JP2007201059A - Magnetic element, magnetic recording equipment, and writing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce variation in element characteristics due to micro working. <P>SOLUTION: The magnetic element comprises a first magnetic layer FP of which magnetization direction is fitted, and a first region 20 with variable magnetization direction arranged opposite to the first magnetic layer FP. It is also provided with: a second magnetic layer FF formed from conductive material, with a larger width than the first magnetic layer parallel to a film surface; and a first nonmagnetic layer SP formed from nonconductive material, and provided between the first magnetic layer FP and the second magnetic layer FF. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a magnetic element, a magnetic recording apparatus, and a writing method having a thin wire-shaped magnetic layer.

  In recent years, as a presence that supports and leads a wide and highly informatized society, information recording technology that satisfies various requirements has been demanded. Magnetic recording devices using the magnetic moment of a ferromagnetic material are widely used as, for example, hard disk drives, and proposed to be used as magnetic random access memories (MRAMs) that have both high speed and non-volatility. Has been.

  In the magnetic random access memory, there is a strong demand for high density. In the future, if it becomes necessary to reduce the unit cell for storing 1-bit data from 100 nanometers to several tens of nanometers, the current mainstream magnetic field writing method will increase the write current and the adjacent cells. It is expected that we will face problems such as crosstalk. Therefore, as an alternative to this magnetic field writing method, there is an increasing expectation for a writing method using a spin transfer phenomenon via current. This writing method is based on the physical basis of the transfer of angular momentum (spin transfer) from the spin of conduction electrons to the local magnetic moment of the magnetic material. The smaller the cell size compared to the magnetic field writing method, It has the feature that the write current can be reduced.

  A conventional magnetic element of a spin transfer writing system represented by Non-Patent Document 1 has a columnar shape. That is, a laminated film composed of a magnetization pinned magnetic layer (hereinafter referred to as a pinned layer), an intermediate layer, and a magnetization free magnetic layer (hereinafter referred to as a recording layer) is patterned into a dot shape of several tens to several hundreds of nanometers. Writing and reading are performed by passing a current perpendicular to the.

However, it is not easy to suppress variation in write current in a magnetic element using a conventional spin transfer write method. This is due to the fact that the recording layer must be processed into a uniform dot shape.
FJAlbert et al., Appl. Phys. Lett., 77, 3809 (2000)

  The present invention provides a magnetic element, a magnetic recording apparatus, and a writing method capable of reducing variations in element characteristics due to microfabrication.

  A magnetic element according to a first aspect of the present invention includes a first magnetic layer having a fixed magnetization direction, and a first region having a variable magnetization direction disposed to face the first magnetic layer. A second magnetic layer having a larger width than the first magnetic layer in a direction parallel to the film surface and formed of a conductive material; the first magnetic layer; and the second magnetic layer And a first nonmagnetic layer formed of a nonconductive material.

  According to a second aspect of the present invention, there is provided a magnetic element writing method comprising: a first magnetic layer having a fixed magnetization direction; and a first magnetization layer disposed opposite to the first magnetic layer and having a variable magnetization direction. A second magnetic layer including a region and a second region, having a width greater than that of the first magnetic layer in a direction parallel to the film surface, and formed of a conductive material; and A first nonmagnetic layer formed between the magnetic layer and the second magnetic layer and made of a non-conductive material, wherein the magnetization of the first magnetic layer and the first region When the magnetization is in the first magnetization arrangement, a first current is passed between the first magnetic layer and the second magnetic layer, and the magnetization of the first region is set in the first direction. A step of setting the first magnetization arrangement toward the first magnetization layer, and setting the magnetization of the first magnetic layer and the magnetization of the first region to a second magnetization arrangement. A magnetic domain including the first region by setting the direction of magnetization of the second region and passing a second current in a direction parallel to the film surface of the second magnetic layer. Moving the domain wall of the first region in the second magnetic layer, and setting the magnetization of the first region to the second magnetization arrangement in a direction corresponding to the direction of the magnetization of the second region Including.

  ADVANTAGE OF THE INVENTION According to this invention, the magnetic element which can reduce the dispersion | variation in the element characteristic by microfabrication, a magnetic recording apparatus, and the writing method can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description, common parts are denoted by common reference symbols throughout the drawings.

[1] First Embodiment [1-1] Structure FIG. 1 is a diagram schematically showing a cross-sectional structure of a magnetic element according to a first embodiment of the present invention. 2A and 2B are diagrams schematically showing a planar structure of the magnetic element according to the first embodiment of the present invention. The structure of the magnetic element according to the first embodiment of the present invention will be described below.

  As shown in FIG. 1, the magnetic element 10 is a magnetoresistive effect element such as an MTJ (Magnetic Tunnel Junction) element. The magnetic element 10 has a multilayer structure in which a recording layer (magnetic layer) FF, an intermediate layer (nonmagnetic layer) SP, and a fixed layer (magnetic layer) FP are sequentially stacked.

The recording layer FF includes a storage area 20 whose magnetization direction is variable and has a thin line shape. This fine line shape means that the dimension (width W _FFX ) in the X direction (parallel to the film surface) is one digit or more relative to the dimension in the Y direction perpendicular to the X direction and the dimension (film thickness) in the Z direction. Point to a large shape. Hereinafter, this X direction is referred to as a fine line direction. The width W _{FFX in} the fine line direction of the recording layer FF is larger than the width W _{FPX in} the fine line direction of the fixed layer FP. That is, the side surface of the recording layer FF protrudes outward from the side surface of the fixed layer FP.

The storage area 20 is an area surrounded by a dotted line in the figure, and is arranged to face the fixed layer FP. The storage area 20 has, for example, the same width W _20X as the width W _{FPX in} the thin line direction of the fixed layer FP. However, the shape and size of the storage area 20 can vary depending on the material used for the recording layer FF, details of current intensity, current path, and the like. In particular, the storage area 20 may include all of the interface with the intermediate layer SP, or may include only a part of the interface with the intermediate layer SP.

The fixing layer FP is directly or indirectly connected to the electrode EL. The magnetization of the pinned layer FP is pinned in a specific direction. Examples of the magnetization pinning method include a method using a material having a sufficiently large anisotropic energy Ku for the pinned layer FP and a method of providing an antiferromagnetic layer AF between the pinned layer FP and the electrode EL. The width W _{FPX in} the thin line direction of the fixed layer FP may be the same as or different from the widths of the electrode EL and the intermediate layer SP.

As shown in FIGS. 2A and 2B, as can be seen from the fact that the width W _{FFX in} the fine line direction of the recording layer FF is larger than the width W _{FPX in} the fine line direction of the fixed layer FP, the surface area of the recording layer FF is It is larger than the surface area of the fixing layer FP. Here, the width W _{FFY in} the Y direction of the recording layer FF may be the same as the width W _{FPY in} the Y direction of the fixed layer FP (see FIG. 2A). Further, the width W _{FFY in} the Y direction of the recording layer FF _may be different from the width W _{FPY in} the Y direction of the fixed layer FP, and may be larger or smaller than the width W _{FPY in} the Y direction of the fixed layer FP ( (Refer FIG.2 (b)).

  Details of the size of each layer and the material used for each layer will be described in [1-6].

[1-2] Writing Method A data writing method (bipolar method) in the magnetic element 10 according to the present embodiment will be described with reference to FIG. Of course, the direction in which the electrons e1 and e2 flow is opposite to the direction in which the current flows.

  First, when the magnetizations of the recording layer FF and the pinned layer FP are arranged in parallel magnetization, writing is performed as follows. The electron e1 passes through the pinned layer FP from the electrode EL and a current flows in the direction toward the recording layer FF, so that the electron e1 spin-polarized in a direction parallel to the magnetization direction of the pinned layer FP becomes the intermediate layer SP and the recording layer FF. Flows into the recording layer FF through the interface. As a result, the magnetization of a partial region (storage region 20) in the vicinity of the interface with the intermediate layer SP in the recording layer FF faces a direction parallel to the magnetization of the fixed layer FP.

  On the other hand, when the magnetizations of the recording layer FF and the pinned layer FP are arranged in an antiparallel magnetization arrangement, writing is performed as follows. The electron e2 passes through the pinned layer FP from the recording layer FF and a current flows in the direction toward the electrode EL, so that the electron e2 spin-polarized in a direction antiparallel to the magnetization direction of the pinned layer FP becomes the magnetization of the recording layer FF. Act on some. As a result, the magnetization of a partial region (storage region 20) in the vicinity of the interface with the intermediate layer SP in the recording layer FF faces in a direction antiparallel to the magnetization of the fixed layer FP.

  As described above, the storage area 20 with variable magnetization exists in the recording layer FF, and the magnetization direction of the storage area 20 is in a direction corresponding to the direction in which current flows. Therefore, it is possible to write 1-bit data in one storage area 20 of the magnetic element 10 by defining the states of the parallel magnetization arrangement and the antiparallel magnetization arrangement as “1” and “0”, respectively. .

[1-3] Reading Method A data reading method in the magnetic element 10 according to the present embodiment will be described with reference to FIG.

  The electric resistance when a current is passed between the electrode EL and the recording layer FF varies depending on the relative angle between the magnetization direction of the fixed layer FP and the magnetization direction of the magnetization variable region (storage region 20) in the recording layer FF. This is a phenomenon known as a so-called tunneling magnetoresistive (TMR) effect. Data reading in the magnetic element 10 is performed by detecting the difference in resistance.

  The direction in which the current flows is the direction in which the electrons e1 pass from the electrode EL through the fixed layer FP and go to the recording layer FF. Conversely, the direction of the electrons e2 from the recording layer FF passes through the fixed layer FP and goes to the electrode EL. It can also be.

  However, when the magnitude of the current exceeds a certain threshold value, the magnetization direction of the storage area 20 changes and writing is performed. For this reason, it is possible to prevent reading and writing from being performed simultaneously by setting the magnitude of the reading current to a value smaller than this threshold value.

  When the current exceeds a certain threshold value, the position of the domain wall surrounding the storage area 20 in the recording layer FF moves in the direction in which electrons flow. For this reason, by setting the magnitude of the read current to a value smaller than this threshold value, it is possible to prevent this domain wall movement phenomenon from occurring.

  The detection of the difference in electrical resistance depending on the magnetization direction of the storage area 20 can be performed using a known circuit technique.

[1-4] Magnetization direction In the magnetic element 10 according to the present embodiment, the stable direction of the magnetization of the fixed layer FP and the magnetization of the storage region 20 in the recording layer FF is not particularly limited, and for example, in the following direction: Is set.

  3A and 3B are diagrams schematically showing the magnetization direction of the magnetic element according to the first embodiment of the present invention. For example, the magnetization of the pinned layer FP and the magnetization of the storage region 20 in the recording layer FF may be oriented in a direction parallel to the film surface (X direction) (see FIG. 3A). It may be oriented in a direction perpendicular to the surface (Z direction) (see FIG. 3B). When the magnetization is oriented perpendicularly to the film surface as shown in FIG. 3B, it is excellent in thermal stability, which is advantageous for miniaturization of the magnetic element 10.

[1-5] Modified Example of Structure The magnetic element 10 according to the present embodiment is not limited to the structure shown in FIG. 1 and can be modified to the following structure, for example.

  The fixed layer FP and the recording layer FF may have a multilayer structure including two or more ferromagnetic sublayers and zero or more nonmagnetic sublayers. That is, the fixed layer FP and the recording layer FF may be formed of a multilayer film including a plurality of ferromagnetic layers such as a ferromagnetic layer / ferromagnetic layer / ferromagnetic layer, or a ferromagnetic layer / non-magnetic layer / A structure in which two ferromagnetic layers are ferromagnetically coupled or antiferromagnetically coupled may be a multilayer film composed of ferromagnetic layers.

  As shown in FIG. 4, the intermediate layer SP is not limited to the same shape as the fixed layer FP, and may be the same thin line shape as the recording layer FF.

  As shown in FIG. 5, a constricted portion 21 may be provided around the storage area 20 of the recording layer FF. When the constricted portion 21 is provided in the thin-line-shaped recording layer FF as described above, it is difficult to cause a spatial change in the magnetization direction before and after the position of the constricted portion 21. For this reason, it is desirable to introduce such a structure because the boundary of the storage area 20 is determined. Although an example of the narrowing in the XZ plane is shown here, the present invention is not limited to the narrowed shape as illustrated, and any irregularities may be provided in the thin line-shaped recording layer FF. Further, it is possible to provide a constricted portion having the same shape as in FIG. 5 as a constriction in the XY plane.

[1-6] Material and Film Thickness of Each Layer The constituent material of each layer of the magnetic element 10 according to this embodiment will be described.

(A) Magnetic layer As the conductive magnetic material used for the recording layer FF, Co, Fe, Ni, or an alloy containing these can be used. In addition, the thickness of the recording layer FF is preferably in the range of 0.2 nm to 50 nm because the ferromagnetism is maintained and the magnetization can be changed.

  Co, Fe, Ni, or an alloy containing these can be used for the fixed layer FP. The thickness of the pinned layer FP is preferably in the range of 0.6 nm to 100 nm in order to maintain ferromagnetism and not increase the manufacturing cost. In order to stably fix the magnetization of the fixed layer FP, the fixed layer FP is preferably thicker than the recording layer FF.

  It is preferable that the material of the pinned layer FP has a higher spin polarizability because the magnetization reversal efficiency when a current is allowed to flow vertically between the pinned layer FP and the recording layer FF increases, and the write current can be reduced. At this time, there is also an advantage that MR (Magneto Resistive) ratio is increased and reading is facilitated. Therefore, a high spin polarizability material called half metal is ideal as a material for the pinned layer FP. Examples of half metals include Heusler alloys, rutile oxides, spinel oxides, perovskite oxides, double perovskite oxides, zinc blende chromium compounds, pyrite manganese compounds, and sendust alloys.

  Magnetic materials used for the pinned layer FP and the recording layer FF include Ag, Cu, Au, Al, Mg, Si, Bi, Ta, B, C, O, N, Pd, Pt, Zr, Ir, W, and Mo. , Nb, H, and other nonmagnetic elements can be added to adjust the magnetic properties and to adjust various physical properties such as crystallinity, mechanical properties, and chemical properties.

  When at least one of the fixed layer FP and the recording layer FF has a multilayer film structure, Cu, Au, Ag, Ru, Ir, Os, or any of these can be used as a material for the nonmagnetic sublayer constituting the multilayer film structure. Or an alloy containing one or more of them can be used.

When the antiferromagnetic layer AF is used to fix the magnetization of the pinned layer FP, the material of the antiferromagnetic layer AF is Fe-Mn, Pt-Mn, Pt-Cr-Mn, Ni-Mn, Pd. It is desirable to use —Mn, Pd—Pt—Mn, Ir—Mn, Pt—Ir—Mn, NiO, Fe ₂ O ₃ , a magnetic semiconductor, or the like.

  When the magnetization directions of the pinned layer FP and the recording layer FF are oriented perpendicular to the film surface (FIG. 3B), the magnetic anisotropy energy density Ku is large, and FePt, CoPt exhibiting perpendicular magnetic anisotropy. It is desirable to use FePd, CoPd, or the like. In addition, a magnetic material having a crystal structure of hcp structure (close-packed hexagonal structure) and showing perpendicular magnetic anisotropy can be used. As such a magnetic material, a material containing a metal containing Co as a main component is typical, but other metals having an hcp structure can also be used. In addition, a material exhibiting perpendicular magnetic anisotropy that is an alloy of a rare earth element and an iron group transition element can also be used. Specific examples include GdFe, GdFeCo, TbFe, TbFeCo, DyFe, DyFeCo, and the like.

(B) Nonmagnetic layer The intermediate layer SP is made of a nonconductive material. That is, it is desirable to use an insulator or a semiconductor as the material of the intermediate layer SP.

When an insulator is used as the material of the intermediate layer SP, for example, Al ₂ O ₃ (aluminum oxide), SiO ₂ (silicon oxide), MgO (magnesium oxide), AlN (aluminum nitride), Bi ₂ O ₃ (bismuth oxide) ), MgF ₂ (magnesium fluoride), CaF ₂ (calcium fluoride), SrTiO ₂ (titanium oxide / strontium), AlLaO ₃ (lanthanum oxide / aluminum oxide), Al—N—O (aluminum oxynitride), Si—N -O or the like can be used.

When a semiconductor is used as the material of the intermediate layer SP, for example, ZnO, InMn, GaN, GaAs, TiO ₂ , Zn, Te, or those doped with a transition metal can be used.

  The above-described compound material of the intermediate layer SP made of an insulator or a semiconductor does not need to have a completely accurate composition in terms of stoichiometry, and there is a deficiency or excess or deficiency of oxygen, nitrogen, fluorine, or the like. Also good.

  The thickness of the intermediate layer SP made of an insulator or a semiconductor is preferably in the range of not less than 0.2 nm and not more than 5 nm in order to allow a sufficiently large tunnel current to flow while maintaining the tunnel barrier.

[1-7] Example As an example of the present embodiment, a magnetic recording element having the following structure and material in which an antiferromagnetic layer AF was added to the structure of FIG. 1 was manufactured.

Upper electrode EL1 (Cu) / antiferromagnetic layer AF (PtMn: 15 nm) / fixed layer FP (CoFe: 12 nm) / intermediate layer SP (MgO: 0.8 nm) / recording layer FF (FeNi: 3 nm)
First, a base layer is formed above the wafer. Next, an SiO ₂ film is formed using an ultrahigh vacuum sputtering apparatus. Then, an EB (Electron Beam) resist is applied on the SiO ₂ film and EB exposure is performed. Thereby, a mask corresponding to the thin line shape of the recording layer FF is formed. Next, the SiO ₂ film in the region not covered with the mask is etched by ion etching. As a result, a fine line groove for forming the recording layer FF is formed. The thin line width of the recording layer FF is 50 nm. After etching, the mask is peeled off. Next, the recording layer FF is formed by filling the fine wire groove with FeNi using an ultra-high vacuum sputtering apparatus. Thereafter, the FeNi surface is smoothed by ion milling. Next, using an ultra-high vacuum sputtering apparatus, a laminated structure including the intermediate layer SP, the fixed layer FP, and the antiferromagnetic layer AF is formed on the recording layer FF, and a protective film is further formed on the laminated structure. It is formed. When forming each layer, a target made of a material constituting the layer was used. For this film, the intermediate layer SP, the fixed layer FP, and the antiferromagnetic layer AF are processed into a dot shape of 100 nm × 50 nm using EB in the same manner as above. Further, a SiO ₂ film is formed in the gap between the intermediate layer SP, the fixed layer FP, and the antiferromagnetic layer AF using an ultrahigh vacuum sputtering apparatus. Thereafter, the surface of the SiO ₂ film is smoothed by ion milling, and “cueing” is performed to expose the surface of the protective film. An upper electrode EL1 is formed on the surface of the protective film. The wafer is annealed in a magnetic field in a magnetic field vacuum furnace at 270 ° C. for about 10 hours to impart unidirectional anisotropy to the magnetic layer.

  About the magnetic recording element produced by the above process, the electric current was sent between upper electrode EL1 and the recording layer FF, and the resistance value of the magnetic recording element was measured. When the current was swept in the range of −10 mA to +10 mA, the change in resistance value showed hysteresis, and the current threshold value was positive and negative, and there was one each. That is, this corresponds to the change in the magnetization direction of the magnetization variable region (storage region 20) in accordance with the direction in which the current flows.

[1-8] Effect As described above, according to the magnetic element 10 of the first embodiment of the present invention, the recording layer FF may be processed into a thin line shape. No processing is required. For this reason, it becomes easier to manufacture the magnetic element 10 with reduced variations in element characteristics as compared with such a conventional magnetic element.

[2] Second Embodiment [2-1] Structure FIGS. 6A and 6B are views schematically showing a cross-sectional structure of a magnetic element according to a second embodiment of the present invention. 6A shows an antiparallel type in which the magnetization arrangement of the magnetization direction setting region 30 and the fixed layer FP is antiparallel, and FIG. 6B shows the magnetization direction setting region 30 and the fixed layer FP. A parallel type in which the magnetization arrangement is parallel is shown. The structure of the magnetic element according to the second embodiment of the present invention will be described below.

  As shown in FIGS. 6A and 6B, the magnetic element 10 according to the second embodiment has a structure different from that of the storage area 20 of the recording layer FF in addition to the same structure as that of the first embodiment. A magnetization direction setting region 30 is provided, and a magnetization direction setting mechanism 40 that controls the magnetization direction of the magnetization direction setting region 30 is further provided. The magnetization direction setting area 30 may be separated from the storage area 20 to the extent that the magnetization direction setting area 30 does not affect the storage area 20 when the magnetization control of the magnetization direction setting area 30 is performed.

  Here, in the case of the antiparallel type in FIG. 6A, the magnetization direction of the magnetization direction setting region 30 is set by the magnetization direction setting mechanism 40 so as to be antiparallel to the magnetization direction of the pinned layer FP. ing. On the other hand, in the parallel type of FIG. 6B, the magnetization direction of the magnetization direction setting region 30 is set by the magnetization direction setting mechanism 40 so as to be parallel to the magnetization direction of the fixed layer FP.

[2-2] Example of Magnetization Direction Setting Mechanism The magnetization direction setting mechanism 40 can be, for example, the following mechanism.

(A) First Example: Magnetic Coupling Type A first example of the magnetization direction setting mechanism 40 is an example of a magnetic coupling type using interlayer exchange coupling of a magnetic material.

  FIGS. 7A and 7B are views for explaining a first example (magnetic coupling type) of the magnetization direction setting mechanism according to the second embodiment of the present invention. A magnetic coupling type magnetization direction setting mechanism will be described below.

  As shown in FIGS. 7A and 7B, in the magnetic coupling type, the magnetization direction setting mechanism 40 includes a nonmagnetic layer N, a ferromagnetic layer F, and an antiferromagnetic layer AF. Here, the ferromagnetic layer F is disposed opposite to the magnetization direction setting region 30 of the recording layer FF, and the nonmagnetic layer N is provided between the ferromagnetic layer F and the magnetization direction setting region 30. Further, an antiferromagnetic layer AF for fixing the magnetization of the ferromagnetic layer F is provided.

  In such a magnetic coupling type, the magnetization control of the magnetization direction set region 30 is performed as follows. First, the magnetization direction of the ferromagnetic layer F is fixed in the first direction (in the case of this figure, rightward in the drawing) by exchange coupling between the antiferromagnetic layer AF and the ferromagnetic layer F. Magnetization direction of the recording layer FF The magnetization direction of the set region 30 is set to be antiparallel or parallel to the first direction by exchange coupling between the ferromagnetic layer F and the recording layer FF.

  Here, in general, exchange coupling between two magnetic layers via a nonmagnetic layer has a vibration property with respect to the distance between the magnetic layers (thickness of the nonmagnetic layer) as shown in FIG.

  For example, if the thickness of the nonmagnetic layer N sandwiched between the recording layer FF and the ferromagnetic layer F is t1, the coupling constant is negative, that is, antiferromagnetic coupling is realized. Therefore, at this time, as shown in FIG. 7A, the magnetization direction of the magnetization direction set region 30 is set to a direction antiparallel to the magnetization direction of the ferromagnetic layer F. In this case, since the magnetization direction of the magnetization direction setting region 30 is antiparallel to the magnetization of the pinned layer FP, the antiparallel type shown in FIG.

  If the thickness of the nonmagnetic layer N sandwiched between the recording layer FF and the ferromagnetic layer F is t2, the coupling constant is positive, that is, ferromagnetic coupling is realized. Therefore, at this time, as shown in FIG. 7B, the magnetization direction of the magnetization direction setting region 30 is set in a direction parallel to the magnetization direction of the ferromagnetic layer F. In this case, since the magnetization direction of the magnetization direction setting region 30 is parallel to the magnetization of the pinned layer FP, the parallel type shown in FIG.

  In the magnetization direction setting mechanism 40, a multilayer film can be used to combine antiferromagnetic coupling and ferromagnetic coupling.

(B) 2nd example: Current magnetic field type The 2nd example of the magnetization direction setting mechanism 40 is an example of the current magnetic field type using the magnetic field which generate | occur | produces with an electric current.

  FIGS. 9A and 9B are views for explaining a second example (current magnetic field type) of the magnetization direction setting mechanism according to the second embodiment of the present invention. The current magnetic field type magnetization direction setting mechanism will be described below.

  As shown in FIGS. 9A and 9B, in the current magnetic field type, the magnetization direction setting mechanism 40 includes a wiring M provided so as to be insulated from the recording layer FF. The wiring M is provided in the vicinity of the magnetization direction setting region 30 so as to face the magnetization direction setting region 30.

  In such a current magnetic field type, the magnetization control of the magnetization direction set region 30 is performed as follows. First, a current I is passed through the wiring M. When a current flows through the wiring M, a magnetic field H is generated around it, and the magnetization direction of the magnetization direction setting region 30 is set by the action of the magnetic field H.

  Here, the magnetization direction of the magnetization direction setting region 30 is determined according to the direction of the current I flowing through the wiring M. For example, as shown in FIGS. 9A and 9B, when the wiring M is arranged above the magnetization direction set region 30, the following is performed.

  As shown in FIG. 9A, when a current I is passed in the direction from the front to the back of the paper, a magnetic field H is generated clockwise, and the magnetization direction of the magnetization direction setting region 30 is set to the left of the paper. The In this case, since the magnetization direction of the magnetization direction setting region 30 is antiparallel to the magnetization of the pinned layer FP, the antiparallel type shown in FIG.

  As shown in FIG. 9B, when a current I is passed in the direction from the back to the front of the paper, a magnetic field H is generated counterclockwise, and the magnetization direction of the magnetization direction setting region 30 is set to the right of the paper. Is done. In this case, since the magnetization direction of the magnetization direction setting region 30 is parallel to the magnetization of the pinned layer FP, the parallel type shown in FIG.

  In order to efficiently concentrate the magnetic field H generated by the current I in the magnetization direction setting region 30, a yoke structure in which a portion other than the surface facing the magnetization direction setting region 30 of the wiring M is surrounded by a yoke layer is employed. May be. The yoke layer is made of, for example, an insulating or conductive magnetic layer. As a material of the insulating magnetic layer, for example, insulating ferrite, (Fe, Co)-(B, Si, Hf, Zr, Sm, Ta, Al)-(F, O, N), etc. Examples thereof include metal-nonmetal nano granular films. Specifically, the insulating ferrite is made of, for example, at least one material of Mn—Zn—ferrite, Ni—Zn—ferrite, MnFeO, CuFeO, FeO, and NiFeO. Examples of the material for the conductive magnetic layer include a Ni—Fe alloy, a Co—Fe alloy, a Co—Fe—Ni alloy, a Co— (Zr, Hf, Nb, Ta, Ti) -based amorphous material, (Co, Fe, Ni)-(Si, B)-(P, Al, Mo, Nb, Mn) -based amorphous materials. The yoke layer is not limited to the materials described above, and can be variously changed.

  Further, the wiring M may be arranged below the magnetization direction set region 30. In this case, the relationship between the direction in which the current I flows and the magnetization direction of the magnetization direction set region 30 is opposite to that in FIGS. 9A and 9B, and the current I is applied in the direction from the front of the paper to the back. When flowing, the magnetization direction of the magnetization direction setting region 30 is set to the right side of the drawing, and when the current I is passed in the direction from the back to the front of the drawing, the magnetization direction of the magnetization direction setting region 30 is set to the left of the drawing. Is done.

(C) Third Example: Spin Transfer Type A third example of the magnetization direction setting mechanism 40 is a spin transfer type using spin injection writing in which a current flows perpendicularly to the film surface and spin-polarized electrons act on the magnetization. It is an example.

  FIGS. 10A and 10B, FIGS. 11A and 11B are views for explaining a third example (spin transfer type) of the magnetization direction setting mechanism according to the second embodiment of the present invention. The figure is shown. Hereinafter, a spin transfer type magnetization direction setting mechanism will be described.

  As shown in FIGS. 10A and 10B and FIGS. 11A and 11B, in the spin transfer type, the magnetization direction set region 30 is directly or indirectly connected to the two electrodes ELa and ELb, respectively. Has been. That is, a multilayer film having at least one ferromagnetic layer and one nonmagnetic layer is sandwiched between at least one of the two electrodes ELa and ELb and the magnetization direction setting region 30, and the magnetization direction setting region 30. A nonmagnetic layer is directly connected to. The thickness of this nonmagnetic layer is smaller than the spin diffusion length.

  Here, in the case of the single structure shown in FIGS. 10A and 10B, the magnetization direction setting mechanism 40 includes a nonmagnetic layer N, a ferromagnetic layer F, and electrodes ELa and ELb. The nonmagnetic layer N, the ferromagnetic layer F, and the electrode ELa are sequentially connected to the upper surface of the magnetization direction setting region 30 of the recording layer FF, and the electrode ELb is connected to the lower surface of the magnetization direction setting region 30.

  In the dual structure shown in FIGS. 11A and 11B, the magnetization direction setting mechanism 40 includes nonmagnetic layers N1 and N2, ferromagnetic layers F1 and F2, and electrodes ELa and ELb. Then, the nonmagnetic layer N1, the ferromagnetic layer F1, and the electrode ELa are sequentially connected to the upper surface of the magnetization direction setting region 30 of the recording layer FF, and the nonmagnetic layer N2 and the ferromagnetic layer F2 are connected to the lower surface of the magnetization direction setting region 30. The electrodes ELb are connected in order. The magnetizations of the ferromagnetic layers F1, F2 are arranged antiparallel.

  In such a spin transfer type, the magnetization control of the magnetization direction setting region 30 is performed as follows.

  First, the case of a single structure will be described with reference to FIGS.

  As shown in FIG. 10A, when the magnetization of the magnetization direction setting region 30 is arranged in an antiparallel magnetization arrangement with respect to the magnetization of the ferromagnetic layer F, writing is performed as follows. The electron e2 passes a current in a direction from the magnetization direction setting region 30 through the ferromagnetic layer F toward the electrode ELa. Thereby, the electrons e2 spin-polarized in a direction antiparallel to the magnetization direction of the ferromagnetic layer F by the spin filter effect act on the magnetization of the magnetization direction setting region 30. As a result, the magnetization of the magnetization direction setting region 30 faces in a direction antiparallel to the ferromagnetic layer F. In this case, since the magnetization direction of the magnetization direction setting region 30 is antiparallel to the magnetization of the pinned layer FP, the antiparallel type shown in FIG.

  On the other hand, as shown in FIG. 10B, when the magnetization of the magnetization direction set region 30 is arranged parallel to the magnetization of the ferromagnetic layer F, writing is performed as follows. The electrons e1 pass a current in a direction from the electrode ELa through the ferromagnetic layer F toward the magnetization direction setting region 30. Thereby, electrons e1 spin-polarized in a direction parallel to the magnetization direction of the ferromagnetic layer F by the spin filter effect flow into the magnetization direction setting region 30 through the interface between the nonmagnetic layer N and the magnetization direction setting region 30. . As a result, the magnetization of the magnetization direction setting region 30 is directed in a direction parallel to the ferromagnetic layer F. In this case, since the magnetization direction of the magnetization direction setting region 30 is parallel to the magnetization of the pinned layer FP, the parallel type shown in FIG.

  As described above, by passing a current between the two electrodes ELa and ELb, the magnetization of the magnetization direction setting region 30 passes from or reflects through the ferromagnetic layer F and is spin-polarized by a spin filter effect. It receives the spin transfer torque and turns in the direction according to the direction of the flowing current.

  Next, the case of the dual structure will be described with reference to FIGS. 11 (a) and 11 (b).

  As shown in FIG. 11A, when the magnetization of the magnetization direction setting region 30 is arranged in an antiparallel magnetization arrangement with respect to the magnetization of the ferromagnetic layer F1, writing is performed as follows. The electron e2 passes a current in a direction from the ferromagnetic layer F2 through the ferromagnetic layer F1 toward the electrode ELa. Thereby, the electrons e2 spin-polarized in a direction antiparallel to the magnetization direction of the ferromagnetic layer F1 by the spin filter effect act on the magnetization of the magnetization direction setting region 30. As a result, the magnetization of the magnetization direction setting region 30 faces in a direction antiparallel to the ferromagnetic layer F1. In this case, since the magnetization direction of the magnetization direction setting region 30 is antiparallel to the magnetization of the pinned layer FP, the antiparallel type shown in FIG.

  On the other hand, as shown in FIG. 11B, when the magnetization of the magnetization direction setting region 30 is arranged parallel to the magnetization of the ferromagnetic layer F1, writing is performed as follows. The electron e1 passes a current in a direction from the electrode ELa to the magnetization direction setting region 30 through the ferromagnetic layer F1. Thereby, electrons e1 spin-polarized in a direction parallel to the magnetization direction of the ferromagnetic layer F1 by the spin filter effect flow into the magnetization direction setting region 30 through the interface between the nonmagnetic layer N and the magnetization direction setting region 30. . Furthermore, spin-polarized electrons e 1 that have passed through the magnetization direction setting region 30 and reflected at the interface between the ferromagnetic layer F 2 and the magnetization direction setting region 30 act on the magnetization of the magnetization direction setting region 30. As a result, the magnetization of the magnetization direction setting region 30 is directed in a direction parallel to the ferromagnetic layer F. In this case, since the magnetization direction of the magnetization direction setting region 30 is parallel to the magnetization of the pinned layer FP, the parallel type shown in FIG.

  As described above, by passing a current between the two electrodes ELa and ELb, the magnetization of the magnetization direction setting region 30 passes or reflects through the ferromagnetic layers F1 and F2 and is spin-polarized by the spin filter effect. It receives the spin transfer torque from the current and turns in the direction according to the direction of the flowing current.

  Incidentally, in the dual structure, the current required for changing the magnetization direction of the magnetization direction set region 30 as compared with the single structure by fixing the magnetization directions of the ferromagnetic layers F1 and F2 to be antiparallel. There is an advantage that can be reduced to half or less.

[2-3] Writing Method With reference to FIGS. 6A and 6B, a data writing method (unipolar method) in this element will be described.

(A) Anti-Parallel Type With reference to FIG. 6A, an anti-parallel type writing method in which the magnetization direction of the magnetization direction setting region 30 is set anti-parallel to the magnetization direction of the fixed layer FP will be described. .

  First, when making the magnetization direction of the storage region 20 parallel to the magnetization direction of the pinned layer FP, the same method as in the first embodiment is used. That is, the electron e1 passes a current in a direction from the electrode EL to the recording layer FF through the fixed layer FP.

  On the other hand, when the magnetization direction of the storage region 20 is antiparallel to the magnetization direction of the pinned layer FP, a method different from that of the first embodiment is used. First, the magnetization direction of the magnetization direction setting region 30 is set to a direction antiparallel to the magnetization direction of the pinned layer FP using the magnetization direction setting mechanism 40 described above. Next, a current is passed in the thin line direction of the recording layer FF. That is, the electrons e2 are caused to flow in the direction in which the domain wall is desired to move (the right direction on the page). As a result, the domain wall position of the magnetic domain including the storage area 20 in the recording layer FF moves to the right in the drawing. As a result, the magnetization direction of the magnetization direction setting region 30 is transmitted to the magnetization of the storage region 20, and the magnetization direction of the storage region 20 becomes antiparallel to the magnetization direction of the fixed layer FP. In such a state, the current is turned off to stop the domain wall movement. Note that it is preferable that the thin recording layer FF has irregularities such as the constricted portion 21 (FIG. 5) described above, because the domain wall tends to stop at the position of the storage area 20.

(B) Parallel Type With reference to FIG. 6B, a parallel type writing method in which the magnetization direction of the magnetization direction setting region 30 is set parallel to the magnetization direction of the fixed layer FP will be described.

  First, when making the magnetization direction of the storage region 20 parallel to the magnetization direction of the pinned layer FP, a method different from that of the first embodiment is used. First, the magnetization direction of the magnetization direction setting region 30 is set to a direction parallel to the magnetization direction of the pinned layer FP using the magnetization direction setting mechanism 40 described above. Next, a current is passed in the thin line direction of the recording layer FF. That is, the electrons e1 are caused to flow in the direction in which the domain wall is desired to move (the right direction on the page). As a result, the domain wall position of the magnetic domain including the storage area 20 in the recording layer FF moves to the right in the drawing. As a result, the magnetization direction of the magnetization direction setting region 30 is transmitted to the magnetization of the storage region 20, and the magnetization direction of the storage region 20 becomes parallel to the magnetization direction of the fixed layer FP. In such a state, the current is turned off to stop the domain wall movement. Note that it is preferable that the thin recording layer FF has irregularities such as the constricted portion 21 (FIG. 5) described above, because the domain wall tends to stop at the position of the storage area 20.

  On the other hand, when the magnetization direction of the storage region 20 is antiparallel to the magnetization direction of the pinned layer FP, the same method as in the first embodiment is used. That is, the electron e2 passes a current from the recording layer FF to the electrode EL through the fixed layer FP.

[2-4] Reading Method The data reading method in the second embodiment is performed in the same manner as in the first embodiment.

[2-5] Effects As described above, according to the magnetic element 10 of the second embodiment of the present invention, the same effects as those of the first embodiment can be obtained. Furthermore, in the case of the second embodiment, the magnetization direction setting region 30 is provided in the recording layer FF, and the magnetization direction is controlled by the domain wall movement. For this reason, the current flowing between the recording layer FF and the fixed layer FP can be made only in one direction, so that a diode having a smaller area than the transistor can be used as a selective switching element for flowing this current.

  Also in the second embodiment, the contents such as [1-4] magnetization direction, [1-5] structure modification described in the first embodiment, [1-6] material and film thickness of each layer, etc. It is possible to apply

[3] Third Embodiment By arranging a large number of the above-described magnetic elements 10 and selecting a specific magnetic element 10 so that writing and reading operations can be performed, a magnetic recording apparatus can be obtained. is there. Here, an embodiment of the magnetic recording apparatus will be described.

[3-1] Example 3-1
Example 3-1 is an example of a magnetic recording apparatus using the magnetic element 10 according to the first embodiment described above.

  12A and 12B are views schematically showing the structure of Example 3-1 of the magnetic recording apparatus according to the third embodiment of the present invention. Hereinafter, Example 3-1 will be described.

  As shown in FIGS. 12A and 12B, the magnetic recording apparatus 100 has a laminated structure of an intermediate layer SP-n, a fixed layer FP-n, and an electrode EL-n on one thin-line-shaped recording layer FF. A plurality of magnetic elements 10-n share one recording layer FF (n = 1, 2, 3,...). In the recording layer FF, a storage area 20-n is provided in an area near the interface in contact with each intermediate layer SP-n. The intermediate layer SP may be separated for each magnetic element 10-n (FIG. 12A), or may be shared by a plurality of magnetic elements 10-n (FIG. 12B).

  The writing and reading methods of the magnetic recording apparatus 100 according to Example 3-1 are based on the method described in the section of the first embodiment.

  In the writing method, a selection transistor (not shown) is connected to the electrode EL-n, and a current is passed between the electrode EL-n selected by the transistor and the recording layer FF-n. It is possible to selectively write only the storage area 20-n in contact with −n through the fixed layer FP-n and the intermediate layer SP-n.

  Similarly, the reading method is performed by passing a current between the selected electrode EL-n and the recording layer FF-n. As described in the section of the first embodiment, the stored data is read out as a difference in electric resistance value. The largest contribution to the electric resistance value is the electric power of the intermediate layer SP-n. Resistance. Therefore, it is possible to detect only desired bit data without being affected by the details of the magnetic structure in the recording layer FF-n.

  However, in the case of a structure in which the intermediate layer SP is not separated as shown in FIG. 12B, the storage area (20-1) to be recorded and reproduced and the corresponding electrode (EL-1). Must be larger than the current flowing between another adjacent storage area (referred to as 20-2) and the electrode EL-1. For this reason, the film thickness of the intermediate layer SP-n needs to be thinner than the interval between the adjacent fixed layers FP-n, and is desirably set to 1/10 or less.

  As described above, in Example 3-1, since the magnetization direction of each storage area 20-n can be controlled and held independently, 1-bit data is recorded and stored in each storage area 20-n. it can. Therefore, when n sets of intermediate layers SP, fixed layers FP, and electrodes EL are connected to one thin-line-shaped recording layer FF, n storage areas 20 exist in the recording layer FF, and n bits of It can be used as a magnetic recording apparatus 100 that stores data.

[3-2] Example 3-2
Example 3-2 is an example of a magnetic recording apparatus using the magnetic element 10 according to the second embodiment described above.

  FIGS. 13A and 13B are views schematically showing the structure of Example 3-2 of the magnetic recording apparatus according to the third embodiment of the present invention. Hereinafter, Example 3-2 will be described.

  As shown in FIGS. 13A and 13B, in Example 3-2, in addition to the structure of Example 3-1, the magnetization direction setting mechanism 40 and the magnetization direction setting are the same as those in the second embodiment. Region 30 is provided. The intermediate layer SP may be separated for each magnetic element 10-n (FIG. 13A), or may be shared by a plurality of magnetic elements 10-n (FIG. 13B).

  The writing and reading methods of the magnetic recording apparatus 100 according to Example 3-2 are based on the method described in the section of the second embodiment.

  As a typical example of the writing method of this apparatus, there is a method in which data is overwritten first and then data is written. Batch overwriting of the first stage data is performed by setting the magnetization direction of the magnetization direction set region 30 using the magnetization direction setting mechanism 40, and moving the domain wall position by passing a current in the thin line direction of the recording layer FF. This is done by setting the magnetization direction of all the storage areas 20-n to the same direction as the magnetization direction of the magnetization direction setting area 30. In the second stage of data writing, the storage region 20-n to be changed in the magnetization direction antiparallel to the magnetization direction of the magnetization direction setting region 30 is selected, and the corresponding electrode EL-n is selected. This is performed by selecting a transistor (not shown) and passing a current between the electrode EL-n and the recording layer FF-n.

  As for the reading method, as in the magnetic recording device 100 having the structure of FIGS. 12A and 12B, a current is passed between the selected electrode EL-n and the recording layer FF-n. Is called.

[3-3] Effect As described above, according to the third embodiment of the present invention, it is easy to manufacture the magnetic element 10 with reduced variations in element characteristics, and integration is performed using the magnetic element 10. And a magnetic storage device 100 that achieves both stable operation and stable operation.

[4] Fourth Embodiment By arranging a plurality of magnetic recording devices 100 of the third embodiment and sharing a part thereof, a highly integrated magnetic random access memory (MRAM) can be obtained. Such a magnetic recording apparatus can be configured. Hereinafter, this embodiment will be described with reference to examples.

[4-1] Example 4-1
FIG. 14 is a diagram schematically showing the structure of Example 4-1 of the magnetic recording apparatus according to the fourth embodiment of the present invention. Hereinafter, Example 4-1 will be described.

  In Example 4-1, the magnetic recording device 100 [1], 100 [2],..., 100 [m] (m ≧ 1) of the third embodiment is used. In this example, the recording layers FF [i] included in each magnetic recording device 100 [i] (1 ≦ i ≦ m) are arranged so that the thin line directions are parallel to each other. In addition, as the magnetic recording apparatus 100 of the third embodiment, any structure described in the section of the third embodiment can be used.

  Each magnetic recording device 100 [i] (i = 1,..., M) includes n pinned layers FP separated from each other, and is j (j = 1,..., N) th from the end. Each of the fixed layers FP is referred to as FP [i, j]. The electrode connected to the fixed layer FP [i, j] is EL [i, j], and the intermediate layer connected to the fixed layer FP [i, j] is SP [i, j] (if not separated) SP [i]).

  When the magnetic recording device 100 [i] has a structure in which the intermediate layer SP is separated as shown in FIGS. 12A and 13A, the electrode EL [i, j] and the electrode FP [i, j] The set of intermediate layers SP [i, j] is hereinafter referred to as a magnetic element R [i, j], and the recording layer FF [i] is hereinafter referred to as a wiring WL [i]. On the other hand, when the magnetic recording device 100 [i] has a structure in which the intermediate layer SP is not separated as shown in FIGS. 12B and 13B, the electrode EL [i, j] and the electrode FP [i, j] is called a magnetic element R [i, j], and a set of the recording layer FF [i] and the intermediate layer SP [i] is hereinafter called a wiring WL [i].

  Magnetic elements R [i, j] belonging to different i and same j are connected to a common wiring BL [j] via a selection transistor Tr [i, j]. In the selection transistor Tr [i, j], one end of the current path is connected to the magnetic element R [i, j], the other end of the current path is connected to the ground terminal or the power supply terminal, and the gate is connected to the wiring BL [j]. It is connected. In addition, a peripheral circuit S such as a decoder and a read circuit for selecting each wiring is connected to each wiring outside the memory cell array MCA. These can be configured using known techniques.

  At the time of writing, first, the selection transistor Tr is turned on by selecting a wiring BL having an address corresponding to an address signal from the outside. Next, recording is performed by causing a current Iw to flow through the wiring WL connected to the magnetic element R.

  At the time of reading, as with recording, the wiring WL and the wiring BL are selected one by one and the current Is is passed between them. The current value Is must be smaller than Iw. Other restrictions are as described in the above embodiments.

[4-2] Example 4-2
The selection transistor Tr in Example 4-1 described above can be omitted. Such an embodiment has an advantage that storage elements can be integrated at high density because it is not necessary to ensure the area of the transistor Tr. However, there may be a problem that the S / N ratio is impaired by a current (so-called sneak current) passing through the storage area 20 other than the storage area 20 to be recorded and reproduced.

  Therefore, in Example 4-2, for example, a diode D is used as a small-area switching element instead of the selection transistor Tr. The diode D has a simple structure compared to the transistor Tr and requires a small area, which is advantageous for high integration.

  FIG. 15 is a diagram schematically showing the structure of Example 4-2 of the magnetic recording apparatus according to the fourth embodiment of the invention. Hereinafter, Example 4-2 will be described.

  In Example 4-2, all the magnetic recording apparatuses 100 described in the third embodiment can be used. When the magnetic recording device 100 shown in FIGS. 13A and 13B is used, the direction in which current flows between the electrode EL and the recording layer FF is a predetermined direction. What is necessary is just to comprise so that it may correspond with the forward direction of the diode D. FIG. At this time, the sneak current is suppressed by the rectifying action of the diode D, and as a result, both high integration and securing of the SN ratio are compatible.

[4-3] Effects As described above, according to the fourth embodiment of the present invention, the same effects as those of the third embodiment can be obtained. The fourth embodiment is an embodiment suitable for high integration.

[5] Others Embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, regarding the specific dimensional relationship and materials of each element constituting the magnetic element, and other shapes and materials such as electrodes, passivation, and insulation structure, those skilled in the art can appropriately select the present invention by appropriately selecting from a known range. As long as the same effect can be obtained, it is included in the scope of the present invention.

  In the magnetic element of the present invention, the structure shown in each section of each embodiment can be turned upside down.

  In addition, each component of the magnetic element such as an antiferromagnetic layer, an intermediate layer, and an insulating layer may be formed as a single layer, or may have a structure in which two or more layers are stacked.

  In addition, all magnetic elements and magnetic recording devices that can be implemented by those skilled in the art based on the magnetic elements and magnetic recording devices described above as embodiments of the present invention also include the gist of the present invention. As long as it belongs to the scope of the present invention.

  In addition, in the category of the idea of the present invention, those skilled in the art can conceive various changes and modifications, and it is understood that these changes and modifications also belong to the scope of the present invention. .

The figure which shows typically the cross-section of the magnetic element which concerns on the 1st Embodiment of this invention. The planar structure of the magnetic element according to a first embodiment of the present invention is a diagram schematically showing, FIG. 2 (a) illustrates a case width W _FFY recording layer is equal to the width W _FPY pinned layer, FIG. FIG. 2B is a diagram when the width W _FFY of the recording layer is larger than the width W _FPY of the fixed layer. 3A and 3B are diagrams schematically showing the magnetization direction of the magnetic element according to the first embodiment of the present invention, in which FIG. 3A is a diagram of a parallel magnetization type, and FIG. 3B is a diagram of a perpendicular magnetization type. The figure which shows typically the cross-section of the modification of the magnetic element which concerns on the 1st Embodiment of this invention. The figure which shows typically the cross-section of the modification of the magnetic element which concerns on the 1st Embodiment of this invention. It is a figure which shows typically the cross-section of the magnetic element which concerns on the 2nd Embodiment of this invention, Fig.6 (a) is a figure of an antiparallel type, FIG.6 (b) is a figure of a parallel type. It is a figure for demonstrating the 1st example (magnetic coupling type) of the magnetization direction setting mechanism based on the 2nd Embodiment of this invention, Fig.7 (a) is an antiparallel type figure, FIG.7 (b) ) Is a parallel figure. The figure which shows the relationship between the thickness of a nonmagnetic layer, and the coupling force between two ferromagnetic layers which pinch | interpose this nonmagnetic layer in the 1st example of the magnetization direction setting mechanism which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the 2nd example (current magnetic field type) of the magnetization direction setting mechanism which concerns on the 2nd Embodiment of this invention, Fig.9 (a) is an antiparallel type figure and FIG.9 (b). Is a parallel figure. It is a figure for demonstrating the 3rd example (spin transfer type: single structure) of the magnetization direction setting mechanism based on the 2nd Embodiment of this invention, Fig.10 (a) is an antiparallel type figure, FIG. (B) is a parallel view. It is a figure for demonstrating the 3rd example (spin transfer type: dual structure) of the magnetization direction setting mechanism based on the 2nd Embodiment of this invention, Fig.11 (a) is an antiparallel type figure, FIG.11. (B) is a parallel view. FIGS. 12A and 12B are diagrams schematically showing the structure of Example 3-1 of the magnetic recording apparatus according to the third embodiment of the present invention, FIG. 12A is a non-magnetic layer separation type, and FIG. The nonmagnetic layer sharing type figure. FIGS. 13A and 13B are diagrams schematically showing a structure of Example 3-2 of the magnetic recording apparatus according to the third embodiment of the present invention, FIG. 13A is a non-magnetic layer separation type, and FIG. The nonmagnetic layer sharing type figure. The figure which shows typically the structure of Example 4-1 of the magnetic-recording apparatus which concerns on the 4th Embodiment of this invention. The figure which shows typically the structure of Example 4-2 of the magnetic-recording apparatus which concerns on the 4th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10, R ... Magnetic element, 20 ... Memory area, 21 ... Constriction part, 30 ... Magnetization direction set area, 40 ... Magnetization direction setting mechanism, FF ... Recording layer, SP ... Intermediate layer, FP ... Fixed layer, EL ... Electrode , N ... nonmagnetic layer, F ... ferromagnetic layer, AF ... antiferromagnetic layer, M ... wiring, I ... current, H ... magnetic field, Tr ... transistor, D ... diode, WL ... word line, BL ... bit line, S: Peripheral circuit.

Claims (15)

A first magnetic layer having a fixed magnetization direction;
The first magnetic layer includes a first region having a variable magnetization direction disposed opposite to the first magnetic layer, has a width larger than that of the first magnetic layer in a direction parallel to the film surface, and is electrically conductive. A second magnetic layer formed of a material;
A magnetic element comprising: a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer and formed of a nonconductive material. By flowing a first current from the first magnetic layer to the second magnetic layer and directing the magnetization of the first region in a first direction, the magnetization of the first magnetic layer and the first magnetic layer The magnetization of one region to the first magnetization arrangement,
By passing a second current from the second magnetic layer to the first magnetic layer and directing the magnetization of the first region in a second direction, the magnetization of the first magnetic layer and the first magnetic layer The magnetic element according to claim 1, wherein the magnetization of the first region is set to the second magnetization arrangement. The second magnetic layer further includes a second region,
When the magnetization of the first magnetic layer and the magnetization of the first region are set to the first magnetization arrangement, a first current is passed between the first magnetic layer and the second magnetic layer. , Setting the magnetization of the first region in the first magnetization arrangement in a first direction,
When the magnetization of the first magnetic layer and the magnetization of the first region are set to the second magnetization arrangement, the magnetization direction of the second region is set, and the film of the second magnetic layer By passing a second current in a direction parallel to the surface, the domain wall of the magnetic domain including the first region is moved in the second magnetic layer, and the magnetization of the first region is changed to the first region. 2. The magnetic element according to claim 1, wherein the second magnetization arrangement is set in a direction according to the magnetization direction of the second region.   When the magnetization direction of the first magnetic layer and the magnetization direction of the second region are antiparallel, the first magnetization configuration is a parallel magnetization configuration, and the second magnetization configuration is The magnetic element according to claim 1, wherein the magnetic element has an antiparallel magnetization arrangement.   When the magnetization direction of the first magnetic layer and the magnetization direction of the second region are parallel, the first magnetization arrangement is an antiparallel magnetization arrangement, and the second magnetization arrangement is The magnetic element according to claim 1, wherein the magnetic element has a parallel magnetization arrangement. A third magnetic layer disposed opposite to the second region;
A second nonmagnetic layer disposed between the third magnetic layer and the second region;
The magnetization direction of the second region is set by exchange coupling between the second magnetic layer and the third magnetic layer according to the film thickness of the second nonmagnetic layer. The magnetic element according to claim 1. A wiring further disposed opposite to the second region and insulated from the second magnetic layer;
2. The magnetic field generated by a current flowing through the wiring is applied to the magnetization of the second region, and the magnetization of the second region is set according to a direction in which the current flows. The magnetic element according to 1. A third magnetic layer disposed opposite to the second region;
A second nonmagnetic layer disposed between the third magnetic layer and the second region;
2. A current is passed between the second magnetic layer and the third magnetic layer, and the magnetization of the second region is set according to a direction in which the current flows. The magnetic element described. A third magnetic layer disposed opposite to the first surface of the second region;
A second nonmagnetic layer disposed between the third magnetic layer and the first surface of the second region;
A fourth magnetic layer disposed opposite to the second surface of the second region;
A third nonmagnetic layer disposed between the fourth magnetic layer and the second surface of the second region;
The magnetization direction of the third magnetic layer and the magnetization direction of the fourth magnetic layer are antiparallel,
2. A current is passed between the third magnetic layer and the fourth magnetic layer, and the magnetization of the second region is set according to a direction in which the current flows. The magnetic element described.   The magnetic element according to claim 1, wherein a side surface of the second magnetic layer protrudes from a side surface of the first magnetic layer.   2. The magnetic element according to claim 1, wherein the magnetizations of the first and second magnetic layers are oriented in a direction parallel to the film surface.   The magnetic element according to claim 1, wherein the magnetizations of the first and second magnetic layers are oriented in a direction perpendicular to the film surface.   The width in the direction parallel to the film surface of the first nonmagnetic layer is the same as the width in the direction parallel to the film surface of the second magnetic layer. The magnetic element described.   A magnetic recording apparatus comprising the magnetic element according to claim 1. A first magnetic layer having a fixed magnetization direction;
A width that is greater than the first magnetic layer in a direction parallel to the film surface, including a first region and a second region that are arranged opposite to the first magnetic layer and have a variable magnetization direction. A second magnetic layer formed of a conductive material,
A first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer and formed of a nonconductive material;
When the magnetization of the first magnetic layer and the magnetization of the first region are set to the first magnetization arrangement, a first current is passed between the first magnetic layer and the second magnetic layer. And setting the magnetization of the first region to the first magnetization arrangement in a direction according to a first direction,
Setting the magnetization direction of the second region when the magnetization of the first magnetic layer and the magnetization of the first region are in a second magnetization arrangement; and the second magnetic layer By causing a second current to flow in a direction parallel to the film surface, the domain wall of the magnetic domain including the first region is moved in the second magnetic layer, and the magnetization of the first region is changed. And a step of setting the second magnetization arrangement in a direction corresponding to the direction of the magnetization of the second region.

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