A magnetic nano-multi-ring storage device, a preparation method thereof, and an application thereof

Abstract

The present invention provides a magnetic nano multi-ring storage device, a preparation method thereof, and an application. The magnetic nano multi-ring storage device includes: a substrate; and a unit attached to the substrate; wherein the unit is composed of nano-rings with overlapping ring edges or ring edges in contact connection. Since the device with overlapping ring edges has a relatively large exchange coupling strength, its hysteresis loop exhibits a three-step magnetization reversal process and a complex magnetic domain state; the hysteresis loops of the devices with ring edges in contact connection all show a two-step magnetization reversal behavior, and the magnetic domain state of the second plateau on its hysteresis loop is a vortex state; the chirality of the multi-nano-ring magnetic structures with overlapping ring edges and ring edges in contact connection is controllable. The present invention provides a method for regulating the chirality of magnetic nano-rings, and provides a new means for artificial magnetic nano-structure storage.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic devices, and particularly relates to a magnetic nano-multi-ring storage device, a preparation method thereof, and an application thereof. Background Art

[0002] The vortex state of a magnetic nano-ring device is a special magnetic domain configuration, which is characterized by a closed magnetic flux and a low stray field. In this state, the magnetic domains are distributed 360° along the nano-ring, enabling the internal magnetic field to effectively cancel the magnetic interference from the external environment. These characteristics have shown great advantages in the design and manufacture of magnetic random access memories, magnetic sensors, and magnetic switching devices. For example, a vortex-state magnetic storage unit with a nano-unit structure disclosed in Chinese Patent CN 104575583A can maintain a stable vortex state at a smaller size and can complete rapid magnetization reversal under the control of a magnetic field. A magnetic field sensor using the giant magnetoresistance effect of ferromagnetic nano-rings disclosed in Chinese Patent CN 101363903B detects the change of an external magnetic field by using the huge change in resistance of a ferromagnetic nano-ring under the action of an external magnetic field, and the sensitivity at the magnetic field transition point can reach 2% - 10% / Oe or higher.

[0003] During the read and write processes of a magnetic random access memory device, the storage units of data can be defined as "0" and "1" respectively according to different chiralities of the vortex state. However, the initial chirality of a single nano-ring device is often unpredictable, which directly affects the accurate recording and reading of data. Therefore, achieving precise control of the chirality of a nano-ring device has become an extremely crucial and difficult task. Summary of the Invention

[0004] The present invention provides a magnetic nano-multi-ring storage device, a preparation method thereof, and an application thereof, so as to provide more stable, new, and modifiable magnetic domain states and provide more choices for the compilation and decoding of magnetic recording writes.

[0005] This specification discloses a magnetic nano-multi-ring storage device, including:

[0006] A substrate;

[0007] A unit attached to the substrate;

[0008] Wherein, the unit is composed of a plurality of nano-rings with overlapping or contacting ring edges.

[0009] In this specification, the material of the substrate is an insulating material.

[0010] In this specification, the nano-ring is composed of a soft magnetic material thin film.

[0011] In this specification, the outer diameter of the nano-ring is d, the ring width is w, and the thickness is t, where w = d / 4, d ∈ (100 nm, 1.5 μm), and t ∈ (20 nm, 80 nm).

[0012] In this specification, the arrangement of multiple nano-rings is as follows: with one nano-ring as the center, nano-rings are added outward along the horizontal and vertical axes of the ring plane; when there are three nano-rings, the connecting lines of the centers of the three nano-rings form a right triangle, and the two right sides are along the horizontal and vertical directions respectively; when there are four nano-rings, the outermost edges of the connecting lines of the centers of the four nano-rings enclose an isosceles triangle, and the centers of three of the nano-rings are on the same straight line, and this straight line is along the horizontal or vertical axis direction; when there are five nano-rings, the outermost edges of the connecting lines of the centers of the five nano-rings enclose a square, and the diagonals of the square are along the horizontal and vertical axis directions respectively, and the intersection point of the diagonals is the center of the central nano-ring.

[0013] In this specification, the overlapping of the ring edges of multiple nano-rings is as follows: the connections between the rings overlap with each other, the outer diameter of one ring is tangent to the inner diameter of another ring, and the distance between the centers of adjacent rings is the difference between the outer diameter of the nano-ring and the ring width of the nano-ring.

[0014] In this specification, the contact connection of the ring edges of multiple nano-rings is as follows: the distance between the centers of adjacent rings is l, and l ∈ (the difference between the outer diameter of the nano-ring and the ring width of the nano-ring, the outer diameter of the nano-ring).

[0015] This specification also discloses a preparation method of a magnetic nano multi-ring storage device, including:

[0016] Using one of deep ultraviolet lithography technology, extreme ultraviolet exposure technology, electron beam exposure technology, and nanoimprint technology to form the required template on the substrate material;

[0017] Using one of magnetron sputtering technology, electron beam evaporation technology, molecular beam epitaxy technology, and pulsed laser deposition technology to form a nano-ring structure on the template to prepare the magnetic nano multi-ring storage device described in any one of the above.

[0018] In this specification, the substrate material is any one of silicon wafers, silicon oxide wafers, ITO glass substrates, FTO glass substrates, K9 glass substrates, quartz glass substrates, sapphire single crystal wafers, and gallium arsenide substrates.

[0019] This specification also discloses an application of a magnetic nano multi-ring storage device, using the magnetic nano multi-ring storage device described in any one of the above to prepare a magnetic random access memory, a magnetic nano switch device, a magnetic spin device, and a magnetic sensor.

[0020] This specification can at least achieve the following beneficial effects:

[0021] Due to the large exchange coupling strength of the ring-edge overlapping type device, its hysteresis loop exhibits a three-step magnetization reversal process and complex magnetic domain states; the hysteresis loops of the ring-edge contact-connected type devices all show a two-step magnetization reversal behavior, and the magnetic domain state at the second plateau on the hysteresis loop is a vortex state; the chirality of the ring-edge overlapping type and ring-edge contact-connected type multi-nanoring magnetic structures is controllable. The magnetic nano multi-ring storage device of the present invention provides a method for regulating the chirality of magnetic nanorings and provides a new means for artificial magnetic nanostructure storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0023] Figure 1a Schematic diagrams of the ring-edge overlapping type magnetic nano multi-ring storage device involved in the present invention, which are schematic diagrams of 3 nanorings, 4 nanorings, and 5 nanorings from left to right in sequence.

[0024] Figure 1b Schematic diagrams of the ring-edge contact-connected type magnetic nano multi-ring storage device involved in the present invention, which are schematic diagrams of 3 nanorings, 4 nanorings, and 5 nanorings from left to right in sequence.

[0025] Figure 2a Hysteresis loop of the ring-edge overlapping type 3-nanoring magnetic nano multi-ring storage device involved in the present invention, as well as magnetic domain state diagrams and micromagnetic simulation diagrams at corresponding steps.

[0026] Figure 2b Hysteresis loop of the ring-edge overlapping type 4-nanoring magnetic nano multi-ring storage device involved in the present invention, as well as magnetic domain state diagrams and micromagnetic simulation diagrams at corresponding steps.

[0027] Figure 2c Hysteresis loop of the ring-edge overlapping type 5-nanoring magnetic nano multi-ring storage device involved in the present invention, as well as magnetic domain state diagrams and micromagnetic simulation diagrams at corresponding steps.

[0028] Figure 3a Hysteresis loop of the ring-edge contact-connected type 3-nanoring magnetic nano multi-ring storage device involved in the present invention, as well as magnetic domain state diagrams and micromagnetic simulation diagrams at corresponding steps.

[0029] Figure 3bThe hysteresis loop of the magnetic nano-multi-ring memory device with 4 nano-rings of the ring-edge contact connection type involved in the present invention, as well as the magnetic domain state diagrams and micromagnetic simulation diagrams at the corresponding steps.

[0030] Figure 3c The hysteresis loop of the magnetic nano-multi-ring memory device with 5 nano-rings of the ring-edge contact connection type involved in the present invention, as well as the magnetic domain state diagrams and micromagnetic simulation diagrams at the corresponding steps.

[0031] Figure 4 The schematic diagram of the signal writing circuit of the magnetic nano-multi-ring memory device involved in the present invention for a reading and writing device.

[0032] Figure 5 The schematic diagram of the signal reading circuit of the magnetic nano-multi-ring memory device involved in the present invention for a reading and writing device. Detailed implementation manners

[0033] In the following text, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0034] The following disclosure provides many different implementation manners or examples for implementing different structures of the embodiments of the present invention. To simplify the disclosure of the embodiments of the present invention, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the embodiments of the present invention. In addition, the embodiments of the present invention may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various implementation manners and / or settings discussed.

[0035] The embodiments of the present invention will be described in detail below with reference to the drawings.

[0036] The technical concept of the present invention is as follows:

[0037] In the reports on magnetic structures composed of two rings, for the two types of double rings with strong exchange coupling due to physical contact, both show complex three-step magnetization reversal and form a vortex state. The vortex chiralities of the two rings constituting the double-ring structure are correlated with each other, but the stability of the intermediate magnetic domain state is poor and not suitable for applications. For the double-ring structure without physical contact, the magnetization reversal process shows a two-step reversal similar to that of a single ring, with a stable vortex state, but its chirality cannot be controlled. In addition, in the reports on double-ring arrays, it is found that the nucleation of vortex states, twisted states, onion states, and a new magnetic domain state named heart state is related to the thickness of the structure and the distance between the double rings. It is inferred that the formation of physical contact between the rings significantly increases their exchange coupling strength, thereby changing the magnetization reversal process and ultimately having a profound impact on the generation, stability, and chirality control of the vortex state. Therefore, adjusting the number and geometric configuration of the nanorings with physical contact to achieve the chirality control of the vortex state has become a new idea for the development of magnetic nanoring devices, but there is still little research in this area.

[0038] On the other hand, if the magnetic nanoring has more stable magnetic domain states, based on the definition of binary, more choices can be obtained. For example, in the overlapping nanodouble rings, during the magnetization reversal process, the formed intermediate stable state is a vortex state with the same chirality, and there are domain walls in the overlapping region of the two rings. Such an intermediate state is different from the pure vortex state and onion state and is a new type of stable magnetic domain state, providing more diverse choices for the read-write compilation of magnetic random access memories. Therefore, studying the magnetic interaction between nanorings to obtain more stable magnetic domain states and realizing the chirality control of magnetic nanorings is very important for applications such as magnetic nanoswitch devices or magnetic storage devices, which will result in more flexible and rich switch information or read-write information compilation.

[0039] Thus, as Figure 1a and Figure 1b shown, this specification discloses a magnetic nano multi-ring storage device, including:

[0040] A substrate;

[0041] A unit attached to the substrate;

[0042] Wherein, the unit is composed of nanorings with overlapping or contacting ring edges.

[0043] In this specification, the material of the substrate is an insulating material.

[0044] In this specification, the nanoring is composed of a soft magnetic material thin film.

[0045] In this specification, the outer diameter of the nanoring is d, the ring width is w, and the thickness is t, where w = d / 4, d ∈ (100 nm, 1.5 μm), and t ∈ (20 nm, 80 nm).

[0046] In some embodiments, the arrangement of multiple nanorings is as follows: with one nanoring as the center, nanorings are added outward along the horizontal and vertical axes of the ring plane; when there are three nanorings, the connecting lines of the centers of the three nanorings form a right triangle, and the two right sides are along the horizontal and vertical directions respectively; when there are four nanorings, the outermost edges of the connecting lines of the centers of the four nanorings enclose an isosceles triangle, and the centers of three of the nanorings are on the same straight line, and this straight line is along the horizontal or vertical axis direction; when there are five nanorings, the outermost edges of the connecting lines of the centers of the five nanorings enclose a square, and the diagonals of the square are along the horizontal and vertical axis directions respectively, and the intersection point of the diagonals is the center of the central nanoring.

[0047] In some embodiments, the overlapping of the ring edges of multiple nanorings is as follows: the connections between the rings overlap with each other, the outer diameter of one ring is tangent to the inner diameter of another ring, and the distance between the centers of adjacent rings is the difference between the outer diameter of the nanoring and the ring width of the nanoring (d - w);

[0048] The contact connection of the ring edges of multiple nanorings is as follows: the distance between the centers of adjacent rings is l, and l ∈ (the difference between the outer diameter of the nanoring and the ring width of the nanoring (d - w), the outer diameter d of the nanoring).

[0049] This specification also discloses a preparation method for a magnetic nano multi-ring storage device, including:

[0050] Using one of deep ultraviolet lithography technology, extreme ultraviolet exposure technology, electron beam exposure technology, and nanoimprint technology to form a required template on a substrate material;

[0051] Using one of magnetron sputtering technology, electron beam evaporation technology, molecular beam epitaxy technology, and pulsed laser deposition technology to form a nanoring structure on the template to prepare the magnetic nano multi-ring storage device described in any one of the above.

[0052] In some embodiments, the substrate material is any one of a silicon wafer, a silicon oxide wafer, an ITO glass substrate, an FTO glass substrate, a K9 glass substrate, a quartz glass substrate, a sapphire single crystal wafer, and a gallium arsenide substrate.

[0053] In some embodiments, the material of the nanoring structure is a soft magnetic material (soft magnetic material thin film). Such as Ni 80 Fe 20 、CoFeB and Co2FeAl.

[0054] This specification also discloses an application of a magnetic nano multi-ring storage device, using the magnetic nano multi-ring storage device described in any one of the above to prepare a magnetic random access memory, a magnetic nano-switching device, a magnetic spin device, and a magnetic sensor.

[0055] In a specific embodiment, the preparation process of the magnetic nano multi-ring storage device is as follows:

[0056] Cut the silicon wafer into a size of 20×10 mm 2 (the main parameters of the silicon wafer: P-type, resistivity: <0.0015>, crystal orientation: <100>, thickness: 500 μm). After cleaning the silicon wafer, put it into an oven and bake it at 150 °C for 30 minutes. Then place it on a spin coater, suck an appropriate amount of deep ultraviolet photoresist with a pipette, and drop it all over the silicon wafer (PMMA positive photoresist of 950K, model AR-P679). Spin the photoresist at a speed of 5000 revolutions per minute for 60 seconds, take down the silicon wafer, put it into the oven, bake it at 100 °C for 45 seconds and then take it out. Put the spin-coated silicon wafer into a maskless far ultraviolet exposure machine with a wavelength of 248 nm, and the exposure dose is 25 mJ / cm 2 , and expose the designed magnetic nano multi-ring pattern on the silicon wafer using the positive photoresist process. After taking out the silicon wafer, put it into the developer and develop it for 50 seconds, then put it into the fixer for 50 seconds. After cleaning with deionized water, dry the surface of the silicon wafer with nitrogen, and use a microscope to adjust the magnification to 100 times to observe the nano-ring array pattern. Put the silicon wafer with a nano-ring array and a clear pattern into a magnetron sputtering instrument, set the Ar gas pressure to 5 mTorr, and the high vacuum to 5×10 -8 Torr, and sputter a Ni 80 Fe 20 (50) (nanometer) film on the silicon wafer, and then cover it with 5 nanometers of Au as a protective layer. Take out the silicon wafer from the magnetron sputtering instrument, soak it in the OK73 solution for 25 minutes, then put it in the ultrasonic for a few seconds and observe until the photoresist completely falls off, wash it with deionized water, and dry it with nitrogen to obtain the corresponding device. The preparation examples of the present invention prepare six forms of devices, including three types of devices with overlapping ring edges (see Appendix Figure 1a ) and three types of devices with contacting and connecting ring edges (see Appendix Figure 1b ). All device structures are composed of the same single nano-ring, and the size of a single nano-ring is: the outer diameter d is 1200 nm, the ring width w is 300 nm, and the thickness t is 50 nm. Devices with an overlapping ring edge combination between nano-rings are such as Figure 1aShown as follows: (i) A three-ring device with overlapping ring edges: The outer diameter of one ring contacts the inner diameter of the second ring, with a length of 2100 nm in the x direction, a width of 2100 nm in the y direction, and a thickness of 50 nm in the z direction; (ii) A four-ring device with overlapping ring edges: The combination mode between the contacting rings is similar to that of the overlapping three-ring device, with a length of 3000 nm in the x direction, a width of 2100 nm in the y direction, and a thickness of 50 nm in the z direction; (iii) A five-ring device with overlapping ring edges: The combination mode between the contacting rings is similar to that of the overlapping three-ring device, with a length of 3000 nm in the x direction, a width of 3000 nm in the y direction, and a thickness of 50 nm in the z direction. Figure 1b The combination mode between the nano-rings is a device with ring-edge contact connection. The distance l between the centers of two adjacent rings in the ring-edge contact connection is 1100 nm. (iv) A three-ring device with ring-edge contact connection: 2300 nm in length in the x direction, 2300 nm in width in the y direction, and 50 nm in thickness in the z direction; (v) A four-ring device with ring-edge contact connection: 3400 nm in length in the x direction, 2300 nm in width in the y direction, and 50 nm in thickness in the z direction; (vi) A five-ring device with ring-edge contact connection: 3400 nm in length in the x direction, 3400 nm in width in the y direction, and 50 nm in thickness in the z direction.

[0057] Six typical magnetic nano-ring memory devices of the present invention were detected using a microfocus magneto-optical Kerr effect instrument to obtain the corresponding hysteresis loops of each device, and the magnetic domains at the turning points of the hysteresis loops were observed through a magnetic force microscope. At the same time, micromagnetic simulations were also carried out on the devices. The results are shown in Figures 2a to 2c and Figures 3a to 3c .

[0058] In the multi-ring device with overlapping ring edges, due to the strong exchange coupling effect dominating the magnetization reversal process, the hysteresis loop shows a three-step reversal, that is, there are two stable intermediate states. This is inconsistent with the two transitions of the positive onion state - vortex state - anti-onion state magnetic domains in a single nano-ring device, indicating that new magnetic states may appear during the reversal process, which is very important for applications such as magnetic random access memories, magnetic nano-switching devices, magnetic spin devices, and magnetic sensors. As shown in Figure 2a , when the external magnetic field of the three-ring device with overlapping ring edges is 0 Oe, the top nano-ring forms a 360° vortex state that rotates clockwise along the external field direction, and the bottom two rings show vortex states with opposite chirality and there are domain walls in the overlapping region; when the external magnetic field increases to -150 Oe (the first intermediate state in the hysteresis loop), the upper and lower rings on the same side show opposite chirality and there are domain walls in the overlapping region, and the right lower ring transforms into an onion state; when the external magnetic field further increases to -450 Oe (the second intermediate state in the hysteresis loop), all three rings show a distorted onion state. According to Figure 2bAs shown in the figure, as the external magnetic field increases, the top ring of the device with four overlapping rings maintains a 360° clockwise vortex state, the two rings on the bottom sides show vortex states of opposite chirality (0Oe), and the middle ring is always in a twisted state; the left ring below shows the transition from the onion state (the first intermediate state) to the counterclockwise vortex state (the second intermediate state). Figure 2c As shown, the ring edge overlapping five-ring device increases with the external magnetic field, and the upper and lower two rings keep the vortex state of opposite chirality, the ring on the left is onion state, the right ring shows the transition of vortex state (0Oe)-onion state (first intermediate state)-onion state (second intermediate state), and the middle ring shows the transition of twisted state (0Oe)-onion state (first intermediate state)-twisted state (second intermediate state). The above experimental detection and theoretical simulation results prove that the ring edge overlapping type magnetic nano multi-ring device of the present invention has a novel magnetic domain structure. As a comparison, in the ring edge overlapping double ring device under the same conditions as the present embodiment (single nano ring has the same ring thickness and ring width), its second intermediate state is unstable, this is because the difference of the two intermediate magnetic domain states in the double ring device is not big, just the domain wall has a small movement in the overlapping area, and the two intermediate states of the ring edge overlapping multi-ring device of the present invention have shown different novel magnetic domain states, so it is more stable. In the read and write process of magnetic random access memory device, the unit of storage can be defined as "0" and "1" respectively by the difference of vortex state chirality. For the device of the present invention, the new stable magnetic state at the step of the hysteresis loop can provide more flexible and rich switching information or read-write information compilation for the further application of the magnetic nanodevice.

[0059] The interaction of the ring-edge contact-connected multi-ring device is weaker than that of the ring-edge overlapped multi-ring device, so the hysteresis loop shows a two-step flip, that is, there is only one stable intermediate state, which is similar to the two transitions of the positive onion state-vortex state-anti-onion state magnetic domains of a single nanoring device. Figure 3a As shown, the stable intermediate state of the three-ring device connected by ring-edge contact is three vortex states, in which the chirality of the upper and lower rings on the same side is opposite, and the chirality of the lower two rings is the same; Figure 3b The stable intermediate state of the four-ring device connected by the ring edge contact is that the three outermost rings are all in the counterclockwise vortex state with the same chirality, and the middle ring is in the onion state. Figure 3c In the ring-edge contact-connected five-ring device, the four outermost rings are all in vortex state, the three upper rings are of the same counterclockwise chirality, the lowermost ring is clockwise chirality, and the middle ring is in onion state. The above experimental detection and theoretical simulation results prove that the ring-edge contact-connected magnetic nano multi-ring devices of the present invention also have a new magnetic domain structure.

[0060] In addition, the chirality of the vortex state of the device of the present invention is controllable. Among all the ring-edge overlapping multi-ring devices in this embodiment, the topmost (perpendicular to the direction of the external field application) nano-ring always maintains a 360° vortex state with clockwise rotation, which further illustrates that the chirality of the multi-ring is determined by its configuration. In the ring-edge overlapping four-ring device, the rightmost nano-ring along the direction of the external field application always maintains a counterclockwise vortex state; in the ring-edge overlapping five-ring device, the two nano-rings at the topmost (clockwise rotation) and the bottommost (counterclockwise rotation) (perpendicular to the direction of the external field application) exhibit vortex states with opposite chirality. Among all the ring-edge contact-connected multi-ring devices in this embodiment, the control of the intermediate state vortex chirality is more obvious: all the topmost rings in the three devices exhibit a vortex state with counterclockwise rotation along the direction of the applied external field, and the nano-rings arranged vertically and exhibiting a vortex state have opposite vortex chirality; the nano-rings arranged horizontally and in a vortex state have the same vortex chirality. This is because the magnetic field is applied along the x direction, and the exchange coupling in the horizontal direction is stronger than that in the vertical direction. Compared with the prior art, in a single-ring device with the same ring thickness and ring width as the single nano-ring in the device of this embodiment, the chirality of the vortex state is unpredictable. The two different configurations of magnetic nano multi-ring devices of the present invention can significantly control and adjust the chirality characteristics of the vortex state, which not only improves the flexibility and efficiency of magnetic nano devices in information storage and data processing, but also directly affects the improvement of storage density and the reduction of energy consumption, playing a promoting role in the development of magnetic storage technology.

[0061] In a specific embodiment, the application process of the magnetic nano multi-ring storage device is as follows:

[0062] Figure 4 and Figure 5 are respectively the schematic structural diagrams of the circuit of the ring-edge overlapping three-ring device used in the read-write device embodiment. In this embodiment, it is necessary to cover a 2-nm MgO on the single-layer Ni 80 Fe 20 device, evaporate 3 nm of CoFeB on the MgO, and finally cover 3 nm of Ta as a protective layer to make the ring-edge overlapping three-ring device a magnetic storage unit. Figure 4 is the signal writing circuit. After passing a current (Iwrite in Figure 4 ), the current passes through the ring-edge overlapping three-ring storage device, and the signal is written. It is required that the input current does not break the magnetization state of the CoFeB layer. After the current passes through the bit line and the word line, the bias signal in the readout line is 0, and the access transistor channel is closed. Therefore, the rotation direction of the vortex state of the Ni 80 Fe 20 layer can be determined by changing the magnitude of the synchronous magnetic field, thereby defining the write signals "0" and "1". If Ni 80 Fe 20The rotation directions of the vortex states of the NiFe layer and the CoFeB layer are the same, and the signal is "1"; otherwise, the signal is "0". Figure 5 An embodiment of Figure 5 is a signal readout circuit. After the signal is written into the three-ring memory device with overlapping ring edges, a read voltage ( Figure 5 Vread in Figure 5 ) is applied to the bit line to read the signal. At the same time, a selection voltage ( Figure 5 Vselect in Figure 5 ) is applied to the word line. At this time, the access transistor channel is opened, so the current flowing through the bit line can be detected by the sense amplifier. In this case, when the rotation directions of the vortex states of the Ni 80 Fe 20 layer and the CoFeB layer are opposite, it is in a high-resistance state; otherwise, when the rotation directions of the vortex states of the Ni 80 Fe 20 layer and the CoFeB layer are the same, it is in a low-resistance state. The recording of one byte is determined by the detected current value. Compared with the prior art, when using the device of the present invention as a magnetic random access memory, its coding code has more compilable options. In addition, the magnetic nano multi-ring device of the present invention can control and adjust the chiral characteristics of the vortex state, further improving the flexibility and efficiency of information storage and data processing of magnetic nano-devices.

[0063] The above-described embodiments are used to illustrate the present invention, not to limit the present invention. Therefore, changes in the example values or replacement of equivalent elements still belong to the scope of the present invention.

[0064] From the above detailed description, those of ordinary skill in the art can clearly understand that the present invention can indeed achieve the aforementioned objectives, and it actually meets the requirements of the Patent Law.

[0065] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention. The above description is only for the preferred embodiments of the present invention and is not intended to limit the present invention. It should be noted that any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0066] It should be noted that the above description of the process is only for illustration and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the process under the guidance of this specification. However, these modifications and changes are still within the scope of this specification.

[0067] The basic concepts have been described above. Obviously, for those of ordinary skill in the art after reading this application, the above invention disclosure is only for illustration and does not constitute a limitation to this application. Although not explicitly stated here, those of ordinary skill in the art may make various modifications, improvements and corrections to this application. Such modifications, improvements and corrections are proposed in this application, so such modifications, improvements and corrections still fall within the spirit and scope of the exemplary embodiments of this application.

[0068] Meanwhile, this application uses specific terms to describe the embodiments of this application. For example, "one embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned two or more times at different positions in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of this application can be appropriately combined.

[0069] In addition, those of ordinary skill in the art can understand that various aspects of this application can be illustrated and described by several patentable types or situations, including any new and useful process, machine, product or combination of substances, or any new and useful improvement thereof. Therefore, various aspects of this application can be implemented entirely by hardware, can be implemented entirely by software (including firmware, resident software, microcode, etc.), or can be implemented by a combination of hardware and software. The above hardware or software can all be referred to as "units", "modules" or "systems".

[0070] In addition, unless explicitly stated in the claims, the order of the processing elements and sequences, the use of numerical letters, or the use of other names in this application are not used to limit the order of the processes and methods of this application. Although some currently considered useful invention embodiments are discussed through various examples in the above disclosure, it should be understood that such details only serve the purpose of illustration. The appended claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that conform to the essence and scope of the embodiments of this application.

[0071] Similarly, it should be noted that, in order to simplify the expression of the disclosure of this application and thus help the understanding of one or more invention embodiments, in the previous description of the embodiments of this application, sometimes multiple features are grouped into one embodiment, drawing or description thereof. However, this method of this application should not be construed as reflecting the intention that the claimed subject matter requires more features than those explicitly recited in each claim. On the contrary, the subject matter of the invention should have fewer features than the above single embodiment.

Claims

1. A magnetic nano-multi-ring storage device, characterized in that, Comprising: A substrate; Units attached to the substrate; Wherein, the units are composed of a plurality of nanorings with overlapping or contacting ring edges; The arrangement of the plurality of nanorings is as follows: taking one nanoring as the center, the number of nanorings increases outward along the horizontal and vertical axes of the ring plane; when there are three nanorings, the connection lines of the centers of the three nanorings form a right triangle, and the two right sides are along the horizontal and vertical directions respectively; when there are four nanorings, the outermost edges of the connection lines of the centers of the four nanorings enclose an isosceles triangle, and the centers of three of the nanorings are on the same straight line, and this straight line is along the horizontal or vertical axis direction; when there are five nanorings, the outermost edges of the connection lines of the centers of the five nanorings enclose a square, and the diagonals of the square are along the horizontal and vertical axis directions respectively, and the intersection point of the diagonals is the center of the central nanoring.

2. The magnetic nano-multiring storage device according to claim 1, characterized in that, The material of the substrate is an insulating material.

3. The magnetic nano-multiring storage device according to claim 1, wherein The nanoring is composed of a soft magnetic material thin film.

4. The magnetic nano-multi-ring memory device according to claim 1, wherein The outer diameter of the nanoring is d, the ring width is w, and the thickness is t, where w = d / 4, d ∈ (100 nm, 1.5 μm), and t ∈ (20 nm, 80 nm).

5. The magnetic nano polycyclic memory device according to claim 1, wherein The overlapping of the ring edges of the plurality of nanorings is: the connections between the rings overlap with each other, the outer diameter of one ring is tangent to the inner diameter of another ring, and the distance between the centers of two adjacent rings is the difference between the outer diameter of the nanoring and the ring width of the nanoring.

6. The magnetic nano-multiring storage device according to claim 1, wherein The contacting connection of the ring edges of the plurality of nanorings is: the distance between the centers of two adjacent rings is l, l ∈ (the difference between the outer diameter of the nanoring and the ring width of the nanoring, the outer diameter of the nanoring).

7. A preparation method of a magnetic nano multi-ring storage device, characterized in that, Comprising: Using one of deep ultraviolet lithography technology, extreme ultraviolet exposure technology, electron beam exposure technology, and nanoimprint technology to form a required template on the substrate material; Using one of magnetron sputtering technology, electron beam evaporation technology, molecular beam epitaxy technology, and pulsed laser deposition technology to form a nanoring structure on the template to prepare the magnetic nano multi-ring storage device according to any one of claims 1 to 6.

8. The preparation method of the magnetic nano polycyclic storage device according to claim 7, characterized in that, The substrate material is any one of a silicon wafer, a silicon oxide wafer, an ITO glass substrate, an FTO glass substrate, a K9 glass substrate, a quartz glass substrate, a sapphire single crystal wafer, and a gallium arsenide substrate.

9. Application of a magnetic nano multi-ring storage device, characterized in that, Using the magnetic nano multi-ring storage device according to any one of claims 1 to 6 to prepare a magnetic random access memory, a magnetic nano switch device, a magnetic spin device, and a magnetic sensor.

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