Room-temperature all-electrically controlled magnetic storage unit and memory based on two-dimensional heterojunction

Abstract

Provided is a room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction, which includes a competing spin current alloy layer, a room-temperature van der Waals magnetic free layer, a van der Waals spacer layer, and a room-temperature van der Waals magnetic fixed layer that are stacked from bottom to top; the competing spin current alloy layer is composed of an alloy material with opposite spin Hall angles or an alloy composed of transition metal elements with opposite spin Hall angles, and realizes pure electrically controlled magnetic flipping of the room-temperature van der Waals magnetic free layer without external magnetic field assistance through the extra out-of-plane polarized spin current generated by the competing spin current effect; the room-temperature van der Waals magnetic free layer is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy; the van der Waals spacer layer is composed of a two-dimensional van der Waals material with a semiconductor or insulator band gap and resistivity; the room-temperature van der Waals magnetic fixed layer is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is fixed and does not change with the polarity of the electrical signal. Also provided is a magnetic memory.

Description

Technical Field

[0001] The present disclosure relates to the field of microelectronics technology, and particularly to a room-temperature all-electrically controlled magnetic storage unit and memory based on a two-dimensional heterojunction. Background Art

[0002] Compared with the spin-transfer torque magnetic random access memory (STT-MRAM), the spin-orbit torque magnetic random access memory (SOT-MRAM) has a higher writing speed and lower power consumption, and has a good application prospect, and is considered as the main writing method for the next-generation MRAM.

[0003] A typical magnetic tunnel junction (MTJ) device generally has a sandwich structure, that is, it is composed of upper and lower magnetic electrodes sandwiching a middle non-magnetic semiconductor or insulator barrier layer. Magnetic tunnel junction devices with a large tunneling magnetoresistance (TMR) are widely used in spintronics fields such as magnetic sensing, non-volatile magnetic random access memory, and programmable spin logic devices. Traditional magnetic tunnel junctions are usually composed of magnetic metal materials (such as Fe, Co, Ni, CoFeB and their alloys) bonded by three-dimensional covalent bonds and non-magnetic wide-bandgap oxides (such as Al 2 O 3 , MgO). At present, the development of magnetic tunnel junction devices based on traditional three-dimensional materials is restricted by the performance factors of the materials themselves. When forming a heterojunction between different three-dimensional materials, problems such as lattice matching, interdiffusion of atoms between interfaces, poor perpendicular magnetic anisotropy of magnetic electrodes, or pinhole effects in the middle barrier layer seriously limit the development of magnetic tunnel junctions based on traditional three-dimensional materials. Therefore, magnetic tunnel junction devices urgently need to find new materials with high interface quality. In addition, existing magnetic tunnel junction devices based on two-dimensional magnetic materials do not have tunneling magnetoresistance at room temperature and have poor temperature stability, which cannot meet the application requirements. Summary of the Invention

[0004] (1) Technical Problems to be Solved

[0005] Based on the above problems, the present disclosure provides a room-temperature all-electrically controlled magnetic storage unit and memory based on a two-dimensional heterojunction, so as to alleviate problems such as interface lattice mismatch, low interface flatness, or interdiffusion of atoms between interfaces in magnetic tunnel junction devices based on bulk materials in the prior art, as well as technical problems such as the lack of tunneling magnetoresistance at room temperature and poor temperature stability in magnetic tunnel junctions based on existing two-dimensional materials.

[0006] (2) Technical Solutions

[0007] One aspect of the present disclosure provides a room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction, including: a competing spin current alloy layer, a room-temperature van der Waals magnetic free layer, a van der Waals spacer layer, and a room-temperature van der Waals magnetic fixed layer, which are stacked from bottom to top; wherein, the competing spin current alloy layer is composed of alloy materials with opposite spin Hall angles or alloys composed of transition metal elements with opposite spin Hall angles, and realizes pure electrically controlled magnetic flipping of the room-temperature van der Waals magnetic free layer without external magnetic field assistance through the extra out-of-plane polarized spin current generated by the competing spin current effect; the room-temperature van der Waals magnetic free layer is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is controlled by the polarity of the electrical signal input to the competing spin current alloy layer; the van der Waals spacer layer is composed of a two-dimensional van der Waals material with a semiconductor bandgap and resistivity, or a two-dimensional van der Waals material with an insulator bandgap and resistivity; and the room-temperature van der Waals magnetic fixed layer is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is fixed and does not change with the change of the polarity of the electrical signal input to the competing spin current alloy layer.

[0008] According to an embodiment of the present disclosure, the magnetic storage unit further includes a van der Waals pinning layer, the van der Waals pinning layer is disposed on the room-temperature van der Waals magnetic fixed layer, and the van der Waals pinning layer is composed of a room-temperature two-dimensional antiferromagnetic material.

[0009] According to an embodiment of the present disclosure, when the competing spin current alloy layer is composed of alloy materials with opposite spin Hall angles, the alloy materials with opposite spin Hall angles are an alloy X-Y composed of heavy metal elements and rare earth elements, wherein X is selected from Hf, Pt, Ta or W; Y is selected from Gd, Tb, Dy or Ho; when the competing spin current alloy layer is composed of an alloy A-B composed of transition metal elements with opposite spin Hall angles, the transition metal A with a positive spin Hall angle is selected from Hf, Pt, Pd, Rh or Ru; the transition metal B with a negative spin Hall angle is selected from Ta, W, Nb or Mo.

[0010] According to an embodiment of the present disclosure, the preparation materials of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer include two-dimensional Fe 3 GaTe 2 。

[0011] According to an embodiment of the present disclosure, the preparation materials of the van der Waals spacer layer are selected from two-dimensional hBN, two-dimensional GaSe, two-dimensional InSe, two-dimensional WSe 2 、two-dimensional WS 2 、two-dimensional MoTe 2 、two-dimensional MoSe 2 。

[0012] According to an embodiment of the present disclosure, the preparation materials of the van der Waals pinning layer include two-dimensional TaCoTe2 。

[0013] According to the embodiments of the present disclosure, the thicknesses of the room-temperature van der Waals magnetic free layer, the van der Waals spacer layer, the room-temperature van der Waals magnetic fixed layer, or the van der Waals pinning layer are respectively between a single atomic layer thickness and fifty nanometers.

[0014] According to the embodiments of the present disclosure, the resistance state of the tunnel junction composed of the room-temperature van der Waals magnetic free layer, the van der Waals spacer layer, and the room-temperature van der Waals magnetic fixed layer is determined by the relative magnetization states of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer: when the magnetic moment directions of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer are the same, the tunnel junction is in a low-resistance state; when the magnetic moment directions of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer are opposite, the tunnel junction is in a high-resistance state.

[0015] On the other hand, the present disclosure provides a room-temperature all-electrically controlled magnetic memory based on a two-dimensional heterojunction, including: the room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction as described above; a metal top electrode disposed above the magnetic storage unit; wherein, the metal top electrode serves as the data reading end of the room-temperature all-electrically controlled magnetic memory; and the competing spin current alloy layer in the magnetic storage unit serves as the data writing end of the magnetic memory.

[0016] According to the embodiments of the present disclosure, the magnetic memory further includes: a metal bottom electrode disposed below the competing spin current alloy layer in the magnetic storage unit, and the metal bottom electrode serves as the data writing end of the magnetic memory.

[0017] (III) Advantageous Effects

[0018] It can be seen from the above technical solutions that the room-temperature all-electrically controlled magnetic storage unit and memory based on a two-dimensional heterojunction of the present disclosure have at least one or a part of the following advantageous effects:

[0019] (1) In the room-temperature all-electrically controlled magnetic storage unit, except for the competing spin current alloy layer, each layer is made of two-dimensional materials. Different from bulk materials, two-dimensional materials can be prepared as thin as a single atomic layer thickness, so they have higher compactness than bulk materials;

[0020] (2) High-quality tunnel junction devices are prepared using two-dimensional material heterojunctions. Different from bulk materials, in two-dimensional layered van der Waals materials, the layers are tightly bonded by covalent bonds within the layer, and only weakly bonded by van der Waals forces between layers. Therefore, there are no dangling bonds on the surface of two-dimensional layered materials. We can arbitrarily stack different two-dimensional van der Waals materials to form heterojunctions without considering problems such as lattice matching, interdiffusion of atoms at the interface, poor perpendicular magnetic anisotropy of magnetic electrodes, or pinhole effects in the intermediate barrier layer, and it is very easy to prepare tunnel junction devices with high interface quality;

[0021] (3) By taking advantage of the characteristic that the spin polarization direction remains unchanged when electron tunneling passes through the van der Waals spacer layer with a semiconductor or insulator bandgap, the magnetoresistance signal is enhanced, achieving a maximum TMR of ≥ 80% at room temperature, meeting the application requirements of magnetic memories. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] To more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0023] FIG. 1(a) is a schematic structural diagram of a room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction according to an embodiment of the present disclosure;

[0024] FIG. 1(b) is a schematic structural diagram of a room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction according to another embodiment of the present disclosure; among them, the magnetic storage unit shown in FIG. 1(b) is provided with a van der Waals pinning layer;

[0025] FIG. 2(a) is a schematic structural diagram of a room-temperature all-electrically controlled magnetic memory based on a two-dimensional heterojunction according to an embodiment of the present disclosure; among them, the magnetic memory shown in FIG. 2(a) is only provided with a metal top electrode;

[0026] FIG. 2(b) is a schematic structural diagram of a room-temperature all-electrically controlled magnetic memory based on a two-dimensional heterojunction according to another embodiment of the present disclosure; the magnetic memory shown in FIG. 2(b) is provided with both a metal top electrode and a metal bottom electrode;

[0027] Figure 3 FIG. is a schematic diagram of the test results of the TMR of the room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction according to the embodiment of the present disclosure at room temperature (300K).

[0028]

MAIN ELEMENT SYMBOL DESCRIPTIONS IN THE DRAWINGS OF THE EMBODIMENTS OF THE PRESENT DISCLOSURE

[0029] 100 - Room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction; 101 - Competing spin current alloy layer; 102 - Room-temperature van der Waals magnetic free layer; 103 - Van der Waals spacer layer; 104 - Room-temperature van der Waals magnetic fixed layer; 105 - Van der Waals pinning layer; 201 - Metal top electrode; 202 - Metal bottom electrode. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The present disclosure provides a room-temperature all-electrically controlled magnetic storage unit and a memory based on a two-dimensional heterojunction, which can operate normally at room temperature. By utilizing the characteristic that the spin polarization direction remains unchanged when electrons tunnel through a van der Waals spacer layer with a semiconductor or insulator bandgap, the magnetoresistance signal is enhanced, achieving a tunneling magnetoresistance of over 80% at room temperature, and solving the problems that the magnetic tunnel junction based on two-dimensional materials does not have tunneling magnetoresistance at room temperature and has poor temperature stability.

[0031] To make the objectives, technical solutions, and advantages of the present disclosure clearer and more understandable, the following further elaborates on the present disclosure in detail with reference to specific embodiments and the accompanying drawings.

[0032] In an embodiment of the present disclosure, a room-temperature all-electrically controlled magnetic storage unit based on a two-dimensional heterojunction is provided. As shown in FIG. 1(a), the room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction includes: a competing spin current alloy layer 101, a room-temperature van der Waals magnetic free layer 102, a van der Waals spacer layer 103, and a room-temperature van der Waals magnetic fixed layer 104, which are stacked from bottom to top;

[0033] Among them, the competing spin current alloy layer 101 is composed of an alloy material with opposite spin Hall angles or an alloy composed of transition metal elements with opposite spin Hall angles, and realizes pure electrically controlled magnetic flipping of the room-temperature van der Waals magnetic free layer without external magnetic field assistance through the additional out-of-plane polarized spin current generated by the competing spin current effect;

[0034] The room-temperature van der Waals magnetic free layer 102 is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is controlled by the polarity of the electrical signal input to the competing spin current alloy layer;

[0035] The van der Waals spacer layer 103 is composed of a two-dimensional van der Waals material with a semiconductor bandgap and resistivity, or is composed of a two-dimensional van der Waals material with an insulator bandgap and resistivity; and

[0036] The room-temperature van der Waals magnetic fixed layer 104 is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is fixed and does not change with the change of the polarity of the electrical signal input to the competing spin current alloy layer.

[0037] According to an embodiment of the present disclosure, the competing spin current alloy layer 101 is composed of alloy materials with opposite spin Hall angles or alloys composed of transition metal elements with opposite spin Hall angles. The alloy materials with opposite spin Hall angles include an alloy X-Y composed of heavy metal elements and rare earth elements, where X is selected from Pt, Ta, or W, and Y is selected from Gd, Tb, Dy, or Ho. In the alloy A-B composed of transition metal elements with opposite spin Hall angles that makes up the competing spin current alloy layer 101, the transition metal A with a positive spin Hall angle is selected from Pt, Pd, Rh, or Ru, and the transition metal B with a negative spin Hall angle is selected from Hf, Ta, W, Nb, or Mo. As needed, the competing spin current alloy layer 101 is a homogeneous alloy composed of different elements with precisely controlled compositions, such as A 1-x B x etc., or an alloy with a vertical composition gradient, such as A 1-x B x / A 1-x-Δ1 B x+Δ1 / ... / A 1-x-Δn B x+Δn . Where x is the proportion of the B metal element in the alloy, and Δ1,..., Δn are the changes in the proportion of the B metal element in the alloy between adjacent layers.

[0038] According to an embodiment of the present disclosure, when an electrical signal (such as a current) is applied to the competing spin current alloy layer 101, two spin currents with opposite in-plane polarization directions are generated by the two metal elements in the alloy layer. The two spin currents compete to generate an additional out-of-plane polarized spin current, namely the competing spin current effect. The direction of its out-of-plane polarization, that is, upward or downward, is related to the polarity of the electrical signal. The additional out-of-plane polarized spin current generated by the competing spin current effect can enable the room-temperature van der Waals magnetic free layer 102 to achieve pure electrically controlled magnetic flipping without external magnetic field assistance.

[0039] According to an embodiment of the present disclosure, the room-temperature van der Waals magnetic free layer 102 is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy. The direction of the magnetic moment is controlled by the polarity of the electrical signal input to the competing spin current alloy layer 101; the room-temperature van der Waals magnetic free layer 102 provides super-room-temperature perpendicular magnetism, which can ensure that the tunnel junction device has TMR at room temperature.

[0040] The van der Waals spacer layer 103 is composed of a two-dimensional van der Waals material with a semiconductor bandgap and resistivity, or is composed of a two-dimensional van der Waals material with an insulator bandgap and resistivity; for example, the preparation materials are selected from two-dimensional hBN, two-dimensional GaSe, two-dimensional InSe, two-dimensional WSe 2 、two-dimensional WS 2 、two-dimensional MoTe 2 、two-dimensional MoSe 2By taking advantage of the characteristic that electrons passing through the van der Waals spacer layer 103 with a semiconductor or insulator bandgap maintain their polarization direction unchanged, the magnetoresistance signal is enhanced, enabling the TMR to reach over 80%.

[0041] The room-temperature van der Waals magnetic fixed layer 104 is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy. The direction of the magnetic moment is fixed and does not change with the polarity of the electrical signal input by the competing spin current alloy layer 101. The room-temperature van der Waals magnetic fixed layer 104 provides super-room-temperature perpendicular magnetism, ensuring that the tunnel junction device has TMR at room temperature.

[0042] According to another embodiment of the present disclosure, as shown in Fig. 1(b), the room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction further includes a van der Waals pinning layer 105. The van der Waals pinning layer 105 is disposed on the room-temperature van der Waals magnetic fixed layer, and the van der Waals pinning layer is composed of a room-temperature two-dimensional antiferromagnetic material. The van der Waals pinning layer 105 is composed of a room-temperature two-dimensional antiferromagnetic material, such as two-dimensional TaCoTe 2 and can further fix the direction of the magnetic moment of the room-temperature van der Waals magnetic fixed layer 104, improving the stability of the magnetic moment of the room-temperature van der Waals magnetic fixed layer 104 under strong external magnetic fields or thermal perturbations.

[0043] According to an embodiment of the present disclosure, the thicknesses of the room-temperature van der Waals magnetic free layer 102, the van der Waals spacer layer 103, the room-temperature van der Waals magnetic fixed layer 104, or the van der Waals pinning layer 105 are respectively between a single atomic layer thickness and fifty nanometers.

[0044] According to an embodiment of the present disclosure, the resistance state of the tunnel junction composed of the room-temperature van der Waals magnetic free layer, the van der Waals spacer layer, and the room-temperature van der Waals magnetic fixed layer is determined by the relative magnetization states of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer: when the magnetic moment directions of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer are the same, the tunnel junction is in a low-resistance state; when the magnetic moment directions of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer are opposite, the tunnel junction is in a high-resistance state.

[0045] In an embodiment of the present disclosure, the competing spin current alloy layer 101 in the room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction can be prepared and grown by magnetron sputtering, physical vapor deposition (PVD), etc. The remaining two-dimensional van der Waals layers can be prepared by a bottom-up exfoliation transfer method, such as mechanical exfoliation, wet and dry transfer, etc., or a bottom-up material growth method, such as chemical vapor deposition CVD, molecular beam epitaxy MBE, etc. Each layer can be prepared into a thin film with a minimum thickness of a single atomic layer. And the unit area can be controlled within 10nm 2 -100μm 2 .

[0046] The present disclosure also provides a room-temperature all-electrically controlled magnetic memory based on a two-dimensional heterojunction. As shown in Fig. 2(a), the magnetic memory includes:

[0047] The room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction as described above; and

[0048] A metal top electrode 201, disposed above the magnetic storage unit 100;

[0049] Wherein, the metal top electrode 201 serves as the data reading end of the room-temperature all-electrically controlled magnetic memory; the competing spin current alloy layer in the magnetic storage unit serves as the data writing end of the magnetic memory.

[0050] According to an embodiment of the present disclosure, as shown in Fig. 2(a), a metal top electrode 201 is disposed above the room-temperature van der Waals magnetic fixed layer 104 or the van der Waals pinning layer 105, serving as the data reading end of the room-temperature all-electrically controlled magnetic memory. The competing spin current alloy layer 101 of the room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction serves as the data writing end of the room-temperature all-electrically controlled magnetic memory.

[0051] Further, as shown in Fig. 2(b), the magnetic memory may also be provided with a metal bottom electrode 202, disposed below the competing spin current alloy layer 101 in the magnetic storage unit 100. At this time, the metal bottom electrode 202 serves as the data writing end of the magnetic memory.

[0052] The working principle of the room-temperature all-electrically controlled magnetic storage unit and memory based on a two-dimensional heterojunction is as follows:

[0053] During the information writing operation, usually only a current is applied to the competing spin current alloy layer 101 as an input electrical signal. The current generates an additional out-of-plane polarized (upward or downward) spin current through the competing spin current mechanism of the competing spin current alloy layer 101, acting on the adjacent room-temperature van der Waals magnetic free layer 102. The magnetization state of the room-temperature van der Waals magnetic free layer 102 is controlled to flip directionally according to the polarity of the current, that is, the magnetic moment direction is upward or downward. The junction resistance state is determined by the relative magnetization states of the room-temperature van der Waals magnetic free layer 102 and the room-temperature van der Waals magnetic fixed layer 104: when the magnetization directions of the room-temperature van der Waals magnetic free layer 102 and the room-temperature van der Waals magnetic fixed layer 104 are the same, the tunnel junction is in a low-resistance state; when the magnetization directions of the room-temperature van der Waals magnetic free layer 102 and the room-temperature van der Waals magnetic fixed layer 104 are opposite, the tunnel junction is in a high-resistance state. The high and low configurations of the tunnel junction resistance represent "0" and "1" in the information.

[0054] In an information reading operation, there are usually two methods: First, applying a voltage across the tunnel junction, that is, applying a voltage across the room-temperature van der Waals magnetic free layer 102, the van der Waals spacer layer 103, and the room-temperature van der Waals magnetic fixed layer 104, or applying a voltage from the metal bottom electrode 202 through the metal top electrode 201; reading the current, according to Ohm's law, the junction resistance is inversely proportional to the read current. Second, reading the voltage by applying a current across the tunnel junction, according to Ohm's law, the junction resistance is proportional to the read voltage.

[0055] The junction resistance state of the tunnel junction composed of the room-temperature van der Waals magnetic free layer 102, the van der Waals spacer layer 103, and the room-temperature van der Waals magnetic fixed layer 104 is determined by the relative magnetization states of the room-temperature van der Waals magnetic free layer 102 and the room-temperature van der Waals magnetic fixed layer 104: When the magnetic moment directions of the room-temperature van der Waals magnetic free layer 102 and the room-temperature van der Waals magnetic fixed layer 104 are antiparallel, that is, one up and one down, the junction resistance is in the high-resistance state, denoted as R AP ; When the magnetic moment directions of the room-temperature van der Waals magnetic free layer 102 and the room-temperature van der Waals magnetic fixed layer 104 are parallel, that is, both up or both down, the junction resistance is in the low-resistance state, denoted as RP. The tunneling junction resistance Generally speaking, the higher the TMR, the better, and TMR≥80% is an important indicator for whether the tunneling junction device can be applied. In the room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction used for testing, the room-temperature van der Waals magnetic free layer 102, the van der Waals spacer layer 103, and the room-temperature van der Waals magnetic fixed layer 104 are respectively made of Fe 3 GaTe 2 、WSe 2 and Fe 3 GaTe 2 fabricated. As Figure 3 shown, the left vertical axis R represents the junction resistance, the horizontal axis B represents the out-of-plane magnetic field. Under the condition of room temperature (300K), the room-temperature all-electrically controlled magnetic storage unit 100 based on a two-dimensional heterojunction has a TMR of about 85%.

[0056] So far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. It should be noted that in the accompanying drawings or the text of the specification, the implementation manners that are not depicted or described are all forms known to those of ordinary skill in the art and have not been described in detail. In addition, the above definitions of each element and method are not limited to the various specific structures, shapes, or manners mentioned in the embodiments, and those of ordinary skill in the art can make simple changes or substitutions to them.

[0057] Based on the above description, those skilled in the art should have a clear understanding of the room-temperature all-electrically controlled magnetic storage unit and memory based on a two-dimensional heterojunction of the present disclosure.

[0058] In summary, the present disclosure provides a room-temperature fully electrically controlled magnetic storage unit and a memory based on a two-dimensional heterojunction, which can achieve a tunneling magnetoresistance (TMR) of more than 80% at room temperature, and solve the problems of interface lattice mismatch, low interface flatness, or interatomic interdiffusion between interfaces of magnetic tunnel junction devices based on bulk materials, as well as the problems that the magnetic tunnel junctions based on existing two-dimensional materials do not have tunneling magnetoresistance at room temperature and have poor temperature stability.

[0059] It should also be noted that the above are different embodiments provided by the present disclosure. These embodiments are used to illustrate the technical content of the present disclosure, rather than to limit the scope of the claimed rights of the present disclosure. A feature of one embodiment can be applied to other embodiments through appropriate modification, substitution, combination, or separation.

[0060] It should be noted that, in this document, unless otherwise specified, an element with "a" does not necessarily mean only one such element, but may include one or more such elements.

[0061] In addition, in this document, unless otherwise specified, ordinal numbers such as "first", "second", etc. are only used to distinguish multiple elements with the same name, and do not indicate the existence of a rank, level, execution order, or process order between them. A "first" element and a "second" element may appear in the same component together, or in different components separately. The existence of an element with a larger ordinal number does not necessarily mean the existence of another element with a smaller ordinal number.

[0062] In this document, unless otherwise specified, the so-called feature A "or" (or) or "and / or" feature B means that A exists alone, B exists alone, or A and B exist simultaneously; the so-called feature A "and" (and) or "and" (and) or "and" feature B means that A and B exist simultaneously; the so-called "comprising", "including", "having", "containing" means including but not limited to this.

[0063] In addition, in this document, terms such as "above", "below", "left", "right", "front", "rear", or "between" are only used to describe the relative positions between multiple elements, and can be extended in interpretation to include translation, rotation, or mirroring. In addition, in this document, unless otherwise specified, the statement "one element is on another element" or a similar statement does not necessarily mean that the element contacts the other element.

[0064] In addition, unless specifically described or steps that must occur in sequence, the order of the above steps is not limited to those listed above and can be varied or rearranged according to the required design. And the above embodiments can be used in combination with each other or combined with other embodiments based on considerations of design and reliability, that is, the technical features in different embodiments can be freely combined to form more embodiments.

[0065] The specific embodiments described above have further elaborated on the purpose, technical solutions, and beneficial effects of the present disclosure. It should be understood that the above are only specific embodiments of the present disclosure and are not used to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure should be included within the protection scope of the present disclosure.

Claims

1. A room-temperature all-electrically-controlled magnetic storage unit based on a two-dimensional heterojunction, comprising: A competing spin current alloy layer, a room-temperature van der Waals magnetic free layer, a van der Waals spacer layer, and a room-temperature van der Waals magnetic fixed layer stacked from bottom to top; Wherein, the competing spin current alloy layer is composed of alloy materials with opposite spin Hall angles or alloys composed of transition metal elements with opposite spin Hall angles, and realizes pure electrically-controlled magnetic flipping of the room-temperature van der Waals magnetic free layer without external magnetic field assistance through the extra out-of-plane polarized spin current generated by the competing spin current effect; The room-temperature van der Waals magnetic free layer is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is controlled by the polarity of the electrical signal input to the competing spin current alloy layer; The van der Waals spacer layer is composed of a two-dimensional van der Waals material with a semiconductor bandgap and resistivity, or a two-dimensional van der Waals material with an insulator bandgap and resistivity; and The room-temperature van der Waals magnetic fixed layer is a two-dimensional magnetic layer with a super-room-temperature Curie temperature and perpendicular magnetic anisotropy, and the direction of the magnetic moment is fixed and does not change with the change of the polarity of the electrical signal input to the competing spin current alloy layer.

2. The magnetic storage unit according to claim 1, further comprising a van der Waals pinning layer, the van der Waals pinning layer is disposed on the room-temperature van der Waals magnetic fixed layer, and the van der Waals pinning layer is composed of a room-temperature two-dimensional antiferromagnetic material.

3. The magnetic storage unit according to claim 1, when the competing spin current alloy layer is composed of alloy materials with opposite spin Hall angles, the alloy materials with opposite spin Hall angles are alloy X-Y composed of heavy metal elements and rare earth elements, wherein, X is selected from Hf, Pt, Ta or W; Y is selected from Gd, Tb, Dy or Ho; When the competing spin current alloy layer is composed of alloy A-B composed of transition metal elements with opposite spin Hall angles, the transition metal A with a positive spin Hall angle is selected from Hf, Pt, Pd, Rh or Ru; the transition metal B with a negative spin Hall angle is selected from Ta, W, Nb or Mo.

4. The magnetic storage unit according to claim 1, wherein the room temperature van der Waals magnetic free layer and the room temperature van der Waals magnetic fixed layer are made of a two-dimensional Fe 3 GaTe 2 .

5. The magnetic storage unit according to claim 1, wherein the material for preparing the van der Waals space layer is selected from two-dimensional hBN, two-dimensional GaSe, two-dimensional InSe, two-dimensional WSe 2 , two-dimensional WS 2 , two-dimensional MoTe 2 , two-dimensional MoSe 2 .

6. The magnetic storage unit according to claim 2, wherein the material for preparing the van der Waals pinning layer comprises two-dimensional TaCoTe 2 .

7. The magnetic storage unit according to claim 2, the thickness of the room-temperature van der Waals magnetic free layer, the van der Waals spacer layer, the room-temperature van der Waals magnetic fixed layer or the van der Waals pinning layer is respectively between a single atomic layer thickness and fifty nanometers.

8. The magnetic storage unit according to claim 1, the resistance state of the tunnel junction composed of the room-temperature van der Waals magnetic free layer, the van der Waals spacer layer and the room-temperature van der Waals magnetic fixed layer is determined by the relative magnetization states of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer: when the magnetic moment directions of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer are the same, the tunnel junction is in a low-resistance state; when the magnetic moment directions of the room-temperature van der Waals magnetic free layer and the room-temperature van der Waals magnetic fixed layer are opposite, the tunnel junction is in a high-resistance state.

9. A room-temperature all-electrically-controlled magnetic memory based on a two-dimensional heterojunction, comprising: The room-temperature all-electrically-controlled magnetic storage unit based on a two-dimensional heterojunction according to any one of claims 1 to 8; and A metal top electrode disposed above the magnetic storage unit; Among them, the metal top electrode serves as the data reading end of the room-temperature all-electrically controlled magnetic memory; the competing spin current alloy layer in the magnetic storage unit serves as the data writing end of the magnetic memory.

10. The magnetic memory according to claim 9, further comprises: a metal bottom electrode disposed under the competing spin current alloy layer in the magnetic storage unit, and the metal bottom electrode serves as the data writing end of the magnetic memory.

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