Magnetic storage structure and method of manufacturing the same

Abstract

The present invention discloses a magnetic storage structure and a manufacturing method thereof, which relates to the field of semiconductor technology and is used to solve the problems of poor process feasibility and low writing efficiency of magnetic storage devices with existing bottom pinning structures. The magnetic storage structure includes: a substrate, a magnetic tunnel junction, a spin-orbit moment layer, an etching stop layer, a dielectric structure and a special-shaped electrode; the dielectric structure wraps the sidewalls of the magnetic tunnel junction and the sidewalls of the spin-orbit moment layer, and its upper surface is higher than the upper surface of the spin-orbit moment layer; the etching stop layer does not completely cover the two ends of the spin-orbit moment layer, and together with the upper surface of the dielectric structure, forms a special-shaped through hole, and then forms a special-shaped electrode. By setting the etching stop layer, the etching end point can be accurately controlled to avoid over-etching the spin-orbit moment layer and increase the process window; the special-shaped through hole has a large top size, flexible process, small bottom size, and self-aligned with the edge of the spin-orbit moment layer, which can meet the needs of device miniaturization; the special-shaped electrode is set on the upper surface of the two ends of the spin-orbit moment layer, and the writing efficiency is high.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor technology, and in particular to a magnetic storage structure and a manufacturing method thereof. Background Art

[0002] Traditional spin-orbit moment magnetic memory (SOT-MRAM) often uses a top pinning structure, that is, the spin-orbit moment (SOT) layer is below the magnetic tunnel junction (MTJ). In order to avoid damage to the SOT layer during the manufacture of the columnar structure of the MTJ device, the etching endpoint needs to stop precisely above the SOT layer, and the process window is extremely small. Because of the extremely small etching process window, the hard mask sidewall re-deposition, etching bottom angle, and barrier layer sidewall short circuit of the MTJ are mutually restricted, making it difficult to optimize and achieve optimal performance at the same time.

[0003] To solve the above problems, those skilled in the art have proposed a SOT-MRAM with a bottom pinning structure, in which the SOT layer is set above the MTJ. In the process of manufacturing the columnar structure of the MTJ device, the requirements for the accuracy of the etching endpoint are low, and over-etching can be allowed. Therefore, the SOT-MRAM with a bottom pinning structure has greater process freedom than the traditional SOT-MRAM with a top pinning structure, and can independently optimize the sidewall redeposition, etching bottom angle and barrier layer sidewall short circuit of the MTJ. In addition, the SOT-MRAM with a bottom pinning structure has more performance advantages, such as higher tunneling magnetoresistance effect (TMR) and lower write channel resistance.

[0004] Although the bottom-pinned SOT-MRAM has many advantages in terms of process freedom and device performance, its bottleneck lies in the difficulty of manufacturing. The currently disclosed SOT-MRAM manufacturing solutions have poor process feasibility due to the narrow manufacturing window, or the SOT layer adopts a multi-layer parallel structure, resulting in low writing efficiency. Summary of the invention

[0005] To solve the above problems, the embodiments of the present disclosure provide a magnetic storage structure and a method for manufacturing the same, so as to increase the process manufacturing window of the magnetic storage structure and achieve efficient writing.

[0006] According to some embodiments, the present disclosure provides a magnetic storage structure, comprising at least:

[0007] A magnetic tunnel junction, a spin-orbit moment layer, an etching stop layer and a special-shaped electrode are sequentially stacked on a substrate, and a dielectric structure is wrapped around a side wall of the magnetic tunnel junction and a side wall of the spin-orbit moment layer;

[0008] The spin-orbit moment layer is disposed adjacent to the free layer of the magnetic tunnel junction;

[0009] The etch stop layer does not completely cover both ends of the spin-orbit moment layer, and the upper surface of the dielectric structure is higher than the upper surface of the spin-orbit moment layer, thereby forming a special-shaped through hole together with the upper surface of the dielectric structure;

[0010] The conductive material covers the irregular through hole to form an irregular electrode;

[0011] Two special-shaped electrodes are arranged on the upper surfaces of the two ends of the spin-orbit moment layer, do not contact each other and are electrically connected to the spin-orbit moment layer.

[0012] In some possible examples, the dielectric structure includes a first dielectric structure and a second dielectric structure; the first dielectric structure is disposed on a substrate, wrapping the sidewalls of the magnetic tunnel junction and the sidewalls of the spin-orbit moment layer, and the second dielectric structure is disposed on a side of the first dielectric structure away from the magnetic tunnel junction; the etch stop layer does not completely cover both ends of the spin-orbit moment layer, and the upper surface of the first dielectric structure is higher than the upper surface of the spin-orbit moment layer, thereby forming an irregular through hole together with the upper surface of the dielectric structure.

[0013] In some possible examples, an upper surface of the second dielectric structure is higher than an upper surface of the first dielectric structure.

[0014] In some possible examples, the irregular through hole is an irregular shape with a larger top dimension and a smaller bottom dimension.

[0015] In some possible examples, the contact area between the special-shaped electrode and the spin-orbit moment layer is smaller than or equal to the area of ​​the spin-orbit moment layer not covered by the etch stop layer.

[0016] In some possible examples, an isolation structure is further provided between the two special-shaped electrodes, and the isolation structure is located above the etch stop layer; the isolation structure and the etch stop layer are both made of insulating materials.

[0017] The magnetic storage structure provided by the embodiments of the present disclosure has at least the following advantages:

[0018] In the magnetic storage structure of the disclosed embodiment, an etching stop layer is arranged above the spin-orbit moment layer so that the etching end point stops accurately on the spin-orbit moment layer, thereby avoiding damage to the performance of the magnetic storage structure caused by excessive etching of the spin-orbit moment layer and ensuring a large process window; the etching stop layer is limited to not completely cover both ends of the spin-orbit moment layer, and the upper surface of the dielectric structure is higher than the upper surface of the spin-orbit moment layer, thereby forming a special-shaped through hole together with the upper surface of the dielectric structure, and the height of the protrusion of the dielectric structure avoids excessive etching of the sidewall without the etching stop area to cause a short circuit; the top size of the formed special-shaped through hole is large, easy to fill, low in series resistance, high in process flexibility, the bottom size of the special-shaped through hole is small, self-aligned with the edge of the spin-orbit moment layer, the bottom size can be not limited by the lithography resolution, fully meets the requirements of miniaturization of the magnetic storage structure, and can realize a high-density array; and the special-shaped electrodes are arranged on the upper surfaces of both ends of the spin-orbit moment layer, and the write current can be directly passed into the spin-orbit moment layer, thereby improving the utilization rate of the write current and the write efficiency.

[0019] According to some embodiments, the present disclosure provides a method for manufacturing a magnetic storage structure, the steps comprising:

[0020] A magnetic tunnel junction, a spin-orbit moment layer, an etch stop layer, a first mask and a first dielectric layer are sequentially formed on a substrate, wherein the first dielectric layer at least covers a sidewall of the magnetic tunnel junction, a sidewall of the spin-orbit moment layer and a sidewall of the first mask;

[0021] Removing part of the first dielectric layer and the first mask, leaving the upper surface of the remaining first dielectric layer higher than the upper surface of the spin-orbit moment layer, removing part of the etch stop layer to expose two ends of the spin-orbit moment layer, and forming a special-shaped through hole;

[0022] The remaining first dielectric layer forms a dielectric structure;

[0023] Special-shaped electrodes are formed. Two special-shaped electrodes are formed on both sides of the etching stop layer, do not contact each other and are electrically connected to the spin-orbit moment layer.

[0024] In some possible examples, a second mask is further formed under the first mask; forming the special-shaped through hole comprises:

[0025] Removing part of the first dielectric layer and the first mask, the first mask forms a groove above the second mask, and the upper surface of the remaining first dielectric layer on both sides of the groove is higher than the upper surface of the second mask;

[0026] A mask structure is formed in the groove, and a portion of the etching stop layer is removed based on the mask structure to expose two ends of the spin-orbit moment layer and form a special-shaped through hole.

[0027] In some possible examples, a second mask is further formed under the first mask; forming the special-shaped through hole comprises:

[0028] removing a portion of the first dielectric layer to expose the first mask, and applying microscaling to the second mask to reduce its lateral dimensions;

[0029] The first mask is removed, a mask structure is formed based on the remaining second mask, a portion of the etch stop layer is removed based on the mask structure, two ends of the spin-orbit moment layer are exposed, and a special-shaped through hole is formed.

[0030] In some possible examples, a third mask is formed under the second mask; the first mask is removed, a mask structure is formed based on the remaining second mask and third mask, part of the etch stop layer is removed based on the mask structure, exposing both ends of the spin-orbit moment layer to form a special-shaped through hole.

[0031] In some possible examples, when a mask structure is formed based on the remaining second mask and the third mask, an etching rate of the third mask is higher than an etching rate of the first dielectric layer.

[0032] In some possible examples, when a portion of the first dielectric layer and the first mask are removed, an etching rate of the first mask is higher than an etching rate of the first dielectric layer.

[0033] In some possible examples, the first dielectric layer includes a first dielectric sublayer and a second dielectric sublayer;

[0034] The first dielectric sublayer is formed on the substrate, and at least covers the sidewall of the magnetic tunnel junction, the sidewall of the spin-orbit moment layer, and the sidewall of the first mask, and the second dielectric sublayer is formed on a side of the first dielectric sublayer away from the magnetic tunnel junction;

[0035] Removing part of the first dielectric sublayer and the first mask, so that the upper surface of the remaining first dielectric sublayer is higher than the upper surface of the spin-orbit moment layer, removing part of the etching stop layer, exposing both ends of the spin-orbit moment layer, and forming a special-shaped through hole;

[0036] The remaining first dielectric sublayer constitutes a first dielectric structure, the remaining second dielectric sublayer constitutes a second dielectric structure, and the first dielectric structure and the second dielectric structure constitute a dielectric structure.

[0037] The method for manufacturing the magnetic storage structure in the embodiment of the present disclosure has at least the following advantages:

[0038] In the manufacturing method of the magnetic storage structure in the embodiment of the present disclosure, an etching stop layer is arranged above the spin-orbit moment layer so that the etching end point stops accurately on the spin-orbit moment layer, thereby avoiding damage to the performance of the magnetic storage structure caused by excessive etching of the spin-orbit moment layer and ensuring a large process window; by removing part of the first dielectric layer, the etched amount above the first dielectric layer defines the thickness of the conductive material deposited in the special-shaped through hole, and the height of the protrusion of the remaining first dielectric layer avoids short circuit caused by excessive etching of the side wall without an etching stop area; finally, the upper surface of the remaining first dielectric layer is higher than the upper surface of the spin-orbit moment layer, And by removing part of the etch stop layer to expose the two ends of the spin-orbit moment layer, a special-shaped through hole is formed. The top size of the special-shaped through hole is large, easy to fill, low in series resistance, high in process flexibility, and the bottom size of the special-shaped through hole is small, self-aligned to the edge of the spin-orbit moment layer, with less masks and simple process. The bottom size of the special-shaped through hole is not limited by the lithography resolution, which fully meets the needs of miniaturization of the magnetic storage structure and can realize a high-density array. In addition, the special-shaped electrodes are arranged on the upper surfaces of the two ends of the spin-orbit moment layer, and the write current can be directly passed into the spin-orbit moment layer, thereby improving the utilization rate of the write current and the write efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a top view of the magnetic storage structure in an embodiment of the present disclosure;

[0040] Figure 2 Schematic diagram of a device cross-section of a first magnetic storage structure along the AA′ direction in an embodiment of the present disclosure;

[0041] Figure 3 Schematic diagram of a device cross-section of a second magnetic storage structure along the AA´ direction in an embodiment of the present disclosure;

[0042] Figure 4 Schematic diagram of a device cross-section of a third magnetic storage structure along the AA´ direction in an embodiment of the present disclosure;

[0043] Figure 5 This is a schematic diagram of the structure of a magnetic tunnel junction in one embodiment of the present disclosure;

[0044] Figure 6 It is a flow chart of a method for manufacturing a magnetic storage structure in one embodiment of the present disclosure;

[0045] Figure 7 It is a schematic cross-sectional view of a device after a first dielectric layer is deposited in a manufacturing method in one embodiment of the present disclosure;

[0046] Figure 8 It is a schematic cross-sectional view of a device after depositing a first dielectric layer in another manufacturing method in one embodiment of the present disclosure;

[0047] Fig. 9It is a schematic cross-sectional view of a device after a groove is formed on a second mask in the first manufacturing method for forming a special-shaped through hole in an embodiment of the present disclosure;

[0048] Fig.10 It is a schematic cross-sectional view of a device after a special-shaped through hole is formed in the first manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0049] Fig.11 It is a schematic cross-sectional view of a device after a groove is formed above a second mask in the second manufacturing method for forming a special-shaped through hole in an embodiment of the present disclosure;

[0050] Fig.12 It is a schematic cross-sectional view of a device after a portion of the second dielectric layer is removed in the second manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0051] Fig.13 It is a schematic cross-sectional view of a device after a special-shaped through hole is formed in the second manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0052] Fig.14 It is a schematic cross-sectional view of a device after lateral shrinkage is applied to the second mask in the fourth manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0053] Fig.15 It is a schematic cross-sectional view of a device after forming a special-shaped through hole in the fourth manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0054] Fig.16 It is a schematic cross-sectional view of a device after lateral shrinkage is applied to the second mask in the fifth manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0055] Fig.17 It is a schematic cross-sectional view of a device after a special-shaped through hole is formed in the fifth manufacturing method for forming a special-shaped through hole in one embodiment of the present disclosure;

[0056] Fig.18 It is a top view of a magnetic storage structure with a trapezoidal magnetic tunnel junction cross section in one embodiment of the present disclosure.

[0057] 10-substrate; 20-magnetic tunnel junction; 21-free layer; 22-barrier layer; 23-reference layer; 24-pinned layer; 30-spin-orbit moment layer; 40-etching stop layer; 50-special-shaped electrode; 60-dielectric structure; 61-first dielectric structure; 62-second dielectric structure; 70-isolation structure; 80-conductive via; 90-first dielectric layer; 91-first dielectric sublayer; 92-second dielectric sublayer; 100-first mask; 110-second mask; 120-second dielectric layer; 130-third dielectric layer; 140-mask structure; 150-special-shaped via; 160-third mask. DETAILED DESCRIPTION

[0058] In the prior art, the bottom pinned SOT-MRAM has many advantages in terms of process freedom, device performance, etc., but its bottleneck lies in the difficulty of manufacturing. The currently disclosed SOT-MRAM manufacturing scheme has poor process feasibility due to the narrow manufacturing window, or the SOT layer adopts a multi-layer parallel structure, resulting in low writing efficiency.

[0059] Therefore, in the magnetic storage structure of the embodiment of the present disclosure, an etching stop layer is arranged above the spin-orbit moment layer so that the etching end point stops accurately on the spin-orbit moment layer, thereby avoiding damage to the performance of the magnetic storage structure caused by excessive etching of the spin-orbit moment layer, and ensuring a large process window; the etching stop layer is limited to not completely cover the two ends of the spin-orbit moment layer, and the upper surface of the dielectric structure is higher than the upper surface of the spin-orbit moment layer, so that together with the upper surface of the dielectric structure, a special-shaped through hole is formed, and the height of the protrusion of the dielectric structure avoids excessive etching of the sidewall without an etching stop area to cause a short circuit; the top size of the formed special-shaped through hole is large, easy to fill, low in series resistance, high in process flexibility, the bottom size of the special-shaped through hole is small, self-aligned with the edge of the spin-orbit moment layer, the bottom size can be free from the limitation of the lithography resolution, and the demand for miniaturization of the magnetic storage structure is fully met, and a high-density array can be realized; and the special-shaped electrodes are arranged on the upper surfaces of the two ends of the spin-orbit moment layer, and the write current can be directly passed into the spin-orbit moment layer, thereby improving the utilization rate of the write current and the write efficiency.

[0060] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present disclosure more obvious and easy to understand, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the embodiments described in the present disclosure are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present disclosure.

[0061] To facilitate description of the relative positional relationship between the components within the magnetic storage structure in the embodiment of the present disclosure, Figure 1 A top view of the magnetic storage structure in the embodiment of the present disclosure is provided, in which the direction of AA' is the direction of one of the cross sections; Figures 2 to 4 Schematic diagrams of device cross-sections along the AA' direction of three different magnetic storage structures in the embodiment of the present disclosure. Since the three different magnetic storage structures are mainly reflected in the arrangement of the medium structure and the special-shaped electrode structure, the top views thereof can all be referred to as Figure 1 As shown, the differences in the internal settings of different magnetic storage structures can be referred to Figures 2 to 4 ; Figure 1Only one top view of different magnetic storage structures is used as an example, and other possible top views are not described in detail here.

[0062] Figures 7 to 17 It is a device cross-sectional view of the magnetic storage structure after different process operation steps during the manufacturing method of the magnetic storage structure. Since the manufacturing method mainly involves changes in various components inside the magnetic storage structure, the device cross-sectional view of the magnetic storage structure is only provided as a reference.

[0063] refer to Figure 1 and Figure 2 , is a schematic diagram of a first magnetic storage structure provided by an embodiment of the present disclosure, and at least includes: a substrate 10, a magnetic tunnel junction 20, a spin-orbit moment layer 30, an etch-stop layer 40, a special-shaped electrode 50 and a dielectric structure 60. The magnetic tunnel junction 20, the spin-orbit moment layer 30, the etch-stop layer 40 and the special-shaped electrode 50 are sequentially stacked on the substrate 10 from bottom to top, and a dielectric structure 60 is also provided on the substrate 10, which wraps around the sidewalls of the magnetic tunnel junction 20 and the sidewalls of the spin-orbit moment layer 30 to protect them; the spin-orbit moment layer 30 is arranged adjacent to the free layer of the magnetic tunnel junction 20 to form a bottom-pinned magnetic storage structure; the etch-stop layer 40 does not completely cover the two ends of the spin-orbit moment layer 30, and the size of the exposed area of ​​the two ends of the spin-orbit moment layer 30 is not limited here, but the entire upper surface of the spin-orbit moment layer 30 cannot be completely exposed; and the upper surface of the dielectric structure 60 The surface of the special-shaped through hole is higher than the upper surface of the spin-orbit moment layer 30, thereby forming a special-shaped through hole (not shown in the figure) together with the upper surface of the dielectric structure 60. It can be understood that the bottom surface of the special-shaped through hole is composed of the upper surface of the spin-orbit moment layer 30 that is not completely covered by the etching stop layer 40 and the upper surface of the dielectric structure 60. The height of the protrusion of the dielectric structure 60 avoids the over-etching of the side wall without the etching stop area to cause a short circuit, thereby ensuring the electrical performance and yield of the magnetic storage structure; after the conductive material covers the special-shaped through hole, a special-shaped electrode 50 is formed; the two special-shaped electrodes 50 are arranged on the upper surfaces of the two ends of the spin-orbit moment layer 30, and the two do not contact each other and are electrically connected to the spin-orbit moment layer 30.

[0064] Continue to refer Figure 1 and Figure 2In the magnetic storage structure provided by the embodiment of the present disclosure, the substrate 10 is arranged below the magnetic tunnel junction 20 and the dielectric structure 60. Among them, the dielectric structure 60 can completely cover the remaining substrate 10 not covered by the magnetic tunnel junction 20, or can partially cover the substrate 10, and there is no limitation here. The dielectric structure 60 in direct contact with the substrate 10 at least wraps the side wall of the magnetic tunnel junction 20. The shape of the substrate 10 can be a variety of shapes such as circular, rectangular, diamond, etc., which can be selected according to actual manufacturing requirements; 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; a conductive through hole 80 is also provided in the substrate 10 to achieve electrical connection with the magnetic tunnel junction 20.

[0065] The orthographic projection shape of the magnetic tunnel junction 20 on the substrate 10 can be an ellipse, a circle, a triangle, a rhombus, etc., and its structure is as follows: Figure 5 As shown, it at least includes: a free layer 21, a barrier layer 22 and a reference layer 23, wherein the free layer 21 is close to the spin-orbit moment layer 30 and is located below the spin-orbit moment layer 30, forming a bottom pinned structure. Among them, the material of the free layer 21 and the reference layer 23 can be a ferromagnetic material, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc., or a ferrimagnetic material; the free layer 21 and the reference layer 23 can be a single layer or a composite film layer; the material of the barrier layer 22 is an insulating material, such as magnesium oxide, aluminum oxide, silicon oxide, etc. In addition, a pinning layer 24 can also be provided in the magnetic tunnel junction 20, which is located below the reference layer 23 to fix the magnetization direction of the reference layer 23.

[0066] Furthermore, a seed layer, a spacer layer, or other functional film layers (not shown in the figure) may be provided between the magnetic tunnel junction 20 and the substrate 10 to further enhance the electrical properties of the magnetic storage structure. Such film layers may be provided individually or simultaneously. For example, the seed layer has a specific crystal structure, which may improve the crystallization of the magnetic tunnel junction 20; the spacer layer, such as the coupling layer, may enhance the tunneling resistance effect. At this time, the dielectric structure 60 should also wrap the side walls of such functional film layers to protect the side walls of the magnetic storage structure, thereby avoiding bottom deposition and sidewall damage during subsequent manufacturing processes, which may damage the electrical properties of the magnetic storage structure.

[0067] In the magnetic storage structure of the embodiment of the present disclosure, the spin-orbit moment layer 30 is a material that can produce a spin-orbit moment effect, including platinum, palladium, hafnium, gold, tantalum, tungsten, iridium or an alloy thereof; or a topological insulator, including bismuth selenide (Bi x Se 1-x ), bismuth antimonide (Bi x Sb 1-x), bismuth telluride-based materials (Bi, Sb) 2Te3, etc., 0<x<1; it can also be a two-dimensional material, such as molybdenum disulfide (MoS2), tungsten ditelluride (WTe2), etc.; the spin-orbit moment 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.

[0068] The etch stop layer 40 is made of insulating material, such as magnesium oxide, or a mixture of magnesium oxide and silicon oxide, or a mixture of magnesium oxide and silicon nitride.

[0069] In the magnetic storage structure of the disclosed embodiment, the irregular through hole is an irregular shape with a large top size and a small bottom size, such as a step shape. The top cross-sectional area of ​​the irregular through hole is large, which is easy to fill with conductive materials and has high process flexibility; the bottom morphology of the irregular through hole is due to the exposure of both ends of the spin-orbit moment layer 30, and the cross-sectional area is small by self-aligning the edge of the spin-orbit moment layer 30, which facilitates the miniaturization of the magnetic storage structure.

[0070] After the special-shaped through hole is filled with a conductive material, a special-shaped electrode 50 can be formed, and the contact area between the special-shaped electrode 50 and the spin-orbit moment layer 30 is less than or equal to the area of ​​the spin-orbit moment layer 30 not covered by the etching stop layer 40, that is, the bottom cross-sectional area of ​​the special-shaped electrode 50 can be smaller than the area of ​​the upper surface exposed by the spin-orbit moment layer 30, and the remaining position can be filled with an insulating material. A preferred solution is that the contact area between the special-shaped electrode 50 and the spin-orbit moment layer 30 is equal to the area of ​​the spin-orbit moment layer 30 not covered by the etching stop layer 40, and the edge of the special-shaped electrode 50 is flush with the edge of the spin-orbit moment layer 30, so that the bottom morphology of the special-shaped electrode 50 is not limited by the resolution size of the lithography, meeting the requirements of miniaturization of the magnetic storage structure, and a high-density magnetic storage array can be manufactured.

[0071] In the magnetic storage structure of the disclosed embodiment, the two ends of the spin-orbit moment layer 30 are connected by two special-shaped electrodes 50, and the two special-shaped electrodes 50 may also be provided with an isolation structure 70 for electrical isolation. Among them, the isolation structure 70 is an insulating material, located above the etching stop layer 40, and the specific structure of the isolation structure 70 is not limited here, and any structure that can electrically isolate the two special-shaped electrodes 50 from each other can be used as the isolation structure 70. Since both the isolation structure 70 and the etching stop layer 40 are made of insulating materials, it can be ensured that there is no parallel resistance in the magnetic storage structure that shares the write current of the spin-orbit moment layer 30, and the maximum write efficiency is achieved.

[0072] refer to Figure 1 and Figure 3, is a schematic diagram of a second magnetic storage structure provided in an embodiment of the present disclosure, which is basically the same as the magnetic storage structure of the first structure, and the main difference is that: the dielectric structure 60 in the magnetic storage structure includes a first dielectric structure 61 and a second dielectric structure 62; the first dielectric structure 61 is arranged on the substrate 10, wrapping the side wall of the magnetic tunnel junction 20 and the side wall of the spin-orbit moment layer 30, and the second dielectric structure 62 is arranged on the side of the first dielectric structure 61 away from the magnetic tunnel junction 20; the etch stop layer 40 does not completely cover the two ends of the spin-orbit moment layer 30, and the upper surface of the first dielectric structure 61 is higher than the upper surface of the spin-orbit moment layer 30, and the upper surface of the second dielectric structure 62 is flush with the upper surface of the first dielectric structure 61, thereby forming a special-shaped through hole together with the upper surface of the dielectric structure 60. Among them, the first dielectric structure 61 directly protects the side walls of the magnetic tunnel junction 20 and the side walls of the spin-orbit moment layer 30, and the second dielectric structure 62 is arranged on the outside of the first dielectric structure 61, further protecting the first dielectric structure 61 and the side walls of the magnetic tunnel junction 20, avoiding sidewall redeposition and sidewall damage.

[0073] Furthermore, for Figure 3 In the magnetic storage structure shown, the first dielectric structure 61 can completely cover the remaining substrate 10 not covered by the magnetic tunnel junction 20, or can partially cover the remaining substrate 10 not covered by the magnetic tunnel junction 20; there is no specific restriction on the area of ​​the substrate 10 covered by the first dielectric structure 61. The first dielectric structure 61 in direct contact with the substrate 10 only needs to wrap the side wall of the magnetic tunnel junction 20, and the upper surface of the remaining substrate 10 can be exposed or covered by the second dielectric structure 62 outside the first dielectric structure 61.

[0074] refer to Figure 1 and Figure 4 , is a schematic diagram of a third magnetic storage structure provided in an embodiment of the present disclosure, which is basically the same as the magnetic storage structure of the second structure, and the main difference is that the etching stop layer 40 does not completely cover the two ends of the spin-orbit moment layer 30, the upper surface of the first dielectric structure 61 is higher than the upper surface of the spin-orbit moment layer 30, and the upper surface of the second dielectric structure 62 is higher than the upper surface of the first dielectric structure 61, thereby forming a special-shaped through hole together with the upper surface of the dielectric structure 60, and the formed special-shaped through hole is stepped. By setting two media with different upper surface heights, the etching end point can be better controlled, and the manufacturing window of the magnetic storage structure can be further increased.

[0075] Further, based on the second and third magnetic storage structures described above, since the first dielectric structure 61 wraps the sidewalls of the magnetic tunnel junction 20 and the sidewalls of the spin-orbit moment layer 30, the upper surface of the first dielectric structure 61 is at least flush with the upper surface of the spin-orbit moment layer 30 to wrap the sidewalls of the spin-orbit moment layer 30. When the upper surface of the first dielectric structure 61 is flush with the upper surface of the spin-orbit moment layer 30, the upper surface of the second dielectric structure 62 needs to be higher than the upper surface of the first dielectric structure 61 to form a special-shaped through hole; when the upper surface of the first dielectric structure 61 is higher than the upper surface of the spin-orbit moment layer 30, the relative position of the upper surface of the second dielectric structure 62 and the upper surface of the first dielectric structure 61 is not limited, and it is only necessary to satisfy that the upper surface of at least one of the first dielectric structure 61 or the second dielectric structure 62 is higher than the upper surface of the spin-orbit moment layer 30, and it can be designed according to actual needs. Those skilled in the art can make any selection and combination according to actual needs, which all fall within the protection scope of the present application.

[0076] In addition, other dielectric structures may be arranged outside the second dielectric structure 62, such as a third dielectric structure, a fourth dielectric structure, etc.; or, the first dielectric structure 61 and the second dielectric structure 62 may be respectively composed of different dielectric structure sub-layers. Those skilled in the art may make any selection and combination according to actual needs, and all selections and combinations do not deviate from the technical concept of the present application and fall within the protection scope of the present application.

[0077] On the other hand, the present disclosure also provides a method for manufacturing a magnetic storage structure. The flowchart of the manufacturing method is shown in Figure 6 , specifically including the following steps:

[0078] Step S10: forming a magnetic tunnel junction, a spin-orbit moment layer, an etch stop layer, a first mask and a first dielectric layer in sequence on the substrate, wherein the first dielectric layer at least covers the sidewalls of the magnetic tunnel junction, the sidewalls of the spin-orbit moment layer and the sidewalls of the first mask;

[0079] Step S20: removing a portion of the first dielectric layer and the first mask, leaving the upper surface of the remaining first dielectric layer higher than the upper surface of the spin-orbit moment layer, removing a portion of the etch-stop layer to expose both ends of the spin-orbit moment layer, and forming a special-shaped through hole;

[0080] Step S30: the remaining first dielectric layer forms a dielectric structure;

[0081] Step S40: forming special-shaped electrodes, wherein two special-shaped electrodes are formed on both sides of the etching stop layer, do not contact each other and are electrically connected to the spin-orbit moment layer.

[0082] In the above step S10, the specific steps of forming the magnetic tunnel junction, the spin-orbit moment layer, the etch stop layer, the first mask and the first dielectric layer include:

[0083] Step S101: depositing a magnetic tunnel junction film layer, a spin orbit moment film layer, an etch stop film layer, a first mask film layer and an etch mask on a substrate;

[0084] Step S102: etching the first mask film layer, the etch stop film layer, the spin-orbit moment film layer and the magnetic tunnel junction film layer using the etch mask as a mask to form a first mask, an etch stop layer, a spin-orbit moment layer and a magnetic tunnel junction;

[0085] Step S103: depositing a first dielectric layer, wherein the first dielectric layer at least covers the sidewalls of the magnetic tunnel junction, the sidewalls of the spin-orbit moment layer and the sidewalls of the first mask.

[0086] Figure 7 This is a schematic cross-sectional view of a device after the first dielectric layer is deposited in a method for manufacturing a magnetic storage structure according to an embodiment of the present disclosure. Figure 7 A cross-sectional view of the device shown, with specific descriptions of the components in the figure:

[0087] The substrate 10 is disposed below the magnetic tunnel junction 20 and the first dielectric layer 90. The first dielectric layer 90 may completely cover the remaining substrate 10 not covered by the magnetic tunnel junction 20, or may partially cover the substrate 10, and there is no limitation here. The first dielectric layer 90 directly in contact with the substrate 10 may at least wrap the sidewall of the magnetic tunnel junction 20. The shape of the substrate 10 may be circular, rectangular, diamond, or other shapes, which may be selected according to actual manufacturing requirements; the material of the substrate 10 may be a semiconductor material, such as silicon, silicon carbide, gallium nitride, aluminum nitride, or an insulating material, such as germanium; a conductive through hole 80 is also provided in the substrate 10 to realize electrical connection with the magnetic tunnel junction 20.

[0088] The orthographic projection shape of the magnetic tunnel junction 20 on the substrate 10 can be an ellipse, a circle, a trapezoid, a triangle, a rhombus, etc., and its structure is as follows: Figure 5 As shown, it at least includes: a free layer 21, a barrier layer 22 and a reference layer 23, wherein the free layer 21 is close to the spin-orbit moment layer 30 and is located below the spin-orbit moment layer 30, forming a bottom pinned structure. Among them, the material of the free layer 21 and the reference layer 23 can be a ferromagnetic material, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc., or a ferrimagnetic material; the free layer 21 and the reference layer 23 can be a single layer or a composite film layer; the material of the barrier layer 22 is an insulating material, such as magnesium oxide, aluminum oxide, silicon oxide, etc. In addition, a pinning layer 24 can also be provided in the magnetic tunnel junction 20, which is located below the reference layer 23 to fix the magnetization direction of the reference layer 23.

[0089] Furthermore, a seed layer, a spacer layer, and other functional film layers (not shown in the figure) may be provided between the magnetic tunnel junction 20 and the substrate 10 to further enhance the electrical properties of the magnetic storage structure. Such film layers may be provided individually or simultaneously. For example, the seed layer has a specific crystal structure, which may improve the crystallization of the magnetic tunnel junction 20; the spacer layer, such as the coupling layer, may enhance the tunneling resistance effect. At this time, the first dielectric layer 90 should also wrap the side walls of such functional film layers to protect the side walls of the magnetic storage structure, to avoid bottom deposition and sidewall damage during subsequent manufacturing processes, and to damage the electrical properties of the magnetic storage structure.

[0090] In the manufacturing method of the magnetic storage structure of the embodiment of the present disclosure, the spin-orbit moment layer 30 is a material that can produce a spin-orbit moment effect, including platinum, palladium, hafnium, gold, tantalum, tungsten, iridium or an alloy thereof; or a topological insulator, including bismuth selenide (Bi x Se 1-x ), bismuth antimonide (Bi x Sb 1-x ), bismuth telluride-based materials (Bi, Sb) 2Te3, etc., 0<x<1; it can also be a two-dimensional material, such as molybdenum disulfide (MoS2), tungsten ditelluride (WTe2), etc.; the spin-orbit moment 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.

[0091] The material of the etch stop layer 40 is an insulating material, such as magnesium oxide, or a mixture of magnesium oxide and silicon oxide, or a mixture of magnesium oxide and silicon nitride, etc. The setting of the etch stop layer 40 enables the etching end point to stop accurately on the spin-orbit moment layer 30, avoiding damage to the magnetic storage structure performance caused by excessive etching of the spin-orbit moment layer 30, and ensuring a large process window.

[0092] The deposition method of the first dielectric layer 90 is chemical vapor deposition, physical vapor deposition, etc. By depositing the first dielectric layer 90, the bottom and side walls of the magnetic tunnel junction 20 are protected to prevent the generation of bottom deposition, sidewall redeposition and other substances, and to avoid short circuit of the magnetic storage structure and damage to the electrical performance. The first dielectric layer 90 can also be deposited on the top of the first mask 100 simultaneously. The material of the first dielectric layer 90 is selected from insulating materials, such as silicon nitride (SiN) material. In addition, the first dielectric layer 90 can also be composed of multiple dielectric sublayers of the same material. During manufacturing, multiple dielectric sublayers of the same material can be deposited step by step to form the first dielectric layer 90 together, or can be deposited simultaneously to form the first dielectric layer 90. Those skilled in the art can make a choice according to their needs.

[0093] In the manufacturing method of the magnetic storage structure of this embodiment, the structure of the first mask 100 can be a single-layer mask, or a multi-layer mask or a composite mask; the material of the first mask 100 is selected to have a high etching selectivity ratio with the first dielectric layer 90, so as to facilitate the subsequent process steps, specifically: when the target is etched with the first mask 100, the etching rate of the first mask 100 needs to be higher than the etching rate of the first dielectric layer 90, and the material can be selected, such as spin-on carbon (SOC) or ruthenium (Ru) element or silicon oxide (SiO), etc.

[0094] In addition, the etching mask may be removed or retained before depositing the first dielectric layer 90 , and the deposited first dielectric layer 90 may cover the etching mask.

[0095] With respect to the above step S10, the present disclosure also provides another method for manufacturing a magnetic storage structure. The schematic diagram of the device cross section after the first dielectric layer 90 is deposited in the manufacturing method can be found in FIG. Figure 8 , the difference between this manufacturing method and the aforementioned manufacturing method is that:

[0096] First, the structure of the deposited first dielectric layer 90 is different, specifically: in the manufacturing method, the deposited first dielectric layer 90 includes a first dielectric sublayer 91 and a second dielectric sublayer 92; wherein the first dielectric sublayer 91 is formed on the substrate 10, at least wrapping the sidewall of the magnetic tunnel junction 20, the sidewall of the spin-orbit moment layer 30 and the sidewall of the first mask 100, and the second dielectric sublayer 92 is formed on the side of the first dielectric sublayer 91 away from the magnetic tunnel junction 20; the first dielectric sublayer 91 may only cover the two sides of the second dielectric sublayer 92, or may wrap around the outer periphery of the second dielectric sublayer 92;

[0097] Secondly, the first dielectric sublayer 91 and the second dielectric sublayer 92 are made of different materials: the material of the first dielectric sublayer 91 is an insulating material, such as silicon nitride (SiN); the second dielectric sublayer 92 is made of a material having a high etching selectivity with the first dielectric layer 90, so as to facilitate subsequent process steps, specifically: when the first dielectric sublayer 91 is the etching target, the etching rate of the second dielectric sublayer 92 needs to be lower than that of the first dielectric sublayer 91, such as silicon oxide (SiO); the first mask 100 is made of a material having a high etching selectivity with the first dielectric sublayer 91, so as to facilitate subsequent process steps, specifically: when the first mask 100 is the etching target, the etching rate of the first mask 100 needs to be higher than that of the first dielectric sublayer 91, and the material can be selected, such as spin-on carbon (SOC) or ruthenium (Ru) element or silicon oxide (SiO).

[0098] In addition, in the manufacturing method of the magnetic storage structure of the present embodiment, the manufacturing method of forming the substrate 10, the magnetic tunnel junction 20, the spin-track moment layer 30, the etch stop layer 40 and the first mask 100 is the same as that of the present embodiment. Figure 7 The manufacturing method of the magnetic storage structure shown is basically the same and will not be described in detail here.

[0099] Furthermore, other dielectric sublayers may be arranged outside the second dielectric sublayer 92, such as a third dielectric sublayer, a fourth dielectric sublayer, etc.; or, the first dielectric sublayer 91 and the second dielectric sublayer 92 may be respectively composed of different dielectric sublayers, and the selection of their materials needs to meet the etching selectivity required by the above-mentioned manufacturing method. On this basis, those skilled in the art may make any selection and combination according to actual needs, and all selections and combinations do not deviate from the technical concept of the present application and fall within the protection scope of the present application.

[0100] Regarding the special-shaped through hole in step S20, the embodiment of the present disclosure provides at least the following manufacturing methods, which will be described in detail below with reference to the accompanying drawings:

[0101] Combination Figure 7 , Fig. 9 and Fig.10 , providing a method for manufacturing a first special-shaped through hole in a magnetic storage structure, wherein a second mask 110 is formed under a first mask 100; a portion of the first dielectric layer 90 and the first mask 100 is removed to expose the top of the first mask 100, and then the remaining first mask 100 is removed to form a groove above the second mask 110.

[0102] Among them, when etching the remaining first mask 100, since the etching rate of the first mask 100 is higher than the etching rate of the first dielectric layer 90, after the first mask 100 is etched, the upper surface of the remaining first dielectric layer 90 on both sides of the groove is higher than the upper surface of the second mask 110, so as to ensure that the special-shaped through hole can be formed subsequently.

[0103] Continue reading Fig.10, depositing a second dielectric layer 120 and a third dielectric layer 130 to fill the above-mentioned groove, removing the second dielectric layer 120 on both sides of the first dielectric layer 90, and leaving a gap on both sides of the first dielectric layer 90, the gap can define the bottom morphology of the special-shaped through hole; continuing to etch downward with the remaining second dielectric layer 120 and the third dielectric layer 130 to transfer the pattern to the second mask 110 to form a mask structure 140, when etching the second mask 110, the etching rate of the first dielectric layer 90 is lower than the etching rate of the second mask 110, and the first dielectric layer 90 is also synchronously etched. Etching, the etched amount above the first dielectric layer 90 defines the thickness of the conductive material deposited in the irregular through hole 150, and the height of the remaining protrusion of the first dielectric layer 90 avoids the short circuit caused by excessive etching of the side wall without an etching stop area, and finally the upper surface of the remaining first dielectric layer 90 is higher than the upper surface of the spin-orbit moment layer 30; the mask structure 140 is used to remove part of the etching stop layer 40 to expose the two ends of the spin-orbit moment layer 30, and together with the top of the remaining first dielectric layer 90, form the irregular through hole 150, and the top size of the irregular through hole 150 is large and the bottom size is small.

[0104] Among them, the material selection of the second mask 110: when the second mask 110 is the etching target, the material whose etching rate is equal to or higher than that of the first dielectric layer 90, such as silicon nitride (SIN); the material selection of the second dielectric layer 120: when the second dielectric layer 120 is the etching target, the material whose etching rate is higher than that of the first dielectric layer 90, such as silicon oxide (SIO); the material selection of the third dielectric layer 130: when the etching stop layer 40 is the etching target, the material whose etching rate is lower than that of the etching stop layer 40, such as spin-on carbon (SOC) and the like; the material selection of the etching stop layer 40: when the etching target is the second mask 110, the material whose etching rate is lower than that of the second mask 110, such as silicon nitride (SIN) is selected as the material of the second mask 110, then the material of the etching stop layer 40 needs to select magnesium oxide or magnesium oxide / silicon oxide composite material with relatively low etching rate.

[0105] Combination Figure 8 , Fig.11 , Fig.12 and Fig.13 , a second method for manufacturing the special-shaped through hole 150 in the magnetic storage structure is provided, which is mainly different from the first method for manufacturing the special-shaped through hole 150 in that:

[0106] First, compare Figure 7 and Figure 8 , the structure of the first dielectric layer 90 formed by the magnetic storage structure in this embodiment is different, that is, the first dielectric layer 90 includes a first dielectric sublayer 91 and a second dielectric sublayer 92; the structural difference and material difference of this part have been described in detail in the previous step S10, and will not be repeated here;

[0107] Secondly, the steps for forming the special-shaped through hole 150 are different, specifically:

[0108] At least a portion of the first dielectric sub-layer 91 and the first mask 100 is removed to expose the top of the first mask 100 , and then the remaining first mask 100 is removed to form a groove above the second mask 110 .

[0109] Among them, when removing the remaining first mask 100, since the etching rate of the first mask 100 is higher than the etching rate of the first dielectric sublayer 91 and the second dielectric sublayer 92, after the first mask 100 is etched, the upper surface of the remaining first dielectric layer 90 on both sides of the groove is higher than the upper surface of the second mask 110, so as to ensure that the special-shaped through hole 150 can be formed subsequently.

[0110] Continue reading Fig.12 , deposit the second dielectric layer 120 and the third dielectric layer 130 to fill the above grooves, remove the second dielectric layer 120 on both sides of the first dielectric sublayer 91, and leave a gap on both sides of the first dielectric layer 90. At this time, since the etching rates of the second dielectric sublayer 92 and the second dielectric layer 120 are both greater than the first dielectric sublayer 91, the upper surface of the remaining first dielectric sublayer 91 is higher than the upper surface of the second dielectric sublayer 92; continue to etch downward with the remaining second dielectric layer 120 and the third dielectric layer 130 to transfer the pattern to The second mask 110 forms a mask structure 140. When etching the second mask 110, the first dielectric sublayer 91 is also synchronously etched, and the etching rate of the second dielectric sublayer 92 is lower than the etching rate of the first dielectric sublayer 91, so the upper surface of the second dielectric sublayer 92 is higher than the upper surface of the first dielectric sublayer 91; the mask structure 140 is used to remove part of the etching stop layer 40 to expose the two ends of the spin-orbit moment layer 30, and together with the top of the remaining first dielectric layer 90, a stepped special-shaped through hole 150 is formed.

[0111] The material of the second dielectric layer 120 is selected as follows: when the second dielectric layer 120 is used as the etching target, the material whose etching rate is higher than that of the first dielectric sublayer 91 is selected, such as silicon oxide (SiO). In addition, the materials of the substrate 10, the magnetic tunnel junction 20, the spin-orbit moment layer 30, the etching stop layer 40, the first mask 100, the second mask 110 and the third dielectric layer 130 in the manufacturing method of the magnetic storage structure are basically the same as those in the first manufacturing method of the special-shaped through hole, and are not described in detail here.

[0112] In the manufacturing method of the second special-shaped through hole 150 in the magnetic storage structure of this embodiment, by designing two dielectric sublayers and having a high etching selectivity ratio between the two dielectric sublayers, the etching endpoint can be better controlled and the process window of the magnetic storage structure can be increased.

[0113] refer to Figure 3 , Figure 8 and Fig.11 The embodiment of the present disclosure provides a third method for manufacturing a special-shaped through hole 150 in a magnetic storage structure. The difference from the second method for manufacturing a special-shaped through hole is mainly that: according to the etching selectivity data of each component in the magnetic storage structure, by setting the deposition thickness and etching parameters (such as etching angle, etching time, etc.) of each film layer, the upper surface of the remaining second dielectric sublayer 92 can be flush with the upper surface of the first dielectric sublayer 91, and the mask structure 140 is used to remove part of the etching stop layer 40 to expose the two ends of the spin-orbit moment layer 30, and together with the top of the remaining first dielectric layer 90, a special-shaped through hole 150 is formed, and a conductive material is filled in the special-shaped through hole 150 to form a special-shaped electrode. In the magnetic storage structure finally formed by using the third method for manufacturing a special-shaped through hole, Figure 3 The illustrated special-shaped electrode 50 is formed by using the third method for manufacturing special-shaped through holes disclosed in the present invention.

[0114] In addition, the materials of the substrate 10, the magnetic tunnel junction 20, the spin-orbit moment layer 30, the etch stop layer 40, the first dielectric sublayer 91, the second dielectric sublayer 92, the first mask 100, the second mask 110, the second dielectric layer 120 and the third dielectric layer 130 in the manufacturing method of the magnetic storage structure are basically the same as those in the second method for manufacturing the special-shaped through hole, and will not be repeated here.

[0115] In the above three manufacturing methods for forming the irregular through hole 150 in the magnetic storage structure, a groove is formed in the first dielectric layer 90, and the high etching selectivity between the first mask 100 and the first dielectric layer 90 is used to define the morphology of the irregular through hole 150; and the etching amount above the first dielectric layer 90 determines the thickness of the conductive material deposited subsequently; the top size of the irregular through hole 150 is large, which is easy to fill with conductive materials, has high process flexibility, low series resistance, small bottom size, and is self-aligned with the edge of the spin-orbit moment layer 30, which can be used for the manufacture of miniaturized devices; by utilizing the etching selectivity between the etching stop layer 40 and the second mask 110, the etching is accurately stopped above the etching stop layer 40, thereby ensuring the process window of the irregular through hole 150 and avoiding damage to the spin-orbit moment layer 30 and the free layer in the magnetic tunnel junction 20 below due to excessive etching.

[0116] refer to Figure 8 , Fig.14 , Fig.15The present disclosure provides a fourth method for manufacturing a special-shaped through hole 150 in a magnetic storage structure, which is as follows: a second mask 110 is formed below the first mask 100; a portion of the first dielectric layer 90 is removed until the first mask 100 is exposed, and the second mask 110 is miniaturized to reduce its lateral size; the first mask 100 is removed, and the first dielectric layer 90 is etched based on the miniaturized second mask 110; the remaining second mask 110 forms a mask structure 140, and a portion of the etch stop layer 40 is removed based on the mask structure 140; a portion of the etch stop layer 40 is removed to expose both ends of the spin-orbit moment layer 30, and together with the first dielectric layer 90, a special-shaped through hole 150 is formed.

[0117] When etching the first dielectric layer 90 based on the miniaturized second mask 110, part of the second dielectric sublayer 92 is removed because the etching rate of the second dielectric sublayer 92 is higher than that of the second mask 110. The etching amount of the second dielectric sublayer 92 determines the thickness of the conductive material filled in the subsequently formed irregular through hole. When removing part of the etching stop layer 40 based on the mask structure 140, the etching rate of the first dielectric sublayer 91 is similar to that of the second mask 110, so the first dielectric sublayer 91 and the second mask 110 are also partially consumed until part of the etching stop layer 40 is removed, exposing both ends of the spin-orbit moment layer 30, and forming the irregular through hole 150 together with the top of the first dielectric layer 90. The top size of the irregular through hole 150 is large and the bottom size is small. During the etching process, the groove effect of argon physical etching can be used to offset the chamfer produced by isotropic corrosion during the miniaturization of the second mask 110, so that the etching can be reliably stopped on the etching stop layer 40, avoiding unnecessary over-etching.

[0118] In addition, the materials of the substrate 10, the magnetic tunnel junction 20, the spin-orbit moment layer 30, the etch stop layer 40, the first dielectric sublayer 91, the second dielectric sublayer 92, the first mask 100 and the second mask 110 in the manufacturing method of the magnetic storage structure are basically the same as those in the second method for manufacturing the special-shaped through hole, and will not be repeated here.

[0119] In order to better control the etching endpoint and obtain the special-shaped through hole 150 with a larger process window, the fourth manufacturing method of the special-shaped through hole 150 of the magnetic storage structure is further improved. Figure 8 , Fig.16 , Fig.17A fifth manufacturing method for the irregular through hole 150 is provided, which differs from the fourth manufacturing method in that a third mask 160 is further formed under the second mask 110. Referring to the steps of the fourth manufacturing method, after removing the first mask 100, a mask structure 140 is formed based on the remaining second mask 110 and third mask 160. Based on the mask structure 140, part of the etch stop layer 40 is removed to expose both ends of the spin-orbit moment layer 30, thereby forming a stepped irregular through hole 150.

[0120] For details, see Figure 16-Figure 17 , remove part of the first dielectric layer 90 until the first mask 100 is exposed, and apply miniaturization to the second mask 110 to reduce its lateral size; after removing the first mask 100, etch the first dielectric layer 90 based on the miniaturized second mask 110; continue to etch the third mask 160 with the remaining second mask 110 to form a mask structure 140, and expose the two ends of the spin-orbit moment layer 30 based on the mask structure 140. Since the etching rate of the third mask 160 is higher than the etching rate of the first dielectric sub-layer 91, the upper surface of the first dielectric sub-layer 91 is higher than the upper surface of the etching stop layer 40; remove part of the etching stop layer 40 based on the mask structure 140, expose the two ends of the spin-orbit moment layer 30, and form a stepped special-shaped through hole 150 together with the top of the first dielectric layer 90.

[0121] Among them, the third mask 160 is selected from a material whose etching rate is higher than that of the first dielectric sublayer 91 when the third mask 160 is used as the etching target, such as silicon oxide (SiO). In addition, the materials of the substrate 10, the magnetic tunnel junction 20, the spin-orbit moment layer 30, the etching stop layer 40, the first dielectric sublayer 91, the second dielectric sublayer 92, the first mask 100 and the second mask 110 in the manufacturing method of the magnetic storage structure are basically the same as those in the second method for manufacturing the special-shaped through hole, and are not described in detail here.

[0122] In the fourth and fifth methods for making the irregular through hole 150 in the above-mentioned embodiments, the second mask 110 is laterally miniaturized by using a lateral etching process, and the etch stop layer 40 is etched by the miniaturized second mask 110 until both ends of the spin-orbit moment layer 30 are exposed, thereby defining the shape of the bottom of the irregular through hole 150; and the high etching selectivity between the first mask 100 and the first dielectric layer 90 is used to define the morphology of the irregular through hole 150; the amount of etching above the first dielectric layer 90 determines the amount of conductive film subsequently deposited. Material thickness; the top size of the special-shaped through hole 150 is large, which is easy to fill with conductive materials, has high process flexibility, low series resistance, small bottom size, and self-aligned with the edge of the spin-orbit moment layer 30, and can be used for the manufacture of miniaturized devices; by utilizing the etching selectivity between the etch stop layer 40 and the second mask 110, the etching is accurately stopped above the etch stop layer 40, thereby ensuring the process window of the special-shaped through hole 150 and avoiding damage to the spin-orbit moment layer 30 and the free layer in the magnetic tunnel junction 20 below due to excessive etching.

[0123] The above five methods are only specific examples for obtaining the special-shaped through hole 150 in the embodiment of the present disclosure, and are not limited to using only these five methods to obtain the special-shaped through hole 150 structure in the magnetic storage structure of the present disclosure. Those skilled in the art can flexibly adjust the above steps according to actual needs, such as changing the order of depositing film layers, changing the order of etching, etc., or appropriately adding or deleting some steps on the basis of the above methods, which do not deviate from the technical concept of the present application and fall within the protection scope of the present application.

[0124] After forming the irregular through hole 150 based on the above method, refer to Figure 2-Figure 4 Finally, the remaining first dielectric layer 90 forms a dielectric structure 60, and the upper surface of the dielectric structure 60 is higher than the upper surface of the spin-orbit moment layer 30. It can be understood that the dielectric structure 60 can be an integral structure, such as Figure 2 The structure shown in FIG. 1 has an upper surface higher than the upper surface of the spin-orbit moment layer 30; the dielectric structure 60 may also be composed of several parts, such as Figure 3 and Figure 4 In the structure shown, when depositing the first dielectric layer 90, two dielectric sublayers are deposited, including a first dielectric sublayer 91 and a second dielectric sublayer 92. After the aforementioned process steps S10-S20, the remaining first dielectric sublayer 91 constitutes the first dielectric structure 61, and the remaining second dielectric sublayer 92 constitutes the second dielectric structure 62.

[0125] In addition, other dielectric structures may be arranged outside the second dielectric structure 62, such as a third dielectric structure, a fourth dielectric structure, etc.; or, the first dielectric structure 61 and the second dielectric structure 62 may be respectively composed of different dielectric structure sub-layers. Those skilled in the art may make any selection and combination according to actual needs, and all selections and combinations do not deviate from the technical concept of the present application and fall within the protection scope of the present application.

[0126] Continue to refer Figure 2-Figure 4 After forming the special-shaped through hole 150 according to the above steps, a conductive material is filled in the special-shaped through hole 150 to form a special-shaped electrode 50. The two special-shaped electrodes 50 are arranged on the upper surface of the two ends of the spin-orbit moment layer 30. The two electrodes do not contact each other and are electrically connected to the spin-orbit moment layer 30.

[0127] Among them, after filling the conductive material in the special-shaped through hole 150, it is necessary to remove the conductive material between the two special-shaped through holes 150 so that there is no direct electrical contact between the two special-shaped electrodes 50. For example, the conductive mask that may be used in the mask structure 140 needs to be removed; or, a flattening process is used to remove the conductive material connected between the two special-shaped through holes 150 to ensure that the write current is only written into the magnetic tunnel junction 20 through the spin-track moment layer 30, thereby improving the write efficiency.

[0128] In some other possible magnetic storage structures, an isolation structure 70 is further provided between the two special-shaped electrodes 50, and is located above the etching stop layer 40. The specific structure of the isolation structure 70 is not limited here, and any structure that can separate the two special-shaped electrodes 50 from each other can be used as the isolation structure 70, and the isolation structure 70 can be formed by the mask structure 140, and the mask structure 140 needs to be insulated, or the isolation structure 70 can be formed separately after removing the mask structure 140; the isolation structure 70 uses an insulating material to ensure that there is no parallel resistance that shares the write current of the spin-orbit moment layer 30 in the magnetic storage structure, so as to ensure the maximum write efficiency.

[0129] Further, the contact area between the shaped electrode 50 and the spin-orbit moment layer 30 is less than or equal to the area of ​​the spin-orbit moment layer 30 not covered by the etching stop layer 40, that is, the bottom cross-sectional area of ​​the shaped electrode 50 can be smaller than the area of ​​the upper surface exposed by the spin-orbit moment layer 30, and the remaining position can be filled with insulating material. A preferred solution is that the contact area between the shaped electrode 50 and the spin-orbit moment layer 30 is equal to the area of ​​the spin-orbit moment layer 30 not covered by the etching stop layer 40, and the edge of the shaped electrode 50 is flush with the edge of the spin-orbit moment layer 30, so that the bottom morphology of the shaped electrode 50 is not limited by the resolution size of the lithography, meeting the requirements of miniaturization of the magnetic storage structure, and a high-density magnetic storage array can be manufactured.

[0130] In addition, in the manufacturing method provided by the embodiment of the present disclosure, the shaped electrode 50 is generated based on the two ends of the spin-orbit moment layer 30 that are not completely covered by the etching stop layer 40 and the upper surface of the dielectric structure 60. Among them, since the dielectric structure 60 is wrapped around the side wall of the magnetic tunnel junction 20, the shape of the upper surface of the dielectric structure 60 depends on the shape of the magnetic tunnel junction 20, and since the two side walls on the opposite side of the shaped electrode 50 are self-aligned at the two ends of the upper surface of the spin-orbit moment layer 30, the shape of the two side walls on the opposite side of the shaped electrode 50 depends on the shape of the spin-orbit moment layer 30. In summary, when the shape of the magnetic tunnel junction 20 and the spin-orbit moment layer 30 above it changes, the shape of the shaped electrode 50 also changes accordingly. Therefore, based on the manufacturing method provided by the embodiment of the present disclosure, those skilled in the art can change the shape of the shaped electrode 50 by designing the shape of the magnetic tunnel junction 20 to realize a magnetic storage structure with a specific function. The cross-sectional shape of the magnetic tunnel junction 20 can be a triangle, a trapezoid, a rectangle, a rhombus, etc.

[0131] refer to Fig.18 , a top view of a magnetic storage structure in which the cross section of a magnetic tunnel junction 20 is a trapezoid. In the magnetic storage structure, the cross section of the magnetic tunnel junction 20 is designed to be a trapezoid, and the magnetic storage structure is manufactured by the aforementioned manufacturing method, and the specific manufacturing method is not repeated here. Among them, the cross sections of the dielectric structure 60 wrapped around the side wall of the magnetic tunnel junction 20 and the spin-orbit moment layer 30 above the magnetic tunnel junction 20 are also trapezoidal, and the two side edges on the opposite sides of the special-shaped electrode 50 are self-aligned to the edge of the spin-orbit moment layer 30, presenting a morphology consistent with the edge of the spin-orbit moment layer 30. When the write current I is passed into the spin-orbit moment layer 30 along the direction shown in the figure, a curved charge flow as pointed by the arrow in the figure is formed in the spin-orbit moment layer 30, and then an uneven spin current is generated in the spin-orbit moment layer 30, thereby flipping the magnetic direction of the free layer in the magnetic tunnel junction 20, and realizing the field-free flipping of the magnetic storage structure with perpendicular magnetic anisotropy. Among them, the write current can also be passed along the direction corresponding to the spin-orbit moment layer 30. Fig.18 The current is written in the opposite direction as shown in FIG. , thereby generating a spin-orbit moment layer 30 with the same Fig.18 The charge flow in the direction opposite to the bent charge flow shown in is not limited to this.

[0132] The above is only a magnetic storage structure that can realize perpendicular magnetic anisotropy provided in the embodiments of the present disclosure. The deformation or adjustment made by the technicians in this field according to the actual needs, such as selecting a magnetic tunnel junction 20 of other shapes, or replacing several components therein, such as changing the dielectric structure 60 to other structures that support the formation of the special-shaped electrode 50, does not deviate from the technical concept of the present application. The selection and arbitrary combination of the several other methods listed above by the technicians in this field according to the actual needs do not deviate from the technical concept of the present application and fall within the protection scope of the present application.

[0133] In this specification, each embodiment or implementation is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referenced to each other. The description of reference terms such as "one implementation", "some implementations", "illustrative implementations", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the implementation or example are included in at least one implementation or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same implementation or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more implementations or examples in a suitable manner.

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A magnetic storage structure, characterized in that: At least: A magnetic tunnel junction, a spin-orbit moment layer, an etching stop layer and a special-shaped electrode are sequentially stacked on a substrate, and a dielectric structure is wrapped around the sidewalls of the magnetic tunnel junction and the sidewalls of the spin-orbit moment layer; The spin-orbit moment layer is disposed adjacent to the free layer of the magnetic tunnel junction; The etch stop layer does not completely cover both ends of the spin-orbit moment layer, and the upper surface of the dielectric structure is higher than the upper surface of the spin-orbit moment layer, thereby forming a special-shaped through hole together with the upper surface of the dielectric structure; The conductive material covers the special-shaped through hole to form the special-shaped electrode; The two special-shaped electrodes are arranged on the upper surfaces of the two ends of the spin-orbit moment layer, do not contact each other and are electrically connected to the spin-orbit moment layer.

2. The magnetic storage structure according to claim 1, characterized in that: The dielectric structure includes a first dielectric structure and a second dielectric structure; The first dielectric structure is disposed on the substrate, wrapping the sidewall of the magnetic tunnel junction and the sidewall of the spin-orbit moment layer, and the second dielectric structure is disposed on a side of the first dielectric structure away from the magnetic tunnel junction; The etch stop layer does not completely cover both ends of the spin-track moment layer, and the upper surface of the first dielectric structure is higher than the upper surface of the spin-track moment layer, thereby forming a special-shaped through hole together with the upper surface of the dielectric structure.

3. The magnetic storage structure according to claim 2, characterized in that: The upper surface of the second dielectric structure is higher than the upper surface of the first dielectric structure.

4. The magnetic storage structure according to any one of claims 1 to 3, characterized in that: The special-shaped through hole is a special-shaped shape with a large top size and a small bottom size.

5. The magnetic storage structure according to any one of claims 1 to 3, characterized in that: A contact area between the special-shaped electrode and the spin-orbit moment layer is smaller than or equal to an area of ​​the spin-orbit moment layer not covered by the etch-stop layer.

6. The magnetic storage structure according to any one of claims 1 to 3, characterized in that: An isolation structure is also provided between the two special-shaped electrodes, and the isolation structure is located above the etching stop layer; The isolation structure and the etching stop layer are both made of insulating materials.

7. A method for manufacturing a magnetic storage structure, characterized in that: The steps include: A magnetic tunnel junction, a spin-orbit moment layer, an etch stop layer, a first mask and a first dielectric layer are sequentially formed on a substrate, wherein the first dielectric layer at least wraps the sidewalls of the magnetic tunnel junction, the sidewalls of the spin-orbit moment layer and the sidewalls of the first mask; Removing part of the first dielectric layer and the first mask, so that the upper surface of the remaining first dielectric layer is higher than the upper surface of the spin-orbit moment layer, and removing part of the etch stop layer to expose two ends of the spin-orbit moment layer to form a special-shaped through hole; The remaining first dielectric layer forms a dielectric structure; Special-shaped electrodes are formed, wherein two special-shaped electrodes are formed on both sides of the etching stop layer, do not contact each other and are electrically connected to the spin-orbit moment layer.

8. The manufacturing method according to claim 7, characterized in that: A second mask is also formed below the first mask; The steps of forming the special-shaped through hole include: removing a portion of the first dielectric layer and the first mask, wherein the first mask forms a groove above the second mask, and the upper surfaces of the remaining first dielectric layer on both sides of the groove are higher than the upper surface of the second mask; A mask structure is formed in the groove, and a portion of the etch stop layer is removed based on the mask structure to expose two ends of the spin-orbit moment layer to form a special-shaped through hole.

9. The manufacturing method according to claim 7, characterized in that: A second mask is also formed below the first mask; The steps of forming the special-shaped through hole include: removing a portion of the first dielectric layer to expose the first mask, and applying microscaling to the second mask to reduce its lateral dimensions; The first mask is removed, a mask structure is formed based on the remaining second mask, a portion of the etch stop layer is removed based on the mask structure, two ends of the spin-orbit moment layer are exposed, and a special-shaped through hole is formed.

10. The manufacturing method according to claim 9, characterized in that: A third mask is also formed below the second mask; The first mask is removed, a mask structure is formed based on the remaining second mask and the third mask, a portion of the etch stop layer is removed based on the mask structure, two ends of the spin-orbit moment layer are exposed, and a special-shaped through hole is formed.

11. The manufacturing method according to claim 10, characterized in that: When a mask structure is formed based on the remaining second mask and the third mask, an etching rate of the third mask is higher than an etching rate of the first dielectric layer.

12. The manufacturing method according to any one of claims 7 to 11, characterized in that: When the first dielectric layer and the first mask are partially removed, an etching rate of the first mask is higher than an etching rate of the first dielectric layer.

13. The manufacturing method according to any one of claims 7 to 11, characterized in that: The first dielectric layer includes a first dielectric sublayer and a second dielectric sublayer; The first dielectric sublayer is formed on the substrate, and at least wraps the sidewall of the magnetic tunnel junction, the sidewall of the spin-orbit moment layer, and the sidewall of the first mask; the second dielectric sublayer is formed on a side of the first dielectric sublayer away from the magnetic tunnel junction; Removing part of the first dielectric sublayer and the first mask, leaving the upper surface of the remaining first dielectric sublayer higher than the upper surface of the spin-orbit moment layer, removing part of the etch stop layer, exposing two ends of the spin-orbit moment layer, and forming a special-shaped through hole; The remaining first dielectric sublayer constitutes a first dielectric structure, the remaining second dielectric sublayer constitutes a second dielectric structure, and the first dielectric structure and the second dielectric structure constitute the dielectric structure.

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