A track perpendicular magnetic memory and a preparation method thereof

Abstract

This invention provides an orbital moment magnetic memory and its fabrication method. The orbital moment magnetic memory includes, 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 arranged vertically. The free layer includes a first Co2Fe6B2 layer and an Fe3GaTe2 layer arranged vertically. The fixing layer includes a [Co / Pt] layer arranged vertically. n The structure consists of a first layer, a Ta layer, and a second Co2Fe6B2 layer. This structure utilizes the orbital Hall layer to efficiently generate orbital current, exchange bias field, and stray field, and leverages the strong spin-orbit coupling characteristics of the Fe3GaTe2 layer to achieve spin polarization and magnetization reversal at low current. This orbital-moment magnetic memory not only maintains a fast write speed while reducing power consumption, but also exhibits superior performance in high-speed data access, providing fundamental support for future applications in orbital electronics, magnetic storage, and other fields.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor memory devices, and particularly relates to a track moment magnetic memory and a preparation method thereof. BACKGROUND

[0002] At present, although spin transfer torque (STT) magnetic memory has been applied to various fields as a main magnetic memory, its performance still has many problems, such as short service life caused by high current density flowing through the barrier layer of the device. In order to solve the problems of high power consumption and short service life of the STT magnetic memory, researchers successfully prepared a spin-orbit torque (SOT) magnetic memory, which has received extensive attention from the scientific research and industrial communities in recent years. The performance of the SOT magnetic memory mainly depends on the spin-orbit Hall channel material for generating spin current. In order to realize efficient charge flow-spin flow conversion, the spin-orbit Hall channel material needs to have strong spin-orbit coupling (SOC). This not only limits the selection of the spin-orbit Hall channel material, but also limits the efficient regulation of the SOT effect. Recently, researchers use a new orbital Hall effect (OHE), and the orbital moment (OT) device based on the orbital Hall effect shows great advantages in designing new memory devices and efficiently regulating device performance. In the orbital moment device, the conversion of spin current depends on two stages: first, the orbital Hall effect converts the charge flow into orbital flow through the orbital Hall channel material; then, the orbital flow enters the adjacent ferromagnetic layer, and the orbital flow is converted into spin current through the spin-orbit coupling of the ferromagnetic layer, and finally the orbital moment is generated. Because the efficiency of the orbital moment depends on the performance of the orbital Hall channel material and the ferromagnetic layer material, a lower magnetization reversal current density can be realized. In addition, because the orbital Hall channel material is not limited to the spin-orbit coupling effect of the material, because of the wider selection of materials, it provides a promising solution for designing and realizing low-power orbital moment magnetic memory devices. SUMMARY

[0003] Therefore, the present application aims to provide a track moment magnetic memory and a preparation method thereof, which realizes the preparation of the track moment magnetic memory with exchange bias, low power consumption and high storage density through multi-layer heterostructure design and precise process control, and optimizes the device structure to improve the read-write speed and reliability.

[0004] To achieve the above object, the technical scheme of the present application is as follows:

[0005] A track moment magnetic memory, comprising, from bottom to top, a substrate, a track Hall layer, a free layer, a barrier layer, a pinned layer, the track Hall layer comprising a metal layer and a FeMn layer arranged in a top-bottom manner, the free layer comprising a first Co2Fe6B2 layer and a Fe3GaTe2 layer arranged in a top-bottom manner, the pinned layer comprising a [Co / Pt] n layer, a Ta layer and a second Co2Fe6B2 layer arranged in a top-bottom manner; wherein the lower layer of the [Co / Pt] n layer is a Co layer and the upper layer is a Pt layer, n is greater than or equal to 4, and the adjacent two layers can tunnel electrons through the barrier layer MgO.

[0006] The antiferromagnetic FeMn has a track Hall effect, which realizes the conversion between the orbital angular momentum and the spin angular momentum by generating an orbital flow. The orbital flow is converted into a spin flow in the metal layer (Pt and its alloys, Co and its alloys, Ni and its alloys, Fe and its alloys, Heusler alloy), and then magnetizes the magnetic moment of the adjacent ferromagnetic free layer Fe3GaTe2 to flip. The exchange bias effect between the antiferromagnetic FeMn and the ferromagnetic Fe3GaTe2 enables the free layer to realize the field-free assisted magnetization flipping without an external magnetic field. The Fe3GaTe2 / Co2Fe6B2 heterojunction utilizes the vertical anisotropy and two-dimensional characteristics of Fe3GaTe2 in combination with the high spin polarization rate mechanism of Co2Fe6B2, and can realize high magnetoresistance characteristics. At the same time, the [Co / Pt] n The vertical magnetic anisotropy (PMA) characteristics of the multilayer film ensure the stable magnetic state of the nanoscale storage unit. The barrier layer design effectively improves the writing precision and reliability, reduces the energy consumption, and enhances the thermal stability.

[0007] Further, the substrate is any one of SiO2, MgO and Al2O3, and the thickness of the substrate is 300 nm.

[0008] Further, the thickness of the metal layer is 1-5 nm, 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 alloy, and the thickness of the FeMn layer is 2-30 nm.

[0009] The FeMn layer is an antiferromagnetic layer, which provides an orbital flow and an exchange bias field, realizes efficient conversion of charge flow to spin flow, and reduces the magnetization flipping current density; at the same time, the exchange bias field can tilt the magnetic moment of the ferromagnetic layer, and then realize the field-free magnetization flipping; the metal layer is a spin-orbit coupling layer, which enhances the spin polarization current efficiency and provides a stray field, and then reduces the flipping current density and the field-free assisted magnetization flipping.

[0010] Specifically, FeMn can be coupled with Fe3GaTe2, and can reduce the auxiliary external magnetic field when Fe3GaTe2 is magnetized to flip, so as to achieve a high magnetization flip ratio. Therefore, using FeMn can reduce the size of the auxiliary external magnetic field, and realize the magnetization flip of Fe3GaTe2 without external magnetic field assistance.

[0011] Using the FeMn / metal layer combination can reduce the magnetization flip current density, thereby reducing power consumption.

[0012] The advantage of FeMn is not only in itself, but also in the functional stack composed of the upper and lower layers:

[0013] 1) Cooperate with the bottom electrode (such as Pt): form an orbital flow amplifier.

[0014] Synergistically produce orbital flow: Pt itself has a strong spin Hall effect, but the orbital Hall effect is weak. FeMn (especially the Mn-rich phase) is the opposite. By combining the two, Pt can be used as a seed layer to optimize the crystal growth orientation of FeMn, while FeMn can be used to generate high-purity orbital flow, achieving the effect of "1+1>2".

[0015] 2) Cooperate with the magnetic free layer (such as Fe3GaTe2): realize efficient writing and field-free stability.

[0016] High-efficiency orbital moment injection: The strong orbital flow generated by FeMn is efficiently converted into spin flow at the Fe3GaTe2 interface, driving the magnetization flip of Fe3GaTe2. Since the efficiency of orbital flow is much higher than that of traditional spin flow, the critical current density required to flip Fe3GaTe2 can be significantly reduced.

[0017] Induced exchange bias: Through interface coupling, FeMn can induce an exchange bias field in the adjacent Fe3GaTe2 layer. This built-in field acts like a lock, fixing a magnetization direction as the lowest energy state, thereby completely eliminating the dependence on external auxiliary magnetic field and achieving deterministic field-free flip. This is a core function that Pt and other simple heavy metals cannot provide.

[0018] 3) Cooperate with the top reference layer (such as [Co / Pt] n Multilayer film): build a complete MTJ (magnetic tunnel junction).

[0019] In addition, compared with other metals, such as CoCr, FeV, the OHE efficiency of Cr / V is significantly lower than that of Mn; in Co / Ni-containing alloys, the strong spin polarization of the ferromagnetic element (Co / Ni) suppresses the orbital Hall contribution of the light metal. Alloys containing Cr and V are prone to form oxides or diffuse at the interface, damaging the interface quality. The high-temperature ordering process of NiMn exacerbates interface diffusion and is uncontrollable. Therefore, FeMn has better effects.

[0020] Further, 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.

[0021] In order to improve the integration density of the device, a ferromagnetic material with out-of-plane magnetic crystalline anisotropy is selected. The two-dimensional magnetic layer Fe3GaTe2 has strong magnetic crystalline anisotropy, can realize high-sensitivity magnetoresistance effect of smaller device size, and has strong heat resistance and anti-interference. In addition, the two-dimensional characteristics of the Fe3GaTe2 material further reduce the energy and size required for the current to flip the magnetic moment of the device, so that the MTJ of the present application is suitable for non-volatile, low-power, high-density memory devices and orbital electronic applications.

[0022] The Co2Fe6B2 layer is a heavy metal / ferromagnetic buffer layer that regulates the spin polarization rate of the ferromagnetic layer.

[0023] In order to ensure the magnetic, electronic performance and overall stability of the structure, the same thickness of Co2Fe6B2 is selected on both sides of the barrier layer, which can ensure the symmetric magnetic layer, uniform electron transmission and higher spin polarization rate of the ferromagnetic layer, and improve the overall performance of the device.

[0024] Further, the material of the barrier layer is MgO, and the thickness is 1-3 nm.

[0025] The barrier layer is the core structure of the magnetic tunnel junction.

[0026] Further, the thickness of the second Co2Fe6B2 layer in the pinning layer is 0.8-1.5 nm, the thickness of the Ta layer is 0.8-1.3 nm, and 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.

[0027] The second Co2Fe6B2 layer as part of the pinning layer responds to changes in the external magnetic field;

[0028] The Ta layer acts as a diffusion barrier layer to inhibit interfacial atomic interdiffusion;

[0029] [Co / Pt] n The layer is a perpendicular magnetic anisotropy multilayer film, which constructs a high-density storage unit. By alternately stacking Co and Pt, the strong spin-orbit coupling of platinum is utilized, and the heavy element effect of platinum (especially in the atomic structure of the Pt layer) has a great influence on the magnetization direction. The magnetism of cobalt is strong, but due to the spin-orbit effect of platinum, the magnetization is easily arranged along the normal direction of the film (i.e. perpendicular to the film surface), thereby generating out-of-plane magnetic anisotropy. The spin-orbit coupling effect of Pt is crucial to the spin transport performance of the material.

[0030] Further, a protective layer is further included, the protective layer is located above the pinned layer, the material of the protective layer is Pt or Au, and the thickness is 1.6 nm. The protective layer is used to improve the environmental stability of the device.

[0031] The application further provides a preparation method of the orbital spin magnetic memory.

[0032] I. Depositing materials in each layer on the substrate in the order from bottom to top by a thin film preparation process, namely, the orbital Hall layer, the free layer, the barrier layer, the pinned layer (and the protective layer);

[0033] II. Preparing the orbital spin magnetic memory by micro-nano processing technology on the deposited film layer.

[0034] Further, the thin film preparation process includes magnetron sputtering, molecular beam epitaxy and mechanical peeling; and the micro-nano processing includes laser direct writing, electron beam lithography and reactive ion beam etching.

[0035] Compared with the prior art, the orbital spin magnetic memory and the preparation method thereof have the following advantages:

[0036] (1) The performance of the orbital spin magnetic memory is improved, and the write power consumption is reduced by 1-2 orders of magnitude compared with the conventional STT / SOT-MRAM (magnetic random access memory).

[0037] (2) The process of the orbital spin magnetic memory is simplified, the high-temperature growth step required by the conventional epitaxial growth is reduced by the integrated process of magnetron sputtering and mechanical peeling, energy consumption is saved, and the yield of the device is controlled by the micro-nano processing precision. DETAILED DESCRIPTION

[0038] The accompanying drawings, which form a part of the present application, are used to provide a further understanding of the present application, and the illustrative embodiments thereof and their descriptions are used to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0039] Figure 1 FIG. 1 is a structural schematic diagram of the orbital spin magnetic memory according to the embodiment of the present application;

[0040] Figure 2 FIG. 2 is the magnetization flipping performance of the orbital spin magnetic memory prepared in Example 1, (a) is an abnormal Hall resistance hysteresis loop, and (b) is a graph of the magnetoresistance (R xy ) and the current (I);

[0041] Figure 3 FIG. 3 is the magnetization flipping performance of the orbital spin magnetic memory prepared in Example 2, (a) is an abnormal Hall resistance hysteresis loop, and (b) is a graph of the magnetoresistance (R xy) and current (I) relationship diagram;

[0042] Figure 4 Structure of a conventional STT-MRAM;

[0043] Figure 5 Structure of a conventional SOT-MRAM;

[0044] Figure 6 Magnetization flipping performance of the orbital moment magnetic memory prepared for Comparative Example 3, (a) is an anomalous Hall resistance hysteresis loop; (b) is a magnetoresistance (R xy ) and current (I) relationship diagram;

[0045] Figure 7 Magnetization flipping performance of the orbital moment magnetic memory prepared for Comparative Example 4, (a) is an anomalous Hall resistance hysteresis loop; (b) is a magnetoresistance (R xy ) and current (I) relationship diagram;

[0046] Figure 8 Magnetization flipping performance of the orbital moment magnetic memory prepared for Comparative Example 5, (a) is an anomalous Hall resistance hysteresis loop; (b) is a magnetoresistance (R xy ) and current (I) relationship diagram;

[0047] Figure 9 Magnetization flipping performance of the orbital moment magnetic memory prepared for Comparative Example 6, (a) is an anomalous Hall resistance hysteresis loop; (b) is a magnetoresistance (R xy ) and current (I) relationship diagram;

[0048] Figure 10 Magnetization flipping performance of the orbital moment magnetic memory prepared for Comparative Example 7, (a) is an anomalous Hall resistance hysteresis loop; (b) is a magnetoresistance (R xy ) and current (I) relationship diagram.

[0049] Explanation of reference signs:

[0050] 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, pinned layer; 51, second Co2Fe6B2 layer; 52, Ta layer; 53, [Co / Pt] n layer; 6, protective layer. DETAILED DESCRIPTION

[0051] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0052] 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.

[0053] Example 1: Track-Modal Magnetic Storage

[0054] 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;

[0055] Substrate 1 is made of SiO2 and has a thickness of 300 nm.

[0056] 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.

[0057] 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.

[0058] Barrier layer 4 is an MgO layer with a thickness of 2 nm;

[0059] 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.

[0060] The protective layer is a Pt layer with a thickness of 1.6 nm.

[0061] The above-mentioned method for fabricating a orbital moment magnetic memory includes the following steps:

[0062] 1) First, FeMn and Pt layers are prepared sequentially by magnetron sputtering;

[0063] 2) The Fe3GaTe2 layer was prepared by mechanical exfoliation and transfer;

[0064] 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;

[0065] 4) Fabricating the orbital moment magnetic memory as shown in Figure 1 FIG. 1 using micro-nano processing technology such as laser direct writing, electron beam lithography and reactive ion beam etching.

[0066] Figure 2 The performance of the orbital moment magnetic memory prepared in this embodiment is shown, wherein (a) the graph curve is a "closed loop", indicating that the magnetoresistance of the device changes with the magnetic field and has a hysteresis effect, embodying the hysteresis of the internal magnetic moment of the material, indicating that the orbital moment memory can be used for magnetization reversal test. (b) The graph reflects the magnetoresistance behavior under the synergistic action of current and magnetic field. When there is no auxiliary magnetic field (0 Oe): the amplitude of the magnetoresistance changes with the current is small (the curve is "flat"), the magnetoresistance effect changes little, indicating that the effect of the current alone on the magnetoresistance is small; after applying a magnetic field: the curve is a "loop", and the stronger the magnetic field (such as 600 Oe), the larger the loop amplitude, indicating that the magnetic field enhances the response of the magnetoresistance to the current, embodying the characteristics of "magnetic field-current synergistic reversal of magnetic moment".

[0067] Embodiment 2

[0068] As shown in Figure 1 , an orbital moment magnetic memory, comprising, from bottom to top, a substrate 1, an orbital Hall layer 2, a free layer 3, a barrier layer 4, a pinned layer 5 and a protective layer 6;

[0069] The substrate 1 is SiO2, and the thickness of the substrate 1 is 300 nm;

[0070] The orbital Hall layer 2 comprises a metal layer 22 and a FeMn layer 21 arranged in a top-to-bottom manner, the thickness of the FeMn layer 21 is 5 nm, and the metal layer 22 is a Ni layer with a thickness of 1 nm;

[0071] The free layer 3 comprises a first Co2Fe6B2 layer 32 and a Fe3GaTe2 layer 31 arranged in a top-to-bottom manner, the thickness of the Fe3GaTe2 layer 31 is 8 nm, and the thickness of the first Co2Fe6B2 layer 32 is 1.3 nm;

[0072] The barrier layer 4 is a MgO layer with a thickness of 2 nm;

[0073] The pinned layer 5 comprises, from top to bottom, a [Co / Pt] n layer 53, a Ta layer 52 and a second Co2Fe6B2 layer 51, the thickness of the second Co2Fe6B2 layer 51 is 1.3 nm, the thickness of the Ta layer 52 is 0.8 nm, and the thickness of the [Co / Pt] n layer 53 is 4.4 nm, and n=4;

[0074] The protective layer is a Pt layer with a thickness of 1.6 nm.

[0075] The preparation method is the same as that of embodiment 1.

[0076] The track moment magnetic storage device can be roughly divided into two parts, one is the magnetization flip of the free layer, and the other is the fixed layer. If the free layer magnetization flip can be combined with the fixed layer to form an OT-MRAM, a low-power track moment magnetic storage device can be realized. Therefore, the most important part of the track moment magnetic storage device is the FeMn / metal layer / Fe3GaTe2 / Co2Fe6B2 structure.

[0077] Figure 3 The performance of the track moment magnetic storage device prepared in this embodiment is shown. The curve in (a) is a “closed loop”, indicating that the magnetoresistance of the device changes with the magnetic field and has a hysteresis effect, reflecting the hysteresis of the internal magnetic moment of the material, indicating that the track moment storage device can be used for magnetization flip test. The graph in (b) reflects the magnetoresistance behavior under the synergistic action of current and magnetic field. When there is no auxiliary magnetic field (0 Oe): the amplitude of the magnetoresistance changes with the current is small (the curve is “flat”), the magnetoresistance effect changes little, indicating that the effect of current alone on the magnetoresistance is small; after applying a magnetic field: the curve is a “loop”, and the stronger the magnetic field (such as 600 Oe), the larger the loop amplitude, indicating that the magnetic field enhances the response of the magnetoresistance to the current, reflecting the characteristics of “magnetic field-current synergistic flip magnetic moment”.

[0078] From Figures 2-3 , it can be seen that the magnetization flip of the two storage devices is realized, and the magnetization flip polarity is opposite when the opposite magnetic field is applied, which excludes the thermal effect. The resistivity of FeMn / Pt and Fe3GaTe2 / Co2Fe6B2 is measured by I-V method (calculation formula p = RS / L ), and then the magnetization flip current density is calculated by proportional shunting to be about 9×10 6 A / cm 2 .

[0079] The magnetization flip current density is about 9×10 6 A / cm 2 , which is one to two orders of magnitude lower than the magnetization flip current density (write power consumption) of the three-dimensional ferromagnetic free layer.

[0080] Comparative Example 1: Traditional STT-MRAM

[0081] The structure is shown in Figure 4 , and STT is observed in the two-end geometry, in which a perpendicular current is injected through an MTJ (magnetic tunnel junction). The current tunneling through the barrier is spin-polarized, and the free layer can perform magnetization flip when the current is large enough. The relative magnetization direction of the free layer and the fixed layer determines the resistance of the device, which is monitored by tunnel magnetoresistance (TMR).

[0082] Comparative Example 2: Traditional SOT-MRAM

[0083] Its structure is shown in Figure 5 SOT-MRAM is based on a three-terminal device, where an additional conduction path is added near the free layer. Due to the spin Hall effect and / or Rashba-Edelstein effect, the charge current flowing through this path causes spin-polarized current injection into the free layer. In this device, SOT can switch the magnetization direction of the free layer without passing current 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.

[0084] The magnetization reversal of STT-MRAM, whose current passes through the barrier layer to change the magnetization direction of the free layer, will fail after too many times of magnetization reversal. The magnetization reversal of SOT-MRAM does not need to pass through the barrier layer, ensuring the stability and reliability of the device. However, the current density of SOT-MRAM is higher than that of Example 1, as shown in Figure 2 The magnetization reversal current is 8.5 mA (~ 9 x 10 6 A / cm 2 , which is 1-2 orders of magnitude lower than that of traditional three-dimensional SOT-MRAM devices.

[0085] Comparative Example 3 FeMn thickness is too thin

[0086] Compared with the structure of Example 1, the thickness of FeMn is 1 nm.

[0087] As can be seen from Figure 6 (a) and Figure 6 (b), the R xy The magnetoresistance change at 0 field and the hysteresis loop under the assistance of an external magnetic field do not change much, with a difference of about 1.2 Ω. Based on the same magnetization reversal ratio, the power consumption is higher.

[0088] Comparative Example 4 FeMn thickness is too thick

[0089] Compared with the structure of Example 1, the thickness of FeMn is 35 nm.

[0090] Figure 7 (a) The hysteresis loop fluctuates greatly and is unstable (such as curve jump, noisy), and the magnetoresistance changes abruptly with the magnetic field, reflecting that the magnetic moment reversal is disturbed and the magnetic stability is poor.

[0091] Figure 7 (b) The curve fluctuates greatly and is irregular (such as "many burrs" in the 600 Oe curve), indicating that the repeatability of current-controlled magnetoresistance is poor, the device consistency is low, and the current-controlled magnetoresistance is "chaotic and inefficient" (curve fluctuation), which may require more current to "cover" the fluctuations, resulting in higher power consumption.

[0092] Comparative Example 5 Replace FeMn

[0093] Compared with the structure of Example 1, FeMn is replaced by Zr.

[0094] Figure 8 (a) The hysteresis loop is also fluctuant and discontinuous, and the magnetic stability is poor.

[0095] Figure 8 (b) The curve fluctuates greatly and is irregular (e.g. the 600Oe curve has many "spikes"), which reflects that the efficiency of current-regulated magnetoresistance is low, the repeatability is poor, the device consistency is weak, the current-regulated magnetoresistance is "inefficient and chaotic", and the power consumption is higher.

[0096] Comparative Example 6 Fe3GaTe2 is too thick

[0097] Compared with the structure of Example 1, the thickness of Fe3GaTe2 is 25nm.

[0098] Figure 9 (a) It is shown that the magnetic easy axis of Fe3GaTe2 with too large thickness is deviated from the out-of-plane to the in-plane, resulting in too small coercivity and poor stability.

[0099] Figure 9 (b) The curve has obvious fluctuation under some magnetic fields (e.g. -600Oe, -500Oe, etc.), which shows that the current-regulated magnetoresistance process is more disturbed, the performance repeatability and stability are poor, and the power consumption is relatively higher.

[0100] Comparative Example 7 Replace FeMn with pure Pt

[0101] Compared with the structure of Example 1, FeMn is replaced by pure Pt.

[0102] From Figure 10 It can be seen that (a) the hysteresis loop is good, but the coercivity is too large, and the required magnetization reversal current is also larger. (b) The curve shape is special (e.g. the -500Oe curve is a "rectangular hysteresis loop"), the difference between the magnetoresistance-current responses under different magnetic fields is large, which reflects that the mode of current-regulated magnetoresistance changes dramatically with the magnetic field, there is only a stable rectangular hysteresis loop at a specific magnetic field (e.g. -500Oe), and the power consumption is high and the versatility is poor.

[0103] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A track-moment magnetic storage device, characterized in that: The orbital magnetic memory 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 comprises a metal layer and an FeMn layer disposed vertically. The free layer comprises a first Co2Fe6B2 layer and an Fe3GaTe2 layer disposed vertically. The fixing layer comprises [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.

2. The orbital moment magnetic storage device according to claim 1, characterized in that: The substrate is any one of SiO2, MgO, and Al2O3.

3. The orbital moment magnetic storage device according to claim 1, characterized in that: 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; the thickness of the FeMn layer is 2-30 nm.

4. The orbital moment magnetic storage device according to claim 1, characterized in that: 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.

5. The orbital moment magnetic storage device according to claim 1, characterized in that: The barrier layer is made of MgO and has a thickness of 1-3 nm.

6. The orbital moment magnetic storage device according to claim 1, characterized in that: 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 is... n The Co layer has a thickness of 0.4 nm, and the Pt layer has a thickness of 0.8 nm.

7. The orbital moment magnetic storage device according to claim 1, characterized in that: It also includes a protective layer, which is located above the fixing layer. The material of the protective layer is Pt or Au, and the thickness is 1.6 nm.

8. A method for preparing a track-moment magnetic storage device as described in any one of claims 1-7, characterized in that: The method includes 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, and the tethering layer; II. The deposited film is used to fabricate orbital moment micro magnetic memory using micro-nano fabrication technology.

9. The method for preparing the orbital moment magnetic storage device according to claim 8, characterized in that: Thin film fabrication processes include magnetron sputtering, molecular beam epitaxy, and mechanical exfoliation; micro-nano fabrication technologies include laser direct writing, electron beam lithography, and reactive ion beam etching.

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