Magnetic storage element and manufacturing method thereof

Abstract

The invention provides a magnetic storage element and a manufacturing method thereof, relates to the technical field of semiconductors, and is used for solving the problem of low overturning efficiency of a free layer in the prior art. The magnetic storage element comprises a substrate, a spacing layer, a spin orbit moment layer and a magnetic tunnel junction which are sequentially stacked from bottom to top, and a first ferromagnetic structure and a second ferromagnetic structure which are independently arranged on two side walls of the spacing layer, the first ferromagnetic layer in the first ferromagnetic structure and the second ferromagnetic layer in the second ferromagnetic structure are opposite in magnetic moment direction, so that stray fields in opposite directions can be generated; the top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin orbit moment layer and are electrically connected with the spin orbit moment layer to form a write-in path, and when write-in current flows through the first ferromagnetic structure or the second ferromagnetic structure, a stray field generated by the ferromagnetic structure through which the write-in current flows is weakened; a stray field generated by the ferromagnetic structure through which the write-in current does not flow assists the free layer in overturning, and the overturning efficiency of the free layer can be improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and particularly to a magnetic storage element and a manufacturing method thereof. Background Art

[0002] With the miniaturization of semiconductor technology nodes, current conventional semiconductor storage technologies are restricted, and more and more new types of memories have emerged. Among them, Spin Orbit Torque-Magnetic Random Access Memory (SOT-MRAM) has gradually been noticed due to its many advantages such as higher durability and non-volatility. The main structure of SOT-MRAM is a Magnetic Tunnel Junction (MTJ), including: a free layer, a barrier layer, and a reference layer. A spin orbit torque layer is provided below the free layer. When a write current is applied to the spin orbit torque layer, a spin orbit coupling effect will be generated, thereby generating a spin torque to drive the free layer to undergo a directional flip. Therefore, the flip efficiency of the free layer is particularly important. A low flip efficiency will lead to an increase in device power consumption.

[0003] The prior art improves the flip efficiency of the free layer by optimizing the spin orbit torque layer material and other auxiliary flipping means. For example, a ferromagnetic layer is added below the spin orbit torque layer, and the ferromagnetic layer changes the polarization direction of spin-polarized electrons to enhance the flip efficiency of the free layer. However, this method has a very limited improvement in the flip efficiency. In addition, in related technologies, a ferromagnetic layer is also filled in the bottom via to provide a stray field to assist the free layer flip. However, it requires that the magnetic moment directions of the two vias to be written are opposite, and it is very difficult to achieve two opposite magnetic moments simultaneously using a conventional annealing process. Summary of the Invention

[0004] To solve the above problems, embodiments of this application provide a magnetic storage element and a manufacturing method thereof to improve the flip efficiency of the free layer of the magnetic storage element.

[0005] According to some embodiments, embodiments of this application provide a magnetic storage element, which at least includes a substrate, a spacer layer, a spin orbit torque layer, and a magnetic tunnel junction stacked in sequence from bottom to top, and a first ferromagnetic structure and a second ferromagnetic structure independently disposed on two sidewalls of the spacer layer; the top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin orbit torque layer and are electrically connected to the spin orbit torque layer; the first ferromagnetic structure includes a first ferromagnetic layer, the second ferromagnetic structure includes a second ferromagnetic layer, and the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite.

[0006] In some possible implementation manners, both the first ferromagnetic structure and the second ferromagnetic structure are composite film layer structures. The first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer. The order of the film layers in the first ferromagnetic structure is the same as that of the film layers in the second ferromagnetic structure.

[0007] In some possible implementation manners, the projected area of the spacer layer on the substrate is smaller than the projected area of the spin-orbit torque layer on the substrate, so that the first ferromagnetic structure and the second ferromagnetic structure are in partial contact with the bottom surface of the spin-orbit torque layer.

[0008] In some possible implementation manners, the top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are flush with the bottom surface of the spin-orbit torque layer.

[0009] In some possible implementation manners, the write current sequentially flows through the first ferromagnetic structure, the spin-orbit torque layer, and the magnetic tunnel structure to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure is weakened, and the stray field generated by the second ferromagnetic structure assists the magnetic storage element to flip to a first resistance state. The write current sequentially flows through the second ferromagnetic structure, the spin-orbit torque layer, and the magnetic tunnel structure to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure is weakened, and the stray field generated by the first ferromagnetic structure assists the magnetic storage element to flip to a second resistance state.

[0010] In some possible implementation manners, a first conductive part is correspondingly arranged below the spin-orbit torque layer. The write current sequentially flows through the first ferromagnetic structure, the spin-orbit torque layer, and the first conductive part to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure is weakened, and the stray field generated by the second ferromagnetic structure assists the magnetic storage element to flip to a first resistance state. The write current sequentially flows through the second ferromagnetic structure, the spin-orbit torque layer, and the first conductive part to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure is weakened, and the stray field generated by the first ferromagnetic structure assists the magnetic storage element to flip to a second resistance state.

[0011] The magnetic storage element provided by the embodiment of the present application has at least the following advantages: In the magnetic storage element in the embodiments of the present application, by providing a first ferromagnetic structure and a second ferromagnetic structure on both sides of the spacer layer, and the magnetic moment directions of the first ferromagnetic layer in the first ferromagnetic structure and the second ferromagnetic layer in the second ferromagnetic structure are opposite, stray fields in opposite directions can be generated; the first ferromagnetic structure and the second ferromagnetic structure are electrically connected to the spin-orbit torque layer to respectively form a write path. When a write current flows through the first ferromagnetic structure or the second ferromagnetic structure respectively, the stray field generated by the ferromagnetic structure through which the write current flows is weakened, and the stray field generated by the ferromagnetic structure through which the write current does not flow assists the free layer to flip, improving the flipping efficiency of the free layer and reducing the power consumption of the magnetic storage element; moreover, the first ferromagnetic structure and the second ferromagnetic structure form a bottom electrode interconnection with the spin-orbit torque layer, replacing the original all-spin-orbit torque layer bottom electrode structure, thereby reducing the bottom electrode resistance and further reducing the power consumption; in addition, the first ferromagnetic structure and the second ferromagnetic structure can also be used as an etching stop layer for the spin-orbit torque layer, solving the problem of difficult endpoint stopping in etching the spin-orbit torque layer, reducing the process difficulty, and also enabling the spin-orbit torque layer and the magnetic tunnel junction to be obtained by one-step etching, simplifying the process steps.

[0012] According to some embodiments, the present application further provides a method for manufacturing a magnetic storage element, including the following steps: forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure on a substrate, and the first ferromagnetic structure and the second ferromagnetic structure are independently formed on both sidewalls of the spacer layer; sequentially forming a spin-orbit torque layer and a magnetic tunnel junction above the spacer layer; the top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin-orbit torque layer and are electrically connected to the spin-orbit torque layer; wherein, the first ferromagnetic structure includes a first ferromagnetic layer, the second ferromagnetic structure includes a second ferromagnetic layer, and the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite.

[0013] In some possible implementation manners, both the first ferromagnetic structure and the second ferromagnetic structure are composite film layer structures, the first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer; the order of the film layers in the first ferromagnetic structure is the same as the order of the film layers in the second ferromagnetic structure.

[0014] In some possible implementation manners, forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure on a substrate, and the first ferromagnetic structure and the second ferromagnetic structure are independently formed on both sidewalls of the spacer layer specifically includes: sequentially forming a ferromagnetic layer, an antiferromagnetic layer, and a first dielectric layer on the substrate from bottom to top; removing a part of the first dielectric layer, forming a groove on the first dielectric layer, and the remaining first dielectric layers on both sides of the groove have different heights and are both higher than the bottom surface of the groove; using the remaining first dielectric layer as a mask to etch the antiferromagnetic layer and the ferromagnetic layer to form independent first and second ferromagnetic structures, wherein the remaining first and second antiferromagnetic layers have different thicknesses; filling a second dielectric layer between the first ferromagnetic structure and the second ferromagnetic structure to form a spacer layer.

[0015] In some possible implementations, the heights of the remaining first dielectric layers on both sides of the groove are different and both are higher than the bottom surface of the groove. Specifically, the height difference between the top surface of the remaining first dielectric layer on one side of the groove and the bottom surface of the groove is not less than the sum of the thicknesses of the antiferromagnetic layer and the ferromagnetic layer, and the height difference between the top surface of the remaining first dielectric layer on the other side of the groove and the bottom surface of the groove is not less than the thickness of the ferromagnetic layer and not higher than the sum of the thicknesses of the antiferromagnetic layer and the ferromagnetic layer.

[0016] The manufacturing method of the magnetic storage element in the embodiment of the present application has at least the following advantages: In the manufacturing method of the magnetic storage element in the embodiment of the present application, by forming a first ferromagnetic structure and a second ferromagnetic structure on both sides of the spacer layer, and the magnetic moment directions of the first ferromagnetic layer in the first ferromagnetic structure and the second ferromagnetic layer in the second ferromagnetic structure are opposite, stray fields in opposite directions can be generated; the first ferromagnetic structure and the second ferromagnetic structure are electrically connected to the spin-orbit torque layer to form write paths respectively. When write currents flow through the first ferromagnetic structure or the second ferromagnetic structure respectively, the stray field generated by the ferromagnetic structure through which the write current flows weakens, and the stray field generated by the ferromagnetic structure through which the write current does not flow assists the free layer to flip, improving the free layer flipping efficiency and reducing the power consumption of the magnetic storage element; the first ferromagnetic structure and the second ferromagnetic structure are electrically connected to the spin-orbit torque layer to form a bottom electrode interconnection, replacing the original all-spin-orbit torque layer bottom electrode structure, thereby reducing the bottom electrode resistance and further reducing the power consumption; in addition, the first ferromagnetic structure and the second ferromagnetic structure can also be used as an etching stop layer for the spin-orbit torque layer, which can solve the problem of difficult end-stop etching of the spin-orbit torque layer, reduce the process difficulty, and can also achieve etching the spin-orbit torque layer and the magnetic tunnel junction in one step, simplifying the process steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional schematic diagram of the first magnetic storage element in an embodiment of the present application.

[0018] Figure 2 It is a cross-sectional schematic diagram of the first magnetic storage element in an embodiment of the present application in the direction of the write current.

[0019] Figure 3 It is a cross-sectional schematic diagram of the third magnetic storage element in an embodiment of the present application.

[0020] Figure 4 It is a cross-sectional schematic diagram of the third magnetic storage element in an embodiment of the present application in the direction of the write current.

[0021] Figure 5 It is a flowchart of the manufacturing method of the magnetic storage element in an embodiment of the present application.

[0022] Figure 6Schematic cross-sectional view of a magnetic storage element after forming a first ferromagnetic structure and a second ferromagnetic structure in a first method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0023] Figure 7 Schematic cross-sectional view of a magnetic storage element after forming a groove on a first dielectric layer in a fourth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0024] Figure 8 Schematic cross-sectional view of a magnetic storage element finally formed in a fourth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0025] Figure 9 Schematic cross-sectional view of a magnetic storage element after forming a groove on a first dielectric layer in a fifth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0026] Figure 10 Schematic cross-sectional view of a magnetic storage element after depositing a ferromagnetic layer above a first antiferromagnetic layer and a second antiferromagnetic layer in a fifth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0027] Figure 11 Schematic cross-sectional view of a magnetic storage element after forming a first ferromagnetic structure and a second ferromagnetic structure in a fifth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0028] Figure 12 Schematic cross-sectional view of a magnetic storage element after forming a first antiferromagnetic layer and a second antiferromagnetic layer in a sixth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0029] Figure 13 Schematic cross-sectional view of a magnetic storage element after depositing a ferromagnetic layer above a first antiferromagnetic layer and a second antiferromagnetic layer in a sixth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0030] Figure 14 Schematic cross-sectional view of a magnetic storage element after forming a first ferromagnetic structure and a second ferromagnetic structure in a sixth method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0031] Figure 15 Schematic cross-sectional view of a magnetic storage element after etching a first antiferromagnetic material in a seventh method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0032] Figure 16 Schematic cross-sectional view of a magnetic storage element after etching a second antiferromagnetic material in the seventh method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0033] Figure 17 Schematic cross-sectional view of a magnetic storage element after forming a first ferromagnetic structure and a second ferromagnetic structure in the seventh method for forming a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in an embodiment of the present application.

[0034] Figure 18 Schematic cross-sectional view of a magnetic storage element after depositing a spin-orbit torque film layer, a magnetic tunnel junction film layer, and a hard mask layer in another method for forming a spin-orbit torque layer and a magnetic tunnel junction in an embodiment of the present application.

[0035] Figure 19 Schematic cross-sectional view of a magnetic storage element after shrinking a hard mask layer in another method for forming a spin-orbit torque layer and a magnetic tunnel junction in an embodiment of the present application.

[0036] Figure 20 Schematic cross-sectional view of a finally formed magnetic storage element in another method for forming a spin-orbit torque layer and a magnetic tunnel junction in an embodiment of the present application.

[0037] Explanation of reference numerals: 10 - Substrate; 20 - Spacer layer; 30 - Spin-orbit torque layer; 40 - Magnetic tunnel junction; 50 - First ferromagnetic structure; 51 - First ferromagnetic layer; 52 - First antiferromagnetic layer; 60 - Second ferromagnetic structure; 61 - Second ferromagnetic layer; 62 - Second antiferromagnetic layer; 70 - Top electrode; 80 - Bottom via; 90 - Dielectric layer; 100 - First conductive via; 110 - Second conductive via; 120 - First dielectric layer; 130 - Ferromagnetic layer; 140 - Antiferromagnetic layer; 141 - First antiferromagnetic material; 142 - Second antiferromagnetic material; 150 - Top via; 160 - Spin-orbit torque film layer; 170 - Magnetic tunnel junction film layer; 180 - Hard mask layer; 190 - Second dielectric layer. Detailed implementation manners

[0038] In SOT-MRAM, the device power consumption is usually reduced by improving the switching efficiency of the free layer. Existing technologies improve the switching efficiency of the free layer by optimizing the spin-orbit torque layer material and other auxiliary switching means. For example, a ferromagnetic layer is added under the spin-orbit torque layer, and the polarization direction of the spin-polarized electrons is changed by the ferromagnetic layer to enhance the switching efficiency of the free layer. However, this method has a very limited improvement in the switching efficiency. In addition, in related technologies, a ferromagnetic layer is filled in the bottom via to provide a stray field to assist the free layer switching. However, it requires that the magnetic moment directions of the two vias to be written are opposite, and it is very difficult to achieve two opposite magnetic moments simultaneously using a conventional annealing process, and the process implementation is very difficult.

[0039] In the magnetic storage element according to the embodiment of the present application, by setting a first ferromagnetic structure and a second ferromagnetic structure on both sides of the spacer layer, and the magnetic moment directions of the first ferromagnetic layer in the first ferromagnetic structure and the second ferromagnetic layer in the second ferromagnetic structure are opposite, stray fields in opposite directions can be generated; the first ferromagnetic structure and the second ferromagnetic structure are electrically connected to the spin-orbit torque layer to form write paths respectively. When write currents flow through the first ferromagnetic structure or the second ferromagnetic structure respectively, the stray field generated by the ferromagnetic structure through which the write current flows weakens, and the stray field generated by the ferromagnetic structure through which the write current does not flow assists the free layer to switch, improving the switching efficiency of the free layer and reducing the power consumption of the magnetic storage element; the first ferromagnetic structure and the second ferromagnetic structure form a bottom electrode interconnection with the spin-orbit torque layer, replacing the original all-spin-orbit torque layer bottom electrode structure, thereby reducing the bottom electrode resistance and further reducing the power consumption; in addition, the first ferromagnetic structure and the second ferromagnetic structure can also be used as an etching stop layer for the spin-orbit torque layer, solving the problem of difficult etching endpoint stopping of the spin-orbit torque layer and reducing the process difficulty; and it can also achieve etching the spin-orbit torque layer and the magnetic tunnel junction in one step, simplifying the process steps.

[0040] In order to make the above objects, features, and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments of the present application are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present application.

[0041] An embodiment of the present application provides a magnetic storage element, which at least includes a substrate, a spacer layer, a spin-orbit torque layer, and a magnetic tunnel junction stacked in sequence from bottom to top, and a first ferromagnetic structure and a second ferromagnetic structure independently disposed on two sidewalls of the spacer layer; the top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin-orbit torque layer and are electrically connected to the spin-orbit torque layer; the first ferromagnetic structure includes a first ferromagnetic layer, the second ferromagnetic structure includes a second ferromagnetic layer, and the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite.

[0042] Reference Figure 1 , which is a schematic diagram of the first magnetic storage element provided by the embodiment of the present application, and at least includes: a substrate 10, a spacer layer 20, a spin-orbit torque layer 30, and a magnetic tunnel junction 40, and a first ferromagnetic structure 50 and a second ferromagnetic structure 60 independently disposed on two sidewalls of the spacer layer 20; wherein, the top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are not higher than the top surface of the spin-orbit torque layer 30 and are electrically connected to the spin-orbit torque layer 30; the first ferromagnetic structure 50 includes a first ferromagnetic layer (not shown in the figure), the second ferromagnetic structure 60 includes a second ferromagnetic layer (not shown in the figure), and the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite.

[0043] In the magnetic storage element provided by this embodiment, the material of the substrate 10 can be a semiconductor material, such as silicon, silicon carbide, gallium nitride, aluminum nitride, etc., or an insulating material, such as germanium; it can also be a logic substrate containing a logic circuit inside.

[0044] The spacer layer 20 is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc.

[0045] The spin-orbit torque layer 30 is a material that can generate a spin-orbit torque effect, including metals and their alloys such as platinum, palladium, hafnium, gold, tantalum, tungsten, iridium, etc.; or topological insulators, including bismuth selenide (Bi x Se 1-x ), bismuth antimonide (Bi x Sb 1-x ), bismuth telluride-based materials (Bi,Sb) 2 Te 3 etc., where 0 < x < 1; it can also be a two-dimensional material, such as molybdenum disulfide (MoS 2 ), tungsten ditelluride (WTe 2 ), etc.; the spin-orbit torque layer 30 can be a single-layer film or a multi-layer composite film, including a combination of two or more of the above materials.

[0046] The magnetic tunnel junction 40 is a core component of the magnetic storage element for data storage. Its shape is oval, and it can also be circular, triangular, rhombic, etc., without any limitation here. Its structure is a multi-layer composite structure (not shown in the figure), including, from bottom to top: a free layer, a barrier layer, and a reference layer. The materials of the free layer and the reference layer can be ferromagnetic materials, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc. and their alloys, or can be ferrimagnetic materials; the free layer and the reference layer can be single-layer or multi-layer composite film layers; the material of the barrier layer is an insulating material, such as magnesium oxide, aluminum oxide, silicon oxide, etc. In addition, a pinning layer can be provided in the magnetic tunnel junction 40, located on the side of the reference layer away from the barrier layer to fix the magnetization direction of the reference layer.

[0047] The first ferromagnetic structure 50 and the second ferromagnetic structure 60 are independently arranged on the two side walls of the spacer layer 20 and do not contact each other. The first ferromagnetic structure 50 and the second ferromagnetic structure 60 can both be single-film layer structures, respectively including a first ferromagnetic layer (not shown in the figure) and a second ferromagnetic layer (not shown in the figure). The first ferromagnetic layer and the second ferromagnetic layer are both ferromagnetic materials, such as permalloy, cobalt-iron alloy, etc. Their materials can be the same or different, and their thicknesses can be the same or different. Among them, the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite to generate stray fields in opposite directions to assist the free layer to flip, improve the flipping efficiency of the free layer, and reduce the power consumption of the device. Dielectric layers 90 can also be respectively provided above the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to protect the side walls of the first ferromagnetic structure 50 and the second ferromagnetic structure 60.

[0048] To make the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer opposite, annealing while applying a magnetic field can be adopted. When the materials and film thicknesses of the first ferromagnetic layer and the second ferromagnetic layer are the same, the coercive fields for flipping their magnetic moments are the same. By annealing the first ferromagnetic layer and the second ferromagnetic layer respectively while applying magnetic fields in opposite directions, the magnetic moments of the first ferromagnetic layer and the second ferromagnetic layer are opposite. When the materials of the first ferromagnetic layer and the second ferromagnetic layer are different or the materials are the same but the thicknesses are different, their coercive fields are different. For example, if the coercive field of the material forming the first ferromagnetic layer is greater than that of the material forming the second ferromagnetic layer, or if the materials of the first ferromagnetic layer and the second ferromagnetic layer are the same but the thickness of the first ferromagnetic layer is greater than that of the second ferromagnetic layer, the coercive field of the first ferromagnetic layer will be greater than that of the second ferromagnetic layer. A larger magnetic field needs to be applied to the first ferromagnetic layer to fix its magnetic moment. Therefore, the first ferromagnetic layer and the second ferromagnetic layer need to be annealed twice. During the first annealing, a magnetic field is applied in a certain direction, and the magnitude of this magnetic field is greater than the coercive field of the first ferromagnetic layer. The magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are both fixed in the same direction. At this time, the second annealing is carried out while applying a magnetic field in the direction opposite to that during the first annealing. The magnitude of this magnetic field is greater than the coercive field of the second ferromagnetic layer and less than the coercive field of the first ferromagnetic layer. The magnetic moment direction of the first ferromagnetic layer is not affected, and the magnetic moment of the second ferromagnetic layer is fixed in the direction opposite to that of the first ferromagnetic layer.

[0049] The top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are not higher than the top surface of the spin-orbit torque layer 30 to avoid short-circuiting of the magnetic tunnel junction 40. Moreover, the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are respectively electrically connected to the spin-orbit torque layer 30 to form an interconnected bottom electrode. The electrical connection method can be direct contact electrical connection or electrical connection through a conductive component. The formed interconnected bottom electrode can solve the problem of increased resistance caused by etching damage of the spin-orbit torque layer 30, thereby reducing the bottom electrode resistance and further reducing the power consumption of the magnetic storage element. Also, when etching the spin-orbit torque layer 30, the first ferromagnetic structure 50 and the second ferromagnetic structure 60 can be used as an etching stop layer to solve the problem of difficult stopping at the end point of etching the spin-orbit torque layer 30 and reduce the process difficulty.

[0050] Furthermore, the projected area of the spacer layer 20 on the substrate 10 can also be smaller than the projected area of the spin-orbit torque layer 30 on the substrate 10, so that the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are in partial contact with the bottom surface of the spin-orbit torque layer 30 to directly form an interconnected bottom electrode, further reducing the bottom electrode resistance. Even further, the top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are flush with the bottom surface of the spin-orbit torque layer 30, which is convenient for directly forming the spin-orbit torque layer 30 and the magnetic tunnel junction 40 on the flat top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60, simplifying the manufacturing process.

[0051] In addition, the projected area of the spin-orbit torque layer 30 on the substrate 10 can be equal to the projected area of the magnetic tunnel junction 40 on the substrate 10. Based on the etching stop layer formed by the first ferromagnetic structure 50 and the second ferromagnetic structure 60, only one etching step can be used to simultaneously obtain the spin-orbit torque layer 30 and the magnetic tunnel junction 40, saving one etching process and simplifying the manufacturing steps; there is no redundant spin-orbit torque layer 30 on both sides of the magnetic tunnel junction 40, which can further reduce the bottom electrode resistance and the power consumption of the magnetic storage element.

[0052] In the magnetic storage element according to the embodiment of the present application, the write current sequentially flows through the first ferromagnetic structure 50, the spin-orbit torque layer 30 and the magnetic tunnel junction 40 to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure 50 weakens, and the stray field generated by the second ferromagnetic structure 60 assists the magnetic storage element to flip to the first resistance state; the write current sequentially flows through the second ferromagnetic structure 60, the spin-orbit torque layer 30 and the magnetic tunnel junction 40 to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure 60 weakens, and the stray field generated by the first ferromagnetic structure 50 assists the magnetic storage element to flip to the second resistance state.

[0053] Specifically, referring to Figure 2 , which is a schematic diagram of the write current direction of the magnetic storage element according to the embodiment of the present application, the first write current I w1 flows in from the first ferromagnetic structure 50, passes through the spin-orbit torque layer 30 and the magnetic tunnel junction 40, and flows out from the top electrode 70 to form a first write path; the second write current I w2 flows in from the second ferromagnetic structure 60, passes through the spin-orbit torque layer 30 and the magnetic tunnel junction 40, and flows out from the top electrode 70 to form a second write path. In the initial state of the magnetic storage element, the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite, and at this time, the stray field received by the free layer is in a balanced or approximately balanced state; when the write current I w1 flows through the first ferromagnetic structure 50 through the first write path, the first ferromagnetic structure 50 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the second ferromagnetic structure 60 dominates and assists the free layer to flip to the first resistance state; similarly, when the write current I w2 flows through the second ferromagnetic structure 60 through the second write path, the second ferromagnetic structure 60 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the first ferromagnetic structure 50 dominates and assists the free layer to flip to the second resistance state. By making the write current flow through the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to generate stray fields with opposite directions to assist the free layer to flip, the flipping efficiency of the free layer can be improved and the power consumption of the magnetic storage element can be reduced.

[0054] Among them, the first resistance state and the second resistance state are resistance states of two opposite states. For example, the first resistance state is a resistance state where the magnetic moments of the free layer and the reference layer are anti-parallel, and the second resistance state is a resistance state where the magnetic moments of the free layer and the reference layer are parallel; it can also be that the first resistance state is a resistance state where the magnetic moments of the free layer and the reference layer are parallel, and the second resistance state is a resistance state where the magnetic moments of the free layer and the reference layer are anti-parallel, which is not limited here.

[0055] Continue to refer to Figure 2 , in the magnetic storage element of the embodiment of the present application, bottom vias 80 can also be respectively provided corresponding to the first ferromagnetic structure 50 and the second ferromagnetic structure 60. The bottom vias 80 can be provided in the substrate to achieve electrical connection with an external circuit for data writing and reading; in addition, the bottom vias 80 can also not be provided, and a conductive terminal (not shown in the figure) can be provided on both sides of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to input a write current, without the need to adopt complex process steps such as digging holes, which can simplify the manufacturing process. Here, the input component of the write current is not limited.

[0056] The embodiment of the present application also provides a second magnetic storage element, which is mainly different from the first magnetic storage element in that: the first ferromagnetic structure and the second ferromagnetic structure are composite film layer structures, the first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer; the order of each film layer in the first ferromagnetic structure is the same as the order of each film layer in the second ferromagnetic structure.

[0057] In the magnetic storage element of this embodiment, a first antiferromagnetic layer and a second antiferromagnetic layer are respectively provided in the first ferromagnetic structure and the second ferromagnetic structure. Based on the exchange bias effect, the magnetic moments of the first ferromagnetic layer and the second ferromagnetic layer are pinned, which can make the first ferromagnetic structure and the second ferromagnetic structure generate a stable stray field to assist in flipping the free layer, increasing the data writing stability of the magnetic storage element. Among them, the materials of the first antiferromagnetic layer and the second antiferromagnetic layer can be platinum-manganese alloy or iridium-manganese alloy, etc. The materials of the first antiferromagnetic layer and the second antiferromagnetic layer can be the same or different, but the order of each film layer in the first ferromagnetic structure needs to be the same as the order of each film layer in the second ferromagnetic structure, such as ferromagnetic layer / antiferromagnetic layer from top to bottom or antiferromagnetic layer / ferromagnetic layer from top to bottom.

[0058] Under the pinning effect of the antiferromagnetic layer, the ferromagnetic layer exhibits the same magnetic moment as the antiferromagnetic layer. Therefore, in order to make the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer opposite, the magnetic moment directions of the first antiferromagnetic layer and the second antiferromagnetic layer can be made opposite by means such as annealing, using different materials, using the same material but different thicknesses, etc.

[0059] Specifically, the first antiferromagnetic layer and the second antiferromagnetic layer can be made of the same material. While annealing the first antiferromagnetic layer and the second antiferromagnetic layer in segments, a magnetic field in the opposite direction is applied to make the magnetic moments of the first antiferromagnetic layer and the second antiferromagnetic layer opposite; alternatively, the first antiferromagnetic layer and the second antiferromagnetic layer can be set with different blocking temperatures. For example, the first antiferromagnetic layer and the second antiferromagnetic layer are made of the same material but have different thicknesses. The greater the thickness, the higher the blocking temperature. Or the first antiferromagnetic layer and the second antiferromagnetic layer can also be made of different materials. Since the materials are different, the blocking temperatures will also be different. Taking the case where the designed blocking temperature of the first antiferromagnetic layer is higher than that of the second antiferromagnetic layer as an example, first, a magnetic field is applied to the first antiferromagnetic layer and the second antiferromagnetic layer for high-temperature annealing. The annealing temperature is higher than the blocking temperature of the first antiferromagnetic layer, and the magnetic moments of the two are rearranged. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer and the second antiferromagnetic layer are fixed. Then, the annealing temperature is applied again. At this time, the annealing temperature is between the blocking temperature of the first antiferromagnetic layer and the blocking temperature of the second antiferromagnetic layer, and a magnetic field in the opposite direction to the first annealing is applied simultaneously. The magnetic moment of the second antiferromagnetic layer is rearranged again. Since the blocking temperature of the first antiferromagnetic layer is higher than the annealing temperature, the magnetic moment does not change. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer and the second antiferromagnetic layer are opposite, and thus the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer pinned are opposite.

[0060] The blocking temperature is the temperature at which the exchange bias effect between the ferromagnetic layer and the antiferromagnetic layer disappears. When the annealing temperature exceeds the blocking temperature, the magnetic order of the antiferromagnetic layer becomes disordered, and a magnetic field can be applied to make the magnetic moments inside the antiferromagnetic layer arranged in an orderly manner.

[0061] The embodiment of the present application also provides a third magnetic storage element, which is mainly different from the first or second magnetic storage element in that: a first conductive part is also correspondingly arranged below the spin-orbit torque layer; the write current flows through the first ferromagnetic structure, the spin-orbit torque layer and the first conductive part in sequence to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure is weakened, and the stray field generated by the second ferromagnetic structure assists the magnetic storage element to flip to the first resistance state; the write current flows through the second ferromagnetic structure, the spin-orbit torque layer and the first conductive part in sequence to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure is weakened, and the stray field generated by the first ferromagnetic structure assists the magnetic storage element to flip to the second resistance state.

[0062] Reference Figure 3 and Figure 4, the first conductive part includes a first conductive via 100 and a second conductive via 110. The first conductive via 100 is disposed in the spacer layer 20, and the second conductive via 110 is disposed in the substrate 10. The first conductive via 100 and the second conductive via 110 are electrically connected to form the first conductive part, and the spin-orbit torque layer 30 is electrically connected to the outside through the first conductive part; in addition, a first conductive part directly penetrating the substrate 10 and the spacer layer 20 can also be disposed below the spin-orbit torque layer 30, and the specific composition of the first conductive part is not limited herein.

[0063] Continue to refer to Figure 4 , the first write current I w1 flows in from the first ferromagnetic structure 50, passes through the spin-orbit torque layer 30, and flows out from the first conductive part to form the first write path; the second write current I w2 flows in from the second ferromagnetic structure 60, passes through the spin-orbit torque layer 30, and flows out from the first conductive part to form the second write path. In the initial state of the magnetic storage element, the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite, and at this time, the stray field received by the free layer is in a balanced or approximately balanced state; when the write current I w1 flows through the first ferromagnetic structure 50 via the first write path, the first ferromagnetic structure 50 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the second ferromagnetic structure 60 dominates, assisting the free layer to flip to the first resistance state antiparallel to the magnetic moment of the reference layer; similarly, when the write current I w2 flows through the second ferromagnetic structure 60 via the second write path, the second ferromagnetic structure 60 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the first ferromagnetic structure 50 dominates, assisting the free layer to flip to the second resistance state parallel to the magnetic moment of the reference layer. By making the write current flow through the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to generate stray fields in opposite directions to assist the free layer to flip, the flipping efficiency of the free layer can be improved and the power consumption of the magnetic storage element can be reduced.

[0064] On the other hand, the embodiment of the present application also provides a manufacturing method of a magnetic storage element. For the flowchart of the manufacturing method of the first magnetic storage element, refer to Figure 5 , including the following steps: Step S10: Form a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure on the substrate. The first ferromagnetic structure and the second ferromagnetic structure are independently formed on both sidewalls of the spacer layer; wherein, the first ferromagnetic structure includes a first ferromagnetic layer, the second ferromagnetic structure includes a second ferromagnetic layer, and the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite; Step S20: Sequentially form a spin-orbit torque layer and a magnetic tunnel junction above the spacer layer; the top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin-orbit torque layer and are electrically connected to the spin-orbit torque layer.

[0065] Among them, the material of the substrate can be a semiconductor material, such as silicon, silicon carbide, gallium nitride, aluminum nitride, etc., or an insulating material, such as germanium, etc.; it can also be a logic substrate containing a logic circuit inside.

[0066] The first ferromagnetic structure and the second ferromagnetic structure can be ferromagnetic layers, and the materials are ferromagnetic materials such as permalloy, cobalt-iron alloy, etc. The materials of the two can be the same or different, and the magnetic moments of the first ferromagnetic layer and the second ferromagnetic layer are opposite; the first ferromagnetic structure and the second ferromagnetic structure can also be composite film layer structures. The first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer; the order of the film layers in the first ferromagnetic structure is the same as the order of the film layers in the second ferromagnetic structure. The first antiferromagnetic layer and the second antiferromagnetic layer can pin the magnetic moments of the first ferromagnetic layer and the second ferromagnetic layer based on the exchange bias effect, so that the first ferromagnetic structure and the second ferromagnetic structure generate a stable stray field to assist in flipping the free layer, so as to increase the data writing stability of the magnetic storage element. Among them, the materials of the first antiferromagnetic layer and the second antiferromagnetic layer can be platinum-manganese alloy or iridium-manganese alloy, etc. The materials of the first antiferromagnetic layer and the second antiferromagnetic layer can be the same or different, but the order of the film layers in the first ferromagnetic structure needs to be the same as the order of the film layers in the second ferromagnetic structure, such as ferromagnetic layer / antiferromagnetic layer from top to bottom or antiferromagnetic layer / ferromagnetic layer from top to bottom.

[0067] Under the pinning effect of the antiferromagnetic layer, the ferromagnetic layer exhibits the same magnetic moment as the antiferromagnetic layer. Therefore, in order to make the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer opposite, the magnetic moment directions of the first antiferromagnetic layer and the second antiferromagnetic layer can be made opposite by annealing while applying a magnetic field, using different materials, using the same material but different thicknesses, etc.

[0068] The spacer layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc. The first ferromagnetic structure and the second ferromagnetic structure are formed on both sides of the spacer layer, which is convenient for preparation and does not require complex preparation steps such as digging holes, and the process is simple.

[0069] Regarding step S10, the embodiments of the present disclosure provide at least the following several manufacturing methods for forming the spacer layer, the first ferromagnetic structure and the second ferromagnetic structure, which will be specifically described below in conjunction with the drawings.

[0070] First, a first manufacturing method for forming the spacer layer, the first ferromagnetic structure and the second ferromagnetic structure in the manufacturing method of the magnetic storage element is provided. Step S10 is specifically: forming a spacer layer and a ferromagnetic structure film layer wrapping the spacer layer on the substrate, and removing part of the ferromagnetic structure film layer so that the ferromagnetic structure film layer forms two independent first ferromagnetic structures and second ferromagnetic structures on both sides of the spacer layer, and the magnetic moment directions of the first ferromagnetic layer in the first ferromagnetic structure and the second ferromagnetic layer in the second ferromagnetic structure are opposite.

[0071] Among them, the specific steps for removing part of the ferromagnetic structure film layer are as follows: form a spacer layer and a ferromagnetic structure film layer wrapping the spacer layer on the substrate, deposit a first dielectric layer above the ferromagnetic structure film layer to wrap the ferromagnetic structure film layer, and polish the first dielectric layer using a chemical mechanical polishing process until the top surface of the spacer layer is exposed. At this time, the remaining ferromagnetic structure film layer forms independent first and second ferromagnetic structures on both sides of the spacer layer, and the first and second ferromagnetic layers do not contact each other.

[0072] The ferromagnetic structure film layer can be a single film layer structure containing a ferromagnetic layer or a composite structure film layer. The first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer. By utilizing the exchange bias effect between the antiferromagnetic layer and the ferromagnetic layer, the magnetic moment of the ferromagnetic layer is pinned, enabling the first and second ferromagnetic structures to generate a stable stray field to assist in flipping the free layer, thereby increasing the data writing stability of the magnetic storage element. Among them, the order of the film layers in the first ferromagnetic structure is the same as that in the second ferromagnetic structure. For example, from top to bottom, they are both ferromagnetic layer / antiferromagnetic layer or both antiferromagnetic layer / ferromagnetic layer. Here, it is not restricted whether the ferromagnetic structure film layer must be a composite structure.

[0073] In the manufacturing method of this embodiment, to make the magnetic moment directions of the first and second ferromagnetic layers opposite, after forming the first and second ferromagnetic structures, when annealing the first and second ferromagnetic structures respectively, a magnetic field with opposite directions is applied to make the magnetic moments of the first and second ferromagnetic layers opposite.

[0074] The first dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc. The remaining first dielectric layer can be retained to form the dielectric layer 90 in Figure 6 to protect the sidewalls of the first ferromagnetic structure 50 and the second ferromagnetic structure 60, or it can be selectively removed.

[0075] Continue to refer to Figure 6 , and bottom vias 80 can also be provided in the substrate 10, corresponding to the first ferromagnetic structure 50 and the second ferromagnetic structure 60 respectively, to achieve electrical connection with an external circuit for data writing and reading.

[0076] The bottom vias 80 are composed of a conductive material. When depositing the ferromagnetic structure film layer, it can also be synchronously deposited in the bottom vias 80 to increase the contact area between the ferromagnetic layer and the antiferromagnetic layer, thereby increasing the intensity of the stray field, further improving the flipping efficiency of the free layer, and reducing the power consumption of the magnetic storage element. Moreover, by utilizing the pinning effect of the antiferromagnetic layer on the magnetic moment of the ferromagnetic layer, the stability of the stray field of the magnetic storage element can also be improved.

[0077] The present application provides a second method for manufacturing a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in a method for manufacturing a magnetic storage element: a ferromagnetic layer and a first dielectric layer are sequentially formed from bottom to top on a substrate; a part of the first dielectric layer is removed, and a groove is formed on the first dielectric layer. The remaining first dielectric layers on both sides of the groove have different heights and are both higher than the bottom surface of the groove; the ferromagnetic layer is etched using the remaining first dielectric layer as a mask to form independent first and second ferromagnetic structures, wherein the remaining first and second ferromagnetic layers have different thicknesses; a second dielectric layer is filled between the first ferromagnetic structure and the second ferromagnetic structure to form a spacer layer.

[0078] Among them, a part of the first dielectric layer is removed, and a groove is formed on the first dielectric layer. The remaining first dielectric layers on both sides of the groove have different heights and are both higher than the bottom surface of the groove. Specifically, the height difference between the top surface of the remaining first dielectric layer on one side of the groove and the bottom surface of the groove is higher than the thickness of the ferromagnetic layer, and the height difference between the top surface of the remaining first dielectric layer on the other side of the groove and the bottom surface of the groove is lower than the thickness of the ferromagnetic layer and higher than the thickness from the bottom surface of the groove to the substrate, so as to ensure that when the ferromagnetic layer is etched using the remaining first dielectric layer as a mask subsequently, first and second ferromagnetic layers with different thicknesses can be formed.

[0079] The finally obtained first and second ferromagnetic layers have different thicknesses. For example, the thickness of the first ferromagnetic layer is greater than that of the second ferromagnetic layer. Therefore, the coercive field for flipping the magnetic moment of the first ferromagnetic layer is greater than the coercive field for flipping the magnetic moment of the second ferromagnetic layer. To make the magnetic moments of the first and second ferromagnetic layers opposite, the first and second ferromagnetic layers need to be annealed twice: when annealing for the first time, a magnetic field in a certain direction is applied simultaneously, and the magnitude of this magnetic field is greater than the coercive field of the first ferromagnetic layer. The magnetic moment directions of the first and second ferromagnetic layers are both fixed in the same direction. At this time, annealing is carried out for the second time, and a magnetic field opposite to the direction of the magnetic field during the first annealing is applied simultaneously. The magnitude of this magnetic field is greater than the coercive field of the second ferromagnetic layer and less than the coercive field of the first ferromagnetic layer. The magnetic moment direction of the first ferromagnetic layer is not affected, and the magnetic moment of the second ferromagnetic layer is fixed in the direction opposite to that of the first ferromagnetic layer.

[0080] A second dielectric layer is filled in the gap between the first ferromagnetic structure and the second ferromagnetic structure to form a spacer layer. The second dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc.

[0081] The present application embodiment provides a third method for manufacturing a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure in a method for manufacturing a magnetic storage element: a first ferromagnetic layer and a second ferromagnetic layer made of different materials are respectively formed on a substrate, and there is a gap between the first ferromagnetic layer and the second ferromagnetic layer; a first dielectric layer is deposited in the gap to form a spacer layer.

[0082] In the manufacturing method of the magnetic storage element according to the embodiment of the present application, a first ferromagnetic layer and a second ferromagnetic layer made of different materials are respectively formed on a substrate. The specific steps are as follows: deposit and etch a first ferromagnetic material on the substrate to form the first ferromagnetic layer, expose a part of the substrate, and continue to deposit and etch a second ferromagnetic material different from the first ferromagnetic material on the exposed substrate to form the second ferromagnetic layer, exposing the substrate between the first ferromagnetic layer and the second ferromagnetic layer. Among them, the first dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc.

[0083] Since the materials of the first ferromagnetic layer and the second ferromagnetic layer are different, the coercive fields for the magnetic moment reversal of the two are different. For example, the coercive field of the first ferromagnetic material is greater than that of the second ferromagnetic material. Therefore, the coercive field for reversing the magnetic moment of the first ferromagnetic layer is greater than that for reversing the magnetic moment of the second ferromagnetic layer. To make the magnetic moment of the first ferromagnetic layer opposite to that of the second ferromagnetic layer, it is necessary to anneal the first ferromagnetic layer and the second ferromagnetic layer twice. When annealing for the first time, a magnetic field in a certain direction is applied simultaneously, and the magnitude of this magnetic field is greater than the coercive field of the first ferromagnetic layer. The magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are both fixed in the same direction. At this time, perform the second annealing, and apply a magnetic field in the direction opposite to that of the first annealing simultaneously. The magnitude of this magnetic field is greater than the coercive field of the second ferromagnetic layer and less than the coercive field of the first ferromagnetic layer. The magnetic moment direction of the first ferromagnetic layer is not affected, and the magnetic moment of the second ferromagnetic layer is fixed in the direction opposite to that of the first ferromagnetic layer.

[0084] Combined with Figures 7 to 8 , a fourth manufacturing method for forming the spacer layer 20, the first ferromagnetic structure 50, and the second ferromagnetic structure 60 in the manufacturing method of the magnetic storage element is provided: a ferromagnetic layer 130, an antiferromagnetic layer 140, and a first dielectric layer 120 are sequentially formed on the substrate 10 from bottom to top; remove a part of the first dielectric layer 120, form a groove on the first dielectric layer 120, and the remaining first dielectric layer 120 on both sides of the groove has different heights and is higher than the bottom surface of the groove; use the remaining first dielectric layer 120 as a mask to etch the antiferromagnetic layer 140 and the ferromagnetic layer 130 to form independent first ferromagnetic structure 50 and second ferromagnetic structure 60, where the thicknesses of the remaining first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are different; fill a second dielectric layer between the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to form the spacer layer 20.

[0085] Refer to Figure 7, remove part of the first dielectric layer 120, and form a groove on the first dielectric layer 120. The remaining first dielectric layers 120 on both sides of the groove have different heights and are both higher than the bottom surface of the groove. Specifically, the height difference between the top surface of the remaining first dielectric layer 120 on one side of the groove and the bottom surface of the groove is not less than the sum of the thicknesses of the antiferromagnetic layer 140 and the ferromagnetic layer 130, and the height difference between the top surface of the remaining first dielectric layer 120 on the other side of the groove and the bottom surface of the groove is not less than the thickness of the ferromagnetic layer 130 and not higher than the sum of the thicknesses of the antiferromagnetic layer 140 and the ferromagnetic layer 130, so as to ensure that when the antiferromagnetic layer 140 is etched using the remaining first dielectric layer 120 as a mask later, the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 with different thicknesses can be formed.

[0086] Refer to Figure 8 , use the remaining first dielectric layer 120 as a mask to etch the antiferromagnetic layer 140 and the ferromagnetic layer 130 until the connection between the antiferromagnetic layer 140 and the ferromagnetic layer 130 on both sides of the groove is cut off, forming independent first ferromagnetic structure 50 and second ferromagnetic structure 60. Since the heights on both sides of the groove are inconsistent, the finally etched first antiferromagnetic layer 52 and second antiferromagnetic layer 62 have different thicknesses. For example, the thickness of the first antiferromagnetic layer 52 is greater than the thickness of the second antiferromagnetic layer 62. At this time, a high-temperature annealing with a magnetic field is performed on the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62. Since the greater the thickness, the higher the blocking temperature, the initially applied annealing temperature is higher than the blocking temperature of the first antiferromagnetic layer 52, and the magnetic moments of the two are rearranged. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are fixed in a certain same direction. Then, the annealing temperature is applied again while applying a magnetic field in the opposite direction to the first annealing. At this time, the annealing temperature is between the blocking temperature of the first antiferromagnetic layer 52 and the blocking temperature of the second antiferromagnetic layer 62. The magnetic moment of the second antiferromagnetic layer 62 is rearranged again. Since the blocking temperature of the first antiferromagnetic layer 52 is higher than the annealing temperature, the magnetic moment does not change. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are opposite, and thus the magnetic moment directions of the pinned first ferromagnetic layer and the second ferromagnetic layer are opposite.

[0087] The blocking temperature is the temperature at which the exchange bias effect between the ferromagnetic layer and the antiferromagnetic layer disappears. When the annealing temperature exceeds the blocking temperature, the magnetic order of the antiferromagnetic layer becomes disordered, and a magnetic field can be applied to make the magnetic moments inside the antiferromagnetic layer arranged orderly.

[0088] Such as Figure 8As shown, a second dielectric layer is filled in the gap between the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to form a spacer layer 20. The second dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc. Further, the second dielectric layer also covers the upper parts of the first ferromagnetic structure 50 and the second ferromagnetic structure 60. Through an opening process, top vias 150 are respectively formed in the second dielectric layer above the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to respectively realize the electrical connection between the first ferromagnetic structure 50 and the second ferromagnetic structure 60 and the spin-orbit torque layer 30.

[0089] Combined with Figures 9 to 11 , a fifth method for manufacturing the spacer layer 20, the first ferromagnetic structure and the second ferromagnetic structure in the manufacturing method of the magnetic storage element is provided: an antiferromagnetic layer 140 and a first dielectric layer 120 are sequentially formed on the substrate 10 from bottom to top; a part of the first dielectric layer 120 is removed, and a groove is formed on the first dielectric layer 120. The remaining first dielectric layers 120 on both sides of the groove have different heights and are both higher than the bottom surface of the groove; the antiferromagnetic layer 140 is etched using the remaining first dielectric layer 120 as a mask to form an independent first antiferromagnetic layer 52 and a second antiferromagnetic layer 62; a second dielectric layer is filled between the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 to form a spacer layer 20; a first ferromagnetic layer 51 and a second ferromagnetic layer 61 are formed above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62, wherein the remaining first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 have different thicknesses.

[0090] Referring to Figure 9 , a part of the first dielectric layer 120 is removed, and a groove is formed on the first dielectric layer 120. The remaining first dielectric layers 120 on both sides of the groove have different heights and are both higher than the bottom surface of the groove. Specifically, the height difference between the top surface of the remaining first dielectric layer 120 on one side of the groove and the bottom surface of the groove is higher than the thickness of the antiferromagnetic layer 140, and the height difference between the top surface of the remaining first dielectric layer 120 on the other side of the groove and the bottom surface of the groove is lower than the thickness of the antiferromagnetic layer 140 and higher than the thickness between the bottom surface of the groove and the substrate 10, so as to ensure that when the antiferromagnetic layer 140 is etched using the remaining first dielectric layer 120 as a mask, the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 with different thicknesses can be formed; the antiferromagnetic layer 140 is etched using the remaining first dielectric layer 120 as a mask until the connection between the antiferromagnetic layers 140 on both sides of the groove is cut off to form an independent first antiferromagnetic layer 52 and a second antiferromagnetic layer 62.

[0091] Referring to Figure 10 and Figure 11, a first ferromagnetic layer 51 and a second ferromagnetic layer 61 are formed above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62. The steps include: sequentially depositing a ferromagnetic layer 130 and a third dielectric layer (not shown in the figure) above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62, and removing a part of the third dielectric layer and the ferromagnetic layer 130 by a chemical mechanical polishing process until the top of the spacer layer 20 is exposed. The remaining first ferromagnetic layer 51 and the first antiferromagnetic layer 52 form a first ferromagnetic structure, and the remaining second ferromagnetic layer 61 and the second antiferromagnetic layer 62 form a second ferromagnetic structure; the remaining third dielectric layer forms a dielectric layer 90. Among them, the third dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc.

[0092] After forming the first ferromagnetic structure and the second ferromagnetic structure, an annealing treatment is performed on the first ferromagnetic structure and the second ferromagnetic structure. Since the thicknesses of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are different, for example, the thickness of the first antiferromagnetic layer 52 is greater than the thickness of the second antiferromagnetic layer 62. At this time, a high-temperature annealing with a magnetic field is performed on the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62. Since the greater the thickness, the higher the blocking temperature, the initially applied annealing temperature is higher than the blocking temperature of the first antiferromagnetic layer 52, and the magnetic moments of the two are rearranged. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are fixed. Then, the annealing temperature is applied again while applying a magnetic field in the opposite direction to the first annealing. At this time, the annealing temperature is between the blocking temperature of the first antiferromagnetic layer 52 and the blocking temperature of the second antiferromagnetic layer 62, and the magnetic moment of the second antiferromagnetic layer 62 is rearranged again. Since the blocking temperature of the first antiferromagnetic layer 52 is higher than the annealing temperature, the magnetic moment does not change. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are opposite, and thus the magnetic moment directions of the pinned first ferromagnetic layer 51 and the second ferromagnetic layer 61 are opposite.

[0093] Combined Figures 12 to 14 , a sixth method for manufacturing the spacer layer 20, the first ferromagnetic structure, and the second ferromagnetic structure in the manufacturing method of the magnetic storage element is provided: a first antiferromagnetic layer 52 and a second antiferromagnetic layer 62 made of different materials are respectively formed on the substrate 10, and there is a gap between the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62; a first dielectric layer is deposited in the gap to form the spacer layer 20; a first ferromagnetic layer 51 and a second ferromagnetic layer 61 are formed above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62.

[0094] In the manufacturing method of the magnetic storage element according to the embodiment of the present application, referring to Figure 12, a first antiferromagnetic layer 52 and a second antiferromagnetic layer 62 made of different materials are respectively formed on a substrate 10. The specific steps are as follows: deposit and etch a first antiferromagnetic material (not shown in the figure) on the substrate 10 to form the first antiferromagnetic layer 52, expose part of the substrate 10, and continue to deposit and etch a second antiferromagnetic material (not shown in the figure) with a material different from that of the first antiferromagnetic material on the exposed substrate 10 to form the second antiferromagnetic layer 62, exposing the substrate 10 between the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62; wherein, the thicknesses of the first antiferromagnetic material and the second antiferromagnetic material can be the same or different.

[0095] Refer to Figure 13 , a first dielectric layer (not shown in the figure) is deposited in the gap between the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 to form a spacer layer 20. Among them, the first dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc.

[0096] Refer to Figure 13 and Figure 14 , a first ferromagnetic layer 51 and a second ferromagnetic layer 61 are formed above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62. The steps include: sequentially depositing a ferromagnetic layer 130 and a second dielectric layer (not shown in the figure) above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62, and using a chemical mechanical polishing process to remove part of the second dielectric layer and the ferromagnetic layer 130 until the top of the spacer layer 20 is exposed. The remaining first ferromagnetic layer 51 and the first antiferromagnetic layer 52 form a first ferromagnetic structure, and the remaining second ferromagnetic layer 61 and the second antiferromagnetic layer 62 form a second ferromagnetic structure; the remaining second dielectric layer forms a dielectric layer 90.

[0097] After the first ferromagnetic structure and the second ferromagnetic structure are formed, annealing treatment is performed on the first ferromagnetic structure and the second ferromagnetic structure. Since the materials of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are different, the blocking temperatures of different materials are different. For example, the blocking temperature of the first antiferromagnetic layer 52 is greater than the blocking temperature of the second antiferromagnetic layer 62. At this time, a magnetic field is applied for high-temperature annealing of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62. The initially applied annealing temperature is higher than the blocking temperature of the first antiferromagnetic layer 52, and the magnetic moments of the two are rearranged. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are fixed. The annealing temperature is applied again. At this time, the annealing temperature is between the blocking temperature of the first antiferromagnetic layer 52 and the blocking temperature of the second antiferromagnetic layer 62, and a magnetic field in the opposite direction to that during the first annealing is applied at the same time. The magnetic moment of the second antiferromagnetic layer 62 is rearranged again. Since the blocking temperature of the first antiferromagnetic layer 52 is higher than the annealing temperature, the magnetic moment does not change. After the temperature drops, the magnetic moment directions of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62 are opposite, and thus the magnetic moment directions of the pinned first ferromagnetic layer 51 and the second ferromagnetic layer 61 are opposite.

[0098] Combined Figures 15 to 17 , a seventh method for manufacturing a spacer layer 20, a first ferromagnetic structure, and a second ferromagnetic structure in a method for manufacturing a magnetic storage element is provided: deposit and etch a ferromagnetic layer on a substrate 10 to expose a part of the substrate 10, forming an independent first ferromagnetic layer 51 and a second ferromagnetic layer 61; deposit a first dielectric layer in the gap between the first ferromagnetic layer 51 and the second ferromagnetic layer 61 to form the spacer layer 20; form a first antiferromagnetic layer 52 and a second antiferromagnetic layer 62 above the first ferromagnetic layer 51 and the second ferromagnetic layer 61.

[0099] Refer to Figure 15 , deposit a first dielectric layer (not shown in the figure) in the gap between the first ferromagnetic layer 51 and the second ferromagnetic layer 61 to form the spacer layer 20. The first dielectric layer is an insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, etc.

[0100] In the method for manufacturing a magnetic storage element according to an embodiment of the present application, with reference to Figure 15 and Figure 16 , form a first antiferromagnetic layer 52 and a second antiferromagnetic layer 62 above the first ferromagnetic layer 51 and the second ferromagnetic layer 61. The specific steps are as follows: deposit and etch a first antiferromagnetic material 141 on the first ferromagnetic layer 51 to expose the top surface of the second ferromagnetic layer 61, and continue to deposit and etch a second antiferromagnetic material 142 different from the first antiferromagnetic material 141 on the exposed second ferromagnetic layer 61 to expose the top surface of the first antiferromagnetic layer 52; wherein, the thicknesses of the first antiferromagnetic material 141 and the second antiferromagnetic material 142 may be the same or different.

[0101] Refer to Figure 17 , deposit a second dielectric layer (not shown in the figure) above the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62, and use a chemical mechanical polishing process to remove part of the second dielectric layer until the top of the spacer layer 20 is exposed. The remaining first ferromagnetic layer 51 and the first antiferromagnetic layer 52 constitute a first ferromagnetic structure, and the remaining second ferromagnetic layer 61 and the second antiferromagnetic layer 62 constitute a second ferromagnetic structure; the remaining second dielectric layer constitutes a dielectric layer 90.

[0102] After forming the first ferromagnetic structure and the second ferromagnetic structure, anneal the first ferromagnetic structure and the second ferromagnetic structure. Here, based on the different materials of the first antiferromagnetic layer 52 and the second antiferromagnetic layer 62, the annealing method is the same as the annealing method in the sixth method for manufacturing a spacer layer, a first ferromagnetic structure, and a second ferromagnetic structure described above, and will not be elaborated here.

[0103] Regarding step S20, specifically: a spin-orbit torque film layer and a magnetic tunnel junction film layer are sequentially formed above the spacer layer; the spin-orbit torque film layer and the magnetic tunnel junction film layer are etched to form a spin-orbit torque layer and a magnetic tunnel junction. The top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin-orbit torque layer and are electrically connected to the spin-orbit torque layer. The finally formed structure can be referred to Figure 1 as shown.

[0104] The deposited spin-orbit torque film layer ( Figure 1 not shown in x Se 1-x )) is a material that can generate the spin-orbit torque effect, including platinum, palladium, hafnium, gold, tantalum, tungsten, iridium, or their alloys; or topological insulators, including bismuth selenide (Bi x Sb 1-x ), bismuth antimonide (Bi 2 Te 3 ), bismuth telluride-based materials (Bi,Sb) 2 Te 2 ), etc., where 0 < x < 1; it can also be a two-dimensional material, such as molybdenum disulfide (MoS

[0105] The magnetic tunnel junction film layer ( Figure 1 not shown in

[0106] The top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 formed by the manufacturing method of the embodiment of the present application are not higher than the top surface of the spin-orbit torque layer 30 to avoid short-circuiting of the magnetic tunnel junction 40. Continuing to refer to Figure 1 , the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are respectively electrically connected to the spin-orbit torque layer 30 to form an interconnected bottom electrode, which can solve the problem of increased resistance caused by etching damage of the spin-orbit torque layer 30, thereby reducing the bottom electrode resistance and further reducing the power consumption of the magnetic storage element. The electrical connection method used to form the interconnected bottom electrode here can be to form a conductive component electrical connection between the first ferromagnetic structure 50 and the second ferromagnetic structure 60 and the spin-orbit torque layer 30 respectively (such asFigure 8 the magnetic storage element shown), or the bottom electrode resistance can be further reduced by direct contact electrical connection (such as Figures 1 to 4 the magnetic storage element shown).

[0107] The top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 can be higher than the bottom surface of the spin-orbit torque layer 30. Specifically: A second dielectric layer is formed above the first ferromagnetic structure 50, the spacer layer 20, and the second ferromagnetic structure 60, and the second dielectric layer is etched until a groove is formed above the spacer layer 20. A spin-orbit torque film layer and a magnetic tunnel junction film layer are deposited and etched in the groove to form the spin-orbit torque layer 30 and the magnetic tunnel junction 40. Among them, the height of the deposited spin-orbit torque film layer needs to be higher than the top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60.

[0108] Furthermore, when etching to form the spin-orbit torque layer 30, the projected area of the spin-orbit torque layer 30 on the substrate 10 can be made larger than the projected area of the spacer layer 20 on the substrate 10, so that the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are in partial contact with the bottom surface of the spin-orbit torque layer 30, directly forming an interconnected bottom electrode to further reduce the bottom electrode resistance. Even further, the top surfaces of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 can be flush with the bottom surface of the spin-orbit torque layer 30. After forming the dielectric layer 90, the spin-orbit torque layer 30 and the magnetic tunnel junction 40 can be directly formed on the flat top surfaces of the first ferromagnetic structure 50, the spacer layer 20, and the second ferromagnetic structure 60, which can simplify the manufacturing process, avoid the performance damage of the magnetic storage element caused by the uneven bottom interface of the spin-orbit torque layer 30, and improve the yield.

[0109] In addition, the projected area of the spin-orbit torque layer 30 on the substrate 10 can be equal to the projected area of the magnetic tunnel junction 40 on the substrate 10. Based on the etching stop layer formed by the first ferromagnetic structure 50 and the second ferromagnetic structure 60, only one etching step can be used to obtain the spin-orbit torque layer 30 and the magnetic tunnel junction 40 simultaneously, saving one etching process and simplifying the manufacturing steps; moreover, there is no redundant spin-orbit torque layer 30 on both sides of the magnetic tunnel junction 40, which can further reduce the bottom electrode resistance and the power consumption of the magnetic storage element.

[0110] Reference Figure 2, in the magnetic storage element formed by the manufacturing method of the embodiment of the present application, the write current sequentially flows through the first ferromagnetic structure 50, the spin-orbit torque layer 30 and the magnetic tunnel junction 40 to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure 50 weakens, and the stray field generated by the second ferromagnetic structure 60 assists the magnetic storage element to flip to the first resistance state; the write current sequentially flows through the second ferromagnetic structure 60, the spin-orbit torque layer 30 and the magnetic tunnel junction 40 to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure 60 weakens, and the stray field generated by the first ferromagnetic structure 50 assists the magnetic storage element to flip to the second resistance state.

[0111] Specifically, the first write current Iw 1 flows in from the first ferromagnetic structure 50, passes through the spin-orbit torque layer 30 and the magnetic tunnel junction 40, and flows out from the top electrode 70 to form a first write path; the second write current Iw 2 flows in from the second ferromagnetic structure 60, passes through the spin-orbit torque layer 30 and the magnetic tunnel junction 40, and flows out from the top electrode 70 to form a second write path. In the initial state of the magnetic storage element, the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite, and at this time, the stray field received by the free layer is in a balanced or approximately balanced state; when the write current Iw 1 flows through the first ferromagnetic structure 50 through the first write path, the first ferromagnetic structure 50 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the second ferromagnetic structure 60 dominates and assists the free layer to flip to the first resistance state; similarly, when the write current Iw 2 flows through the second ferromagnetic structure 60 through the second write path, the second ferromagnetic structure 60 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the first ferromagnetic structure 50 dominates and assists the free layer to flip to the second resistance state. By making the write current generate stray fields with opposite directions when flowing through the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to assist the free layer to flip, the flipping efficiency of the free layer can be improved and the power consumption of the magnetic storage element can be reduced.

[0112] Among them, the first resistance state and the second resistance state are resistance states of two opposite states. For example, the first resistance state is the resistance state where the magnetic moments of the free layer and the reference layer are anti-parallel, and the second resistance state is the resistance state where the magnetic moments of the free layer and the reference layer are parallel; it can also be that the first resistance state is the resistance state where the magnetic moments of the free layer and the reference layer are parallel, and the second resistance state is the resistance state where the magnetic moments of the free layer and the reference layer are anti-parallel, which is not limited here.

[0113] Continue to refer to Figure 2, bottom vias 80 may be correspondingly formed below the first ferromagnetic structure 50 and the second ferromagnetic structure 60 respectively. The bottom vias 80 may be formed in the substrate to achieve electrical connection with an external circuit for data writing and reading. In addition, a conductive terminal (not shown in the figure) may be formed on both sides of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to input a writing current. There is no need to adopt complex process steps such as digging holes, which can simplify the manufacturing process. Here, the component for inputting the writing current is not limited.

[0114] In addition, to improve the storage density of the magnetic storage element, an embodiment of the present application further provides another method for forming the spin-orbit torque layer 30 and the magnetic tunnel junction 40, which can be used in the subsequent manufacturing processes of the foregoing first to third, fifth to seventh methods for forming the spacer layer 20, the first ferromagnetic structure 50, and the second ferromagnetic structure 60, and the further miniaturization of the magnetic tunnel junction 40 can be achieved by using a self-alignment process.

[0115] Combined with Figures 18 to 20 , the specific steps are as follows: After forming the spacer layer 20, the first ferromagnetic structure 50, and the second ferromagnetic structure 60 through step S10, the dielectric layers on both sides of the first ferromagnetic structure 50 and the second ferromagnetic structure 60 are removed, and a spin-orbit torque film layer 160, a magnetic tunnel junction film layer 170, and a hard mask layer 180 covering the first ferromagnetic structure 50, the spacer layer 20, and the second ferromagnetic structure 60 are deposited; the second dielectric layer 190 is deposited and etched to expose the top of the hard mask layer 180 facing the spacer layer 20; the hard mask layer 180 is etched laterally to laterally miniaturize it; based on the miniaturized hard mask layer 180, the spin-orbit torque film layer 160 and the magnetic tunnel junction film layer 170 are etched to form the spin-orbit torque layer 30 and the magnetic tunnel junction 40.

[0116] Combined with Figure 19 , the hard mask layer 180 is etched laterally to laterally miniaturize it. The lateral dimension of the miniaturized hard mask layer 180 needs to satisfy that the spin-orbit torque layer 30 formed after etching can be electrically connected to the first ferromagnetic structure 50 and the second ferromagnetic structure 60 respectively to reduce the bottom resistance of the magnetic storage element.

[0117] Refer to Figure 20, based on the etched spin - orbit torque film layer 160 and magnetic tunnel junction film layer 170 using the scaled - down hard mask layer 180, a spin - orbit torque layer 30 and a magnetic tunnel junction 40 are formed. During this process, the etching endpoint of the spin - orbit torque layer 30 stops on the first ferromagnetic structure 50 and the second ferromagnetic structure 60, effectively solving the problem of difficult endpoint stopping in the etching process of the spin - orbit torque layer 30 and reducing the etching process difficulty. Among them, the material of the hard mask layer 180 is metals such as titanium and tantalum and their nitrides or compounds. The scaled - down hard mask layer 180 can be used as the top electrode of the magnetic storage element and is connected to an external circuit to realize the writing and reading of stored data. By scaling down the hard mask layer 180, small - sized spin - orbit torque layer 30 and magnetic tunnel junction 40 can be obtained, facilitating the integration of magnetic storage elements.

[0118] The embodiment of the present application also provides another manufacturing method of a magnetic storage element. Different from the first manufacturing method: a first conductive part is further formed under the spin - orbit torque layer; the writing current flows through the first ferromagnetic structure, the spin - orbit torque layer, and the first conductive part in sequence to form a first writing path. When data is written through the first writing path, the stray field generated by the first ferromagnetic structure weakens, and the stray field generated by the second ferromagnetic structure assists the magnetic storage element to flip to the first resistance state; the writing current flows through the second ferromagnetic structure, the spin - orbit torque layer, and the first conductive part in sequence to form a second writing path. When data is written through the second writing path, the stray field generated by the second ferromagnetic structure weakens, and the stray field generated by the first ferromagnetic structure assists the magnetic storage element to flip to the second resistance state.

[0119] The magnetic storage element finally formed by the manufacturing method provided in this embodiment can be referred to Figure 3 and Figure 4 , the first conductive part includes a first conductive via 100 and a second conductive via 110. The first conductive via 100 is formed in the spacer layer 20, and the second conductive via 110 is formed in the substrate 10. The first conductive via 100 and the second conductive via 110 are electrically connected to form the first conductive part, and the spin - orbit torque layer 30 is electrically connected to the outside through the first conductive part; in addition, a first conductive part that directly penetrates the substrate 10 and the spacer layer 20 can also be formed under the spin - orbit torque layer 30. The specific composition of the first conductive part is not limited here.

[0120] Refer to Figure 4 , the first writing current Iw 1 flows in from the first ferromagnetic structure 50, passes through the spin - orbit torque layer 30, and flows out from the first conductive part to form the first writing path; the second writing current Iw 2Flowing in from the second ferromagnetic structure 60, passing through the spin-orbit torque layer 30, and flowing out from the first conductive part to form the second writing path. In the initial state of the magnetic storage element, the magnetic moment directions of the first ferromagnetic layer and the second ferromagnetic layer are opposite. At this time, the stray field received by the free layer is in a balanced or approximately balanced state; when the writing current Iw 1 flows through the first ferromagnetic structure 50 via the first writing path, the first ferromagnetic structure 50 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the second ferromagnetic structure 60 dominates, assisting the free layer to flip to the first resistance state where the magnetic moment is antiparallel to that of the reference layer; similarly, when the writing current Iw 2 flows through the second ferromagnetic structure 60 via the second writing path, the second ferromagnetic structure 60 heats up under the action of the current, the magnetic order becomes disordered, and the generated average stray field is weak. Therefore, the stray field generated by the first ferromagnetic structure 50 dominates, assisting the free layer to flip to the second resistance state where the magnetic moment is parallel to that of the reference layer. By making the writing current flow through the first ferromagnetic structure 50 and the second ferromagnetic structure 60 to generate stray fields with opposite directions, assisting the free layer to flip, the flipping efficiency of the free layer can be improved and the power consumption of the magnetic storage element can be reduced.

[0121] In this specification, the embodiments or implementation manners are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. The descriptions with reference to terms such as "one implementation manner", "some implementation manners", "illustrative implementation manner", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the implementation manner or example are included in at least one implementation manner or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same implementation manner or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more implementation manners or examples.

[0122] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A magnetic storage element, characterized in that: At least comprising a substrate, a spacer layer, a spin-orbit moment layer and a magnetic tunnel junction stacked in sequence from bottom to top, and a first ferromagnetic structure and a second ferromagnetic structure independently arranged on both side walls of the spacer layer; The top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin-orbit moment layer and are electrically connected to the spin-orbit moment layer; The first ferromagnetic structure includes a first ferromagnetic layer, and the second ferromagnetic structure includes a second ferromagnetic layer. The magnetic moments of the first ferromagnetic layer and the second ferromagnetic layer are in opposite directions.

2. The magnetic memory element according to claim 1, characterized in that The first ferromagnetic structure and the second ferromagnetic structure are both composite film layer structures, the first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer; The order of the film layers in the first ferromagnetic structure is the same as the order of the film layers in the second ferromagnetic structure.

3. The magnetic memory element according to claim 1, characterized in that A projected area of ​​the spacer layer on the substrate is smaller than a projected area of ​​the spin-orbit moment layer on the substrate, so that the first ferromagnetic structure and the second ferromagnetic structure are in contact with a bottom portion of the spin-orbit moment layer.

4. The magnetic memory element according to claim 3, characterized in that The top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are flush with the bottom surface of the spin-orbit moment layer.

5. The magnetic storage element according to any one of claims 1 to 4, characterized in that: The write current flows through the first ferromagnetic structure, the spin-orbit moment layer and the magnetic tunnel structure in sequence to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure is weakened, and the stray field generated by the second ferromagnetic structure assists the magnetic storage element to flip to a first resistance state. The write current flows through the second ferromagnetic structure, the spin-orbit moment layer and the magnetic tunnel structure in sequence to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure is weakened, and the stray field generated by the first ferromagnetic structure assists the magnetic storage element to flip to the second resistance state.

6. The magnetic storage element according to any one of claims 1 to 4, characterized in that: A first conductive portion is correspondingly arranged below the spin-orbit moment layer; The write current flows through the first ferromagnetic structure, the spin-orbit moment layer and the first conductive part in sequence to form a first write path. When data is written through the first write path, the stray field generated by the first ferromagnetic structure is weakened, and the stray field generated by the second ferromagnetic structure assists the magnetic storage element to flip to the first resistance state. The write current flows through the second ferromagnetic structure, the spin-orbit moment layer and the first conductive part in sequence to form a second write path. When data is written through the second write path, the stray field generated by the second ferromagnetic structure is weakened, and the stray field generated by the first ferromagnetic structure assists the magnetic storage element to flip to the second resistance state.

7. A method for manufacturing a magnetic storage element, characterized in that: The steps include: forming a spacer layer, a first ferromagnetic structure and a second ferromagnetic structure on a substrate, wherein the first ferromagnetic structure and the second ferromagnetic structure are independently formed on two side walls of the spacer layer; forming a spin-orbit moment layer and a magnetic tunnel junction in sequence above the spacer layer; The top surfaces of the first ferromagnetic structure and the second ferromagnetic structure are not higher than the top surface of the spin-orbit moment layer and are electrically connected to the spin-orbit moment layer; The first ferromagnetic structure includes a first ferromagnetic layer, the second ferromagnetic structure includes a second ferromagnetic layer, and the magnetic moments of the first ferromagnetic layer and the second ferromagnetic layer are in opposite directions.

8. The manufacturing method according to claim 7, characterized in that: The first ferromagnetic structure and the second ferromagnetic structure are both composite film layer structures, the first ferromagnetic structure further includes a first antiferromagnetic layer, and the second ferromagnetic structure further includes a second antiferromagnetic layer; The order of the film layers in the first ferromagnetic structure is the same as the order of the film layers in the second ferromagnetic structure.

9. The manufacturing method according to claim 8, characterized in that: The step of forming a spacer layer, a first ferromagnetic structure and a second ferromagnetic structure on a substrate, wherein the first ferromagnetic structure and the second ferromagnetic structure are independently formed on two side walls of the spacer layer, specifically includes: forming a ferromagnetic layer, an antiferromagnetic layer and a first dielectric layer in sequence from bottom to top on the substrate; Removing a portion of the first dielectric layer to form a groove on the first dielectric layer, wherein the remaining first dielectric layer on both sides of the groove has different heights and is higher than the bottom surface of the groove; Using the remaining first dielectric layer as a mask to etch the antiferromagnetic layer and the ferromagnetic layer to form an independent first ferromagnetic structure and a second ferromagnetic structure, wherein the remaining first antiferromagnetic layer and the second antiferromagnetic layer have different thicknesses; A second dielectric layer is filled between the first ferromagnetic structure and the second ferromagnetic structure to form the spacer layer.

10. The manufacturing method according to claim 9, characterized in that: The remaining first dielectric layers on both sides of the groove have different heights and are both higher than the bottom surface of the groove, specifically: The height difference between the top surface of the first dielectric layer remaining on one side of the groove and the bottom surface of the groove is not less than the sum of the thicknesses of the antiferromagnetic layer and the ferromagnetic layer, and the height difference between the top surface of the first dielectric layer remaining on the other side of the groove and the bottom surface of the groove is not less than the thickness of the ferromagnetic layer and not higher than the sum of the thicknesses of the antiferromagnetic layer and the ferromagnetic layer.

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