A magnetic storage unit and its preparation method, and magnetic storage

Abstract

The present invention discloses a method for preparing a magnetic storage unit. The method comprises the following steps: on the surface of a preset spin-orbit moment metal matrix precursor, a magnetic free layer, an insulating tunnel layer, a magnetic reference layer, and a mask layer are sequentially arranged outwardly to obtain a unit to be etched; the mask layer, the magnetic reference layer, the insulating tunnel layer, and the magnetic free layer are etched to obtain an etched workpiece including a columnar epitaxial layer; a protective layer is arranged on the surface of the etched workpiece; the spin-orbit moment metal matrix precursor after the protective layer is arranged is subjected to a directional oxygen ion treatment; the peripheral oxide layer is subjected to surface reduction; and the protective layer above the mask layer of the storage unit precursor is removed to obtain a magnetic storage unit. The present invention avoids the problem of poor thickness uniformity of the spin-orbit moment metal matrix directly produced to a target thickness in the prior art. The present invention also provides a magnetic storage unit and a magnetic memory having the above-mentioned beneficial effects.

Description

Technical Field

[0001] The present invention relates to the field of storage technology, and in particular to a magnetic storage unit, a preparation method thereof, and a magnetic memory. Background Art

[0002] Compared to traditional STT-MRAM (spin transfer torque magnetic random access memory), SOT-MRAM (spin orbit torque magnetic random access memory) not only maintains the excellent characteristics of MRAM such as high speed and low power consumption, but also achieves low write voltage and read-write path separation. It is expected to replace STT-MRAM and use spin-orbit torque to achieve fast and reliable magnetization reversal. However, in spin-orbit magnetic memory based on MTJ (magnetic tunnel junction), the free layer is in direct contact with the spin-orbit torque supply line. However, it should be noted that since the current passing through it will directly control the storage unit on it, the surface flatness of the ultra-thin spin-orbit torque material is extremely high. Excessive thickness deviations at different locations will lead to different internal currents, which in turn will reduce the reliability of the storage device.

[0003] However, in the prior art, processes such as etching and chemical mechanical polishing during device preparation will inevitably affect the spin-orbit moment metal matrix, further increasing the non-uniformity of the spin-orbit moment metal matrix.

[0004] Therefore, how to find a method to ensure the uniformity of the thickness of the spin-orbit moment metal matrix is ​​an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a magnetic storage unit and a preparation method thereof, and a magnetic memory, so as to solve the problem of poor thickness uniformity of a spin-orbit moment metal matrix in the prior art.

[0006] To solve the above technical problems, the present invention provides a method for preparing a magnetic storage unit, comprising:

[0007] On the surface of a preset spin-orbit moment metal substrate precursor, a magnetic free layer, an insulating tunnel layer, a magnetic reference layer and a mask layer are sequentially arranged outward to obtain a unit to be etched;

[0008] Etching the mask layer, the magnetic reference layer, the insulating tunnel layer, and the magnetic free layer to obtain an etched workpiece including a columnar epitaxial layer;

[0009] providing a protective layer on the surface of the etched workpiece;

[0010] Performing a directional oxygen ion treatment on the spin-orbit moment metal matrix precursor after the protective layer is provided, so as to oxidize the spin-orbit moment metal matrix precursor located in the columnar peripheral region into a peripheral oxide layer;

[0011] Performing surface reduction on the peripheral oxide layer to reduce the peripheral oxide layer of target thickness close to the columnar epitaxial layer into a spin-orbit moment metal matrix to obtain a memory cell preset;

[0012] The protective layer above the mask layer of the memory cell preset is removed to obtain a magnetic memory cell.

[0013] Optionally, in the method for preparing the magnetic storage unit, before the directional oxygen ion treatment is performed on the spin-orbit moment metal matrix precursor after the protective layer is provided, the method further comprises:

[0014] The protective layer on the surface of the spin-orbit moment metal substrate precursor is removed, and the protective layer on the side wall of the columnar epitaxial layer is retained.

[0015] Optionally, in the method for preparing the magnetic storage unit, before providing the protective layer on the surface of the etching workpiece, the method further comprises:

[0016] Physically cleaning the sidewalls of the columnar epitaxial layer.

[0017] Optionally, in the method for preparing the magnetic storage unit, the physical cleaning includes plasma cleaning or ion beam etching.

[0018] Optionally, in the method for preparing the magnetic storage unit, the protective layer is provided on the surface of the etched workpiece by any one of sputtering deposition, ion beam deposition, chemical vapor deposition, and atomic layer deposition.

[0019] A magnetic storage unit comprises, from bottom to top, a metal base, a spin-orbit moment metal matrix, a columnar epitaxial layer and a protective layer;

[0020] The metal base includes a peripheral oxide layer located in the columnar peripheral region and a central metal layer located in the columnar region;

[0021] The columnar epitaxial layer includes, from bottom to top, a magnetic free layer, an insulating tunnel layer, a magnetic reference layer and a mask layer;

[0022] The protection layer is arranged on the side surface of the columnar epitaxial layer and the upper surface of the spin-orbit moment metal substrate.

[0023] Optionally, in the magnetic storage unit, the protective layer is any one of a silicon nitride layer, a silicon oxide layer or a silicon oxynitride layer.

[0024] Optionally, in the magnetic storage unit, the spin-orbit moment metal matrix is ​​a matrix of platinum, tungsten, gold, molybdenum or tantalum metal.

[0025] Optionally, in the magnetic storage unit, the thickness of the spin-orbit moment metal matrix ranges from 1 nanometer to 10 nanometers, including end points.

[0026] A magnetic memory comprises any one of the magnetic storage units described above.

[0027] The present invention provides a method for preparing a magnetic storage unit, comprising the steps of: arranging a magnetic free layer, an insulating tunnel layer, a magnetic reference layer, and a mask layer outwardly on the surface of a preset spin-orbit moment metal matrix precursor in sequence to obtain a unit to be etched; etching the mask layer, the magnetic reference layer, the insulating tunnel layer, and the magnetic free layer to obtain an etched workpiece including a columnar epitaxial layer; arranging a protective layer on the surface of the etched workpiece; performing a directional oxygen ion treatment on the spin-orbit moment metal matrix precursor after the protective layer is provided to oxidize the spin-orbit moment metal matrix precursor located in a columnar peripheral region into a peripheral oxide layer; performing surface reduction on the peripheral oxide layer to reduce the peripheral oxide layer of a target thickness close to one side of the columnar epitaxial layer to the spin-orbit moment metal matrix to obtain a storage unit precursor; and removing the protective layer above the mask layer of the storage unit precursor to obtain a magnetic storage unit.

[0028] Unlike the prior art, which directly sets an epitaxial layer on a spin-orbit moment metal substrate of target thickness, the present invention sets an epitaxial layer on the surface of a spin-orbit moment metal substrate precursor of excess thickness, then oxidizes the excessively thick spin-orbit moment metal substrate precursor (equivalent to insulation), and finally reduces the oxidized peripheral oxide layer, reducing the peripheral oxide layer located on the upper surface to a metal layer with high conductivity. Since the conditions of the surface reduction reaction are controllable and the reaction rate is adjustable, the thickness of the metal layer obtained by the final reduction can be precisely controlled. The metal layer obtained after reduction and the unoxidized metal layer located below the columnar epitaxial layer constitute a spin-orbit moment metal substrate of target thickness. Since the spin-orbit moment metal substrate in the present invention is generated after etching and polishing the epitaxial layer, it will not be affected by etching and polishing. At the same time, using the spin-orbit moment metal substrate precursor of excess thickness as a growth substrate also avoids the problem of poor thickness uniformity of the spin-orbit moment metal substrate directly produced at the target thickness in the prior art. The present invention also provides a magnetic storage unit and a magnetic memory having the above beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 A schematic diagram of the connection structure between the magnetic storage unit and the external circuit when the magnetic storage unit is working;

[0031] Figure 2 A schematic flow chart of a specific embodiment of a method for preparing a magnetic storage unit provided by the present invention;

[0032] Figure 3 A schematic flow chart of another specific embodiment of the method for preparing a magnetic storage unit provided by the present invention;

[0033] Figures 4 to 7 An intermediate process flow chart of a specific embodiment of the method for preparing a magnetic storage unit provided by the present invention;

[0034] Figure 8 This is a structural schematic diagram of a specific embodiment of the magnetic storage unit provided by the present invention. DETAILED DESCRIPTION

[0035] The connection method between the magnetic storage unit and the external circuit is as follows Figure 1 As shown, the first port of the magnetic storage unit is connected to the drain of the write word line transistor, the second port is connected to the bit line, and the third port is connected to the drain of the read word line transistor. The source of the read word line transistor and the source of the write word line transistor are connected to the source line.

[0036] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0037] The core of the present invention is to provide a method for preparing a magnetic storage unit, a flow chart of a specific embodiment of the invention is shown as follows: Figure 2 As shown, it is called specific implementation method one, including:

[0038] S101: On the surface of a preset spin-orbit moment metal substrate precursor 10, a magnetic free layer 20, an insulating tunnel layer 30, a magnetic reference layer 40 and a mask layer 50 are sequentially arranged outward to obtain a unit to be etched.

[0039] S102 : etching the mask layer 50 , the magnetic reference layer 40 , the insulating tunnel layer 30 , and the magnetic free layer 20 to obtain an etched workpiece including a columnar epitaxial layer.

[0040] The structural diagram of the columnar epitaxy on the spin-orbit moment metal substrate 12 after step S102 is shown in FIG. Figure 4 shown.

[0041] S103: providing a protective layer 60 on the surface of the etched workpiece.

[0042] The structure of the etching workpiece provided with the protective layer 60 is also shown in FIG. Figure 5 shown.

[0043] As a preferred embodiment, before providing the protective layer 60 on the surface of the etched workpiece, the method further includes:

[0044] The sidewalls of the columnar epitaxial layer are physically cleaned to repair damage near the tunnel junction and prevent irregular edges of the columnar epitaxial layer or residual chemical from affecting the setting of the protective layer 60 during the etching process. Furthermore, the physical cleaning includes plasma cleaning or ion beam etching.

[0045] Furthermore, the protective layer 60 is disposed on the surface of the etched workpiece by any one of sputtering deposition, ion beam deposition, chemical vapor deposition, and atomic layer deposition. Of course, other disposition methods may also be selected according to actual conditions.

[0046] S104 : performing directional oxygen ion treatment on the spin-orbit moment metal matrix precursor 10 after the protective layer 60 is provided, so as to oxidize the spin-orbit moment metal matrix precursor 10 located in the columnar peripheral region into a peripheral oxide layer 11 .

[0047] The columnar peripheral region refers to a region not below the columnar epitaxial layer but outside the projection region of the columnar epitaxial layer on the spin-orbit moment metal substrate precursor 10. For details, please refer to Figure 6 , Figure 6 The area not located below the columnar epitaxial layer is the columnar peripheral area. Of course, in actual production, the peripheral oxide layer 11 may partially extend below the columnar epitaxial layer, which has little effect on the beneficial effects of the present invention.

[0048] S105: performing surface reduction on the peripheral oxide layer 11 so that the peripheral oxide layer 11 with a target thickness close to the columnar epitaxial layer is reduced to a spin-orbit moment metal matrix 12, thereby obtaining a memory cell preset.

[0049] The surface reduction refers to reducing the upper surface of the spin-orbit moment metal matrix 12 (ie, the surface close to the columnar epitaxial layer). Specifically, the reduction reaction can be performed by hydrogen.

[0050] The structural diagram of the workpiece after restoration is as follows Figure 7As shown, the reduced metal layer located in the columnar peripheral region and the unoxidized metal layer located below the columnar epitaxial layer together constitute the spin-orbit moment metal matrix 12 .

[0051] S106: removing the protective layer 60 above the mask layer 50 of the memory cell pre-deposition to obtain a magnetic memory cell.

[0052] The present invention provides a method for preparing a magnetic storage unit, comprising the steps of: providing a magnetic free layer 20, an insulating tunnel layer 30, a magnetic reference layer 40, and a mask layer 50 outwardly on the surface of a preset spin-orbit moment metal matrix precursor 10, thereby obtaining a unit to be etched; etching the mask layer 50, the magnetic reference layer 40, the insulating tunnel layer 30, and the magnetic free layer 20 to obtain an etched workpiece including a columnar epitaxial layer; providing a protective layer 60 on the surface of the etched workpiece; subjecting the spin-orbit moment metal matrix precursor 10 after providing the protective layer 60 to a directional oxygen ion treatment to oxidize the spin-orbit moment metal matrix precursor 10 located in a columnar peripheral region into a peripheral oxide layer 11; performing surface reduction on the peripheral oxide layer 11 to reduce the peripheral oxide layer 11 of a target thickness close to the columnar epitaxial layer to a spin-orbit moment metal matrix 12, thereby obtaining a storage unit precursor; and removing the protective layer 60 above the mask layer 50 of the storage unit precursor to obtain a magnetic storage unit. Unlike the prior art in which an epitaxial layer is directly arranged on a spin-orbit moment metal substrate 12 of target thickness, the present invention arranges an epitaxial layer on the surface of a spin-orbit moment metal substrate precursor 10 of excess thickness, then oxidizes the over-thick spin-orbit moment metal substrate precursor 10 (equivalent to insulation), and finally reduces the oxidized peripheral oxide layer 11, and reduces the peripheral oxide layer 11 located on the upper surface to a metal layer with high conductivity. Since the conditions of the surface reduction reaction are controllable and the reaction rate is adjustable, the thickness of the metal layer finally reduced can be precisely controlled. The metal layer obtained after reduction and the unoxidized metal layer located below the columnar epitaxial layer constitute a spin-orbit moment metal substrate 12 of target thickness. Since the spin-orbit moment metal matrix 12 in the present invention is generated after the etching and polishing of the epitaxial layer, it will not be affected by the etching and polishing. At the same time, using the spin-orbit moment metal matrix precursor 10 of excess thickness as the growth substrate also avoids the problem of poor thickness uniformity of the spin-orbit moment metal matrix 12 directly produced with the target thickness in the prior art.

[0053] On the basis of the first embodiment, the protected layer 60 is further treated before the directional oxygen treatment to obtain the second embodiment, the flow diagram of which is as follows: Figure 3 Shown, including:

[0054] S201: On the surface of a preset spin-orbit moment metal matrix precursor 10, a magnetic free layer 20, an insulating tunnel layer 30, a magnetic reference layer 40 and a mask layer 50 are sequentially arranged outwards to obtain a unit to be etched.

[0055] S202 : etching the mask layer 50 , the magnetic reference layer 40 , the insulating tunnel layer 30 , and the magnetic free layer 20 to obtain an etched workpiece including a columnar epitaxial layer.

[0056] S203: providing a protective layer 60 on the surface of the etched workpiece.

[0057] S204: removing the protective layer 60 on the surface of the spin-orbit moment metal substrate precursor 10 and retaining the protective layer 60 on the sidewall of the columnar epitaxial layer.

[0058] S205 : performing directional oxygen ion treatment on the spin-orbit moment metal matrix precursor 10 after the protective layer 60 is provided, so as to oxidize the spin-orbit moment metal matrix precursor 10 located in the columnar peripheral region into a peripheral oxide layer 11 .

[0059] S206: performing surface reduction on the peripheral oxide layer 11 so that the peripheral oxide layer 11 with a target thickness close to the columnar epitaxial layer is reduced to a spin-orbit moment metal matrix 12, thereby obtaining a memory cell preset.

[0060] S207: removing the protective layer 60 above the mask layer 50 of the memory cell pre-deposition to obtain a magnetic memory cell.

[0061] In this specific embodiment, before the etched workpiece with the protective layer 60 is subjected to the directional oxygen treatment, the protective layer 60 on the surface of the spin-orbit moment metal matrix precursor 10 (i.e., the columnar peripheral area) is first removed, so that the upper surface of the spin-orbit moment metal matrix precursor 10 located in the columnar peripheral area is directly exposed, so that the subsequent directional oxygen treatment is faster, more sufficient, and more uniform, while improving the production efficiency. At the same time, the quality of the spin-orbit moment metal matrix 12 of the final product is improved. The structural schematic diagram of the magnetic storage unit corresponding to this specific embodiment can be referred to. Figure 8 .

[0062] The present invention also provides a magnetic storage unit, a structural diagram of a specific embodiment of which is shown in FIG. Figure 8 As shown, it is called the third embodiment, which includes, from bottom to top, a metal base, a spin-orbit moment metal base 12, a columnar epitaxial layer and a protective layer 60;

[0063] The metal base includes a peripheral oxide layer 11 located in the columnar peripheral region and a central metal layer located in the columnar region;

[0064] The columnar epitaxial layer includes, from bottom to top, a magnetic free layer 20, an insulating tunnel layer 30, a magnetic reference layer 40 and a mask layer 50;

[0065] The protection layer 60 is disposed on the side surfaces of the columnar epitaxial layer and the upper surface of the spin-orbit moment metal substrate 12 .

[0066] As a preferred embodiment, the protective layer 60 is any one of a silicon nitride layer, a silicon oxide layer or a silicon oxynitride layer. Of course, it can also be adjusted accordingly according to actual needs.

[0067] In addition, the spin-orbit moment metal substrate 12 is a substrate of platinum, tungsten, gold, molybdenum or tantalum metal. Of course, other materials can also be selected according to actual needs.

[0068] Furthermore, the thickness of the spin-orbit moment metal matrix 12 ranges from 1 nm to 10 nm, including endpoint values ​​such as 1.0 nm, 5.0 nm or 10.0 nm; the thickness of the magnetic free layer 20 ranges from 1 nm to 5 nm, including endpoint values ​​such as 1.0 nm, 3.2 nm or 5.0 nm.

[0069] The magnetic storage unit provided by the present invention includes, from bottom to top, a metal base, a spin-orbit moment metal substrate 12, a columnar epitaxial layer and a protective layer 60; the metal base includes a peripheral oxide layer 11 located in the columnar peripheral area and a central metal layer located in the columnar area; the columnar epitaxial layer includes, from bottom to top, a magnetic free layer 20, an insulating tunnel layer 30, a magnetic reference layer 40 and a mask layer 50; the protective layer 60 is arranged on the side surface of the columnar epitaxial layer and the upper surface of the spin-orbit moment metal substrate 12. Unlike the prior art in which an epitaxial layer is directly arranged on a spin-orbit moment metal substrate 12 of target thickness, the present invention arranges an epitaxial layer on the surface of a spin-orbit moment metal substrate precursor 10 of excess thickness, then oxidizes the over-thick spin-orbit moment metal substrate precursor 10 (equivalent to insulation), and finally reduces the oxidized peripheral oxide layer 11, and reduces the peripheral oxide layer 11 located on the upper surface to a metal layer with high conductivity. Since the conditions of the surface reduction reaction are controllable and the reaction rate is adjustable, the thickness of the metal layer finally reduced can be precisely controlled. The metal layer obtained after reduction and the unoxidized metal layer located below the columnar epitaxial layer constitute a spin-orbit moment metal substrate 12 of target thickness. Since the spin-orbit moment metal matrix 12 in the present invention is generated after the etching and polishing of the epitaxial layer, it will not be affected by the etching and polishing. At the same time, using the spin-orbit moment metal matrix precursor 10 of excess thickness as the growth substrate also avoids the problem of poor thickness uniformity of the spin-orbit moment metal matrix 12 directly produced with the target thickness in the prior art.

[0070] The present invention also provides a magnetic memory having the above beneficial effects, wherein the magnetic memory comprises any one of the magnetic storage units described above. The present invention provides a method for preparing a magnetic storage unit, comprising the steps of: providing a magnetic free layer 20, an insulating tunnel layer 30, a magnetic reference layer 40, and a mask layer 50 outwardly on the surface of a preset spin-orbit moment metal matrix precursor 10, thereby obtaining a unit to be etched; etching the mask layer 50, the magnetic reference layer 40, the insulating tunnel layer 30, and the magnetic free layer 20 to obtain an etched workpiece including a columnar epitaxial layer; providing a protective layer 60 on the surface of the etched workpiece; subjecting the spin-orbit moment metal matrix precursor 10 after providing the protective layer 60 to a directional oxygen ion treatment to oxidize the spin-orbit moment metal matrix precursor 10 located in a columnar peripheral region into a peripheral oxide layer 11; performing surface reduction on the peripheral oxide layer 11 to reduce the peripheral oxide layer 11 of a target thickness close to the columnar epitaxial layer to a spin-orbit moment metal matrix 12, thereby obtaining a storage unit precursor; and removing the protective layer 60 above the mask layer 50 of the storage unit precursor to obtain a magnetic storage unit. Unlike the prior art in which an epitaxial layer is directly arranged on a spin-orbit moment metal substrate 12 of target thickness, the present invention arranges an epitaxial layer on the surface of a spin-orbit moment metal substrate precursor 10 of excess thickness, then oxidizes the over-thick spin-orbit moment metal substrate precursor 10 (equivalent to insulation), and finally reduces the oxidized peripheral oxide layer 11, and reduces the peripheral oxide layer 11 located on the upper surface to a metal layer with high conductivity. Since the conditions of the surface reduction reaction are controllable and the reaction rate is adjustable, the thickness of the metal layer finally reduced can be precisely controlled. The metal layer obtained after reduction and the unoxidized metal layer located below the columnar epitaxial layer constitute a spin-orbit moment metal substrate 12 of target thickness. Since the spin-orbit moment metal matrix 12 in the present invention is generated after the etching and polishing of the epitaxial layer, it will not be affected by the etching and polishing. At the same time, using the spin-orbit moment metal matrix precursor 10 of excess thickness as the growth substrate also avoids the problem of poor thickness uniformity of the spin-orbit moment metal matrix 12 directly produced with the target thickness in the prior art.

[0071] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. Reference can be made to the descriptions of the identical or similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions of the methods.

[0072] It should be noted that, in this specification, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0073] The magnetic storage unit, its preparation method, and magnetic memory provided by the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is intended only to facilitate understanding of the method and core concepts of the present invention. It should be noted that those skilled in the art may make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a magnetic storage unit, characterized in that: include: On the surface of a preset spin-orbit moment metal substrate precursor, a magnetic free layer, an insulating tunnel layer, a magnetic reference layer and a mask layer are sequentially arranged outward to obtain a unit to be etched; Etching the mask layer, the magnetic reference layer, the insulating tunnel layer, and the magnetic free layer to obtain an etched workpiece including a columnar epitaxial layer; providing a protective layer on the surface of the etched workpiece; Performing a directional oxygen ion treatment on the spin-orbit moment metal matrix precursor after the protective layer is provided, so as to oxidize the spin-orbit moment metal matrix precursor located in the columnar peripheral region into a peripheral oxide layer; Performing surface reduction on the peripheral oxide layer to reduce the peripheral oxide layer of target thickness close to the columnar epitaxial layer into a spin-orbit moment metal matrix to obtain a memory cell preset; The protective layer above the mask layer of the memory cell preset is removed to obtain a magnetic memory cell.

2. The method for preparing a magnetic storage unit according to claim 1, wherein: Before the directional oxygen ion treatment is performed on the spin-orbit moment metal substrate precursor after the protective layer is provided, the method further includes: The protective layer on the surface of the spin-orbit moment metal substrate precursor is removed, and the protective layer on the side wall of the columnar epitaxial layer is retained.

3. The method for preparing a magnetic storage unit according to claim 1, wherein: Before providing a protective layer on the surface of the etched workpiece, the method further comprises: Physically cleaning the sidewalls of the columnar epitaxial layer.

4. The method for preparing a magnetic storage unit according to claim 3, wherein: The physical cleaning includes plasma cleaning or ion beam etching.

5. The method for preparing a magnetic storage unit according to claim 1, wherein: The protective layer is disposed on the surface of the etched workpiece by any one of sputtering deposition, ion beam deposition, chemical vapor deposition, and atomic layer deposition.

6. A magnetic storage unit, characterized in that The magnetic storage unit is a storage unit obtained by the method for preparing a magnetic storage unit according to any one of claims 1 to 5, and comprises, from bottom to top, a metal base, a spin-orbit moment metal matrix, and a columnar epitaxial layer; The metal base includes a peripheral oxide layer located in the columnar peripheral region and a central metal layer located in the columnar region; The columnar epitaxial layer includes, from bottom to top, a magnetic free layer, an insulating tunnel layer, a magnetic reference layer and a mask layer; The magnetic storage unit further includes a protective layer; The protection layer is arranged on the side surface of the columnar epitaxial layer and the upper surface of the spin-orbit moment metal substrate.

7. The magnetic storage unit according to claim 6, wherein The protective layer is any one of a silicon nitride layer, a silicon oxide layer or a silicon oxynitride layer.

8. The magnetic storage unit according to claim 6, wherein The spin-orbit moment metal matrix is ​​a matrix of platinum, tungsten, gold, molybdenum or tantalum metal.

9. The magnetic storage unit according to claim 6, wherein: The spin-orbit moment metal matrix has a thickness ranging from 1 nanometer to 10 nanometers, inclusive.

10. A magnetic memory, characterized in that: The magnetic memory comprises the magnetic storage unit according to any one of claims 6 to 9.

Images