Track electronic device based on track Hall effect and preparation method thereof

Abstract

The invention provides an orbital electronics device based on an orbital Hall effect and a preparation method thereof. The orbital electronics device comprises a substrate; the sensor comprises a substrate and a ferromagnetic / non-magnetic heterojunction structure prepared on the substrate, the ferromagnetic / non-magnetic heterojunction structure comprises a ferromagnetic layer structure and a non-ferromagnetic layer structure serving as a track Hall layer, the ferromagnetic layer structure is located on the face, away from the substrate, of the non-ferromagnetic layer structure, and the ferromagnetic layer structure has perpendicular magnetic anisotropy; wherein the non-ferromagnetic layer structure serving as the orbit Hall layer is formed by doping an oxide or metal (second metal) into an orbit Hall channel layer (first metal or two-dimensional transition metal sulfide (TMD) material). According to the invention, the oxide or metal is doped as the orbit Hall layer, so that the orbit torque efficiency can be enhanced, and the critical flip current density can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic devices, and in particular to a track electronic device based on track Hall effect and a preparation method thereof. Background Art

[0002] As we all know, effective current-induced spin torque effect is of great significance for the development of spintronic memory and logic devices. In the past few decades, the study of spin orbit torque (SOT) has received widespread attention. It uses the spin Hall effect (SHE) to realize the conversion of charge flow-spin flow. Compared with charge flow, spin flow has the great advantage of no Joule heat dissipation. The spin Hall effect has been applied in many materials, such as heavy metal materials such as tungsten, tantalum and platinum. When heavy metal materials are used as spin sources, the spin Hall effect uses the strong spin-orbit coupling (SOC) of heavy metal materials themselves to generate spin flow and induced torque to manipulate the magnetic moment of the adjacent ferromagnetic layer (FM). However, heavy metal materials have problems in practical device applications because their high resistivity makes such devices less efficient. In addition, heavy elements are usually expensive and often not suitable for large-scale production. The use of heavy metals limits the choice of spin source materials.

[0003] Recently, based on theoretical predictions and experimental results, it has been proposed to use electric fields to generate orbital currents, namely the orbital Hall effect (OHE). Similar to the spin Hall effect, orbital currents carry angular momentum like spin currents, so injecting orbital currents into the ferromagnetic layer can produce torque on the local magnetic moment of the ferromagnetic layer. This type of torque caused by orbital current injection is called orbital torque (OT). Orbital torque provides an experimental method to detect OHE, and orbital torque OT has aroused great interest. The maximum angular momentum of each electronic state caused by spin current is is the simplified Planck constant, while the orbital flow has no restrictions on the angular momentum of an electronic state, indicating that the efficiency of OT is more significant. Theoretical calculations show that in many materials, the orbital Hall conductivity is much larger than the spin Hall conductivity. This indicates that the spin torque caused by OHE can be larger than the spin torque caused by SHE, thereby improving the spin torque efficiency of spintronic devices. In addition, since OHE originates from the momentum space orbital texture, spin-orbit coupling (SOC) is not required, making the material selection of the orbital source very wide, rather than limited to a few heavy metals.

[0004] Currently, 3d-5d metal materials or two-dimensional transition metal sulfide (TMD) materials such as Ti and Zr have begun to be used to prepare orbital electronic devices. However, how to further optimize the orbital torque efficiency of orbital electronic devices based on 3d-5d metal materials or two-dimensional transition metal sulfide (TMD) materials to obtain orbital electronic devices with higher performance is a problem that is being paid attention to and studied but has not yet been broken through. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides an orbital electronics device based on the orbital Hall effect and a preparation method thereof, so as to optimize the orbital torque efficiency of orbital electronics devices based on 3d-5d metal materials or two-dimensional transition metal sulfide (TMD) materials, thereby ensuring that the orbital electronics device has excellent performance while reducing costs.

[0006] One aspect of the present invention provides a track electronics device based on track Hall effect, the track electronics device comprising:

[0007] Substrate; and a ferromagnetic / non-magnetic heterojunction structure prepared on the substrate;

[0008] Wherein, the ferromagnetic / non-magnetic heterojunction structure includes a ferromagnetic layer structure and a non-ferromagnetic layer serving as an orbital Hall layer, and the ferromagnetic layer structure is located on a side of the non-ferromagnetic layer structure away from the substrate; wherein, the orbital Hall layer is a doped orbital Hall layer formed by doping an oxide or a second metal into a first metal or a two-dimensional transition metal sulfide (TMD) material, and the first metal is a 3d-5d metal material.

[0009] In some embodiments of the present invention, the track electronics device further comprises: a protective layer formed on the ferromagnetic / non-magnetic heterojunction structure.

[0010] In some embodiments of the present invention, the oxide is magnesium oxide, titanium oxide, ruthenium oxide, gadolinium oxide or copper oxide; the second metal is selected from one of the following metals: Gd, Pt, W, Au, Hf, Ta, Pd, Ir, Bi, Re, Ru or Rh; the first metal is selected from the following orbital source and the non-ferromagnetic layer is selected from one of the following materials: Ti, Zr, Mn, Cr, Al, Ge, Ta, W; the two-dimensional transition metal sulfide (TMD) material is one of the following materials: WTe2, MoS2, WSe2, WS, TaTe2, MoTe2, NbSe2, PtTe2 or TaS2.

[0011] In some embodiments of the present invention, the ferromagnetic layer structure is a ferromagnetic multi-film layer formed by multiple material layers, a ferromagnetic single film layer formed by multiple materials, or a two-dimensional ferromagnetic material layer.

[0012] In some embodiments of the present invention, the ferromagnetic single film layer formed by the multiple materials is a CoFeB layer, a Co layer, a Ni layer, a CoNi alloy layer, a CoPt alloy layer, a CoGd alloy layer, a CoPd alloy layer or a CoTb alloy layer; the multi-film layer formed by the multiple material layers is: a CoFeB / Gd / CoFeB multi-film layer, a CoFeB / Tb / CoFeB multi-film layer, a multi-film layer composed of multiple Co / Pt double-film layers, a multi-film layer composed of multiple Co / Pd double-film layers, a multi-film layer composed of multiple Co / Gd double-film layers, a multi-film layer composed of multiple Co / Tb double-film layers or a multi-film layer composed of multiple Co / Ni double-film layers; wherein the CoFeB / Gd / CoFeB multi-film layer consists of CoFeB layer, Gd layer and CoFeB layer; the CoFeB / Tb / CoFeB multi-film layer consists of CoFeB layer, Tb layer and CoFeB layer; the Co / Pt double film layer consists of Co layer and Pt layer; the Co / Pd double film layer consists of Co layer and Pd layer; the Co / Gd double film layer consists of Co layer and Gd layer; the Co / Tb double film layer consists of Co layer and Tb layer; the Co / Ni double film layer consists of Co layer and Ni layer; or the two-dimensional ferromagnetic material is MnBi2Te4, Fe3GeTe2, Cr2Ge2Te6, Fe5GeTe2 or Fe3GaTe2.

[0013] In some embodiments of the present invention, the ferromagnetic layer structure is an artificial antiferromagnetic layer or an artificial ferromagnetic layer.

[0014] In some embodiments of the present invention, the artificial antiferromagnetic layer or the artificial ferromagnetic layer includes a first ferromagnetic layer, a second ferromagnetic layer and a spacer layer between the first ferromagnetic layer and the second ferromagnetic layer, and the spacer layer is a non-magnetic layer.

[0015] In some embodiments of the present invention, the first ferromagnetic layer is a ferromagnetic layer with a larger orbital-spin conversion coefficient, and the second ferromagnetic layer is a ferromagnetic layer with a smaller orbital-spin conversion coefficient and a low damping constant.

[0016] In some embodiments of the present invention, the ferromagnetic layer structure is used as a magnetic free layer; the track electronics device further comprises:

[0017] a nonmagnetic barrier layer formed on a side of the magnetic free layer away from the substrate; and

[0018] A fixed layer formed on a side of the non-magnetic barrier layer away from the magnetic free layer, wherein the fixed layer is a ferromagnetic layer;

[0019] The magnetic free layer, the nonmagnetic barrier layer and the fixed layer form a magnetic tunnel junction.

[0020] In some embodiments of the present invention, the material of the non-magnetic barrier layer is selected from MgO, Al2O3, NiO, TiO x , BN, WSe2 two-dimensional semiconductors; the fixed layer is selected from one or more of NiFe, FePd, FePt, CoPd, CoPt, CoFeB, CoFeB / Gd / CoFeB or CoFeB / Tb / CoFeB films.

[0021] In some embodiments of the present invention, the first ferromagnetic layer in the artificial antiferromagnetic layer is one of the following single-layer ferromagnetic materials or multi-layer ferromagnetic materials: CoFeB, FePd, [Co / Ni] n 、[Co / Pd] n or [Co / Pt] n The second ferromagnetic layer is selected from CoFeB, FePd, [Co / Ni] n 、[Co / Pd] n or [Co / Pt] n One of the following, wherein n represents the number of times the [Co / Pd] double film layer, the [Co / Pt] double film layer and the [Co / Ni] double film layer are repeatedly stacked, and n is greater than 1.

[0022] In some embodiments of the present invention, the thickness of the non-ferromagnetic layer structure is 2-20 nanometers; the thickness of the ferromagnetic layer structure is 1-20 nanometers.

[0023] Another aspect of the present invention further provides a magnetic random access memory, the magnetic random access memory comprising a basic storage unit based on a magnetic tunnel junction, the basic storage unit comprising:

[0024] substrate;

[0025] Doped orbital Hall layer fabricated on substrate

[0026] A magnetic free layer, which is located on a side of the doped orbital Hall layer away from the substrate, and the magnetic free layer has perpendicular magnetic anisotropy;

[0027] a nonmagnetic barrier layer formed on a side of the magnetic free layer away from the substrate; and

[0028] A fixed layer formed on a side of the non-magnetic barrier layer away from the magnetic free layer, wherein the fixed layer is a ferromagnetic layer;

[0029] The doped orbital Hall layer is formed by doping oxide or a second metal into a first metal or a two-dimensional transition metal sulfide (TMD) material, and the first metal is a 3d-5d metal material; the magnetic free layer, the nonmagnetic barrier layer and the fixed layer form a magnetic tunnel junction.

[0030] Another aspect of the present invention provides a method for preparing an orbital electronics device based on the orbital Hall effect, the method comprising: growing a doped orbital Hall layer as a non-ferromagnetic layer structure on a substrate by magnetron sputtering, the doped orbital Hall layer being obtained by doping an oxide or a second metal into a first metal or a two-dimensional transition metal sulfide (TMD) material by magnetron sputtering, wherein the first metal is a 3d-5d metal material suitable for use as an orbital source; and growing a ferromagnetic layer structure on the non-ferromagnetic layer structure by magnetron sputtering, the thickness and composition ratio of each layer structure in the ferromagnetic layer of the ferromagnetic layer structure being adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy; wherein the ferromagnetic layer structure and the non-ferromagnetic layer structure serving as the orbital Hall layer form a ferromagnetic / non-magnetic heterojunction structure.

[0031] The orbital electronics device based on the orbital Hall effect of the present invention and the preparation method thereof use 3d-5d metal materials or two-dimensional transition metal sulfide (TMD) materials as orbital source materials, thereby removing the restrictions on the selection of material orbital sources; and the 3d-5d metal materials or two-dimensional transition metal sulfide (TMD) materials are doped to enhance the orbital torque efficiency, thereby realizing orbital torque reversal, so that the prepared orbital electronics device is not only low-cost but also has good performance.

[0032] Additional advantages, purposes, and features of the present invention will be described in part in the following description, and will become apparent to those skilled in the art after studying the following, or may be learned from the practice of the present invention. The purposes and other advantages of the present invention may be achieved and obtained by the structures specifically indicated in the specification and the accompanying drawings.

[0033] Those skilled in the art will appreciate that the objectives and advantages that can be achieved with the present invention are not limited to the above specific description, and the above and other objectives that can be achieved by the present invention will be more clearly understood from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of this application, and do not constitute a limitation of the present invention. The components in the drawings are not drawn to scale, but are only for illustrating the principles of the present invention. In order to facilitate the illustration and description of some parts of the present invention, the corresponding parts in the drawings may be enlarged, that is, they may become larger relative to other parts in the exemplary structure actually manufactured according to the present invention. In the drawings:

[0035] Figure 1 It is a schematic diagram of the structure of a track electronic device based on the track Hall effect in one embodiment of the present invention.

[0036] Figure 2 In one embodiment of the present invention, Ti0.7 Pt 0.3 (10) Schematic diagram of the structure of the / [Co(0.3) / Pt(0.8)]4 / SiO2(2) device.

[0037] Figure 3 It is a schematic diagram of the measurement of the track torque device in an embodiment of the present invention.

[0038] Figure 4 for Figure 2 The structure shown corresponds to R AHE -H and R AHE -J loop graph.

[0039] Figure 5 Schematic diagram of the Ti(10) / [Co(0.3) / Pt(0.8)]4 / SiO2(2) device structure as a comparative example.

[0040] Figure 6 for Figure 5 The structure shown corresponds to R AHE -H and R AHE -J loop graph.

[0041] Figure 7 In one embodiment of the present invention, Ti 0.7 G 0.3 (10) Schematic diagram of the structure of / [Co(0.3) / Pt(0.8)]4 / SiO2(2).

[0042] Figure 8 for Figure 7 The structure shown corresponds to R AHE -H and R AHE -J loop graph.

[0043] Fig. 9 In one embodiment of the present invention, Ti 0.7 MgO 0.3 (10) Schematic diagram of the structure of / [Co(0.3) / Pt(0.8)]4 / SiO2(2).

[0044] Fig.10 for Fig. 9 The structure shown corresponds to R AHE -H and R AHE -J loop graph.

[0045] Fig.11 The schematic diagram of the structure of an orbital electronic device containing synthetic antiferromagnetism (SAF) based on the orbital Hall effect in one embodiment of the present invention.

[0046] Fig.12 Schematic diagram of the structure of an artificially synthesized antiferromagnetic free layer in one embodiment of the present invention.

[0047] Fig.13 In one embodiment of the present invention, Ti 0.7 Pt 0.3 (10) Schematic diagram of the structure of / [Co(0.3) / Pt(0.8)]4 / Ru(0.6) / [Co(0.3) / Pt(0.8)]4 / SiO2(2).

[0048] Fig.14 FIG. 4 is a schematic diagram of the structure of a magnetic tunnel junction (MTJ) based on an artificial antiferromagnetic free layer in one embodiment of the present invention.

[0049] Fig.15 In one embodiment of the present invention, Ti 0.7 Pt 0.3 Schematic diagram of the structure of (10) / [Co(0.3) / Pt(0.8)]4 / Ru / [Co(0.3) / Pt(0.8)]4 / MgO(2) / CFB(1.3) / Ta(2) / SiO2(2). DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0051] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0052] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0053] It should also be noted that, unless otherwise specified, the term “connection” herein may refer not only to a direct connection but also to an indirect connection with an intermediate.

[0054] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0055] Currently, although theoretical calculations and experimental results have proved the existence of orbital torque OT, there is no research on optimizing the OT intensity by adjusting the orbital source material.

[0056] The inventors found in the process of implementing the present invention that for the track torque system, the track torque efficiency ξ OT Depends on η L-S ·θ OHE ,and Among them, η L-S represents the orbital-spin conversion coefficient of the ferromagnetic layer; θ OHE represents the orbital Hall angle generated by the orbital source; σ OHE represents the orbital Hall conductivity of the orbital source; σ xx represents the electronic conductivity of the orbital source, is the simplified Planck constant. Through the orbital torque efficiency ξ OT From the relationship, we can know that the track torque efficiency ξ OT The size of the ferromagnetic layer's orbital-spin conversion coefficient η L-S is closely related to, and depends on, the ratio of the orbital Hall conductivity of the orbital source to the electronic conductivity σ OHE / σ xx The inventors found that the electronic conductivity σ xx Closely related to impurity scattering, for the intrinsic OHE, the orbital Hall conductivity σ of the orbital source OHE In the clean limit, it is independent of scattering, and in the dirty limit, it decreases with increasing disorder. Therefore, in the clean limit, the intrinsic OHE dominates. In the dirty limit, the orbital Hall angle θ generated by the orbital source is OHE By reducing the electronic conductivity σ xx and increases until σ OHE / σ xx Therefore, in the embodiment of the present invention, while keeping the ferromagnetic layer unchanged, strong impurity scattering is introduced by introducing oxide or metal doping in the non-ferromagnetic layer as the orbital source, so that the electronic conductivity σ of the orbital source xx Reduce to increase the orbital Hall angle θ OHE At a larger orbital Hall angle θ OHE In the case of , the charge flow flowing into the orbital source layer can be converted into more orbital flow entering the ferromagnetic layer. Due to the larger orbital-spin conversion coefficient of the ferromagnetic layer, the orbital flow is converted into more spin flow. The spin flow generates more torque acting on the local magnetic moment of the ferromagnetic layer, thereby improving the orbital torque efficiency ξ OT , reducing the critical switching current density. That is, the present invention introduces strong impurity scattering by introducing oxide or metal doping into the non-ferromagnetic layer as the orbital source, so that the electronic conductivity σ of the orbital source xx Reduce to increase the orbital Hall angle θ OHE , thereby improving the orbital torque efficiency of the orbital torque system OT, reducing the critical flip current density. By increasing the track torque efficiency of the track torque system, the performance of track electronic devices can be effectively improved.

[0057] Figure 1 FIG. 1 is a schematic diagram of the structure of a track electronic device based on the track Hall effect in one embodiment of the present invention. Figure 1 As shown, the track electronic device comprises: a substrate 10; and a ferromagnetic / non-magnetic heterojunction structure 20 prepared on the substrate 10;

[0058] Among them, the ferromagnetic / non-magnetic heterojunction structure includes a ferromagnetic layer structure and a doped orbital Hall layer which is a non-ferromagnetic layer structure, the non-ferromagnetic layer is closer to the substrate, the ferromagnetic layer structure is located on the side of the non-ferromagnetic layer structure away from the substrate, and the ferromagnetic layer structure has perpendicular magnetic anisotropy; the doped orbital Hall layer is an orbital Hall channel layer obtained by doping a first metal or a two-dimensional transition metal sulfide (TMD) material as an orbital source with an oxide or a second metal, and the first metal is a 3d-5d metal material.

[0059] In some embodiments of the present invention, the substrate may be, for example, a Si / SiO2 substrate, an Al2O3 substrate or a MgO substrate, but the present invention is not limited thereto.

[0060] In some embodiments of the present invention, the ferromagnetic layer structure may be a ferromagnetic multi-film layer formed by multiple material layers, a ferromagnetic single film layer formed by multiple materials, or a two-dimensional ferromagnetic material layer. Among them, the ferromagnetic single film layer formed by multiple materials may be, for example, a CoFeB layer, a Co layer, a Ni layer, a CoNi alloy layer, a CoPt alloy layer, a CoPd alloy layer, a CoGd alloy layer, or a CoTb alloy layer; the two-dimensional ferromagnetic material layer may be, for example, MnBi2Te4, Fe3GeTe2, Cr2Ge2Te6, Fe5GeTe2, or Fe3GaTe2; the multi-film layer formed by multiple material layers may be, for example: a CoFeB / Gd / CoFeB multi-film layer, a CoFeB / Tb / CoFeB multi-film layer, a multi-film layer composed of multiple Co / Pt double film layers, a multi-film layer composed of multiple Co / Pd double film layers, a multi-film layer composed of multiple Co / Gd double film layers. , a multi-film layer composed of multiple Co / Tb double-film layers or a multi-film layer composed of multiple Co / Ni double-film layers, or a magnetic thin film material with similar properties; wherein the CoFeB / Gd / CoFeB multi-film layer is composed of a CoFeB layer, a Gd layer and a CoFeB layer; the CoFeB / Tb / CoFeB multi-film layer is composed of a CoFeB layer, a Tb layer and a CoFeB layer; the Co / Pt double-film layer is composed of a Co layer and a Pt layer; the Co / Pd double-film layer is composed of a Co layer and a Pd layer; the Co / Gd double-film layer is composed of a Co layer and a Gd layer; the Co / Tb double-film layer is composed of a Co layer and a Tb layer; the Co / Ni double-film layer is composed of a Co layer and a Ni layer. Specific examples of these ferromagnetic materials are disclosed in PCT International Application No. PCT / CN2023 / 140031, entitled "Orbital Electronics Devices with Orbital Hall Effect and Reverse Orbital Hall Effect and Methods for Efficiency Enhancement Thereof", which is also applicable to the present invention, and the contents of the PCT patent application are incorporated herein by reference as if fully set forth herein. In the subsequent examples, the ferromagnetic layer structure is a multi-layer consisting of four [Co / Pt] bilayers.

[0061] In some embodiments of the present invention, the oxide is magnesium oxide, titanium oxide, ruthenium oxide, gadolinium oxide or copper oxide; the second metal is one of the following metals: Gd, Pt, W, Au, Hf, Ta, Pd, Ir, Bi, Re, Ru or Rh; the first metal can be one of the following 3d-5d metal materials: Ti, Zr, Mn, Cr, Al, Ge, Ta, W; the two-dimensional transition metal sulfide (TMD) material is one of the following materials: WTe2, MoS2, WSe2, WS, TaTe2, MoTe2, NbSe2, PtTe2 or TaS2. As an example, in the case where the first metal is Ti, the non-ferromagnetic layer serving as the orbital Hall layer can be Ti x Pt 1-x 、Tix G 1-x 、Ti x MgO 1-x 、Ti x W 1-x 、Ti x Au 1-x In the case where the first metal is Zr, the non-ferromagnetic layer as the orbital Hall layer can be Zr x Pt 1-x 、Zr x G 1-x 、Zr x MgO 1-x 、Zr x W 1-x 、Zr x Au 1-x Alloy materials, wherein x is greater than 50%, that is, the first metal material is the main component, and the second metal or oxide is doped in the first metal material. However, the present invention is not limited to the listed materials, and can also be obtained by doping 3d-5d metal materials or two-dimensional transition metal sulfide (TMD) materials that are found to have orbital effects.

[0062] In some embodiments of the present invention, the rail electronics device may further include: a protective layer formed on the ferromagnetic / non-magnetic heterojunction structure, and the protective layer may also be omitted. The protective layer may include at least one of the following film layers: a magnesium oxide (MgO) / tungsten (W) layer, a tantalum (Ta) layer, a SiO2 layer, etc., but the present invention is not limited thereto.

[0063] In some embodiments of the present invention, the thickness of the non-ferromagnetic layer is preferably 2-20 nanometers, and the thickness of the ferromagnetic layer structure is preferably 1-20 nanometers.

[0064] By forming corresponding electrode layers on the basic structure of the electronic device as above, different types of track electronics devices can be formed.

[0065] As an example, the orbital electronic device based on the orbital Hall effect further includes: a top electrode and a lower electrode.

[0066] The top electrode (not shown) may be formed on the protection layer. In the case where the protection layer is omitted, the top electrode may also be directly formed on the ferromagnetic layer structure of the ferromagnetic / non-magnetic heterojunction.

[0067] A bottom electrode (not shown) may be formed to contact the orbital Hall channel layer for generating an in-plane current flowing through the orbital Hall channel layer. The bottom electrode and the top electrode may be used to generate a perpendicular current flowing through the ferromagnetic / non-magnetic heterojunction.

[0068] In some embodiments of the present invention, the non-ferromagnetic layer can be prepared by a magnetron sputtering process; when the ferromagnetic layer is a single film layer or a multi-film layer, each film layer is prepared by a magnetron sputtering process; when the ferromagnetic layer is a two-dimensional ferromagnetic material, the two-dimensional ferromagnetic material is prepared by magnetron sputtering, CVD / CVT or mechanical stripping and other processes.

[0069] The orbital electronic device of the present invention with the above structure can be used for spin-orbit moment electronic storage logic, orbital torque magnetic tunnel junction device and orbital Hall nano-oscillator device, etc.

[0070] Several examples of the structure, preparation, and track torque flip test results of rail electronics are listed below.

[0071] Example 1Ti 0.7 Pt 0.3 Basic structure of (10) / [Co(0.3) / Pt(0.8)]4 / SiO2(2) orbital electronic device

[0072] like Figure 2 As shown, the track electronic device provided in this embodiment includes the following film layers in sequence: a substrate (Si substrate or SiO2 substrate), a non-ferromagnetic layer Ti 0.7 Pt 0.3 (10), a ferromagnetic layer [Co(0.3) / Pt(0.8)]4 and a protective layer (SiO2 layer) on the ferromagnetic layer. The values ​​in the parentheses represent the thickness of each layer in nanometers. The subscripts in the brackets represent the number of Co / Pt double film layers, that is, the subscript 4 represents 4 Co / Pt double film layers. [Co(0.3) / Pt(0.8)]4 can be abbreviated as [Co / Pt]4. The thicknesses of the Co layer and the Pt layer in the Co / Pt double film layer are 0.3 nanometers and 0.8 nanometers, respectively. The thickness of the protective layer SiO2 is 2 nanometers. Figure 2 In the structure shown, the non-ferromagnetic layer Ti 0.7 Pt 0.3 As the orbital Hall layer, it is Ti doped with Pt, which can also be called Ti / Pt alloy; [Co / Pt]4 as a ferromagnetic layer structure, has good perpendicular magnetic anisotropy (PMA) and a large orbital-spin conversion coefficient and a large orbital-spin conversion coefficient, and the non-ferromagnetic layer structure Ti 0.7 Pt 0.3 The ferromagnetic layer structure [Co(0.3) / Pt(0.8)]4 forms a ferromagnetic / non-magnetic heterojunction structure. The silicon dioxide (SiO2) layer acts as a protective layer to protect the underlying film from oxidation.

[0073] The orbital electronics device based on the orbital Hall effect with the above structure in this embodiment is prepared by magnetron sputtering using the following process:

[0074] (1) An ultra-high vacuum multi-target sputtering system is used, and Ti, Co, Pt and SiO2 targets are installed on multiple sputtering target heads respectively;

[0075] (2) The Si / SiO2 substrate is placed on the sample holder, and appropriate process parameters are adjusted to form films on the substrate using magnetron sputtering.

[0076] When magnetron sputtering is used to form a film on a substrate, it is necessary to control the growth order of each layer. First, Ti is grown by sputtering a Ti target and a Pt target simultaneously. 0.7 Pt 0.3 The atomic ratio of Ti and Pt is controlled by controlling the sputtering power of the target. The process is to use Pt to dope the Ti film layer to form a Ti / Pt alloy; further, the Co and Pt films are grown in turn by sputtering the Co target and the Pt target, and the growth thickness of the Co film and the Pt film is controlled by controlling the sputtering time according to the sputtering rate to obtain a Co / Pt double film layer, and the Co and Pt films are repeatedly grown (i.e., the Co / Pt double film layer is repeatedly grown) to form four Co / Pt double film layers; then the SiO2 target is used to grow the SiO2 protective layer. Control Ti during the growth process 0.7 Pt 0.3 , Co, Pt and SiO2 films are 10, 0.3, 0.8 and 2 nm in thickness, respectively.

[0077] Exemplary process parameters during sample preparation may include: substrate temperature, sputtering atmosphere, sputtering power, etc. Exemplary process parameter conditions are: substrate temperature is room temperature; argon gas flow rate is 33 sccm; sputtering pressure is 3 mTorr; Ti growth 0.7 Pt 0.3 The sputtering powers of Ti and Pt in the thin film process are 100 and 36 watts respectively; the sputtering powers of Co and Pt in the process of growing [Co(0.3) / Pt(0.8)]4 multilayer film are 50 and 15 watts respectively, and the sputtering power of SiO2 in the process of growing the protective layer is 50 watts. The sputtering rates of Ti, Pt, Co, Pt and SiO2 are 0.194, 0.086, 0.237, 0.174 and 0.092 angstroms / second respectively. Here, the process parameters listed are only examples. The present invention is not limited to these specific parameters, but these parameters can be appropriately adjusted and changed. The thickness of each layer structure in the ferromagnetic layer and the composition ratio are adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy.

[0078] Track torque flip test:

[0079] The samples prepared as above were fabricated into Hall bars by standard photolithography and argon ion milling techniques. Figure 3 As shown, it is used to measure perpendicular magnetic anisotropy and critical switching current. Figure 3 The numbers 1, 2, 3, 4, 5, and 6 represent electrodes formed on the protective layer, and the number 7 represents Figure 2 The structure of the orbital electronics device in the circuit. A pulse current is passed along the longitudinal direction (electrode 3→4), and the anomalous Hall resistance R is measured in the transverse direction (electrode 1→5 or electrode 2→6). AHE Track torque test results are as follows: Figure 4 As shown. Among them, Figure 4 (a) indicates the prepared Figure 2 The structure shown in R AHE -H map, Figure 4 (b) indicates the prepared Figure 2 The structure shown in R AHE -J loop diagram. Among them, R AHE -H diagram shows abnormal Hall resistance R AHE As the external magnetic field changes, the AHE -H diagram can reflect the perpendicular magnetic anisotropy of the sample structure; R AHE -J diagram shows the abnormal Hall resistance R AHE As the applied current changes, the AHE -J diagram can reflect the critical reversal current density of the sample structure; by comparing R AHE -H and R AHE -J in R AHE The size of can reflect the extent to which the torque generated in the orbital source flips the magnetic moment of the ferromagnetic layer.

[0080] pass Figure 4 It can be seen that [Co / Pt]4 has good perpendicular magnetic anisotropy (PMA) and its critical switching current is very low, which is 1.6×10 7 A / cm 2 The test results prove that Figure 2 In the structure shown, the ferromagnetic layer has good perpendicular magnetic anisotropy, which also indicates that Ti 0.7 Pt 0.3 As an orbital Hall layer, the device has very high orbital torque efficiency.

[0081] In order to Figure 2 As a comparison, the present invention also uses a magnetron sputtering process to prepare a Ti(10) / [Co(0.3) / Pt(0.8)]4 / SiO2(2) track electronic device as a comparative example. Figure 5As shown, the track electronic device includes the following film layers in sequence: substrate (Si or SiO2), non-ferromagnetic layer Ti (10), ferromagnetic layer [Co (0.3) / Pt (0.8)] 4 and protective layer SiO2 (2). The values ​​in brackets represent the thickness of each film layer in nanometers. The thickness of the non-ferromagnetic layer Ti is 10 nanometers, the ferromagnetic layer [Co (0.3) / Pt (0.8)] 4 is a multi-layer film, in which the thicknesses of Co and Pt are 0.3 nanometers and 0.8 nanometers respectively, and the thickness of the protective layer SiO2 is 2 nanometers. 3d metal Ti is used as the track source. 3d metal Ti and the ferromagnetic layer form a ferromagnetic / non-magnetic heterojunction. Figure 2 Compared with the structure shown in FIG. 1 , the only difference is that the non-ferromagnetic layer is undoped Ti. Figure 2 The preparation process of the track electronic device structure shown is basically the same. The only difference is that when preparing the track source, instead of controlling the Ti target and the Pt target at the same time to achieve doping and generate Ti / Pt alloy, only the Ti target is controlled at a sputtering power of 100 watts and a sputtering rate of 0.194 angstroms / second to form a Ti film.

[0082] Figure 6 The following are the results of the track torque test for the comparative example. Figure 6 It can be seen that Ti / [Co / Pt]4 / SiO2(2) has good perpendicular magnetic anisotropy and its critical switching current is also very low, which is 2.0×10 7 A / cm 2 , which is comparable to the critical current for magnetic moment reversal of traditional heavy metals, indicating that Ti / [Co / Pt]4 / SiO2(2) has high orbital torque efficiency. However, the orbital torque efficiency of the comparative example is lower than Figure 2 The orbital torque efficiency of the orbital electronic device structure in the 0.7 Pt 0.3 As an orbital source, the orbital torque efficiency of the device is significantly improved, thereby making the critical switching current density lower than the current density of the device with Ti as the orbital source.

[0083] Example 2: Ti 0.7 G 0.3 (10) / [Co(0.3) / Pt(0.8)]4 / SiO2(2) orbital electronic devices

[0084] like Figure 7 As shown, the track electronic device provided in this embodiment includes the following film layers in sequence: substrate (Si or SiO2), non-ferromagnetic layer Ti 0.7 G 0.3(10), a ferromagnetic layer [Co(0.3) / Pt(0.8)]4 (can be abbreviated as [Co / Pt]4) and a protective layer (SiO2 layer) located on the ferromagnetic layer. The values ​​in the parentheses represent the thickness of each layer in nanometers. The subscript 4 in the brackets represents the number of Co / Pt double film layers. In this embodiment, Ti 0.7 G 0.3 The layer is used as the orbital Hall layer, which is Ti doped with Gd, also known as Ti / Gd alloy; [Co / Pt]4 is used as the ferromagnetic layer structure, which has good perpendicular magnetic anisotropy (PMA) and a large orbital-spin conversion coefficient. 0.7 G 0.3 and the ferromagnetic layer to form a ferromagnetic / non-magnetic heterojunction.

[0085] The orbital electronics device based on the orbital Hall effect with the above structure in this embodiment is prepared by magnetron sputtering using the following process:

[0086] (1) An ultra-high vacuum multi-target sputtering system is used, and Ti, Gd, Co, Pt and SiO2 targets are installed on multiple sputtering target heads respectively;

[0087] (2) The Si / SiO2 substrate is placed on the sample holder, and appropriate process parameters are adjusted to form films on the substrate using magnetron sputtering.

[0088] The growth order of each layer is controlled. First, Ti is grown by sputtering Ti and Gd targets simultaneously. 0.7 G 0.3 The atomic ratio of Ti and Gd is controlled by controlling the sputtering power. The process is to use metal Gd to dope the Ti film layer to form a Ti / Gd alloy. Further, the Co and Pt films are grown by sputtering Co targets and Pt targets in turn. The growth thickness of the Co and Pt films is controlled by controlling the sputtering time according to the sputtering rate, and the Co and Pt films are repeatedly grown to form four Co / Pt double film layers. Then, the SiO2 target is used to grow the SiO2 protective layer. Control Ti during the growth process 0.7 G 0.3 , Co, Pt and SiO2 films are 10, 0.3, 0.8 and 2 nm in thickness, respectively.

[0089] Exemplary process parameters in the sample preparation process include: substrate temperature is room temperature; argon flow rate is 33sccm; sputtering pressure is 3mTorr; sputtering powers of Ti, Gd, Co, Pt and SiO2 are 100, 11, 50, 15 and 50 watts, respectively, and sputtering rates are 0.194, 0.09, 0.237, 0.174 and 0.092 angstroms / second, respectively. The process parameters listed here are only examples. The present invention is not limited to these specific parameters, but these parameters can be appropriately adjusted and changed. The thickness of each layer structure in the ferromagnetic layer and the composition ratio are adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy.

[0090] Track torque flip test:

[0091] The samples were fabricated into Hall bars by standard photolithography and argon ion milling techniques. Figure 8 As shown. Figure 8 It can be seen that [Co / Pt]4 has good perpendicular magnetic anisotropy (PMA) and its critical switching current is very low, which is 1.3×10 7 A / cm 2 The test results also prove that the ferromagnetic layer has good perpendicular magnetic anisotropy, and also show that Ti 0.7 G 0.3 As an orbital source, the orbital torque efficiency of the device is greatly improved compared to the Ti orbital source, so that the critical reversal current density is lower than the current density of the device with Ti as the orbital source.

[0092] Example 3Ti 0.7 MgO 0.3 (10) / [Co(0.3) / Pt(0.8)]4 / SiO2(2) orbital electronic devices

[0093] like Fig. 9 As shown, the track electronic device provided in this embodiment includes the following film layers in sequence: substrate (Si or SiO2), non-ferromagnetic layer Ti 0.7 MgO 0.3 (10), a ferromagnetic layer [Co(0.3) / Pt(0.8)]4 (can be abbreviated as [Co / Pt]4) and a protective layer (SiO2 layer) located on the ferromagnetic layer. The values ​​in the parentheses represent the thickness of each layer in nanometers. The subscript 4 in the brackets represents the number of Co / Pt double film layers. In this embodiment, Ti 0.7 MgO 0.3 As the orbital source, it is Ti doped with MgO, which can also be called Ti / MgO alloy; [Co / Pt]4 as the ferromagnetic layer structure, it has good perpendicular magnetic anisotropy (PMA) and a large orbital-spin conversion coefficient, Ti 0.7 MgO0.3 and the ferromagnetic layer to form a ferromagnetic / non-magnetic heterojunction.

[0094] The orbital electronics device based on the orbital Hall effect with the above structure in this embodiment is prepared by magnetron sputtering using the following process:

[0095] (1) An ultra-high vacuum multi-target sputtering system is used, and Ti, MgO, Co, Pt and SiO2 targets are installed on multiple sputtering target heads respectively;

[0096] (2) The Si / SiO2 substrate is placed on the sample holder, and appropriate process parameters are adjusted to form films on the substrate using magnetron sputtering.

[0097] The growth order of each layer is controlled. First, Ti is grown by sputtering a Ti target and a MgO target simultaneously. 0.7 MgO 0.3 The atomic ratio of Ti and MgO is controlled by controlling the sputtering power. The process is to use the oxide MgO to dope the Ti film layer to form a Ti / MgO alloy; further, the Co and Pt films are grown by sputtering the Co target and the Pt target in turn. According to the sputtering rate, the growth thickness of the Co film and the Pt film is controlled by controlling the sputtering time, and the Co and Pt films are repeatedly grown to form four Co / Pt double film layers; then the SiO2 target is used to grow the SiO2 protective layer. Control the Ti during the growth process 0.7 MgO 0.3 , Co, Pt and SiO2 films are 10, 0.3, 0.8 and 2 nm in thickness, respectively.

[0098] Exemplary process parameters in the sample preparation process include: substrate temperature, sputtering atmosphere and sputtering power. For example, the substrate temperature is room temperature; the argon flow rate is 33sccm; the sputtering pressure is 3mTorr; the sputtering powers of Ti, MgO, Co, Pt and SiO2 are 100, 206, 50, 15 and 50 watts, respectively, and the sputtering rates are 0.194, 0.086, 0.237, 0.174 and 0.092 angstroms / second, respectively. The process parameters listed here are only examples. The present invention is not limited to these specific parameters, but these parameters can be appropriately adjusted and changed. The thickness of each layer structure in the ferromagnetic layer and the composition ratio are adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy.

[0099] Track torque flip test:

[0100] The samples were fabricated into Hall bars by standard photolithography and argon ion milling techniques. Fig.10 As shown. Fig.10It can be seen that [Co / Pt]4 has good perpendicular magnetic anisotropy (PMA) and its critical switching current is very low, which is 1.5×10 7 A / cm 2 The test results also prove that the ferromagnetic layer has good perpendicular magnetic anisotropy, and also show that Ti 0.7 MgO 0.3 As an orbital source, the orbital torque efficiency of the device is greatly improved compared to the Ti orbital source, so that the critical reversal current density is lower than the current density of the device with Ti as the orbital source.

[0101] In some embodiments of the present invention, the ferromagnetic layer structure in the ferromagnetic / non-magnetic heterojunction structure of the railtronics device is an artificial synthetic antiferromagnetic layer (Synthetic Antiferromagnets, SAF) with perpendicular magnetic anisotropy.

[0102] The synthetic antiferromagnetic structure refers to a structure in which two magnetic layers generate RKKY (Ruderman-Kittel-Kasuya-Yosida) interlayer exchange coupling through a non-magnetic layer (spacer layer), and the magnetic moments of the ferromagnetic layers are arranged in antiparallel under the interlayer exchange coupling. The synthetic antiferromagnetic structure has strong antiferromagnetic interlayer exchange coupling, so the synthetic antiferromagnetic structure has the advantages of small stray magnetic field and insensitivity to external magnetic field disturbance.

[0103] In some embodiments of the present invention, an artificial antiferromagnetic structure is applied to an orbital electronics device based on the orbital Hall effect. That is, in these embodiments, in addition to using the doped orbital source as the non-ferromagnetic layer in the ferromagnetic / non-magnetic heterojunction of the orbital electronics device, an artificial antiferromagnetic is also used as the ferromagnetic layer in the ferromagnetic / non-magnetic heterojunction of the orbital electronics device, thereby realizing orbital torque (OT) driven SAF. The inventors have found that using orbital flow to drive the magnetization reversal of the magnetic layer of the artificial antiferromagnetic structure can improve the orbital torque efficiency.

[0104] Example 4: Orbital electronic device containing synthetic antiferromagnetic (SAF) based on orbital Hall effect

[0105] Fig.11 FIG. 1 is a schematic diagram of the structure of a track electronic device containing SAF based on the track Hall effect in one embodiment of the present invention. Fig.11As shown, the orbital electronic device structure includes: a substrate 10, a ferromagnetic / non-magnetic heterojunction structure 20 and a protective layer 30, wherein the ferromagnetic / non-magnetic heterojunction structure 20 includes a non-ferromagnetic layer structure 21 as an orbital Hall layer and a ferromagnetic layer structure 22, wherein the non-ferromagnetic layer structure 21 is an orbital Hall channel layer obtained by doping a first metal (3d-5d metal material) or a two-dimensional transition metal sulfide (TMD) material suitable for being an orbital source with an oxide or a second metal, and the ferromagnetic layer structure 22 is an artificially synthesized antiferromagnetic layer or an artificially synthesized antiferromagnetic layer. Fig.12 As shown, the artificial synthetic antiferromagnetic layer 22 can be composed of a ferromagnetic layer 221, a non-magnetic layer 222 as a spacer layer, and a ferromagnetic layer 223, and the two magnetic layers are in an antiferromagnetic coupling state. The artificial synthetic ferromagnetic layer can also have the same structure, but under factors such as different thicknesses of the spacer layer, the two magnetic layers are in a ferromagnetic coupling state.

[0106] The ferromagnetic layers 221 and 223 may be selected from CoFeB, FePd, [Co / Ni] n 、[Co / Pd] n or [Co / Pt] n etc., where n refers to the number of times the multilayer is stacked, the thickness of the ferromagnetic layers 221 and 223 is 1 to 50 nanometers; the material of the spacer layer 222 may include one or more of Nb, Ta, Cr, Mo, W, Re, Ru, Os, Rh, Ir, Pt, Cu, Ag or Au, with a thickness of 0.1 nanometers to 10 nanometers.

[0107] Example 5: Ti 0.7 Pt 0.3 (10) / [Co(0.3) / Pt(0.8)]4 / Ru(0.6) / [Co(0.3) / Pt(0.8)]4 / SiO2(2) orbital electronic devices

[0108] like Fig.13 As shown, the track electronic device provided in this embodiment includes the following film layers in sequence: substrate (Si or SiO2), non-ferromagnetic layer Ti 0.7 Pt 0.3(10), artificial synthetic antiferromagnetic layer [Co(0.3) / Pt(0.8)]4 / Ru(0.6) / [Co(0.3) / Pt(0.8)]4 and protective layer, the values ​​in the parentheses represent the thickness of each layer in nanometers, and the subscript 4 in the square brackets represents the number of Co / Pt double film layers. The artificial synthetic antiferromagnetic layer [Co(0.3) / Pt(0.8)]4 / Ru(0.6) / [Co(0.3) / Pt(0.8)]4 as a ferromagnetic layer structure includes a ferromagnetic layer [Co(0.3) / Pt(0.8)]4, a non-magnetic layer Ru and a ferromagnetic layer [Co(0.3) / Pt(0.8)]4. The artificial synthetic antiferromagnetic layer has good perpendicular magnetic anisotropy (PMA) and a large orbital-spin conversion coefficient.

[0109] The orbital electronics device based on the orbital Hall effect with the above structure in this embodiment is prepared by magnetron sputtering using the following process:

[0110] (1) An ultra-high vacuum multi-target sputtering system is used, and Ti, Co, Pt, Ru and SiO2 targets are installed on multiple sputtering target heads respectively;

[0111] (2) The Si / SiO2 substrate is placed on the sample holder, and appropriate process parameters are adjusted to form films on the substrate using magnetron sputtering.

[0112] Control the growth order of each layer. First, Ti is grown by controlling the sputtering of Ti and Pt targets. 0.7 Pt 0.3 Thin film, by controlling the process parameters to control the atomic ratio of Ti and Pt, the process is to use Pt to dope the Ti film layer to form a Ti / Pt alloy; further, by controlling the sputtering of the Co target and the Pt target in turn to grow Co and Pt thin films, by controlling the growth rate and growth time to control the growth thickness of the Co film and the Pt film, and repeatedly grow Co and Pt thin films to form four Co / Pt double film layers; after forming four Co / Pt double film layers, further control the Ru target to grow a Ru film; after growing a Ru film of a predetermined thickness, repeatedly grow Co and Pt thin films to further form four Co / Pt double film layers. Then use a SiO2 target to grow a SiO2 protective layer. Control Ti during the growth process 0.7 Pt 0.3 , Co, Pt, Ru and SiO2 films are 10, 0.3, 0.8, 0.6 and 2 nm, respectively.

[0113] Exemplary process parameters during sample preparation may include: substrate temperature is room temperature; argon gas flow rate is 33 sccm; sputtering pressure is 3 mTorr; Ti growth 0.7 Pt 0.3During the film formation process, the sputtering powers of Ti and Pt are 100 and 36 watts respectively; during the growth of [Co(0.3) / Pt(0.8)]4 multilayer film, the sputtering powers of Co and Pt are 50 and 15 watts respectively; during the growth of Ru film, the sputtering power of Ru is 50 watts; during the growth of the protective layer, the sputtering power of SiO2 is 50 watts, and the sputtering rates of Ti, Pt, Co, Pt, Ru and SiO2 are 0.194, 0.086, 0.237, 0.174, 0.768 and 0.092 angstroms / second respectively; here, the listed process parameters are only examples, and the present invention is not limited to these specific parameters, but these parameters can be appropriately adjusted and changed. The thickness of each layer structure in the ferromagnetic layer and the composition ratio are adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy. In addition, although the thickness of the Ru layer in this embodiment is 0.6 nanometers, it is not limited thereto. As long as the thickness is between 0.6-1.3 nanometers, the two magnetic layers can be in an antiferromagnetic coupling state.

[0114] The results of the orbital torque reversal test show that the artificial antiferromagnetic layer [Co(0.3) / Pt(0.8)]4 / Ru / [Co(0.3) / Pt(0.8)]4 has good perpendicular magnetic anisotropy (PMA) and its critical reversal current is very low, and the device has very high orbital torque efficiency.

[0115] The inventors noticed that the orbital-spin conversion coefficient η L-S Perpendicular magnetic anisotropy (PMA) materials can improve orbital torque efficiency OT and turnover efficiency, but a low damping constant can further optimize ξ OT Since it is difficult for a single ferromagnetic layer to simultaneously satisfy the conditions of a large orbital-spin conversion coefficient and a low damping constant, in some embodiments of the present invention, it is preferred to use a layer having a large η L-S The PMA layer (first ferromagnetic layer, such as [Co / Pd] n or [Co / Pt] n etc.) and another layer with a smaller η L-S However, the artificial antiferromagnetic PMA layer (second ferromagnetic layer, such as CFB, etc.) with a lower damping constant (the damping constant is lower than the damping constant of the first ferromagnetic layer) can further optimize ξ OT and turnover efficiency.

[0116] In a further embodiment of the present invention, the orbital electronics device based on the orbital Hall effect using the artificial antiferromagnetic layer can also be applied to the magnetic tunnel junction (MTJ), and the MTJ can be further used as the basic structure (basic storage unit) of magnetic random access memory (MRAM) to form a new type of orbital torque magnetic random access memory (OT-MRAM). As a basic storage unit, MTJ has the advantages of non-volatility, high-speed reading and writing, good process compatibility, and unlimited erasing and writing. Therefore, the new type of magnetic random access memory (MRAM) with MTJ as the basic structure has become the research focus of the new type of memory. The magnetic tunnel junction MTJ includes a sandwich structure consisting of two magnetic metal layers and an ultra-thin insulating layer in the middle (called an intermediate layer or pinned layer), one of which is a ferromagnetic layer called a reference layer or a pinned layer, and its magnetization is fixed along the easy magnetization axis; the other ferromagnetic layer is called a free layer or a magnetic free layer, and its magnetization has two stable orientations, which are parallel or anti-parallel to the reference layer, respectively, which will put the magnetic tunnel junction in a low resistance state or a high resistance state, and this phenomenon is called the tunneling magnetoresistance effect. The intermediate layer is a non-magnetic barrier layer.

[0117] In the embodiment of the present invention, Fig.14 As shown, the MTJ type orbital electronics device formed based on the artificial synthetic antiferromagnetic layer structure includes the following structure: substrate 10, ferromagnetic / non-magnetic heterojunction structure 20, non-magnetic barrier layer 40, fixed layer 50 and protective layer 30, wherein the ferromagnetic / non-magnetic heterojunction structure 20 includes a non-ferromagnetic layer structure 21 and a ferromagnetic layer structure 22, wherein the non-ferromagnetic layer structure 21 is a doped orbital Hall layer obtained by doping a first metal (3d-5d metal material) or a two-dimensional transition metal sulfide (TMD) material with an oxide or a second metal as an orbital source, and the doped orbital Hall layer is used as a doped orbital source; the ferromagnetic layer structure 22 is a free layer, which can be an artificial synthetic antiferromagnetic layer. Wherein, as Fig.12As shown, the artificial synthetic antiferromagnetic layer 22 can be composed of a ferromagnetic layer 221, a non-magnetic layer 222 and a ferromagnetic layer 223. In an embodiment of the present invention, the artificial synthetic antiferromagnetic layer 22 serves as a free layer, and the free layer 22, the non-magnetic barrier layer 40 and the fixed layer 50 form an MTJ structure, that is, the embodiment of the present invention uses the orbital flow to regulate the artificial synthetic antiferromagnetic structure from the antiferromagnetic state to the ferromagnetic state, so that it becomes the free layer of the MTJ, combined with the relative orientation of the magnetic moment of the free layer and the magnetic moment of the fixed layer, it is used in MRAM to achieve high-speed data writing. In an embodiment of the present invention, the heterojunction formed by the doped orbital Hall channel layer and the artificial synthetic antiferromagnetic layer can achieve high orbital torque efficiency, thereby reducing the current loss during data writing, and the excellent PMA can increase the storage unit density. In an alternative embodiment of the present invention, the free layer can also be a ferromagnetic layer (FM) or an artificial synthetic ferromagnetic layer.

[0118] In one embodiment of the present invention, the barrier layer 40 may be one of MgO, Al2O3, NiO or SiC, and the fixed layer is made of ferromagnetic or ferrimagnetic metal and its alloy, and as an example, may be selected from one or more of NiFe, FePd, FePt, CoPd, CoPt, CoFe (i.e., CoFeB), CoFeB / Gd / CoFeB and CoFeB / Tb / CoFeB films. The material of the protective layer is also the same as that of other embodiments.

[0119] The MTJ based on an artificial synthetic antiferromagnetic free layer for OT-MRAM data writing provided by the embodiment of the present invention can realize efficient data writing and reduce energy consumption.

[0120] Fig.15 The Ti in one embodiment of the present invention is shown. 0.7 Pt 0.3 (10) / [Co(0.3) / Pt(0.8)]4 / Ru / [Co(0.3) / Pt(0.8)]4 / MgO(2) / CFB(1.3) / Ta(2) / SiO2(2) Fig.15 As shown, the SAF-based MTJ type track electronic device provided in this embodiment includes the following film layers in sequence: a substrate (Si or SiO2), a non-ferromagnetic layer doped track Hall layer Ti 0.7 Pt 0.3 (10), synthetic antiferromagnetic layer [Co(0.3) / Pt(0.8)]4 / Ru / [Co(0.3) / Pt(0.8)]4, non-magnetic barrier layer MgO(2), fixed layer CFB(1.3) / Ta(2) and protective layer SiO2(2), the values ​​in parentheses represent the thickness of each layer in nanometers, and the subscript 4 in the brackets represents the number of Co / Pt double film layers. Ti 0.7 Pt 0.3(10) as the orbital Hall layer, the artificial antiferromagnetic layer [Co(0.3) / Pt(0.8)]4 / Ru / [Co(0.3) / Pt(0.8)]4 as the magnetic free layer of the MTJ, and the artificial antiferromagnetic layer has good perpendicular magnetic anisotropy (PMA). MgO(2) is used as the non-magnetic barrier layer; CFB(1.3) / Ta(2) is used as the fixed layer. In an alternative embodiment of the present invention, the free layer can also be replaced by a ferromagnetic layer (FM) or an artificial ferromagnetic layer by the artificial antiferromagnetic layer.

[0121] The orbital electronics device based on the orbital Hall effect with the above structure in this embodiment is prepared by magnetron sputtering using the following process:

[0122] (1) An ultra-high vacuum multi-target sputtering system is used, and Ti, Co, Pt, Ru, MgO, CoFeB, Ta and SiO2 targets are installed on multiple sputtering target heads respectively;

[0123] (2) The Si / SiO2 substrate is placed on the sample holder, and appropriate process parameters are adjusted to form films on the substrate using magnetron sputtering.

[0124] Control the growth order of each layer. First, Ti is grown by controlling the sputtering of Ti and Pt targets. 0.7 Pt 0.3 Thin film, the atomic ratio of Ti and Pt is controlled by controlling the process parameters. The process is to use Pt to dope the Ti film layer to form a Ti / Pt alloy; further, the Co and Pt thin films are grown by controlling the sputtering of the Co target and the Pt target in turn, and the growth thickness of the Co film and the Pt film is controlled by controlling the growth rate and growth time, and the Co and Pt thin films are repeatedly grown to form four Co / Pt double film layers; after the four Co / Pt double film layers are formed, the Ru target is further controlled to grow a Ru film; after the Ru film of a predetermined thickness is grown, the Co and Pt thin films are repeatedly grown to further form four Co / Pt double film layers. Then, MgO target, CFB target, Ta target and SiO2 target are used to grow MgO film, CFB film, Ta film and SiO2 film as a protective layer respectively. Control Ti during the growth process 0.7 Pt 0.3 , Co, Pt, Ru, MgO, CFB, Ta, and SiO2 films have thicknesses of 10, 0.3, 0.8, 0.6, 2, 1.3, 2, and 2 nm, respectively.

[0125] Exemplary process parameters during sample preparation may include: substrate temperature is room temperature; argon gas flow rate is 33 sccm; sputtering pressure is 3 mTorr; Ti growth 0.7 Pt 0.3The sputtering powers of Ti and Pt during the growth of thin films were 100 and 36 W, respectively. The sputtering powers of Co and Pt during the growth of [Co(0.3) / Pt(0.8)]4 multilayer films were 50 and 15 W, respectively. The sputtering power of Ru during the growth of Ru films was 50 W. The sputtering power of Ta during the growth of Ta films was 50 W. The sputtering power of CFB during the growth of CFB films was 50 W. The sputtering power of MgO, CFB, Ta and SiO2 films as protective layers was 50 W. The sputtering powers of B, Ta, and SiO2 are 150 W, 50 W, 50 W, and 50 W, respectively, and the sputtering rates of Ti, Pt, Co, Pt, Ru, MgO, CFB, Ta, and SiO2 are 0.194, 0.086, 0.237, 0.174, 0.768, 0.055, 0.162, 0.331, and 0.092 angstroms per second, respectively; the process parameters listed here are only examples, and the present invention is not limited to these specific parameters, but these parameters can be appropriately adjusted and changed. The thickness of each layer structure and the composition ratio in the ferromagnetic layer are adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy. In addition, although the thickness of the Ru layer in this embodiment is 0.6 nanometers, it is not limited thereto. As long as its thickness is between 0.6-1.3 nanometers, the two magnetic layers can be in an antiferromagnetic coupling state.

[0126] The results of the orbital torque reversal test also show that the MTJ has good perpendicular magnetic anisotropy (PMA) and its critical reversal current is very low, and the device has very high orbital torque efficiency.

[0127] In the above embodiments of the present invention, the doping ratio of the light metal (first metal) and other metals (second metal) or oxides in the non-ferromagnetic layer is only an example, and the present invention is not limited thereto. Preferably, the atomic ratio of the first metal is greater than 50%.

[0128] In addition, in the above embodiments of the present invention, the thickness of each film layer and the number of layers of the multi-film layer are only examples, and are not limited thereto in practical applications, but may be varied within an appropriate range.

[0129] The orbital electronics device based on the orbital Hall effect and the preparation method thereof provided in the embodiments of the present invention can enhance the orbital torque efficiency and reduce the critical reversal current density by doping the light metal used as the orbital source with oxides or metal molecules.

[0130] It should be clear that the present invention is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present invention.

[0131] In the present invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with features of other embodiments or replace features of other embodiments.

[0132] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A track electronics device based on track Hall effect, characterized in that: The track electronics include: a substrate; and A ferromagnetic / non-magnetic heterojunction structure prepared on a substrate, wherein the ferromagnetic / non-magnetic heterojunction structure comprises a ferromagnetic layer structure and a non-ferromagnetic layer structure as a track Hall layer, wherein the ferromagnetic layer structure is located on a side of the non-ferromagnetic layer structure away from the substrate, and the ferromagnetic layer structure has perpendicular magnetic anisotropy; The orbital Hall layer is a doped orbital Hall layer formed by doping oxide or a second metal into a first metal or a two-dimensional transition metal sulfide material as an orbital source, and the first metal is a 3d-5d metal material.

2. The rail electronics device according to claim 1, characterized in that: The track electronics device also includes: A protective layer is formed on the ferromagnetic / non-magnetic heterojunction structure.

3. The rail electronics device according to claim 1, characterized in that: The oxide is magnesium oxide, titanium oxide, ruthenium oxide, gadolinium oxide or copper oxide; the second metal is selected from one of the following metals: Gd, Pt, W, Au, Hf, Ta, Pd, Ir, Bi, Re, Ru or Rh; The first metal is selected from one of the following 3d-5d metal materials: Ti, Zr, Mn, Cr, Al, Ge, Ta, W; the two-dimensional transition metal sulfide material is one of the following materials: WTe2, MoS2, WSe2, WS, TaTe2, MoTe2, NbSe2, PtTe2 or TaS2.

4. The rail electronics device according to claim 1, characterized in that: The ferromagnetic layer structure includes a ferromagnetic multi-film layer formed by multiple material layers, a ferromagnetic single film layer formed by multiple materials, or a two-dimensional ferromagnetic material layer.

5. The rail electronics device according to claim 4, characterized in that: The ferromagnetic single film layer formed by the plurality of materials is a CoFeB layer, a Co layer, a Ni layer, a CoNi alloy layer, a CoPt alloy layer, a CoGd alloy layer, a CoPd alloy layer or a CoTb alloy layer; The multi-film layer formed by the multiple material layers is: a CoFeB / Gd / CoFeB multi-film layer, a CoFeB / Tb / CoFeB multi-film layer, a multi-film layer composed of multiple Co / Pt double-film layers, a multi-film layer composed of multiple Co / Pd double-film layers, a multi-film layer composed of multiple Co / Gd double-film layers, a multi-film layer composed of multiple Co / Tb double-film layers, or a multi-film layer composed of multiple Co / Ni double-film layers; or The two-dimensional ferromagnetic material is MnBi2Te4, Fe3GeTe2, Cr2Ge2Te6, Fe5GeTe2 or Fe3GaTe2.

6. The rail electronics device according to claim 1, characterized in that: The ferromagnetic layer structure is an artificial antiferromagnetic layer or an artificial ferromagnetic layer; The artificial antiferromagnetic layer or artificial ferromagnetic layer comprises a first ferromagnetic layer, a second ferromagnetic layer and a spacer layer located between the first ferromagnetic layer and the second ferromagnetic layer, and the spacer layer is a non-magnetic layer.

7. The rail electronics device according to claim 6, characterized in that: The first ferromagnetic layer is a ferromagnetic layer having a larger orbit-spin conversion coefficient, and the second ferromagnetic layer is a ferromagnetic layer having a smaller orbit-spin conversion coefficient and a lower damping constant than the first ferromagnetic layer.

8. The rail electronics device according to claim 6, characterized in that: The first ferromagnetic layer in the artificial antiferromagnetic layer is one of the following single-layer ferromagnetic materials or multi-layer ferromagnetic materials: CoFeB, FePd, [Co / Ni] n 、[Co / Pd] n or [Co / Pt] n The second ferromagnetic layer is selected from CoFeB, FePd, [Co / Ni] n 、[Co / Pd] n or [Co / Pt] n One of the following, wherein n represents the number of times the [Co / Pd] double film layer, the [Co / Pt] double film layer and the [Co / Ni] double film layer are repeatedly stacked, and n is greater than 1.

9. The rail electronics device according to claim 6, characterized in that: The spacer layer includes one or more of Nb, Ta, Cr, Mo, W, Re, Ru, Os, Rh, Ir, Pt, Cu, Ag or Au.

10. The rail electronics device according to any one of claims 1 to 7, characterized in that: The ferromagnetic layer structure is used as a magnetic free layer; The track electronics device also includes: a nonmagnetic barrier layer formed on a side of the magnetic free layer away from the substrate; and A fixed layer formed on a side of the non-magnetic barrier layer away from the magnetic free layer, wherein the fixed layer is a ferromagnetic layer; The magnetic free layer, the nonmagnetic barrier layer and the fixed layer form a magnetic tunnel junction.

11. The rail electronics device according to claim 10, characterized in that: The material of the non-magnetic barrier layer is selected from MgO, Al2O3, NiO, TiO x , BN, or one of the two-dimensional semiconductors WSe2; The fixed layer is selected from one or more of NiFe, FePd, FePt, CoPd, CoPt, CoFeB, CoFeB / Gd / CoFeB, CoFeB / Tb / CoFeB films.

12. A magnetic random access memory, characterized in that: The magnetic random access memory comprises a basic storage unit based on a magnetic tunnel junction, and the basic storage unit comprises: substrate; A doped orbital Hall layer prepared on a substrate; A magnetic free layer, which is located on a side of the doped orbital Hall layer away from the substrate, and the magnetic free layer has perpendicular magnetic anisotropy; a nonmagnetic barrier layer formed on a side of the magnetic free layer away from the substrate; and A fixed layer formed on a side of the non-magnetic barrier layer away from the magnetic free layer, wherein the fixed layer is a ferromagnetic layer; The doped orbital Hall layer is formed by doping oxide or a second metal into a first metal or a two-dimensional transition metal sulfide (TMD) material, and the first metal is a 3d-5d metal material; the magnetic free layer, the nonmagnetic barrier layer and the fixed layer form a magnetic tunnel junction.

13. The magnetic random access memory according to claim 12, characterized in that: The magnetic free layer is an artificial antiferromagnetic layer or an artificial ferromagnetic layer; The artificial antiferromagnetic layer or artificial ferromagnetic layer comprises a first ferromagnetic layer, a second ferromagnetic layer and a spacer layer located between the first ferromagnetic layer and the second ferromagnetic layer, and the spacer layer is a non-magnetic layer.

14. A method for preparing an orbital electronics device based on orbital Hall effect, characterized in that: The method comprises the following steps: A doped orbital Hall layer is grown on a substrate as a non-ferromagnetic layer structure by magnetron sputtering, wherein the doped orbital Hall layer is obtained by doping an oxide or a second metal in a first metal or a two-dimensional transition metal sulfide (TMD) material as an orbital source by magnetron sputtering, wherein the first metal is a 3d-5d metal material; and Growing a ferromagnetic layer structure on the non-ferromagnetic layer structure by magnetron sputtering, wherein the thickness and composition ratio of each layer structure in the ferromagnetic layer of the ferromagnetic layer structure are adjusted so that the ferromagnetic layer as a whole has good perpendicular magnetic anisotropy; The ferromagnetic layer structure and the non-ferromagnetic layer structure serving as the track Hall layer form a ferromagnetic / non-magnetic heterojunction structure.

15. The method according to claim 14, characterized in that The method further comprises: A protective layer is formed on the ferromagnetic / non-magnetic heterojunction structure by magnetron sputtering.

16. The method according to claim 14, characterized in that The ferromagnetic layer structure is an artificial synthetic antiferromagnetic layer or an artificial synthetic ferromagnetic layer, and the artificial synthetic antiferromagnetic layer or the artificial synthetic ferromagnetic layer includes a first ferromagnetic layer, a second ferromagnetic layer and a spacer layer located between the first ferromagnetic layer and the second ferromagnetic layer, and the spacer layer is a non-magnetic layer; In the case where the ferromagnetic layer structure includes a plurality of film layers, each film layer is formed by magnetron sputtering.

17. The method according to any one of claims 14 to 16, characterized in that: The ferromagnetic layer structure is used as a magnetic free layer; the method further comprises: forming a non-magnetic barrier layer on a surface of the magnetic free layer away from the substrate by magnetron sputtering; and forming a fixed layer on the side of the non-magnetic barrier layer away from the magnetic free layer by magnetron sputtering, wherein the fixed layer is a ferromagnetic layer; The magnetic free layer, the nonmagnetic barrier layer, and the pinned layer form a magnetic tunnel junction.

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