Magnetic storage unit and preparation method therefor

Abstract

Provided in the present invention is a magnetic storage unit. The magnetic storage unit comprises: a substrate layer, which comprises two bottom electrodes spaced apart from each other; a spin orbit torque layer, which is arranged on an upper surface of the substrate layer, wherein a spin orbit torque at least covers the two bottom electrodes; and a magnetic tunnel junction, which is arranged on an upper surface of the spin orbit torque layer, wherein the magnetic tunnel junction at least covers the range where the two bottom electrodes are located. The magnetic storage unit and the preparation method therefor provided in the present invention can provide a larger over-etch window, thereby significantly reducing short circuits caused by reverse sputtering, also decreasing the probability of a spin orbit torque layer being over etched and penetrated, and further improving the device yield.

Description

Magnetic storage unit and method for manufacturing the same Technical Field

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

[0002] As the next generation of non-volatile magnetic random access memory, spin-orbit moment magnetic memory uses spin-orbit moment as a way to write information, giving spin-orbit moment devices a writing speed in the nanosecond range. Its read and write separation mode makes it possible for spin-orbit moment magnetic memory to achieve unlimited writing.

[0003] The existing SOM magnetic memory cell architecture, whether two-terminal or three-terminal, is based on a magnetic tunnel junction where etching stops at the SOM material. This architectural design places high demands on etching, which directly affects the device's electrical performance:

[0004] First, the film layer where etching stops needs to be precisely controlled to reduce the impact of etching damage on the performance of the spin-orbit moment layer. The spin-orbit moment layer is very thin, only a few nanometers, and it is easy for it to be etched through during excessive etching, causing the orbital layer to break and the device to be scrapped.

[0005] Second, it is necessary to reduce short circuits in the magnetic tunnel junction (reduce metal backsputtering outside the barrier layer). A defect rate of at least 1000ppm is required at the device end for mass production to be possible. Short circuits are generally reduced by cutting the metal layer and then over-etching to remove backsputtering. However, the etching of the magnetic tunnel junction needs to stop on the spin-orbit moment layer. When etching stops, the area outside the magnetic tunnel junction is completely metal, which increases the difficulty of removing metal backsputtering.

[0006] Third, since the distance between the bottom electrodes is usually larger than the diameter of the tunnel junction, most of the track layer is not effectively utilized. Instead, the memory generates high heat and consumes large power during use due to the large resistance.

[0007] Summary of the Invention

[0008] The present invention provides a magnetic storage unit and a preparation method thereof, which can provide a larger over-etching window, significantly reduce the short circuit caused by back sputtering, and reduce the probability of the spin-orbit moment layer being over-etched and penetrated, thereby improving the device yield.

[0009] In a first aspect, the present invention provides a magnetic storage unit comprising:

[0010] a substrate layer, the substrate layer comprising two bottom electrodes spaced apart;

[0011] A spin-orbit moment layer is provided on the upper surface of the substrate layer, wherein the spin-orbit moment layer at least covers the two bottom electrodes;

[0012] A magnetic tunnel junction is provided on the upper surface of the spin-orbit moment layer, and the magnetic tunnel junction at least covers the range where the two bottom electrodes are located.

[0013] Optionally, an edge of the magnetic tunnel junction is aligned with an edge of the spin-orbit moment layer.

[0014] Optionally, the magnetic tunnel junction includes a ferromagnetic layer, a barrier layer and a pinning layer, and the ferromagnetic layer is located above the track layer and in direct contact with the track layer.

[0015] Optionally, it also includes:

[0016] A hard mask layer is disposed on an upper surface of the magnetic tunnel junction, and an edge of the hard mask layer is aligned with an edge of the magnetic tunnel junction.

[0017] Optionally, it also includes:

[0018] A magnetic layer is disposed on the upper surface of the hard mask layer, and an edge of the magnetic layer is aligned with an edge of the hard mask layer.

[0019] Optionally, the magnetic moment direction of the magnetic layer is located in the plane of the magnetic layer or in the normal direction of the magnetic layer.

[0020] Optionally, the two bottom electrodes are arranged along the long axis direction of the spin-orbit moment, or the arrangement direction of the two bottom electrodes forms an angle with the long axis direction.

[0021] Optionally, the magnetic moment direction of the free layer of the magnetic tunnel junction is arranged along the long axis direction of the free layer, or the magnetic moment direction of the free layer of the magnetic tunnel junction is arranged along the normal direction of the free layer.

[0022] In a second aspect, the present invention further provides a method for preparing a magnetic storage unit, the method comprising:

[0023] providing a substrate layer having two bottom electrodes;

[0024] forming a spin-orbit moment layer and a magnetic tunnel junction in sequence on the substrate layer;

[0025] The magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled to be no higher than the lower surface of the spin-orbit moment layer.

[0026] Optionally, etching the magnetic tunnel junction and the spin-orbit moment layer once using the same mask comprises:

[0027] forming a hard mask layer on the upper surface of the magnetic tunnel junction;

[0028] The hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled to be no higher than the lower surface of the spin-orbit moment.

[0029] Optionally, etching the hard mask layer, the magnetic tunnel junction, and the spin-orbit moment layer once using the same mask includes:

[0030] forming a magnetic layer on the upper surface of the hard mask layer;

[0031] The magnetization layer, the hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled to be no higher than the lower surface of the spin-orbit moment.

[0032] In the technical solution provided by the present invention, both the magnetic tunnel junction and the spin-orbit moment layer are covered by two bottom electrodes, which can effectively provide a larger over-etching window. While significantly reducing short circuits caused by back sputtering, it also reduces the probability of the spin-orbit moment layer being penetrated due to over-etching, thereby improving device yield. At the same time, because both the magnetic tunnel junction and the spin-orbit moment layer are covered by two bottom electrodes, the distance between the two bottom electrodes can be reduced during preparation, which is conducive to shortening the length of the spin-orbit moment layer, reducing energy consumption, reducing the thermal effect of current, and thus improving device life. In addition, the magnetic storage unit provided by the present invention has strong compatibility and can be directly connected to the underlying metal layer, reducing the series resistance in the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a structural diagram of a magnetic storage unit according to an embodiment of the present invention;

[0034] FIG2 is a top view of FIG1 ;

[0035] FIG3 is a structural diagram of a magnetic storage unit according to another exemplary embodiment of the present invention;

[0036] FIG4 is a structural diagram of a magnetic storage unit according to another exemplary embodiment of the present invention;

[0037] FIG5 is a structural diagram of a magnetic storage unit according to another exemplary embodiment of the present invention;

[0038] FIG6 is a top view of FIG5;

[0039] 7 is a flow chart of a method for preparing a magnetic storage unit according to another embodiment of the present invention;

[0040] FIG8 is a substrate structure in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0041] FIG9 is a structure for preparing a through hole on a substrate in a method for preparing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0042] FIG10 is a structure after preparing a bottom electrode in a method for preparing a magnetic memory cell according to another exemplary embodiment of the present invention;

[0043] FIG11 is a structure after preparing a spin-orbit moment layer, a magnetic tunnel junction, a hard mask, and a magnetization layer in a method for preparing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0044] FIG12 is a structure after etching the spin-orbit moment layer, magnetic tunnel junction, hard mask and magnetization layer in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0045] FIG13 is a structure after depositing a medium and planarizing in a method for preparing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0046] FIG14 is a structure after forming a top electrode in a method for forming a magnetic memory cell according to another exemplary embodiment of the present invention;

[0047] FIG15 is a substrate structure in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0048] FIG16 is a structure for preparing a through hole on a substrate in a method for preparing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0049] FIG17 is a structure after preparing a bottom electrode in a method for preparing a magnetic memory cell according to another exemplary embodiment of the present invention;

[0050] FIG18 is a structure after forming a spin-orbit moment layer, a magnetic tunnel junction, a hard mask, and a magnetization layer in a method for forming a magnetic storage unit according to another exemplary embodiment of the present invention;

[0051] FIG19 is a structure after etching the spin-orbit moment layer, magnetic tunnel junction, hard mask, and magnetization layer in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0052] FIG20 is a structure after depositing a medium and planarizing in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0053] FIG21 is a structure after forming a top electrode in a method for forming a magnetic memory cell according to another exemplary embodiment of the present invention;

[0054] FIG22 is a substrate structure in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0055] FIG23 is a structure for preparing a through hole on a substrate in a method for preparing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0056] FIG24 a shows a structure after a bottom electrode is formed in a method for manufacturing a magnetic memory cell according to another exemplary embodiment of the present invention;

[0057] Figure 24b is a top view of Figure 24a;

[0058] FIG25 is a structure after forming a spin-orbit moment layer, a magnetic tunnel junction, and a hard mask in a method for forming a magnetic storage unit according to another exemplary embodiment of the present invention;

[0059] FIG26 shows a structure after etching the spin-orbit moment layer, the magnetic tunnel junction, and the hard mask in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0060] FIG27 is a structure after depositing a medium and planarizing in a method for manufacturing a magnetic storage unit according to another exemplary embodiment of the present invention;

[0061] FIG. 28 shows a structure after forming a top electrode in a method for forming a magnetic memory cell according to another exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0063] An embodiment of the present invention provides a magnetic storage unit, as shown in FIG1-2 , including:

[0064] A substrate layer, comprising two bottom electrodes 1 spaced apart from each other;

[0065] In some embodiments, the substrate layer generally includes two bottom electrodes 1 and a dielectric. The top surfaces of the bottom electrode 1 and the dielectric have the same height. The bottom electrode material is a metal material such as W, TiN, Ta, or TaN.

[0066] A spin-orbit moment layer 2, arranged on the upper surface of the substrate layer, wherein the spin-orbit moment at least covers the two bottom electrodes 1;

[0067] In some embodiments, the spin-orbit moment layer 2 is generally made of heavy metals or topological materials with large spin Hall angles, such as W, Ta, Pt, or BiSe.

[0068] A magnetic tunnel junction 3 is provided on the upper surface of the spin-orbit moment layer 2 , and the magnetic tunnel junction 3 at least covers the area where the two bottom electrodes 1 are located.

[0069] In some embodiments, the tunnel junction generally includes a stacked structure formed by a free layer, a barrier layer, and a reference layer, and the free layer is located at the bottom layer of the tunnel junction.

[0070] In the technical solution provided by this embodiment, the magnetic tunnel junction 3 and the spin-orbit moment layer 2 both cover the two bottom electrodes 1, which can effectively provide a larger over-etching window. While significantly reducing the short circuit caused by back sputtering, it also reduces the probability of the spin-orbit moment layer 2 being penetrated due to over-etching, thereby improving the device yield. At the same time, because the magnetic tunnel junction 3 and the spin-orbit moment layer 2 both cover the two bottom electrodes 1, the distance between the two bottom electrodes 1 can be reduced during preparation, which is conducive to shortening the length of the spin-orbit moment layer 2, reducing energy consumption, reducing the thermal effect of current, and thus improving the device life. In addition, the magnetic storage unit provided by the present invention has strong compatibility and can be directly connected to the underlying metal layer, reducing the series resistance in the loop.

[0071] As an optional implementation, the edge of the magnetic tunnel junction 3 is aligned with the edge of the spin-orbit moment layer 2 .

[0072] In some embodiments, the edge of the magnetic tunnel junction 3 is aligned with the edge of the spin-orbit moment, so that the etching of the magnetic tunnel junction 3 and the spin-orbit moment can be completed in one etching process during the processing, which can effectively simplify the preparation process.

[0073] As an optional implementation, the magnetic tunnel junction includes a ferromagnetic layer, a barrier layer, and a pinning layer, and the ferromagnetic layer is located above the track layer and in direct contact with the track layer.

[0074] As an optional implementation, it also includes:

[0075] A hard mask layer 4 is provided on the upper surface of the magnetic tunnel junction 3 , and an edge of the hard mask layer 4 is aligned with an edge of the magnetic tunnel junction 3 .

[0076] In some embodiments, the hard mask material is Ta, TaN, TiN, etc. Aligning the edges of the hard mask layer 4 and the magnetic tunnel junction 3 with the edge of the spin-orbit moment allows the hard mask layer 4, the magnetic tunnel junction 3, and the spin-orbit moment to be etched in one step during processing, effectively simplifying the manufacturing process.

[0077] As an optional implementation, it also includes:

[0078] The magnetic layer 6 is disposed on the upper surface of the hard mask layer 4 , and an edge of the magnetic layer 6 is aligned with an edge of the hard mask layer 4 .

[0079] In some embodiments, the material of the magnetic layer 6 is a metal material such as Co or Fe. Aligning the edges of the magnetic layer 6, the hard mask layer 4, and the magnetic tunnel junction 3 with the edge of the spin-orbit moment allows the magnetic layer 6, the hard mask layer 4, the magnetic tunnel junction 3, and the spin-orbit moment to be etched in a single step during processing, effectively simplifying the manufacturing process.

[0080] As an optional implementation, the magnetic moment direction of the magnetic layer 6 is located in the plane of the magnetic layer 6 or in the normal direction of the magnetic layer 6 .

[0081] As an optional implementation, the two bottom electrodes 1 are arranged along the long axis direction of the spin-orbit moment, or the arrangement direction of the two bottom electrodes 1 forms an angle with the long axis direction.

[0082] As an optional implementation, the magnetic moment direction of the free layer of the magnetic tunnel junction 3 is arranged along the long axis direction of the free layer, or the magnetic moment direction of the free layer of the magnetic tunnel junction 3 is arranged along the normal direction of the free layer.

[0083] As shown in FIG3 , an exemplary embodiment is provided to exemplarily illustrate the technical solution of the present invention. The magnetic storage unit in FIG3 includes:

[0084] The device consists of a bottom electrode 1, a spin-orbit moment layer 2, a tunnel junction 3, a metal hard mask 4, an optional horizontal magnetic layer 6, and a top electrode 5, arranged in a sequence from bottom to top. The spin-orbit moment layer 2, tunnel junction 3, metal hard mask 4, and optional horizontal magnetic layer 6 have identical phase shapes and are formed by a single etching process. The etched shape is a long strip, and the bottom electrode 1 is covered by the tunnel junction. The magnetic tunnel junction 3 is magnetized perpendicular to the wafer substrate (Z), while the optional horizontal magnetic layer 6 is magnetized in the x-direction, providing a bias field for the magnetic tunnel junction 3 and enabling field-free switching of the tunnel junction. In this device, the long axis of the tunnel junction is aligned with the write current direction (x). Current flowing through the two bottom electrodes 1 generates a spin current with a magnetic moment in the y-direction. Combined with the horizontal magnetic field generated by the horizontal magnetic layer 600, this enables write operations. Current flowing through one end of the bottom electrode 1 and the top electrode 5 enables read operations. As a preferred embodiment, the material of the bottom electrode 100 is W, and the characteristic size is 40nm; the spin-orbit moment layer 200 is W, and the thickness is 3-5nm; the free layer\dielectric\reference layer materials of the magnetic tunnel junction 300 are CoFeB, MgO, CoFeB, and the thickness of the free layer is 1-2nm; the size of the magnetic tunnel junction 300 is 300nm*60nm.

[0085] As shown in FIG4 , an exemplary embodiment is provided to exemplarily illustrate the technical solution of the present invention. The magnetic storage unit in FIG4 includes:

[0086] The device consists of a bottom electrode 1, a spin-orbit moment layer 2, a tunnel junction 3, a metal hard mask 4, an optional perpendicular magnetization layer 6, and a top electrode 5, arranged in a sequence from bottom to top. The spin-orbit moment layer 2, tunnel junction 3, metal hard mask 4, and optional perpendicular magnetization layer 6 have identical phase shapes and are formed by a single etching process. The etched shape is a long strip, and the bottom electrode 1 is covered by the tunnel junction. This magnetic storage unit is a type-X spin-orbit moment magnetic memory device. The magnetization direction of the magnetic tunnel junction 3 is along the wafer substrate surface (X), and the optional horizontal magnetization layer 6 is magnetized along the Z direction, providing a bias field for the magnetic tunnel junction 3, enabling field-free switching. In this device, the long axis of the tunnel junction is along the write current direction (X). Passing current through the two bottom electrodes 1 generates a spin current with a magnetic moment along the Y direction on the top surface of the orbital layer. Combined with the Z-direction magnetic field generated by the perpendicular magnetization layer 6, this device can be written. Passing current through one end of the bottom electrode 1 and the top electrode 5 enables a read operation. As a preferred embodiment, the material of the bottom electrode 1 is W, and the characteristic size is 50nm; the spin-orbit moment layer 200 is W, and the thickness is 3-5nm; the free layer\dielectric\reference layer materials of the magnetic tunnel junction 300 are CoFeB, MgO, CoFeB, and the thickness of the free layer is 2-4nm; the size of the magnetic tunnel junction 300 is 300nm*60nm.

[0087] As shown in FIG5-6, an exemplary embodiment is provided to exemplarily illustrate the technical solution of the present invention. The magnetic storage unit in FIG5-6 includes:

[0088] The structure consists of a bottom electrode 1, a spin-orbit moment layer 2, a tunnel junction layer 3, a metal hard mask layer 4, and a top electrode 5, arranged in this order from bottom to top. The spin-orbit moment layer 2, tunnel junction layer 3, and metal hard mask layer 4 have the same shape and are formed by a single etching process. The resulting shape is a long strip, and the bottom electrode 1 is covered by the tunnel junction. In this structure, a line connecting the centers of the two bottom electrodes 1 forms an angle with the X-direction. Among them, the magnetization direction of the magnetic tunnel junction 3 is perpendicular to the surface direction of the wafer substrate (along the Z direction); the long axis of the tunnel junction is along the X direction. After the write current is passed, the generated spin current has an angle with the X direction. In this case, no external magnetic field is required to achieve the write operation of the device. By passing current through the bottom electrode 1 and the top electrode 5 at one end, the read operation of the device can be achieved. As a preferred embodiment, the material of the bottom electrode 1 is W, and the characteristic size is 50nm; the spin-orbit moment layer 200 is W, and the thickness is 3~5nm; the free layer\dielectric\reference layer materials of the magnetic tunnel junction 300 are CoFeB, MgO, CoFeB, and the thickness of the free layer is 1~2nm; the MTJ size is 300nm*100nm.

[0089] An embodiment of the present invention further provides a method for preparing a magnetic storage unit, as shown in FIG7 , the method comprising:

[0090] Step 710, providing a substrate layer, wherein the substrate layer has two bottom electrodes;

[0091] Step 720, forming a spin-orbit moment layer and a magnetic tunnel junction in sequence on the substrate layer;

[0092] Step 730 , etching the magnetic tunnel junction and the spin-orbit moment layer once using the same mask, and controlling the etching end point to be no higher than the lower surface of the spin-orbit moment.

[0093] As an optional implementation manner, etching the magnetic tunnel junction and the spin-orbit moment layer once using the same mask includes:

[0094] forming a hard mask layer on the upper surface of the magnetic tunnel junction;

[0095] The hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled to be no higher than the lower surface of the spin-orbit moment.

[0096] As an optional embodiment, etching the hard mask layer, the magnetic tunnel junction, and the spin-orbit moment layer once using the same mask includes:

[0097] forming a magnetic layer on the upper surface of the hard mask layer;

[0098] The magnetization layer, the hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled to be no higher than the lower surface of the spin-orbit moment.

[0099] As shown in FIG8-14, an exemplary embodiment is provided to exemplarily illustrate the technical solution of the present invention. The method for preparing the magnetic storage unit in FIG8-14 includes:

[0100] As shown in FIG8 , dielectric layers 7 and 8 are deposited on a substrate forming a bottom electrode 9. The material of the bottom electrode 9 is generally Cu, Ta, TaN, TiN, etc., the material of the dielectric layer 7 is SiN, SiNC, Al2O3, etc., and the material of the dielectric 8 is SiO2, SiCO, etc.

[0101] As shown in FIG9 , bottom electrode through holes are prepared by photolithography and etching.

[0102] As shown in FIG10 , the bottom electrode material is deposited and planarized to prepare the bottom electrode 1 . The material of the bottom electrode can be a metal material such as W, TiN, TaN, etc. The planarization process can be achieved by chemical mechanical polishing or etching.

[0103] As shown in Figure 11, a spin-orbit moment layer 2, a tunnel junction 3, a hard mask 4, and an optional horizontal magnetization layer are deposited 6. The spin-orbit moment layer is made of materials with a self-selected Hall angle, such as W, Pt, Ta, and the optional horizontal magnetization layer is made of magnetic materials such as Co, Fe, CoFe, CoPt, and FeNi;

[0104] As shown in Figure 12, the tunnel junction is lithographically and etched to obtain the desired shape of the tunnel junction, and a dielectric protection layer 10 is deposited. After etching, the tunnel junction is in the shape of a long strip. The dielectric protection layer 10 can be made of materials such as SiN and SiNC.

[0105] As shown in Figure 13, a dielectric layer 11 is deposited and planarized. The material of the dielectric layer 11 is SiO2, SiCO, etc.

[0106] As shown in Figure 14, photolithography, etching, top electrode material filling and planarization are performed to prepare the top electrode 5. Usually, the material of the top electrode is a metal material such as Cu, W, TaN, etc.

[0107] As shown in FIG15-21, an exemplary embodiment is provided to exemplarily illustrate the technical solution of the present invention. The method for preparing the magnetic storage unit in FIG15-21 includes:

[0108] As shown in FIG15 , dielectric layers 7 and 8 are deposited on the substrate forming the bottom electrode 9. The material of the bottom electrode 9 is generally Cu, Ta, TaN, TiN, etc., the material of the dielectric layer 7 is SiN, SiNC, Al2O3, etc., and the material of the dielectric 8 is SiO2, SiCO, etc.

[0109] As shown in FIG16 , bottom electrode through holes are prepared by photolithography and etching;

[0110] As shown in FIG17 , the bottom electrode material is deposited and planarized to prepare the bottom electrode 1. The material of the bottom electrode can be a metal material such as W, TiN, TaN, etc. The planarization process can be achieved by chemical mechanical polishing or etching;

[0111] As shown in Figure 18, a spin-orbit moment layer 2, a tunnel junction 3, a hard mask 4, and an optional horizontal magnetization layer are deposited 6. The spin-orbit moment layer is made of materials with a self-selected Hall angle, such as W, Pt, Ta, and BiSe. The optional horizontal magnetization layer is made of a FePt or CoPt multilayer film or other magnetic multilayer film or alloy and other magnetic materials.

[0112] As shown in Figure 19, the tunnel junction is lithographically and etched to obtain the desired shape of the tunnel junction, and a dielectric protection layer is deposited. After etching, the tunnel junction is elliptical in shape. The dielectric protection layer 10 can be made of materials such as SiN and SiNC.

[0113] As shown in Figure 20, a dielectric layer 11 is deposited and planarized. The material of the dielectric layer 11 is SiO2, SiCO, etc.

[0114] As shown in Figure 21, photolithography, etching, top electrode material filling and planarization are performed to prepare the top electrode 5. Usually, the material of the top electrode is a metal material such as Cu, W, TaN, etc.

[0115] As shown in FIG22-28, an exemplary embodiment is provided to exemplarily illustrate the technical solution of the present invention. The method for preparing the magnetic storage unit in FIG22-28 includes:

[0116] As shown in FIG22 , dielectric layers 7 and 8 are deposited on the substrate forming the bottom electrode 9; the material of the bottom electrode 7 is generally Cu, Ta, TaN, TiN, etc., the material of the dielectric layer 8 is SiN, SiNC, Al2O3, etc., and the material of the dielectric 25 is SiO2, SiCO, etc.;

[0117] As shown in FIG23 , bottom electrode through holes are prepared by photolithography and etching;

[0118] As shown in FIG24a , the bottom electrode material is deposited and planarized to prepare the bottom electrode 1. The material of the bottom electrode can be a metal material such as W, TiN, TaN, etc., and the planarization process can be achieved by chemical mechanical polishing or etching. As shown in FIG24b , in this structure, there is a certain angle between the center line of the two bottom electrodes and the X direction.

[0119] As shown in Figure 25, there is a spin-orbit moment layer 2, a tunnel junction 3 and a hard mask 4. The spin-orbit moment layer is made of materials with a self-selected Hall angle, such as W, Pt, and Ta;

[0120] As shown in Figure 26, the tunnel junction is lithographically and etched to obtain the desired shape of the tunnel junction, and a dielectric protection layer is deposited. After etching, the tunnel junction is in the shape of an elongated strip. The dielectric protection layer 10 can be made of materials such as SiN and SiNC.

[0121] As shown in Figure 27, a dielectric layer 11 is deposited and planarized. The material of the dielectric layer 11 is SiO2, SiCO, etc.

[0122] As shown in Figure 28, photolithography, etching, top electrode material filling and planarization are performed to prepare the top electrode 5. Usually, the material of the top electrode is a metal material such as Cu, W, TaN, etc.

[0123] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A magnetic storage unit, characterized in that: include: A substrate layer, the substrate layer comprising two bottom electrodes spaced apart; A spin-orbit moment layer, disposed on the upper surface of the substrate layer, the spin-orbit moment layer at least covering the two bottom electrodes; A magnetic tunnel junction is arranged on the upper surface of the spin-orbit moment layer, and the magnetic tunnel junction at least covers the range where the two bottom electrodes are located.

2. The magnetic storage unit according to claim 1, characterized in that The edge of the magnetic tunnel junction is aligned with the edge of the spin-orbit moment layer.

3. The magnetic storage unit according to claim 1, characterized in that The magnetic tunnel junction includes a ferromagnetic layer, a barrier layer and a pinning layer. The ferromagnetic layer is located above the track layer and directly contacts the track layer.

4. The magnetic storage unit according to claim 1, characterized in that Also includes: A hard mask layer is disposed on an upper surface of the magnetic tunnel junction, and an edge of the hard mask layer is aligned with an edge of the magnetic tunnel junction.

5. The magnetic storage unit according to claim 4, characterized in that Also includes: A magnetic layer is disposed on the upper surface of the hard mask layer, and an edge of the magnetic layer is aligned with an edge of the hard mask layer.

6. The magnetic storage unit according to claim 5, characterized in that The magnetic moment direction of the magnetic layer is located in the plane of the magnetic layer or in the normal direction of the magnetic layer.

7. The magnetic storage unit according to claim 1, characterized in that The two bottom electrodes are arranged along the long axis direction of the spin-orbit moment, or the arrangement direction of the two bottom electrodes forms an angle with the long axis direction.

8. The magnetic storage unit according to claim 1, characterized in that The magnetic moment direction of the free layer of the magnetic tunnel junction is arranged along the long axis direction of the free layer, or the magnetic moment direction of the free layer of the magnetic tunnel junction is arranged along the normal direction of the free layer.

9. A method for preparing a magnetic storage unit, characterized in that: The method comprises: providing a substrate layer having two bottom electrodes; forming a spin-orbit moment layer and a magnetic tunnel junction in sequence on the substrate layer; The magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled to be no higher than the lower surface of the spin-orbit moment.

10. The method according to claim 9, characterized in that The etching of the magnetic tunnel junction and the spin-orbit moment layer once using the same mask comprises: forming a hard mask layer on the upper surface of the magnetic tunnel junction; The hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled not to be higher than the lower surface of the spin-orbit moment.

11. The method according to claim 10, characterized in that The hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, comprising: forming a magnetic layer on the upper surface of the hard mask layer; The magnetization layer, the hard mask layer, the magnetic tunnel junction and the spin-orbit moment layer are etched once using the same mask, and the etching end point is controlled not to be higher than the lower surface of the spin-orbit moment.

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