit is likely to occur. Therefore, the angle θ11 formed by the surface 87a and the front end surface 91a is
Is preferably 60 degrees or less, more preferably 45 degrees or less.

Further, in FIG. 1, magnetic connection surfaces M, M between the multilayer film 201 and the hard bias layers 89, 89 are formed.
However, of the side surfaces of the first free magnetic layer 85 and the second free magnetic layer 87, only the side surface of the first free magnetic layer 85 overlaps.

The hard bias layers 89, 89 need only be aligned in the magnetization direction of either the first free magnetic layer 85 or the second free magnetic layer 87. When the magnetization directions of any one of the free magnetic layers are aligned in a fixed direction, the adjacent free magnetic layers are in a ferrimagnetic state in which the magnetization directions are antiparallel, and the combined magnetic moment of the combined first and second free magnetic layers is increased. The direction is constant, and in the case of FIG. 1, they are aligned in the track width direction.

When the hard bias layers 89, 89 are magnetically connected to both the first free magnetic layer 85 and the second free magnetic layer 87, the first free magnetic layer 8 is formed.
Distortion in the magnetization direction is large at both end portions of the second free magnetic layer 87 and the second free magnetic layer 87. However, in the case of the configuration of FIG. The width T45 of E can be increased.

Further, in FIG. 1, the protective layer 15 is formed on a portion of the multilayer film 201 which is not joined to the electrode layers 91, 91, and the electrode layers 91, 91 prevent the protective layer 15 from being formed. It is directly joined to the second free magnetic layer 87 without any interposition.

Therefore, the electrode layer 9 is formed on the protective layer 15.
The electric resistance can be reduced and the characteristics of the magnetoresistive effect element can be improved as compared with the case where 1, 91 are stacked.

The multilayer film 202 of the spin-valve type thin film element shown in FIG. 2 is obtained by reversing the stacking order of the multilayer film 201 of the spin-valve type thin film element shown in FIG. That is,
In FIG. 2, the second free magnetic layer 87, the non-magnetic material layer 86, the first free magnetic layer 85, the non-magnetic conductive layer 84, the second pinned magnetic layer 83, the non-magnetic material layer 82, the 1. The fixed magnetic layer 81, the antiferromagnetic layer 80, and the protective layer 15 are continuously laminated.

In FIG. 2, the hard bias layers 89 and 8 are formed.
9 is not magnetically connected to the side surfaces of the first pinned magnetic layer 81 and the second pinned magnetic layer 83. Therefore, it is possible to prevent the magnetization directions of the first pinned magnetic layer 81 and the second pinned magnetic layer 83 aligned in the direction parallel to the Y direction in the drawing from changing due to the magnetic field applied by the hard bias layers 89. Therefore, the characteristics of the magnetoresistive effect element can be improved.

Also in FIG. 2, the first pinned magnetic layer 81 and the second pinned magnetic layer 83 having different magnetic moments are
The layers laminated with the non-magnetic material layer 82 functioning as one pinned magnetic layer P. In FIG. 2, the first pinned magnetic layer 81 and the second pinned magnetic layer 83 are formed using the same material, and the respective film thicknesses are made different, so that the respective magnetic moments are made different.

In FIG. 2 as well, the first pinned magnetic layer 81 is formed in contact with the antiferromagnetic layer 80, and is annealed in a magnetic field to give the first pinned magnetic layer 81 and the antiferromagnetic layer 80. An exchange anisotropic magnetic field due to exchange coupling is generated at the interface with and, and the magnetization direction of the first fixed magnetic layer 81 is fixed in the Y direction in the drawing. When the magnetization direction of the first pinned magnetic layer 81 is fixed in the Y direction in the drawing, the magnetization direction of the second pinned magnetic layer 83 that faces the non-magnetic material layer 82 is changed to that of the first pinned magnetic layer 81. It is fixed in a state antiparallel to the magnetization direction.
The direction of the synthetic magnetic moment obtained by adding the magnetic moment of the first pinned magnetic layer 81 and the magnetic moment of the second pinned magnetic layer 83 is the magnetization direction of the pinned magnetic layer P.

The first free magnetic layer 85 and the second free magnetic layer 87, which are laminated with the nonmagnetic material layer 86 interposed therebetween, function as one free magnetic layer F.

Here again, the first free magnetic layer 85 and the second free magnetic layer 87 are formed using the same material,
Further, by making the respective film thicknesses different, the magnetic moments of the first free magnetic layer 85 and the second free magnetic layer 87 are made different.

Also in the spin-valve type thin film element of FIG. 2, the magnetization directions of the first free magnetic layer 85 and the second free magnetic layer 87 are in the antiparallel ferrimagnetic state different by 180 degrees, and thus the free magnetic property is obtained. An effect equivalent to reducing the film thickness of the layer F is obtained, the saturation magnetization of the entire free magnetic layer F is reduced, the magnetization is likely to change, and the magnetic field detection sensitivity of the magnetoresistive effect element is improved.

The direction of the synthetic magnetic moment obtained by adding the magnetic moment of the first free magnetic layer 85 and the magnetic moment of the second free magnetic layer 87 is the magnetization direction of the free magnetic layer F.

The hard bias layers 89 and 89 are indicated by X in the drawing.
Is magnetized in the direction (track width direction), and the magnetization direction of the free magnetic layer F is the X direction in the drawing due to the bias magnetic field from the hard bias layers 89, 89 in the X direction.

However, in the regions of the free magnetic layer F in the vicinity of both end portions, the magnetization direction is disturbed, and the reproducing sensitivity is poor and it is a dead region where the magnetoresistive effect cannot be substantially exerted.

Also in this embodiment, the multilayer film 202 is used.
The sensitivity region E and the dead region D of the are measured by the microtrack profile method, and as shown in FIG.
The area of the multilayer film 202 of 48 is the sensitivity area E, and the area of the width dimension T49 is the dead area D.

In the sensitivity region E, the magnetization direction of the pinned magnetic layer P is properly pinned in the direction parallel to the Y direction in the drawing, and the magnetization of the free magnetic layer F is properly aligned in the X direction in the drawing. The magnetizations of the fixed magnetic layer P and the free magnetic layer F have an orthogonal relationship. Then, the magnetization of the free magnetic layer F sensitively changes with respect to the external magnetic field from the recording medium, and the electric resistance changes due to the change in the magnetization direction and the fixed magnetization direction of the fixed magnetic layer P. The leakage magnetic field from the recording medium is detected by the voltage change based on the change of the resistance value. However, it is the second that directly contributes to the change (output) of the electric resistance value.
The relative angle between the magnetization direction of the pinned magnetic layer 83 and the magnetization direction of the first free magnetic layer 85 is preferably orthogonal to each other in the state where the detection current is applied and the state where the signal magnetic field is not applied.

The electrode layers 91, 91 formed on both sides of the multilayer film 202 are formed so as to extend onto the multilayer film 202, and the electrode layers 91, 91 of the multilayer film 202 without the electrode layers 91, 91 are formed. The width dimension of the upper surface is the optical track width dimension O-Tw.

Further, the magnetic track width dimension M-Tw determined by the width dimension of the sensitivity region E whose upper surface is not covered with the electrode layers 91, 91 is the same width dimension T48 as the sensitivity region E.

In this embodiment, the electrode layers 91, 91 formed on the multilayer film 202 completely cover the dead region D,
The optical track width dimension O-Tw and the magnetic track width dimension M-Tw (= width dimension of the sensitivity region E) are formed with substantially the same width dimension.

However, the electrode layers 91, 91 formed on the multilayer film 202 may be formed shorter than that without completely covering the dead region D. At this time, the optical track width dimension O-Tw is formed larger than the magnetic track width dimension M-Tw.

Therefore, in the present invention, the electrode layers 91, 9 are formed in the multilayer film 202 without the hard bias layer 89.
The ratio of flowing the sense current from 1 can be increased.

Further, when the electrode layers 91, 91 are formed so as to extend over the dead region D, it is possible to prevent the sense current from flowing into the dead region D and generating noise.

The width dimension T50 of the electrode layer 91 extended and formed on the dead region D of the multilayer film 202 is specifically preferably larger than 0 μm and 0.08 μm or less. The width dimension T50 of the electrode layer 91 is 0.05
More preferably, it is not less than μm and not more than 0.08 μm.

Further, the multilayer film 20 excluding the protective layer 15
2 surface, in FIG. 2, the surface 80a of the antiferromagnetic layer 80, and the electrode layer 9 extending over the dead region of the multilayer film 202.
When the angle θ12 formed by the front end face 91a of No. 1 is 20 degrees or more, and more preferably 25 degrees or more, it is possible to prevent the sense current from being shunted and flowing into the dead region to generate noise.

However, on the protective layer 15 and the electrode layer 91,
In order to prevent a short circuit between the electrode layer 91 and the upper shield layer when the upper shield layer is laminated, the surface 80a
And the angle θ12 formed by the front end face 91a is preferably 60 degrees or less, more preferably 45 degrees or less.

Further, in FIG. 2, magnetic connection surfaces M, M between the multilayer film 202 and the hard bias layers 89, 89 are formed.
Among the side surfaces of the first free magnetic layer 85 and the second free magnetic layer 87, only the side surface of the second free magnetic layer 87 overlaps with each other. The width T48 of the sensitivity area E is suppressed by suppressing the disturbance.
Is getting bigger.

Further, in FIG. 2, the protective layer 15 is formed on the portion of the multilayer film 202 which is not joined to the electrode layers 91, 91, and the electrode layers 91, 91 serve as the protective layer 15. It is directly joined to the antiferromagnetic layer 80 without any interposition.

Therefore, the electrode layer 9 is formed on the protective layer 15.
The electric resistance can be reduced and the characteristics of the magnetoresistive effect element can be improved as compared with the case where 1, 91 are stacked.

FIG. 3 is a sectional view of the structure of another magnetoresistive effect element according to the present invention as seen from the ABS side.

In this spin valve thin film element, the first free magnetic layer 105, the second free magnetic layer 107, and the nonmagnetic conductive layer 10 are arranged above and below the nonmagnetic material layer 106 as the center.
4, 108, the first pinned magnetic layer 103, and the third pinned magnetic layer 1
09, the non-magnetic material layers 102 and 110, the second pinned magnetic layer 1
01, fourth pinned magnetic layer 111 and antiferromagnetic layers 100, 1
It is a so-called dual spin valve thin film element in which 12 is formed, and it is possible to obtain a reproduction output higher than that of the spin valve thin film element (called a single spin valve thin film element) shown in FIGS. 1 and 2. It is possible. The lowermost layer is the underlayer 10.
And the uppermost layer is the protective layer 15,
The multilayer film 203 is composed of a laminated body from the base layer 10 to the protective layer 15.

In FIG. 3, the antiferromagnetic layer 100 formed on the underlayer 10 is formed long in the X direction in the figure,
The antiferromagnetic layer 100 is formed so as to project at the center in the X direction.

In the present invention, the antiferromagnetic layers 100 and 112 are formed of Pt-Mn (platinum-manganese) alloy film. Alternatively, instead of the Pt-Mn alloy, X-Mn
(Where X is one or more elements selected from Pd, Ir, Rh, and Ru), or Pt—Mn
-X '(where X'is Pd, Ir, Rh, Ru, A
u or Ag is one or more elements)
It may be formed of.

The first free magnetic layer 105, the second free magnetic layer 107, the first pinned magnetic layer 103, the second pinned magnetic layer 101, the third pinned magnetic layer 109, and the fourth pinned magnetic layer 111. Is Ni-Fe (nickel-iron)
Alloy, Co (Cobalt), Fe-Co (Iron-Cobalt)
The nonmagnetic conductive layers 104 and 108 are made of an alloy, Fe-Co-Ni alloy, or the like, and are made of a nonmagnetic conductive material having a low electric resistance such as Cu (copper).

As shown in FIG. 3, the second pinned magnetic layer 101, the non-magnetic material layer 102, and the first pinned magnetic layer 102 are arranged from above the width dimension T51 of the antiferromagnetic layer 100 formed by extending in the X direction in the figure. Over the side surfaces of the magnetic layer 103, the non-magnetic conductive layer 104, and the first free magnetic layer 105, metal films 113 and 113 formed of Cr or the like to serve as a buffer film and an alignment film are formed. The metal films 113 and 113 are formed. By forming the, the bias magnetic field generated from the hard bias layers 114, 114 described later can be increased.

Further, on the metal films 113, 113, for example, a Co—Pt (cobalt-platinum) alloy or Co—
Hard bias layers 114, 114 made of a Cr-Pt (cobalt-chromium-platinum) alloy or the like are formed.

Further, the hard bias layers 114, 114
Above the intermediate layer 11 is formed of a non-magnetic material such as Ta.
5, 115 are formed, and the electrode layer 11 made of Cr, Au, Ta, W or the like is formed on the intermediate layers 115, 115.
6, 116 are formed.

In FIG. 3, since the antiferromagnetic layer 100 extends to the lower layer of the hard bias layers 114, 114, the hard bias layers 114, 114 can be thinned. Therefore, the hard bias layers 114 and 11
It becomes easy to form 4 by a sputtering method or the like.

Further, in FIG. 3, the first pinned magnetic layer 103 and the second pinned magnetic layer 101 having different magnetic moments are used.
However, those laminated with the non-magnetic material layer 102 interposed therebetween function as one fixed magnetic layer P ₁ . Further, the third pinned magnetic layer 109 and the fourth pinned magnetic layer 111 having different magnetic moments, which are laminated via the non-magnetic material layer 110, function as one pinned magnetic layer P ₂ .

The magnetization directions of the first pinned magnetic layer 103 and the second pinned magnetic layer 101 are antiparallel ferrimagnetic states which are different by 180 degrees, and the first pinned magnetic layer 103 is formed.
Since the second pinned magnetic layer 101 and the second pinned magnetic layer 101 fix the other magnetization direction to each other, the magnetization direction of the pinned magnetic layer P ₁ can be stabilized in a fixed direction as a whole.

In FIG. 3, the first pinned magnetic layer 103 and the second pinned magnetic layer 101 are formed using the same material,
Furthermore, by making each film thickness different, each magnetic moment is made different.

Further, the magnetization directions of the third pinned magnetic layer 109 and the fourth pinned magnetic layer 111 are also antiparallel ferrimagnetic states different by 180 degrees, and the third pinned magnetic layer 109 and the fourth pinned magnetic layer 109 are in the antiparallel state. The fixed magnetic layer 111 fixes the other magnetization direction to each other.

The non-magnetic material layers 102 and 110 are used.
Is formed of an alloy of one or more of Ru, Rh, Ir, Cr, Re and Cu.

The second pinned magnetic layer 101 and the fourth pinned magnetic layer 111 are formed in contact with the antiferromagnetic layers 100 and 112, respectively, and are annealed in a magnetic field so that the second pinned magnetic layer 101 is formed. An exchange anisotropic magnetic field due to exchange coupling is generated at the interface with the antiferromagnetic layer 100 and the interfaces with the fourth pinned magnetic layer 111 and the antiferromagnetic layer 112.

The magnetization direction of the second pinned magnetic layer 101 is
It is fixed in the Y direction shown. When the magnetization direction of the second pinned magnetic layer 101 is fixed in the Y direction shown in the figure, the magnetization direction of the first pinned magnetic layer 103 facing the non-magnetic material layer 102 is changed to that of the second pinned magnetic layer 101. It is fixed in a state antiparallel to the magnetization direction. The direction of the synthetic magnetic moment obtained by adding the magnetic moment of the second pinned magnetic layer 101 and the magnetic moment of the first pinned magnetic layer 103 is the magnetization direction of the pinned magnetic layer P ₁ .

When the magnetization direction of the second pinned magnetic layer 101 is pinned in the Y direction shown in the drawing, the fourth pinned magnetic layer 111 is formed.
The magnetization direction of is preferably fixed in the direction antiparallel to the Y direction in the drawing. At this time, the magnetization direction of the third pinned magnetic layer 109 facing the non-magnetic material layer 110 is pinned in an antiparallel direction to the magnetization direction of the fourth pinned magnetic layer 111, that is, in the Y direction. The fourth pinned magnetic layer 1
The direction of the synthetic magnetic moment obtained by adding the magnetic moment of 11 and the magnetic moment of the third pinned magnetic layer 109 is the magnetization direction of the pinned magnetic layer P ₂ .

Then, the first pinned magnetic layer 103 and the third pinned magnetic layer 103 which face each other with the first free magnetic layer 105, the non-magnetic material layer 106, and the second free magnetic layer 107 in between.
The magnetization directions of the pinned magnetic layer 109 are in antiparallel states that are different from each other by 180 degrees.

In FIG. 3, the free magnetic layer F is formed as a stack of the first free magnetic layer 105 and the second free magnetic layer 107 with the nonmagnetic material layer 106 interposed therebetween, as will be described later. The first free magnetic layer 105 and the second free magnetic layer 107 are in a ferrimagnetic state in which the magnetization directions are antiparallel.

The first free magnetic layer 105 and the second free magnetic layer 107 change the magnetization direction under the influence of the external magnetic field while maintaining the ferrimagnetic state. At this time, the first pinned magnetic layer 103 and the third pinned magnetic layer 1
When the magnetization directions of 09 are different from each other by 180 degrees in the antiparallel state, the resistance change rate of the upper layer portion of the free magnetic layer F and the resistance change rate of the lower layer portion of the free magnetic layer F become equal.

Further, it is preferable that the magnetization direction of the pinned magnetic layer P _{1 and} the magnetization direction of the pinned magnetic layer P ₂ are antiparallel.

For example, the magnitude of the magnetic moment of the second pinned magnetic layer 101 whose magnetization direction is pinned in the Y direction in the figure is made larger than the magnitude of the magnetic moment of the first pinned magnetic layer 103 so that the pinned magnetic layer is fixed. The magnetization direction of P ₁ is set to the Y direction in the figure. On the other hand, the magnitude of the magnetic moment of the third pinned magnetic layer 109 whose magnetization direction is pinned in the Y direction in the figure is made smaller than the magnitude of the magnetic moment of the fourth pinned magnetic layer 111, and the pinned magnetic layer P ₂ is The magnetization direction is made antiparallel to the Y direction in the figure.

Then, the direction of the sense current magnetic field generated when the sense current flows in the X direction in the figure and the fixed magnetic layer P.
The magnetization direction of _{1 and} the magnetization direction of the pinned magnetic layer P ₂ match, the ferrimagnetic state of the first pinned magnetic layer 103 and the second pinned magnetic layer 101, and the third pinned magnetic layer 109 and the fourth pinned layer. The ferrimagnetic state of the magnetic layer 111 is stabilized.

The first free magnetic layer 105 and the second free magnetic layer 107 are formed so that their magnetic moments are different from each other. Again, the first
The free magnetic layer 105 and the second free magnetic layer 107 are formed of the same material, and the film thicknesses of the free magnetic layer 105 and the second free magnetic layer 107 are made different, so that the magnetic properties of the first free magnetic layer 105 and the second free magnetic layer 107 are increased. Different moments.

Further, the non-magnetic material layers 102, 106, 1
10 is one of Ru, Rh, Ir, Cr, Re and Cu
It is formed of one kind or an alloy of two or more kinds.

In FIG. 3, the first free magnetic layer 105 and the second free magnetic layer 107 are the nonmagnetic material layers 10.
The layers laminated via 6 function as one free magnetic layer F.

The magnetization directions of the first free magnetic layer 105 and the second free magnetic layer 107 are antiparallel to each other in a ferrimagnetic state, and an effect equivalent to thinning the thickness of the free magnetic layer F is obtained. As a result, the saturation magnetization of the entire free magnetic layer F becomes small and the magnetization easily fluctuates, and the magnetic field detection sensitivity of the magnetoresistive effect element improves.

The direction of the synthetic magnetic moment obtained by adding the magnetic moment of the first free magnetic layer 105 and the magnetic moment of the second free magnetic layer 107 is the magnetization direction of the free magnetic layer F.

The hard bias layers 114 and 114 are magnetized in the X direction (track width direction) shown in the figure, and the free magnetic layer F is magnetized by the bias magnetic field from the hard bias layers 114 and 114 in the X direction. Direction is X shown
It is in the direction.

However, the magnetization directions are disturbed in the regions near both side ends of the first free magnetic layer 105 and the second free magnetic layer 107, and the reproducing sensitivity is poor and the magnetoresistive effect can be substantially exerted. There is no dead zone.

Also in this embodiment, the multilayer film 203 is used.
The sensitivity region E and the insensitive region D are measured by the microtrack profile method. As shown in FIG. 3, the region of the width dimension T52 located in the center of the multilayer film 203 is the sensitivity region E, and both sides thereof are located. The area having the width dimension T53 is the dead area D.

In the sensitivity region E, the pinned magnetic layers P ₁ , P ₂
Is properly pinned in a direction parallel to the Y direction in the figure, and the magnetization of the free magnetic layer F is properly aligned in the X direction in the figure, and the pinned magnetic layers P ₁ and P ₂ and the free magnetic layer F are aligned.
Are in an orthogonal relationship. Then, the magnetization of the free magnetic layer F sensitively changes with respect to the external magnetic field from the recording medium, and the electric resistance changes due to the change in the magnetization direction and the fixed magnetization direction of the fixed magnetic layers P ₁ and P _2. However, 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 first pinned magnetic layer 103 and the magnetization direction of the first free magnetic layer 105 and the magnetization direction of the third pinned magnetic layer 109 that directly contributes to the change (output) of the electric resistance value. It is a relative angle in the magnetization direction of the second free magnetic layer 107, and it is preferable that these relative angles are orthogonal to each other in a state where a detection current is applied and a signal magnetic field is not applied.

In the present invention, as shown in FIG.
03 on both sides of the hard bias layers 114, 114.
Electrode layers 116, 116 formed on the intermediate layers 115, 115 made of a non-magnetic material are formed so as to extend onto the dead region D of the multilayer film 203. The electrode layers 116, 116 are made of, for example, Cr, Au, Ta, W
It is formed of a film or the like.

The width dimension of the upper surface of the multilayer film 203 not covered with the electrode layers 116, 116 is defined as the optical track width dimension O-Tw, and the upper surface is the electrode layer 11.
Width T52 of the sensitivity region E not covered by 6,116
Is defined as the magnetic track width dimension M-Tw. In this embodiment, for example, the electrode layers 116, 116 extended on the multilayer film 203 completely cover the dead region D. In this case, the optical track width OT
w and the magnetic track width dimension M-Tw (= width dimension of the sensitivity region E) are substantially the same width dimension.

Alternatively, the electrode layers 116 and 116 may not completely cover the dead region D, and the multilayer film 203
Width dimension T54 of the electrode layers 116, 116 extended upward
May be formed shorter than the dead region D. In this case, the optical track width O-Tw is equal to the magnetic track width M.
It becomes larger than -Tw.

Thus, in the present invention, the electrode layer 11
The sense current from 6,116 is applied to the hard bias layer 11
It becomes easy to flow directly to the multilayer film 203 without passing through the electrodes 4, 114, and further, by forming the electrode layers 116, 116 so as to extend onto the dead region D, the multilayer film 203 and the electrode layers 116, 116 are bonded together. Since the area becomes large, the direct current resistance value (DCR) can be lowered, and the reproduction characteristic can be improved.

In addition, the electrode layers 116 and 116 are insensitive areas D.
When it is extended and formed, the sense current is applied to the dead region D.
It is possible to suppress the occurrence of noise flowing into the.

As shown in FIG. 3, the width dimension T of the electrode layer 116 extended and formed on the dead region D of the multilayer film 203.
Specifically, 54 is preferably more than 0 μm and 0.08 μm or less. Further, the width dimension T54 is
More preferably, it is 0.05 μm or more and 0.08 μm or less.

Further, the multilayer film 20 excluding the protective layer 15
3, the surface 112a of the antiferromagnetic layer 112 in FIG.
And an angle θ13 formed by the front end face 116a of the electrode layer 116 extended over the dead region of the multilayer film 203 is 20.
When the angle is at least 0 degree, more preferably at least 25 degrees, it is possible to suppress the generation of noise by shunting the sense current and flowing into the dead area.

However, the protective layer 15 and the electrode layers 116, 1
16 when the upper shield layer is laminated on the electrode layer 1
In order to prevent a short circuit between 16, 116 and the upper shield layer, an angle θ13 formed by the surface 112a and the front end face 116a is preferably 60 degrees or less, more preferably 45 degrees or less.

Further, in FIG. 3, a magnetic connection surface M between the multilayer film 203 and the hard bias layers 114, 114 is formed.
Among the side surfaces of the first free magnetic layer 105 and the second free magnetic layer 107, M is the first free magnetic layer 105.
The width dimension T52 of the sensitivity region E is increased by suppressing the disturbance of the magnetization direction at both end portions of both the free magnetic layers.

Further, in FIG. 3, the protective layer 15 is formed on a portion of the multilayer film 203 which is not joined to the electrode layers 116 and 116, and the electrode layers 116 and 116 are formed.
Is directly connected to the antiferromagnetic layer 112 without the protective layer 15.
It is joined with.

Therefore, the electrode layer 1 is formed on the protective layer 15.
The electric resistance can be reduced and the characteristics of the magnetoresistive effect element can be improved as compared with the case where 16 and 116 are stacked.

By using the method for manufacturing a magnetoresistive effect element described later, the magnetoresistive effect element shown in FIGS. 1 to 3 has a thin film thickness in the vicinity of the surface of the hard bias layer in contact with the multilayer film. The upper surface of the hard bias layer is
In the vicinity of the multilayer film, it is inclined or curved downward in the drawing.

As in the conventional magnetoresistive effect element shown in FIG. 19, when the upper surface of the hard bias layer projects upward in the drawing in the vicinity of the multilayer film, a leak magnetic field or a loop magnetic field is generated at this projecting portion. It was difficult to stabilize the magnetization direction of the free magnetic layer.

As shown in FIGS. 1 to 3, if the upper surface of the hard bias layer is inclined or curved in the downward direction near the multilayer film near the multilayer film, it is possible to prevent the generation of a leakage magnetic field or a loop magnetic field, so that the free magnetic field is free. The magnetization direction of the magnetic layer can be stabilized.

Next, a method of manufacturing the magnetoresistive effect element shown in FIGS. 1 to 3 will be described with reference to the drawings.

First, as shown in FIG. 4, on the substrate 160,
A multilayer film 161 of the magnetoresistive effect element is formed. The multilayer film 161 may be either the multilayer film of the single spin valve thin film element shown in FIGS. 1 and 2 or the multilayer film of the dual spin valve thin film element shown in FIG.

Further, as in the magnetoresistive effect element shown in FIG. 1, in order to form the antiferromagnetic layer 80 long in the X direction in the drawing,
At the stage of removing the side surface of the multilayer film 161 shown in FIG. 4 by etching, the etching rate and the etching time may be controlled so that the side surface of the antiferromagnetic layer 80 remains without being removed.

When the multilayer film 161 is formed of a single spin valve thin film element or a dual spin valve thin film element, the antiferromagnetic layer forming the multilayer film 161 should be formed of a PtMn alloy. Or X—Mn (where X is Pd, Ir,
Rh or Ru is one or more elements, or Pt—Mn—X ′ (where X ′ is Pd,
Any one of Ir, Rh, Ru, Au, Ag or 2
It is an element of one or more kinds). When the antiferromagnetic layer is formed of the above-mentioned material, it is necessary to perform heat treatment to generate an exchange coupling magnetic field at the interface with the pinned magnetic layer.

As shown in FIG. 18, a conventional (for example, FIG. 19) magnetoresistive effect element in which hard bias layers and electrode layers are formed only on both sides of a multilayer film is used in advance.
The width dimension A of the upper surface of the multilayer film of this magnetoresistive effect element is measured with an optical microscope. Next, the magnetoresistive effect element,
A reproduction output is detected by scanning in the track width direction on a minute track on which a certain signal is recorded, and a region with a width dimension of B on the upper surface that produces a reproduction output of 50% or more of the maximum output is detected. The sensitivity region E and a region having a width dimension C of the upper surface that emits a reproduction output of 50% or less of the maximum output are defined as a dead region D.

Based on the measurement result, the lift-off resist layer 162 is formed on the multilayer film 161 while considering the width dimension C of the dead region D which is known in advance by the microtrack profile method. As shown in FIG.
The resist layer 162 has a cut portion 16 on the lower surface thereof.
2a and 162a are formed, but the cut portion 1
62a and 162a are dead regions D of the multilayer film 161.
The upper surface of the multi-layer film 161 and the sensitivity region E are completely covered with the resist layer 162.

Next, in the step shown in FIG. 5, both sides of the multilayer film 161 are etched by etching. 1 to 3
In the case of manufacturing the magnetoresistive effect element shown in (1), a protective layer is formed on the uppermost layer of the multilayer film 161, and a resist layer 162 is laminated on the protective layer. Further, ions that obliquely enter the portion of the protective layer below the cutouts 162a, 162a of the resist layer 162, that is, the portion of the protective layer where the protective layer and the resist layer 162 are not directly joined. The lower layer of the protective layer is exposed by removing it by milling.

Further, in the step shown in FIG. 6, the multilayer film 1 is
Hard bias layers 163 and 163 are formed on both sides of 61. In the present invention, the hard bias layers 163 and 163 are used.
And the electrode layer 165 formed in the next step are formed by ion beam sputtering,
At least one of the long throw sputtering method and the collimation sputtering method is preferable.

As shown in FIG. 6, in the present invention, the multilayer film 16 is used.
1 formed on the substrate 160, the hard bias layer 16
The hard bias layers 163 and 163 are formed in the vertical direction with respect to the multilayer film 161 by, for example, using an ion beam sputtering method, by placing the target 164 formed with the composition of No. Therefore, the resist layer 1 formed on the multilayer film 161 can be formed.
The hard bias layers 163 and 163 are not formed in the cut portions 162a and 162a of the groove 62. In addition, the multilayer film 1 of the hard bias layers 163 and 163.
Since the vicinity of the surface in contact with 61 is covered with both ends of the resist layer 162, sputtered particles are hard to be laminated. Therefore, the film thickness of the hard bias layers 163 and 163 is thin near the surface in contact with the multilayer film 161, and the upper surfaces of the hard bias layers 163 and 163 are inclined or curved downward in the drawing near the multilayer film 161. . As shown in FIG. 6, a layer 163a having the same composition as the hard bias layers 163 and 163 is also formed on the resist layer 162.

Further, in the present invention, the multilayer film 161 has the structure shown in FIG.
As in the multilayer film of the thin film element shown in FIG. 3, the free magnetic layer is formed by laminating a plurality of soft magnetic thin films having different magnetic moments via a non-magnetic material layer. The multilayer film 161 and the hard bias layer 16
The hard bias layers 163 and 163 are formed such that the magnetic connection surface with the soft magnetic thin film of the free magnetic layer overlaps only the side surface of one soft magnetic thin film. .

The magnetic connection surface between the multilayer film 161 and the hard bias layers 163 and 163 overlaps only the side surface of one soft magnetic thin film among the side surfaces of the plurality of soft magnetic thin films forming the free magnetic layer. By so doing, it is possible to prevent the magnetization direction from being disturbed at both ends of the soft magnetic thin film.

Next, in the step shown in FIG. 7, the multilayer film 16 is formed.
1, the hard bias layers 163, 1
Electrode layers 165 and 165 are formed on the insulating layer 63, and the electrode layers 165 and 165 are formed on the lower surface of the resist layer 162 provided on the multilayer film 161.
A film is formed up to the inside of 62a and 162a.

For example, as shown in FIG. 7, a target 166 formed of the composition of the electrode layer 165 is inclined with respect to the substrate 160 on which the multilayer film 161 is formed, and the target 166 is moved on the substrate 160. While doing so, the electrode layers 165 and 165 are formed on the hard bias layers 163 and 163 by the ion beam sputtering method. At this time, the electrode layers 165 and 165 sputtered from the oblique direction
Is deposited not only on the hard bias layers 163 and 163 but also into the cutouts 162a and 162a of the resist layer 162 formed on the multilayer film 161 to form a film. That is, the electrode layers 165 and 165 formed in the cut portions 162a and 162a are the dead regions D of the multilayer film 161.
A film is formed in a position to cover the top.

In FIG. 7, the substrate 160 is fixed and the target 166 side is moved obliquely with respect to the substrate 160. However, the target 166 is fixed and the substrate 160 is fixed.
The side may be moved obliquely with respect to the target 166. Further, as shown in FIG. 7, electrode layers 165, 16 are formed on the layer 163 a formed on the resist layer 162.
A layer 165a having the same composition as that of No. 5 is formed.

When the protective layer formed on the uppermost layer of the multilayer film 161 is not directly joined to the resist layer 162, the lower layer of the protective layer is exposed. 1 to 3, the electrode layers 165 and 165 are directly connected to the free magnetic layer, the antiferromagnetic layer, or the magnetoresistive effect layer below the protective layer, as in the magnetoresistive effect element shown in FIGS. Is formed.

Then, in the step shown in FIG. 8, the resist layer 162 shown in FIG. 7 is removed by lift-off while using a resist stripping solution, whereby the electrode layers 165 and 165 are formed on the dead regions D of the multilayer film 161. The formed magnetoresistive effect element is completed.

In the step of forming the electrode layers 165 and 165, the angle θ formed by the multilayer film surface 161a and the front end face 165b formed by entering the cut portion 162a of the electrode layer is 20. If it is formed at a temperature of not less than 25 degrees, more preferably not less than 25 degrees, it is possible to prevent the sense current from being shunted and flowing into the dead region to generate noise.

However, in the manufacturing method shown in FIGS. 4 to 8, it is difficult to form a large angle θ between the surface 161a and the front end surface 165b. If the angle θ formed by the surface 161a and the front end surface 165b is too large, the multilayer film 161 and the electrode layers 165, 1 are formed.
When an upper shield layer made of a soft magnetic material is laminated on 65, a short circuit between the electrode layers 165 and 165 and the upper shield layer is likely to occur. Therefore, the angle θ formed by the surface 161a and the front end surface 165b is preferably 60 degrees or less, more preferably 45 degrees or less.

FIG. 9 is a sectional view of another magnetoresistive effect element according to the present invention as viewed from the ABS side.

The magnetoresistive effect element shown in FIG. 9 has the same structure as the magnetoresistive effect element shown in FIG.
An insulating layer 133 made of 1 ₂ O ₃ or the like is laminated, and the front end surfaces 132a and 132a of the electrode layers 132 and 132 are in contact with both side surfaces of the insulating layer 133.

The film constitution and material of the multilayer film 201 are as follows.
All are the same as the magnetoresistive effect element shown in FIG.

Further, the metal film 8 laminated on the width dimension T60 of the antiferromagnetic layer 80 formed extending in the X direction in the figure.
8, 88, hard bias layers 89, 89, intermediate layer 90,
The film structure and material of 90 are the same as those of the magnetoresistive effect element of FIG.

Further, the first pinned magnetic layer 81 and the second pinned magnetic layer 81
The magnetization directions of the pinned magnetic layer 83 are antiparallel to each other in a ferrimagnetic state, and the first pinned magnetic layer 81 and the second pinned magnetic layer 81 are in a ferrimagnetic state.
The other magnetic direction is fixed to the fixed magnetic layer 83, and the fixed magnetic layer P as a whole stabilizes the fixed magnetic direction.

Further, in the magnetoresistive effect element of FIG. 9, the first free magnetic layer 85 and the second free magnetic layer 85 having different magnetic moments are used.
The free magnetic layer 87 is in a ferrimagnetic state in which the magnetization directions are antiparallel, and the first free magnetic layer 85 and the second free magnetic layer 87 are laminated with the nonmagnetic material layer 86 interposed therebetween. The one functions as one free magnetic layer F.

The region of the free magnetic layer F in which the magnetization direction is disturbed near both end portions is a dead region in which the reproducing sensitivity is poor and the magnetoresistive effect cannot be substantially exhibited.

Also in this embodiment, the multilayer film 201 is used.
The sensitivity region E and the dead region D of the are measured by the microtrack profile method, and as shown in FIG.
The area of the multilayer film 201 of 61 is the sensitivity area E, and the area of the width dimension T62 is the dead area D.

In the sensitivity region E, the magnetization direction of the pinned magnetic layer P is properly pinned in the direction parallel to the Y direction in the drawing, and the magnetization of the free magnetic layer F is properly aligned in the X direction in the drawing. The magnetizations of the fixed magnetic layer P and the free magnetic layer F have an orthogonal relationship. Then, the magnetization of the free magnetic layer F sensitively changes with respect to the external magnetic field from the recording medium, and the electric resistance changes due to the change in the magnetization direction and the fixed magnetization direction of the fixed magnetic layer P. The leakage magnetic field from the recording medium is detected by the voltage change based on the change of the resistance value.

The electrode layers 132, 132 formed on both sides of the multilayer film 201 are formed so as to extend onto the multilayer film 201, and the electrode layers 132, 132 of the multilayer film 201 without the electrode layers 132, 132 are formed. The width dimension of the upper surface is the optical track width dimension O-Tw.

The magnetic track width M-Tw determined by the width of the sensitivity region E whose upper surface is not covered with the electrode layers 132, 132 is the same as the width T6 of the sensitivity region E.
It is 1.

In this embodiment, the electrode layers 132, 132 formed on the multilayer film 201 completely cover the dead region D, and the optical track width dimension O-Tw and the magnetic track width dimension M-Tw ( = Width dimension of the sensitivity region E) is formed with substantially the same width dimension.

However, the electrode layers 132, 132 formed on the multilayer film 201 may be formed shorter than that without completely covering the dead region D. At this time, the optical track width dimension O-Tw is formed larger than the magnetic track width dimension M-Tw.

Therefore, in the present invention, the electrode layer 1 is formed in the multilayer film 201 without the hard bias layers 89, 89 interposed therebetween.
The ratio of the sense currents from 32 and 132 can be increased.

In addition, the electrode layers 132 and 132 are not in the dead area D.
When it is extended and formed, the sense current is applied to the dead region D.
It is possible to suppress the occurrence of noise flowing into the.

Further, in FIG. 9, the protective layer 15 is formed on a portion of the multilayer film 201 which is not joined to the electrode layers 132, 132, and the insulating layer 1 is formed on the protective layer 15.
33 is formed. The electrode layers 132, 132 are
The second free magnetic layer 8 directly without the protection layer 15.
It is joined with 7.

Therefore, the electrode layer 1 is formed on the protective layer 15.
The electric resistance can be lowered and the characteristics of the magnetoresistive effect element can be improved as compared with the case where 32 and 132 are stacked.

When the magnetoresistive effect element shown in FIG. 9 is formed by a manufacturing method described later, it is in contact with both side surfaces of the insulating layer 133 of the electrode layer 132 extending over the dead region of the multilayer film 201. The angle θ21 formed by the front end surface 132a and the surface 87a of the second free magnetic layer 87 can be set to 60 degrees or more, further 90 degrees or more. Therefore, a constant amount of sense current can always flow to the tip of the electrode layer 132. That is, it is possible to more effectively suppress that the sense current is shunted to flow into the dead region to generate noise, as compared with the magnetoresistive effect element shown in FIG.

In the magnetoresistive effect element shown in FIG. 9, the position of the insulating layer 133 on the multilayer film 201 can be accurately set by using the manufacturing method described later, so that the electrode layers 132, 132 are formed. Can be prevented from extending beyond the dead region, and the region where the magnetoresistive effect element can actually detect the magnetic field can be prevented from becoming narrow.

Note that, as shown in FIG. 9, the width dimension T63 of the electrode layer 132 extended and formed on the dead region D of the multilayer film 201 is specifically larger than 0 μm and 0.08 μm.
The following is preferable. The width dimension T63 of the electrode layer 132 is more preferably 0.05 μm or more and 0.08 μm or less.

Further, in FIG. 9, magnetic connection planes M, M between the multilayer film 201 and the hard bias layers 89, 89.
However, of the side surfaces of the first free magnetic layer 85 and the second free magnetic layer 87, only the side surface of the first free magnetic layer 85 overlaps.

By forming the magnetoresistive effect element of FIG. 9 using a manufacturing method described later, the side surface of the multilayer film 201 of the magnetoresistive effect element of FIG. 9 and the insulating layer 133 are formed.
The sides of are parallel.

FIG. 10 is a sectional view of another magnetoresistive effect element according to the present invention as viewed from the ABS side.

The magnetoresistive effect element of FIG. 10 has the same structure as the magnetoresistive effect element shown in FIG.
An insulating layer 135 made of Al ₂ O ₃ or the like is laminated, and front end surfaces 134a and 134a of the electrode layers 134 and 134 are in contact with both side surfaces of the insulating layer 135.

The film structure and material of the multilayer film 202 are as follows.
This is the same as the magnetoresistive effect element shown in FIG. However, in FIG. 10, the protective layer 15 is not formed on the uppermost layer of the multilayer film 202.

Also, the metal film 8 laminated on the base film 10
8, 88, hard bias layers 89, 89, intermediate layer 90,
The film structure and material of 90 are the same as those of the magnetoresistive effect element of FIG.

The first pinned magnetic layer 81 and the second pinned magnetic layer 81
The magnetization directions of the pinned magnetic layer 83 are antiparallel to each other in a ferrimagnetic state, and the first pinned magnetic layer 81 and the second pinned magnetic layer 81 are in a ferrimagnetic state.
The other magnetic direction is fixed to the fixed magnetic layer 83, and the fixed magnetic layer P as a whole stabilizes the fixed magnetic direction.

The magnetoresistive effect element of FIG. 10 is in a ferrimagnetic state in which the magnetization directions of the first free magnetic layer 85 and the second free magnetic layer 87 having different magnetic moments are antiparallel, and The first free magnetic layer 85
And the second free magnetic layer 87 is the non-magnetic material layer 86.
The layers laminated via the above function as one free magnetic layer F.

The region of the free magnetic layer F in which the magnetization direction is disturbed near both end portions is a dead region where the reproducing sensitivity is poor and the magnetoresistive effect cannot be substantially exhibited.

Also in this embodiment, the multilayer film 202 is used.
The sensitivity region E and the insensitive region D are measured by the microtrack profile method. As shown in FIG. 10, the region of the multilayer film 202 having the width dimension T64 is the sensitivity region E, and the region of the width dimension T65 is the dead region D. Is.

In the sensitivity region E, the magnetization direction of the pinned magnetic layer P is properly pinned in the direction parallel to the Y direction in the drawing, and the magnetization of the free magnetic layer F is properly aligned in the X direction in the drawing. The magnetizations of the fixed magnetic layer P and the free magnetic layer F have an orthogonal relationship. Then, the magnetization of the free magnetic layer F sensitively changes with respect to the external magnetic field from the recording medium, and the electric resistance changes due to the change in the magnetization direction and the fixed magnetization direction of the fixed magnetic layer P. The leakage magnetic field from the recording medium is detected by the voltage change based on the change of the resistance value.

The electrode layers 134 and 134 formed on both sides of the multilayer film 202 are formed so as to extend onto the multilayer film 202, and the electrode layers 134 and 134 of the multilayer film 202 on which the electrode layers 134 and 134 are not formed are formed. The width dimension of the upper surface is the optical track width dimension O-Tw.

The magnetic track width dimension M-Tw, which is determined by the width dimension of the sensitivity region E whose upper surface is not covered with the electrode layers 134, 134, is the same width dimension T6 as the sensitivity region E.
It is 4.

In this embodiment, the electrode layers 134 and 134 formed on the multilayer film 202 completely cover the dead region D, and the optical track width dimension O-Tw and the magnetic track width dimension M-Tw ( = Width dimension of the sensitivity region E) is formed with substantially the same width dimension.

However, the electrode layers 134 and 134 formed on the multilayer film 202 may be formed shorter than that without completely covering the dead region D. At this time, the optical track width dimension O-Tw is formed larger than the magnetic track width dimension M-Tw.

Therefore, in the present invention, the electrode layer 1 is formed in the multilayer film 202 without the hard bias layers 89, 89 interposed therebetween.
It is possible to increase the ratio of flowing the sense current from 34 and 134.

In addition, the electrode layers 134 and 134 are not in the dead area D.
When it is extended and formed, the sense current is applied to the dead region D.
It is possible to suppress the occurrence of noise flowing into the.

In FIG. 10, the protective layer 15 is not formed on the uppermost layer of the multilayer film 202, and the antiferromagnetic layer 8 is not formed.
The insulating layer 133 is formed directly on the insulating layer 133, and the insulating layer 133 also functions as a protective layer for preventing oxidation.
The electrode layers 134 and 134 are directly bonded to the antiferromagnetic layer 80.

Therefore, the electrode layer 1 is formed on the protective layer 15.
The electric resistance can be lowered and the characteristics of the magnetoresistive effect element can be improved as compared with the case where 34 and 134 are laminated.

When the magnetoresistive effect element of FIG. 10 is formed by using a manufacturing method described later, the insulating layer 135 of the electrode layer 134 extending over the dead region of the multilayer film 202.
The angle θ22 formed by the front end face 134a which is in contact with both side face portions and the surface 80a of the antiferromagnetic layer 80 can be 60 degrees or more, and further 90 degrees or more. Therefore, a constant amount of sense current can always flow to the tip of the electrode layer 134. That is, the sense current is shunted to flow into the dead area to generate noise.
It can be suppressed more effectively than the magnetoresistive effect element shown in FIG.

In the magnetoresistive effect element of FIG. 10, the insulating layer 135 is formed by using the manufacturing method described later.
Since the position of the electrode on the multilayer film 202 can be set accurately, it is possible to prevent the electrode layer 134 from extending beyond the dead region, and the magnetoresistive effect element can actually detect the magnetic field. It is possible to prevent the area from becoming narrow.

As shown in FIG. 10, the width dimension T66 of the electrode layer 134 formed on the dead region D of the multilayer film 202 is specifically greater than 0 μm and 0.08 μm.
It is preferably m or less. The width dimension T66 of the electrode layer 134 is more preferably 0.05 μm or more and 0.08 μm or less.

Further, in FIG. 10, magnetic connection planes M, M between the multilayer film 202 and the hard bias layers 89, 89.
However, of the side surfaces of the first free magnetic layer 85 and the second free magnetic layer 87, only the side surface of the second free magnetic layer 87 overlaps.

By forming the magnetoresistive effect element of FIG. 10 using a manufacturing method described later, the side surface of the multilayer film 202 of the magnetoresistive effect element of FIG. 10 and the insulating layer 1 are formed.
The side surfaces of 35 are parallel.

FIG. 11 is a sectional view of another magnetoresistive effect element according to the present invention as seen from the ABS side.

The magnetoresistive effect element of FIG. 11 has the same structure as the magnetoresistive effect element shown in FIG.
An insulating layer 137 made of Al ₂ O ₃ or the like is laminated, and the front end surfaces 136a and 136a of the electrode layers 136 and 136 are in contact with both side surfaces of the insulating layer 137.

The film structure and material of the multilayer film 203 are as follows.
This is the same as the magnetoresistive effect element shown in FIG. However, in FIG. 11, the protective layer 15 is not formed on the uppermost layer of the multilayer film.

The films of the metal films 113, 113, the hard bias layers 114, 114, and the intermediate layers 115, 115 laminated on the width dimension T67 of the antiferromagnetic layer 100 formed by extending in the X direction in the figure. The structure and material are the same as those of the magnetoresistive effect element shown in FIG.

Further, the magnetization directions of the first pinned magnetic layer 103 and the second pinned magnetic layer 101 are antiparallel to each other in a ferrimagnetic state, and the first pinned magnetic layer 103 and the second pinned magnetic layer 103 are in the antiferromagnetic state. The layer 101 fixes the other magnetization direction to each other, and stabilizes the magnetization direction of the pinned magnetic layer P _{1 in} a fixed direction as a whole. Furthermore, the third pinned magnetic layer 1
09 and the magnetization direction of the fourth pinned magnetic layer 111 are also antiparallel to each other in a ferrimagnetic state.

The magnetoresistive effect element of FIG. 11 is in a ferrimagnetic state in which the magnetization directions of the first free magnetic layer 105 and the second free magnetic layer 107 having different magnetic moments are antiparallel, and The first free magnetic layer 105 and the second free magnetic layer 107, which are stacked with the non-magnetic material layer 106 in between, function as one free magnetic layer F.

The region of the free magnetic layer F in which the magnetization direction is disturbed near both end portions is a dead region in which the reproducing sensitivity is poor and the magnetoresistive effect cannot be substantially exerted.

Also in this embodiment, the multilayer film 203 is used.
The sensitivity region E and the insensitive region D are measured by the microtrack profile method. As shown in FIG. 11, the region of the multilayer film 203 having the width T68 is the sensitivity region E, and the region of the width T69 is the dead region D. Is.

In the sensitivity region E, the pinned magnetic layers P ₁ , P ₂
Is properly pinned in a direction parallel to the Y direction in the figure, and the magnetization of the free magnetic layer F is properly aligned in the X direction in the figure, and the pinned magnetic layers P ₁ and P ₂ and the free magnetic layer F are aligned.
Are in an orthogonal relationship. Then, the magnetization of the free magnetic layer F sensitively changes with respect to the external magnetic field from the recording medium, and the electric resistance changes due to the change in the magnetization direction and the fixed magnetization direction of the fixed magnetic layers P ₁ and P _2. However, the leakage magnetic field from the recording medium is detected by the voltage change based on the change of the electric resistance value.

The electrode layers 136 and 136 formed on both sides of the multilayer film 203 are formed so as to extend onto the multilayer film 203, and the electrode layers 136 and 136 of the multilayer film 203 on which the electrode layers 136 and 136 are not formed are formed. The width dimension of the upper surface is the optical track width dimension O-Tw.

The magnetic track width dimension M-Tw, which is determined by the width dimension of the sensitivity region E whose upper surface is not covered with the electrode layers 136 and 136, is the same width dimension T6 as the sensitivity region E.
8

In this embodiment, the electrode layers 136 and 136 formed on the multilayer film 203 completely cover the dead region D, and the optical track width dimension O-Tw and the magnetic track width dimension M-Tw ( = Width dimension of the sensitivity region E) is formed with substantially the same width dimension.

However, the electrode layers 136 and 136 formed on the multilayer film 203 may be formed shorter than that without completely covering the dead region D. At this time, the optical track width dimension O-Tw is formed larger than the magnetic track width dimension M-Tw.

Accordingly, in the present invention, the electrode layer 13 is provided in the multilayer film 203 without the hard bias layer 114.
It is possible to increase the ratio of flowing the sense current from 6, 136.

In addition, the electrode layers 136 and 136 are insensitive areas D.
When it is extended and formed, the sense current is applied to the dead region D.
It is possible to suppress the occurrence of noise flowing into the.

In FIG. 11, the protective layer 15 is not formed on the uppermost layer of the multilayer film 203, and the antiferromagnetic layer 1 is not formed.
The insulating layer 137 is directly formed on the layer 12, and the insulating layer 137 also serves as a protective layer for preventing oxidation. The electrode layers 136 and 136 are directly bonded to the antiferromagnetic layer 112.

Therefore, the electrode layer 1 is formed on the protective layer 15.
The electric resistance can be lowered and the characteristics of the magnetoresistive effect element can be improved as compared with the case where 36 and 136 are stacked.

When the magnetoresistive effect element of FIG. 11 is formed by the manufacturing method described later, the insulating layer 137 of the electrode layer 136 extending over the dead region of the multilayer film 203.
The angle θ23 formed by the front end surface 136a in contact with both side surface portions of the and the surface 112a of the antiferromagnetic layer 112 can be set to 60 degrees or more, further 90 degrees or more. Therefore, a constant amount of sense current can always flow to the tip of the electrode layer 136. That is, it is possible to more effectively suppress that the sense current is shunted and flows into the dead region to generate noise, as compared with the magnetoresistive effect element shown in FIG.

On the other hand, in the magnetoresistive effect element of FIG. 11, the insulating layer 137 is formed by using the manufacturing method described later.
Since the position of the electrode on the multilayer film 203 can be set accurately, it is possible to prevent the electrode layers 136 and 136 from extending beyond the dead region, and the magnetoresistive effect element actually generates a magnetic field. It is possible to prevent the detectable area from becoming narrow.

As shown in FIG. 11, the width dimension T70 of the electrode layer 136 formed on the dead region D of the multilayer film 203 is specifically larger than 0 μm and 0.08 μm.
It is preferably m or less. The width dimension T70 of the electrode layer 136 is more preferably 0.05 μm or more and 0.08 μm or less.

Further, in FIG. 11, the magnetic connection surfaces M, M between the multilayer film 203 and the hard bias layers 114, 114 are the side surfaces of the first free magnetic layer 105 and the second free magnetic layer 107. Of which, the first free magnetic layer 1
It only overlaps with the side of 05.

By forming the magnetoresistive effect element of FIG. 11 by using a manufacturing method described later, the side surface of the multilayer film 203 of the magnetoresistive effect element of FIG. 11 and the insulating layer 1 are formed.
The side surfaces of 37 are parallel.

Further, since the magnetoresistive effect element shown in FIGS. 9 to 11 has the insulating layer formed between the electrode layers, the upper surface of the magnetoresistive element becomes gentle, and the protective layer, the free magnetic layer, or the antiferromagnetic layer is formed. Even if the angle formed by the surface of the electrode and the front end face of the electrode layer is large, when the upper shield layer made of a soft magnetic material is laminated on the multilayer film and the electrode layer, the electrode layer and the upper shield are formed. A short circuit with the layer is less likely to occur.

Next, a method of manufacturing the magnetoresistive effect element shown in FIGS. 9 to 11 will be described with reference to the drawings.

First, as shown in FIG. 12, a multilayer film 151 of a magnetoresistive effect element is formed on a substrate 150, and an insulating layer 152 is formed on the multilayer film 151 using Al ₂ O ₃ or the like. To do. The multilayer film 151 may be either the single spin valve thin film element multilayer film shown in FIGS. 9 and 10 or the dual spin valve thin film element multilayer film shown in FIG. 11.

To form the antiferromagnetic layer 80 long in the X direction as shown in the spin-valve type thin film element shown in FIG. 9, side surfaces of the multilayer film 151 and the insulating layer 152 shown in FIG. 12 are removed by etching. At the stage, the etching rate and etching time may be controlled so that the side surface of the antiferromagnetic layer 80 or 100 remains without being scraped off.

When the multilayer film 151 is formed of a single spin valve thin film element or a dual spin valve thin film element, the antiferromagnetic layer forming the multilayer film 151 should be formed of PtMn alloy. Or X—Mn (where X is Pd, Ir,
Rh or Ru is one or more elements, or Pt—Mn—X ′ (where X ′ is Pd,
Any one of Ir, Rh, Ru, Au, Ag or 2
It is an element of one or more kinds). When the antiferromagnetic layer is formed of the above-mentioned material, it is necessary to perform heat treatment to generate an exchange coupling magnetic field at the interface with the pinned magnetic layer.

In advance, as shown in FIG. 18, a conventional (for example, FIG. 19) magnetoresistive effect element in which hard bias layers and electrode layers are formed only on both sides of the multilayer film is used.
The width dimension A of the upper surface of the multilayer film of this magnetoresistive effect element is measured with an optical microscope. Next, the magnetoresistive effect element,
A reproduction output is detected by scanning in the track width direction on a minute track on which a certain signal is recorded, and a region with a width dimension of B on the upper surface that produces a reproduction output of 50% or more of the maximum output is detected. The sensitivity region E and a region having a width dimension C of the upper surface that emits a reproduction output of 50% or less of the maximum output are defined as a dead region D.

Based on the measurement result, the lift-off resist layer 153 is formed on the insulating layer 152, taking into consideration the width dimension C of the dead region D which is known in advance by the microtrack profile method.

As shown in FIG. 12, the resist layer 15 is formed.
3, cutouts 153a, 153a are formed on the lower surface thereof. The resist layer 153 serves as a mask when the insulating layer 152 is etched in a later step. Insulation layer 1
After etching 52, the resist layer 153 is adjusted and laminated so that the bottom surface of the insulating layer 152 can completely cover the sensitive region E of the multilayer film 151. The cut portions 153a, 153a are formed mainly on the dead region D of the multilayer film 151. When the side surface of the resist layer 153 becomes an inclined surface after etching, the cut portions 153a, 153a are taken into consideration in consideration of the inclined surface. May be extended slightly above the sensitivity region E.

Next, in the step shown in FIG. 13, both sides of the multilayer film 151 and the insulating layer 152 are etched by etching.

Next, in the step shown in FIG. 14, only the insulating layer 152 made of Al ₂ O ₃ is etched with an alkaline solution to expose the dead region D of the multilayer film 151. At this time, each layer constituting the multilayer film 151 is not eluted with the alkaline solution. In the state of FIG. 14, the bottom surface of the insulating layer 152 completely covers the sensitivity region E of the multilayer film 151.

When the insulating layer 152 made of Al ₂ O ₃ is etched with an alkaline solution, the side surface of the insulating layer 152 is etched while keeping the side surface parallel to the side surface of the multilayer film 151. The side surface of the layer 152 and the side surface of the multilayer film 151 are parallel to each other.

When manufacturing the magnetoresistive effect element shown in FIG. 9, a protective layer is formed on the uppermost layer of the multilayer film 151, and the insulating layer 152 and the resist layer 153 are formed on the protective layer. Are sequentially laminated. Further, after the step of FIG. 14, the cut portions 153a, 15a of the resist layer 153 are formed.
The portion of the protective layer that is below 3a and is not covered by the insulating layer 152 is removed by ion milling that is obliquely incident to expose the lower layer of the protective layer.

Further, in the step shown in FIG. 15, hard bias layers 154 and 154 are formed on both sides of the multilayer film 151. In the present invention, the hard bias layers 154, 15
The sputtering method used in the film formation of No. 4 and the film formation of the electrode layer 156 performed in the next step is at least one of an ion beam sputtering method, a long throw sputtering method, and a collimation sputtering method. Is preferred.

As shown in FIG. 15, in the present invention, the multilayer film 1
The substrate 150 on which 51 is formed is attached to the hard bias layer 15
The hard bias layers 154 and 154 are formed in the vertical direction with respect to the multilayer film 151 by, for example, using an ion beam sputtering method, by arranging the hard bias layers 154 and 154 in the vertical direction with respect to the target 155 formed with the composition of 4,154. You can The hard bias layers 154 and 154 are the multilayer film 15.
Since the vicinity of the surface in contact with 1 is covered by both ends of the resist layer 153, sputtered particles are hard to be laminated.
Therefore, the multilayer film 15 of the hard bias layers 154 and 154 is
The thickness of the hard bias layers 154 and 154 is thin near the surface in contact with 1, and the upper surfaces of the hard bias layers 154 and 154 are inclined or curved downward in the drawing near the multilayer film 151. As shown in FIG. 15, a layer 154a having the same composition as the hard bias layer 154 is also formed on the resist layer 153.

In the present invention, the multi-layer film 151 has the structure shown in FIG.
11 to 11, the free magnetic layer is formed by laminating a plurality of soft magnetic thin films having different magnetic moments via a non-magnetic material layer. The multilayer film 151 and the hard bias layer 15
The hard bias layers 154 and 154 are formed such that a magnetic connection surface with the soft magnetic thin film forming the free magnetic layer overlaps only a side surface of one soft magnetic thin film. .

The magnetic connection surface between the multilayer film 151 and the hard bias layers 154 and 154 overlaps only the side surface of one soft magnetic thin film among the side surfaces of the plurality of soft magnetic thin films forming the free magnetic layer. By so doing, it is possible to prevent the magnetization direction from being disturbed at both ends of the soft magnetic thin film.

Next, in the step shown in FIG. 16, the multilayer film 1
The hard bias layers 154,
Electrode layers 156 and 156 are formed on 154. At this time, the electrode layers 156 and 156 are formed in the cutouts 153a and 153a formed on the lower surface of the resist layer 153 provided on the multilayer film 151. Form a film.

For example, as shown in FIG. 16, a multilayer film 151
The target 157 formed of the composition of the electrode layer 156 is obliquely tilted with respect to the substrate 150 on which the electrodes are formed, and the target 157 is moved on the substrate 150 while the electrode layers 156 and 156 are formed by the ion beam sputtering method.
Are formed on the hard bias layers 154 and 154. At this time, the electrode layer 156 that is obliquely sputtered is not only on the hard bias layers 154 and 154 but also on the insulating layer 1.
Notch 1 of resist layer 153 formed on 52
A film is also formed by penetrating into 53a.

That is, the cut portions 153a, 15
The electrode layers 156 and 156 formed in 3a are the multilayer film 1
A film is formed at a position covering the dead region 51 of 51.

Further, the front end surfaces 156b of the electrode layers 156 and 156 are in contact with both side surfaces of the insulating layer 152.

In FIG. 16, the substrate 150 is fixed and the target 157 side is moved obliquely with respect to the substrate 150. However, the target 157 is fixed and the substrate 15 is fixed.
The 0 side may be moved obliquely with respect to the target 157. Further, as shown in FIG.
A layer 156a having the same composition as the electrode layer 156 is formed on the layer 154a formed on the third layer.

When the lower layer of the protective layer formed on the uppermost layer of the multilayer film 151 is exposed, the electrode layer 15 is formed as in the thin film magnetic element shown in FIG.
6, 156 are formed on the free magnetic layer below the protective layer.

Then, in the step shown in FIG. 17, the resist layer 153 shown in FIG. 16 is removed by lift-off while using a resist stripping solution, so that the electrode layers 156 and 156 are formed on the dead region D of the multilayer film 151. A magnetoresistive effect element in which the insulating layer 152 is formed between the electrode layers 156 and 156 is completed.

In the step of forming the electrode layers 156 and 156, the front end face of the electrode layer 156 extended over the dead region D of the multilayer film 151 is in contact with both side faces of the insulating layer 152. The angle θ formed by 156b and the surface 151a of the multilayer film 151 is 60 degrees or more, and further,
It can be 90 degrees or more. Therefore, the electrode layer 1
A constant amount of sense current can always flow up to the tip of 56. That is, it is possible to manufacture the magnetoresistive effect element capable of suppressing the generation of noise by flowing the sense current into the dead region to generate noise more effectively than the magnetoresistive effect element shown in FIGS.

Also, the multi-layer film 15 of the insulating layer 152.
Since the position on 1 can be set accurately, it is possible to prevent the electrode layers 156 and 156 from extending beyond the insensitive region, and there is a region where the magnetoresistive effect element can actually detect the magnetic field. It can be prevented from becoming narrow.

[0258]

According to the present invention described in detail above, since the bias layer is magnetically connected to only one soft magnetic film of the plurality of soft magnetic thin films forming the free magnetic layer, the soft magnetic Disturbance of the magnetization direction can be suppressed at both ends of the thin film,
As a whole, the magnetization direction of the free magnetic layer can be stabilized in a fixed direction. Therefore, it is possible to effectively improve the reproduction characteristics.

The electrode layers formed on both sides of the multilayer film are
By forming the multi-layer film to extend over the sensitivity region formed near both sides of the multi-layer film, which has a poor magnetoresistive effect and does not substantially have a reproducing function, the sense current from the electrode layer is hardened. It is easy to flow into the multilayer film without passing through the bias layer, and moreover, the junction area with the multilayer film can be increased, so that the DC resistance can be reduced and the reproducing characteristic can be improved.

Further, in the present invention, it is possible to surely and easily form the electrode layer on the insensitive region of the multilayer film by using the resist layer for lift-off and by the ion beam sputtering method or the like.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing the structure of a magnetoresistive effect element according to a first embodiment of the present invention,

FIG. 2 is a partial cross-sectional view showing the structure of a magnetoresistive effect element according to a second embodiment of the present invention,

FIG. 3 is a partial cross-sectional view showing the structure of a magnetoresistive effect element according to a third embodiment of the present invention,

FIG. 4 is a process chart showing a method of manufacturing a magnetoresistive effect element according to the present invention,

5 is a process chart performed after the step of FIG. 4,

FIG. 6 is a process chart that follows the process of FIG. 5;

FIG. 7 is a process chart that follows the process of FIG. 6;

FIG. 8 is a process chart performed after the step of FIG.

FIG. 9 is a partial cross-sectional view showing the structure of a magnetoresistive effect element according to a fourth embodiment of the present invention,

FIG. 10 is a partial cross-sectional view showing the structure of a magnetoresistive effect element according to a fifth embodiment of the present invention,

FIG. 11 is a partial cross-sectional view showing the structure of a magnetoresistive effect element according to a sixth embodiment of the present invention,

FIG. 12 is a process chart showing a method of manufacturing a magnetoresistive effect element according to the present invention,

FIG. 13 is a process chart that follows the process of FIG. 12;

FIG. 14 is a process chart performed after the step of FIG. 13;

FIG. 15 is a process chart performed after the step of FIG. 14;

16 is a process chart performed after the step of FIG. 15,

FIG. 17 is a process chart that follows the process of FIG. 16;

FIG. 18 is a measurement diagram showing a method of measuring a sensitivity region and a dead region D in a multilayer film of a magnetoresistive effect element;

FIG. 19 is a partial cross-sectional view showing the structure of a conventional magnetoresistive effect element,

[Explanation of symbols]

80 Antiferromagnetic layer 84 Non-magnetic conductive layer 85, 105 first free magnetic layer 86, 106 non-magnetic material layer 87, 107 second free magnetic layer 89, 114 Hard bias layer 91, 116 Electrode layer 133 insulating layer 153, 162 Lift-off resist layer 153a, 162a Notches 155,157,164,166 Target 201, 202, 203 Multilayer film D dead zone E sensitivity range M-Tw Magnetic track width dimension O-Tw Optical track width dimension P fixed magnetic layer F-free magnetic layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Daigo Aoki             1-7 Aki, Otsuka-cho, Yukiya, Ota-ku, Tokyo             Su Electric Co., Ltd. (72) Inventor Yoshihiko Kakihara             1-7 Aki, Otsuka-cho, Yukiya, Ota-ku, Tokyo             Su Electric Co., Ltd. F term (reference) 2G017 AA01 AC09 AD55 AD65                 5D034 BA03 BA08                 5E049 AA10 BA12 BA16

Claims (12)

[Claims] 1. An antiferromagnetic layer, a pinned magnetic layer formed in contact with the antiferromagnetic layer and having a magnetization direction pinned by an exchange anisotropic magnetic field with the antiferromagnetic layer, and the pinned magnetic layer. A multilayer film having a free magnetic layer formed via a non-magnetic conductive layer on both sides, and a magnetization direction of the free magnetic layer formed on both sides of the multilayer film in a direction crossing the magnetization direction of the pinned magnetic layer. A magnetoresistive effect element comprising: a pair of aligned bias layers; and a pair of conductive layers formed on the bias layers, the fixed magnetic layer, the nonmagnetic conductive layer, and the free magnetic layer providing a detection current. The magnetic layer is a ferrimagnetic state in which a plurality of soft magnetic thin films are laminated via a nonmagnetic material layer, and the magnetization directions of the soft magnetic thin films adjacent to each other via the nonmagnetic material layer are antiparallel, Magnetization between the multilayer film and the bias layer Magnetic sensor, characterized in that connection faces of the side surfaces of the plurality of soft magnetic thin films constituting the free magnetic layer, overlaps the side surface of one of the soft magnetic thin film only. 2. A free magnetic layer, a nonmagnetic conductive layer formed above and below the free magnetic layer, and a nonmagnetic conductive layer formed on one nonmagnetic conductive layer and below the other nonmagnetic conductive layer. A multilayer film having a pinned magnetic layer that is pinned and an antiferromagnetic layer formed on one pinned magnetic layer and below the other pinned magnetic layer; and A pair of bias layers that align the magnetization direction of the magnetic layer in a direction intersecting with the magnetization direction of the pinned magnetic layer, and provide a detection current to the pinned magnetic layer, the nonmagnetic conductive layer, and the free magnetic layer formed on the bias layers. In the magnetoresistive effect element including a pair of conductive layers, the free magnetic layer is formed by stacking a plurality of soft magnetic thin films via a nonmagnetic material layer, and adjoining the nonmagnetic material layer via the nonmagnetic material layer. The magnetization directions of the soft magnetic thin film become antiparallel The magnetically connecting surface between the multilayer film and the bias layer overlaps only one side surface of one soft magnetic thin film among the side surfaces of the plurality of soft magnetic thin films forming the free magnetic layer. A magnetic detection element characterized by the above. 3. The pinned magnetic layer is formed by stacking a plurality of soft magnetic thin films with a nonmagnetic material layer interposed therebetween, and the magnetization directions of the soft magnetic thin films adjacent to each other with the nonmagnetic material layer interposed are antiparallel. The magnetoresistive effect element according to claim 1, which is in a ferrimagnetic state. 4. The nonmagnetic material layer comprises Ru, Rh, I
4. The magnetoresistive effect element according to claim 1, wherein the magnetoresistive effect element is formed of an alloy of one or more of r, Cr, Re, and Cu. 5. The magnetoresistive element according to claim 1, wherein the antiferromagnetic layer is made of a PtMn alloy. 6. The antiferromagnetic layer comprises X—Mn (where X is Mn).
Is an alloy of one or more of Pd, Ir, Rh, and Ru). The magnetoresistive effect element according to claim 1, wherein the magnetoresistive element is formed of an alloy. 7. The antiferromagnetic layer is Pt—Mn—X ′.
(However, X'is Pd, Ir, Rh, Ru, Au, Ag
5. The magnetoresistive effect element according to claim 1, wherein the magnetoresistive effect element is formed of an alloy of any one of the above or two or more elements. 8. The multi-layer film is formed on both sides of the central sensitivity region, which is excellent in reproducing sensitivity and can substantially exhibit a magnetoresistive effect, and has poor reproducing sensitivity and is substantially a magnetoresistive film. The dead layer which cannot exert an effect, and the electrode layers formed on both sides of the multilayer film are formed to extend onto the dead region of the multilayer film. The magnetoresistive effect element according to any one of the claims. 9. The sensitivity region of the multilayer film is obtained when a magnetoresistive element having electrode layers formed only on both sides of the multilayer film is scanned in a track width direction on a minute track on which a certain signal is recorded. , The maximum output of the obtained playback output is 50
9. An area where an output of not less than% is obtained, and dead areas of the multilayer film are defined as areas on both sides of the sensitivity area where the output is 50% or less of the maximum output. Magnetoresistive effect element. 10. The sensitivity region of the multilayer film is formed with the same width dimension as the optical track width dimension O-Tw.
Alternatively, the magnetoresistive element according to item 9. 11. The magnetoresistive effect element according to claim 8, wherein a width dimension of each electrode layer in a portion extended and formed on the multilayer film is in a range of more than 0 μm and 0.08 μm. . 12. The magnetoresistive effect element according to claim 11, wherein a width dimension of each electrode layer in a portion extending and formed on the multilayer film is 0.05 μm or more.