CN115589764A - A kind of magnetic random storage unit and its preparation method and use method - Google Patents

Abstract

The present disclosure provides a magnetic random access memory cell comprising: the device comprises a substrate, a buffer layer, a first topological antiferromagnetic Weyl half metal layer, a tunneling insulation layer and a protective layer, wherein the buffer layer is formed on the substrate, the first topological antiferromagnetic Weyl half metal layer is formed on the buffer layer and used for driving a topological antiferromagnetic state in the first topological antiferromagnetic Weyl half metal layer to generate 180-degree turnover through applying current, the tunneling insulation layer is formed on the first topological antiferromagnetic Weyl half metal layer, the second topological antiferromagnetic Weyl half metal layer is formed on the tunneling insulation layer, and the protective layer is formed on the second topological antiferromagnetic Weyl half metal layer. The topological antiferromagnetic Weyl semimetal is used as a material to manufacture the magnetic random memory unit, an external magnetic field is not required to be relied on, and the stability is high.

Description

A kind of magnetic random storage unit and its preparation method and use method

technical field

The disclosure relates to the fields of information technology and microelectronics, and more specifically, to a magnetic random access memory unit, a preparation method, and a use method thereof.

Background technique

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. The magnetic random access memory, which uses the electron spin property of electrons to process and store information, has attracted extensive attention and research all over the world. At present, the commercially developed spin-transfer torque-magnetic random access memory and the spin-orbit moment-magnetic random access memory that is still in laboratory research are all based on the reversal of the magnetization of the magnetic free layer in the storage unit, resulting in a change in the tunneling resistance. So as to realize the storage function of information. Traditional MRAM units are mainly based on the precise control of the magnetic moments in ferromagnetic materials, but due to the existence of intrinsic defects such as stray fields and small anisotropy fields, MRAM units based on ferromagnetic materials are facing Many challenges. In particular, with the rapid development of information technologies such as big data, the Internet of Things, and artificial intelligence, there is an urgent need to develop magnetic random access memory with high storage density, low power consumption, scalability, and high write/read speed.

In the past few years, antiferromagnetic materials have attracted great attention from the spintronics community due to their unique properties. First of all, the antiparallel arrangement of sublattice spins in antiferromagnetism produces a zero dipole field, making it insensitive to external magnetic field disturbances and having multi-level stability, which can be used for high-density, multi-state storage and neuromorphic computing; Second, the spin dynamics of antiferromagnetism are several orders of magnitude higher than those of ferromagnetism. Its coherent spin precession frequency (antiferromagnetic resonance) is in the terahertz range due to the strong exchange coupling between the sublattice spins, while the ferromagnetic resonance frequency with weaker anisotropy field is in the gigahertz range , so antiferromagnetism has great application potential in the terahertz field. Compared with ferromagnetism, antiferromagnetism has some special and irreplaceable advantages, which makes antiferromagnetic random memory cells open up broad prospects for basic research and device technology. However, current research shows that the readout signal is very weak due to the magnetic random access memory cells prepared based on conventional linear antiferromagnetic materials, which greatly limits the application of antiferromagnetic materials in magnetic random access memory cells. How to achieve a large signal output in the magnetic random access memory cell based on antiferromagnetic materials is an urgent problem to be solved in the field of information storage and processing.

public content

In view of this, the present disclosure proposes a magnetic random access memory unit based on a topological antiferromagnetic Weyl semimetal to at least partly solve the above-mentioned technical problems.

One aspect of the present disclosure provides a magnetic random access memory unit, which is characterized in that it includes: a substrate; a buffer layer formed on the substrate; a first topological antiferromagnetic Weyl semimetal layer formed on the buffer layer, By applying current, the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semi-metal layer is driven to produce a 180° flip; the tunneling insulating layer is formed on the first topological antiferromagnetic Weyl semi-metal layer; the second topological The antiferromagnetic Weyl semimetal layer is formed on the tunnel insulating layer; the protection layer is formed on the second topological antiferromagnetic Weyl semimetal layer.

Optionally, the first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer are made of non-linear antiferromagnetic materials, including Mn ₃ Sn, Mn ₃ Ge, Mn ₃ Ni, Mn One or more combinations of ₃ Cu, M _nn3 Zn, Mn ₃ Ga, Mn ₃ Pd, Mn ₃ In, Mn ₃ Ir, M _nn3 Pt.

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 of the first topological antiferromagnetic Weyl semimetal layer The direction is perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

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 of the first topological antiferromagnetic Weyl semimetal layer The direction is parallel to the surface direction of the second topological antiferromagnetic Weyl semimetal layer.

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

Another aspect of the present disclosure provides a method for preparing a magnetic random access memory unit, which is characterized by comprising: growing a buffer layer on a substrate; growing a first topological antiferromagnetic Weyl semimetal layer on the buffer layer; A tunnel insulating layer is grown on the topological antiferromagnetic Weyl semimetal layer; a second topological antiferromagnetic Weyl semimetal is grown on the tunnel insulating layer; a protective layer is grown on the second topological antiferromagnetic Weyl semimetal layer.

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 first topological antiferromagnetic Weyl semimetal layer and the second topological antiferromagnetic Weyl semimetal layer. The easy magnetization direction of the magnetic Weyl semimetal layer.

Optionally, controlling the easy magnetization direction of the first topological antiferromagnetic Weyl half-metal layer and the second topological antiferromagnetic Weyl half-metal layer includes: when the easy magnetization direction of the second topological antiferromagnetic Weyl half-metal layer is vertical During the surface direction of the second topological antiferromagnetic Weyl half-metal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl half-metal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl half-metal layer; when the second When the easy magnetization direction of the topological antiferromagnetic Weyl half-metal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl half-metal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl half-metal layer is parallel to the second topological Surface orientation of an antiferromagnetic Weyl semimetal layer.

Another aspect of the present disclosure also provides a method for using a magnetic random access memory unit. The magnetic random access memory unit is as shown in claims 1 to 5, characterized in that it includes: initializing with an external magnetic field, so that the first topological antiferromagnetic Weyl semi The magnetic moment directions of the metal 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 layer in the first topological antiferromagnetic Weyl semimetal layer The magnetic state produces a 180° flip.

Optionally, the using method further includes: taking the change of the tunneling resistance of the magnetic random memory cell as output information by taking the voltage between the first topological antiferromagnetic Weyl semi-metal layer and the protective layer.

It can be seen from the above technical solutions that the magnetic random access memory unit, preparation method and use method of the present disclosure have at least the following beneficial effects:

(1) This disclosure no longer uses conventional magnetic random access memory cells based on ferromagnetic materials, but proposes an information carrier material that uses topological antiferromagnetic Weyl semimetals as spin-orbit moment devices, through the first topological antiferromagnetic The current-induced intrinsic spin-orbit torque effect in the magnetic Weyl semimetal layer controls the 180° flip of the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer, thereby realizing the material based on topological antiferromagnetic Weyl semimetal Prepared magnetic random access memory unit.

(2) Information devices based on topological antiferromagnetic Weyl semimetal materials have the advantages of no external magnetic field dependence, high stability, fast speed, low power consumption, and long service life, and can be applied to non-volatile high-energy-efficiency storage, storage and computing Integration, brain-like computing and other fields.

Description of drawings

FIG. 1 schematically shows a schematic diagram of a magnetic random access memory unit according to an embodiment of the present disclosure;

Fig. 2 schematically shows a flow chart of a method for manufacturing a magnetic random access memory unit according to an embodiment of the present disclosure;

FIG. 3 schematically shows a flowchart of a method for using a magnetic random access memory unit according to an embodiment of the present disclosure;

FIG. 4A schematically shows a schematic diagram of information writing/reading of a V-V type magnetic random access memory unit in an initial state according to an embodiment of the present disclosure;

Fig. 4B schematically shows a schematic diagram of information writing/reading of a V-V type magnetic random access memory unit under the application of pulse voltage (generating pulse current) according to an embodiment of the present disclosure;

FIG. 5A schematically shows a schematic diagram of information writing/reading in the initial state of a P-P type magnetic random access memory unit according to an embodiment of the present disclosure;

FIG. 5B schematically shows a schematic diagram of information writing/reading of a P-P type magnetic random access memory unit under application of pulse voltage (generating pulse current) according to an embodiment of the present disclosure.

Explanation of reference signs:

100-substrate;

200-buffer layer;

300-the first topological antiferromagnetic Weyl semimetal layer;

400-tunneling insulation layer;

500 - the second topological antiferromagnetic Weyl semimetal layer;

600 - protective layer.

detailed description

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

Certain embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which some but not all embodiments are shown. Indeed, various embodiments of the disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth here; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.

FIG. 1 schematically shows a magnetic random access memory unit according to an embodiment of the present disclosure.

As shown in FIG. 1 , the magnetic random access memory unit includes: a substrate 100, a buffer layer 200, a first topological antiferromagnetic Weyl semimetal layer 300, a tunnel insulating layer 400, a second topological antiferromagnetic Weyl semimetal layer 500 and protective layer 600 .

Wherein, 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 the first topological antiferromagnetic Weyl semimetal layer by applying an electric current The topological antiferromagnetic state in 300 produces a 180° flip; 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 On the layer 400 ; the protection layer 600 is formed on the second topological antiferromagnetic Weyl semimetal layer 500 .

The substrate 100 may be a silicon wafer, a glass wafer or a MgO substrate.

The buffer layer 200 and the protection layer 600 may be made of metal materials.

The first topological antiferromagnetic Weyl semimetal 300 and the second topological antiferromagnetic Weyl semimetal 500 are equivalent to the free layer and the pinned layer of a traditional MRAM unit, and are both made of topological antiferromagnetic Weyl semimetal materials. Among them, the topological antiferromagnetic Weyl semimetal materials are mainly Mn ₃ Sn, Mn ₃ Ge, Mn ₃ Ni, Mn ₃ Cu, Mn ₃ Zn, Mn ₃ Ga, Mn ₃ Pd, Mn ₃ In, Mn ₃ Ir, Mn ₃ Non-linear antiferromagnetic materials such as Pt.

The first topological antiferromagnetic Weyl half-metal 300 and the second topological antiferromagnetic Weyl half-metal 500 are arranged oppositely, and the directions of easy magnetization are consistent. 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 perpendicular to the surface direction of the second topological antiferromagnetic Weyl semimetal layer. When the easy magnetization direction of the second topological antiferromagnetic Weyl half-metal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl half-metal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl half-metal layer is parallel to Surface orientation of a second topological antiferromagnetic Weyl semimetal layer.

In the absence of an external magnetic field, a pulse current is applied in 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 be The topological antiferromagnetic state in the first topological antiferromagnetic Weyl semi-metal layer 300 is controlled to generate 180° orientation flip.

The above is a magnetic random memory 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 first topological antiferromagnetic Weyl semimetal layer The topological antiferromagnetic state produces a 180° flip, which changes the tunneling resistance. The magnetic random storage unit of the present disclosure does not depend on an external magnetic field, and can realize the functions realized by the traditional magnetic random storage unit based on ferromagnetic materials.

FIG. 2 schematically shows a method for manufacturing a magnetic random access memory unit according to an embodiment of the present disclosure. As shown in FIG. 2, the preparation method is as follows, mainly including steps S210-S250.

Step S210 : growing a buffer layer 200 on the substrate 100 .

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

Step S220 , growing a first topological antiferromagnetic Weyl semimetal layer 300 on the buffer layer 200 .

The first topological antiferromagnetic Weyl semi-metal layer 300 is equivalent to the free layer of a conventional MRAM unit. The first topological antiferromagnetic Weyl semi-metal layer 300 can use Mn ₃ Sn, Mn ₃ Ge, Mn ₃ Ni, Mn ₃ Cu, Mn ₃ Zn, Mn ₃ Ga, Mn ₃ Pd, Mn ₃ In, Mn ₃ Ir, Mn ₃ Pt and other nonlinear antiferromagnetic materials. The first topological antiferromagnetic Weyl semimetal layer 300 is prepared by magnetron sputtering. During the annealing process, the easy magnetization direction of the first topological antiferromagnetic Weyl half-metal layer 300 is controlled by an external magnetic field, so that the easy magnetization direction of this layer is the same as that of the second topological antiferromagnetic Weyl half-metal layer 500 . After the preparation is successful, in the absence of an external magnetic field, a pulse 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 topological antiferromagnetic Weyl semimetal can be The topological antiferromagnetic state in the first topological antiferromagnetic Weyl semi-metal layer 300 is controlled to generate 180° orientation flip.

Step S230 , growing a tunnel insulating layer 400 on the first topological antiferromagnetic Weyl semi-metal layer 300 .

The material of the tunneling insulating layer 400 may be MgO or _AlOx , etc., and the preparation method preferably adopts magnetron sputtering. In the embodiment of the present disclosure, the thickness of the tunneling insulating layer 400 is preferably controlled at 0.5-3 nm.

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

The second topological antiferromagnetic Weyl semi-metal layer 500 is equivalent to the pinning layer of a conventional MRAM cell. The second topological antiferromagnetic Weyl semimetal can use Mn ₃ Sn, Mn ₃ Ge, Mn ₃ Ni, Mn ₃ Cu, Mn ₃ Zn, Mn ₃ Ga, Mn ₃ Pd, Mn ₃ In, Mn ₃ Ir, Mn ₃ Pt and other nonlinear antiferromagnetic materials. The second topological antiferromagnetic Weyl semimetal layer 500 is prepared by magnetron sputtering. During the annealing process, the easy magnetization direction of the second topological antiferromagnetic Weyl half-metal layer 500 is controlled by using an external magnetic field, so that the easy magnetization direction is perpendicular to or parallel to that of the second topological antiferromagnetic Weyl half-metal layer 500 The surface direction is the same as the easy magnetization direction of the first topological antiferromagnetic Weyl semi-metal layer 300 , and different magnetic anisotropy is obtained.

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

The protective layer 600 can be made of metal material and prepared by magnetron sputtering.

The above is a typical preparation method of the MRAM unit based on the topological antiferromagnetic Weyl semimetal material in this embodiment. And on this multi-layer film structure, according to actual needs, through etching and other methods, a plurality of cylindrical or other shaped structural units are produced on this basic multi-layer film structure. In the embodiment of the present disclosure, the cylindrical magnetic random access memory units prepared by the above method are connected in series, and insulating material is filled between each unit to form a random access memory.

Further, the multilayer film structure prepared by the above preparation method can also be used to prepare magnetoresistors. Based on the topological antiferromagnetic Weyl semi-metallic material to prepare a multi-layer film structure, according to actual needs, through etching and other methods, on this basic multi-layer film structure, make a plurality of cylindrical or other shaped structures. The magnetoresistor can be a giant magnetoresistance device or an anisotropic tunnel magnetoresistance device. Magnetoresistive devices can be used as sensors, isolators and other devices.

FIG. 3 schematically shows a method for using a magnetic random access memory unit of the present disclosure, which is applied to the above magnetic random access memory unit. As shown in the figure, the usage method includes steps S310-S320.

Step S310 , initializing with an external magnetic field, so that the magnetic moment directions of the first topological antiferromagnetic Weyl half-metal layer 300 and the second topological antiferromagnetic Weyl half-metal layer 500 are the same.

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

Example 1

FIG. 4A is a schematic diagram of information writing/reading of the V-V type magnetic random access memory cell in the initial state of the present disclosure. For the V-V type magnetic random memory unit, the easy magnetization direction of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 is perpendicular to the surface of the second topological antiferromagnetic Weyl semimetal layer

Through step S310, an external magnetic field is used to initialize, so that the magnetic moment directions of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are the same, that is, the magnetic moment directions of the two layers are arranged in parallel , are perpendicular to the surface of the second topological antiferromagnetic Weyl semimetal layer 500,

By applying a small constant current source I between the first topological antiferromagnetic Weyl semi-metal 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.

Through step S320, by applying a positive pulse voltage U (generating a positive pulse current) to the first topological antiferromagnetic Weyl semimetal layer 300, the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300 is generated by 180° Turn over to obtain the information writing/reading schematic diagram of the V-V type magnetic random access memory cell shown in Figure 4B after applying a pulse voltage (generating a pulse current). At this time, by reading the first topological antiferromagnetic Weyl semi-metal layer The voltage V between the protection layer and the jump of the tunneling resistance can be detected, and the magnetic random memory unit can write a signal of "1".

After inputting a negative pulse voltage U (to generate a negative pulse current) in the topological antiferromagnetic Weyl semimetal layer 300, the topological antiferromagnetic state in the topological antiferromagnetic Weyl semimetal layer 300 recovers, resulting in a jump in the tunneling resistance . By reading the change of the V value and detecting the change of the tunnel resistance, the magnetic random memory unit writes a signal of "0".

Example 2

FIG. 5A provides a schematic diagram of information writing/reading of a P-P type magnetic random access memory cell in an initial state. Compared with Example 1, the magnetic random access memory unit of this embodiment differs in that the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 use an externally applied The magnetic moment initialized by the magnetic field is parallel to the layer surface of the second topological antiferromagnetic Weyl semimetal layer 500 .

Through step S310, an external magnetic field is used to initialize, so that the magnetic moment directions of the first topological antiferromagnetic Weyl semimetal layer 300 and the second topological antiferromagnetic Weyl semimetal layer 500 are the same, that is, the magnetic moment directions of the two layers are arranged in parallel , are perpendicular to the surface of the second topological antiferromagnetic Weyl semimetal layer 500

By applying a small constant current source I between the first topological antiferromagnetic Weyl semi-metal 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.

Through step S320, by applying a positive pulse voltage U (generating a positive pulse current) to the first topological antiferromagnetic Weyl semimetal layer 300, the topological antiferromagnetic state in the first topological antiferromagnetic Weyl semimetal layer 300 is generated by 180° Flip to obtain the information writing/reading schematic diagram of the V-V type magnetic random access memory cell shown in Figure 5B after applying a pulse voltage (generating a pulse current). At this time, by reading the first topological antiferromagnetic Weyl semi-metal layer The voltage V between the protection layer and the jump of the tunneling resistance can be detected, and the magnetic random memory unit can write a signal of "1".

After inputting a negative pulse voltage U (to generate a negative pulse current) in the topological antiferromagnetic Weyl semimetal layer 300, the topological antiferromagnetic state in the topological antiferromagnetic Weyl semimetal layer 300 recovers, resulting in a jump in the tunneling resistance . By reading the change of the V value and detecting the change of the tunnel resistance, the magnetic random memory unit writes a signal of "0".

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 in the text of the specification, implementations that are not shown or described are forms known to those of ordinary skill in the art, and are not described in detail. In addition, the above definitions of each element and method are not limited to the various specific structures, shapes or methods mentioned in the embodiments, and those skilled in the art can easily modify or replace them.

Based on the above description, those skilled in the art should have a clear understanding of the magnetic random access memory unit made based on the topological antiferromagnetic Weyl semimetal in the embodiments of the present disclosure, its preparation method and usage method.

To sum up, this disclosure no longer uses conventional magnetic random access memory cells based on ferromagnetic materials, and proposes to use topological antiferromagnetic Weyl semimetals as information carrier materials for spin-orbit moment devices, through the topological antiferromagnetic Weyl semimetal layer The current-induced intrinsic spin-orbit torque effect controls the topological antiferromagnetic state in the topological antiferromagnetic Weyl semimetal layer to produce a 180° flip, thereby realizing the magnetic random memory unit based on the topological antiferromagnetic Weyl semimetal material.

Information devices based on topological antiferromagnetic Weyl semimetal materials have the advantages of no external magnetic field dependence, high stability, fast speed, low power consumption, and long service life. Brain computing and other fields.

And the shape and size of each component in the figure do not reflect the actual size and proportion, but only illustrate the content of the embodiment of the present disclosure. Furthermore, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Unless known to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that can vary depending upon the desired properties obtained from the teachings of the present disclosure. Specifically, all numbers used in the specification and claims to represent the content of components, reaction conditions, etc., should be understood to be modified by the term "about" in all cases. In general, the expressed meaning is meant to include a variation of ±10% in some embodiments, a variation of ±5% in some embodiments, a variation of ±1% in some embodiments, a variation of ±1% in some embodiments, and a variation of ±1% in some embodiments ±0.5% variation in the example.

Furthermore, the word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

Words such as "first", "second", "third" and the like used in the description and claims to modify the corresponding elements do not in themselves mean that the elements have any ordinal numbers, nor The use of these ordinal numbers to represent the sequence of an element with respect to another element, or the order of manufacturing methods, is only used to clearly distinguish one element with a certain designation from another element with the same designation.

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

Claims (10)

1. A magnetic random access memory cell, comprising:

a substrate;

a buffer layer formed on the substrate;

the first topological antiferromagnetic Weyl half metal layer is formed on the buffer layer and used for driving the topological antiferromagnetic state in the first topological antiferromagnetic Weyl half metal layer to generate 180-degree turnover through applying current;

a tunneling insulating layer formed on the first topological antiferromagnetic Weyl semi-metal layer;

a second topological antiferromagnetic Weyl half metal layer formed on said tunneling insulating layer;

a protective layer formed on said second said topological antiferromagnetic Weyl half metal layer.

2. The MRAM cell of claim 1, wherein the MRAM cell is configured to store a magnetic fieldCharacterized in that said first and second topological antiferromagnetic Weyl half-metal layers are made of a non-linear antiferromagnetic material comprising Mn ₃ Sn、Mn ₃ Ge、Mn ₃ Ni、Mn ₃ Cu、Mn ₃ Zn、Mn ₃ Ga、Mn ₃ Pd、Mn ₃ In、Mn ₃ Ir、Mn ₃ One or a combination of more of Pt.

3. The MRAM cell of claim 1, wherein the easy magnetization direction of the first topological antiferromagnetic Weyl half metal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl half metal layer when the easy magnetization direction of the second topological antiferromagnetic Weyl half metal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl half metal layer.

4. The MRAM cell of claim 1, wherein when the easy magnetization direction of the second topological antiferromagnetic Weyl half metal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl half metal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl half metal layer is parallel to the surface direction of the second topological antiferromagnetic Weyl half metal layer.

5. The MRAM cell of claim 1, wherein the tunneling insulating layer has a thickness of 0.5 to 3nm.

6. A method of fabricating a magnetic random access memory cell, comprising:

growing a buffer layer on a substrate;

growing a first topological antiferromagnetic Weyl semi-metal layer on the buffer layer;

growing a tunneling insulating layer on the first topological antiferromagnetic Weyl semi-metal layer;

growing a second topological antiferromagnetic Weyl semi-metal layer on the tunneling insulating layer;

a protective layer is grown on the second topological antiferromagnetic Weyl half-metal layer.

7. The method of claim 6, wherein the step of forming the magnetic random access memory cell,

and when the first topological antiferromagnetic Weyl semi-metal layer and the second topological antiferromagnetic Weyl semi-metal layer are annealed, controlling the easy magnetization directions of the first topological antiferromagnetic Weyl semi-metal layer and the second topological antiferromagnetic Weyl semi-metal layer by using an external magnetic field.

8. The method of claim 7, wherein the controlling the easy magnetization direction of the first and second topological antiferromagnetic Weyl half metal layers comprises:

when the easy magnetization direction of the second topological antiferromagnetic Weyl half metal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl half metal layer, the easy magnetization direction of the first topological antiferromagnetic Weyl half metal layer is perpendicular to the surface direction of the second topological antiferromagnetic Weyl half metal layer;

when the direction of easy magnetization of said second topological antiferromagnetic Weyl half metal layer is parallel to the surface direction of said second topological antiferromagnetic Weyl half metal layer, the direction of easy magnetization of said first topological antiferromagnetic Weyl half metal layer is parallel to the surface direction of said second topological antiferromagnetic Weyl half metal layer.

9. A method of using a magnetic random access memory cell, the magnetic random access memory cell as claimed in claims 1 to 5, comprising:

initializing by using an external magnetic field, so that the magnetic moment directions of the first topological antiferromagnetic Weyl semi-metal layer and the second topological antiferromagnetic Weyl semi-metal layer are the same;

the 180 ° flip of the topological antiferromagnet state in the first topological antiferromagnet Weyl half metal layer is caused by applying a pulsed voltage to the first topological antiferromagnet Weyl half metal layer.

10. The method of using a magnetic random access memory cell of claim 9, comprising:

and reading the voltage between the first topological antiferromagnet Weyl semi-metal layer and the protective layer to obtain the tunneling resistance change of the magnetic random access memory cell as output information.

Images