Track moment magnetic memory and preparation method thereof

Abstract

The invention provides an orbital moment magnetic memory and a preparation method thereof, the orbital moment magnetic memory comprises a substrate, an orbital Hall layer, a free layer, a barrier layer and a binding layer which are sequentially arranged from bottom to top, the orbital Hall layer comprises a metal layer and a FeMn layer which are arranged up and down, the free layer comprises a first Co2Fe6B2 layer and a Fe3GaTe2 layer which are arranged up and down, and the binding layer comprises a second Co2Fe6B2 layer and a second Fe3GaTe2 layer which are arranged up and down. And the bundling layer comprises a [Co / Pt] n layer, a Ta layer and a second Co2Fe6B2 layer which are arranged up and down. The structure utilizes the track Hall layer to efficiently generate a track flow, exchange a bias field and a stray field, and realizes spin polarization and magnetization flipping at the same time under low current through the strong spin-track coupling characteristic of the Fe3GaTe2 layer. According to the orbital moment magnetic memory, the power consumption is reduced while the relatively high writing speed is kept, the excellent performance is shown in high-speed data access, and basic support is provided for application in the fields of future orbital electronics, magnetic storage and the like.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor memory device technology, and in particular relates to an orbital magnetic memory and its preparation method. Background Technology

[0002] Currently, while spin-transfer torque (STT) magnetic memories have been widely used in various fields, their performance still suffers from several issues, such as high current density flowing through the barrier layer leading to short lifetimes. To address these problems, researchers have successfully fabricated spin-orbit torque (SOT) magnetic memories, which have garnered significant attention from both the scientific and industrial communities in recent years. The performance of SOT magnetic memories largely depends on the spin-orbit Hall channel material that generates the spin current. To achieve efficient charge-to-spin conversion, the spin-orbit Hall channel material needs to possess strong spin-orbit coupling (SOC). This not only limits the selection of spin-orbit Hall channel materials but also restricts the efficient control of the SOT effect. Recently, researchers have utilized a novel orbital Hall effect (OHE), and orbital torque (OT) devices based on the orbital Hall effect have demonstrated significant advantages in designing novel memory devices and efficiently controlling device performance. In orbital moment devices, the conversion of spin current depends on two stages: first, the orbital Hall effect converts charge current into orbital current through the orbital Hall channel material; then, the orbital current enters the adjacent ferromagnetic layer, where it is converted back into spin current through spin-orbit coupling, ultimately generating an orbital moment. Because the efficiency of the orbital moment depends on the performance of both the orbital Hall channel material and the ferromagnetic layer material, lower magnetization reversal current densities can be achieved. Furthermore, since the orbital Hall channel material is not limited to the spin-orbit coupling effect of the material, it offers a wider range of material choices, providing a promising solution for designing and realizing low-power orbital moment magnetic memory devices. Summary of the Invention

[0003] In view of this, the present invention aims to propose an orbital moment magnetic memory and its fabrication method. Through multilayer heterogeneous structure design and precise process control, the invention achieves the fabrication of an orbital moment magnetic memory with exchange bias, low power consumption and high storage density, while optimizing the device structure to improve read and write speed and reliability.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows: An orbital-moment magnetic memory (EMM) comprises, from bottom to top, a substrate, an orbital Hall layer, a free layer, a barrier layer, and a fixing layer. The orbital Hall layer includes a metal layer and an FeMn layer disposed vertically. The free layer includes a first Co₂Fe₆B₂ layer and an Fe₃GaTe₂ layer disposed vertically. The fixing layer includes [Co / Pt] layers disposed vertically.n The structure consists of a first layer, a Ta layer, and a second Co₂Fe₆B₂ layer; wherein, [Co / Pt] n The lower layer is a Co layer and the upper layer is a Pt layer, with n≥4, ensuring that electrons can tunnel through the barrier layer MgO between adjacent layers.

[0005] Among them, antiferromagnetic FeMn exhibits the orbital Hall effect, which achieves the conversion between orbital angular momentum and spin angular momentum by generating orbital currents. These orbital currents are converted into spin currents within the metallic layers (Pt and its alloys, Co and its alloys, Ni and its alloys, Fe and its alloys, Heusler alloys), thereby magnetizing and reversing the magnetic moment of the adjacent ferromagnetic free layer Fe3GaTe2. The exchange bias effect between antiferromagnetic FeMn and ferromagnetic Fe3GaTe2 allows for field-free magnetization reversal of the free layers without an external magnetic field. The Fe3GaTe2 / Co2Fe6B2 heterojunction utilizes the perpendicular anisotropy and two-dimensional properties of Fe3GaTe2 combined with the high spin polarizability mechanism of Co2Fe6B2 to achieve high magnetoresistivity characteristics. Simultaneously, [Co / Pt]... n The perpendicular magnetic anisotropy (PMA) of the multilayer film ensures the stable magnetic state of the nanoscale memory cells. The barrier layer design effectively improves write accuracy and reliability, reduces power consumption, and enhances thermal stability.

[0006] Furthermore, the substrate is any one of SiO2, MgO, and Al2O3, and the substrate thickness is 300 nm.

[0007] Furthermore, the thickness of the metal layer is 1-5 nm, and the metal layer is any one of Pt and its alloys, Co and its alloys, Ni and its alloys, Fe and its alloys, and Heusler alloys, and the thickness of the FeMn layer is 2-30 nm.

[0008] The FeMn layer is an antiferromagnetic layer that provides orbital current and exchange bias field, enabling efficient conversion of charge current to spin current and reducing magnetization reversal current density. At the same time, the exchange bias field can tilt the magnetic moment of the ferromagnetic layer, thereby achieving magnetization reversal without external field. The metal layer is a spin-orbit coupling layer that enhances spin polarization current efficiency and provides stray field, thereby reducing reversal current density and achieving magnetization reversal without external field assistance.

[0009] Specifically, FeMn can couple with Fe3GaTe2, thereby reducing the auxiliary external magnetic field during the magnetization reversal of Fe3GaTe2 and achieving a high magnetization reversal ratio. Therefore, using FeMn can reduce the magnitude of the auxiliary external magnetic field, enabling magnetization reversal of Fe3GaTe2 without an external magnetic field.

[0010] Using a FeMn / metal layer combination can reduce the magnetization reversal current density, thereby reducing power consumption.

[0011] The advantages of FeMn lie not only in itself, but also in the functional stacks formed with the upper and lower layers: 1) When used with the bottom electrode (such as Pt), it forms an orbital current amplifier.

[0012] Synergistic generation of orbital flow: Pt itself has a strong spin Hall effect, but a weak orbital Hall effect. FeMn (especially the Mn-rich phase) is the opposite. Combining the two, Pt can be used as a seed layer to optimize the crystal growth orientation of FeMn, while FeMn acts as the main force to generate high-purity orbital flow, achieving a "1+1>2" effect.

[0013] 2) When used in conjunction with a magnetic free layer (such as Fe3GaTe2), it enables efficient writing and field-free stability.

[0014] Efficient orbital moment injection: The strong orbital current generated by FeMn is efficiently converted into a spin current at the Fe3GaTe2 interface, driving its magnetization reversal. Since the orbital current efficiency is much higher than that of the conventional spin current, the critical current density required to reverse Fe3GaTe2 can be significantly reduced.

[0015] Induced exchange bias: Through interfacial coupling, FeMn can induce an exchange bias field in adjacent Fe3GaTe2 layers. This built-in field acts like a lock, fixing a magnetization direction to the lowest energy state, thus completely eliminating dependence on external auxiliary magnetic fields and achieving deterministic field-free flipping. This is a core function that simple heavy metals such as Pt cannot provide.

[0016] 3) With the top reference layer (e.g., [Co / Pt]) n Multilayer film) combination: to construct a complete MTJ (magnetic tunnel junction).

[0017] Furthermore, compared to other metals, such as CoCr and FeV, the OHE efficiency of Cr / V is significantly lower than that of Mn. In Co / Ni alloys, the strong spin polarization of ferromagnetic elements (Co / Ni) suppresses the orbital Hall contribution of the light metal. Cr and V alloys are prone to oxide formation or diffusion at the interface, which damages the interface quality. The high-temperature ordering process of NiMn exacerbates interfacial diffusion, making it uncontrollable. Therefore, FeMn performs better.

[0018] Furthermore, the thickness of the Fe3GaTe2 layer in the free layer is 3-20 nm, the thickness of the first Co2Fe6B2 layer is 0.8-1.5 nm, and the thickness of the second Co2Fe6B2 layer is the same as that of the first Co2Fe6B2 layer.

[0019] To improve device integration density, an out-of-plane ferromagnetic material with magnetocrystalline anisotropy is chosen. The two-dimensional magnetic layer Fe3GaTe2 exhibits strong magnetocrystalline anisotropy, enabling high-sensitivity magnetoresistance effects in smaller device sizes, and also possesses strong heat resistance and interference immunity. Furthermore, the two-dimensional properties of Fe3GaTe2 further reduce the energy and size required for the current-driven magnetic moment reversal of the device, making the MTJ of this invention suitable for non-volatile, low-power, high-density memory devices and orbital electronics applications. The Co2Fe6B2 layer is a heavy metal / ferromagnetic buffer layer that modulates the spin polarization of the ferromagnetic layer.

[0020] To ensure the magnetic and electronic properties and overall stability of the structure, Co2Fe6B2 with the same thickness is selected on both sides of the barrier layer. This ensures a symmetrical magnetic layer, uniform electron transport, and higher spin polarization of the ferromagnetic layer, thereby improving the overall performance of the device.

[0021] Furthermore, the barrier layer is made of MgO and has a thickness of 1-3 nm.

[0022] The barrier layer is the core structure for forming a magnetic tunnel junction.

[0023] Furthermore, the thickness of the second Co2Fe6B2 layer in the fixation layer is 0.8-1.5 nm, the thickness of the Ta layer is 0.8-1.3 nm, and the [Co / Pt] layer... n The Co layer has a thickness of 0.4 nm, and the Pt layer has a thickness of 0.8 nm.

[0024] The second Co2Fe6B2 layer, as part of the fixation layer, responds to changes in the external magnetic field; The Ta layer acts as a diffusion barrier layer, suppressing inter-diffusion of atoms at the interface; [Co / Pt] n The layers are vertically magnetically anisotropic multilayer films, constructing high-density storage cells. The strong spin-orbit coupling of platinum is utilized by alternately stacking Co and Pt. The heavy element effect of platinum (especially in the atomic structure of the Pt layer) significantly influences the magnetization direction. Cobalt has strong magnetism, but due to the spin-orbit effect of platinum, the magnetization tends to align along the normal direction of the film (i.e., perpendicular to the film surface), resulting in out-of-plane magnetization anisotropy. The spin-orbit coupling effect of Pt is crucial to the spin transport properties of the material.

[0025] Furthermore, a protective layer is included, located above the fixing layer. The protective layer is made of Pt or Au and has a thickness of 1.6 nm. The protective layer is used to improve the environmental stability of the device.

[0026] The present invention also provides a method for fabricating the orbital moment magnetic memory as described above, the method comprising the following steps: I. Using thin film fabrication technology, the materials of each layer are deposited on the substrate in the order from bottom to top, namely, the orbital Hall layer, the free layer, the barrier layer, the tethering layer (and the protective layer). II. The orbital magnetic memory is fabricated using micro-nano fabrication technology on the deposited film.

[0027] Furthermore, thin film fabrication processes include magnetron sputtering, molecular beam epitaxy, and mechanical exfoliation; micro / nano fabrication includes laser direct writing, electron beam lithography, and reactive ion beam etching.

[0028] Compared with existing technologies, the orbital moment magnetic storage device and its preparation method described in this invention have the following advantages: (1) The performance improvement of the track moment magnetic memory described in this invention is that the write power consumption is reduced by 1-2 orders of magnitude compared with the traditional STT / SOT-MRAM (magnetic random access memory).

[0029] (2) The orbital moment magnetic memory process described in this invention is simplified. By integrating magnetron sputtering and mechanical stripping, the high-temperature growth steps required for traditional epitaxial growth are reduced, saving energy consumption. At the same time, the micro-nano processing precision controls the device yield. Attached Figure Description

[0030] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the structure of the orbital moment magnetic storage device according to an embodiment of the present invention; Figure 2 The magnetization reversal performance of the orbital moment magnetic memory prepared in Example 1 is shown in (a) as the anomalous Hall resistance hysteresis loop; and (b) as the magnetoresistance (R) xy Relationship between (I) and current (I); Figure 3 The magnetization reversal performance of the orbital moment magnetic memory prepared in Example 2 is shown in (a) as the anomalous Hall resistance hysteresis loop; and (b) as the magnetoresistance (R0). xy Relationship between (I) and current (I); Figure 4 It is a traditional STT-MRAM structure; Figure 5 It is a traditional SOT-MRAM structure; Figure 6 To demonstrate the magnetization reversal performance of the orbital moment magnetic memory prepared in Comparative Example 3, (a) shows the anomalous Hall resistance hysteresis loop; (b) shows the magnetoresistance (R0). xy Relationship between (I) and current (I); Figure 7To illustrate the magnetization reversal performance of the orbital moment magnetic memory prepared in Comparative Example 4, (a) shows the anomalous Hall resistance hysteresis loop; (b) shows the magnetoresistance (R0). xy Relationship between (I) and current (I); Figure 8 To demonstrate the magnetization reversal performance of the orbital moment magnetic memory prepared in Comparative Example 5, (a) shows the anomalous Hall resistance hysteresis loop; (b) shows the magnetoresistance (R) xy Relationship between (I) and current (I); Figure 9 To demonstrate the magnetization reversal performance of the orbital moment magnetic memory prepared in Comparative Example 6, (a) shows the anomalous Hall resistance hysteresis loop; (b) shows the magnetoresistance (R0). xy Relationship between (I) and current (I); Figure 10 To demonstrate the magnetization reversal performance of the orbital moment magnetic memory prepared in Comparative Example 7, (a) shows the anomalous Hall resistance hysteresis loop; (b) shows the magnetoresistance (R0). xy The relationship between (I) and current (I) is shown in the graph.

[0031] Explanation of reference numerals in the attached figures: 1. Substrate; 2. Orbital Hall layer; 21. FeMn layer; 22. Metal layer; 3. Free layer; 31. Fe3GaTe2 layer; 32. First Co2Fe6B2 layer; 4. Barrier layer; 5. Fixing layer; 51. Second Co2Fe6B2 layer; 52. Ta layer; 53. [Co / Pt] n 6. Protective layer. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Example 1: Track-Modal Magnetic Storage like Figure 1 As shown, the orbital magnetic memory includes, from bottom to top, a substrate 1, an orbital Hall layer 2, a free layer 3, a barrier layer 4, a tethering layer 5, and a protective layer 6; Substrate 1 is made of SiO2 and has a thickness of 300 nm. The orbital Hall layer 2 includes a metal layer 22 and an FeMn layer 21 disposed on the top and bottom. The FeMn layer 21 has a thickness of 10 nm, and the metal layer 22 is a Pt layer with a thickness of 2 nm. The free layer 3 includes a first Co2Fe6B2 layer 32 and an Fe3GaTe2 layer 31 disposed on the top and bottom, respectively. The thickness of the Fe3GaTe2 layer 31 is 10 nm, and the thickness of the first Co2Fe6B2 layer 32 is 1 nm. Barrier layer 4 is an MgO layer with a thickness of 2 nm; The ligation layer 5 includes [Co / Pt] arranged sequentially from top to bottom. n Layer 53, Ta layer 52, and second Co2Fe6B2 layer 51, the second Co2Fe6B2 layer 51 has a thickness of 1 nm, the Ta layer 52 has a thickness of 1.3 nm, and [Co / Pt] n The thickness of layer 53 is 4.4 nm, and n=4.

[0035] The protective layer is a Pt layer with a thickness of 1.6 nm.

[0036] The above-mentioned method for fabricating a orbital moment magnetic memory includes the following steps: 1) First, FeMn and Pt layers are prepared sequentially by magnetron sputtering; 2) The Fe3GaTe2 layer was prepared by mechanical exfoliation and transfer; 3) Then, magnetron sputtering is used to sequentially prepare the first Co2Fe6B2 layer, the barrier layer, the second Co2Fe6B2 layer, the Ta layer, the [Co / Pt]4 layer and the protective layer; 4) Utilizing micro-nano fabrication technologies, such as laser direct writing, electron beam lithography, and reactive ion beam etching, to prepare materials such as... Figure 1 The track moment magnetic storage device shown.

[0037] Figure 2 The performance of the orbital moment magnetic memory prepared in this embodiment is demonstrated. In Figure (a), the curve is a "closed loop", indicating that the magnetoresistance of the device has a hysteresis effect with the change of magnetic field, reflecting the lag of the magnetic moment reversal inside the material, indicating that the orbital moment memory can be used for magnetization reversal testing. Figure (b) reflects the magnetoresistance behavior under the synergistic effect of current and magnetic field. Without an auxiliary magnetic field (0 Oe): the magnetoresistance changes little with the current (the curve is "flat"), and the magnetoresistance effect changes little, indicating that the current alone has little effect on the magnetoresistance. After applying a magnetic field: the curve is a "loop", and the stronger the magnetic field (e.g., 600 Oe), the larger the loop amplitude, indicating that the magnetic field enhances the magnetoresistance response to the current, reflecting the characteristic of "magnetic field-current synergistic reversal of magnetic moment".

[0038] Example 2 like Figure 1As shown, an orbital magnetic memory includes a substrate 1, an orbital Hall layer 2, a free layer 3, a barrier layer 4, a tethering layer 5, and a protective layer 6 arranged sequentially from bottom to top. Substrate 1 is made of SiO2 and has a thickness of 300 nm. The orbital Hall layer 2 includes a metal layer 22 and an FeMn layer 21 disposed on the top and bottom. The FeMn layer 21 has a thickness of 5nm, and the metal layer 22 is a Ni layer with a thickness of 1nm. The free layer 3 includes a first Co2Fe6B2 layer 32 and an Fe3GaTe2 layer 31 disposed on the top and bottom, respectively. The thickness of the Fe3GaTe2 layer 31 is 8 nm, and the thickness of the first Co2Fe6B2 layer 32 is 1.3 nm. Barrier layer 4 is an MgO layer with a thickness of 2 nm; The ligation layer 5 includes [Co / Pt] arranged sequentially from top to bottom. n Layer 53, Ta layer 52, and second Co2Fe6B2 layer 51, the second Co2Fe6B2 layer 51 has a thickness of 1.3 nm, the Ta layer 52 has a thickness of 0.8 nm, and [Co / Pt] n The thickness of layer 53 is 4.4 nm, and n=4; The protective layer is a Pt layer with a thickness of 1.6 nm.

[0039] The preparation method is the same as in Example 1.

[0040] The orbital magnetic memory device can be roughly considered as two parts: one is the magnetization reversal of the free layer, and the other is the fixed layer. If the magnetization reversal of the free layer can be combined with the fixed layer to form an OT-MRAM, a low-power orbital magnetic memory device can be realized. Therefore, the most important part of the orbital magnetic memory device is the FeMn / metal layer / Fe3GaTe2 / Co2Fe6B2 structure.

[0041] Figure 3 The performance of the orbital moment magnetic memory prepared in this embodiment is shown. (a) The curve is a "closed loop", indicating that the magnetoresistance of the device has a hysteresis effect with the change of magnetic field, reflecting the lag of the magnetic moment reversal inside the material, indicating that the orbital moment memory can be used for magnetization reversal testing. (b) The figure reflects the magnetoresistance behavior under the synergistic effect of current and magnetic field. Without an auxiliary magnetic field (0 Oe): the magnetoresistance changes little with the current (the curve is "flat"), and the magnetoresistance effect changes little, indicating that the current alone has little effect on the magnetoresistance; after applying a magnetic field: the curve is a "loop", and the stronger the magnetic field (e.g., 600 Oe), the larger the loop amplitude, indicating that the magnetic field enhances the magnetoresistance response to the current, reflecting the characteristic of "magnetic field-current synergistic reversal of magnetic moment".

[0042] from Figures 2-3As can be seen, both memory modules achieved magnetization reversal; applying opposite magnetic fields resulted in opposite magnetization reversal polarities, thus eliminating thermal effects. The resistivity of FeMn / Pt and Fe3GaTe2 / Co2Fe6B2 were measured using the IV method (calculation formula...). ρ=RS / L Then, by proportional current division, the magnetization reversal current density was calculated to be approximately 9 × 10⁻⁶. 6 A / cm 2 .

[0043] The magnetization reversal current density is approximately 9 × 10⁻⁶. 6 A / cm 2 It reduces the magnetization reversal current density (write power consumption) of three-dimensional ferromagnetic free layers by one to two orders of magnitude.

[0044] Comparative Example 1: Traditional STT-MRAM Its structure is as follows Figure 4 As shown, the STT is observed in the geometry at both ends, where a vertical current is injected through the MTJ (magnetic tunnel junction). Current tunneling through the barrier is spin-polarized, and due to the transfer of angular momentum, the free layer can undergo magnetization reversal when the current is large enough. The relative magnetization orientation of the free and tethered layers determines the device's resistance, which is monitored by tunnel magnetoresistance (TMR).

[0045] Comparative Example 2: Traditional SOT-MRAM Its structure is as follows Figure 5 As shown, SOT-MRAM is based on a three-terminal device, in which an additional conductive path is added near the free layer. Due to the spin Hall effect and / or the Rashba-Edelstein effect, the charge current flowing through this path causes a spin-polarized current to be injected into the free layer. In this device, SOT can switch the magnetization direction of the free layer without allowing current to pass through the MTJ tunnel barrier. At the cost of adding another terminal, the decoupling of the write and read current paths prevents write errors during read operations and reduces the risk of voltage breakdown.

[0046] In STT-MRAM, the magnetization reversal involves current passing through a barrier layer to change the magnetization direction of the free layer; however, excessive magnetization reversals can lead to failure. SOT-MRAM, on the other hand, does not require a barrier layer for magnetization reversal, ensuring device stability and reliability. However, SOT-MRAM requires a higher current density than in Example 1. Figure 2 The magnetization reversal current shown is 8.5 mA (~9 × 10⁻⁶). 6 A / cm 2 The current density is reduced by 1-2 orders of magnitude compared to traditional three-dimensional SOT-MRAM devices.

[0047] Comparative Example 3: The FeMn thickness is too thin. Compared to the structure in Example 1, the thickness of FeMn is 1 nm.

[0048] from Figure 6 (a) and Figure 6 (b) It can be seen that the R of this comparative proportion xy Between 17.4 and 18.6 Ω (a difference of approximately 1.2 Ω), the magnetoresistance change under zero field and the hysteresis loop change little under an auxiliary external magnetic field. However, power consumption is higher for the same magnetization reversal ratio.

[0049] Comparative Example 4: The FeMn thickness is too thick. Compared to the structure in Example 1, the thickness of FeMn is 35 nm.

[0050] Figure 7 (a) The hysteresis loop fluctuates greatly and is unstable (such as curve jumps and noise). The magnetoresistance changes abruptly with the magnetic field, reflecting that the magnetic moment reversal is disturbed and the magnetic stability is poor.

[0051] Figure 7 (b) Large and irregular curve fluctuations (such as "many spikes" in the 600Oe curve) indicate poor repeatability of the current-controlled magnetoresistive device, low device consistency, and "chaotic and inefficient" current-controlled magnetoresistive device (curve fluctuations). It may require a larger current to "cover" the fluctuations and result in higher power consumption.

[0052] Comparative Example 5: Replacement of FeMn Compared to the structure of Example 1, FeMn is replaced with Zr.

[0053] Figure 8 (a) Similarly, the hysteresis loop fluctuates violently and is discontinuous, resulting in poor magnetic stability.

[0054] Figure 8 (b) Large fluctuations and irregularities in the curve (such as "many spikes" in the 600Oe curve) reflect low efficiency and poor repeatability of the current-controlled magnetoresistive device, weak device consistency, "inefficient and chaotic" current-controlled magnetoresistive device, and higher power consumption.

[0055] Comparative Example 6: The thickness of Fe3GaTe2 is too thick. Compared to the structure in Example 1, the thickness of Fe3GaTe2 is 25 nm.

[0056] Figure 9 (a) explains that when the thickness of Fe3GaTe2 is too large, the magnetic easy axis is deflected from out-of-plane to in-plane, resulting in a small coercivity and poor stability.

[0057] Figure 9 (b) The curves show obvious fluctuations under certain magnetic fields (such as -600Oe, -500Oe, etc.), indicating that the process of current-controlled magnetoresistive control is more affected by interference, resulting in poor performance repeatability and stability, and relatively higher power consumption.

[0058] Comparative Example 7: FeMn replaced with pure Pt Compared to the structure of Example 1, FeMn is replaced with pure Pt.

[0059] from Figure 10 It can be seen that (a) has a better hysteresis loop, but its coercivity is too large, and the required magnetization reversal current is also larger. (b) has a special curve shape (such as the -500Oe curve is a "rectangular loop"), and the magnetoresistance-current response under different magnetic fields is very different. It reflects that the current-controlled magnetoresistance mode changes drastically with the magnetic field. It only has a stable rectangular loop under a specific magnetic field (such as -500Oe), and has high power consumption and poor versatility.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A racetrack memory, comprising: The track moment magnetic memory comprises, from bottom to top, a substrate, a track Hall layer, a free layer, a barrier layer and a pinned layer, the track Hall layer comprises a metal layer and a FeMn layer arranged in a top-bottom manner, the free layer comprises a first Co2Fe6B2 layer and a Fe3GaTe2 layer arranged in a top-bottom manner, and the pinned layer comprises, from top to bottom, a [Co / Pt] n layer, a Ta layer and a second Co2Fe6B2 layer; wherein the lower layer of the [Co / Pt] n layer is a Co layer, the upper layer is a Pt layer, and n is greater than or equal to 4.

2. The orbital angular momentum magnetic memory of claim 1, wherein: The substrate is any one of SiO2, MgO, Al2O3.

3. The orbital angular momentum magnetic memory of claim 1, wherein: The thickness of the metal layer is 1-5nm, and the metal layer is any one of Pt and its alloy, Co and its alloy, Ni and its alloy, Fe and its alloy, Heusler alloy; the thickness of the FeMn layer is 2-30nm.

4. The orbital angular momentum magnetic memory of claim 1, wherein: The thickness of the Fe3GaTe2 layer in the free layer is 3-20nm, the thickness of the first Co2Fe6B2 layer is 0.8-1.5nm, and the thickness of the second Co2Fe6B2 layer is the same as that of the first Co2Fe6B2 layer.

5. The orbital angular momentum magnetic memory of claim 1, wherein: The material of the barrier layer is MgO, and the thickness is 1-3nm.

6. The orbital angular momentum magnetic memory of claim 1, wherein: The thickness of the second Co2Fe6B2 layer in the pinned layer is 0.8-1.5 nm, the thickness of the Ta layer is 0.8-1.3 nm, the thickness of the Co layer in the [Co / Pt] n The thickness of the Co layer is 0.4 nm, and the thickness of the Pt layer is 0.8 nm.

7. The orbital angular momentum magnetic memory of claim 1, wherein: The method further comprises a protective layer, the protective layer is located above the pinned layer, the material of the protective layer is Pt or Au, and the thickness is 1.6nm.

8. A method of fabricating a track perpendicular magnetic memory as claimed in any one of claims 1-7, characterized in that: The method comprises the following steps: I. Depositing each layer of material on the substrate in the order from bottom to top by a thin film preparation process, which is in turn an orbit Hall layer, a free layer, a barrier layer, and a pinned layer; II. Preparing an orbit matrix magnetic memory by micro-nano processing technology on the deposited film layer.

9. The method of claim 8, wherein: The thin film preparation process comprises magnetron sputtering, molecular beam epitaxy, and mechanical peeling; the micro-nano processing technology comprises laser direct writing, electron beam lithography, and reactive ion beam etching.

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