Unidirectional track magnetoresistive material, track moment device and data reading and writing method thereof

Abstract

A unidirectional track magnetoresistance material, a track moment device and a data reading and writing method thereof, which relate to the field of track moment electronics, wherein the unidirectional track magnetoresistance material comprises a superimposed track moment layer and a magnetic layer, wherein the track moment layer and the magnetic layer are configured to form a heterojunction having a unidirectional track magnetoresistance; the material of the track moment layer comprises any one or more of a light metal and a light metal oxide having a track moment effect. The unidirectional track magnetoresistance material of the present application can exhibit a unidirectional track magnetoresistance at room temperature, which is conducive to promoting the wide application of track moment devices.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of orbital moment electronics, and in particular to a unidirectional orbital magnetoresistive material, an orbital moment device, and a data reading and writing method thereof. Background Art

[0002] Spin Orbit Torque (SOT) devices are semiconductor devices based on the spin-orbit effect. They work by generating spin currents when charges pass through the spin-orbit material, which in turn controls the magnetic moment of the magnetic layer. Spin-orbit torque devices rely on magnetic tunnel junctions (MTJs) for data reading, but the preparation conditions of MTJs are harsh, difficult, and costly. Summary of the invention

[0003] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of protection of this application.

[0004] An embodiment of the present application provides a unidirectional orbital magnetoresistance material, comprising a superimposed orbital moment layer and a magnetic layer, wherein the orbital moment layer and the magnetic layer are configured to form a heterojunction with unidirectional orbital magnetoresistance; the material of the orbital moment layer comprises any one or more of light metals and light metal oxides having an orbital moment effect.

[0005] In some embodiments of the present application, the light metal may be selected from any one or more of titanium, copper, aluminum, gallium, ruthenium, molybdenum, vanadium, iridium and silver.

[0006] In some embodiments of the present application, the light metal oxide may be selected from any one or more of titanium oxide, aluminum oxide, ruthenium oxide, vanadium oxide, silver oxide and chromium oxide.

[0007] In some embodiments of the present application, the magnetic layer may be a ferromagnetic layer, a ferrimagnetic layer or an antiferromagnetic layer.

[0008] In some embodiments of the present application, the material of the magnetic layer may include any one or more of cobalt, nickel, iron, boron and manganese elements.

[0009] In some embodiments of the present application, the material of the orbital moment layer may be titanium, and the material of the magnetic layer may be cobalt.

[0010] In some embodiments of the present application, the thickness of a single-layer track moment layer may not exceed 100 nm.

[0011] In some embodiments of the present application, the unidirectional track magnetoresistance material exhibits unidirectional track magnetoresistance in an environment not exceeding 1000 Kelvin.

[0012] The embodiment of the present application also provides a track torque device, including the unidirectional track magnetoresistive material provided in the embodiment of the present application, the track torque layer can be one or more layers, and the magnetic layer can be one or more layers.

[0013] In some embodiments of the present application, the track-torque device does not include a magnetic tunnel junction.

[0014] In some embodiments of the present application, the track moment layer may be a multi-layer, and / or the magnetic layer may be a multi-layer, and the multi-layer track moment layer and / or magnetic layer are alternately arranged.

[0015] In some embodiments of the present application, the orbital torque device may further include any one or more of a spin Hall layer and an enhancement layer.

[0016] In some embodiments of the present application, the spin Hall layer may be disposed on a side of the magnetic layer away from the orbital moment layer.

[0017] In some embodiments of the present application, the enhancement layer may be disposed between the magnetic layer and the orbital moment layer.

[0018] In some embodiments of the present application, the track torque device may be a storage device, a logic device, a storage-computing integrated device, or a memristor device.

[0019] The present application also provides a method for reading and writing data of a track moment device, comprising:

[0020] Using the orbital current generated by the orbital moment layer to flip the magnetization direction of the magnetic layer to write data;

[0021] Data reading is performed using second harmonic resistance.

[0022] The unidirectional track magnetoresistance material of the embodiment of the present application can exhibit unidirectional track magnetoresistance under room temperature conditions, which is conducive to promoting the widespread application of track torque devices.

[0023] Other features and advantages of the present application will be described in the following description, and partly become clearer from the description, or understood by practicing the present application. Other advantages of the present application can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0025] Figure 1 A schematic structural diagram of a track moment device of an exemplary embodiment of the present application;

[0026] Figure 2A To test the magnetoresistance R of the orbital torque device at room temperature xx Schematic diagram of circuit connection used when the trend of magnetic field direction changes;

[0027] Figure 2B for Figure 1 The magnetoresistance R of the orbital moment device shown at room temperature is xx Trend diagram of changes with magnetic field direction;

[0028] Figure 3A A schematic diagram of the circuit connection used to test the variation trend of the Hall magnetoresistance of the orbital torque device with the direction of the magnetic field at room temperature;

[0029] Figure 3B for Figure 1 The Hall magnetoresistance of the orbital torque device shown in the figure changes with the direction of the magnetic field at room temperature;

[0030] Figure 4 It is a schematic structural diagram of a track moment device of an exemplary embodiment of the present application;

[0031] Figure 5 It is a schematic structural diagram of a track moment device of an exemplary embodiment of the present application;

[0032] Figure 6 It is a schematic structural diagram of a track moment device of an exemplary embodiment of the present application;

[0033] Figure 7 It is a schematic structural diagram of a track moment device of an exemplary embodiment of the present application;

[0034] Figure 8 This is a graph showing the relationship between the magnitude of the unidirectional track magnetic resistance and the thickness of the track moment layer. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present application more clear, the embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0036] The embodiments of the present application are not necessarily limited to the dimensions shown in the drawings, and the shapes and sizes of the components in the drawings do not reflect the true proportions. In addition, the drawings schematically show ideal examples, and the embodiments of the present application are not limited to the shapes or values ​​shown in the drawings.

[0037] In the description of this application, "film (or thin film)" and "layer" can be interchanged. For example, "track moment layer" can sometimes be replaced by "track moment film (or thin film)". Similarly, "magnetic film" can sometimes be replaced by "magnetic layer".

[0038] Orbital moment is a new type of moment different from spin-orbit moment. The working mode of orbital moment device is that after the charge flow passes through the orbital moment material (for example, metal material film), due to the existence of orbital moment, it can indirectly stimulate the spin flow to flip the magnetic moment of the magnetic material (for example, magnetic material film), or it can directly flip the magnetic material based on the orbital flow generated by the orbital moment, so as to realize the writing of data.

[0039] In order to read data, the current orbital torque memory usually uses an orbital torque layer and a magnetic tunnel junction to form a storage unit, relying on a magnetic tunnel junction (MTJ) to read data. Therefore, the current orbital torque memory faces all the problems existing in spinorbit torque magnetic random access memory (SOT-MRAM), such as harsh MTJ preparation conditions, high difficulty and high cost. In addition, the orbital torque efficiency is low, so the current orbital torque device has no obvious advantage over SOT-MRAM.

[0040] Unidirectional orbital magnetoresistive material is a new type of orbital moment material developed in recent years. When the heterojunction composed of orbital moment material and magnetic material has the unidirectional magnetoresistive property, the data reading function can be realized. Therefore, when the heterojunction composed of orbital moment material and magnetic material has the unidirectional magnetoresistive property, it can meet the two characteristics that the memory needs to meet: data writing and reading functions, and obtain a unidirectional magnetoresistive orbital moment memory.

[0041] Compared with spin orbit torque magnetic random access memory (SOT-MRAM), unidirectional magnetoresistive orbit torque memory has the following advantages:

[0042] (1) Can significantly reduce process costs

[0043] The track torque device of the embodiment of the present application does not rely on a magnetic tunnel junction (MTJ) for data reading, so there is no need to set up an MTJ, which can avoid the harsh conditions during MTJ preparation and reduce the difficulty and cost of preparation.

[0044] (2) The storage unit has two-end interfaces, which can greatly reduce the difficulty of integration

[0045] The storage cell of SOT-MRAM is a three-terminal interface, while the storage cell of the track torque device of the embodiment of the present application can be a two-terminal interface. Reducing the number of interfaces of the storage cell can not only greatly reduce the circuit complexity of the integration process, but also effectively improve the storage density per unit area.

[0046] However, the current unidirectional magnetoresistive orbital torque memory still has some defects.

[0047] (1) Defects of relying on external magnetic field to write data

[0048] At present, the research based on unidirectional orbital magnetoresistance mainly focuses on data writing with the assistance of external magnetic field, which seriously restricts the realization of unidirectional magnetoresistance orbital moment memory and also hinders the realization of large-scale integration technology.

[0049] (2) The unidirectional magnetoresistance in low temperature environments hinders widespread application in reality

[0050] Although unidirectional magnetoresistance has been discovered for nearly a decade, the discovery is mainly concentrated in the heterojunction formed by spin Hall materials / magnetic materials (such as topological insulator / magnetic material heterojunction, heavy metal / antiferromagnetic material heterojunction and heavy metal / ferromagnetic material heterojunction, etc.). However, the magnetoresistance of these heterojunctions is generally unidirectional only at low temperatures, which is still far from practical application.

[0051] An embodiment of the present application provides a unidirectional orbital magnetoresistance material, comprising a superimposed orbital moment layer and a magnetic layer, wherein the orbital moment layer and the magnetic layer are configured to form a heterojunction with unidirectional orbital magnetoresistance; the material of the orbital moment layer comprises any one or more of light metals and light metal oxides having an orbital moment effect.

[0052] The unidirectional track magnetoresistance material of the embodiment of the present application can exhibit unidirectional track magnetoresistance under room temperature conditions, which is conducive to promoting the widespread application of track torque devices.

[0053] In addition, the unidirectional orbital magnetoresistance material of the embodiment of the present application has an orbital moment effect and a unidirectional orbital magnetoresistance effect. The orbital current generated by the orbital moment can be used to flip the magnetization direction of the magnetic layer to achieve data writing, thereby achieving pure electrical writing and avoiding the defect of relying on an external magnetic field to achieve data writing; the unidirectional orbital magnetoresistance material of the embodiment of the present application can utilize the unidirectional orbital magnetoresistance effect to achieve data reading, so there is no need to set up a magnetic tunnel junction (MTJ), reducing the difficulty and cost of device preparation.

[0054] In some embodiments of the present application, the light metal may be selected from any one or more of titanium, copper, aluminum, gallium, ruthenium, molybdenum, vanadium, iridium and silver.

[0055] In some embodiments of the present application, the light metal oxide may be selected from any one or more of titanium oxide, aluminum oxide, ruthenium oxide, vanadium oxide, silver oxide and chromium oxide.

[0056] In some embodiments of the present application, the magnetic layer may be a ferromagnetic layer, a ferrimagnetic layer or an antiferromagnetic layer.

[0057] In some embodiments of the present application, the material of the magnetic layer may include any one or more of cobalt, nickel, iron, boron and manganese. For example, the material of the magnetic layer may be cobalt, nickel, iron, cobalt iron boron, etc.

[0058] In some embodiments of the present application, the material of the magnetic layer may include in-plane magnetic material and / or perpendicular magnetic material.

[0059] In some embodiments of the present application, the material of the orbital moment layer may be titanium, and the material of the magnetic layer may be cobalt.

[0060] In some embodiments of the present application, the thickness of the single-layer orbital moment layer may not exceed 100nm, for example, it may be 3nm, 5nm, 8nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm or 100nm. For another example, the thickness of the single-layer orbital moment layer may not exceed 50nm.

[0061] In some embodiments of the present application, the unidirectional track magnetoresistance material can exhibit unidirectional track magnetoresistance in an environment not exceeding 1000 Kelvin (K), for example, can exhibit unidirectional track magnetoresistance at room temperature (about 290° C. to 305° C.).

[0062] The embodiment of the present application also provides a track torque device, including the unidirectional track magnetoresistive material provided in the embodiment of the present application, the track torque layer can be one or more layers, and the magnetic layer can be one or more layers.

[0063] The unidirectional orbital magnetoresistance material of the orbital torque device in the embodiment of the present application can exhibit unidirectional orbital magnetoresistance at room temperature, which is conducive to promoting the widespread application of the orbital torque device.

[0064] In addition, the orbital torque device of the embodiment of the present application is a unidirectional magnetoresistive orbital torque device that reads and writes in a purely electrical manner. Among them, the unidirectional orbital magnetoresistive material of the orbital torque device of the embodiment of the present application has an orbital torque effect and a unidirectional orbital magnetoresistive effect, and the orbital current generated by the orbital torque can be used to flip the magnetization direction of the magnetic layer to achieve data writing, thereby achieving pure electrical writing, avoiding the defect of relying on an external magnetic field to achieve data writing; moreover, the orbital torque device of the embodiment of the present application can use the unidirectional orbital magnetoresistive effect to achieve data reading, thereby achieving pure electrical reading, so there is no need to set up a magnetic tunnel junction (MTJ), reducing the difficulty and cost of device preparation.

[0065] In some embodiments of the present application, the track-torque device does not include a magnetic tunnel junction.

[0066] Figure 1 FIG. 1 is a schematic diagram of the structure of a track torque device of an exemplary embodiment of the present application. Figure 1 As shown, the track torque device includes a substrate 10 , a track torque layer 20 disposed on one side of the substrate 10 , and a magnetic layer 30 disposed on a side of the track torque layer 20 away from the substrate 10 .

[0067] The track moment layer 20 and the magnetic layer 30 are both one layer. The material of the substrate 10 is silicon (Si(111)); the material of the track moment layer 20 is titanium (Ti), and the thickness of the track moment layer 20 is 3nm; the material of the magnetic layer 30 is cobalt (Co), and the thickness of the magnetic layer 30 is 6nm.

[0068] Figure 2A To test the magnetoresistance R of the orbital torque device at room temperature xx Schematic diagram of circuit connection used when the trend of magnetic field direction changes; Figure 2B for Figure 1 The magnetoresistance R of the orbital moment device shown at room temperature is xx The trend graph of changes with the direction of the magnetic field, the ordinate on the left is the first-order data, and the ordinate on the right is the second harmonic data. Figure 3A A schematic diagram of the circuit connection used to test the variation trend of the Hall magnetoresistance of the orbital torque device with the direction of the magnetic field at room temperature; Figure 3B for Figure 1 The Hall magnetoresistance of the orbital torque device at room temperature is shown as a function of the magnetic field direction. The ordinate on the left is the first-order data, and the ordinate on the right is the second harmonic data.

[0069] according to Figure 2B and Figure 3B It can be seen that the magnetic resistance of the second harmonic in the directions of 90° and 270° has obvious high and low states, indicating that the orbital torque device of Example 1 of the present application has a unidirectional orbital magnetic resistance.

[0070] In some embodiments of the present application, the orbital moment layer may be one or more layers, and the magnetic layer may be one or more layers.

[0071] Figures 4 to 7 It is a schematic diagram of the structure of the track torque device of the exemplary embodiment of the present application.

[0072] In such Figure 4 In the track torque device shown, there are two track torque layers 20 and one magnetic layer 30 , and one magnetic layer 30 is arranged between the two track torque layers 20 , forming an alternating stacking structure of track torque layer 20 / magnetic layer 30 / track torque layer 20 on the substrate 10 .

[0073] In such Figure 5In the track torque device shown, the track torque layer 20 is composed of two layers, and the magnetic layer 30 is composed of two layers. The track torque layer 20 and the magnetic layer 30 are alternately arranged on the substrate 10 in sequence.

[0074] In some embodiments of the present application, the orbital torque device may further include a spin Hall layer. Figure 6 As shown, the orbital moment device may include a substrate 10, an orbital moment layer 20 disposed on one side of the substrate 10, a magnetic layer 30 disposed on a side of the orbital moment layer 20 away from the substrate 10, and a spin Hall layer 40 disposed on a side of the magnetic layer 30 away from the substrate 10.

[0075] In some embodiments of the present application, the track torque device may further include an enhancement layer 50 for enhancing the unidirectional track magnetoresistance effect. Figure 7 As shown, the track moment device may include a substrate 10, a track moment layer 20 disposed on one side of the substrate 10, a magnetic layer 30 disposed on a side of the track moment layer 20 away from the substrate 10, and an enhancement layer 50 disposed on a side of the magnetic layer 30 away from the substrate 10.

[0076] Figure 8 This is a graph showing the relationship between the magnitude of the unidirectional track magnetic resistance and the thickness of the track moment layer.

[0077] like Figure 8 As shown in the figure, as the thickness of the track moment layer gradually increases, the unidirectional magnetic resistance of the device also increases. According to the test, the track moment layer with a thickness ranging from 0 to 100nm conforms to this law.

[0078] In some embodiments of the present application, the track moment layer may be a multi-layer, and / or the magnetic layer may be a multi-layer, and the multi-layer track moment layer and / or magnetic layer are alternately arranged.

[0079] In some embodiments of the present application, the orbital torque device may further include any one or more of a spin Hall layer and an enhancement layer.

[0080] In some embodiments of the present application, the spin Hall layer may be disposed on a side of the magnetic layer away from the orbital moment layer.

[0081] In some embodiments of the present application, the enhancement layer may be disposed between the magnetic layer and the orbital moment layer.

[0082] In some embodiments of the present application, the track torque device may be a storage device, a logic device, a storage-computing integrated device, or a memristor device.

[0083] The present application also provides a method for reading and writing data of a track moment device, comprising:

[0084] Using the orbital current generated by the orbital moment layer to flip the magnetization direction of the magnetic layer to write data;

[0085] Data reading is performed using second harmonic resistance.

[0086] The data reading and writing method of the orbital torque device of the embodiment of the present application can apply a large current to the orbital torque layer, stimulate the orbital current to flip the magnetization direction of the magnetic layer to realize the writing function, and then read the second harmonic resistance based on a small AC current to realize the data reading function.

[0087] The data reading and writing method of the orbital torque device of the embodiment of the present application effectively integrates the orbital torque reversal magnetic torque technology and the second harmonic reading technology, so that the data reading function and the data writing function in the pure electrical mode can still be realized in the absence of a magnetic tunnel junction.

[0088] Although the embodiments disclosed in this application are as above, the contents described are only embodiments adopted to facilitate understanding of this application and are not intended to limit this application. Any technician in the field to which this application belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in this application, but the scope of protection of this application shall still be based on the scope defined in the attached claims.

Claims

1. A unidirectional track magnetoresistive material for track moment devices, characterized in that: The invention comprises a superimposed orbital moment layer and a magnetic layer, wherein the orbital moment layer and the magnetic layer are configured to form a heterojunction with unidirectional orbital magnetic resistance; the material of the orbital moment layer comprises any one or more of a light metal and a light metal oxide having an orbital moment effect; Wherein, the light metal is selected from any one or more of titanium, aluminum, gallium, ruthenium, molybdenum, vanadium, iridium and silver; The light metal oxide is selected from any one or more of titanium oxide, aluminum oxide, ruthenium oxide, vanadium oxide, silver oxide and chromium oxide.

2. The unidirectional track magnetoresistive material according to claim 1, characterized in that: The magnetic layer is a ferromagnetic layer, a ferrimagnetic layer or an antiferromagnetic layer.

3. The unidirectional track magnetoresistive material according to claim 2, characterized in that: The material of the magnetic layer includes any one or more of cobalt, nickel, iron, boron and manganese.

4. The unidirectional track magnetoresistive material according to claim 1, characterized in that: The material of the orbital moment layer is titanium, and the material of the magnetic layer is cobalt.

5. The unidirectional track magnetoresistive material according to any one of claims 1 to 4, characterized in that: The thickness of a single-layer orbital moment layer does not exceed 100 nm.

6. The unidirectional track magnetoresistive material according to any one of claims 1 to 4, characterized in that: It exhibits unidirectional orbital magnetoresistance in an environment not exceeding 1000 Kelvin.

7. A track moment device, characterized in that: It comprises the unidirectional track magnetoresistive material according to any one of claims 1 to 6, wherein the track moment layer is one or more layers, and the magnetic layer is one or more layers.

8. The track moment device according to claim 7, characterized in that: Magnetic tunnel junctions are not included.

9. The track moment device according to claim 8, characterized in that: The track moment layer is multi-layered, the magnetic layer is multi-layered, and the multi-layer track moment layer and the magnetic layer are alternately arranged; and / or, The orbital moment device also includes any one or more of a spin Hall layer and an enhancement layer for enhancing the unidirectional orbital magnetoresistance effect; the spin Hall layer is arranged on a side of the magnetic layer away from the orbital moment layer, and / or the enhancement layer is arranged between the magnetic layer and the orbital moment layer.

10. The track torque device according to any one of claims 7 to 9, characterized in that: It is a storage device, a logic device, a storage-computing integrated device or a memristor device.

11. A track moment device, characterized in that: It includes a unidirectional track magnetoresistance material, which includes a superimposed track moment layer and a magnetic layer, and the track moment layer and the magnetic layer are configured to form a heterojunction with unidirectional track magnetoresistance; the track moment layer is one or more layers, and the magnetic layer is one or more layers; the material of the track moment layer includes copper; the track moment device does not include a magnetic tunnel junction and has a purely electrical data reading and data writing function.

12. A method for reading and writing data of a track torque device according to any one of claims 7 to 11, characterized in that: include: The orbital current generated by the orbital moment layer is used to flip the magnetization direction of the magnetic layer to write data; Data reading is performed using second harmonic resistance.

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