JP3688229B2 - Magnetic sensing element and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic detection element and a manufacturing method thereof.
[0002]
[Prior art and its problems]
A magnetic sensing element, such as a spin valve magnetoresistive effect element, includes a bias layer on both sides of a track region of a multilayer film having an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer. And an electrode layer. In this spin-valve magnetoresistive element, the magnetization of the pinned magnetic layer and the magnetization of the free magnetic layer are set in a substantially intersecting direction, and the magnetization of the free magnetic layer fluctuates due to leakage magnetic flux from the recording medium. As a result, the electrical resistance changes depending on the magnetization relationship with the pinned magnetic layer, thereby regenerating the leakage magnetic field.
[0003]
FIG. 14 is a cross-sectional view of a conventional spin valve magnetoresistive effect element as viewed from the facing surface (ABS surface) side of the recording medium. In the spin valve magnetoresistive effect element (first conventional example) shown in the figure, an antiferromagnetic layer 102 formed on an underlayer 101 is formed long in the track width Tw direction (X direction) shown in the figure. At the center of the width region (hereinafter sometimes referred to as the center in the X direction for convenience), the antiferromagnetic layer 102 is formed so as to protrude by the height dimension d1. A pinned magnetic layer 103, a nonmagnetic conductive layer 104, a free magnetic layer 105, and a protective layer 106 are formed on the protruding antiferromagnetic layer 102, and a laminate from the base layer 101 to the protective layer 106 is formed. A multilayer film 107 is formed.
[0004]
In the spin valve thin film element of the first conventional example, the antiferromagnetic layer 102 is formed of a Pt—Mn (platinum-manganese) alloy film or the like. The magnetization of the pinned magnetic layer 103 is pinned in the height direction (Y direction in the drawing) by an exchange coupling magnetic field generated at the interface with the antiferromagnetic layer 102. The fixed magnetic layer 103 and the free magnetic layer 105 are made of a Ni—Fe (nickel-iron) alloy, Co (cobalt), a Fe—Co (iron-cobalt) alloy, a Fe—Co—Ni alloy, or the like. The nonmagnetic conductive layer 104 is formed of a nonmagnetic conductive material having a low electrical resistance such as Cu (copper). The Z direction is the stacking direction of the thin films.
[0005]
A bias underlayer 108 serving as a buffer film and an alignment film formed of Cr (chromium) or the like is formed on the antiferromagnetic layer 102 formed to extend in the X direction in the drawing and on the side surface of the multilayer film 107. A hard bias layer (hard magnetic layer) 109 made of, for example, a Co—Pt (cobalt-platinum) alloy or the like is laminated on the bias underlayer 108.
[0006]
The hard bias layer 109 is magnetized in the X direction (track width direction) in the drawing, and the magnetization of the free magnetic layer 105 is aligned in the same X direction by a bias magnetic field from the hard bias layer 109 in the X direction. It has been. The bias underlayer 108 increases a bias magnetic field generated from the hard bias layer 109.
[0007]
Further, an electrode layer 111 made of Cr (chromium), Au (gold), Ta (tantalum), W (tungsten) or the like is laminated on the hard bias layer 109.
[0008]
As described above, the presence of the bias underlayer 108 provided on the side surfaces of the antiferromagnetic layer 102 and the multilayer film 107 can increase the bias magnetic field generated from the hard bias layer 109. By the way, the hard bias layer 109 is for aligning the magnetization direction of the free magnetic layer 105, but increases the bias magnetic field generated from the hard bias layer (hard magnetic layer) 109 in the vicinity of the free magnetic layer 105. is required.
[0009]
However, in such a spin-valve type thin film element, that is, the antiferromagnetic layer 102 is left in both side regions as well as the central portion, and the bias underlayer 108 and the hard bias layer are formed on the antiferromagnetic layers 102 on both sides. 109 has a structure in which the crystal orientation of the hard bias layer 109 on the antiferromagnetic layer 102 becomes an undesired direction, causing a problem that the magnetic characteristics of the hard bias layer 109 deteriorate. ing. As a result, the linearity and stability of the reproduced waveform are deteriorated.
[0010]
In other words, the bias characteristics of the hard bias layer 109 are very strongly dependent on the orientation structure of the bias underlayer 108 at the time of forming the hard bias layer 109. From this, it is considered that the layer structure with the antiferromagnetic layer 102 directly below it may be constrained by the crystal orientation of the antiferromagnetic layer 102 and change. For this reason, the coercive force of the hard bias layer 109 laminated on the bias underlayer 108 is reduced.
[0011]
Therefore, for example, as shown in FIG. 15, after forming the multilayer film 107 on the lower shield layer 112 and the lower gap layer 113, pre-processing milling is performed excessively when the electrode layer 111 and the hard bias layer 109 are formed. Then, in the antiferromagnetic layer 102 formed in the multilayer film 107, a portion extending on both sides and a part of the lower gap layer 113 directly below the antiferromagnetic layer 102 were removed by overetching, and then a bias underlayer 108 was laminated. A spin valve thin film element (second conventional example) is also known.
[0012]
In the spin valve thin film element having such a configuration, good hard bias characteristics can be obtained, but the bias layer 109 is tapered on the side surface of the multilayer film 107 (the thickness of the hard bias layer 109 in the vicinity of the free layer 105 is small). Decrease). Therefore, the hard bias layer 109 cannot form a desired film thickness in the vicinity of the side surface of the free magnetic layer 105. Therefore, it is difficult to more effectively apply the bias magnetic field generated from the hard bias layer (hard magnetic layer) 109 in the vicinity of the free magnetic layer 105.
[0013]
Therefore, in order to exhibit the required coercive force, at least the entire multilayer film 107 is removed or ion milling deeper than that is performed (overetch) with respect to the amount of pre-processing milling in both regions of the multilayer film 107. Is preferred. However, if all of the multilayer film is removed or ion milling is performed deeper in this way, the hard bias layer 109 becomes tapered, making it difficult to apply an effective bias magnetic field to the free magnetic layer 105, and the reproduced waveform is It lacks linearity and stability.
[0014]
OBJECT OF THE INVENTION
In view of the above circumstances, an object of the present invention is to obtain a magnetic detecting element excellent in linearity and stability of a reproduced waveform and a method for manufacturing the same.
[0015]
SUMMARY OF THE INVENTION
A magnetic sensing element according to the present invention includes a gap layer formed on a substrate, A multilayer resistive film formed by sequentially laminating at least an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer on the gap layer, a free magnetic layer of the multilayer resistive film, a nonmagnetic conductive layer, and A magnetic sensing element including a bias underlayer and a bias layer formed on both sides of a fixed magnetic layer, wherein the antiferromagnetic layer includes at least a free magnetic layer, a nonmagnetic conductive layer, and a fixed magnetic layer of a multilayer resistive film. Both sides of the antiferromagnetic layer are formed on both sides of the antiferromagnetic layer, and a bias underlayer and a bias layer are sequentially formed on the amorphous conductive layer. Stacked, the bias layer is raised by both side regions of the antiferromagnetic layer, the amorphous conductive layer, and the bias underlayer, and faces the both end surfaces of the free magnetic layer. Features.
[0016]
Preferably, the bias underlayer is formed of a bcc crystal structure, and at least the [211] plane or the [200] plane is oriented in the direction perpendicular to the film plane. The bias layer is preferably formed of a magnetic material having at least a [100] plane oriented in a direction perpendicular to the film surface. The bias underlayer may be interposed between the bias layer and the free magnetic layer.
[0017]
The amorphous conductive layer is preferably a nonmagnetic material. The amorphous conductive layer is formed of a Co-TZ alloy, T is an element including at least one of Zr and Hf, and Z is an element including at least one of Ta and Nb. Alternatively, it may be made of a Ni-X alloy, and X may be made of an element containing at least P.
[0018]
The film thickness of the antiferromagnetic layer is smaller than the thickness of the region in contact with the pinned magnetic layer between the both side regions, It is desirable that the amorphous conductive layer is formed with a desired film thickness on both side regions of the antiferromagnetic layer. The amorphous conductive layer preferably has a thickness of 60 to 300 mm.
[0019]
The pinned magnetic layer is The structure may include a pair of ferromagnetic layers formed with a nonmagnetic intermediate layer interposed therebetween, and the magnetization directions of the pair of ferromagnetic layers may be antiparallel to each other. Moreover, it is desirable that a seed layer layer be formed between the gap layer and the antiferromagnetic layer.
[0020]
The free magnetic layer The structure may include a pair of ferromagnetic layers formed with a nonmagnetic intermediate layer interposed therebetween, and the magnetization directions of the pair of ferromagnetic layers may be antiparallel to each other.
[0021]
In addition, the method of manufacturing the magnetic detection element of the present invention includes: Forming a multilayer resistive film on the gap layer of the substrate by laminating at least an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer in order; Patterning the multilayer resistive film by etching and overetching both sides of the antiferromagnetic layer; forming an amorphous conductive layer on the overetched regions on both sides of the antiferromagnetic layer; The method includes a step of forming a bias underlayer on the amorphous conductive layer and a step of forming a bias layer on the bias underlayer.
[0022]
Further, in the bias underlayer forming step, the film forming angle of the bias underlayer made of a bcc structure crystal structure is controlled so that at least the [211] plane or the [200] plane is oriented in the direction perpendicular to the film plane. Thus, it is desirable to form the bias underlayer.
[0023]
In the step of forming the bias layer, it is desirable to form the bias layer by controlling the film forming angle of the bias layer so that at least the [100] plane is oriented in the direction perpendicular to the film surface. .
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0025]
FIG. 1 is a cross-sectional view of the magnetic detection element according to the first embodiment of the present invention as viewed from the surface facing the recording medium (ABS surface), and FIG. 2 is an enlarged cross-sectional view of the right side shape of FIG. is there.
[0026]
The magnetic detection element according to the first embodiment is a giant magnetoresistive element for reproducing data recorded on a recording medium. This magnetic detection element is used in a magnetic head for reproduction, and from the recording medium. The electrical resistance changes due to the signal magnetic field, and the recorded data on the recording medium is reproduced using the change in resistance.
[0027]
FIG. 1 discloses only a magnetic detection element used for a magnetic head for reproduction, but a recording inductive head is laminated on the multilayer resistance film 20 (Z direction) of this magnetic detection element. It may be of a structure. This inductive head has a core layer formed of a magnetic material and a coil layer wound around the core layer, and has a structure in which a recording current is supplied to the coil layer and data is written to the recording medium by a magnetic field generated in the core layer. It is configured.
[0028]
The magnetic detecting element of FIG. 1 used for the reproducing magnetic head is, for example, alumina-titanium carbide (Al ₂ O _Three -TiC) provided on the trailing end face of the slider. This slider is bonded to an elastically deformable suspension made of stainless steel or the like on the side opposite to the surface facing the recording medium to constitute a magnetic head device.
[0029]
In this magnetic detection element, a lower shield layer 21 made of a magnetic material such as NiFe alloy or Sendust is formed on a substrate B, and Al is formed on the lower shield layer 21. ₂ O _Three And SiO ₂ The lower gap layer 22 is formed using an insulating material such as, and the multilayer resistive film 20 is formed on the formation surface α of the lower gap layer 22.
[0030]
The multilayer resistance film 20 is a so-called spin valve type multilayer resistance film. Hereinafter, each layer constituting the multilayer resistive film 20 will be described.
[0031]
First, the antiferromagnetic layer 26 is formed on the formation surface α located on the upper surface of the lower gap layer 22. The antiferromagnetic layer 26 includes, for example, an element X (where X is one or more elements among Pt, Pd, Ir, Rh, Ru, and Os) and Mn. Material or element X and element X ′ alloy (where element X ′ is Ne, Ar, Kr, Xe, Be, B, C, N, Mg, Al, Si, P, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ag, Cd, Sn, Hf, Ta, W, Re, Au, Pb, and one or more elements among rare earth elements And an antiferromagnetic material containing Mn. In general, the antiferromagnetic layer 26 is made of PtMn (platinum manganese). Further, the film thickness t2 of both side regions 26b of the antiferromagnetic layer 26 is formed thinner than the film thickness t1 of the track width region 26a, and the antiferromagnetic layer 26 is formed in a convex shape on the lower gap layer 22.
[0032]
These antiferromagnetic materials have excellent corrosion resistance and high blocking temperature, and can generate a large exchange coupling magnetic field at the interface with the pinned magnetic layer 27 formed on the antiferromagnetic layer 26.
[0033]
A pinned magnetic layer 27 is formed on the antiferromagnetic layer 26. This pinned magnetic layer 27 is formed of NiFe alloy, CoFe alloy, Co, CoNiFe alloy or the like. After the pinned magnetic layer 27 is formed on the antiferromagnetic layer 26, annealing is performed in a magnetic field atmosphere in the height direction (Y direction in the drawing), whereby the interface between the pinned magnetic layer 27 and the antiferromagnetic layer 26. The magnetization of the pinned magnetic layer 27 is pinned in the height direction (Y direction in the drawing) by the exchange coupling magnetic field generated in the. The pinned magnetic layer 27 is formed with a film thickness of about 20 to 60 mm, for example.
[0034]
A nonmagnetic conductive layer 28 is formed on the pinned magnetic layer 27. The nonmagnetic conductive layer 28 is formed of a conductive material having a low electrical resistance such as Cu. The nonmagnetic conductive layer 28 is formed with a film thickness of about 25 mm, for example.
[0035]
A free magnetic layer 29 is formed on the nonmagnetic conductive layer 28. The free magnetic layer 29 is formed of a NiFe alloy, a CoFe alloy, Co, a CoNiFe alloy, or the like. The free magnetic layer 29 has a width in the X direction set to a dimension of a track width Tw corresponding to magnetic reproduction. The free magnetic layer 29 is formed with a film thickness of about 20 to 40 mm. The free magnetic layer 29 may be formed with a Cr or CoFe film or the like on the side facing the nonmagnetic conductive layer 28. Thereby, the diffusion of a metal element or the like at the interface with the nonmagnetic conductive layer 28 can be prevented, and the resistance change rate (ΔGMR) can be increased.
[0036]
A protective layer 30 is formed on the free magnetic layer 29. This protective layer 30 is made of Ta or the like. This protective layer 30 is formed with a film thickness of about 30 mm.
[0037]
A region composed of the antiferromagnetic layer 26 to the protective layer 30, that is, a region having a substantially trapezoidal cross-sectional shape when viewed from the ABS surface direction, specifically, X1 (bottom side) in FIG. The multilayer resistive film 20 in each layer region (hereinafter referred to as a track region) having a width between X2 (upper side) has anti-strength on both side end surfaces 20a and 20a in the track width direction (X direction in the drawing). The magnetic layer 26 is formed into a continuous inclined surface from the upper surface side to the upper surface of the protective layer 30. Note that the size of the track width region varies depending on the amount of overetching of the antiferromagnetic layer 26. For example, when the amount of overetching of the antiferromagnetic layer 26 is maximum, the film thickness of an amorphous conductive layer 32 to be described later is maximum (large t), and the dimension of the track width region is maximum X1. When the amount of overetching of the antiferromagnetic layer 26 is minimum, the film thickness of an amorphous conductive layer 32 described later is minimum (small t), and the dimension of the track width region is minimum X1 ′. Thereby, the antiferromagnetic layer 26 is formed to extend from the track width Tw dimension of the free magnetic layer 29 to both sides in the track width direction. In this case, it has been technically confirmed that increasing the amount of overetching of the antiferromagnetic layer 26 as much as possible tends to increase the rate of change in electrical resistance of the multilayer resistive film 20.
[0038]
The multilayer resistance film 20 is formed by first forming each layer on the formation surface α of the lower gap layer 22, and then forming a lift-off resist (see FIG. 6) only on the central portion of the multilayer resistance film 20. The regions on both sides of the multilayer resistive film 20 not covered by the etching are removed by etching by ion milling or the like. At this time, both side surfaces of the multilayer resistive film 20 are formed into an inclined surface by etching.
[0039]
In this embodiment, the multilayer resistive film 20 is located outside the both end faces 20a, 20a, that is, is located so as to face the track region from the outside in the track width direction relative to the track region, and is a region satisfying X0 and Z0 simultaneously ( For each layer (hereinafter referred to as both side regions), only a part of the antiferromagnetic layer 26 is left and all the layers above it are removed to form, for example, a substantially trapezoidal shape as shown in FIG. The track region of the antiferromagnetic layer 26 is overetched to form a convex shape, and the amorphous conductive layer 32 is formed in the overetched portion of the convex antiferromagnetic layer 26 on both sides in the track width direction. Is done.
[0040]
As shown in FIG. 1, an amorphous conductive layer 32, a bias underlayer 33, a hard bias layer 34, an electrode layer 36, and a protective layer 37 are formed on both sides of the substantially trapezoidal multilayer resistive film 20 from the bottom. . Each layer will be described mainly with reference to FIG.
[0041]
FIG. 2 is an enlarged cross-sectional view of only the right side portion of the magnetic detection element shown in FIG. As shown in FIG. 2, the amorphous conductive layer 32 is formed on both sides of the convex antiferromagnetic layer 26 of the multilayer resistive film 20, particularly on the over-etched region, and the amorphous conductive layer 32 is on the multilayer resistive film 20 side. These end faces 32 a are formed in contact with both end faces 20 a of the multilayer resistive film 20. The amorphous conductive layer 32 is formed on both side regions 26b having a thickness t2 smaller than the thickness t1 of the track region 26a of the antiferromagnetic layer 26, and a desired thickness is secured. The film thickness of the amorphous conductive layer 32 is desirably 60 to 300 mm.
[0042]
In the amorphous conductive layer 32, the crystal orientation characteristics from the antiferromagnetic layer 26 located immediately below the amorphous conductive layer 32 adversely affect the crystal orientation of the bias underlayer 33 and the hard bias layer 34 formed thereon. By interposing an amorphous conductive layer 32 of an amorphous non-magnetic material whose crystal structure is not ordered, the antiferromagnetic layer 26 has a crystal orientation of the bias underlayer 33. It functions so as not to adversely affect the crystal orientation.
[0043]
In addition, the amorphous conductive layer 32 also functions as a base material for raising the bias base layer 33 and the hard bias layer 34, and the hard bias layer 34 formed therebetween is used as a region on both sides of the multilayer resistive film 20. The hard bias layer 34 is opposed to the free magnetic layer 29 with a sufficient volume on both sides. Further, the film thickness of the amorphous conductive layer 32 is set in a range of 60 to 300 mm so as not to adversely affect the crystal orientation of the bias underlayer 33.
[0044]
As will be described later in the manufacturing method, the amorphous conductive layer 32 is formed by ion irradiation from a substantially vertical direction with respect to the antiferromagnetic layer 26 on the formation surface α at the time of sputtering film formation. In particular, the amorphous conductive layer 32 is formed using an ion beam sputtering method, a long throw sputtering method, a collimation sputtering method, or the like. Since part of the amorphous conductive layer 32 adheres to the inclined surface 20a of the multilayer resistive layer 20 by sputtering film formation, the excess amorphous conductive layer 32 attached to the inclined surface 20a of the multilayer resistive film 20 is removed by etching. .
[0045]
Further, the upper surface 32b of the amorphous conductive layer 32 is preferably located above (the Z direction in the drawing) the lower surface 26a of the antiferromagnetic layer 26. As a result, the hard bias layer 34 can be formed at a high position in the both side regions of the multilayer resistive film 20, and the hard bias layer 34 can be made to have a sufficient volume on both sides of the free magnetic layer 29. .
[0046]
A bias underlayer 33 is formed on the amorphous conductive layer 32. In this case, the bias base layer 33 is formed with a flat portion 33 a on the amorphous conductive layer 32 and extended portions 33 b on both side end surfaces 20 a of the multilayer resistive film 20. Further, the bias underlayer 32 is formed of a bcc crystal structure, and at least the [211] plane or the [200] plane is oriented in the direction perpendicular to the film plane.
[0047]
As described in the manufacturing method described later, the incident angle of the sputtered particles with respect to the direction perpendicular to the formation surface α when forming the bias underlayer 33 is larger than the incident angle of the sputtered particles when forming the amorphous conductive layer 32. As a result, the bias underlayer 33 is formed not only on the amorphous conductive layer 32 but also on both end surfaces 20a of the multilayer resistive film 20, but the bias underlayer 33 has at least the [211] plane or the [200] plane as a film. Since the orientation is perpendicular to the plane, the magnetic characteristics of the hard bias layer 34 facing the free magnetic layer 29 are improved by the bias underlayer 33. This is demonstrated by the examples described below.
[0048]
Note that an amorphous conductive layer 32 is formed below the bias base layer 33 formed on both sides of the multilayer resistive film 20, and the antiferromagnetic layer 26 is not directly formed. For this reason, the bias underlayer 33 is not strongly influenced by the crystal orientation of the antiferromagnetic layer 26. Therefore, the coercive force of the hard bias layer 34 formed on the bias underlayer 33 can be increased.
[0049]
As described above, the amorphous conductive layer 32 on the antiferromagnetic layer 26 on the formation surface α also has a function of raising the bias underlayer 33 on the formation surface α. Thus, the hard bias layer 34 formed on the bias underlayer 33 can be formed at a high position corresponding to the height position of the free magnetic layer 29 of the multilayer resistive film 20, and one layer is formed on both sides of the free magnetic layer 29. The hard bias layer 34 can be opposed to have a sufficient volume.
[0050]
A hard bias layer 34 is formed on the bias base layer 33. In this embodiment, the lower surface 34 a of the hard bias layer 34 is located at a position via the amorphous conductive layer 32 and the bias underlayer 33, that is, on the flat portion 33 a of the bias underlayer 33, in the overetched portion of the antiferromagnetic layer 26. The upper surface 34b of the hard bias layer 34 is located lower than the lower surface 29a of the free magnetic layer 29 in the drawing (in the opposite direction to the Z direction in the drawing) and the flat portion 33a is lower than the lower surface 29a of the free magnetic layer 29. It is preferable to be located on the upper side in the figure (Z direction in the figure). As a result, the hard bias layer 34 can be opposed to the both sides of the free magnetic layer 29 with a sufficiently large volume. The hard bias layer 34 is formed of a magnetic material in which at least the [100] plane is preferentially oriented in the direction perpendicular to the film plane. The hard bias layer 34 has at least the [100] plane oriented in the direction perpendicular to the film plane, the bias underlayer 33 has at least the [211] or [200] plane oriented in the film plane perpendicular direction, and Since the amorphous conductive layer 32 is not affected by the antiferromagnetic layer 26, the magnetic characteristics of the hard bias layer 34 are improved, and the coercive force Hc of the hard bias layer 34 becomes a value of 160 KA / m or more that is practically used. In this case, the squareness ratio S of the hard bias layer 34 is 0.8 or more. This is demonstrated by the examples.
[0051]
Further, the upper surface 34b of the hard bias layer 34 on the flat portion 33a of the bias underlayer 33 is positioned substantially on the same plane as the upper surface 29b of the free magnetic layer 29, or on the upper side of the upper surface 29b of the free magnetic layer 29 in the drawing ( More preferably, it is located in the Z direction in the figure. Thus, when the imaginary lines D and E are drawn from the lower surface 29a and the upper surface 29b of the free magnetic layer 29 in the direction parallel to the formation surface α, the inside of the two imaginary lines D and E in the both side regions of the multilayer resistive film 20 Since only the extending portion 33 b of the bias underlayer 33 and the hard bias layer 34 exist, a sufficient bias magnetic field can be supplied from the hard bias layer 34 to the free magnetic layer 29.
[0052]
In addition, if only the extending portion 33b of the thin bias underlayer 33 having a tapered thickness is interposed between the hard bias layer 34 and the free magnetic layer 29, the bias magnetic field from the hard bias layer 34 becomes extremely small. Therefore, a sufficiently large bias magnetic field can be supplied to the free magnetic layer 29.
[0053]
With the above-described configuration, a bias magnetic field having an appropriate magnitude can be supplied from the hard bias layer 34 to the free magnetic layer 29, whereby the magnetization of the free magnetic layer 29 can be appropriately single-domained in the X direction shown in the figure. It is.
[0054]
An electrode layer 36 is formed on the hard bias layer 34, and a protective layer 37 made of Ta or the like is formed on the electrode layer 36.
[0055]
Next, materials for the amorphous conductive layer 32 and the bias underlayer 33 will be described below.
[0056]
As described above, the amorphous conductive layer 32 has an effect of cutting off the influence of this orientation characteristic even if the antiferromagnetic layer 26 exists immediately below due to its amorphous property. Is made of a non-magnetic material.
[0057]
When the amorphous conductive layer 32 is formed of a Co—TZ alloy, T is an element including at least one of Zr and Hf, and Z is an element including at least one of Ta and Nb. is there. Further, when the amorphous conductive layer 32 is formed of a Ni—X alloy, X is composed of an element containing at least P. The film thickness of the amorphous conductive layer 32 is set in the range of 60 to 300 mm.
[0058]
On the other hand, the bias underlayer 33 is preferably formed of a metal film having a bcc structure (body-centered cubic structure). When the bias underlayer 33 is formed, at least the [211] plane or the [200] plane is oriented in the direction perpendicular to the film plane by controlling the film forming direction.
[0059]
As described above, since the amorphous conductive layer 32 is formed under the bias underlayer 33 and the antiferromagnetic layer 26 is not directly formed, the crystal structure of the bias underlayer is appropriate for the body-centered cubic structure (bcc structure). Can be adjusted. The reason why the bias underlayer 33 is formed of the metal film having such a crystal structure and crystal orientation is that the coercive force (Hc) and the squareness ratio (S) of the hard bias layer 34 formed on the bias underlayer 33 are as follows. ).
[0060]
The hard bias layer 34 is formed of a CoPt alloy, a CoPtCr alloy, or the like. The crystal structure of these alloys is a dense hexagonal structure (hcp). The hard bias layer 34 is formed so that the direction perpendicular to the film surface has a [100] plane orientation.
[0061]
Here, the hcp structure of the CoPt alloy constituting the bias underlayer 33 of the bcc structure and the hard bias layer 34 formed of a metal film has a lattice matching relationship, for example, the c-axis of the hcp structure of the hard bias layer 34. Are oriented in the film plane. This is a very advantageous structure as the hard bias layer 34 magnetized in the film plane. For this reason, it can have a larger coercive force and a favorable squareness ratio.
[0062]
Since the bias underlayer 33 has a body-centered cubic structure (bcc structure), the metal film is made of one or more elements of Cr, W, Mo, V, Mn, Nb, and Ta. It is preferably formed, but it is particularly preferable that it is formed of a Cr film. This is because this Cr film is excellent in the function of adjusting the crystal orientation of the hard bias layer 34, and the coercive force of the hard bias layer 34 can be appropriately increased.
[0063]
As shown in FIG. 1, an upper gap layer 38 is formed on the multilayer resistive film 20 formed on the formation surface α using an insulating material, and a magnetic material is used on the upper gap layer 38. An upper shield layer 39 is formed.
[0064]
Next, a second embodiment of the present invention will be described with reference to FIG. This magnetic detection element is also used in a magnetic head for reproducing data recorded on a recording medium. FIG. 3 shows only this magnetic detection element, but an inductive head for recording may be formed on the magnetic head of this magnetic detection element as in the first embodiment.
[0065]
The difference of this embodiment from the first embodiment is that a seed layer layer 25 is provided between the antiferromagnetic layer 26 and the gap layer 22 of the multilayer resistive film 20. That is, in this embodiment, the seed layer layer 25 is formed on the lower gap layer 22 formed on the lower shield layer 21.
[0066]
The seed layer 25 is a non-magnetic material in which the [111] plane of the face-centered cubic crystal or the [110] plane of the body-centered cubic crystal is preferentially oriented in the direction parallel to the interface between the underlayer 23 and the antiferromagnetic layer 26. The alignment film 24 is made of a material or a magnetic material.
[0067]
The seed layer 25 may be composed of only a single nonmagnetic material or an alignment layer 24 formed of a magnetic material, but in order to adjust the crystal orientation of the alignment layer 24, a base layer 23 is formed. Is preferred.
[0068]
The underlayer 23 is formed of at least one of Ta (tantalum), Hf (hafnium), Nb (niobium), Zr (zirconium), Ti (titanium), Mo (molybdenum), and W (tungsten). Is preferred. In addition, the alignment layer 24 is formed of a magnetic material or a nonmagnetic material as described above, but is preferably formed of a high resistance material. The alignment layer 24 is preferably formed of, for example, a NiFeY alloy (where Y is at least one selected from Cr, Rh, Ta, Hf, Nb, Zr, and Ti). Of these, the alignment layer 24 is more preferably formed of a NiFeCr alloy. This is because the [111] plane of the orientation layer 24 can be more preferentially oriented in a direction parallel to the interface with the antiferromagnetic layer 26, and can have a higher specific resistance.
[0069]
If the alignment layer 24 has a high specific resistance, it is possible to suppress a shunting of a sense current flowing from an electrode layer 36 described later to the seed layer 25. As a result, the resistance change rate (ΔMR) can be improved and Barkhausen noise can be reduced. The seed layer 25 may be formed of a single Cr layer. When the Cr single layer is formed, each crystal grain grows to a uniform height due to its high wettability, so that the undulation of the film surface is eliminated and the symmetry of the output signal is improved.
[0070]
In the seed layer 25, the underlayer 23 is formed with a thickness of about 0 to 50 mm, and the alignment layer 24 is formed with a thickness of about 10 to 100 mm.
[0071]
An antiferromagnetic layer 26 is formed on the seed layer 25, which has the same configuration as that of the first embodiment. That is, the antiferromagnetic layer 26 has excellent corrosion resistance and a high blocking temperature, and can generate a large exchange coupling magnetic field at the interface with the pinned magnetic layer 27 formed on the antiferromagnetic layer 26. The antiferromagnetic layer 26 is preferably formed with a thickness of 50 to 250 mm.
[0072]
As described above, in the seed layer 25, the face-centered cubic [111] plane or the body-centered cubic [110] plane is preferentially oriented in the direction parallel to the interface with the antiferromagnetic layer 26. Thus, the [111] plane of the antiferromagnetic layer 26 formed on the seed layer 25, the [111] plane of each layer formed on the antiferromagnetic layer 26, and the antiferromagnetic layer 26 It is possible to preferentially orient in the direction parallel to the [111] plane of each layer to be formed, which increases the crystal grain size and improves the low resistivity (ΔGMR).
[0073]
The pinned magnetic layer 27 is preferably formed with a thickness of about 20 to 60 mm. On the other hand, the nonmagnetic conductive layer 28 is formed with a film thickness of about 25 mm, for example. The free magnetic layer 29 is preferably formed with a thickness of about 20 to 40 mm. The free magnetic layer 29 is preferably formed in a two-layer structure, and a Co film is formed on the side facing the nonmagnetic conductive layer 28. Thereby, the diffusion of a metal element or the like at the interface with the nonmagnetic conductive layer 28 can be prevented, and the resistance change rate (ΔGMR) can be increased. The protective layer 30 on the free magnetic layer 29 is made of Ta or the like and has a thickness of about 30 mm.
[0074]
Also in the second embodiment, both end surfaces 20 a and 20 a in the track width direction (X direction in the drawing) of the multilayer resistive film 20 including the seed layer 25 to the protective layer 30 are formed from the lower surface of the seed layer 25. The inclined surface is continuous to the upper surface of the protective layer 30.
[0075]
As in the first embodiment, the multilayer resistance film 20 is formed by first forming each layer on the formation surface α, and then forming a lift-off resist layer only on the central portion of the multilayer resistance film 20. The regions on both sides of the multilayer resistive film 20 that are not covered with layers are removed by etching.
[0076]
The both side regions of the multilayer resistive film 20 are configured not to be etched deeply until the formation surface α is exposed, and to leave a part of the seed layer 25 or a part of the antiferromagnetic layer 26.
[0077]
In the both side regions of the multilayer resistive film 20, similarly to the first embodiment, an amorphous conductive layer 32, a bias underlayer 33, a hard bias layer 34, an electrode layer 36, and a protective layer 37 are sequentially arranged from the bottom. Each is formed.
[0078]
The amorphous conductive layer 32 is formed on the formation surface α in both side regions of the multilayer resistive film 20, but the end surface 32 a on the multilayer resistive film 20 side of the amorphous conductive layer 32 is in contact with the both side end surfaces 20 a of the multilayer resistive film 20. It is formed. The hard bias layer 34 formed on the amorphous conductive layer 32 via the bias base layer 33 is formed at a high position in both side regions of the multilayer resistance film 20 and has a sufficient volume on both sides of the free magnetic layer 29. Facing each other.
[0079]
The film thickness of the amorphous conductive layer 32 on the formation surface α is preferably 60 mm or more and 300 mm or less. The thickness of the bias underlayer 33 is preferably 35 mm or more and 75 mm or less.
[0080]
Also in this embodiment, the amorphous conductive layer 32 is formed by ion irradiation from a direction substantially perpendicular to the formation surface α during sputtering. A part of the amorphous conductive layer 32 for raising the bulk is formed on both end faces 20a of the multilayer resistive film 20, and this part is removed by etching.
[0081]
Note that the upper surface 32 b of the amorphous conductive layer 32 is preferably positioned above (in the Z direction in the drawing) the lower surface 26 a of the antiferromagnetic layer 26. As a result, the hard bias layer 34 can be formed at a high position in both side regions of the multilayer resistive film 20, and can be opposed to both sides of the free magnetic layer 29 with a sufficient volume.
[0082]
In this embodiment, the amorphous conductive layer 32 exists under the bias base layer 33 formed in both side regions of the multilayer resistive film 20, and the seed layer layer 25 and the antiferromagnetic layer 26 exist below the amorphous conductive layer 32. For this reason, the bias underlayer 33 is not affected by the crystal orientation of the seed layer 25 and the antiferromagnetic layer 26. Therefore, the coercive force of the hard bias layer 34 formed on the bias underlayer 33 can be increased. Moreover, since both sides of the amorphous conductive layer 32 and the antiferromagnetic layer 26 are interposed under the bias underlayer 33 to increase the bias underlayer 33 and the hard bias layer 34, the bias underlayer 33 is tapered. It is possible to eliminate the inconvenience that the volume is reduced due to the state.
[0083]
The lower surface 34a of the hard bias layer 34 on the flat portion 33a of the bias underlayer 33 is located below the lower surface 29a of the free magnetic layer 29 (reverse to the Z direction in the drawing) and on the flat portion 33a. The upper surface 34b of the hard bias layer 34 is preferably located above the lower surface 29a of the free magnetic layer 29 in the drawing (Z direction in the drawing).
[0084]
Further, in this embodiment, in addition to the above configuration, the upper surface 34b of the hard bias layer 34 on the flat portion 33a of the bias underlayer 33 is located on the same plane as the upper surface 29b of the free magnetic layer 29, or More preferably, the free magnetic layer 29 is positioned on the upper side (Z direction in the drawing) of the upper surface 29b. Thus, when imaginary lines (not shown) are drawn from the lower surface 29 a and the upper surface 29 b of the free magnetic layer 29 in the direction parallel to the formation surface α, they are within the two imaginary lines in both side regions of the multilayer resistive film 31. Since only the extending portion 33 b of the bias underlayer 33 and the hard bias layer 34 exist, a sufficient bias magnetic field can be supplied from the hard bias layer 34 to the free magnetic layer 29.
[0085]
Further, in this embodiment, the extended portion 33b of the taper-shaped thin bias underlayer 33 is interposed between the hard bias layer 34 and the free magnetic layer 29 as in the previous embodiment. The bias magnetic field from the hard bias layer 34 is not extremely reduced, and a sufficiently large bias magnetic field can be supplied to the free magnetic layer 29.
[0086]
In this embodiment, the amorphous conductive layer 32 exists under the bias underlayer 33, and the seed layer layer 25 and the antiferromagnetic layer 26 exist below the amorphous conductive layer 32. Therefore, the crystal structure of the bias underlayer 33 can be appropriately adjusted to a body-centered cubic structure (bcc structure). Similarly to the previous embodiment, the bias underlayer 33 is preferably formed of a metal film having a body-centered cubic structure (bcc structure), and the bias underlayer 33 has a crystal orientation of [200], [211] It has a plane orientation.
[0087]
The hard bias layer 34 of this embodiment is also formed of a CoPt alloy, a CoPtCr alloy, or the like, and the crystal structure of these alloys is a dense hexagonal structure (hcp).
[0088]
Also in this embodiment, the (hcp) structure of the CoPt-based alloy constituting the bias underlayer 33 of the bcc structure and the hard bias layer 34 formed of the metal film described above has a hard ba ice layer due to the lattice matching relationship. The c-axis of the 34 hcp structure is oriented in the film plane. As a result, it is a very advantageous structure as the hard bias layer 34 used by being magnetized in the film surface. That is, it can have a larger coercive force (Hc) and a good squareness ratio.
[0089]
Also in this embodiment, as shown in FIG. 3, the upper gap layer 38 is formed on the multilayer resistance film 20 formed on the formation surface α by using an insulating material. An upper shield layer 39 is formed on the top using a magnetic material.
[0090]
Therefore, according to the second embodiment, the seed layer layer 25 is formed in the lowermost layer, and the antiferromagnetic layer 26 is formed thereon, whereby the crystal orientation of the antiferromagnetic layer 26 is adjusted, and the multilayer The resistance change rate of the resistance film 20 can be improved.
[0091]
Further, according to this embodiment, the amorphous conductive layer 32 exists below the bias base layer 33 formed on both sides of the multilayer resistive film 20, and the seed layer layer 25 exists below the amorphous conductive layer 32. The underlayer 33 can be formed with an appropriate crystal structure and crystal orientation. As a result, the coercive force of the hard bias layer 34 formed on the bias underlayer 33 can be increased.
[0092]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a partial cross-sectional view of the magnetic detection element according to the third embodiment of the present invention as viewed from the surface facing the recording medium (ABS surface).
[0093]
This magnetic detection element is also used in a magnetic head for reproducing data recorded on a recording medium. Although only the magnetic detection element is shown in FIG. 4, as in the first embodiment, a recording inductive head may be formed on the magnetic head of this magnetic detection element.
[0094]
The difference between the third embodiment of FIG. 4 and the first embodiment of FIG. 1 is the structure of the pinned magnetic layer 27 and the free magnetic layer 29. In FIG. 1, both the pinned magnetic layer 27 and the free magnetic layer 29 are formed of a single layer, but in FIG. 4, both the pinned magnetic layer 27 and the free magnetic layer 29 are formed of three layers.
[0095]
The pinned magnetic layer 27 includes a ferromagnetic layer 40, a nonmagnetic intermediate layer 41, and a ferromagnetic layer 42. The ferromagnetic layers 40 and 42 are made of, for example, Co (cobalt), and the nonmagnetic intermediate layer 41 is made of a nonmagnetic layer such as, for example, Ru (ruthenium). With this three-layer configuration, the magnetization directions of the ferromagnetic layer 40 and the ferromagnetic layer 42 are antiparallel to each other. This is a so-called ferrimagnetic state, in which the magnetization of the pinned magnetic layer 27 can be stabilized, and the exchange coupling magnetic field generated at the interface between the pinned magnetic layer 27 and the antiferromagnetic layer 26 can be increased. it can.
[0096]
Similarly, the free magnetic layer 29 includes a ferromagnetic layer 43 and a ferromagnetic layer 45 made of Co or the like, and a nonmagnetic intermediate layer 44 such as Ru between the ferromagnetic layers 43 and 45. As a result, the magnetizations of the ferromagnetic layers 43 and 45 are antiparallel to each other, the magnetization of the free magnetic layer 29 can be maintained in a stable state, and the magnetic thickness of each of the ferromagnetic layers 43 and 45 can be reduced. As a result, the magnetization of the free magnetic layer 29 is easily reversed while the ferromagnetic layers 43 and 45 are antiparallel to the external magnetic field, and the reproduction characteristics can be improved. This ferri structure may be formed in either the pinned magnetic layer 27 or the free magnetic layer 29.
[0097]
The thicknesses of the ferromagnetic layers 40 and 42 and the ferromagnetic layers 43 and 45 are each about 10 to 70 mm. The film thickness of the nonmagnetic intermediate layers 41 and 44 is about 3 to 10 mm.
[0098]
Also in the third embodiment, the lowermost layer of the multilayer resistive film 46 is the seed layer layer 25, and both end faces 46 a and 46 a in the track width direction (X direction in the drawing) of the multilayer resistive film 46 are formed on the seed layer layer 25. The inclined surface is continuous from the lower surface to the upper surface of the protective layer 30. In addition, since the amorphous conductive layer 32 exists below the bias base layer 33 and the seed layer 25 and the antiferromagnetic layer 26 exist below the bias conductive layer 33, the bias base layer 33 is maintained in a predetermined crystal orientation. Can do.
[0099]
In addition, the amorphous conductive layer 32 is formed on both sides of the convex antiferromagnetic layer 26 of the multilayer resistance film 46 (particularly, the portions where overetching has been performed), so that the hard bias layer 34 having a large coercive force can be replaced with the free magnetic layer 29. Can be opposed to each other with a sufficient film thickness. In addition, since the thickness of the bias underlayer 33 interposed between the free magnetic layer 29 and the hard bias layer 34 can be reduced, the bias magnetic field from the hard bias layer 34 can be sufficiently supplied to the free magnetic layer 29, and free magnetic The formation of a single domain in the layer 29 can be promoted.
[0100]
Furthermore, it is desirable to form the amorphous conductive layer 32 up to the upper surface of the intermediate layer 41 of the pinned magnetic layer 27. That is, by reducing the flow of the sense current into the intermediate layer 41, the magnetic layer 40, and the antiferromagnetic layer 26 of the pinned magnetic layer 27, the santros can be reduced and the output can be increased.
[0101]
Next, FIGS. 5 to 10 are cross-sectional views showing the method of manufacturing the magnetic sensing element shown in FIG. Each drawing is a partial cross-sectional view as viewed from the surface facing the recording medium (ABS surface).
[0102]
In the process shown in FIG. 5, a lower shield layer 21 formed of a magnetic material such as permalloy or sendust is formed on the substrate B, and a lower gap layer formed of an insulating material such as alumina is formed on the lower shield layer 21. 22 is formed.
[0103]
Next, each layer constituting the multilayer resistance film 20 of the magnetic detection element is formed on the entire surface of the lower gap layer 22. That is, first, an antiferromagnetic layer 26 made of a PtMn alloy or the like is formed on the lower gap layer 22. Further, on the antiferromagnetic layer 26, a pinned magnetic layer 27 formed of a magnetic material such as a NiFe alloy, a nonmagnetic conductive layer 28 formed of Cu, a free magnetic layer 29 formed of a NiFe alloy, and the like. A protective layer 30 is formed.
[0104]
In order to form the seed layer 25 shown in FIG. 3, first, the seed layer 25 composed of the underlayer 23 such as Ta and the nonmagnetic material layer 24 such as NiFeCr alloy is formed on the lower gap layer 22. To do. Next, an antiferromagnetic layer 26 made of a PtMn alloy or the like is formed on the seed layer 25. In order to form the multilayer resistance film 46 shown in FIG. 4, the fixed magnetic layer 27 and the free magnetic layer 29 are formed in a ferrimagnetic state.
[0105]
Next, as shown in FIG. 5, a lift-off resist R is formed by patterning in the central portion on the protective layer 30 by a coating process and an exposure development process. As shown in FIG. 5, the lower surface 57b of the resist R is provided with notches 57a and 57a.
[0106]
Next, in the step shown in FIG. 6, both side regions 20b and 20b in the track width direction (X direction in the drawing) of the multilayer resistive film 20 not covered with the resist R are removed by etching.
[0107]
In this embodiment, both side regions 20b and 20b of the multilayer resistive film 20 are shallow to a depth that does not expose the upper surface of the lower gap layer 22 (the magnetoresistive effect element formation surface α). Part is over-etched and etched. As a result, the both side end surfaces 20a, 20a of the remaining multilayer resistive film 20 become inclined surfaces that continue from the upper surface of the antiferromagnetic film 26 to the upper surface of the protective layer 30, and the multilayer resistive film 31 has a substantially trapezoidal shape.
[0108]
Next, as shown in FIG. 7, an amorphous conductive layer 32 is formed by sputtering on both sides of the convex antiferromagnetic layer 26 (particularly, portions where overetching is performed). At this time, the end face 32a of the amorphous conductive layer 32 on the multilayer resistance film 20 side is in contact with both end faces 20a of the multilayer resistance film 20.
[0109]
As shown in FIG. 7, the amorphous conductive layer 32 is formed by sputtering with the first sputtered particle incident angle θ <b> 1 with respect to the direction perpendicular to the formation surface α (the Z direction in the drawing). Specifically, the first sputtered particle incident angle θ1 is preferably not less than 0 ° and not more than 10 °. At this time, a layer 32 ′ of the same material as the amorphous layer 32 is attached to the resist R.
[0110]
That is, the amorphous conductive layer 32 is formed by sputtering from a direction substantially perpendicular to the formation surface α. Specifically, it is preferably performed by a long throw sputtering method (LTS), an ion beam sputtering method (IBD), a collimation sputtering method, or the like.
[0111]
Further, the amorphous conductive layer 32 adhering to both side regions 20a of the multilayer resistive film 20 is removed by etching. In this case, it is ideal to completely remove the amorphous conductive layer 32 by etching. However, since the amorphous conductive layer 32 has conductivity, the sense current flowing through the free magnetic layer 29 is not interrupted. There is no problem even if it remains a little. Thereby, the etching process time can be shortened to protect the multilayer resistance layer 20 from etching.
[0112]
Further, the amorphous conductive layer 32 is preferably formed by controlling the film thickness of the amorphous conductive layer 32 so that the upper surface 32 b of the amorphous conductive layer 32 is located above the lower surface 26 a of the antiferromagnetic layer 26. The film thickness of the amorphous conductive layer 32 is preferably in the range of 60 to 300 mm.
[0113]
In addition, the bias underlayer 33, the hard bias layer 34, the electrode layer 36, and the protective layer 37 that are formed in the following steps are also preferably formed by the sputtering method.
[0114]
In this embodiment, the bias underlayer 33 is preferably formed of a metal film having a (bcc) crystal structure. Examples of the metal film include Cr, W, Mo, V, Mn, Nb, and Ta. One or more elements or two or more elements can be selected. The bias underlayer 33 is preferably formed by sputtering with a film.
[0115]
Next, in the step shown in FIG. 8, the bias underlayer 33 is formed by sputtering from the upper surface 32 b of the amorphous conductive layer 32 to the both end surfaces 20 a of the multilayer resistance film 20. As shown in the figure, the bias underlayer 33 is formed by sputtering with a second sputtered particle incident angle θ2 with respect to the direction perpendicular to the formation surface α (the Z direction in the drawing). The sputtered particle incident angle θ2 is preferably larger than the first sputtered particle incident angle θ1. Specifically, the second sputtered particle incident angle θ2 is preferably 15 ° or more and 60 ° or less. More preferably, it is 30 ° or more and 60 ° or less. At this time, a layer 33 ′ made of the same material as the bias underlayer 33 is also formed on the resist R.
[0116]
That is, the bias underlayer 33 is formed by sputtering from a direction more inclined with respect to the direction perpendicular to the formation surface α than when the amorphous conductive layer 32 is formed. For this reason, as shown in the figure, the bias underlayer 33 is easily formed not only on the amorphous conductive layer 32 but also on both end faces 20a of the multilayer resistance film 20. As described above, when the bias underlayer 33 is formed to extend on the both end surfaces 20 a of the multilayer resistive film 20, the bias underlayer 33 may be formed to extend to both end surfaces of the free magnetic layer 29. Although it is preferable, the bias underlayer 33 may extend only to the lower side of both end faces of the free magnetic layer 29. Further, the bias underlayer 33 may be formed only on the amorphous conductive layer 32 without extending on both end faces of the multilayer resistive film 20.
[0117]
Further, the amorphous conductive layer 32 in the process of FIG. 8 and the process in FIG. 9 are performed so that the upper surface 33 c of the bias underlayer 33 on the formation surface α is positioned below the lower surface 29 a of the free magnetic layer 29. It is preferable to perform sputter deposition while appropriately adjusting the thickness of the bias underlayer 33 at that time. Thus, the hard bias layer 34 can be opposed to the free magnetic layer 29 with a sufficient volume on both sides.
[0118]
In this embodiment, as described above, the bias underlayer 33 is preferably formed of a metal film having a crystal structure of (bcc). Examples of such a metal film include Cr, W, Mo, V, One or more of Mn, Nb, and Ta can be selected. Of these, the bias underlayer 33 is preferably formed of a Cr film. This is because this Cr film can easily change the crystal structure of the hard bias layer 34 formed in the next step to an (hcp) structure, and can increase the coercive force of the hard bias layer 34.
[0119]
Next, in the step shown in FIG. 9, a hard bias layer 34 of CoPtCr alloy or the like is formed on the bias underlayer 33 by sputtering. At this time, a layer 34 ′ made of the same material as the hard bias layer 34 is also formed on the resist R. In this embodiment, as described above, the amorphous conductive layer 32 is formed on both sides of the convex antiferromagnetic layer 26, and thereby formed on the amorphous conductive layer 32 via the bias underlayer 33. The hard bias layer 34 can be opposed to the both sides of the free magnetic layer 29 with a sufficient volume.
[0120]
Therefore, according to the magnetic detection element formed by the manufacturing method of this embodiment, the bias magnetic field from the hard bias layer 34 can be appropriately supplied to the free magnetic layer 29, and the magnetization of the free magnetic layer 29 can be appropriately made into a single magnetic domain. It is possible to do.
[0121]
In this embodiment, since the amorphous conductive layer 32 is formed under the bias underlayer 33, the antiferromagnetic layer 26 is not directly formed, and the crystal orientation of the bias underlayer 33 is appropriately adjusted. Therefore, the coercive force of the hard bias layer 34 formed on the bias underlayer 33 can be increased.
[0122]
In this embodiment, the hard bias layer 34 is formed so that the upper surface 34b of the hard bias layer 34 is located above the upper surface 29b of the free magnetic layer 29 in the step shown in FIG. preferable.
[0123]
Furthermore, if the lower surface 34 a of the hard bias layer 34 is located below the lower surface 29 a of the free magnetic layer 29, the free magnetic layer 29 in a direction parallel to the formation surface α is formed on both sides of the free magnetic layer 29. Since only the hard bias layer 34 is opposed to the free magnetic layer 29 through the bias underlayer 33 within the film thickness range, a sufficient bias magnetic field can be supplied from the hard bias layer 34 to the free magnetic layer 29, and the free magnetic layer 29 can be more appropriately applied. It is possible to promote the formation of a single magnetic domain.
[0124]
Next, in the process shown in FIG. 10, an electrode layer 36 such as Cr or Au is formed on the hard bias layer 34 by sputtering, and then a protective layer 37 such as Ta is formed on the electrode layer 36 by sputtering. At this time, a layer 36 ′ made of the same material as the electrode layer 36 and a layer 37 ′ made of the same material as the protective layer 37 are formed on the resist R so as to overlap each other.
[0125]
Then, the lift-off resist R shown in FIG. 10 is removed, and then the upper gap layer 38 and the upper shield layer 39 (not shown) are formed on the multilayer resistance film 20, thereby completing the magnetic sensing element shown in FIG.
[0126]
As described above, in this embodiment, by using one lift-off resist R on the multilayer resistive film 20, the etching process of the both side regions of the multilayer resistive film 20, the amorphous conductive layer 32, the bias underlayer 33, the hard Sputter deposition of the bias layer 34, the electrode layer 36, and the protective layer 37 can be performed continuously. For this reason, if said manufacturing method is used, the magnetic detection element concerning this embodiment can be manufactured easily.
[0127]
In this embodiment, the first sputtered particle incident angle θ1 when the amorphous conductive layer 32 is formed is smaller than the second sputtered particle incident angle θ2 when the bias underlayer 33 is formed. 32 and the bias underlayer 33 can be easily formed in a predetermined shape. Further, according to this manufacturing method, the hard bias layer 34 can be easily opposed to the both sides of the free magnetic layer 29 with a sufficient volume.
[0128]
(Example)
Next, an amorphous metal layer 32 is formed below the bias underlayer 33, a bias underlayer 33 and a hard bias layer 34 are formed in this order on the amorphous metal layer 32, and Cr is used as the bias underlayer 33. When CoPt was used as the bias layer 34, an experiment was conducted on the dependence of the X-ray diffraction (XRD) peak ratio of the hard bias layer 34 on the deposition angle of the bias underlayer 33.
[0129]
FIG. 11A shows the film formation angle of Cr used as the bias underlayer 33 and the X-ray diffraction (XRD) peak ratio between the [200] plane and the [100] plane of CoPt used as the hard bias layer 34. 11B is a graph showing the numerical values shown in FIG. 11A, and FIG. 11C is a graph showing the [200] of CoPt used as the hard bias layer. FIG. 11D is a diagram showing the relationship between the XRD peak ratio of the [100] plane and the [100] plane and the coercive force (Hc) of the bias layer 33 made of CoPt, and FIG. 11D is the diagram shown in FIG. FIG. 12 (a) shows the orientation state when the Cr film forming angle is 20 °, FIG. 12 (b) shows the orientation state when the Cr film forming angle is 50 °, and FIG. 12 (c) shows the Cr forming state. This is a multiple recording of CoPt orientation dependence and CoPt coercivity Hc dependence on film angle.
[0130]
Here, the film forming angle of the bias underlayer 33 made of Cr and the film forming angle of the hard bias layer 34 made of CoPt are angles formed by the incident direction of the sputtered particles with respect to the direction perpendicular to the substrate B (θ1, FIG. 7). (Corresponding to θ2 in FIG. 8). The deposition angle of the C0Pt film is controlled and fixed at 20 °.
[0131]
As shown in FIGS. 11 and 12, when the film forming angle of Cr is 20 °, the Cr film is only preferentially oriented with the [110] plane in the direction perpendicular to the film surface, and the CoPt film is [100]. The peak ratio (I ([100] / [200])) between the plane and the [200] plane is small (0.08), and the coercive force Hc of the CoPt film is small (136 KA / m).
[0132]
When the Cr film formation angle is 50 °, that is, when the Cr particle incidence direction is laid on the substrate B side (horizontal plane side), the [200] plane and [211] plane are preferentially oriented in addition to the [110] plane. This increases the peak ratio (I ([100] / [200])) between the [100] plane and the [200] plane in the CoPt film (0.15), and also increases the coercivity Hc of the CoPt film. (171 KA / m).
[0133]
Further, when the film formation angle of Cr as the bias underlayer 33 is set to 60 ° and the Cr particle incidence direction is laid on the substrate B side (horizontal plane side), the Cr film has a [200] plane in addition to the [110] plane. , The [211] plane is preferentially oriented, whereby the CoPt film has an increased peak ratio (I ([100] / [200])) between the [100] plane and the [200] plane (0.44), The coercivity Hc of the CoPt film also increases (191 KA / m).
[0134]
Furthermore, if the Cr deposition angle is 70 °, that is, if the Cr particle incidence direction is further laid on the substrate B side (horizontal plane side), the Cr film has priority on the [200] plane and the [211] plane in addition to the [110] plane. As a result, the CoPt film increases the peak ratio (I ([100] / [200])) between the [100] plane and the [200] plane (1.15), and the coercive force Hc of the CoPt film also increases. Increase (197 KA / m).
[0135]
If the coercive force Hc of the CoPt film as the hard bias layer 34 is 160 KA / m or more, it can be put to practical use, and control the crystal orientation of the Cr film and the orientation of the verification of the CoPt film. Thus, the coercive force of the CoPt film (hard bias layer 34) can be improved to a value that can be practically used. In the present invention, the peak ratio (I ([100] / [200])) between the [100] plane and the [200] plane of the CoPt film is preferably 0.5 or more. If it is 0.5 or more, a stable coercive force (Hc) of about 190 KA / m or more can be obtained. At this time, the film formation angle of the bias underlayer is preferably 61 ° or more. More preferably, the peak ratio (I ([100] / [200])) is 1.0 or more. When the peak ratio is 1.0 or more, the [100] plane can be preferentially oriented with respect to the [200] plane, and a large and stable coercive force of about 195 KA / m or more can be obtained. At this time, the deposition rate of the bias underlayer is preferably 67 ° or more.
[0136]
The same result is obtained when W (tungsten) is used in place of Cr as the bias underlayer 33, and the same characteristics are obtained as long as the bcc crystal structure is used as the bias underlayer 33. It has been confirmed to show. It has also been confirmed that similar characteristics are exhibited when a CoCrPt alloy is used instead of the CoPt alloy as the hard bias layer 34. In this case, it is confirmed that the film forming angle of the hard bias layer 34 is preferably around 20 °.
[0137]
In addition, although the magnetic detection element of this invention was applied to the magnetic head, it is not limited to this, You may apply similarly to a magnetic sensor.
[0138]
【The invention's effect】
As described above, according to the present invention, the bias underlayer and the bias layer are formed on the gap layer or the antiferromagnetic layer on both sides of the multilayer resistive film via the amorphous conductive layer, and the antiferromagnetic layer is formed on the antiferromagnetic layer. Since the direct bias underlayer is not formed, the amorphous conductive layer can prevent the strong orientation characteristics of the antiferromagnetic layer from directly affecting the bias underlayer, and good hard film characteristics (for example, Hc) ≧ 160 KA / m, S ≧ 0.8) can be realized with a non-tapered shape of the bias layer. Thereby, stability can be ensured and a narrow gap and a narrow track width can be accommodated.
[0139]
Further, a bias underlayer and a bias layer are laminated via an amorphous conductive layer, and this amorphous conductive layer fulfills the function of raising the bias underlayer and the bias layer. However, the bias layer formed on the bias underlayer can be formed at a high position in both side regions of the multilayer resistance film, and can be opposed to the both sides of the free magnetic layer with a sufficient volume.
[0140]
Furthermore, even if the amorphous conductive layer remains at the interface between the multilayer resistive film, the bias underlayer and the bias layer, it has conductivity, so that the junction resistance does not increase and the characteristics of the magnetic head deteriorate. Can be prevented.
[0141]
In addition, the sense current flows in the vicinity of the free magnetic layer / nonmagnetic layer / pinned magnetic layer of the multilayer resistive film, so that the output can be improved by reducing the shunt loss.
[0142]
Furthermore, in the step of forming the amorphous conductive layer, even if the amorphous conductive layer adheres to the bias underlayer and the region to which the bias layer is to be bonded in both sides of the multilayer resistive film, the amorphous conductive layer has conductivity. It is not necessary to completely remove the amorphous conductive layer, and it is possible to prevent the multilayer resistance film from being damaged by the etching process.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of a magnetic detection element according to a first embodiment of the present invention as viewed from a surface facing a recording medium.
2 is an enlarged partial sectional view of a right side shape of the magnetic detection element shown in FIG.
FIG. 3 is an enlarged partial cross-sectional view of a right side shape of a magnetic detection element according to a second embodiment of the present invention.
FIG. 4 is a partial cross-sectional view of a magnetic detection element according to a third embodiment of the present invention as viewed from the side facing a recording medium.
FIG. 5 is a partial cross-sectional view of a magnetic detection element according to a fourth embodiment of the present invention as viewed from the side facing a recording medium.
6 is a cross-sectional view showing a method of manufacturing the magnetic sensing element shown in FIG. 1 in the order of steps.
7 is a cross-sectional view showing a method of manufacturing the magnetic sensing element shown in FIG. 1 in the order of steps.
8 is a cross-sectional view showing a method of manufacturing the magnetic sensing element shown in FIG. 1 in the order of steps.
9 is a cross-sectional view showing a method of manufacturing the magnetic sensing element shown in FIG. 1 in the order of steps.
10 is a cross-sectional view showing a method of manufacturing the magnetic sensing element shown in FIG. 1 in the order of steps.
11A is a diagram showing the relationship between the Cr deposition angle of the bias underlayer and the XRD peak ratio of CoPt of the bias layer, and FIG. 11B is a diagram showing the relationship between FIG. FIG. 11C is a graph showing the relationship between the XRD peak ratio of CoPt of the bias layer and the coercive force (Hc) of the bias layer made of CoPt. 11 (d) is a graph showing the numerical values shown in FIG. 11 (c).
12A is an orientation state when the Cr film formation angle is 20 °, FIG. 12B is an orientation state when the Cr film formation angle is 50 °, and FIG. It is a figure which shows by multiple recording the orientation dependence of CoPt and the dependence of the coercive force Hc of CoPt on the film forming angle of Cr.
FIG. 13 is a partial cross-sectional view of a conventional magnetic detection element as seen from the side facing the recording medium.
FIG. 14 is a partial cross-sectional view of a conventional magnetic detection element as viewed from the side facing the recording medium.
[Explanation of symbols]
20 Multilayer resistive film
21 Lower shield layer
22 Lower gap layer
25 Seed layer
26 Antiferromagnetic layer
27 Fixed magnetic layer
28 Nonmagnetic conductive layer
29 Free magnetic layer
30 protective layer
32 Amorphous conductive layer
33 Bias underlayer
34 Hard bias layer
36 Electrode layer
46 Multilayer resistive film

Claims (15)

A gap layer formed on a substrate, a multilayer resistance film formed by sequentially laminating at least an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer on the gap layer; and the multilayer resistance film A magnetic sensing element including a bias underlayer and a bias layer formed on both sides of the free magnetic layer, the nonmagnetic conductive layer, and the pinned magnetic layer,
The antiferromagnetic layer has at least two side regions extending outward from both side end surfaces of the free magnetic layer, the nonmagnetic conductive layer, and the pinned magnetic layer of the multilayer resistive film ,
An amorphous conductive layer is formed on both sides of the antiferromagnetic layer, and the bias underlayer and the bias layer are sequentially stacked on the amorphous conductive layer,
The bias layer, the anti-side portions of the ferromagnetic layers, the amorphous conductive layer and is raised by the bias underlayer, magnetic sensing element, characterized in that opposite the side end surface of the free magnetic layer. The magnetic detection element according to claim 1,
The magnetic detecting element, wherein the bias underlayer is formed of a crystal structure having a bcc structure, and at least a [211] plane or a [200] plane is oriented in a direction perpendicular to the film plane. The magnetic detection element according to claim 1,
The magnetic detection element, wherein the bias layer is formed of a magnetic material having at least a [100] plane preferentially oriented in a direction perpendicular to the film plane. The magnetic detection element according to claim 2,
The magnetic sensing element, wherein the bias underlayer is interposed between the bias layer and the free magnetic layer. The magnetic detection element according to claim 1,
The magnetic sensing element, wherein the amorphous conductive layer is a nonmagnetic material. The magnetic detection element according to claim 1,
The amorphous conductive layer is formed of a Co-TZ alloy, T is an element including at least one of Zr and Hf, and Z is an element including at least one of Ta and Nb. Magnetic sensing element The magnetic detection element according to claim 1,
The magnetic sensing element, wherein the amorphous conductive layer is made of a Ni-X alloy, and X is made of an element containing at least P. The magnetic detection element according to claim 1,
In the antiferromagnetic layer, the film thickness of the both side regions is smaller than the film thickness of the region in contact with the pinned magnetic layer between the both side regions, and the amorphous conductive layer is on both side regions of the antiferromagnetic layer. A magnetic detecting element having a desired film thickness. The magnetic detection element according to claim 8, wherein
The magnetic sensing element, wherein the amorphous conductive layer has a thickness of 60 to 300 mm. The magnetic detection element according to claim 1,
The magnetic detection element, wherein the pinned magnetic layer includes a pair of ferromagnetic layers formed with a nonmagnetic intermediate layer interposed therebetween, and the magnetization directions of the pair of ferromagnetic layers are antiparallel to each other. The magnetic detection element according to claim 1,
A magnetic sensing element, wherein a seed layer is formed between the gap layer and the antiferromagnetic layer. The magnetic detection element according to claim 1,
The magnetic detection element, wherein the free magnetic layer includes a pair of ferromagnetic layers formed with a nonmagnetic intermediate layer interposed therebetween, and the magnetization directions of the pair of ferromagnetic layers are antiparallel to each other. Forming a multilayer resistive film on the gap layer of the substrate by laminating at least an antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic conductive layer, and a free magnetic layer in order ;
Patterning the multilayer resistive film by etching and overetching both sides of the antiferromagnetic layer; and
Forming an amorphous conductive layer on the over-etched regions on both sides of the antiferromagnetic layer;
Forming a bias underlayer on the amorphous conductive layer;
And a step of forming a bias layer on the bias underlayer. In the manufacturing method of the magnetic sensing element according to claim 13,
In the step of forming the bias underlayer, the film forming angle of the bias underlayer made of the bcc structure crystal structure is controlled so that at least the [211] plane or the [200] plane is oriented in the direction perpendicular to the film plane. Thus, the method of manufacturing a magnetic sensing element is characterized in that the bias underlayer is formed. In the manufacturing method of the magnetic sensing element according to claim 13,
In the step of forming the bias layer, the bias layer is formed by controlling the film formation angle of the bias layer to an angle at which the [100] plane is oriented in the direction perpendicular to the film surface. Manufacturing method of magnetic detection element.

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