A magnetic random access memory cell and methods of making and using the same

Abstract

The disclosure provides a magnetic random storage unit, comprising: a substrate, a buffer layer formed on the substrate, a first topological antiferromagnetic Weyl semimetal layer formed on the buffer layer, used for driving a 180-degree flip of a topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer by applying a current, a tunneling insulating layer formed on the first topological antiferromagnetic Weyl semimetal layer, a second topological antiferromagnetic Weyl semimetal layer formed on the tunneling insulating layer, and a protective layer formed on the second topological antiferromagnetic Weyl semimetal layer. The magnetic random storage unit is made of topological antiferromagnetic Weyl semimetal material, does not need to rely on an external magnetic field, and has high stability.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of information technology and microelectronics, and more particularly, to a magnetic random storage unit and a preparation method and a use method thereof. BACKGROUND

[0002] With the emergence of high-performance computers and mobile devices, a large amount of information is generated and needs to be stored, which promotes the research and application of storage technology and memory. Magnetic random memory using the electronic spin properties of electrons for information processing and storage has received extensive attention and research worldwide. At present, the spin transfer torque-magnetic random memory, which is vigorously developed in the market, and the spin-orbit torque-magnetic random memory, which is still in laboratory research, are both based on the flipping of the magnetic free layer magnetization in the storage unit, resulting in a change in the tunneling resistance, thereby realizing the information storage function. The traditional magnetic random storage unit is mainly based on the precise control of the magnetic moment in the ferromagnetic material, but due to the existence of intrinsic defects such as stray field and small anisotropy field, the magnetic random storage unit based on ferromagnetic material faces many challenges. In particular, with the rapid development of information technology such as big data, the Internet of Things, artificial intelligence, etc., there is an urgent need to develop a magnetic random memory with high storage density, low power consumption, scalability, and high write / read speed.

[0003] In the past few years, antiferromagnetic materials have attracted great attention in the field of spintronics due to their unique properties. First, the antiparallel arrangement of sublattice spins in antiferromagnetic materials produces a zero dipole field, making them insensitive to external magnetic field disturbances and having multiple levels of stability, which can be used for high-density, multi-state storage and neural network computing. Second, the spin dynamics of antiferromagnetic materials are several orders of magnitude higher than those of ferromagnetic materials. Due to the strong exchange coupling between sublattice spins, the coherent spin precession frequency (antiferromagnetic resonance) of antiferromagnetic materials is in the terahertz range, while the resonance frequency of ferromagnetic materials with weak anisotropy fields is in the gigahertz range, so antiferromagnetic materials have great application potential in the terahertz field. Some special and irreplaceable advantages of antiferromagnetic materials compared to ferromagnetic materials make the study of antiferromagnetic random storage units a promising field for basic research and device technology. However, current research has shown that the readout signal of magnetic random storage units based on conventional linear antiferromagnetic materials is very weak, greatly limiting the application of antiferromagnetic materials in magnetic random storage units. How to achieve a large signal output in magnetic random storage units based on antiferromagnetic materials is an urgent problem that needs to be solved in the field of information storage and processing.

[0004] DISCLOSURE

[0005] Therefore, the present disclosure proposes a magnetic random storage unit based on topological antiferromagnetic Weyl semimetals to at least partially solve the above technical problems.

[0006] One aspect of the present disclosure provides a magnetic random storage unit, characterized in that comprising: a substrate; a buffer layer formed on the substrate; a first topological antiferromagnetic Weyl semimetal layer formed on the buffer layer, for driving a 180° flip of a topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer by applying a current; a tunneling insulating layer formed on the first topological antiferromagnetic Weyl semimetal layer; a second topological antiferromagnetic Weyl semimetal layer formed on the tunneling insulating layer; and a protective layer formed on the second topological antiferromagnetic Weyl semimetal layer.

[0007] Optionally, the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are made of a non-linear antiferromagnetic material, including one or a combination of Mn3Sn, Mn3Ge, Mn3Ni, Mn3Cu, Mn3Zn, Mn3Ga, Mn3Pd, Mn3In, Mn3Ir, Mn3Pt.

[0008] Optionally, when the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

[0009] Optionally, when the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

[0010] Optionally, the thickness of the tunneling insulating layer is 0.5-3 nm.

[0011] Another aspect of the present disclosure provides a preparation method of a magnetic random storage unit, characterized in that comprising: growing a buffer layer on a substrate; growing a first topological antiferromagnetic Weyl semimetal layer on the buffer layer; growing a tunneling insulating layer on the first topological antiferromagnetic Weyl semimetal layer; growing a second topological antiferromagnetic Weyl semimetal on the tunneling insulating layer; and growing a protective layer on the second topological antiferromagnetic Weyl semimetal layer.

[0012] Optionally, when the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are annealed, an external magnetic field is used to control the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer.

[0013] Optionally, the method further comprises: controlling the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer, including: when the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer; when the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

[0014] Another aspect of the present disclosure also provides a method for using a magnetic random storage unit, the magnetic random storage unit comprising: initializing by using an external magnetic field, so that the magnetic moment directions of the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are the same; and causing the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer to produce a 180° flip by applying a pulse voltage to the first topological antiferromagnetic Weyl semimetal layer.

[0015] Optionally, the method further comprises: reading the voltage between the first topological antiferromagnetic Weyl semimetal layer and the protective layer, and taking the change of the tunneling resistance of the magnetic random storage unit as output information.

[0016] From the above technical solutions, the magnetic random storage unit, the preparation method and the use method of the present disclosure at least have the following beneficial effects:

[0017] (1) The present disclosure no longer uses a conventional magnetic random storage unit prepared based on a ferromagnetic material, but proposes an information carrier material taking a topological antiferromagnetic Weyl semimetal as a spin-orbit torque device, controls the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer to produce a 180° flip through the intrinsic spin-orbit torque effect induced by the current in the first topological antiferromagnetic Weyl semimetal layer, and thus realizes a magnetic random storage unit prepared based on a topological antiferromagnetic Weyl semimetal material.

[0018] (2) The information device based on the topological antiferromagnetic Weyl semimetal material has the advantages of no external magnetic field dependence, high stability, high speed, low power consumption, long service life, etc., and can be applied to the fields of nonvolatile high-energy-efficiency storage, storage-computing integration, brain-like computing, etc. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Fig. 1 schematically shows a schematic diagram of a magnetic random storage unit according to an embodiment of the present disclosure;

[0020] Figure 2A flow chart of a method of manufacturing a magnetic random storage unit according to embodiments of the present disclosure is schematically shown;

[0021] Figure 3 A flow chart of a method of using a magnetic random storage unit according to embodiments of the present disclosure is schematically shown;

[0022] Figure 4A A schematic diagram of information writing / reading of a V-V type magnetic random storage unit in an initial state according to embodiments of the present disclosure is schematically shown;

[0023] Figure 4B A schematic diagram of information writing / reading of a V-V type magnetic random storage unit under application of a pulse voltage (generating a pulse current) according to embodiments of the present disclosure is schematically shown;

[0024] Figure 5A A schematic diagram of information writing / reading of a P-P type magnetic random storage unit in an initial state according to embodiments of the present disclosure is schematically shown;

[0025] Figure 5B A schematic diagram of information writing / reading of a P-P type magnetic random storage unit under application of a pulse voltage (generating a pulse current) according to embodiments of the present disclosure is schematically shown.

[0026] BRIEF DESCRIPTION OF DRAWINGS

[0027] 100 - substrate;

[0028] 200 - buffer layer;

[0029] 300 - first topological antiferromagnetic Weyl semimetal layer;

[0030] 400 - tunneling insulating layer;

[0031] 500 - second topological antiferromagnetic Weyl semimetal layer;

[0032] 600 - protective layer. DETAILED DESCRIPTION

[0033] So that the objectives, technical solutions, and advantages of the present disclosure are more clearly understood, the following further describes the present disclosure in conjunction with specific embodiments and with reference to the accompanying drawings.

[0034] Some but not all embodiments of the present disclosure will be shown in greater detail in the accompanying drawings, in which some embodiments of the present disclosure will be shown schematically. In fact, various embodiments of the present disclosure can be implemented in many different forms and should not be interpreted as being limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure satisfies applicable legal requirements.

[0035] Figure 1A magnetic random storage unit is shown schematically according to an embodiment of the present disclosure.

[0036] As shown in the figure, the magnetic random storage unit comprises a substrate 100, a buffer layer 200, a first topological antiferromagnetic Weyl semimetal layer 300, a tunneling insulating layer 400, a second topological antiferromagnetic Weyl semimetal layer 500, and a protective layer 600. Figure 1 The buffer layer 200 is formed on the substrate 100; the first topological antiferromagnetic Weyl semimetal layer 300 is formed on the buffer layer 200, and is used to drive a 180° flip of a topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300 by applying a current; the tunneling insulating layer 400 is formed on the first topological antiferromagnetic Weyl semimetal layer 300; the second topological antiferromagnetic Weyl semimetal layer 500 is formed on the tunneling insulating layer 400; and the protective layer 600 is formed on the second topological antiferromagnetic Weyl semimetal layer 500.

[0037] The substrate 100 can be a silicon wafer, a glass wafer, or an MgO wafer.

[0038] The buffer layer 200 and the protective layer 600 can be made of a metal material.

[0039] The first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 correspond to the free layer and the pinned layer of a conventional magnetic random storage unit, and are both made of a topological antiferromagnetic Weyl semimetal material. The topological antiferromagnetic Weyl semimetal material mainly includes Mn3Sn, Mn3Ge, Mn3Ni, Mn3Cu, Mn3Zn, Mn3Ga, Mn3Pd, Mn3In, Mn3Ir, Mn3Pt, and other nonlinear antiferromagnetic materials.

[0040] The first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are oppositely arranged and have consistent easy magnetization directions. For example, when the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is also perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer. When the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is also parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

[0041]

[0042] ​In the absence of an external magnetic field, a pulsed current is applied to the first topological antiferromagnetic Weyl semimetal layer 300, and the intrinsic spin-orbit torque effect induced by the current in the first topological antiferromagnetic Weyl semimetal layer 300 can control the 180° directional flip of the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300.

[0043] The above is a magnetic random storage unit according to an embodiment of the present disclosure. Through the intrinsic spin-orbit torque effect induced by the current in the first topological antiferromagnetic Weyl semimetal layer 300, the 180° flip of the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer is caused, and the tunneling resistance is changed. The magnetic random storage unit of the present disclosure can realize the functions of the traditional magnetic random storage unit based on ferromagnetic materials without relying on an external magnetic field.

[0044] Figure 2 A method for preparing a magnetic random storage unit according to an embodiment of the present disclosure is schematically shown. As shown in Figure 2 The preparation method is as follows, mainly including steps S210-S250.

[0045] Step S210: growing a buffer layer 200 on a substrate 100.

[0046] The substrate 100 can be a silicon wafer, a glass wafer, or an MgO wafer. The buffer layer 200 can be made of a metal material. The buffer layer 200 is preferably prepared by magnetron sputtering. The buffer layer 200 can make the subsequently grown thin film smoother and more uniform.

[0047] Step S220: growing a first topological antiferromagnetic Weyl semimetal layer 300 on the buffer layer 200.

[0048] The first topological antiferromagnetic Weyl semimetal layer 300 corresponds to the free layer of the traditional magnetic random storage unit. The first topological antiferromagnetic Weyl semimetal layer 300 can use Mn3Sn, Mn3Ge, Mn3Ni, Mn3Cu, Mn3Zn, Mn3Ga, Mn3Pd, Mn3In, Mn3Ir, Mn3Pt, etc. nonlinear antiferromagnetic material. The first topological antiferromagnetic Weyl semimetal layer 300 is prepared by magnetron sputtering. By using an external magnetic field during annealing, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer 300 is controlled to be the same as that of the second topological antiferromagnetic Weyl semimetal layer 500. After successful preparation, a pulsed current is applied to the first topological antiferromagnetic Weyl semimetal layer 300 in the absence of an external magnetic field, and the intrinsic spin-orbit torque effect induced by the current in the topological antiferromagnetic Weyl semimetal can control the 180° directional flip of the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300.

[0049] Step S230, growing a tunneling insulating layer 400 on the first topological antiferromagnetic Weyl semimetal layer 300.

[0050] The tunneling insulating layer 400 material can be MgO or AlO x and the like, and the preparation method preferably adopts magnetron sputtering. In the embodiment of the present disclosure, the tunneling insulating layer 400 preferably has a thickness controlled in a range of 0.5-3 nm.

[0051] Step S240: growing a second topological antiferromagnetic Weyl semimetal layer 500 on the tunneling insulating layer 400.

[0052] The second topological antiferromagnetic Weyl semimetal layer 500 corresponds to a pinning layer of a conventional magnetic random storage unit. The second topological antiferromagnetic Weyl semimetal can use nonlinear antiferromagnetic materials such as Mn3Sn, Mn3Ge, Mn3Ni, Mn3Cu, Mn3Zn, Mn3Ga, Mn3Pd, Mn3In, Mn3Ir, Mn3Pt, etc. The second topological antiferromagnetic Weyl semimetal layer 500 is prepared by using magnetron sputtering. By using an external magnetic field in the process of annealing, the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer 500 is controlled to be perpendicular or parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer 500, and the easy magnetization direction is the same as that of the first topological antiferromagnetic Weyl semimetal layer 300, and different magnetic anisotropies are obtained.

[0053] Step S250: growing a protective layer 600 on the second topological antiferromagnetic Weyl semimetal layer 500.

[0054] The protective layer 600 can be made of a metal material and prepared by using magnetron sputtering.

[0055] The above is a typical preparation method of a magnetic random storage unit based on a topological antiferromagnetic Weyl semimetal material in the embodiment. According to actual needs, a plurality of cylindrical or other shaped structure units are made on the basic multilayer film structure by etching and the like. The cylindrical magnetic random storage units prepared by the above method are connected in series, and an insulating material is filled between the units to form a random memory.

[0056] Further, the multilayer film structure prepared by the above preparation method can also be used to prepare a magnetoresistor. Based on a topological antiferromagnetic Weyl semimetal material, a plurality of cylindrical or other shaped structures are made on the basic multilayer film structure by etching and the like. The magnetoresistor can be a giant magnetoresistance device or an anisotropic tunneling magnetoresistance device. The magnetoresistor can be used as a sensor, an isolator and the like.

[0057] Figure 3 A method for using the magnetic random storage unit of the present disclosure is shown schematically, which is applied to the magnetic random storage unit as above. As shown in the figure, the method for using includes steps S310-S320.

[0058] In step S310, the magnetic moments of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are initialized to be in the same direction by applying an external magnetic field.

[0059] In step S320, the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300 is flipped by 180° by applying a pulse voltage to the first topological antiferromagnetic Weyl semimetal layer 300.

[0060] Embodiment 1

[0061] Figure 4A The information write / read schematic diagram of the V-V type magnetic random storage unit of the present disclosure in the initial state is shown. For the V-V type magnetic random storage unit, the easy magnetization directions of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are perpendicular to the surface of the second topological antiferromagnetic Weyl semimetal layer

[0062] In step S310, the magnetic moments of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are initialized to be in the same direction by applying an external magnetic field.

[0063] By applying a small constant current source I between the first topological antiferromagnetic Weyl semimetal layer 300 and the protective layer 600, the magnetic tunneling resistance is detected, and it is found that the tunneling resistance is in a low state at this time.

[0064] In step S320, the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300 is flipped by 180° by applying a positive pulse voltage U (generating a positive pulse current) to the first topological antiferromagnetic Weyl semimetal layer 300, and the information write / read schematic diagram of the V-V type magnetic random storage unit after applying a pulse voltage (generating a pulse current) is obtained as shown in Figure 4B At this time, by reading the voltage V between the first topological antiferromagnetic Weyl semimetal layer and the protective layer, the jump of the tunneling resistance can be detected, and the magnetic random storage unit can write a signal of "1".

[0065] By inputting a negative pulse voltage U (generating a negative pulse current) in the topological antiferromagnetic Weyl semimetal layer 300, the topological antiferromagnetic state in the topological antiferromagnetic Weyl semimetal layer 300 is restored, resulting in a jump in the tunneling resistance. By reading the change in the value of V, the change in the tunneling resistance is detected, and the magnetic random storage unit writes a "0" signal.

[0066] Embodiment 2

[0067] Figure 5A An information write / read schematic diagram of a P-P type magnetic random storage unit in an initial state is provided. The magnetic random storage unit of the present embodiment is different from that of Embodiment 1 in that the magnetic moments of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are parallel to the layer surface of the second topological antiferromagnetic Weyl semimetal layer 500 when the magnetic random storage unit is prepared.

[0068] By step S310, the magnetic moments of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are initialized by an applied magnetic field, so that the directions of the magnetic moments of the two layers are the same, i.e., the magnetic moments are parallel, both perpendicular to the layer surface of the second topological antiferromagnetic Weyl semimetal layer 500.

[0069] By applying a small constant current source I between the first topological antiferromagnetic Weyl semimetal layer 300 and the protective layer 600, the tunneling resistance is detected, and it is found that the tunneling resistance is in a low state at this time.

[0070] By step S320, a positive pulse voltage U (generating a positive pulse current) is applied to the first topological antiferromagnetic Weyl semimetal layer 300, so that the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300 is flipped by 180°, and the information write / read schematic diagram of a V-V type magnetic random storage unit after applying a pulse voltage (generating a pulse current) is as shown in Figure 5B By reading the voltage V between the first topological antiferromagnetic Weyl semimetal layer and the protective layer, the jump in the tunneling resistance can be detected, and the magnetic random storage unit can write a "1" signal.

[0071] By inputting a negative pulse voltage U (generating a negative pulse current) in the topological antiferromagnetic Weyl semimetal layer 300, the topological antiferromagnetic state in the topological antiferromagnetic Weyl semimetal layer 300 is restored, resulting in a jump in the tunneling resistance. By reading the change in the value of V, the change in the tunneling resistance is detected, and the magnetic random storage unit writes a "0" signal.

[0072] Thus far, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. Note that the implementation that is not illustrated or described in the drawings or the description is known to those skilled in the art and thus not described in detail. In addition, the definitions of the components and the method described above are not limited to the various specific structures, shapes, or manners mentioned in the embodiments, and can be simply changed or replaced by those skilled in the art.

[0073] Based on the above description, those skilled in the art should have a clear understanding of the magnetic random storage unit based on the topological antiferromagnetic Weyl semimetal, and the preparation method and use method thereof.

[0074] In summary, the present disclosure no longer uses a conventional magnetic random storage unit prepared based on a ferromagnetic material, proposes to use a topological antiferromagnetic Weyl semimetal as an information carrier material of a spin-orbit torque device, controls the 180° flip of the topological antiferromagnetic state in the topological antiferromagnetic Weyl semimetal layer through the intrinsic spin-orbit torque effect induced by the current in the topological antiferromagnetic Weyl semimetal layer, and thus realizes a magnetic random storage unit based on the topological antiferromagnetic Weyl semimetal material.

[0075] The information device based on the topological antiferromagnetic Weyl semimetal material has the advantages of no external magnetic field dependence, high stability, high speed, low power consumption, long service life, and the like, and can be applied to the fields of nonvolatile high-energy-efficiency storage, storage-computing integration, and brain-like computing.

[0076] In addition, the shape and size of each component in the drawings do not reflect the actual size and ratio, but only illustrate the content of the embodiments of the present disclosure. In addition, in the claims, any reference symbol located between parentheses should not be construed as a limitation on the claims.

[0077] Unless otherwise known as the opposite meaning, the numerical parameters in the specification and the attached claims are approximate values, which can be changed according to the desired characteristics obtained by the content of the present disclosure. Specifically, all the numbers used in the specification and the claims to express the content of the composition, reaction conditions, and the like should be understood as being modified by the term "about" in all cases. Generally, it means that it includes a change of ±10% in some embodiments, a change of ±5% in some embodiments, a change of ±1% in some embodiments, and a change of ±0.5% in some embodiments.

[0078] Furthermore, the word "comprise" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0079] The use of ordinal numbers such as "first", "second", "third" and the like in the specification and claims is used to modify a respective element and does not imply any order or sequence of the elements, or of the method steps, but is merely used to identify the respective elements or steps in a clear and unambiguous manner.

[0080] The above detailed description of the specific embodiments of the present disclosure is merely for the purpose of illustrating the principles of the present disclosure, and should not be taken in a limiting sense. Any modification, equivalent replacement, improvement, and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A magnetic random access memory cell comprising: The method comprises: a substrate; a buffer layer formed on the substrate; a first topological antiferromagnetic Weyl semimetal layer formed on the buffer layer, used to drive a 180° flip of a topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer by applying a current; a tunneling insulating layer formed on the first topological antiferromagnetic Weyl semimetal layer; a second topological antiferromagnetic Weyl semimetal layer formed on the tunneling insulating layer; a protective layer formed on the second topological antiferromagnetic Weyl semimetal layer.

2. The magnetic random access memory cell of claim 1, wherein, The first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are made of a nonlinear antiferromagnetic material, and the nonlinear antiferromagnetic material includes one or a combination of Mn3Sn, Mn3Ge, Mn3Ni, Mn3Cu, Mn3Zn, Mn3Ga, Mn3Pd, Mn3In, Mn3Ir, and Mn3Pt.

3. The magnetic random access memory cell of claim 1, wherein, When the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

4. The magnetic random access memory cell of claim 1, wherein, When the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

5. The magnetic random access memory cell of claim 1, wherein, The thickness of the tunneling insulating layer is 0.5-3 nm.

6. A method of fabricating a magnetic random access memory cell, comprising: The method comprises: growing a buffer layer on a substrate; growing a first topological antiferromagnetic Weyl semimetal layer on the buffer layer; growing a tunneling insulating layer on the first topological antiferromagnetic Weyl semimetal layer; growing a second topological antiferromagnetic Weyl semimetal layer on the tunneling insulating layer; growing a protective layer on the second topological antiferromagnetic Weyl semimetal layer.

7. The method for preparing a magnetic random storage unit according to claim 6, wherein when the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are annealed, an external magnetic field is used to control the easy magnetization directions of the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer.

8. The method of claim 7, wherein the magnetic random access memory cell is formed by a process comprising: The control of the easy magnetization directions of the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer comprises: when the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer. When the easy magnetization direction of the second topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

9. A method of using a magnetic random access memory cell as claimed in any one of claims 1 to 5, wherein: Comprising: Using an applied magnetic field to initialize, so that the magnetic moment direction of the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are the same; By applying a pulse voltage to the first topological antiferromagnetic Weyl semimetal layer, the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer is flipped by 180°.

10. The method of using a magnetic random access memory cell of claim 9, wherein, Comprising: By reading the voltage between the first topological antiferromagnetic Weyl semimetal layer and the protective layer, the change of the tunneling resistance of the magnetic random storage unit is taken as the output information.

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