Magnetic recording apparatus and magnetic memory

Abstract

The invention relates to the technical field of magnetic storage, and discloses magnetic recording equipment which comprises a substrate and a strip-shaped information storage layer. The substrate comprises a base made of a flexible material, the strip-shaped information storage layer comprises a plurality of ferromagnetic layers made of ferromagnetic materials and a plurality of spacing layers made of non-magnetic materials, the spacing layers are located between the ferromagnetic layers, and the ferromagnetic layers and the spacing layers are alternately stacked on the substrate. As the magnetization direction of each ferromagnetic layer can be changed by writing, the proportion of different magnetization directions of the ferromagnetic layers in the strip-shaped information storage layer can be changed by adjusting the energy level of the energy auxiliary device of the magnetic field writing head and turning over the magnetization directions of the ferromagnetic layers of the corresponding number of layers, so that different data storage states can be represented; therefore, polymorphic storage is realized, the storage density is improved, and the upper limit of the data storage capacity is improved. The invention also discloses a magnetic memory.

Description

Technical Field

[0001] The present application relates to the field of magnetic storage technology, for example, to a magnetic recording device and a magnetic storage device. Background Art

[0002] At present, magnetic storage devices represented by hard disk drives are important tools for expanding computer data storage capabilities. Existing disk storage devices mostly use single-layer magnetic recording media with vertical (or in-plane) magnetic anisotropy because the spatial resolution of the read head is insufficient and can only be used to detect magnetic fields in a single direction. This magnetic recording medium has only two stable states: the magnetization direction is vertically upward (horizontally to the left) or vertically downward (horizontally to the right), so a single storage unit of the disk storage device can only store one binary information, and the storage density is low, which cannot well meet the growing data storage needs.

[0003] The related technology discloses a magnetic recording device, including: a substrate, and a magnetic recording film on the substrate, the magnetic recording film is circular, and includes three ferromagnetic layers separated by two non-magnetic intermediate layers, the easy magnetization directions of the three ferromagnetic layers are respectively along the x, y, and z directions, the z direction is the vertical direction, the x and y directions are in-plane directions and are respectively along the radial and tangential directions.

[0004] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:

[0005] By adopting relevant technologies, different binary information can be stored by setting up multiple ferromagnetic layers with different easy magnetization directions, which improves the storage density of the disk to a certain extent. On this basis, the method of stacking multiple disks can further increase the data storage capacity. However, in actual application, due to the limitation of the overall chassis volume, the number of disks that can be stacked is small, resulting in the storage capacity easily reaching the upper limit.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0007] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0008] The embodiments of the present disclosure provide a magnetic recording device and a magnetic memory to increase the upper limit of data storage capacity.

[0009] In some embodiments, a magnetic recording device includes: a substrate, including a base made of a flexible material; a strip-shaped information storage layer, including at least two ferromagnetic layers made of ferromagnetic material and at least one spacer layer made of non-magnetic material; wherein the spacer layer is located between the ferromagnetic layers, and the ferromagnetic layers and the spacer layers are alternately stacked on the substrate.

[0010] Optionally, the substrate further includes: at least one coating layer disposed on the lower surface of the base.

[0011] Optionally, the magnetization direction of the ferromagnetic layer includes a perpendicular direction and / or an in-plane direction.

[0012] Optionally, the strip-shaped information storage layer comprises: a plurality of storage units, each storage unit being a strip-shaped information storage layer of a set length; wherein each storage unit represents a corresponding data storage state through a distribution ratio of a magnetization direction of a corresponding ferromagnetic layer.

[0013] Optionally, the easy magnetization directions of the ferromagnetic layers of a single memory cell are the same.

[0014] Optionally, the strip-shaped information storage layer further includes: at least one isolation layer, which is arranged between the substrate and the strip-shaped information storage layer and is used to reduce the energy transferred to the substrate during the writing process.

[0015] Optionally, the strip-shaped information storage layer further includes: at least one seed layer, disposed between the substrate and the strip-shaped information storage layer.

[0016] Optionally, the magnetic recording device also includes: a magnetic field write head, including a magnetic field generating device and an energy assisting device, the magnetic field generating device is used to generate a vertical or in-plane magnetic field in a first region of the strip-shaped information storage layer, and the energy assisting device is used to reduce the magnetic field intensity of the coercive field of the magnetic moment in a second region of the strip-shaped information storage layer; wherein the first region includes the second region.

[0017] Optionally, the magnetic recording device also includes: a controller configured to adjust the energy level of the energy assist device to flip the magnetization direction of the ferromagnetic layer of the target number of layers according to the data to be written when performing polymorphic writing to the strip information storage layer through the magnetic field write head.

[0018] In some embodiments, a magnetic memory includes: the magnetic recording device described above.

[0019] The magnetic recording device and magnetic storage provided by the embodiments of the present disclosure can achieve the following technical effects:

[0020] The magnetic recording device includes a substrate and a strip-shaped information storage layer. The substrate includes a base made of a flexible material, and the strip-shaped information storage layer includes at least two ferromagnetic layers made of ferromagnetic materials and at least one spacer layer made of non-magnetic materials, wherein the spacer layer is located between the ferromagnetic layers, and the ferromagnetic layers and the spacer layers are alternately stacked on the substrate. Since the magnetization direction of each ferromagnetic layer can be changed by writing, the magnetization direction of the ferromagnetic layer of the corresponding number of layers can be flipped by adjusting the energy level of the energy auxiliary device of the magnetic field write head, so that the proportion of different magnetization directions of the ferromagnetic layers in the strip-shaped information storage layer can be changed to represent different data storage states, thereby realizing polymorphic storage, improving storage density, and increasing the upper limit of data storage capacity. In addition, the strip-shaped information storage layer is arranged on a flexible substrate, and the storage tape surface can be rolled up by using the flexible substrate, so that the longitudinal tape surface width dimension is used in information storage by taking advantage of the rollability of the flexible substrate, thereby increasing the upper limit of data storage capacity.

[0021] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0023] Figure 1 is a structural schematic diagram of a magnetic recording device provided by an embodiment of the present disclosure;

[0024] Figure 2 is a structural schematic diagram of another magnetic recording device provided by an embodiment of the present disclosure;

[0025] Figure 3 is a schematic diagram of a magnetic recording device in use provided by an embodiment of the present disclosure;

[0026] Figure 4 It is a schematic diagram of another magnetic recording device in use provided by an embodiment of the present disclosure.

[0027] Reference numerals:

[0028] 10: substrate; 11: base; 12: coating;

[0029] 20: strip information storage layer; 21: ferromagnetic layer; 22: spacer layer; 23: isolation layer; 24: seed layer; 25: first ferromagnetic layer; 26: second ferromagnetic layer; 27: third ferromagnetic layer; 28: fourth ferromagnetic layer; 29: first spacer layer; 30: second spacer layer; 31: third spacer layer; 32: fifth ferromagnetic layer; 33: fourth spacer layer;

[0030] 40: magnetic field writing head; 41: energy assist device. DETAILED DESCRIPTION

[0031] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0032] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

[0033] Combination Figures 1 to 4 As shown, the embodiment of the present disclosure discloses a magnetic recording device, including a substrate 10 and a strip-shaped information storage layer 20. The substrate 10 includes a base 11 made of a flexible material; the strip-shaped information storage layer 20 includes at least two ferromagnetic layers 21 made of ferromagnetic materials and at least one spacer layer 22 made of a non-magnetic material; wherein the spacer layer 22 is located between the ferromagnetic layers 21, and the ferromagnetic layers 21 and the spacer layers 22 are alternately stacked on the substrate 10.

[0034] In the embodiment of the present disclosure, the strip-shaped information storage layer 20 may include a plurality of alternately stacked ferromagnetic layers 21 made of ferromagnetic materials and spacer layers 22 made of non-magnetic materials.

[0035] In the disclosed embodiment, the material constituting the substrate 11 includes flexible materials such as polyethylene terephthalate, polyimide, polyvinyl chloride and / or polypropylene, and the thickness of the substrate 11 ranges from 0.5 to 50 μm. The substrate 11 composed of the above materials can provide mechanical support for the ferromagnetic layer 21, can keep the properties of the ferromagnetic layer 21 unchanged during deformation and bending, and maintain good recovery ability after multiple bending deformations.

[0036] In the embodiment of the present disclosure, the strip-shaped information storage layer 20 includes a ferromagnetic layer 21 and a spacer layer 22. The ferromagnetic layer 21 and the spacer layer 22 are alternately stacked on the substrate 10. Figure 1As shown, the ferromagnetic layer 21 includes a first ferromagnetic layer 25 stacked alternately on the substrate 10, a first spacer layer 29 stacked on the first ferromagnetic layer 25, a second ferromagnetic layer 26 stacked on the first spacer layer 29, a second spacer layer 30 stacked on the second ferromagnetic layer 26, a third ferromagnetic layer 27 stacked on the second spacer layer 30, a third spacer layer 31 stacked on the third ferromagnetic layer 27, a fourth ferromagnetic layer 28 stacked on the third spacer layer 31, and at least one subsequent ferromagnetic layer 21 and a subsequent spacer layer 22, wherein each subsequent ferromagnetic layer 21 is stacked on the previous spacer layer 22, and each subsequent spacer layer 22 is stacked on the previous subsequent ferromagnetic layer 21, until the fourth spacer layer 33 stacked on the previous ferromagnetic layer 21 and the fifth ferromagnetic layer 32 stacked on the fourth spacer layer 33, thereby completing the alternating stacking of all ferromagnetic layers 21 and spacer layers 22 on the substrate 10.

[0037] The magnetic recording device provided by the embodiment of the present disclosure is provided with a structure of a multi-layer ferromagnetic layer 21, and it is used as a storage medium. Since the multi-layer film can enhance the storage stability through interlayer coupling, and the perpendicular magnetic anisotropy of the multi-layer ferromagnetic layer 21 can be superimposed, the magnetic recording device of the embodiment of the present disclosure has high storage stability. In addition, the structure of the multi-layer ferromagnetic layer 21 can present a continuously adjustable multi-domain state in a storage unit of the same size. Therefore, by changing the ratio of different magnetization directions of the multi-layer ferromagnetic layer, different data storage states can be represented, thereby realizing multi-bit storage, further improving the storage capacity, and increasing the storage density. On this basis, the strip-shaped information storage layer 20 is provided on the flexible substrate 11, and the storage tape surface can be rolled up by using the flexible substrate 11, so that the longitudinal tape surface width dimension is used for information storage by taking advantage of the rollability of the flexible substrate 11, thereby increasing the upper limit of the data storage capacity.

[0038] Optionally, combined Figure 1 As shown, the substrate 10 further includes at least one coating layer 12. The coating layer 12 is disposed on the lower surface of the base 11.

[0039] In the disclosed embodiment, the coating 12 may be a single layer or multiple layers. The coating 12 may be made of materials such as carbon black, ceramic particles and / or resin. By forming the coating 12 with materials such as carbon black, static electricity accumulation can be dispersed and reduced, and potential damage to the ferromagnetic layer 21 caused by static electricity can be reduced. Forming the coating 12 with chemically inert materials such as ceramic particles can protect the substrate 11 from corrosion by chemical substances and improve the chemical stability of the storage medium.

[0040] Thus, by providing the coating layer 12 on the lower surface of the substrate 11 , it is possible to prevent static electricity accumulation, enhance mechanical durability, and improve the winding characteristics of the substrate 11 .

[0041] Optionally, the magnetization direction of the ferromagnetic layer 21 includes a perpendicular direction and / or an in-plane direction.

[0042] In the embodiment of the present disclosure, Figure 3 and Figure 4 As shown, the magnetization direction of the multi-layer ferromagnetic layer 21 can be a vertical direction, that is, perpendicular to the surface of the substrate 11 (vertical magnetization), or an in-plane direction, within the surface of the substrate 11 (in-plane magnetization), or a vertical direction and an in-plane direction. The combination of vertical and in-plane magnetization directions can provide additional magnetization states, which helps to improve the thermal stability and anti-interference ability of the stored data. In addition, since different magnetization directions can represent different data states, polymorphic storage can be achieved, thereby storing more data in the same physical space.

[0043] In this way, the magnetization direction of the multilayer ferromagnetic layer 21 includes a vertical direction and / or an in-plane direction, so that the magnetization direction of the multilayer ferromagnetic layer 21 can be flipped by the vertical direction or in-plane direction magnetic field generated by the magnetic field write head 40 to achieve multi-bit storage.

[0044] Optionally, the strip-shaped information storage layer 20 includes: a plurality of storage units. Each storage unit is a strip-shaped information storage layer 20 of a set length; wherein each storage unit represents a corresponding data storage state through a distribution ratio of the magnetization direction of the corresponding ferromagnetic layer 21 .

[0045] In the embodiment of the present disclosure, a plurality of storage units are evenly distributed along the length direction of the strip-shaped information storage layer 20. Each storage unit includes a continuous multi-layer film structure in which a ferromagnetic layer 21 and a spacer layer 22 are alternately stacked in the vertical direction of the substrate 10, and non-magnetic materials can be filled between each storage unit. Figure 3 and Figure 4 As shown, each column of a continuous multilayer film structure in which ferromagnetic layers 21 and spacer layers 22 are alternately stacked is a storage unit, and multiple storage units are evenly distributed along the length direction of the strip-shaped information storage layer 20. The gap between two storage units can be filled with non-magnetic materials to separate the stored units.

[0046] In the embodiment of the present disclosure, each storage unit represents the corresponding data storage state through the distribution ratio of the magnetization direction of the corresponding ferromagnetic layer 21. Figure 3As shown, the easy magnetization direction of the ferromagnetic layer 21 corresponding to each storage unit is vertically downward. After the magnetic field write head 40 flips the magnetization direction of the ferromagnetic layer 21, the first storage unit on the left includes at least two ferromagnetic layers 21 with magnetization directions vertically upward and three ferromagnetic layers 21 with magnetization directions vertically downward from top to bottom, and the second storage unit on the left includes ferromagnetic layers 21 with magnetization directions vertically upward from top to bottom. Since the proportions of different magnetization directions of the ferromagnetic layers corresponding to the first storage unit on the left and the second storage unit on the left are different, the data storage states represented by the first storage unit on the left and the second storage unit on the left are different. Figure 4 As shown, the easy magnetization direction of the ferromagnetic layer 21 corresponding to each storage unit is horizontal to the left. After the magnetic field write head 40 flips the magnetization direction of the ferromagnetic layer 21, the first storage unit on the left includes at least two ferromagnetic layers 21 with magnetization directions horizontal to the right and three ferromagnetic layers 21 with magnetization directions horizontal to the left from top to bottom, and the second storage unit on the left has ferromagnetic layers 21 with magnetization directions horizontal to the right from top to bottom. Since the proportions of different magnetization directions of the ferromagnetic layers corresponding to the first storage unit on the left and the second storage unit on the left are different, the data storage states represented by the first storage unit on the left and the second storage unit on the left are different.

[0047] In this way, by changing the magnetization direction of the ferromagnetic layer 21 in the storage unit, the ratio of different magnetization directions of the ferromagnetic layer 21 in the storage unit can be changed, so that each storage unit can represent a different data storage form, realizing more complex information storage than binary information. In addition, multiple storage units are evenly distributed along the length direction of the strip-shaped information storage layer 20, and the strip-shaped information storage layer 20 can be curled, further improving the data storage density.

[0048] Optionally, the easy magnetization directions of the ferromagnetic layers 21 of a single memory cell are the same.

[0049] In the disclosed embodiment, the easy magnetization direction of each ferromagnetic layer 21 may be in an in-plane direction or a vertical direction.

[0050] In this way, since the easy magnetization directions of the ferromagnetic layers 21 of each storage unit are the same, the magnetic field write head 40 only needs to generate a magnetic field in a single direction to change the magnetization directions of the ferromagnetic layers 21 in the active area, thereby changing the ratio of the overall magnetization directions of all ferromagnetic layers 21 in the vertical direction of the substrate 10, and realizing that multiple ferromagnetic layers 21 represent different data storage forms. Optionally, the ferromagnetic material includes a single metal or alloy that exhibits ferromagnetism.

[0051] In the embodiments of the present disclosure, the single metal exhibiting ferromagnetism includes Cr (chromium), Mn (manganese), Co (cobalt), Fe (iron), Ni (nickel) or other metals exhibiting ferromagnetism. The alloy exhibiting ferromagnetism includes an alloy composed of multiple metals among Cr, Mn, Co, Fe, Ni and other metals exhibiting ferromagnetism and exhibiting ferromagnetism. The alloy exhibiting ferromagnetism also includes an alloy of the above-mentioned single metal or alloy with at least one of B (boron), C (carbon) and N (nitrogen), such as Co-Fe, Co-Fe-B, Ni-Fe, CoNi, CoPt, BaFe, or SrFe.

[0052] Thus, the ferromagnetic material includes a single metal or alloy exhibiting ferromagnetism, and the alloy exhibiting ferromagnetism generally has a higher saturation magnetization and a lower coercive force than a single metal. Therefore, the magnetic properties of the ferromagnetic layer 21 can be optimized by controlling the alloy composition constituting the ferromagnetic layer 21, so as to meet specific storage requirements.

[0053] Optionally, the spacer layer 22 is made of a metal material and / or a metal oxide material.

[0054] In the disclosed embodiment, the metal material constituting the spacer layer 22 includes an alloy material composed of one or more metals such as Nb (niobium), Ta (tantalum), Cr (chromium), Mo (molybdenum), W (tungsten), Re (rhenium), Ru (ruthenium), Os (osmium), Rh (rhodium), Ir (iridium), Pt (platinum), Cu (copper), Ag (silver), Au (gold), Mo (molybdenum), Pd (palladium), Bi (bismuth), Ti (titanium), etc. The metal oxide material constituting the spacer layer 22 includes metal oxide materials such as MgO (magnesium oxide) and AlO (aluminum oxide).

[0055] Thus, by providing the spacer layer 22 made of non-magnetic material between the ferromagnetic layers 21, the ferromagnetic layer 21 can be provided with DMI (Dzyaloshinskii-Moriya interaction), interlayer coupling and / or perpendicular magnetic anisotropy required for forming stable magnetic storage.

[0056] Optionally, the magnetic recording device further includes at least one isolation layer 23. The isolation layer 23 is disposed between the substrate 10 and the strip-shaped information storage layer 20, and is used to reduce the energy transferred to the base 11 during the writing process.

[0057] In the embodiment of the present disclosure, Figure 1As shown, the isolation layer 23 is arranged between the substrate 10 and the ferromagnetic layer 21 at the bottom of the strip-shaped information storage layer 20. One or more isolation layers 23 can be arranged between the substrate 10 and the ferromagnetic layer 21 according to the heat insulation requirements. The material constituting the isolation layer 23 can be a material with thermal stability and chemical stability, such as a nano-ceramic film (such as titanium oxide, indium tin oxide, etc.), a polyimide film, a polytetrafluoroethylene film, etc. It can also be a common magnetic shielding material such as iron-nickel alloy, iron-silicon alloy, iron-aluminum alloy, ferrite, nickel-copper alloy, etc., to effectively block or absorb the magnetic field and reduce interference with other storage units. The thickness of the isolation layer 23 ranges from 0.1 to 5 μm.

[0058] In this way, by setting an isolation layer 23 between the substrate 10 and the strip information storage layer 20 (ferromagnetic layer 21), the energy transmitted by the energy assist device 41 of the magnetic field write head 40 can be blocked during the writing process, thereby preventing the substrate 11 from failing due to overheating and preventing other storage units from reducing storage stability due to the auxiliary energy, thereby ensuring the stability and reliability of the magnetic recording device when writing data.

[0059] Optionally, the magnetic recording device further includes at least one seed layer 24. The seed layer 24 is disposed between the substrate 10 and the strip-shaped information storage layer 20.

[0060] In the embodiment of the present disclosure, the seed layer 24 is disposed between the substrate 10 and the bottom ferromagnetic layer 21 of the strip-shaped information storage layer 20. Figure 1 As shown, one or more seed layers 24 may be disposed between the isolation layer 23 and the bottom ferromagnetic layer 21 of the strip-shaped information storage layer 20. The material constituting the seed layer 24 includes one or more of Nb (niobium), Ta (tantalum), Cr (chromium), Mo (molybdenum), W (tungsten), Re (rhenium), Ru (ruthenium), Os (osmium), Rh (rhodium), Ir (iridium), Pt (platinum), Cu (copper), Ag (silver), Au (gold), NiFe (nickel iron), TaB (tantalum boron), and TaN (tantalum nitride). The thickness of the seed layer 24 ranges from 1 to 500 nm.

[0061] Thus, by arranging one or more seed layers 24 between the isolation layer 23 and the ferromagnetic layer 21 at the bottom of the strip-shaped information storage layer 20, the material of the ferromagnetic layer 21 can be grown more orderly and flat, thereby forming a sufficiently large storage stability.

[0062] Optionally, a plurality of strip-shaped information storage layers 20 are arranged on the substrate 10 .

[0063] In the embodiment of the present disclosure, Figure 2As shown, the arrangement of multiple strip-shaped information storage layers 20 on the substrate 10 can be uniformly arranged in the axial direction of the base 11. By uniformly arranging multiple strip-shaped information storage layers 20 in the axial direction of the substrate 10, more storage units can be accommodated in a limited space, thereby improving the storage density of the storage medium. In addition, the uniformly arranged strip-shaped information storage layers 20 can make the writing and reading processes more uniform and consistent, which helps to improve the accuracy of data writing and the reliability of reading.

[0064] In this way, on each strip-shaped information storage layer 20, a strip-shaped information storage layer 20 of a set length can be used as a storage unit. Since the magnetic domain area of ​​different magnetic moment directions can be changed by writing, each storage unit can represent different data storage states by the magnetization direction distribution ratio of the multi-layer continuous film structure of the alternately stacked ferromagnetic layer 21 and the spacer layer 22, thereby realizing polymorphic storage in a single storage unit. By arranging multiple strip-shaped information storage layers 20 on the substrate 11 and using the magnetization direction distribution ratio of the multi-layer continuous film structure of the alternately stacked ferromagnetic layer 21 and the spacer layer 22 to realize polymorphic storage, the storage density and capacity are improved.

[0065] Optionally, the magnetic recording device further includes a magnetic field write head 40. The magnetic field write head 40 includes a magnetic field generating device and an energy assisting device 41, wherein the magnetic field generating device is used to generate a vertical or in-plane magnetic field in a first region of the strip-shaped information storage layer 20, and the energy assisting device 41 is used to reduce the magnetic field intensity of the coercive field of the magnetic moment in a second region of the strip-shaped information storage layer 20; wherein the first region includes the second region.

[0066] In the disclosed embodiment, the magnetic field write head 40 can be positioned above the strip-shaped information storage layer 20 of the magnetic storage device, and a magnetic field can be generated by a magnetic field generating device, and auxiliary energy can be generated by an energy assist device 41, wherein the auxiliary energy includes thermal assistance or microwave assistance, such as a laser-heated thermal head, or an oscillator that generates microwaves of a set frequency. According to the data to be written, the direction and intensity of the magnetic field are controlled, and the magnetic field and the auxiliary energy are jointly applied to the strip-shaped information storage layer 20 to change the magnetization direction of one or more ferromagnetic layers 21 in the strip-shaped information storage layer 20. Move the magnetic tape so that the strip-shaped information storage layer 20 passes through the magnetic field write head 40, thereby writing the data to be written in the ferromagnetic layer 21. In addition, by miniaturizing the active area of ​​the laser-heated thermal head or oscillator, it is possible to selectively change the state of part of the magnetic moment in the storage unit to achieve multi-bit storage in a single storage unit. Combined with Figure 3As shown, the magnetic field generating device generates a vertical magnetic field, and generates a smaller energy through the energy assisting device 41, thereby reducing the magnetic field strength of the coercive field of the magnetic moment in the second region, so that the vertical magnetization direction of the multilayer ferromagnetic layer 21 in the first region changes from vertically downward to vertically upward. Therefore, the first storage unit on the left includes at least two ferromagnetic layers 21 with a magnetization direction of vertically upward and three ferromagnetic layers 21 with a magnetization direction of vertically downward from top to bottom. Then, the second storage units on the left are written by the magnetic field writing head 40 to enhance the energy generated by the energy assisting device 41 to increase the size of the second region, thereby reducing the magnetic field strength of the coercive field of the magnetic moment in a larger region in the first region, so that the magnetization direction of more ferromagnetic layers 21 is reversed, and the magnetization direction of the ferromagnetic layer 21 of the second storage unit on the left from top to bottom is changed to vertically upward. Since the ratios of the different magnetization directions of the ferromagnetic layers corresponding to the first storage unit on the left and the second storage unit on the left are different, the data storage states represented by the first storage unit on the left and the second storage unit on the left are different. By changing the energy generated by the energy assist device 41, the magnetic field strength of the coercive field of the magnetic moment of the multi-layer ferromagnetic layer 21 can be reduced, so that the magnetic field generating device can more easily flip the magnetization direction of the ferromagnetic layer 21, thereby utilizing the perpendicular magnetic anisotropy of the multi-layer ferromagnetic layer 21 to achieve data writing and multi-state storage of the storage unit. Figure 4 As shown, the magnetic field generating device generates a magnetic field in the in-plane direction and generates energy through the energy assisting device 41, thereby reducing the magnetic field strength of the coercive field of the magnetic moment in the second region, and changing the in-plane magnetization direction of the multilayer ferromagnetic layer 21 in the first region, thereby utilizing the in-plane magnetic anisotropy of the multilayer ferromagnetic layer 21 to realize data writing and polymorphic storage of the storage unit.

[0067] Thus, in terms of writing, the magnetic field writing head 40 includes two parts, one of which is a magnetic field generating part, i.e., a magnetic field generating device, which is used to generate a magnetic field in a vertical direction and / or in-plane direction in a first region, and the first region includes an action region of the energy assisting device 41. When the magnetic field generated by the magnetic field generating device cannot overcome the coercive field of the magnetic moment of the ferromagnetic layer 21, the energy assisting device 41 can be activated to reduce the coercive field of the magnetic moment of the adjacent extremely small region to below the magnetic field strength of the magnetic field generated by the magnetic field generating device, thereby realizing data writing to the adjacent ferromagnetic layer 21.

[0068] Optionally, the magnetic recording device further includes a controller configured to adjust the energy level of the energy assist device 41 according to the data to be written to flip the magnetization direction of the ferromagnetic layer 21 of the target number of layers when performing multi-state writing to the strip-shaped information storage layer 20 through the magnetic field write head 40.

[0069] In the disclosed embodiment, multi-state writing is performed on the strip information storage layer 20 by a magnetic field write head 40, including: starting a magnetic field generating device to generate a magnetic field, and starting an energy assist device 41 to reduce the magnetic field strength of the coercive field of the magnetic moment of the ferromagnetic layer 21 that needs to flip the magnetization direction.

[0070] In the embodiment of the present disclosure, the energy level of the energy assist device 41 is adjusted according to the data to be written to flip the magnetization direction of the target number of ferromagnetic layers 21, including: determining the target number of ferromagnetic layers 21 whose magnetization direction needs to be flipped according to the data to be written; determining the target energy level of the energy assist device 41 according to the target number of layers; and adjusting the energy level of the energy assist device 41 to the target energy level to flip the target number of ferromagnetic layers 21, thereby realizing polymorphic writing.

[0071] In this way, when writing is performed through the magnetic field write head 40, the range of the second area of ​​the energy assist device 41 can be changed by adjusting the energy level of the energy assist device 41, thereby flipping the magnetization direction of the ferromagnetic layer 21 in the second area, thereby realizing the polymorphic data writing of the strip information storage layer 20.

[0072] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. The embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A magnetic recording device, characterized in that include: a substrate comprising a base made of a flexible material; The strip-shaped information storage layer comprises a plurality of ferromagnetic layers made of ferromagnetic materials and a plurality of spacer layers made of non-magnetic materials; wherein the spacer layers are located between the ferromagnetic layers, and the ferromagnetic layers and the spacer layers are alternately stacked on the substrate.

2. The device according to claim 1, characterized in that The substrate further comprises: At least one coating layer is disposed on the lower surface of the substrate.

3. The device according to claim 1, characterized in that The magnetization direction of the ferromagnetic layer includes a perpendicular direction and / or an in-plane direction.

4. The device according to claim 1, characterized in that The strip information storage layer includes: A plurality of storage units, each storage unit being a strip-shaped information storage layer of a set length; Each storage unit represents the corresponding data storage state through the distribution ratio of the magnetization direction of the corresponding ferromagnetic layer.

5. The device according to claim 4, characterized in that The easy magnetization directions of the ferromagnetic layers of a single memory cell are the same.

6. The device according to any one of claims 1 to 5, characterized in that Also includes: At least one isolation layer is disposed between the substrate and the strip-shaped information storage layer to reduce the energy transferred to the substrate during the writing process.

7. The device according to any one of claims 1 to 5, characterized in that Also includes: At least one seed layer is disposed between the substrate and the strip-shaped information storage layer.

8. The device according to any one of claims 1 to 5, characterized in that Also includes: A magnetic field writing head includes a magnetic field generating device and an energy assisting device, wherein the magnetic field generating device is used to generate a vertical or in-plane magnetic field in a first region of a strip-shaped information storage layer, and the energy assisting device is used to reduce the magnetic field intensity of the coercive field of the magnetic moment in a second region of the strip-shaped information storage layer; wherein the first region includes the second region.

9. The device according to claim 8, characterized in that Also includes: The controller is configured to adjust the energy level of the energy assist device according to the data to be written when performing multi-state writing to the strip-shaped information storage layer through the magnetic field write head, so as to flip the magnetization direction of the ferromagnetic layer of the target number of layers.

10. A magnetic memory, characterized in that: include: A magnetic recording apparatus as claimed in any one of claims 1 to 9.

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