Magnetoresistance effect element, magnetic array and magnetization rotation element

Abstract

To provide a magnetoresistance effect element, a magnetic array and a magnetization rotational element, which have low power consumption.SOLUTION: A magnetoresistance effect element includes: a laminate including a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer; wiring connected to a first ferromagnetic layer side of the laminate; and a spacer layer partially sandwiched between the laminate and the wiring. A first surface of the first ferromagnetic layer on a wiring side has an overlapping surface overlapping with the spacer layer when viewed from the lamination direction of the laminate, and a non-overlapping surface not overlapping with the spacer layer when viewed from the lamination direction. The overlapping surface and the non-overlapping surface have different heights in the lamination direction.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a magnetoresistive element, a magnetic array, and a magnetization rotation element. [Background technology]

[0002] Giant magnetoresistance (GMR) elements, which are made up of a multilayer film of ferromagnetic layers and nonmagnetic layers, and tunnel magnetoresistance (TMR) elements, which use an insulating layer (tunnel barrier layer, barrier layer) as the nonmagnetic layer, are known as magnetoresistance effect elements. Magnetoresistance effect elements can be applied to magnetic sensors, high-frequency components, magnetic heads, and nonvolatile random access memories (MRAM).

[0003] MRAM is a memory element in which magnetoresistive elements are integrated. MRAM reads and writes data by utilizing the property that the resistance of a magnetoresistive element changes when the magnetization directions of two ferromagnetic layers sandwiching a nonmagnetic layer in the magnetoresistive element change. The magnetization direction of the ferromagnetic layer is controlled, for example, by using a magnetic field generated by an electric current. In addition, the magnetization direction of the ferromagnetic layer is controlled, for example, by using spin transfer torque (STT) generated by passing a current in the stacking direction of the magnetoresistive element.

[0004] When using STT to rewrite the magnetization direction of the ferromagnetic layer, a current is passed in the stacking direction of the magnetoresistive element, and the write current causes deterioration of the characteristics of the magnetoresistive element.

[0005] In recent years, attention has been focused on methods that do not require current to flow in the stacking direction of a magnetoresistive element during writing. One such method is a writing method that utilizes spin-orbit torque (SOT) (for example, Patent Document 1). SOT is induced by spin current generated by spin-orbit interaction or the Rashba effect at the interface of different materials. The current for inducing SOT in a magnetoresistive element flows in a direction that intersects with the stacking direction of the magnetoresistive element. In other words, there is no need to flow current in the stacking direction of the magnetoresistive element, and this is expected to extend the life of the magnetoresistive element. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2017-216286 A Summary of the Invention [Problem to be solved by the invention]

[0007] A magnetic array has a plurality of integrated magnetoresistance effect elements. When the reversal current density of each magnetoresistance effect element increases, the power consumption of the magnetic array increases. The reversal current density is the current density required to reverse the magnetization of the magnetoresistance effect element, and the magnetoresistance effect element operates by reversing the magnetization. There is a demand to reduce the reversal current density of the magnetoresistance effect element and suppress the power consumption of the magnetic array.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a magnetoresistive element, a magnetic array, and a magnetization rotation element with low power consumption. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides the following means.

[0010] (1) A magnetoresistive effect element according to a first aspect comprises a laminate including a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wiring connected to the first ferromagnetic layer side of the laminate, and a spacer layer partially sandwiched between the laminate and the wiring, wherein a first surface of the first ferromagnetic layer on the wiring side has an overlapping surface that overlaps with the spacer layer when viewed from the stacking direction of the laminate, and a non-overlapping surface that does not overlap with the spacer layer when viewed from the stacking direction, and the overlapping surface and the non-overlapping surface have different heights in the stacking direction.

[0011] (2) In the magnetoresistive element according to the above aspect, the spacer layer may have an opening, and the laminate may cover the opening.

[0012] (3) In a cross section of the magnetoresistive element according to the above aspect taken along a first direction in which the wiring extends and along the stacking direction, the overlapping surface may have a first overlapping region and a second overlapping region, the first overlapping region and the second overlapping region being located on either side of a midpoint of the stack in the first direction.

[0013] (4) In the magnetoresistive element according to the above aspect, the nonmagnetic layer has a first portion overlapping with the spacer layer as viewed in the stacking direction and a second portion not overlapping with the spacer layer as viewed in the stacking direction, and the first portion and the second portion may have different heights in the stacking direction.

[0014] (5) In the magnetoresistive element according to the above aspect, the nonmagnetic layer has a first portion overlapping the spacer layer when viewed from the stacking direction, and a second portion not overlapping the spacer layer when viewed from the stacking direction, and the nonmagnetic layer may be curved such that the second portion is closer to the wiring than the first portion.

[0015] (6) The magnetoresistive element according to the above aspect may further include an insulating layer covering a side surface of the laminate and the wiring, and the spacer layer may be located between the insulating layer and the wiring.

[0016] (7) In the magnetoresistive element according to the above aspect, an area of ​​the overlapping surface may be larger than an area of ​​the non-overlapping surface.

[0017] (8) In the magnetoresistive element according to the above aspect, an area of ​​the non-overlapping surface may be larger than an area of ​​the overlapping surface.

[0018] (9) In the magnetoresistive element according to the above aspect, the thickness of the portion of the spacer layer that contacts the stack may be greater than the spin diffusion length of the spacer layer.

[0019] (10) In the magnetoresistive element according to the above aspect, the thickness of the spacer layer at the portion in contact with the stack may be smaller than the spin diffusion length of the spacer layer.

[0020] (11) In the magnetoresistive element according to the above aspect, the thickness of the portion of the spacer layer in contact with the stack may be thinner than the thickness of the portion of the spacer layer not in contact with the stack.

[0021] (12) In the magnetoresistive element according to the above aspect, the spacer layer may be made of a metal.

[0022] (13) In the magnetoresistive element according to the above aspect, the spacer layer may be an oxide, a nitride, or an oxynitride.

[0023] (14) A magnetic array according to a second aspect includes a plurality of magnetoresistance effect elements according to the above aspect.

[0024] (15) A magnetization rotation element according to a third aspect comprises a first ferromagnetic layer, a wiring connected to the first ferromagnetic layer, and a spacer layer partially sandwiched between the first ferromagnetic layer and the wiring, wherein a first surface of the first ferromagnetic layer on the wiring side has an overlapping surface that overlaps with the spacer layer when viewed from a stacking direction of the first ferromagnetic layer, and a non-overlapping surface that does not overlap with the spacer layer when viewed from the stacking direction, and the overlapping surface and the non-overlapping surface have different heights in the stacking direction. Effect of the Invention

[0025] The magnetoresistive element, the magnetic array and the magnetization rotating element according to the present invention consume low power. [Brief description of the drawings]

[0026] [Figure 1] FIG. 2 is a circuit diagram of the magnetic array according to the first embodiment. [Diagram 2]3 is a cross-sectional view of a characteristic portion of the magnetic array according to the first embodiment. FIG. [Diagram 3] 1 is a cross-sectional view of a magnetoresistive effect element according to a first embodiment. [Figure 4] FIG. 1 is a plan view of a magnetoresistive effect element according to a first embodiment. [Diagram 5] FIG. 11 is a plan view of a magnetoresistive effect element according to a first modified example. [Figure 6] FIG. 11 is a cross-sectional view of a magnetoresistive effect element according to a second embodiment. [Figure 7] FIG. 11 is a cross-sectional view of a magnetoresistive effect element according to a third embodiment. [Figure 8] FIG. 11 is a cross-sectional view of a magnetoresistive effect element according to a fourth embodiment. [Figure 9] FIG. 13 is a plan view of a magnetoresistive effect element according to a fourth embodiment. [Figure 10] FIG. 13 is a plan view of a magnetoresistive effect element according to a fifth embodiment. [Figure 11] FIG. 13 is a cross-sectional view of a magnetization rotating element according to a sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The present embodiment will be described in detail below with reference to the drawings as appropriate. The drawings used in the following description may show characteristic parts in an enlarged scale for the sake of convenience in order to make the characteristics easier to understand, and the dimensional ratios of each component may differ from the actual ones. The materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited thereto. They may be modified as appropriate within the scope of the effects of the present invention.

[0028] First, the directions are defined. One direction on one surface of the substrate Sub (see FIG. 2) described later is defined as the x direction, and the direction perpendicular to the x direction is defined as the y direction. The x direction is, for example, the direction from the first conductive layer 41 to the second conductive layer 42. The x direction is an example of a first direction. The z direction is a direction perpendicular to the x direction and the y direction. The z direction is an example of a stacking direction. Hereinafter, the +z direction may be expressed as "up" and the -z direction as "down". Up and down do not necessarily coincide with the direction in which gravity is applied.

[0029] In this specification, "extending in the x-direction" means, for example, that the dimension in the x-direction is greater than the smallest dimension among the dimensions in the x-direction, y-direction, and z-direction. The same applies to extending in other directions. In this specification, "connection" is not limited to physical connection. For example, "connection" is not limited to two layers being physically in contact with each other, but also includes a case where two layers are connected with another layer sandwiched between them. In addition, "connection" also includes a case where two components are electrically connected, or a case where they are connected via a switching element or the like.

[0030] "First embodiment" 1 is a configuration diagram of a magnetic array 200 according to a first embodiment. The magnetic array 200 includes a plurality of magnetoresistance effect elements 100, a plurality of write wirings WL, a plurality of common wirings CL, a plurality of read wirings RL, a plurality of first switching elements Sw1, a plurality of second switching elements Sw2, and a plurality of third switching elements Sw3. The magnetic array 200 can be used, for example, in a magnetic memory or the like.

[0031] Each write wiring WL electrically connects a power supply to one or more magnetoresistance effect elements 100. Each common wiring CL is a wiring used both when writing and reading data. Each common wiring CL electrically connects a reference potential to one or more magnetoresistance effect elements 100. The reference potential is, for example, ground. The common wiring CL may be provided for each of the multiple magnetoresistance effect elements 100, or may be provided across the multiple magnetoresistance effect elements 100. Each read wiring RL electrically connects a power supply to one or more magnetoresistance effect elements 100. The power supply is connected to the magnetic array 200 during use.

[0032] Each magnetoresistance effect element 100 is connected to a first switching element Sw1, a second switching element Sw2, and a third switching element Sw3, respectively. The first switching element Sw1 is connected between the magnetoresistance effect element 100 and a write wiring WL. The second switching element Sw2 is connected between the magnetoresistance effect element 100 and a common wiring CL. The third switching element Sw3 is connected to a read wiring RL that spans the multiple magnetoresistance effect elements 100.

[0033] When the first switching element Sw1 and the second switching element Sw2 are turned ON, a write current flows between the write line WL and the common line CL connected to a predetermined magnetoresistance effect element 100. When the second switching element Sw2 and the third switching element Sw3 are turned ON, a read current flows between the common line CL and the read line RL connected to a predetermined magnetoresistance effect element 100.

[0034] The first switching element Sw1, the second switching element Sw2, and the third switching element Sw3 are elements that control the flow of current. The first switching element Sw1, the second switching element Sw2, and the third switching element Sw3 are, for example, an element that uses a phase change of a crystal layer such as a transistor or an Ovonic Threshold Switch (OTS), an element that uses a change in band structure such as a Metal-Insulator Transition (MIT) switch, an element that uses a breakdown voltage such as a Zener diode or an avalanche diode, or an element whose conductivity changes with a change in atomic position.

[0035] 1, the magnetoresistance effect elements 100 connected to the same wiring share the third switching element Sw3. The third switching element Sw3 may be provided in each magnetoresistance effect element 100. That is, the third switching element Sw3 may be connected between the magnetoresistance effect element 100 and the read wiring RL. Also, the third switching element Sw3 may be provided in each magnetoresistance effect element 100, and the first switching element Sw1 or the second switching element Sw2 may be shared by the magnetoresistance effect elements 100 connected to the same wiring.

[0036] Fig. 2 is a cross-sectional view of a characteristic portion of the magnetic array 200 according to the first embodiment. Fig. 2 is a cross-section of the magnetoresistance effect element 100 cut along an xz plane passing through the center of the width in the y direction of the spin orbit torque wiring 20 described later.

[0037] The first switching element Sw1 and the second switching element Sw2 shown in Fig. 2 are transistors Tr. The third switching element Sw3 is electrically connected to the read wiring RL and is located, for example, in the -x direction in Fig. 2. The transistor Tr is, for example, a field effect transistor and has a gate electrode G, a gate insulating film GI, and a source S and a drain D formed in a substrate Sub. The substrate Sub is, for example, a semiconductor substrate.

[0038] The transistor Tr and the magnetoresistance effect element 100 are electrically connected through a via wiring V, a first conductive layer 41, and a second conductive layer 42. The transistor Tr and the write wiring WL or the common wiring CL are connected by the via wiring V. The via wiring V, the first conductive layer 41, and the second conductive layer 42 include a material having conductivity. The via wiring V extends, for example, in the z direction.

[0039] The magnetoresistance effect element 100 and the transistor Tr are covered with an insulating layer 90. The insulating layer 90 is an insulating layer that provides insulation between the wirings of the multilayer wiring and between the elements. The insulating layer 90 is made of, for example, silicon oxide (SiO x ), silicon nitride (SiN x ), silicon carbide (SiC), chromium nitride, silicon carbonitride (SiCN), silicon oxynitride (SiON), aluminum oxide (Al2O3), zirconium oxide (ZrO x ), magnesium oxide (MgO), aluminum nitride (AlN), etc.

[0040] Fig. 3 is a cross-sectional view of the magnetoresistance effect element 100. Fig. 3 is a cross-section of the magnetoresistance effect element 100 cut along an xz plane passing through the center of the y-direction width of the spin orbit torque wiring 20. Fig. 4 is a plan view of the magnetoresistance effect element 100.

[0041] The magnetoresistance effect element 100 includes, for example, a stack 10, a spin orbit torque line 20, and a spacer layer 30. The spin orbit torque line 20 is connected to a first conductive layer 41 and a second conductive layer 42. The first conductive layer 41 and the second conductive layer 42 are positioned to sandwich the stack 10 when viewed from the z direction. The stack 10 is connected to an electrode 43.

[0042] The periphery of the magnetoresistance effect element 100 is covered with insulating layers 91, 92, and 93. The insulating layers 91, 92, and 93 are part of the insulating layer 90 in FIG. 2. The insulating layer 91 is in the same layer as the first conductive layer 41 and the second conductive layer 42. The insulating layer 92 is in the same layer as the spin orbit torque wiring 20 and the spacer layer 30. The insulating layer 93 is in the same layer as the stack 10 and the electrode 43. The insulating layer 93 covers the side surface of the stack 10.

[0043] When writing data to the magnetoresistance effect element 100, a current is passed between the first conductive layer 41 and the second conductive layer 42 along the spin orbit torque wiring 20. When reading data from the magnetoresistance effect element 100, a current is passed between the first conductive layer 41 or the second conductive layer 42 and the electrode 43 along the stacking direction of the stack 10. The magnetoresistance effect element 100 is a magnetic element that utilizes spin orbit torque (SOT), and may be called a spin orbit torque type magnetoresistance effect element, a spin injection type magnetoresistance effect element, or a spin current magnetoresistance effect element.

[0044] The spin orbit torque wire 20 is an example of a wire. The spin orbit torque wire 20 extends in the x direction, for example, with the length in the x direction being longer than the y direction when viewed from the z direction. A write current flows in the x direction of the spin orbit torque wire 20. The spin orbit torque wire 20 is connected to the first ferromagnetic layer 1 side of the stack 10.

[0045] The spin-orbit torque wiring 20 generates a spin current by the spin Hall effect when a write current flows, and injects spin into the first ferromagnetic layer 1. The spin-orbit torque wiring 20 applies, for example, a spin-orbit torque (SOT) to the magnetization of the first ferromagnetic layer 1 that is sufficient to reverse the magnetization of the first ferromagnetic layer 1. The spin Hall effect is a phenomenon in which a spin current is induced in a direction perpendicular to the direction of current flow based on the spin-orbit interaction when a current flows. The spin Hall effect is similar to the normal Hall effect in that the direction of movement of moving charges (electrons) can be bent. In the normal Hall effect, the direction of movement of a charged particle moving in a magnetic field is bent by the Lorentz force. In contrast, in the spin Hall effect, the direction of movement of spin can be bent by the movement of electrons (current flow) even in the absence of a magnetic field.

[0046] For example, when a current flows through the spin orbit torque wiring 20, the first spins aligned in one direction and the second spins aligned in the opposite direction to the first spins are bent by the spin Hall effect in a direction perpendicular to the direction of the write current. For example, the first spins aligned in the -y direction are bent in the +z direction, and the second spins aligned in the +y direction are bent in the -z direction.

[0047] In nonmagnetic bodies (materials that are not ferromagnetic), the number of electrons of the first spin caused by the spin Hall effect is equal to the number of electrons of the second spin. In other words, the number of electrons of the first spin facing the +z direction is equal to the number of electrons of the second spin facing the -z direction. The first spins and second spins flow in a direction that eliminates the uneven distribution of spins. When the first spins and second spins move in the z direction, the flow of electric charges cancels each other out, so the amount of current is zero. Spin currents that do not involve electric currents are specifically called pure spin currents.

[0048] The flow of electrons of the first spin is J ↑ , the flow of electrons of the second spin is J ↓ , the spin current is J S Then, J S =J ↑ -J ↓ The spin current J Sis generated in the z direction. The first spins are injected from the spin orbit torque wiring 20 into the first ferromagnetic layer 1.

[0049] The spin-orbit torque wiring 20 includes any one of a metal, an alloy, an intermetallic compound, a metal boride, a metal carbide, a metal silicide, and a metal phosphide that has the function of generating a spin current by the spin Hall effect when a write current flows.

[0050] The spin orbit torque wiring 20 contains, for example, a nonmagnetic heavy metal as a main component. Heavy metal means a metal having a specific gravity equal to or greater than that of yttrium (Y). The nonmagnetic heavy metal is, for example, a nonmagnetic metal having a large atomic number of 39 or greater and having d electrons or f electrons in the outermost shell. The spin orbit torque wiring 20 is made of, for example, Hf, Ta, or W. The nonmagnetic heavy metal generates stronger spin orbit interactions than other metals. The spin Hall effect is generated by spin orbit interactions, and spins tend to be unevenly distributed in the spin orbit torque wiring 20, and a spin current J S is more likely to occur.

[0051] The spin orbit torque wiring 20 includes at least one selected from the group consisting of, for example, Ta, W, Pt, Au, Nb, Mo, Ru, Os, Rh, Ir, Pd, and Ag. The spin orbit torque wiring 20 is made of, for example, a simple metal of these elements. These elements have excellent thermal conductivity, and improve the heat dissipation of the magnetoresistance effect element 100.

[0052] The spin-orbit torque wiring 20 may also include a magnetic metal or a topological insulator. A topological insulator is a material in which the inside of the material is an insulator or a highly resistive material, but a spin-polarized metallic state occurs on the surface.

[0053] The spacer layer 30 is partially sandwiched between the stack 10 and the spin orbit torque line 20. The spacer layer 30 is, for example, stacked on the spin orbit torque line 20. The spacer layer 30 has an opening 31. The opening 31 is covered by the stack 10.

[0054] The spacer layer 30 is also present, for example, between the spin orbit torque wire 20 and the insulating layer 93. The spacer layer 30 has better heat dissipation properties than the insulating layer 93. When the spacer layer 30 having excellent heat dissipation properties extends to between the insulating layer 93 and the spin orbit torque wire 20, the heat dissipation properties of the magnetoresistive effect element 100 are improved.

[0055] The spacer layer 30 is, for example, a metal. The metal spacer layer 30 is, for example, Ru, Ta, Ir. The spacer layer 30 may also be an oxide, nitride or oxynitride. The oxide, nitride or oxynitride spacer layer 30 is, for example, MgO, Al2O4, Si3N4, SiON, etc.

[0056] The thickness of the spacer layer 30 may be substantially the same or different between the portion in contact with the laminate 10 and the portion not in contact with the laminate 10. The example shown in Fig. 3 is a case where the thickness of the spacer layer 30 is substantially the same between the portion in contact with the laminate 10 and the portion not in contact with the laminate 10. The example shown in Fig. 6 is a case where the thickness of the spacer layer 30 is different between the portion in contact with the laminate 10 and the portion not in contact with the laminate 10.

[0057] The thickness of the portion of the spacer layer 30 in contact with the stack 10 is, for example, thinner than the spin diffusion length of the spacer layer 30. The spin diffusion length is the distance that electrons can move while retaining spin information. If the thickness of the corresponding portion of the spacer layer 30 is equal to or less than the spin diffusion length of the spacer layer 30, spins can be efficiently injected from the spin orbit torque wiring 20 to the first ferromagnetic layer 1 even at a position sandwiching the spacer layer 30.

[0058] The thickness of the portion of the spacer layer 30 in contact with the stack 10 may be, for example, greater than the spin diffusion length of the spacer layer 30. When the spacer layer 30, which has superior thermal conductivity to the insulating layer 93, is thick, the heat dissipation of the magnetoresistive effect element 100 is improved.

[0059] The stack 10 is sandwiched in the z direction between the spin orbit torque wiring 20 and the electrode 43. The stack 10 is a columnar body. The shape of the stack 10 in plan view from the z direction is, for example, a circle, an ellipse, or a rectangle.

[0060] The stack 10 includes, for example, a first ferromagnetic layer 1, a second ferromagnetic layer 2, and a non-magnetic layer 3. The first ferromagnetic layer 1 is located closer to the spin orbit torque wiring 20. The first ferromagnetic layer 1 is in contact with the spin orbit torque wiring 20, for example, and is stacked on the spin orbit torque wiring 20. Spins are injected into the first ferromagnetic layer 1 from the spin orbit torque wiring 20. The magnetization of the first ferromagnetic layer 1 is subjected to a spin orbit torque (SOT) by the injected spins, and the orientation direction of the magnetization changes. The second ferromagnetic layer 2 is located in the z direction of the first ferromagnetic layer 1. The first ferromagnetic layer 1 and the second ferromagnetic layer 2 sandwich the non-magnetic layer 3 in the z direction.

[0061] The first ferromagnetic layer 1 and the second ferromagnetic layer 2 each have a magnetization. The magnetization of the second ferromagnetic layer 2 is less likely to change its orientation than the magnetization of the first ferromagnetic layer 1 when a predetermined external force is applied. The first ferromagnetic layer 1 is sometimes called a magnetization free layer, and the second ferromagnetic layer 2 is sometimes called a magnetization fixed layer or a magnetization reference layer. The resistance value of the laminate 10 changes depending on the difference in the relative angle of the magnetizations of the first ferromagnetic layer 1 and the second ferromagnetic layer 2 sandwiching the nonmagnetic layer 3 therebetween.

[0062] The magnetization easy axes of the first ferromagnetic layer 1 and the second ferromagnetic layer 2 may be in any direction on the xy plane or in the z direction. A ferromagnetic layer whose magnetization easy axis is in any direction on the xy plane is called an in-plane magnetization film, and a ferromagnetic material whose magnetization easy axis is in the z direction is called a perpendicular magnetization film.

[0063] The first ferromagnetic layer 1 includes a ferromagnetic material. The ferromagnetic material is, for example, a metal selected from the group consisting of Cr, Mn, Co, Fe, and Ni, an alloy containing one or more of these metals, or an alloy containing these metals and at least one of B, C, and N. The ferromagnetic material is, for example, a Co-Fe, Co-Fe-B, Ni-Fe, Co-Ho alloy, Sm-Fe alloy, Fe-Pt alloy, Co-Pt alloy, or CoCrPt alloy.

[0064] The first ferromagnetic layer 1 may include a Heusler alloy. The Heusler alloy includes an intermetallic compound having a chemical composition of XYZ or X2YZ. X is a transition metal element or a noble metal element of the Co, Fe, Ni, or Cu group on the periodic table, Y is a transition metal element or an element type of X of the Mn, V, Cr, or Ti group, and Z is a typical element of groups III to V. Examples of the Heusler alloy include Co2FeSi, Co2FeGe, Co2FeGa, Co2MnSi, Co2Mn 1-a Fe a Al b S 1-b , Co2FeGe 1-c Ga c etc. Heusler alloys have high spin polarizability.

[0065] The first surface 50 of the first ferromagnetic layer 1 has an overlapping surface 51 and a non-overlapping surface 52. The first surface 50 is the surface of the first ferromagnetic layer 1 on the spin orbit torque wiring 20 side. The overlapping surface 51 and the non-overlapping surface 52 have different heights in the z direction. There is, for example, a step between the overlapping surface 51 and the non-overlapping surface 52. There may be a slope between the overlapping surface 51 and the non-overlapping surface 52.

[0066] The overlapping surface 51 is a portion of the first surface 50 that overlaps with the spacer layer 30 when viewed from the z direction. In the cross section shown in Fig. 3, the overlapping surface 51 has a first overlapping region 511 and a second overlapping region 512. In the magnetoresistance effect element 100, the first overlapping region 511 and the second overlapping region 512 are different regions in the same spacer layer 30. The first overlapping region 511 and the second overlapping region 512 sandwich the midpoint of the stack 10 in the x direction.

[0067] The non-overlapping surface 52 is a portion of the first surface 50 that does not overlap with the spacer layer 30 when viewed from the z direction. The non-overlapping surface 52 is a portion that overlaps with the opening 31 in the z direction.

[0068] The area of ​​the non-overlapping surface 52 is, for example, larger than the area of ​​the overlapping surface 51. If the area of ​​the non-overlapping surface 52 is larger, the thermal stability of the magnetization of the first ferromagnetic layer 1 is increased. Conversely, as in the magnetoresistance effect element 100A shown in FIG 5, the area of ​​the overlapping surface 51 may be larger than the area of ​​the non-overlapping surface 52. If the area of ​​the non-overlapping surface 52 is small, the thermal stability of the magnetization of the first ferromagnetic layer 1 is reduced, and magnetization reversal becomes easier.

[0069] The second surface 55 of the first ferromagnetic layer 1 has an overlapping surface 56 and a non-overlapping surface 57. The overlapping surface 56 faces the overlapping surface 51. The non-overlapping surface 57 faces the non-overlapping surface 52. The second surface 55 faces the first surface 50 and reflects the shape of the first surface 50. The overlapping surface 56 and the non-overlapping surface 57 have different heights in the z direction. There is, for example, a step between the overlapping surface 56 and the non-overlapping surface 57. There may be a slope between the overlapping surface 56 and the non-overlapping surface 57.

[0070] The distance between the first surface 50 and the second surface 55 is approximately constant, for example, between overlapping surface 51 and overlapping surface 56 and between non-overlapping surface 52 and non-overlapping surface 57. In other words, the film thickness of the first ferromagnetic layer 1 is approximately constant. Approximately constant means that the difference in distance is 10% or less of the average distance.

[0071] The non-magnetic layer 3 includes a non-magnetic material. When the non-magnetic layer 3 is an insulator (when it is a tunnel barrier layer), its material may be, for example, Al2O3, SiO2, MgO, or MgAl2O4. In addition to these, materials in which a part of Al, Si, or Mg is replaced with Zn, Be, or the like may also be used. Among these, MgO and MgAl2O4 are materials that can realize coherent tunneling, so that spins can be efficiently injected. When the non-magnetic layer 3 is a metal, its material may be Cu, Au, Ag, or the like. Furthermore, when the non-magnetic layer 3 is a semiconductor, its material may be Si, Ge, CuInSe2, CuGaSe2, Cu(In,Ga)Se2, or the like.

[0072] The nonmagnetic layer 3 has a first portion 6 and a second portion 7. The first portion 6 is a portion that overlaps with the spacer layer 30 when viewed from the z direction. The second portion 7 is a portion that does not overlap with the spacer layer 30 when viewed from the z direction. The first portion 6 and the second portion 7 have different heights in the z direction. There is, for example, a step between the first portion 6 and the second portion 7. There may be a slope between the first portion 6 and the second portion 7.

[0073] The second ferromagnetic layer 2 contains the same material as the first ferromagnetic layer 1. The type of material applicable to the second ferromagnetic layer 2 may be the same as that of the first ferromagnetic layer 1, or the materials constituting the first ferromagnetic layer 1 and the second ferromagnetic layer 2 may be different.

[0074] The first surface 60 of the second ferromagnetic layer 2 has an overlapping surface 61 and a non-overlapping surface 62. The first surface 60 is the surface of the second ferromagnetic layer 2 on the spin orbit torque wiring 20 side. The overlapping surface 61 and the non-overlapping surface 62 have different heights in the z direction. There is, for example, a step between the overlapping surface 61 and the non-overlapping surface 62. There may be a slope between the overlapping surface 61 and the non-overlapping surface 62.

[0075] The overlapping surface 61 is a portion of the first surface 60 that overlaps with the spacer layer 30 when viewed from the z direction. The non-overlapping surface 62 is a portion of the first surface 60 that does not overlap with the spacer layer 30 when viewed from the z direction. The non-overlapping surface 62 is a portion that overlaps with the opening 31 in the z direction.

[0076] The second surface 65 of the second ferromagnetic layer 2 has an overlapping surface 66 and a non-overlapping surface 67. The overlapping surface 66 faces the overlapping surface 61. The non-overlapping surface 67 faces the non-overlapping surface 62. The second surface 65 faces the first surface 60 and reflects the shape of the first surface 60. The overlapping surface 66 and the non-overlapping surface 67 have different heights in the z direction. There is, for example, a step between the overlapping surface 66 and the non-overlapping surface 67. There may be a slope between the overlapping surface 66 and the non-overlapping surface 67.

[0077] The second surface 65 is a surface in contact with the electrode 43. When the second surface 65 has an overlapping surface 66 and a non-overlapping surface 67 at different positions in the z direction, the contact area between the second ferromagnetic layer 2 and the electrode 43 becomes large. As a result, the adhesion and thermal conductivity between the second ferromagnetic layer 2 and the electrode 43 are improved.

[0078] The distance between the first surface 60 and the second surface 65 is approximately constant, for example, between the overlapping surface 61 and the overlapping surface 66 and between the non-overlapping surface 62 and the non-overlapping surface 67. In other words, the film thickness of the second ferromagnetic layer 2 is approximately constant.

[0079] The laminate 10 may have an antiferromagnetic layer on the surface of the second ferromagnetic layer 2 opposite to the nonmagnetic layer 3, with a spacer layer interposed between them. The second ferromagnetic layer 2, the spacer layer, and the antiferromagnetic layer form a synthetic antiferromagnetic structure (SAF structure). The synthetic antiferromagnetic structure is composed of two magnetic layers sandwiching a nonmagnetic layer. The second ferromagnetic layer 2 and the antiferromagnetic layer are antiferromagnetically coupled, so that the coercive force of the second ferromagnetic layer 2 is larger than that of a layer without an antiferromagnetic layer. The antiferromagnetic layer is, for example, IrMn, PtMn, or the like. The spacer layer includes, for example, at least one selected from the group consisting of Ru, Ir, and Rh.

[0080] The stack 10 may have layers other than the first ferromagnetic layer 1, the second ferromagnetic layer 2, and the nonmagnetic layer 3. For example, an underlayer may be provided between the spin orbit torque wiring 20 and the stack 10. The underlayer enhances the crystallinity of each layer constituting the stack 10.

[0081] Next, an example of a method for manufacturing the magnetoresistance effect element 100 according to this embodiment will be described. The magnetoresistance effect element 100 is formed by a lamination process of each layer and a processing process of processing a part of each layer into a predetermined shape. The lamination of each layer can be performed using a sputtering method, a chemical vapor deposition (CVD) method, an electron beam deposition method (EB deposition method), an atomic laser deposition method, or the like. The processing of each layer can be performed using photolithography, or the like.

[0082] First, impurities are doped into predetermined positions of the substrate Sub to form a source S and a drain D. Next, a gate insulating film GI and a gate electrode G are formed between the source S and the drain D. The source S, the drain D, the gate insulating film GI, and the gate electrode G form a transistor Tr. The substrate Sub may be a commercially available product with a transistor Tr formed thereon.

[0083] Next, an insulating layer 90 is formed so as to cover the transistor Tr. An opening is formed in the insulating layer 90, and the opening is filled with a conductor to form the via wiring V, the first conductive layer 41, and the second conductive layer 42. The write wiring WL and the common wiring CL are formed by laminating the insulating layer 90 to a predetermined thickness, forming a groove in the insulating layer 90, and filling the groove with a conductor.

[0084] Next, a wiring layer is laminated on the upper surfaces of the insulating layer 90, the first conductive layer 41, and the second conductive layer 42. A resist is formed in a predetermined position of the wiring layer, and a non-magnetic layer is formed on top of it. The wiring layer and the non-magnetic layer are processed into a predetermined shape, and the resist is lifted off. The wiring layer becomes the spin orbit torque wiring 20, and the non-magnetic layer becomes the spacer layer 30. The periphery of the spin orbit torque wiring 20 and the spacer layer 30 is covered with an insulating layer 92.

[0085] Next, a ferromagnetic layer, a nonmagnetic layer, a ferromagnetic layer, and a hard mask layer are stacked in this order. The ferromagnetic layer, the nonmagnetic layer, and the ferromagnetic layer are processed into a predetermined shape at once through the hard mask layer to obtain a stack 10. The stack is then filled with an insulating layer 93, and an electrode 43 is formed to obtain a magnetoresistance effect element 100.

[0086] Next, a description will be given of the operation of the magnetoresistance effect element 100 according to the first embodiment. The magnetoresistance effect element 100 has a data write operation and a data read operation.

[0087] First, the operation of recording data in the magnetoresistance effect element 100 will be described. First, the first switching element Sw1 and the second switching element Sw2 connected to the magnetoresistance effect element 100 to which data is to be recorded are turned ON. When the first switching element Sw1 and the second switching element 120 are set to Sw2, a write current flows in the spin orbit torque wiring 20. When a write current flows in the spin orbit torque wiring 20, a spin Hall effect occurs, and spins are injected into the first ferromagnetic layer 1. The spins injected into the first ferromagnetic layer 1 apply a spin orbit torque (SOT) to the magnetization of the first ferromagnetic layer 1, changing the orientation of the magnetization of the first ferromagnetic layer 1. When the direction of the current flow is reversed, the direction of the spins injected into the first ferromagnetic layer 1 is reversed, so that the orientation of the magnetization can be freely controlled.

[0088] The resistance value in the stacking direction of the stack 10 is small when the magnetization of the first ferromagnetic layer 1 and the magnetization of the second ferromagnetic layer 2 are parallel, and is large when the magnetization of the first ferromagnetic layer 1 and the magnetization of the second ferromagnetic layer 2 are antiparallel. Data is recorded in the magnetoresistance effect element 100 as the resistance value in the stacking direction of the stack 10.

[0089] Next, the operation of reading data from the magnetoresistance effect element 100 will be described. First, the second switching element Sw2 and the third switching element Sw3 connected to the magnetoresistance effect element 100 to which data is to be recorded are turned ON. When each switching element is set in this way, a read current flows in the stacking direction of the laminate 10. According to Ohm's law, if the resistance value in the stacking direction of the laminate 10 differs, the output voltage differs. Therefore, for example, by reading the voltage in the stacking direction of the laminate 10, the data recorded in the magnetoresistance effect element 100 can be read.

[0090] The magnetoresistance effect element 100 according to the first embodiment has an overlapping surface 51 and a non-overlapping surface 52 where the first ferromagnetic layer 1 contacts the spacer layer 30. The stability of the magnetization of the first ferromagnetic layer 1 is affected by the configuration of the underlying layer to be formed, the crystal structure, the thickness of the first ferromagnetic layer 1, and the like. In addition, the orientation direction of the magnetization tends to be disturbed in the vicinity of the step between the overlapping surface 51 and the non-overlapping surface 52. The part where the orientation direction of the magnetization is disturbed is more likely to undergo magnetization reversal than other parts. Therefore, in the magnetoresistance effect element 100 according to the first embodiment, the magnetization reversal progresses due to the part where the magnetization is easily reversed, so that the reversal current density can be reduced. When the reversal current density of each magnetoresistance effect element 100 is reduced, the power consumption of the entire magnetic array 200 is reduced.

[0091] "Second embodiment" 6 is a cross-sectional view of the magnetoresistance effect element 101 according to the second embodiment. In the magnetoresistance effect element 101 according to the second embodiment, the same components as those in the magnetoresistance effect element 100 according to the first embodiment are denoted by the same reference numerals and will not be described.

[0092] The magnetoresistance effect element 101 includes a stack 10A, a spin orbit torque wiring 20, and a spacer layer 30A.

[0093] The spacer layer 30A is on the spin orbit torque wiring 20. The spacer layer 30A is between the spin orbit torque wiring 20 and the stack 10 or the insulating layer 93. The spacer layer 30A has a first portion 30A1 and a second portion 30A2. The first portion 30A1 is a portion that overlaps with the stack 10 in the z direction. The second portion 30A2 is a portion that does not overlap with the stack 10 in the z direction. The spacer layer 30A has an opening 31A. The opening 31A is covered by the stack 10A.

[0094] The thickness of the first portion 30A1 becomes thinner with increasing distance from the boundary between the first portion 30A1 and the second portion 30A2. The average thickness of the first portion 30A1 is thinner than the average thickness of the second portion 30A2.

[0095] The laminate 10A includes a first ferromagnetic layer 1A, a second ferromagnetic layer 2A, and a nonmagnetic layer 3A. The materials constituting the first ferromagnetic layer 1A, the second ferromagnetic layer 2A, and the nonmagnetic layer 3A are similar to those of the first ferromagnetic layer 1, the second ferromagnetic layer 2, and the nonmagnetic layer 3, respectively.

[0096] The first surface 50A of the first ferromagnetic layer 1A has an overlapping surface 51A and a non-overlapping surface 52A. The overlapping surface 51A overlaps with the spacer layer 30A when viewed from the z direction. The non-overlapping surface 52A does not overlap with the spacer layer 30A when viewed from the z direction. The first surface 50A is curved such that the non-overlapping surface 52A is located closer to the spin orbit torque wiring 20 than the overlapping surface 51A. The second surface 55A of the first ferromagnetic layer 1A is also curved in the same direction as the first surface 50A.

[0097] The nonmagnetic layer 3A has a first portion 6A and a second portion 7A. The first portion 6A overlaps with the spacer layer 30 when viewed in the z direction. The second portion 7A does not overlap with the spacer layer 30 when viewed in the z direction. The nonmagnetic layer 3A is curved such that the second portion 7A is located closer to the spin orbit torque wiring 20 than the first portion 6A.

[0098] The first surface 60A and the second surface 65A of the second ferromagnetic layer 2A are curved in the same direction as the first surface 50A of the first ferromagnetic layer 1A.

[0099] The magnetoresistance effect element 101 according to the second embodiment can provide the same effects as the magnetoresistance effect element 100 according to the first embodiment. In addition, by inclining the upper surface of the first portion 30A1 of the spacer layer 30A, the orientation direction of the magnetization in the vicinity of the overlapping surface 51A is disturbed from the magnetization easy axis direction of the first ferromagnetic layer 1, and the reversal current density can be further reduced.

[0100] "Third embodiment" 7 is a cross-sectional view of the magnetoresistance effect element 102 according to the third embodiment. In the magnetoresistance effect element 102 according to the third embodiment, the same components as those in the magnetoresistance effect element 100 according to the first embodiment are denoted by the same reference numerals and will not be described.

[0101] The magnetoresistance effect element 101 includes a stack 10B, a spin orbit torque wiring 20, and a spacer layer 30.

[0102] The laminate 10B includes a first ferromagnetic layer 1B, a second ferromagnetic layer 2B, and a nonmagnetic layer 3B. The materials constituting the first ferromagnetic layer 1B, the second ferromagnetic layer 2B, and the nonmagnetic layer 3B are the same as those of the first ferromagnetic layer 1, the second ferromagnetic layer 2, and the nonmagnetic layer 3, respectively.

[0103] The second surface 55B of the first ferromagnetic layer 1B does not reflect the shape of the first surface 50. The second surface 55B is a substantially flat surface. The distance between the overlapping surface 51 and the second surface 55B is different from the distance between the non-overlapping surface 52 and the second surface 55B. That is, the thickness of the first ferromagnetic layer 1B differs between the position overlapping with the spacer layer 30 and the position not overlapping with the spacer layer 30.

[0104] The nonmagnetic layer 3B is a flat surface extending in the xy directions, reflecting the shape of the second surface 55B of the first ferromagnetic layer 1B. The second ferromagnetic layer 2B is also a flat surface extending in the xy directions, reflecting the shape of the second surface 55B of the first ferromagnetic layer 1B.

[0105] The magnetoresistance effect element 102 according to the third embodiment provides the same effects as the magnetoresistance effect element 100 according to the first embodiment. The orientation direction of magnetization changes depending on the film thickness of the magnetic material. For example, CoFeB may become a perpendicular magnetization film or an in-plane magnetization film depending on the film thickness. Since the film thickness of the first ferromagnetic layer 1B varies depending on the location, the stability of magnetization varies depending on the location in the x direction. Therefore, the magnetoresistance effect element 102 according to the third embodiment can further reduce the reversal current density.

[0106] Furthermore, if the thickness of the second ferromagnetic layer 2B is substantially constant, the stability of the magnetization of the second ferromagnetic layer 2B is increased. If the magnetization stability of the second ferromagnetic layer 2B is increased, the magnetoresistance change rate (MR ratio) of the magnetoresistance effect element 102 is improved.

[0107] "Fourth embodiment" Fig. 8 is a cross-sectional view of the magnetoresistance effect element 103 according to the fourth embodiment. Fig. 9 is a plan view of the magnetoresistance effect element 103 according to the fourth embodiment. In the magnetoresistance effect element 103 according to the fourth embodiment, the same components as those in the magnetoresistance effect element 100 according to the first embodiment are denoted by the same reference numerals and description thereof will be omitted.

[0108] The magnetoresistance effect element 103 includes a stack 10C, a spin orbit torque wiring 20, and a spacer layer 30C.

[0109] The spacer layer 30C is located only on the first conductive layer 41 side from the center of the stack 10C in the x direction.

[0110] The laminate 10C includes a first ferromagnetic layer 1C, a second ferromagnetic layer 2C, and a nonmagnetic layer 3C. The materials constituting the first ferromagnetic layer 1C, the second ferromagnetic layer 2C, and the nonmagnetic layer 3C are similar to those of the first ferromagnetic layer 1, the second ferromagnetic layer 2, and the nonmagnetic layer 3, respectively.

[0111] The first surface 50C of the first ferromagnetic layer 1C has an overlapping surface 51C and a non-overlapping surface 52C. The overlapping surface 51C overlaps with the spacer layer 30C when viewed from the z direction. The non-overlapping surface 52C does not overlap with the spacer layer 30C when viewed from the z direction. The overlapping surface 51C and the non-overlapping surface 52C are located at different positions in the z direction. There is a step or a slope between the overlapping surface 51C and the non-overlapping surface 52C. The film thickness of the first ferromagnetic layer 1C is approximately constant.

[0112] The nonmagnetic layer 3C has a first portion 6C and a second portion 7C. The first portion 6C is a portion that overlaps with the spacer layer 30C when viewed from the z direction. The second portion 7C is a portion that does not overlap with the spacer layer 30C when viewed from the z direction. The first portion 6C and the second portion 7C have different heights in the z direction. There is, for example, a step between the first portion 6C and the second portion 7C. There may be a slope between the first portion 6C and the second portion 7C.

[0113] The second ferromagnetic layer 2C has a first surface 60C and a second surface 65C. The shapes of the first surface 60C and the second surface 65C reflect the shape of the first surface 50C of the first ferromagnetic layer 1C. The first surface 60C has an overlapping surface 61C and a non-overlapping surface 62C, which are located at different height positions in the z direction. The second surface 65C has an overlapping surface 66C and a non-overlapping surface 67C, which are located at different height positions in the z direction.

[0114] The magnetoresistance effect element 103 according to the fourth embodiment provides the same effects as the magnetoresistance effect element 100 according to the first embodiment.

[0115] "Fifth embodiment" 10 is a plan view of the magnetoresistance effect element 104 according to the fifth embodiment. In the magnetoresistance effect element 104 according to the fifth embodiment, the same components as those in the magnetoresistance effect element 100 according to the first embodiment are denoted by the same reference numerals and will not be described.

[0116] The magnetoresistance effect element 104 includes a stack 10D, a spin orbit torque wiring 20, and spacer layers 30D and 30E. The cross-sectional shape of the magnetoresistance effect element 104 is substantially the same as that shown in FIG.

[0117] The spacer layer 30D is located only on the first conductive layer 41 side from the center of the stack 10D in the x direction. The spacer layer 30E is located only on the second conductive layer 42 side from the center of the stack 10D in the x direction.

[0118] The first surface of the first ferromagnetic layer of the laminate 10D has overlapping surfaces 51D and 51E and a non-overlapping surface 52D. The overlapping surface 51D overlaps with the spacer layer 30D when viewed from the z direction. The overlapping surface 51E overlaps with the spacer layer 30E when viewed from the z direction. The non-overlapping surface 52D does not overlap with the spacer layers 30D and 30E when viewed from the z direction. The overlapping surfaces 51D and 51E are located at different positions in the z direction from the non-overlapping surface 52E. The overlapping surface 51D corresponds to the first overlapping region 511, and the overlapping surface 51E corresponds to the second overlapping region 512. The overlapping surfaces 51D and 51E sandwich the midpoint of the laminate 10 in the x direction between them.

[0119] The magnetoresistance effect element 104 according to the fifth embodiment provides the same effects as the magnetoresistance effect element 100 according to the first embodiment.

[0120] Sixth embodiment 11 is a cross-sectional view of the magnetization rotation element 110 according to the sixth embodiment. The magnetization rotation element 110 differs from the magnetoresistive effect element 100 according to the first embodiment in that the magnetization rotation element 110 does not have a nonmagnetic layer 3 and a second ferromagnetic layer 2. In the magnetization rotation element 110 according to the sixth embodiment, the same components as those in the magnetoresistive effect element 100 according to the first embodiment are denoted by the same reference numerals and will not be described.

[0121] The magnetization rotation element 110, for example, irradiates light to the first ferromagnetic layer 1 and evaluates the light reflected by the first ferromagnetic layer 1. When the orientation direction of magnetization changes due to the magnetic Kerr effect, the polarization state of the reflected light changes. The magnetization rotation element 110 can be used as an optical element, for example, in an image display device, utilizing the difference in the polarization state of light.

[0122] In addition, the magnetization rotating element 110 can be used alone as an anisotropic magnetic sensor, an optical element utilizing the magnetic Faraday effect, or the like.

[0123] The magnetization rotation element 110 includes a spin-orbit torque wiring 20 , a first ferromagnetic layer 1 , and a spacer layer 30 .

[0124] The magnetization rotation element 110 according to the sixth embodiment has an overlapping surface 51 and a non-overlapping surface 52 where the first ferromagnetic layer 1 contacts the spacer layer 30. Therefore, similar to the magnetoresistance effect element 100 according to the first embodiment, magnetization reversal progresses starting from a portion where magnetization reversal is easy to occur, so that the current required for magnetization rotation can be reduced.

[0125] Although the preferred aspects of the present invention have been illustrated based on the first to sixth embodiments, the present invention is not limited to these embodiments. For example, the characteristic configurations of each embodiment may be applied to the other embodiments. [Explanation of symbols]

[0126] 1,1A,1B,1C...first ferromagnetic layer 2,2A,2B,2C…Second ferromagnetic layer 3,3A,3B,3C…Nonmagnetic layer 6,6A,6C…1st part 7,7A,7C…Second part 10, 10A, 10B, 10C, 10D...Laminate 20…Spin-orbit torque wiring 30, 30A, 30C, 30D, 30E...Spacer layer 31,31A…Aperture 50,50A,50C…First side 51, 51A, 51C, 51D, 51E...overlapping surfaces 52, 52A, 52C, 52D, 52E...Non-overlapping surfaces 93...Insulating layer 100, 100A, 101, 102, 103, 104...Magnetoresistance effect element 110...Magnetized rotating element 200…Magnetic array 511…First overlapping area 512…Second overlapping area

Claims

1. a stack including a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer; a spin orbit torque wiring connected to the first ferromagnetic layer side of the stack; a spacer layer partially sandwiched between the stack and the spin-orbit torque wiring; a write current is passed along the spin orbit torque wiring to inject spin into the first ferromagnetic layer, thereby changing the orientation direction of the magnetization of the first ferromagnetic layer; a first surface of the first ferromagnetic layer on the spin orbit torque wiring side has an overlapping surface that overlaps with the spacer layer when viewed from a stacking direction of the stack, and a non-overlapping surface that does not overlap with the spacer layer when viewed from the stacking direction, The overlapping surface and the non-overlapping surface have different heights in the stacking direction, The area of ​​the overlapping surface is larger than the area of ​​the non-overlapping surface, the thickness of the spacer layer is substantially the same in a portion in contact with the laminate and a portion not in contact with the laminate; A magnetoresistance effect element having a step between the overlapping surface and the non-overlapping surface.

2. the spacer layer has an opening; The magnetoresistive element according to claim 1 , wherein the laminate covers the opening.

3. In a cross section along a first direction in which the spin orbit torque wiring extends and along the stacking direction, the overlapping surface has a first overlapping region and a second overlapping region, The magnetoresistance effect element according to claim 1 , wherein the first overlapping region and the second overlapping region are located on either side of a midpoint of the stack in the first direction.

4. the nonmagnetic layer has a first portion overlapping with the spacer layer when viewed from the stacking direction, and a second portion not overlapping with the spacer layer when viewed from the stacking direction, 4. The magnetoresistance effect element according to claim 1, wherein the first portion and the second portion have different heights in the stacking direction.

5. the nonmagnetic layer has a first portion overlapping with the spacer layer when viewed from the stacking direction, and a second portion not overlapping with the spacer layer when viewed from the stacking direction, 5. The magnetoresistive element according to claim 1, wherein the nonmagnetic layer is curved such that the second portion is closer to the spin orbit torque wiring than the first portion.

6. an insulating layer covering a side surface of the stack and the spin orbit torque wiring; 6. The magnetoresistive element according to claim 1, wherein the spacer layer is between the insulating layer and the spin orbit torque wiring.

7. 7. The magnetoresistance effect element according to claim 1, wherein a thickness of the portion of said spacer layer in contact with said stack is greater than a spin diffusion length of said spacer layer.

8. 7. The magnetoresistance effect element according to claim 1, wherein a thickness of the portion of said spacer layer in contact with said stack is smaller than a spin diffusion length of said spacer layer.

9. 9. The magnetoresistance effect element according to claim 1, wherein the spacer layer is made of a metal.

10. 9. The magnetoresistance effect element according to claim 1, wherein the spacer layer is an oxide, a nitride or an oxynitride.

11. A magnetic array comprising a plurality of magnetoresistance effect elements according to any one of claims 1 to 10.

12. A first ferromagnetic layer; a spin-orbit torque wiring connected to the first ferromagnetic layer; a spacer layer partially sandwiched between the first ferromagnetic layer and the spin-orbit torque wiring; a first surface of the first ferromagnetic layer on the spin orbit torque wiring side has an overlapping surface overlapping with the spacer layer as viewed from a stacking direction of the first ferromagnetic layer, and a non-overlapping surface not overlapping with the spacer layer as viewed from the stacking direction; The overlapping surface and the non-overlapping surface have different heights in the stacking direction, The area of ​​the overlapping surface is larger than the area of ​​the non-overlapping surface, the thickness of the spacer layer is substantially the same in a portion in contact with the laminate and a portion not in contact with the laminate; A magnetized rotating element having a step between the overlapping surface and the non-overlapping surface.

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