Semiconductor memory structure and method of manufacturing the same

Abstract

The present application provides a semiconductor storage structure and a manufacturing method thereof, relating to the field of semiconductor technology, and is used to solve the problems of increased process steps and costs caused by additionally setting a magnetic shielding layer to achieve the electromagnetic shielding function in the prior art. The semiconductor storage structure includes: a data storage structure and an external shielding structure disposed on the outer periphery of the data storage structure; the data storage structure includes at least one magnetic tunnel junction; the external shielding structure is formed by horizontally connecting an external shielding layer and at least one first conductive structure to form a closed figure, and there is a potential difference between both ends of the first conductive structure; both the magnetic tunnel junction and the external shielding layer are obtained by synchronous etching based on a magnetic tunnel junction film stack. By setting the external shielding structure and forming an equipotential body, the electromagnetic shielding of the data storage structure is effectively achieved; the magnetic tunnel junction and the external shielding layer are obtained by synchronous etching based on the magnetic tunnel junction film stack, without adding additional process steps, effectively reducing the manufacturing cost.

Description

Technical Field

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

[0002] The basic storage unit of a magnetic random access memory (MRAM) is a magnetic tunnel junction (MTJ). The core structure of the MTJ is a sandwich structure of a reference layer / barrier layer / free layer, where the magnetization direction of the reference layer remains unchanged, and the magnetization direction of the free layer can be changed by an external excitation to achieve data writing. When the magnetization direction of the free layer is parallel or antiparallel to that of the reference layer, the MTJ is in a low-resistance state or a high-resistance state respectively, and the two resistance states can represent binary data "0" and "1" respectively.

[0003] During the read and write processes of the magnetic memory, the electromagnetic fields in the external environment (such as power supplies, radio waves, etc.) and the electromagnetic fields generated during the read and write of adjacent devices will cause certain interference to the storage devices. Especially when the density of the storage devices increases, the distance between the storage devices becomes shorter, or when the same adjacent storage device is repeatedly read and written at a high frequency, this type of electromagnetic influence will be aggravated, resulting in an increase in the read and write error rate of the storage devices.

[0004] To solve the above problems, the prior art usually coats an additional magnetic shielding layer outside the magnetic tunnel junction or the memory chip to reduce the electromagnetic interference from adjacent devices and external electromagnetic interference and reduce the read and write error rate. However, this method requires adding a preparation step for the magnetic shielding layer outside the manufacturing process of the magnetic memory, increasing additional processes and manufacturing costs. Summary of the Invention

[0005] To solve the above problems, embodiments of this application provide a semiconductor memory structure and a manufacturing method thereof, which can simplify the manufacturing process and reduce the manufacturing cost while achieving electromagnetic shielding.

[0006] According to some embodiments, this application provides a semiconductor memory structure, including at least:

[0007] A data storage structure and an external shielding structure disposed on the outer periphery of the data storage structure; the data storage structure includes at least one magnetic tunnel junction; the external shielding structure is formed by horizontally connecting an external shielding layer and at least one first conductive structure to form a closed figure, and there is a potential difference between the two ends of the first conductive structure; the magnetic tunnel junction and the external shielding layer are both obtained by synchronous etching based on the magnetic tunnel junction film stack.

[0008] In some possible examples, a plurality of magnetic tunnel junctions and an internal shielding structure are provided within a data storage structure; the internal shielding structure is disposed at intervals between at least two magnetic tunnel junctions and is connected to an external shielding structure at at least one end; the internal shielding structure includes at least an internal shielding layer, and the magnetic tunnel junctions, the external shielding layer, and the internal shielding layer are all obtained by synchronous etching based on a magnetic tunnel junction film stack.

[0009] In some possible examples, the internal shielding structure is formed by horizontally connecting an internal shielding layer and at least one second conductive structure, and there is a potential difference between both ends of the second conductive structure.

[0010] In some possible examples, a plurality of magnetic tunnel junctions and an internal shielding structure are provided within a data storage structure; the internal shielding structure is disposed at intervals between at least two magnetic tunnel junctions and is not connected to an external shielding structure; the internal shielding structure is formed by horizontally connecting an internal shielding layer and at least one second conductive structure, and there is a potential difference between both ends of the second conductive structure; the magnetic tunnel junctions, the external shielding layer, and the internal shielding layer are all obtained by synchronous etching based on a magnetic tunnel junction film stack.

[0011] In some possible examples, the data storage structure further includes a third conductive structure disposed beside the magnetic tunnel junction, and the third conductive structure is connected to an external circuit to form a read path; the third conductive structure is formed synchronously with the first conductive structure.

[0012] In some possible examples, the heavy metal layers correspondingly disposed below the magnetic tunnel junctions and the external shielding layer are formed synchronously.

[0013] In some possible examples, the external shielding layer is a ring structure, and the minimum distance between its two opposite side walls is not less than the minimum width of the magnetic tunnel junction.

[0014] According to some embodiments, the present application further provides a semiconductor storage structure, including at least:

[0015] A data storage structure and a shielding structure; the data storage structure includes a plurality of magnetic tunnel junctions; the shielding structure includes an external shielding structure and an internal shielding structure, the external shielding structure is disposed on the outer periphery of the data storage structure, the internal shielding structure is disposed at intervals between at least two magnetic tunnel junctions and is connected to the external shielding structure at at least one end; the external shielding structure is formed by an external shielding layer, the internal shielding structure is formed by horizontally connecting an internal shielding layer and at least one second conductive structure, and there is a potential difference between both ends of the second conductive structure; the magnetic tunnel junctions, the external shielding layer, and the internal shielding layer are all obtained by synchronous etching based on a magnetic tunnel junction film stack.

[0016] In some possible examples, the heavy metal layers correspondingly disposed below the magnetic tunnel junctions and the external shielding layer are formed synchronously.

[0017] In some possible examples, the external shielding layer is in a ring structure, and the minimum distance between its two opposite side walls is not less than the minimum width of the magnetic tunnel junction.

[0018] The semiconductor storage structure provided by the embodiments of the present application has at least the following advantages:

[0019] In the semiconductor storage structure of the embodiments of the present application, by providing an external shielding structure on the outer periphery of the data storage structure, the shielding structure is a closed figure formed by horizontally connecting an external shielding layer and at least one first conductive structure, and there is a potential difference between the two ends of the first conductive structure, which can realize the electromagnetic shielding of the data storage structure, effectively isolate the electromagnetic interference between adjacent devices and external electromagnetic interference, and reduce the read / write error rate. At the same time, the external shielding structure and the magnetic tunnel junctions in the data storage structure are both obtained by synchronous etching based on the same magnetic tunnel junction film stack, without the need to additionally add new magnetic shielding materials and corresponding manufacturing steps, which simplifies the manufacturing process and reduces the manufacturing cost while.

[0020] According to some embodiments, a manufacturing method of a semiconductor storage structure provided by the present application includes the steps of:

[0021] Deposit and etch a magnetic tunnel junction film stack to synchronously form a magnetic tunnel junction and an external shielding layer, the external shielding layer is formed on the outer periphery of the magnetic tunnel junction, and there is at least one magnetic tunnel junction; form at least one gap in the external shielding layer, and form a first conductive structure in the gap, the external shielding layer and the first conductive structure are horizontally connected to form an external shielding structure, and the external shielding structure is a closed figure; there is a potential difference between the two ends of the first conductive structure.

[0022] In some possible examples, etch the magnetic tunnel junction film stack to synchronously form a plurality of magnetic tunnel junctions, an external shielding layer and an internal shielding layer; the internal shielding layer is formed at the interval between at least two magnetic tunnel junctions to form an internal shielding structure, and at least one end of the internal shielding structure is connected to the external shielding structure;

[0023] Alternatively, etch the magnetic tunnel junction film stack to synchronously form a plurality of magnetic tunnel junctions, an external shielding layer and an internal shielding layer; the internal shielding layer is formed at the interval between at least two magnetic tunnel junctions to form an internal shielding structure, and at least one end of the internal shielding structure is connected to the external shielding structure; form at least one gap in the internal shielding layer, and form a second conductive structure in the gap, the internal shielding layer and the second conductive structure are horizontally connected to form an internal shielding structure; there is a potential difference between the two ends of the second conductive structure.

[0024] The manufacturing method of the semiconductor storage structure in the embodiments of the present application has at least the following advantages:

[0025] In the manufacturing method of the semiconductor storage structure according to the embodiments of the present application, an external shielding structure is provided on the outer periphery of the data storage structure. The shielding structure is a closed figure formed by horizontally connecting an external shielding layer and at least one first conductive structure, and there is a potential difference between the two ends of the first conductive structure, which can achieve electromagnetic shielding of the data storage structure, effectively isolate electromagnetic interference between adjacent devices and external electromagnetic interference, and reduce the read / write error rate. At the same time, the external shielding structure and the magnetic tunnel junction in the data storage structure are both obtained by synchronous etching based on the same magnetic tunnel junction film stack, without the need to additionally add new magnetic shielding materials and corresponding manufacturing steps, which simplifies the manufacturing process and reduces the manufacturing cost while. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a top view of the first semiconductor storage structure in an embodiment of the present application.

[0027] Figure 2 It is a schematic cross-sectional view of the first semiconductor storage structure in an embodiment of the present application along the A-A' direction.

[0028] Figure 3 It is a top view of the second semiconductor storage structure in an embodiment of the present application.

[0029] Figure 4 It is a schematic cross-sectional view of the second semiconductor storage structure in an embodiment of the present application along the B-B' direction.

[0030] Figure 5 It is a top view of the third semiconductor storage structure in an embodiment of the present application.

[0031] Figure 6 It is a schematic cross-sectional view of the third semiconductor storage structure in an embodiment of the present application along the B-B' direction.

[0032] Figure 7 It is a top view of the fourth semiconductor storage structure in an embodiment of the present application.

[0033] Figure 8 It is a schematic cross-sectional view of the fourth semiconductor storage structure in an embodiment of the present application along the A-A' direction.

[0034] Figure 9 It is a schematic cross-sectional view of the fifth semiconductor storage structure in an embodiment of the present application along the B-B' direction.

[0035] Figure 10 It is a top view of the fifth semiconductor storage structure in an embodiment of the present application.

[0036] Figure 11 It is a schematic cross-sectional view of the fifth semiconductor storage structure in an embodiment of the present application along the A-A' direction.

[0037] Figure 12 The flowchart of the manufacturing method of the first semiconductor storage structure in an embodiment of the present application.

[0038] Figure 13 The top view of the first semiconductor storage structure in an embodiment of the present application after etching the external shielding layer to form a void.

[0039] Figure 14 The cross-sectional schematic view of the first semiconductor storage structure in an embodiment of the present application after etching the external shielding layer to form a void along the A-A' direction.

[0040] Explanation of reference numerals:

[0041] 10 - Semiconductor storage structure; 21 - Magnetic tunnel junction; 22 - Top electrode; 23 - Third conductive structure; 24 - Heavy metal layer; 30 - External shielding structure; 31 - External shielding layer; 32 - First conductive structure; 40 - Bottom electrode; 50 - Internal shielding structure; 51 - Internal shielding layer; 52 - Second conductive structure; 60 - Void; 70 - Interconnect via. Detailed implementation manners

[0042] During the read and write processes of the magnetic memory, the electromagnetic fields in the external environment (such as power supplies, radio waves, etc.) and the electromagnetic fields of adjacent devices during read and write will cause certain interference to the storage devices. Especially when the density of the storage devices increases, the distance between the storage devices becomes shorter, or when the same adjacent storage device is repeatedly read and written at a high frequency, this kind of electromagnetic influence will be aggravated, resulting in an increase in the read and write error rate of the storage devices.

[0043] To solve the above problems, the prior art usually coats an additional magnetic shielding layer outside the magnetic tunnel junction or the storage chip to reduce the electromagnetic interference of adjacent devices and external magnetic field interference and lower the read and write error rate. However, this method requires adding the manufacturing step of the magnetic shielding layer outside the manufacturing process of the magnetic memory, increasing the additional process and manufacturing cost.

[0044] In the semiconductor storage structure in the embodiment of the present application, by providing an external shielding structure on the outer periphery of the data storage structure, the shielding structure is a closed figure formed by horizontally connecting an external shielding layer and at least one first conductive structure, and there is a potential difference at both ends of the first conductive structure, which can realize the electromagnetic shielding of the data storage structure to effectively isolate the electromagnetic interference of adjacent devices and external electromagnetic interference and lower the read and write error rate. At the same time, the external shielding structure and the magnetic tunnel junction in the data storage structure are synchronously etched based on the same magnetic tunnel junction film stack, without the need to additionally add new magnetic shielding materials and corresponding manufacturing steps, simplifying the manufacturing process while reducing the manufacturing cost.

[0045] To make the above objects, features, and advantages of the embodiments of the present application more apparent and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments of the present application are only partial embodiments of the present application, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

[0046] An embodiment of the present application provides a semiconductor storage structure, which at least includes:

[0047] A data storage structure and an external shielding structure disposed on the outer periphery of the data storage structure; the data storage structure includes at least one magnetic tunnel junction; the external shielding structure is formed by horizontally connecting an external shielding layer and at least one first conductive structure to form a closed figure, and there is a potential difference between both ends of the first conductive structure; both the magnetic tunnel junction and the external shielding layer are obtained by synchronous etching based on a magnetic tunnel junction film stack.

[0048] Reference Figure 1 and Figure 2 , which is a schematic diagram of the first semiconductor storage structure 10 provided by the embodiment of the present application, at least including: a data storage structure and an external shielding structure 30 disposed on the outer periphery of the data storage structure; there are multiple magnetic tunnel junctions 21 in the data storage structure; the external shielding structure 30 is formed by horizontally connecting an external shielding layer 31 and at least one first conductive structure 32 to form a closed figure, and there is a potential difference between both ends of the first conductive structure 32; both the magnetic tunnel junction 21 and the external shielding layer 31 are obtained by synchronous etching based on a magnetic tunnel junction film stack.

[0049] In the semiconductor storage structure 10 provided in this embodiment, the magnetic tunnel junction 21 is a core component of the data storage structure and is used for data storage. Its structure is a multi-layer composite film stack structure (not shown in the figure), including: a free layer, a barrier layer, and a reference layer. The materials of the free layer and the reference layer can be ferromagnetic materials, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc. and their alloys, or antiferromagnetic materials; the free layer and the reference layer can be single-layer or multi-layer composite film layers; the material of the barrier layer is an insulating material, such as magnesium oxide, aluminum oxide, silicon oxide, etc. In addition, a pinning layer can be provided in the magnetic tunnel junction 21, located on the side of the reference layer away from the barrier layer to fix the magnetization direction of the reference layer.

[0050] The shape of the magnetic tunnel junction 21 is oval, or it can also be circular, triangular, rhombic, etc. Figure 1 The top view in

[0051] Multiple magnetic tunnel junctions 21 can be provided. The multiple magnetic tunnel junctions 21 are arranged in an array or arranged in regions according to storage requirements, functions, etc.; only one magnetic tunnel junction 21 can also be provided. Those skilled in the art can flexibly set the number and arrangement mode of the magnetic tunnel junctions 21 according to their actual needs, and no limitation is made here.

[0052] In the data storage structure, each magnetic tunnel junction 21 is provided with a write path and a read path corresponding to it one by one. For the convenience of description, the write path and the read path provided for each magnetic tunnel junction 21 one by one are named data storage units. Figure 2 The first data storage unit in this embodiment is shown and includes: a magnetic tunnel junction 21, a top electrode 22, a heavy metal layer 24, and a bottom electrode 40. The bottom electrode 40 is provided at both ends of the heavy metal layer 24 so that a write current flows through the heavy metal layer 24 to form a write path and realize data writing of the magnetic tunnel junction 21; the top electrode 22 and any one of the bottom electrodes 40 below the heavy metal layer 24 form a read path to realize data reading of the magnetic tunnel junction 21.

[0053] Specifically, in the semiconductor storage structure 10 of this embodiment, the free layer of the magnetic tunnel junction 21 is adjacent to the heavy metal layer 24. When the write current flows through the heavy metal layer 24 via the bottom electrode 40, the heavy metal layer 24 generates a spin current, which can induce the magnetic moment of the free layer to change direction. When the write current direction is different, the magnetic moment direction of the free layer is also different, so that it shows a parallel state or an anti-parallel state with the magnetic moment direction of the reference layer, and the magnetic tunnel junction 21 shows a low-resistance state or a high-resistance state to store the data "0" or "1"; by applying a read current to the magnetic tunnel junction 21 between the top electrode 22 and the bottom electrode 40, the resistance state of the magnetic tunnel junction 21 can be obtained to obtain a specific storage value.

[0054] The heavy metal layer 24 is a material with strong spin-orbit coupling effect and conductivity, including single substances such as platinum, tantalum, tungsten and their alloys, and its structure can be a single layer or a multi-layer composite structure.

[0055] Since the heavy metal layer 24 is provided below the magnetic tunnel junction 21, and the magnetic tunnel junction 21 and the external shielding layer 31 are both obtained by synchronous etching based on the magnetic tunnel junction film stack, therefore, a heavy metal layer 24 is also synchronously provided below the external shielding structure 30. It should be noted that the heavy metal layer 24 below the magnetic tunnel junction 21 and the heavy metal layer 24 below the external shielding structure 30 are not connected to each other.

[0056] Furthermore, in order to reduce the logic circuit area at the top of the magnetic tunnel junction 21 in the data storage unit and increase the integration of the functional modules of the storage chip, a third conductive structure 23 can be provided beside the magnetic tunnel junction 21 to connect the reading circuit from the top electrode 22 to the logic circuit at the bottom of the third conductive structure 23 (the connection relationship is not shown in the figure). The third conductive structure 23 and the first conductive structure 32 are both conductive materials, such as metal or alloy, and the two can be formed simultaneously from the same material.

[0057] The external shielding layer 31 and the magnetic tunnel junction 21 are both obtained based on the synchronous etching of the magnetic tunnel junction film stack. It can be understood that the magnetic tunnel junction film stack structure and materials forming the external shielding layer 31 and the magnetic tunnel junction 21 are exactly the same. For example, taking the magnetic tunnel junction film stack from bottom to top including the free layer / barrier layer / reference layer as an example, the external shielding layer 31 and the magnetic tunnel junction 21 formed by the synchronous etching of the magnetic tunnel junction film stack also include the above-mentioned free layer / barrier layer / reference layer, and the two are consistent in terms of film stacking method, film material and film thickness. In addition, the process of the external shielding layer 31 and the magnetic tunnel junction 21 is completely synchronized, which can simplify the process steps and reduce manufacturing costs.

[0058] refer to Figure 1 The top view shows that the external shielding structure 30 is formed by horizontally connecting the external shielding layer 31 and at least one first conductive structure 32 to form a closed figure. Since the magnetic tunnel junction 21 and the external shielding layer 31 are obtained by synchronous etching based on the magnetic tunnel junction film stack, the free layer / reference layer and other film layers in the external shielding layer 31 are conductive and are horizontally connected to the first conductive structure 32 to form a conductive whole. The potentials of the internal parts of the external shielding structure 30 are equal. At this time, the two ends of the first conductive structure 32 have a potential difference, such as connecting one end to a low-potential circuit or grounding. The external shielding structure 30 forms an effective Faraday cage that can shield the external electromagnetic field. When the external electromagnetic field acts, the free electrons on the surface of the external shielding structure 30 are redistributed to generate an electric field opposite to the external electric field, thereby offsetting the external electric field; for external high-frequency electromagnetic waves, the conductive material in the external shielding structure 30 can also reflect and absorb electromagnetic waves, further weakening their entry into the internal data storage area, isolating the external environment and the electromagnetic interference generated by the magnetic storage device in the adjacent area during high-frequency reading and writing, and reducing the read and write error rate.

[0059] There is at least one first conductive structure 32 in the external shielding structure 30. It can be understood that as the number of magnetic tunnel junctions 21 in the data storage structure increases, the area of the external shielding layer 31 will also increase accordingly, and the electromagnetic induction lines concentrated in the external shielding layer 31 will increase. Since the degree of absorption of electromagnetic waves by materials is restricted by various factors such as the properties of the materials (conductivity, permeability, dielectric constant, etc.), the frequency of electromagnetic waves, the thickness of the materials, and the external environment (temperature, humidity, etc.), in order to achieve a better magnetic shielding effect, multiple first conductive structures 32 can be arranged in the external shielding structure 30. Preferably, the multiple first conductive structures 32 are evenly arranged at equal distances to timely export the electromagnetic waves absorbed by the materials in the external shielding layer 31 to the low-potential circuit or ground wire through the first conductive structures 32, further improving the electromagnetic shielding effect.

[0060] The external shielding layer 31 is a ring structure, and its shape can be a circular ring, an elliptical ring, a square ring, a rectangular ring, a polygonal ring, etc., which is not limited here. Refer to Figure 1 , the minimum distance w1 between two opposite side walls of the external shielding layer 31 should not be less than the minimum width w2 of the magnetic tunnel junction 21 to ensure that the external shielding layer 31 can effectively isolate electromagnetic interference; in addition, a smaller size of the external shielding layer 31 will increase the manufacturing process difficulty and cost, such as requiring high-precision etching methods and high-resolution lithography machines, etc. In this embodiment, the minimum distance w1 between two opposite side walls of the external shielding layer 31 is not less than the minimum width w2 of the magnetic tunnel junction 21, without the need for high-precision lithography and etching technologies, reducing the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0061] Continue to refer to Figure 2 , the top surface of the first conductive structure 32 should not be lower than the top surface of the external shielding layer 31 to ensure that each conductive film layer in the external shielding layer 31, such as the free layer and the reference layer, can be horizontally connected to the first conductive structure 32. In particular, when the third conductive structure 23 and the first conductive structure 32 are formed synchronously, to ensure that the third conductive structure 23 can be electrically connected to the top electrode 22, the top surface of the third conductive structure 23 should not be lower than the top surface of the top electrode 22. At this time, the top surface of the first conductive structure 32 is higher than the top surface of the magnetic tunnel junction 21, that is, the top surface of the first conductive structure 32 is higher than the top surface of the external shielding layer 31.

[0062] A bottom electrode 40 can be arranged below the first conductive structure 32 to facilitate connection to the low-potential circuit or ground wire below; a bottom electrode 40 can also be arranged below the third conductive structure 23 to facilitate connection to the logic circuit below. It should be noted that the bottom electrodes 40 below the magnetic tunnel junction 21, the first conductive structure 32, and the third conductive structure 23 are not electrically connected to each other.

[0063] Further, the bottom electrode 40 is disposed in the substrate (not shown in the figure). The material of the substrate may be a semiconductor material, such as silicon, silicon carbide, gallium nitride, aluminum nitride, etc., or an insulating material, such as germanium. A logic circuit and a low-potential circuit or a ground wire, etc. are also disposed in the substrate. The logic circuit is electrically connected to the third conductive structure 23, and the low-potential circuit or the ground wire is connected to the first conductive structure 32, which can be selected according to actual manufacturing requirements.

[0064] The embodiment of the present application also provides a second semiconductor storage structure. Refer to Figure 3 and Figure 4 , the difference between the semiconductor storage structure 10 and the first semiconductor storage structure is mainly that: the data storage structure includes a plurality of magnetic tunnel junctions 21 and an internal shielding structure 50; the internal shielding structure 50 is disposed at intervals between at least two magnetic tunnel junctions 21, and at least one end is connected to the external shielding structure 30; the internal shielding structure 50 includes at least an internal shielding layer 51, and the magnetic tunnel junctions 21, the external shielding layer 31, and the internal shielding layer 51 are all obtained by synchronous etching based on a magnetic tunnel junction film stack.

[0065] In this embodiment, the internal shielding structure 50 is disposed at intervals between at least two magnetic tunnel junctions 21, that is, the internal shielding structure 50 is disposed at intervals between at least two first data storage units, such as at intervals between every two of a plurality of first data storage units, at intervals between adjacent two columns of first data storage units arranged in a matrix, or at intervals between every two first data storage units, etc., which can be flexibly set according to actual needs.

[0066] The magnetic tunnel junctions 21, the external shielding layer 31, and the internal shielding layer 51 are all obtained by synchronous etching based on a magnetic tunnel junction film stack. It can be understood that the magnetic tunnel junction film stack structures and materials for forming the internal shielding layer 51, the external shielding layer 31, and the magnetic tunnel junctions 21 are completely the same. For example, taking the magnetic tunnel junction film stack including a free layer / barrier layer / reference layer from bottom to top, the external shielding layer 31, the internal shielding layer 51, and the magnetic tunnel junctions 21 formed based on this magnetic tunnel junction film stack also include the above free layer / barrier layer / reference layer. The three are consistent in terms of film layer stacking method, film layer material, and film layer thickness, etc. Moreover, the manufacturing process of the internal shielding layer 51, the external shielding layer 31, and the magnetic tunnel junctions 21 is completely synchronous. Through one manufacturing process of the magnetic tunnel junctions 21, the internal shielding layer 51 and the external shielding layer 31 can be obtained simultaneously, which simplifies the process manufacturing process and reduces the production and manufacturing cost.

[0067] At least one end of the internal shielding structure 50 is connected to the external shielding structure 30, or both ends are connected to the external shielding structure 30. Refer to Figure 3 and Figure 4In the semiconductor storage structure 10 shown, one end of the internal shielding structure 50 is connected to the external shielding structure 30, and the internal shielding layer 51 and the conductive material layers in the external shielding layer 31 are horizontally connected to form a conductive whole, and the potential inside the conductive whole is equal. At this time, the two ends of the first conductive structure 32 have a potential difference, such as connecting one end to a low-potential circuit or grounding, and the external shielding structure 30 and the internal shielding layer 51 form an effective Faraday cage that can shield the external electromagnetic field. When the external electromagnetic field acts, the free electrons on the surface of the external shielding structure 30 and the internal shielding layer 51 are redistributed to generate an electric field opposite to the external electric field, thereby offsetting the external electric field; for external high-frequency electromagnetic waves, the conductive materials in the external shielding structure 30 and the internal shielding layer 51 can also reflect and absorb electromagnetic waves, weakening their entry into the internal data storage area, effectively isolating the external environment and the electromagnetic interference generated by the magnetic storage in the adjacent area during high-frequency reading and writing, and reducing the read and write error rate of the data storage structure.

[0068] Continue to refer Figure 3 As shown in the top view, the minimum distance w3 between the two opposite side walls of the internal shielding layer 51 should not be less than the minimum width w2 of the magnetic tunnel junction 21 to ensure that the internal shielding layer 51 can effectively isolate electromagnetic interference; in addition, the smaller size of the internal shielding layer 51 will increase the difficulty and cost of the manufacturing process, such as the need for high-precision etching methods and high-resolution lithography machines. In this embodiment, the minimum distance w3 between the two opposite side walls of the internal shielding layer 51 is not less than the minimum width w2 of the magnetic tunnel junction 21, and no high-precision lithography and etching technology is required, which reduces the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0069] To further enhance the electromagnetic shielding effect, at least one second conductive structure 52 can be provided inside the internal shielding structure 50. The second conductive structure 52 is horizontally connected to the internal shielding layer 51 to form the internal shielding structure 50. The two ends of the second conductive structure 52 have a potential difference, such as connecting one end to a low potential circuit or grounding. The second conductive structure 52 is combined with the first conductive structure 32 to timely guide the electromagnetic waves absorbed in the materials of the external shielding layer 31 and the internal shielding layer 51 to the low potential circuit or ground. The second conductive structure 52 is made of conductive material, such as metal or alloy, and the second conductive structure 52, the first conductive structure 32 and the third conductive structure 23 can be formed synchronously from the same material.

[0070] Multiple internal shielding structures can be set in the data storage structure at the same time, and technicians in this field can select and combine the positions of multiple internal shielding structures according to actual needs. For example, for a semiconductor storage structure containing different functional areas (such as long-term storage areas, data erase areas, etc.) in a data storage structure, the write current frequency, current size, and read and write times of the magnetic tunnel junctions in different functional areas may be different. The internal shielding structure can be set at the intervals of different functional areas to avoid electromagnetic interference between the functional areas. All selections and combinations of the number and relative positions of the internal shielding structures made by technicians in this field according to actual needs do not deviate from the technical concept of this application and fall within the scope of protection of this application. However, it should be noted that for any internal shielding structure, at least the following conditions must be met: there is at least one second conductive structure in the internal shielding structure, and / or at least one end of the internal shielding structure is horizontally connected to the external shielding structure having the first conductive structure, so as to ensure that the electromagnetic waves absorbed in the internal shielding layer material are guided out to the low-potential circuit or ground wire to achieve the electromagnetic shielding effect.

[0071] Since the semiconductor storage structure in the embodiment of the present application differs from the first semiconductor storage structure in the above embodiment only in the internal shielding structure, the cross-sectional schematic diagram of the semiconductor storage structure along the A-A' direction in the embodiment of the present application can be referred to. Figure 2 As shown. The heavy metal layer 24 is disposed below the magnetic tunnel junction 21. Since the magnetic tunnel junction 21, the external shielding layer 31 and the internal shielding layer 51 are all obtained by synchronous etching based on the magnetic tunnel junction film stack, the heavy metal layer 24 is also disposed below the external shielding structure 30 and the internal shielding structure 50. It is worth noting that the heavy metal layers 24 below the magnetic tunnel junction 21, the first conductive structure 32, the second conductive structure 52 and the third conductive structure 23 are not connected to each other.

[0072] In addition, the first data storage unit, the external shielding structure, etc. in the embodiment of the present application are the same as the first semiconductor storage structure and will not be described in detail here.

[0073] An embodiment of the present application also provides a third semiconductor storage structure, which is different from the second semiconductor storage structure mainly in that: the internal shielding structure is not connected to the external shielding structure; the internal shielding structure is formed by horizontally connecting the internal shielding layer and at least one second conductive structure, and the two ends of the second conductive structure have a potential difference.

[0074] Since the semiconductor storage structure in the embodiment of the present application differs from the first semiconductor storage structure in the above embodiment only in the internal shielding structure, the cross-sectional schematic diagram of the semiconductor storage structure along the A-A' direction in the embodiment of the present application can be referred to. Figure 2 . See Figure 5 , Figure 2 and Figure 6As shown, since the internal shielding structure 50 is not connected to the external shielding structure 30, it is necessary to set at least one second conductive structure 52 in the internal shielding structure 50 to promptly conduct the electromagnetic waves absorbed by the material in the internal shielding layer 51 to the low-potential circuit or ground wire to achieve electromagnetic shielding.

[0075] The first data storage unit, the external shielding structure, etc. in the embodiment of the present application are the same as the first semiconductor storage structure described above, and will not be described in detail here.

[0076] The present application also provides a fourth semiconductor storage structure, see Figures 7 to 9 The difference between the semiconductor storage structure 10 and the second semiconductor storage structure is that: the external shielding structure 30 is a closed figure formed by horizontally connecting the external shielding layer 31; the internal shielding structure 50 is formed by horizontally connecting the internal shielding layer 51 and at least one second conductive structure 52, and the two ends of the second conductive structure 52 have a potential difference.

[0077] The conductive material layers in the internal shielding layer 51 and the external shielding layer 31 are interconnected to form a conductive whole, and the potential at each point inside the conductive whole is equal. At this time, there is a potential difference at both ends of the second conductive structure 52, such as connecting one end to a low potential circuit or grounding. The external shielding structure 30 and the internal shielding structure 50 form an effective Faraday cage, which can shield the external electromagnetic field, effectively isolate the external environment and the electromagnetic interference generated by the magnetic storage device in the adjacent area during high-frequency reading and writing, and reduce the reading and writing error rate.

[0078] The present application also provides a fifth semiconductor storage structure, see Figure 10 and Figure 11 The semiconductor storage structure 10 is different from the first semiconductor storage structure mainly in that the structure of the data storage unit is different.

[0079] contrast Figure 2 and Figure 11 In the data storage structure of this embodiment, a top electrode 22 and a bottom electrode 40 are respectively disposed above and below the magnetic tunnel junction 21, and a heavy metal layer 24 is not involved. Figure 11 The second data storage unit in this embodiment is shown, including: a magnetic tunnel junction 21, a top electrode 22 and a bottom electrode 40. The bottom electrode 40 is correspondingly arranged below the magnetic tunnel junction 21, so that the write current and the read current flow between the top electrode 22-magnetic tunnel junction 21-bottom electrode 40, so as to realize the data writing and reading of the magnetic tunnel junction 21.

[0080] Specifically, when the write current flows through the magnetic tunnel junction 21 via the top electrode 22 and the bottom electrode 40, the write current is polarized to form a spin-polarized current. The spin electrons transfer the spin momentum to the magnetic moment of the free layer, causing the magnetic moment of the free layer to change direction. Different directions of the write current result in different directions of the magnetic moment of the free layer, which shows a parallel state or an anti-parallel state with the magnetic moment of the reference layer. The magnetic tunnel junction 21 shows a low-resistance state or a high-resistance state to store the data "0" or "1". A read current is applied to the magnetic tunnel junction 21 via the top electrode 22 and the bottom electrode 40 to obtain the resistance state of the magnetic tunnel junction 21 to acquire the specific stored value.

[0081] It can be understood that the data storage units in the second to fourth semiconductor storage structures provided by the embodiments of the present application can also be arranged by using the second data storage unit and similar data storage unit structures. The external shielding structure, internal shielding structure, etc. in the obtained semiconductor storage structure are the same as those in the second to fourth semiconductor storage structures, and will not be described in detail herein.

[0082] On the other hand, the embodiments of the present application also provide a manufacturing method of a semiconductor storage structure. The flowchart of the first manufacturing method is shown in Figure 12 , and includes the following steps:

[0083] Step S10: Deposit and etch the magnetic tunnel junction film stack to synchronously form a magnetic tunnel junction and an external shielding layer. The external shielding layer is formed on the outer periphery of the magnetic tunnel junction, and there is at least one magnetic tunnel junction.

[0084] Step S20: Form at least one void in the external shielding layer, and form a first conductive structure in the void. The external shielding layer and the first conductive structure are horizontally connected to form an external shielding structure, and the external shielding structure is a closed figure; there is a potential difference at both ends of the first conductive structure.

[0085] Figure 1 and Figure 2 are the top view and the cross-sectional schematic diagram along the A-A' direction of the semiconductor storage structure finally formed by the first manufacturing method of the embodiments of the present application. Among them, step S10 of the manufacturing method specifically includes:

[0086] S101: Form a bottom electrode, and sequentially deposit a heavy metal layer and a magnetic tunnel junction film stack above the bottom electrode. The bottom electrode is formed at both ends of the heavy metal layer.

[0087] S102: Etch the magnetic tunnel junction film stack to synchronously form at least one magnetic tunnel junction and an external shielding layer. The external shielding layer is formed on the outer periphery of the magnetic tunnel junction.

[0088] S103: Etch the heavy metal layer to cut off the electrical connection between the magnetic tunnel junction and the heavy metal layer below the external shielding structure.

[0089] The deposited heavy metal layer is a material with strong spin - orbit coupling effect and conductivity, including elements such as platinum, tantalum, tungsten and their alloys. Its structure can be a single layer or a multi - layer composite structure. The heavy metal layer is deposited above the magnetic tunnel junction film stack and adjacent to the free layer to utilize the spin - orbit effect to flip the magnetic moment direction of the free layer and achieve the writing of stored data.

[0090] The magnetic tunnel junction film stack (not shown in the figure) is a multi - layer composite film stack structure, including: a free layer, a barrier layer and a reference layer. The materials of the free layer and the reference layer can be ferromagnetic materials, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc., or antiferromagnetic materials. The free layer and the reference layer can be a single layer or a composite film layer. The material of the barrier layer is an insulating material, such as magnesium oxide, aluminum oxide, silicon oxide, etc. In addition, a pinning layer can be set in the magnetic tunnel junction film stack, located on the side of the reference layer away from the barrier layer to fix the magnetization direction of the reference layer.

[0091] The bottom electrode can be formed in the substrate (not shown in the figure). The magnetic tunnel junction film stack is deposited above the substrate. The shape of the substrate can be various shapes such as circular, rectangular, rhombic, etc., and can be selected according to actual manufacturing requirements. The material of the substrate can be a semiconductor material, such as silicon, silicon carbide, gallium nitride, aluminum nitride, etc., or an insulating material, such as germanium. Logic circuits and low - potential circuits or ground wires are also provided in the substrate.

[0092] For step S102, pattern and etch the magnetic tunnel junction film stack to simultaneously form a magnetic tunnel junction and an external shielding layer. The external shielding layer is formed on the outer periphery of the magnetic tunnel junction.

[0093] Refer to Figure 13 and Figure 14 , the formed magnetic tunnel junction 21 is used for data storage. Its shape can be oval, circular, triangular, rhombic, etc. Figure 13 The top - view in is only a schematic of the magnetic tunnel junction 21, and there is no limitation on the shape of the magnetic tunnel junction 21.

[0094] After etching the magnetic tunnel junction film stack, multiple magnetic tunnel junctions 21 can be formed simultaneously. The multiple magnetic tunnel junctions 21 are arranged in an array or arranged in regions according to storage requirements, functions, etc. Only one magnetic tunnel junction 21 can also be formed. Those skilled in the art can flexibly set the number and arrangement method of the magnetic tunnel junctions 21 according to their actual needs, and there is no limitation here.

[0095] The external shielding layer 31 is a ring - shaped structure. Its shape can be a circular ring, an elliptical ring, a square ring, a rectangular ring, a polygonal ring, etc., and there is no limitation here. Refer to Figure 13, the minimum distance w1 between two opposite sidewalls of the external shielding layer 31 should be no less than the minimum width w2 of the magnetic tunnel junction 21 to ensure that the external shielding layer 31 can effectively isolate electromagnetic interference; in addition, a smaller size of the external shielding layer 31 will increase the manufacturing process difficulty and cost, such as requiring high-precision etching methods and high-resolution lithography machines, etc. In this embodiment, the minimum distance w1 between two opposite sidewalls of the external shielding layer 31 is no less than the minimum width w2 of the magnetic tunnel junction 21, without the need for high-precision lithography and etching technologies, reducing the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0096] The external shielding layer 31 and the magnetic tunnel junction 21 are both obtained by synchronous etching based on the magnetic tunnel junction film stack. For example, taking the magnetic tunnel junction film stack including a free layer / barrier layer / reference layer from bottom to top as an example, the external shielding layer 31 and the magnetic tunnel junction 21 formed by synchronous etching based on this magnetic tunnel junction film stack also include the above free layer / barrier layer / reference layer, and they are consistent in terms of film layer stacking method, film layer material, and film layer thickness. Moreover, the process of the external shielding layer 31 and the magnetic tunnel junction 21 is completely synchronous, which can simplify the process steps and reduce the manufacturing cost.

[0097] For step S103, etch the heavy metal layer to cut off the electrical connection between the magnetic tunnel junction and the heavy metal layer below the external shielding structure.

[0098] Refer to Figure 14 , since the heavy metal layer 24 is formed below the magnetic tunnel junction 21, and the external shielding layer 31 and the magnetic tunnel junction 21 are both obtained by synchronous etching based on the magnetic tunnel junction film stack, therefore, the heavy metal layer 24 is also synchronously formed below the external shielding structure 30. To avoid short-circuiting of the magnetic tunnel junction 21, the electrical connection between the heavy metal layer 24 below the magnetic tunnel junction 21 and the heavy metal layer 24 below the external shielding structure 30 should be cut off.

[0099] For step S20, refer to Figure 13 and Figure 14 , etch the external shielding layer 31 to form at least one gap 60 in the annular external shielding layer 31, and deposit a conductive material in the gap 60 to form a first conductive structure. The gap 60 can be formed by etching the external shielding layer 31 again after the magnetic tunnel junction 21 is formed; it can also be formed synchronously in the external shielding layer 31 when etching the magnetic tunnel junction film stack to form the magnetic tunnel junction 21; the size of the gap 60 needs to partially or completely cut off the horizontal connection of each film layer in the external shielding layer 31 to ensure that after filling the conductive material in the gap 60 to form the first conductive structure, each film layer in the external shielding layer 31 can be horizontally connected to the first conductive structure.

[0100] Continue to refer to Figure 1 and Figure 2, the external shielding layer 31 and the first conductive structure 32 are horizontally connected to form a closed external shielding structure 30. Since both the magnetic tunnel junction 21 and the external shielding layer 31 are obtained by synchronous etching based on the magnetic tunnel junction film stack, the material layers such as the free layer / reference layer in the external shielding layer 31 have conductivity and are all horizontally connected to the first conductive structure 32 to form a conductive whole, and the potential at each part inside the external shielding structure 30 is equal. At this time, a potential difference is applied across the two ends of the first conductive structure 32. For example, one end is connected to a low-potential circuit or grounded. The external shielding structure 30 forms an effective Faraday cage, which can shield external electromagnetic fields. When an external electromagnetic field acts, the free electrons on the surface of the external shielding structure 30 redistribute to generate an electric field opposite to the external electric field, thereby canceling the external electric field. For external high-frequency electromagnetic waves, the conductive materials in the external shielding structure 30 can also reflect and absorb the electromagnetic waves, further weakening their entry into the internal data storage area, effectively isolating the external environment and the electromagnetic interference generated by adjacent magnetic memories during high-frequency reading and writing, and reducing the read / write error rate of the data storage structure.

[0101] There is at least one first conductive structure 32. It can be understood that as the number of magnetic tunnel junctions 21 in the data storage structure increases, the area of the external shielding layer 31 will also increase accordingly, and the electromagnetic induction lines concentrated in the external shielding layer 31 increase. Since the absorption degree of electromagnetic waves by materials is restricted by various factors such as the properties of the materials (conductivity, permeability, dielectric constant, etc.), the frequency of electromagnetic waves, the thickness of the materials, and the external environment (temperature, humidity, etc.), in order to achieve a better magnetic shielding effect, multiple first conductive structures 32 can be provided in the external shielding structure 30. Preferably, the multiple first conductive structures 32 are arranged equidistantly and uniformly to timely conduct the electromagnetic waves absorbed by the materials in the external shielding layer 31 to the low-potential circuit or the ground wire through the first conductive structures 32.

[0102] A top electrode 22 is also correspondingly formed above the magnetic tunnel junction 21. Both the top electrode 22 and the bottom electrode 40 are made of conductive materials such as metals or alloys. Their materials can be the same or different, and both are used for the electrical connection between the magnetic tunnel junction 21 and the outside. The bottom electrode 40 is formed at both ends of the heavy metal layer 24 so that the writing current flows through the heavy metal layer 24 to form a writing path to realize data writing of the magnetic tunnel junction 21; the top electrode 22 and any one of the bottom electrodes 40 below the heavy metal layer 24 form a reading path to realize data reading of the magnetic tunnel junction 21.

[0103] For the convenience of description, each magnetic tunnel junction 21 and its corresponding writing path and reading path are named as a data storage unit. Figure 2The first data storage unit in the manufacturing method of this embodiment is shown as follows, including: a magnetic tunnel junction 21, a top electrode 22, a heavy metal layer 24, and a bottom electrode 40. In this embodiment, the free layer of the magnetic tunnel junction 21 is adjacent to the heavy metal layer 24. When the write current flows through the heavy metal layer 24 via the bottom electrode 40, the heavy metal layer 24 generates a spin current, which induces the magnetic moment of the free layer to change its direction. When the direction of the write current is different, the direction of the magnetic moment of the free layer is also different, so that it shows a parallel state or an anti-parallel state with the magnetic moment direction of the reference layer, and the magnetic tunnel junction 21 shows a low-resistance state or a high-resistance state to store the data "0" or "1"; by applying a read current between the top electrode 22 and the bottom electrode 40 to the magnetic tunnel junction 21, the resistance state of the magnetic tunnel junction 21 can be obtained to obtain the specific stored value.

[0104] Further, in order to reduce the area of the logic circuit on the top of the magnetic tunnel junction 21 in the data storage unit and increase the integration degree of the functional modules of the storage chip, a third conductive structure can be arranged beside the magnetic tunnel junction 21, and its structure refers to Figure 1 and Figure 2 shown. By electrically connecting the top electrode 22 and the third conductive structure 23 (the connection relationship is not shown in the figure), the read circuit is led out from the top electrode 22 to the logic circuit at the bottom of the third conductive structure 23 to form a read path. Both the third conductive structure 23 and the first conductive structure 32 are made of conductive materials, such as metals or alloys.

[0105] The third conductive structure 23 and the first conductive structure 32 can be formed synchronously, referring to Figure 13 and Figure 14 , and the specific process is as follows: after etching to form the magnetic tunnel junction 21, an interconnection via 70 is formed beside the magnetic tunnel junction 21. When depositing the conductive material in the void 60 to form the first conductive structure, the conductive material is synchronously deposited in the interconnection via 70 to form the third conductive structure.

[0106] Continue to refer to Figure 2 , the top surface of the first conductive structure 32 should not be lower than the top surface of the external shielding layer 31 to ensure that each conductive film layer in the external shielding layer 31, such as the free layer and the reference layer, can be horizontally connected to the first conductive structure 32. In particular, when the third conductive structure 23 and the first conductive structure 32 are formed synchronously, to ensure that the third conductive structure 23 can be electrically connected to the top electrode 22, the top surface of the third conductive structure 23 should not be lower than the top surface of the top electrode 22. At this time, the top surface of the first conductive structure 32 is higher than the top surface of the magnetic tunnel junction 21, that is, the top surface of the first conductive structure 32 is higher than the top surface of the external shielding layer 31.

[0107] A bottom electrode 40 is also formed below the first conductive structure 32. The upper end of the bottom electrode 40 is connected to the first conductive structure 32 to extend the length of the first conductive structure 32 and electrically connect it to a low-potential circuit or a ground wire below. A bottom electrode 40 may also be formed below the third conductive structure 23 to facilitate the connection of the third conductive structure 23 to the logic circuit below, which is not limited here. It should be noted that the bottom electrodes 40 below the magnetic tunnel junction 21, the bottom electrode 40 below the first conductive structure 32, and the bottom electrode 40 below the third conductive structure 23 are not electrically connected to each other.

[0108] This embodiment also provides a manufacturing method for the second semiconductor memory structure. Different from the first manufacturing method, the manufacturing method of this application embodiment further includes forming an internal shielding structure in the data storage structure. Step S102 specifically includes:

[0109] Deposit and etch the magnetic tunnel junction film stack to simultaneously form a plurality of magnetic tunnel junctions, an external shielding layer, and an internal shielding layer. The external shielding layer is formed on the outer periphery of the data storage structure; the internal shielding layer is formed at the intervals between at least two magnetic tunnel junctions.

[0110] In the manufacturing method of this embodiment, the internal shielding structure is arranged at the intervals between at least two magnetic tunnel junctions, that is, the internal shielding structure is arranged at the intervals between at least two first data storage units. For example, at the intervals between every two of a plurality of first data storage units, at the intervals between adjacent two columns of first data storage units arranged in a matrix, or at the intervals between every two first data storage units, etc., which can be flexibly set according to actual needs.

[0111] The magnetic tunnel junction, the external shielding layer, and the internal shielding layer are all obtained by synchronous etching based on the magnetic tunnel junction film stack. For example, taking the magnetic tunnel junction film stack including a free layer / barrier layer / reference layer from bottom to top, the external shielding layer, the internal shielding layer, and the magnetic tunnel junction formed by synchronous etching based on this magnetic tunnel junction film stack also include the above free layer / barrier layer / reference layer. The three are consistent in terms of film layer stacking method, film layer material, and film layer thickness. Moreover, the manufacturing process of the internal shielding layer, the external shielding layer, and the magnetic tunnel junction is completely synchronous. Through one manufacturing process of the magnetic tunnel junction, the internal shielding layer and the external shielding layer can be obtained simultaneously, simplifying the process manufacturing process and reducing the production and manufacturing cost.

[0112] In the manufacturing method of this embodiment, when etching the magnetic tunnel junction film stack, one end of the internal shielding layer can be connected to the external shielding layer, or both ends of the internal shielding layer can be connected to the external shielding structure.

[0113] Figure 3 and Figure 4The top view and the cross-sectional schematic diagram along the BB' direction of the semiconductor storage structure formed by the manufacturing method of the embodiment of the present application are respectively, wherein one end of the internal shielding structure 50 is connected to the external shielding structure 30, and the internal shielding layer 51 and the conductive material layers in the external shielding layer 31 are horizontally connected to form a conductive whole, and the potential inside the conductive whole is equal. At this time, the two ends of the first conductive structure 32 have a potential difference, such as connecting one end to a low potential circuit or grounding, and the external shielding structure 30 and the internal shielding layer 51 form an effective Faraday cage that can shield the external electromagnetic field. When the external electromagnetic field acts, the free electrons on the surface of the external shielding structure 30 and the internal shielding layer 51 are redistributed to generate an electric field opposite to the external electric field, thereby offsetting the external electric field; for external high-frequency electromagnetic waves, the conductive materials in the external shielding structure 30 and the internal shielding layer 51 can also reflect and absorb electromagnetic waves, weakening their entry into the internal data storage area, effectively isolating the external environment and the electromagnetic interference generated by the magnetic storage device in the adjacent area during high-frequency reading and writing, and reducing the read and write error rate of the data storage structure.

[0114] Since the heavy metal layer 24 is deposited under the magnetic tunnel junction 21, the magnetic tunnel junction 21, the external shielding layer 31 and the internal shielding layer 51 are all obtained by synchronous etching based on the magnetic tunnel junction film stack. Therefore, a heavy metal layer 24 is also provided under the external shielding structure 30 and the internal shielding structure 50. It is worth noting that the heavy metal layer 24 under the magnetic tunnel junction 21, the heavy metal layer 24 under the first conductive structure 32, the heavy metal layer 24 under the second conductive structure 52 and the heavy metal layer 24 under the third conductive structure 23 are not connected to each other.

[0115] Continue reading Figure 3 As shown in the top view, the minimum distance w3 between the two opposite side walls of the internal shielding layer 51 should not be less than the minimum width w2 of the magnetic tunnel junction to ensure that the internal shielding layer 51 can effectively isolate electromagnetic interference; in addition, the smaller size of the internal shielding layer 51 will increase the difficulty and cost of the manufacturing process, such as the need for high-precision etching methods and high-resolution lithography machines. In this embodiment, the minimum distance w3 between the two opposite side walls of the internal shielding layer 51 is not less than the minimum width w2 of the magnetic tunnel junction, and no high-precision lithography and etching technology is required, which reduces the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0116] The conductive magnetic material layers in the internal shielding layer 51 and the external shielding layer 31 are horizontally connected into a conductive whole, and the potential at each point inside the conductive whole is equal. At this time, a potential difference is created at both ends of the first conductive structure 32. For example, one end is connected to a low-potential circuit or grounded. The external shielding structure 30 and the internal shielding layer 51 form an effective Faraday cage, which can shield external electromagnetic fields. When an external electromagnetic field acts, the free electrons on the surfaces of the external shielding structure 30 and the internal shielding layer 51 redistribute, generating an electric field opposite to the external electric field, thereby canceling out the external electric field; for external high-frequency electromagnetic waves, the conductive materials in the external shielding structure 30 and the internal shielding layer 51 can also reflect and absorb electromagnetic waves, weakening their entry into the internal data storage area, effectively isolating the electromagnetic interference generated by the external environment and adjacent magnetic memories during high-frequency reading and writing, and reducing the read / write error rate of the data storage structure.

[0117] To further enhance the electromagnetic shielding effect, at least one second conductive structure can also be formed inside the internal shielding structure. The specific steps include:

[0118] Step S30: Etch the internal shielding layer to form at least one void in the internal shielding layer, and deposit a conductive material in the void to form the second conductive structure. At this time, the internal shielding layer and the second conductive structure are horizontally connected to form the internal shielding structure, and there is a potential difference at both ends of the second conductive structure.

[0119] Continue to refer to Figure 3 and Figure 4 , by connecting one end of the second conductive structure 52 to a low-potential circuit or grounding, the second conductive structure 52 combines with the first conductive structure 32 to timely conduct the electromagnetic waves absorbed by the materials of the external shielding layer 31 and the internal shielding layer 51 to the low-potential circuit or ground wire, strengthening the electromagnetic shielding effect. The material of the second conductive structure 52 is a conductive material, such as metal or alloy, etc. The second conductive structure 52, the first conductive structure 32, and the third conductive structure 23 can be formed synchronously from the same material.

[0120] In addition, referring to Figure 5 and Figure 6 for the semiconductor storage structure 10 shown, the internal shielding structure 50 may not be connected to the external shielding structure 30. Therefore, at least one second conductive structure 52 needs to be formed in the internal shielding structure 50 to timely conduct the electromagnetic waves absorbed by the materials in the internal shielding layer 51 to the low-potential circuit or ground wire to achieve electromagnetic shielding.

[0121] There is at least one internal shielding structure, and multiple internal shielding structures can be formed simultaneously in the data storage structure. Those skilled in the art can select and combine the positions of the multiple internal shielding structures according to actual needs. For example, for a semiconductor storage structure with different functional areas (such as a long-term storage area, a data erasure area, etc.) included in the data storage structure, the write current frequencies, current magnitudes, and read / write times of the magnetic tunnel junctions in different functional areas may vary. The internal shielding structure can be arranged at the intervals between different functional areas to avoid electromagnetic interference between the functional areas. All the selections and combinations made by those skilled in the art regarding the number and relative positions of the internal shielding structures do not deviate from the technical concept of this application and fall within the protection scope of this application. However, it should be noted that for any one internal shielding structure, at least the following conditions need to be met: there is at least one second conductive structure in the internal shielding structure, and / or at least one end of the internal shielding structure is horizontally connected to the external shielding structure with a first conductive structure, so as to ensure that the electromagnetic waves absorbed in the internal shielding layer material are led to a low-potential circuit or a ground wire to achieve the electromagnetic shielding effect.

[0122] The embodiment of this application also provides a manufacturing method for a third semiconductor storage structure, including:

[0123] Step S10: Deposit and etch the magnetic tunnel junction film stack to simultaneously form multiple magnetic tunnel junctions, an external shielding layer, and an internal shielding layer. The external shielding layer is located on the outer periphery of the data storage structure to form an external shielding structure. The internal shielding layer is formed at the intervals between at least two magnetic tunnel junctions and is connected to the external shielding structure at least at one end. There are multiple magnetic tunnel junctions;

[0124] Step S30: Form at least one void in the internal shielding layer, and form a second conductive structure in the void. The internal shielding layer and the second conductive structure are horizontally connected to form an internal shielding structure, and there is a potential difference between the two ends of the second conductive structure.

[0125] The difference between the manufacturing method for the third semiconductor storage structure provided by the embodiment of this application and the manufacturing method for the second semiconductor storage structure is that: the external shielding structure is a closed figure formed by horizontally connecting the external shielding layers; the internal shielding structure is formed by horizontally connecting the internal shielding layer and at least one second conductive structure, and there is a potential difference between the two ends of the second conductive structure.

[0126] The semiconductor storage structure finally formed by the manufacturing method of this embodiment can be referred to Figures 7 to 9The external shielding structure 30 is formed by the external shielding layer 31, and the internal shielding layer 51 and the conductive magnetic materials in the external shielding layer 31 are interconnected to form a conductive whole. The potential inside the conductive whole is equal. At this time, the two ends of the second conductive structure 52 have a potential difference, such as connecting one end to a low-potential circuit or grounding. The external shielding structure 30 and the internal shielding structure 50 form an effective Faraday cage, which can shield the external electromagnetic field, effectively isolate the external environment and the electromagnetic interference generated by the magnetic storage device in the adjacent area during high-frequency reading and writing, and reduce the reading and writing error rate.

[0127] The embodiment of the present application also provides a fourth method for manufacturing a semiconductor storage structure, which is different from the first method for manufacturing a semiconductor storage structure in that the data storage unit is different, and step S10 is specifically as follows:

[0128] S101: forming a bottom electrode, and sequentially depositing a magnetic tunnel junction film stack on the bottom electrode;

[0129] S102: etching the magnetic tunnel junction film stack to simultaneously form at least one magnetic tunnel junction and an external shielding layer, wherein the external shielding layer is formed on the periphery of the magnetic tunnel junction.

[0130] The semiconductor storage structure finally formed in this embodiment refers to Figure 11 As shown, compared Figure 2 In the data storage structure formed by the manufacturing method of this embodiment, a top electrode 22 and a bottom electrode 40 are respectively arranged above and below the magnetic tunnel junction 21, and the heavy metal layer 24 is not involved. The second data storage unit in this embodiment includes: a magnetic tunnel junction 21, a top electrode 22 and a bottom electrode 40. The bottom electrode 40 is correspondingly arranged below the magnetic tunnel junction 21, so that the write current and the read current flow between the top electrode 22-magnetic tunnel junction 21-bottom electrode 40, forming a write path and a read path, so as to realize data writing and data reading of the magnetic tunnel junction 21.

[0131] Specifically, when the write current flows through the top electrode 22 and the bottom electrode 40 through the magnetic tunnel junction 21, the write current is polarized to form a spin-polarized current, and the spin electrons transfer the spin momentum to the magnetic moment of the free layer, causing the magnetic moment of the free layer to change direction. The direction of the write current is different, and the direction of the magnetic moment of the free layer is also different, which is parallel or anti-parallel to the magnetic moment direction of the reference layer. The magnetic tunnel junction 21 exhibits a low resistance state or a high resistance state to store data "0" or "1". A read current is applied to the magnetic tunnel junction 21 through the top electrode 22 and the bottom electrode 40 to obtain the resistance state of the magnetic tunnel junction 21 to obtain a specific storage value.

[0132] It can be understood that the data storage units in the manufacturing methods of the second and third semiconductor storage structures provided by the embodiments of the present application can also be set using the second data storage unit and similar data storage unit structures. The manufacturing methods of the external shielding structure, internal shielding structure, etc. in the manufacturing method of the semiconductor storage structure are the same as those of the external shielding structure, internal shielding structure, etc. in the manufacturing methods of the second and third semiconductor storage structures. The specific manufacturing methods will not be described in detail.

[0133] The embodiments or implementation manners in this specification are described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other. The descriptions with reference to terms such as "one implementation manner", "some implementation manners", "illustrative implementation manner", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the implementation manner or example are included in at least one implementation manner or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same implementation manner or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more implementation manners or examples.

[0134] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A semiconductor storage structure, characterized in that: At least: A data storage structure and an external shielding structure disposed on the periphery of the data storage structure; The data storage structure includes at least one magnetic tunnel junction; The external shielding structure is formed by horizontally connecting the external shielding layer and at least one first conductive structure to form a closed figure, and the first conductive structure has a potential difference at both ends; The magnetic tunnel junction and the external shielding layer are both obtained by synchronously etching a magnetic tunnel junction film stack.

2. The semiconductor storage structure according to claim 1, characterized in that: A plurality of magnetic tunnel junctions and an internal shielding structure are arranged in the data storage structure; The internal shielding structure is disposed at a distance between at least two of the magnetic tunnel junctions, and at least one end thereof is connected to the external shielding structure; The internal shielding structure at least includes an internal shielding layer, and the magnetic tunnel junction, the external shielding layer and the internal shielding layer are all obtained by synchronously etching the magnetic tunnel junction film stack.

3. The semiconductor storage structure according to claim 2, characterized in that: The internal shielding structure is formed by horizontally connecting the internal shielding layer and at least one second conductive structure, and two ends of the second conductive structure have a potential difference.

4. The semiconductor storage structure according to claim 1, characterized in that: A plurality of magnetic tunnel junctions and an internal shielding structure are arranged in the data storage structure; The internal shielding structure is disposed at a distance between at least two of the magnetic tunnel junctions and is not connected to the external shielding structure; The internal shielding structure is formed by horizontally connecting the internal shielding layer and at least one second conductive structure, and the second conductive structure has a potential difference at both ends; The magnetic tunnel junction, the external shielding layer and the internal shielding layer are all obtained by synchronously etching the magnetic tunnel junction film stack.

5. The semiconductor storage structure according to any one of claims 1 to 4, characterized in that: The data storage structure further includes a third conductive structure disposed beside the magnetic tunnel junction, the third conductive structure being connected to an external circuit to form a read path; The third conductive structure is formed simultaneously with the first conductive structure.

6. A semiconductor storage structure, characterized in that: At least: Data storage structure and shielding structure; The data storage structure includes a plurality of magnetic tunnel junctions; The shielding structure comprises an external shielding structure and an internal shielding structure, wherein the external shielding structure is arranged at the periphery of the data storage structure, and the internal shielding structure is arranged at the interval between at least two of the magnetic tunnel junctions, and at least one end of the internal shielding structure is connected to the external shielding structure; The external shielding structure is formed by an external shielding layer, the internal shielding structure is formed by horizontally connecting the internal shielding layer and at least one second conductive structure, and the second conductive structure has a potential difference at both ends; The magnetic tunnel junction, the external shielding layer and the internal shielding layer are all obtained by synchronously etching a magnetic tunnel junction film stack.

7. The semiconductor storage structure according to claim 1 or 6, characterized in that: The magnetic tunnel junction and the heavy metal layer correspondingly arranged under the external shielding layer are formed synchronously.

8. The semiconductor storage structure according to claim 1 or 6, characterized in that: The external shielding layer is a ring-shaped structure, and the minimum distance between two opposite side walls thereof is not less than the minimum width of the magnetic tunnel junction.

9. A method for manufacturing a semiconductor storage structure, characterized in that: The steps include: Depositing and etching a magnetic tunnel junction film stack to simultaneously form a magnetic tunnel junction and an external shielding layer, wherein the external shielding layer is formed at the periphery of the magnetic tunnel junction, and the magnetic tunnel junction has at least one; At least one gap is formed in the outer shielding layer, a first conductive structure is formed in the gap, the outer shielding layer and the first conductive structure are horizontally connected to form an outer shielding structure, and the outer shielding structure is a closed figure; Two ends of the first conductive structure have a potential difference.

10. The manufacturing method according to claim 9, characterized in that: Etching the magnetic tunnel junction film stack to simultaneously form a plurality of the magnetic tunnel junctions, the outer shielding layer and the inner shielding layer; The internal shielding layer is formed at a distance between at least two of the magnetic tunnel junctions to form an internal shielding structure, and at least one end of the internal shielding structure is connected to the external shielding structure; or, Etching the magnetic tunnel junction film stack to simultaneously form a plurality of the magnetic tunnel junctions, the outer shielding layer and the inner shielding layer; The internal shielding layer is formed at a distance between at least two of the magnetic tunnel junctions to form an internal shielding structure, and at least one end of the internal shielding structure is connected to the external shielding structure; forming at least one gap in the internal shielding layer, forming a second conductive structure in the gap, and the internal shielding layer and the second conductive structure are horizontally connected to form an internal shielding structure; Two ends of the second conductive structure have a potential difference.

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