JP2010080535A - Magnetoresistance effect element, magnetic head and magnetic recording and reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new magnetoresistance effect element capable of reducing a spin transfer torque and outputting a sufficient reproduction output even at a relatively small MR rate, and a magnetic head and a magnetic recording and reproducing apparatus using the magnetoresistance effect element. <P>SOLUTION: The magnetoresistance effect element includes a magnetization fixed layer where a magnetization direction is fixed practically in one direction, a magnetization free layer where the magnetization direction is changed corresponding to an external magnetic field, a magnetoresistance effect film provided between the magnetization fixed layer and the magnetization free layer and provided with a composite spacer layer including an insulating layer and a ferromagnetic metal layer passing through the insulating layer, and a pair of electrode layers provided on the upper surface and the lower surface along the thickness direction of the magnetoresistance effect film. To form this magnetoresistance effect element, a sense current is made to flow from the magnetization fixed layer of the magnetoresistance effect film to the magnetization free layer through the pair of electrode layers. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a magnetoresistive effect element, a magnetic head, and a magnetic recording / reproducing apparatus.

  Magnetoresistive effect elements are used as magnetic field sensors and magnetic heads (MR heads). The MR head is mounted on a magnetic recording / reproducing apparatus and reads information from a magnetic recording medium such as a hard disk drive. In this hard disk or the like, a reproducing element using a film having a spin valve structure is generally used.

  The spin valve film is a multilayer film having a sandwich structure in which a nonmagnetic layer is sandwiched between two ferromagnetic layers. One of the ferromagnetic layers has its magnetization direction fixed by an exchange bias magnetic field from the antiferromagnetic layer, and is called a “pinned layer” or “magnetization pinned layer”. The other ferromagnetic layer can be rotated in its magnetization direction by an external magnetic field (signal magnetic field or the like), and is also referred to as a “free layer” or a “magnetization free layer”. The nonmagnetic layer is referred to as a “spacer layer” or “intermediate layer”.

  Such a spin valve film can obtain a large magnetoresistance effect by changing the relative angle of the magnetization directions of these two ferromagnetic layers by an external magnetic field.

  Magnetoresistance effect elements using a spin valve film include a CIP (Current-in-Plane) type and a CPP (Current Perpendicular to Plane) type. In the former, a sense current flows in a direction parallel to the film surface of the spin valve film, and in the latter, a sense current flows in a direction perpendicular to the film surface of the spin valve film. Previously, the CIP type was used, but CPP type magnetic heads are now widely used because of the need for output voltage and spatial resolution.

  At present, magnetic heads using the CPP type TMR effect (tunneling magneto resistive effect) are common, but in order to further improve the performance (recording density) of the hard disk, a head with high output and low resistance is required, and such a head is used. Spin valve films other than the CPP-type TMR effect including the CPP-type GMR effect (giant magneto resistive effect) have also been studied. Among them, regarding the MR effect with the domain wall MR effect and the magnetic metal junction, a magnetoresistive effect with a high magnetoresistance change rate has been observed using a fine junction between Ni thin wires (see Non-Patent Document 1). As a film that can be applied as an actual head, a spin valve film having a magnetic metal junction has also been reported (see Non-Patent Document 2).

  In a spin valve film having a magnetic metal junction, for example, an insulating layer including a minute metal layer is inserted between the above-described magnetization free layer and the pinned layer, whereby the magnetization free layer and the pinned layer are separated from each other. A three-dimensional structure of magnetic micro-coupling is provided between them, and the MR effect due to spin-dependent scattering by the domain wall in the magnetic coupling is used.

  Development of a magnetoresistive effect element in which the above-described magnetic micro-coupling is developed into a three-dimensional structure is underway, and Patent Document 1 discloses EB (Electron Beam) as a method for producing a nanocontact in a three-dimensional direction, that is, as a hole-piercing method. ) An irradiation process, an FIB (Focused Ion Beam) irradiation process, an AFM (Atomic Force Microscope) technique, and the like are disclosed.

Phys. Rev. Lett. 82 2923 (1999) IEEE Trans. Magn. 43 2848 (2007) JP 2003-204095 A

  In order for the magnetoresistive film having the spin valve structure to function as a reproducing element, a bias current (sense current) is passed substantially perpendicularly to the film surface. At this time, by flowing the bias current, conduction electrons also flow in the opposite direction to the bias current. At this time, the spin angular momentum of the magnetic film that first passes through the spin angular momentum of the conduction electrons. Next, it flows into the passing magnetic film and gives torque to its magnetization.

  For example, when the conduction electrons flow from the magnetization fixed layer to the magnetization free layer, the angular momentum when passing through the magnetization fixed layer gives a torque to the magnetization in the magnetization free layer. In addition, when the conduction electrons flow from the magnetization free layer to the magnetization pinned layer, the angular momentum when passing through the magnetization free layer gives torque to the magnetization in the magnetization pinned layer.

  The torque generated as described above is so-called spin transfer torque. This spin transfer torque is actively used for memory recording, such as MRAM (Magnetic Random Access Memory). However, for the reproducing element used in the above-mentioned hard disk or the like, the spin transfer torque is large in the magnetization of the magnetization free layer. In some cases, the magnetoresistive film has a large noise. This will be described below.

  The transfer efficiency of the spin torque greatly depends on the direction of the current and the relative angle between the magnetization free layer magnetization and the magnetization pinned layer magnetization. When the bias current flows from the magnetization free layer to the magnetization fixed layer (conduction electrons from the magnetization fixed layer to the magnetization free layer), the transfer efficiency is improved when the relative angle of magnetization of both layers is close to 180 degrees. On the other hand, when a bias current flows from the magnetization fixed layer to the magnetization free layer (conduction electrons flow from the magnetization free layer to the magnetization fixed layer), the transfer efficiency is improved when the relative angle of magnetization of both layers is close to 0 degrees.

  In the former case, the conduction electron spin is parallel to the magnetization of the magnetization pinned layer and antiparallel to the magnetization of the magnetization free layer, and the conduction electron having a spin parallel to the magnetization of the magnetization pinned layer This is because it passes through and reaches the magnetization free layer. In the latter case, the spin of the conduction electron is parallel to the magnetization of the magnetization pinned layer and the magnetization free layer, but the conduction electron having a spin antiparallel to the magnetization of the magnetization pinned layer is reflected by the magnetization pinned layer. This is to enter the magnetization free layer.

  As described above, the magnetization of the magnetization free layer is subjected to torque caused by the spin taken into the magnetization free layer as described above, and therefore, the magnetization of the magnetization free layer is unstable and unstable. As a result, there is a case where the reproduction output is not sufficiently output due to noise. Therefore, if the direction in which the bias current flows is changed in consideration of the relative angle between the magnetization free layer magnetization and the magnetization pinned layer magnetization, and the spin torque delivery efficiency is reduced, the spin torque delivery efficiency described above is improved to some extent. Can be reduced.

  However, the spin transfer torque described above also depends on the bias current value and becomes conspicuous as the bias current value increases. Therefore, the spin transfer torque is simply changed by changing the direction in which the bias current flows as described above. The influence of torque cannot be reduced sufficiently.

On the other hand, if the bias current value is reduced, the spin transfer torque can be reduced without considering the direction in which the bias current flows. Specifically, if the order is 10 ⁷ (A / cm ² ) or less, the influence of the spin transfer torque can be reduced.

However, the bias current value is greatly related to the characteristics required of the magnetoresistive effect element, and if the bias current value increases, a large reproduction output can be obtained even if the MR ratio of the magnetoresistive effect element is small. Therefore, when the bias current value is on the order of 10 ⁷ (A / cm ² ) or less, it is required that the MR ratio of the magnetoresistive element is sufficiently high in order to obtain a sufficient reproduction output. Such TMR and GMR cannot satisfy such MR ratio.

  The present invention relates to a novel magnetoresistive element capable of reducing spin transfer torque and outputting a sufficient reproduction output even with a relatively small MR ratio, and a magnetic head and a magnetic recording / reproducing using the magnetoresistive element An object is to provide an apparatus.

  In order to achieve the above object, one embodiment of the present invention includes a magnetization pinned layer in which the magnetization direction is substantially pinned in one direction, a magnetization free layer in which the magnetization direction changes in response to an external magnetic field, and the magnetization pinned A magnetoresistive effect film having a composite spacer layer including an insulating layer and a ferromagnetic metal layer penetrating the insulating layer, and provided along the thickness direction of the magnetoresistive effect film. A pair of electrode layers provided on the upper and lower surfaces, and configured to cause a sense current to flow from the magnetization fixed layer to the magnetization free layer of the magnetoresistive effect film via the pair of electrode layers. The present invention relates to a magnetoresistive effect element.

  Another aspect of the present invention relates to a magnetic head comprising the magnetoresistive element.

  Furthermore, another aspect of the present invention relates to a magnetic recording / reproducing apparatus comprising a magnetic recording medium and the magnetic head.

  According to the above aspect, it is possible to provide a novel magnetoresistive element capable of reducing spin transfer torque and outputting sufficient reproduction output even with a relatively small MR ratio.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Magnetoresistive element)
FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a magnetoresistive element according to an embodiment of the present invention.

  The magnetoresistive effect element 10 shown in FIG. 1 has a lower electrode LE and an upper electrode UE, and a laminated film is disposed between them. This laminated film is composed of a base layer 11, an antiferromagnetic layer 12, a composite pinned layer (magnetization pinned layer) 13 (a pinned layer 131, a magnetization antiparallel coupling layer 132, and a pinned layer 133), a composite spacer layer on the lower electrode LE. 14, a free layer (magnetization free layer) 15, and a protective layer 16 are sequentially laminated. Here, the composite pinned layer 13, the composite spacer layer 14, and the free layer 15 constitute a spin valve film.

  The lower electrode LE and the upper electrode UE are for applying a sense current in a direction substantially perpendicular to the spin valve film, and the magnetoresistive element 10 is a CPP (flow sensor) that allows the sense current to flow in a direction perpendicular to the element film surface. (Current Perpendicular to Plane) type magnetoresistive effect element is constructed.

The underlayer 11 can have, for example, a two-layer structure of a buffer layer 11a and a seed layer 11b. The buffer layer 11a is a layer for reducing the roughness of the surface of the lower electrode LE. For example, Ta, Ti, W, Zr, Hf, Cr, or an alloy thereof can be used. The seed layer 11b is a layer for controlling the crystal orientation of the spin valve film, for _{example, Ru, (Fe x Ni 100} -x) 100-y X y (X = Cr, V, Nb, Hf, Zr, Mo, 15 <x <25, 20 <y <45) can be used.

  The thickness of the buffer layer 11a is preferably about 2 to 10 nm, and more preferably about 3 to 5 nm. If the buffer layer 11a is too thin, the buffer effect is lost. The film thickness of the seed layer 12b is preferably 1 to 5 nm and more preferably 1.5 to 3 nm in order to sufficiently exhibit the function of improving the crystal orientation.

  The antiferromagnetic layer 12 is made of an antiferromagnetic material (for example, PtMn, PdPtMn, IrMn, RuRhMn) having a function of imparting unidirectional anisotropy to the composite pinned layer 13 and fixing magnetization. .

  In order to provide sufficient unidirectional anisotropy, the film thickness of the antiferromagnetic layer 12 is appropriately set. When the material of the antiferromagnetic layer 12 is PtMn or PdPtMn, the thickness is preferably about 8 to 20 nm, and more preferably 10 to 15 nm. When the material of the antiferromagnetic layer 12 is IrMn, unidirectional anisotropy can be imparted even with a thinner film thickness such as PtMn, preferably 3 to 12 nm, more preferably 4 to 10 nm.

  The composite pinned layer (magnetization pinned layer) 13 has two ferromagnetic films (here, pinned layers 131 and 133) in which the magnetization direction is substantially pinned, and a magnetization antireflection layer disposed between them. The parallel coupling layer 132 is configured. A single pinned layer can be used instead of the composite pinned layer 13. The upper and lower pinned layers 131 and 133 of the magnetization antiparallel coupling layer 132 are magnetically coupled via the magnetization antiparallel coupling layer 132 so that the magnetization directions are antiparallel to each other.

  The pinned layers 131 and 133 are made of a ferromagnetic material (for example, Fe, Co, Ni, FeCo alloy, FeNi alloy). The magnetization antiparallel coupling layer 132 is for antiferromagnetic coupling of the pinned layers 131 and 133, and for example, Ru, Ir, Rh is used.

  The thickness of the magnetic layer used for the pinned layer 131 is preferably about 1.5 to 4 nm. This is based on the viewpoint of the unidirectional anisotropic magnetic field strength by the anti-antiferromagnetic layer 12 (for example, IrMn) and the antiferromagnetic coupling field strength to the pinned layer 133 through the magnetic coupling layer 132 (for example, Ru). . If the pinned layer 131 is too thin, the MR change rate becomes small. On the other hand, if the pinned layer 131 is too thick, it is difficult to obtain a sufficient unidirectional anisotropic magnetic field necessary for device operation. For the same reason, the thickness of the magnetic layer used for the pinned layer 133 is preferably about 1.5 to 4 nm.

  The composite spacer layer 14 includes an insulating layer 141 and a ferromagnetic metal layer (ferromagnetic metal portion) 142.

  As the insulating layer 141, a material having a function of insulating current can be used as appropriate. Specifically, Al, Mg, Li, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Se, Sr, Y, Zr, Nb, Mo, Pd , Ag, Cd, In, Sn, Sb, Ba, Ka, Hf, Ta, W, Re, Pt, Hg, Pb, Bi, oxides containing at least one of lanthanoid elements, nitrides, oxynitrides, carbides, etc. It can consist of

  Since the insulating layer 141 also has a function as a spacer of the pinned layer 133 and the free layer 15, the thickness is preferably 1 to 3.5 nm, and more preferably 1.5 to 3 nm.

  The ferromagnetic metal layer 142 is a path through which a current flows in the direction perpendicular to the composite spacer layer 14, and a metal layer made of a ferromagnetic material such as Fe, Co, Ni, or an alloy can be used.

  The free layer 15 is made of a ferromagnetic material (for example, Fe, Co, Ni, FeCo alloy, FeNi alloy) in the same manner as the pinned layer 131 described above.

  The protective layer 16 is for protecting the spin valve film, and can have a plurality of metal layers, for example, a two-layer structure of a Cu layer and a Ru layer (Cu [1 nm] / Ru [10 nm]). . As the protective layer 16, a Ru / Cu layer in which Ru is disposed on the free layer 15 side or the like can also be used. In this case, the film thickness of Ru is preferably about 0.5 to 2 nm. The protective layer 16 having this configuration is particularly desirable when the free layer 15 is made of NiFe. This is because Ru has a non-solid relationship with Ni, so that magnetostriction of the interface mixing layer formed between the free layer 15 and the protective layer 16 can be reduced.

  In addition, the magnetoresistive effect element of this aspect can be manufactured by a general purpose method. In particular, when forming the composite spacer layer 14, for example, the first metal layer and the second metal layer constituting the ferromagnetic metal layer 142 are sequentially formed, and then surface oxidation treatment or surface nitridation treatment is performed. Then, a part of the first metal layer is allowed to penetrate into the second metal layer, and the second metal layer is converted into an insulating layer. Specifically, it is carried out based on a technique as disclosed in JP-A-2006-54257.

(Regeneration of magnetoresistive effect element)
Next, the reproduction principle of the magnetoresistive element 10 in the above aspect will be described. 2 and 3 are diagrams for explaining the reproduction principle, and show the pinned layer 133, the composite spacer layer 14, and the free layer 15 in an enlarged manner.

  In this aspect, as shown in FIG. 1, a current is passed from the pinned layer 133 toward the free layer 15 through the magnetoresistive effect element 10. Therefore, conduction electrons flow from the free layer 15 toward the pinned layer 133.

  As shown in FIG. 2, when the magnetization M1 of the pinned layer 133 and the magnetization M2 of the free layer 15 are parallel to each other (in this embodiment, upward to each other), that is, when the relative angle between the magnetizations M1 and M2 is 0 degree, A domain wall does not occur in the ferromagnetic metal layer 142. Therefore, since the conduction electrons E1 and E2 flowing from the free layer 15 pass through the ferromagnetic metal layer 142 as they are and flow into the pinned layer 133, the spin torque transfer efficiency in the free layer 15 is lowered.

  On the other hand, when the magnetization M1 of the pinned layer 133 and the magnetization M2 of the free layer 15 deviate from parallel, a domain wall DW is formed in the ferromagnetic metal layer 142 of the composite spacer layer 14. A magnetization m1 in the same direction as the magnetization M1 is generated on the pinned layer 133 side of the domain wall DW, and a magnetization m2 in the same direction as the magnetization M2 is generated on the free layer 142 side of the domain wall DW. For this reason, the domain wall DW comes to function as a reflective layer with respect to the conduction electrons E1 and E2.

  For example, the spin directions of the conduction electrons E1 and E2 introduced into the free layer 15 are different from the direction of the magnetization m1 of the domain wall DW on the pinned layer 133 side, so that the conduction electrons E1 and E2 are in the domain wall DW. It becomes reflected. Accordingly, the spin torque delivery efficiency of the free layer 15 is increased.

  However, as shown in FIG. 3, when the magnetization M1 of the pinned layer 133 and the magnetization M2 of the free layer 15 are antiparallel (in this embodiment, the magnetization M1 is upward and the magnetization M2 is downward), the magnetization is introduced into the free layer 15. Of the conducted electrons E1 and E2, the conducted electrons E1 having a spin in the same direction as the magnetization m1 on the pinned layer 133 side of the domain wall DW are transmitted without being reflected by the domain wall DW. On the other hand, the conduction electron E2 having a spin in the direction opposite to the direction of the magnetization m1 is reflected by the domain wall DW, but the spin direction is the same as the direction of the magnetization M2 of the free layer 15.

  Accordingly, no substantial spin torque is transferred in the free layer 15. Therefore, the delivery efficiency of the spin torque is reduced.

  According to this embodiment, the magnetization of the pinned layer 133 is caused by flowing current from the pinned layer 133 toward the free layer 15 to the magnetoresistive effect element 10, that is, by flowing conduction electrons from the free layer 15 toward the pinned layer 133. When M1 and the magnetization M2 of the free layer 15 are parallel or antiparallel, the delivery efficiency of the spin torque becomes sufficiently small.

  FIG. 4 shows the spin torque delivery efficiency (noise intensity due to spin torque) and the relative angular dependence of the magnetizations M2 and M1 in the free layer 15 and the pinned layer 133 in this embodiment.

  As is clear from FIG. 4, the spin torque delivery efficiency (noise intensity due to the spin torque) is slightly increased near the relative angle of 90 degrees, but as the angle approaches 0 degrees (parallel) and 180 degrees (antiparallel), It can be seen that the delivery efficiency of spin torque (noise intensity caused by spin torque) decreases. This graph is based on simulation.

  Therefore, the output waveform of the magnetoresistive effect element 10 that satisfies the requirements in this way is a good sine curve as shown in FIG. 5, for example. On the other hand, when the spin torque delivery efficiency (noise intensity due to the spin torque) is high, for example, a curve as indicated by a broken line in the figure is obtained, and a good output voltage may not be obtained.

(Application of magnetoresistive effect element)
Hereinafter, application of the magnetoresistive effect element (CCP-CPP element) according to the embodiment of the present invention will be described.

(Magnetic head)
6 and 7 show a state in which the magnetoresistive effect element according to the embodiment of the present invention is incorporated in a magnetic head. FIG. 6 is a cross-sectional view of the magnetoresistive element cut in a direction substantially parallel to a medium facing surface facing a magnetic recording medium (not shown). FIG. 7 is a cross-sectional view of the magnetoresistive element cut in a direction perpendicular to the medium facing surface ABS.

  The magnetic head illustrated in FIGS. 6 and 7 has a so-called hard abutted structure. A lower electrode LE and an upper electrode UE are provided above and below the magnetoresistive film 10, respectively. In FIG. 6, a bias magnetic field application film 41 and an insulating film 42 are laminated on both sides of the magnetoresistive film 10. As shown in FIG. 7, a protective layer 43 is provided on the medium facing surface of the magnetoresistive film 10.

  The sense current for the magnetoresistive film 10 is energized in a direction substantially perpendicular to the film surface as indicated by the arrow A by the lower electrode LE and the upper electrode UE disposed above and below the magnetoresistive effect film 10. A bias magnetic field is applied to the magnetoresistive film 10 by a pair of bias magnetic field application films 41, 41 provided on the left and right. By this bias magnetic field, the magnetic anisotropy of the free layer 15 of the magnetoresistive effect film 10 is controlled to form a single magnetic domain, thereby stabilizing the magnetic domain structure and suppressing Barkhausen noise accompanying the domain wall movement. can do. Since the S / N ratio of the magnetoresistive film 10 is improved, high sensitivity magnetic reproduction is possible when applied to a magnetic head.

(Hard disk and head gimbal assembly)
The magnetic head shown in FIGS. 6 and 7 can be incorporated into a recording / reproducing integrated magnetic head assembly and mounted on a magnetic recording / reproducing apparatus.

  FIG. 8 is a main part perspective view illustrating a schematic configuration of such a magnetic recording / reproducing apparatus. That is, the magnetic recording / reproducing apparatus 150 of this embodiment is an apparatus of a type using a rotary actuator. In the figure, a magnetic disk 200 is mounted on a spindle 152 and rotated in the direction of arrow A by a motor (not shown) that responds to a control signal from a drive device control unit (not shown). The magnetic recording / reproducing apparatus 150 of this embodiment may include a plurality of magnetic disks 200.

  A head slider 153 that records and reproduces information stored in the magnetic disk 200 is attached to the tip of a thin-film suspension 154. The head slider 153 has a magnetic head including the magnetoresistive effect element according to any one of the above-described embodiments mounted near its tip.

  When the magnetic disk 200 rotates, the medium facing surface (ABS) of the head slider 153 is held with a predetermined flying height from the surface of the magnetic disk 200. Alternatively, a so-called “contact traveling type” in which the slider contacts the magnetic disk 200 may be used.

  The suspension 154 is connected to one end of the actuator arm 155. A voice coil motor 156, which is a kind of linear motor, is provided at the other end of the actuator arm 155. The voice coil motor 156 includes a drive coil (not shown) wound around a bobbin portion, and a magnetic circuit including a permanent magnet and a counter yoke arranged so as to sandwich the coil.

  The actuator arm 155 is held by ball bearings (not shown) provided at two positions above and below the spindle 157, and can be freely rotated and slid by a voice coil motor 156.

  FIG. 9 is an enlarged perspective view of the head gimbal assembly ahead of the actuator arm 155 as viewed from the disk side. That is, the assembly 160 has an actuator arm 155, and a suspension 154 is connected to one end of the actuator arm 155. A head slider 153 including a magnetic head including the magnetoresistive effect element according to any one of the above-described embodiments is attached to the tip of the suspension 154. The suspension 154 has a lead wire 164 for writing and reading signals, and the lead wire 164 and each electrode of the magnetic head incorporated in the head slider 153 are electrically connected. In the figure, reference numeral 165 denotes an electrode pad of the assembly 160.

  According to the present embodiment, by providing the magnetic head including the magnetoresistive element described above, it is possible to reliably read information magnetically recorded on the magnetic disk 200 at a high recording density.

(Other embodiments)
Embodiments of the present invention are not limited to the above-described embodiments, and can be expanded and modified. The expanded and modified embodiments are also included in the technical scope of the present invention. The specific structure of the magnetoresistive film, and other shapes and materials of the electrode, bias application film, insulating film, etc., are appropriately implemented by those skilled in the art, and the present invention is similarly implemented. The effect of can be obtained. For example, when applying a magnetoresistive element to a reproducing magnetic head, the detection resolution of the magnetic head can be defined by providing magnetic shields above and below the element.

  The embodiment of the present invention can be applied not only to a longitudinal magnetic recording system but also to a perpendicular magnetic recording system magnetic head or magnetic reproducing apparatus. Furthermore, the magnetic reproducing apparatus of the present invention may be a so-called fixed type having a specific recording medium constantly provided, or a so-called “removable” type in which the recording medium can be replaced.

  In addition, all magnetoresistive elements, magnetic heads, magnetic storage / reproduction devices, and magnetic memories that can be appropriately designed and implemented by those skilled in the art based on the magnetic head and magnetic storage / reproduction device described above as embodiments of the present invention Are also within the scope of the present invention.

It is a typical sectional view showing a schematic structure of a magnetoresistive effect element concerning an embodiment. It is a figure explaining the reproduction | regeneration principle of the magnetoresistive effect element concerning embodiment. Similarly, it is a figure explaining the reproduction | regeneration principle of the magnetoresistive effect element concerning embodiment. It is a graph which shows the relative angle dependence of the magnetization in the free layer and the pin layer 133, and the delivery efficiency (noise intensity resulting from a spin torque) concerning the embodiment. It is a graph which shows the output voltage of the magnetoresistive effect element concerning embodiment. It is a figure which shows the state which incorporated the magnetoresistive effect element concerning embodiment into the magnetic head. Similarly, it is a figure which shows the state which incorporated the magnetoresistive effect element based on Embodiment in the magnetic head. It is a principal part perspective view which illustrates schematic structure of a magnetic recording / reproducing apparatus. It is the expansion perspective view which looked at the head gimbal assembly ahead from an actuator arm from the disk side.

  DESCRIPTION OF SYMBOLS 10 ... Magnetoresistance effect film, LE ... Lower electrode, 11 ... Underlayer, 11a ... Buffer layer, 11b ... Seed layer, 12 ... Antiferromagnetic layer, 13 ... Composite pin layer, 131, 133 ... Pin layer, 132 ... Magnetization Anti-parallel coupling layer, 15 ... free layer, 16 ... protective layer

Claims (6)

A magnetization pinned layer in which the magnetization direction is substantially pinned in one direction;
A magnetization free layer whose magnetization direction changes in response to an external magnetic field;
A magnetoresistive film having a composite spacer layer provided between the magnetization pinned layer and the magnetization free layer and including an insulating layer and a ferromagnetic metal layer penetrating the insulating layer;
A pair of electrode layers provided on the upper and lower surfaces along the thickness direction of the magnetoresistive film,
A magnetoresistive effect element configured to cause a sense current to flow from the magnetization fixed layer to the magnetization free layer of the magnetoresistive effect film through the pair of electrode layers.   The magnetoresistive effect element according to claim 1, wherein the insulating layer contains at least one selected from the group consisting of oxygen, nitrogen, and carbon.   The magnetoresistive element according to claim 1, wherein the metal portion includes at least one of Fe and Co.   4. The magnetism according to claim 1, wherein at least one of the magnetization pinned layer and the magnetization free layer includes at least one selected from the group consisting of Fe, Co, and Ni. 5. Resistive effect element.   A magnetic head comprising the magnetoresistive effect element according to claim 1.   A magnetic recording / reproducing apparatus comprising a magnetic recording medium and the magnetic head according to claim 5.

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