Semiconductor storage structure and manufacturing method thereof

Abstract

The invention provides a semiconductor storage structure and a manufacturing method thereof, relates to the technical field of semiconductors, and is used for solving the problem of process step and cost increase caused by additional arrangement of a magnetic shielding layer for realizing an electromagnetic shielding function in the prior art. The semiconductor storage structure comprises a data storage structure and an external shielding structure arranged on the periphery of the data storage structure, the data storage structure comprises at least one magnetic tunnel junction; the external shielding structure is a closed pattern formed by horizontally connecting an external shielding layer and at least one first conductive structure, and potential difference exists between two ends of the first conductive structure; the magnetic tunnel junction and the external shielding layer are both obtained based on synchronous etching of a magnetic tunnel junction film stack. By arranging the external shielding structure and forming an equipotential body, electromagnetic shielding of the data storage structure is effectively realized; and the magnetic tunnel junction and the external shielding layer are obtained based on synchronous etching of the magnetic tunnel junction film stack, so that additional process steps are not needed, and the manufacturing cost is effectively reduced.

Description

Technical Field

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

[0002] The basic storage unit of magnetic random access memory (MRAM) is magnetic tunnel junction (MTJ). The core structure of MTJ is a sandwich structure of reference layer / barrier layer / free layer, in which the magnetization direction of the reference layer remains unchanged, and the magnetization direction of the free layer can be changed by external stimulation to achieve data writing. When the magnetization direction of the free layer is parallel or anti-parallel to 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 reading and writing process of magnetic storage, the electromagnetic fields in the external environment (such as power supply, radio waves, etc.) and the electromagnetic fields generated when adjacent devices are reading and writing will cause certain interference to the storage devices, especially when the density of storage devices increases, the distance between storage devices becomes shorter, or the same adjacent storage device is repeatedly read and written at a high frequency, which will cause such electromagnetic influences to intensify, causing the reading and writing error rate of the storage devices to increase.

[0004] To solve the above problems, the existing technology usually involves an additional magnetic shielding layer on the outside of the magnetic tunnel junction or the memory chip to reduce electromagnetic interference from adjacent devices and external electromagnetic interference, thereby reducing the read and write error rate. However, this method requires adding a preparation step of the magnetic shielding layer in addition to the manufacturing process of the magnetic memory, which increases additional process and manufacturing costs. Summary of the invention

[0005] In order to solve the above problems, an embodiment of the present application provides a semiconductor storage 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, the present application provides a semiconductor storage structure, comprising at least: A data storage structure and an external shielding structure arranged 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 an external shielding layer and at least one first conductive structure to form a closed figure, and there is a potential difference at both 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.

[0007] In some possible examples, a plurality of magnetic tunnel junctions and an internal shielding structure are provided in the data storage structure; the internal shielding structure is provided at the interval between at least two magnetic tunnel junctions, and at least one end is connected to the external shielding structure; the internal shielding structure includes at least an internal shielding layer, and 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.

[0008] In some possible examples, 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.

[0009] In some possible examples, multiple magnetic tunnel junctions and an internal shielding structure are arranged in the data storage structure; the internal shielding structure is arranged at the interval between at least two magnetic tunnel junctions and is not connected to the 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 at both ends of the second conductive structure; 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.

[0010] In some possible examples, 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 synchronously with the first conductive structure.

[0011] In some possible examples, the magnetic tunnel junction and the heavy metal layer correspondingly disposed under the external shielding layer are formed simultaneously.

[0012] In some possible examples, the outer 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.

[0013] According to some embodiments, the present application also provides a semiconductor storage structure, comprising at least: 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 arranged at the periphery of the data storage structure, the internal shielding structure is arranged at the interval between at least two magnetic tunnel junctions, and at least one end 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 two ends of the second conductive structure have a potential difference; 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.

[0014] In some possible examples, the magnetic tunnel junction and the heavy metal layer correspondingly disposed under the external shielding layer are formed simultaneously.

[0015] In some possible examples, the outer 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.

[0016] The semiconductor storage structure provided by the embodiment of the present application has at least the following advantages: The semiconductor storage structure in the embodiment of the present application is provided with an external shielding structure on the periphery of the data storage structure. The shielding structure is a closed figure formed by horizontally connecting the external shielding layer and at least one first conductive structure, and the two ends of the first conductive structure have a potential difference, which can realize the electromagnetic shielding of the data storage structure, so as to effectively isolate the electromagnetic interference of adjacent devices and external electromagnetic interference, and reduce the read and write error rate. At the same time, the magnetic tunnel junction in the external shielding structure and the data storage structure are obtained by synchronous etching based on the same magnetic tunnel junction film stack, without the need to add new magnetic shielding materials and corresponding manufacturing steps, which simplifies the manufacturing process and reduces the manufacturing cost.

[0017] According to some embodiments, the present application provides a method for manufacturing a semiconductor storage structure, the steps comprising: A magnetic tunnel junction film stack is deposited and etched 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 there is at least one magnetic tunnel junction; at least one gap is formed in the external shielding layer, and a first conductive structure is formed in the gap; the external shielding layer is horizontally connected to the first conductive structure to form an external shielding structure, and the external shielding structure is a closed figure; and there is a potential difference at both ends of the first conductive structure.

[0018] In some possible examples, a magnetic tunnel junction film stack is etched to simultaneously form a plurality of magnetic tunnel junctions, an external shielding layer, and an internal shielding layer; the internal shielding layer is formed at a distance 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; Alternatively, a magnetic tunnel junction film stack is etched to simultaneously form multiple 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 constitute an internal shielding structure, and at least one end of the internal shielding structure is connected to the external shielding structure; at least one gap is formed in the internal shielding layer, a second conductive structure is formed in the gap, and the internal shielding layer is horizontally connected to the second conductive structure to form the internal shielding structure; and a potential difference exists at both ends of the second conductive structure.

[0019] The method for manufacturing a semiconductor storage structure in the embodiment of the present application has at least the following advantages: In the manufacturing method of the semiconductor storage structure in the embodiment of the present application, an external shielding structure is arranged on the periphery of the data storage structure. The shielding structure is a closed figure formed by horizontally connecting the external shielding layer and at least one first conductive structure, and the two ends of the first conductive structure have a potential difference, 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 reduce the read and write error rate. At the same time, the magnetic tunnel junction in the external shielding structure and the data storage structure are obtained by synchronous etching based on the same magnetic tunnel junction film stack, without the need to add new magnetic shielding materials and corresponding manufacturing steps, which simplifies the manufacturing process and reduces the manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a top view of a first semiconductor storage structure in an embodiment of the present application.

[0021] Figure 2 It is a schematic cross-sectional view of the first semiconductor storage structure along the AA′ direction in one embodiment of the present application.

[0022] Figure 3 It is a top view of a second semiconductor storage structure in an embodiment of the present application.

[0023] Figure 4 It is a schematic cross-sectional view of a second semiconductor storage structure along the BB' direction in an embodiment of the present application.

[0024] Figure 5 It is a top view of a third semiconductor storage structure in an embodiment of the present application.

[0025] Figure 6 It is a schematic cross-sectional view of a third semiconductor storage structure along the BB' direction in an embodiment of the present application.

[0026] Figure 7 It is a top view of a fourth semiconductor storage structure in an embodiment of the present application.

[0027] Figure 8 It is a schematic cross-sectional view along the AA′ direction of the fourth semiconductor storage structure in one embodiment of the present application.

[0028] Fig. 9 It is a schematic cross-sectional view of a fifth semiconductor storage structure along the BB' direction in an embodiment of the present application.

[0029] Fig.10 It is a top view of a fifth semiconductor storage structure in an embodiment of the present application.

[0030] Fig.11 It is a schematic cross-sectional view of a fifth semiconductor storage structure along the AA′ direction in an embodiment of the present application.

[0031] Fig.12 This is a flow chart of a method for manufacturing a first semiconductor storage structure in an embodiment of the present application.

[0032] Fig.13 This is a top view after etching the outer shielding layer to form a gap in the manufacturing method of the first semiconductor storage structure in one embodiment of the present application.

[0033] Fig.14 It is a schematic cross-sectional view along the AA′ direction after etching the outer shielding layer to form a gap in the manufacturing method of the first semiconductor storage structure in one embodiment of the present application.

[0034] Description of reference numerals: 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-gap; 70-interconnection through hole. DETAILED DESCRIPTION

[0035] During the reading and writing process of magnetic storage, the electromagnetic fields in the external environment (such as power supply, radio waves, etc.) and the electromagnetic fields of adjacent devices will cause certain interference to the storage devices, especially when the density of storage devices increases, the distance between storage devices becomes shorter, or the same adjacent storage device is repeatedly read and written at a high frequency, which will cause such electromagnetic influences to intensify and increase the reading and writing error rate of the storage devices.

[0036] In order to solve the above problems, the existing technology usually coats an additional magnetic shielding layer on the outside of the magnetic tunnel junction or the memory chip to reduce electromagnetic interference from adjacent devices and external magnetic field interference, thereby reducing the read and write error rate. However, this method requires adding a manufacturing step of the magnetic shielding layer in addition to the manufacturing process of the magnetic memory, which increases additional process and manufacturing costs.

[0037] The semiconductor storage structure in the embodiment of the present application is provided with an external shielding structure on the periphery of the data storage structure. The shielding structure is a closed figure formed by horizontally connecting the external shielding layer and at least one first conductive structure, and the two ends of the first conductive structure have a potential difference, which can realize the electromagnetic shielding of the data storage structure, so as to effectively isolate the electromagnetic interference of adjacent devices and external electromagnetic interference, and reduce the read and write error rate. At the same time, the magnetic tunnel junction in the external shielding structure and the data storage structure are obtained by synchronous etching based on the same magnetic tunnel junction film stack, without the need to add new magnetic shielding materials and corresponding manufacturing steps, which simplifies the manufacturing process and reduces the manufacturing cost.

[0038] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described in this application are only some embodiments of the present application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of this application.

[0039] The present application provides a semiconductor storage structure, which at least includes: A data storage structure and an external shielding structure arranged 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 an external shielding layer and at least one first conductive structure to form a closed figure, and there is a potential difference at both 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.

[0040] refer to Figure 1 and Figure 2 , which is a schematic diagram of the first semiconductor storage structure 10 provided in an embodiment of the present application, at least includes: a data storage structure and an external shielding structure 30 arranged on the periphery of the data storage structure; the data storage structure has a plurality of magnetic tunnel junctions 21; the external shielding structure 30 is horizontally connected by an external shielding layer 31 and at least one first conductive structure 32 to form a closed figure, and there is a potential difference at both ends of the first conductive structure 32; the magnetic tunnel junction 21 and the external shielding layer 31 are both obtained by synchronous etching of the magnetic tunnel junction film stack.

[0041] In the semiconductor storage structure 10 provided in this embodiment, the magnetic tunnel junction 21 is the core component of the data storage structure, which 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 material of the free layer and the reference layer can be a ferromagnetic material, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc. and their alloys, or a ferrimagnetic material; the free layer and the reference layer can be a single layer or a multi-layer 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 also be provided in the magnetic tunnel junction 21, which is located on the side of the reference layer away from the barrier layer to fix the magnetization direction of the reference layer.

[0042] The shape of the magnetic tunnel junction 21 is elliptical, and may also be circular, triangular, rhombus, etc. Figure 1 The top view in FIG. 1 is only a schematic diagram of the relative position of the magnetic tunnel junction 21 and the external shielding structure 30 , and does not impose any limitation on the shape of the magnetic tunnel junction 21 .

[0043] Multiple magnetic tunnel junctions 21 can be set, and multiple magnetic tunnel junctions 21 can be arranged in an array or arranged in different areas according to storage requirements, functions, etc.; only one magnetic tunnel junction 21 can also be set. Technical personnel in this field can flexibly set the number and arrangement of magnetic tunnel junctions 21 according to their actual needs, and no limitation is made here.

[0044] In the data storage structure, each magnetic tunnel junction 21 is provided with a one-to-one corresponding write path and a read path. For the convenience of description, the one-to-one corresponding write path and read path of each magnetic tunnel junction 21 are named as data storage units. Figure 2 What is shown is the first data storage unit in this embodiment, including: a magnetic tunnel junction 21, a top electrode 22, a heavy metal layer 24 and a bottom electrode 40, the bottom electrode 40 is arranged at both ends of the heavy metal layer 24, so that the write current flows through the heavy metal layer 24, forming a write path, thereby realizing data writing of the magnetic tunnel junction 21; the top electrode 22 and any bottom electrode 40 under the heavy metal layer 24 form a read path, thereby realizing data reading of the magnetic tunnel junction 21.

[0045] Specifically, in the semiconductor storage structure 10 of the present embodiment, the free layer of the magnetic tunnel junction 21 is arranged 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. The direction of the write current is different, and the direction of the magnetic moment of the free layer is also different, so that it appears parallel or anti-parallel to the magnetic moment direction of the reference layer, and the magnetic tunnel junction 21 appears in a low resistance state or a high resistance state to store 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.

[0046] The heavy metal layer 24 is a conductive material with a strong spin-orbit coupling effect, including single substances such as platinum, tantalum, tungsten, and alloys thereof, and its structure can be a single layer or a multi-layer composite structure.

[0047] Since the heavy metal layer 24 is arranged below the magnetic tunnel junction 21, 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 arranged below the external shielding structure 30. It is worth noting 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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, and the electromagnetic flux lines concentrated in the external shielding layer 31 will increase. Since the degree of absorption of electromagnetic waves by materials is limited by various factors such as the properties of the materials (electrical conductivity, magnetic 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 set in the external shielding structure 30. Preferably, the multiple first conductive structures 32 are evenly arranged at equal distances, so that the electromagnetic waves absorbed by the materials in the external shielding layer 31 can be timely guided to the low-potential circuit or the ground wire through the first conductive structure 32, so as to further improve the electromagnetic shielding effect.

[0052] The outer shielding layer 31 is an annular 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. Figure 1 , the minimum distance w between two opposite side walls of the outer shielding layer 31 1 Should not be less than the minimum width w of the magnetic tunnel junction 21 2 , to ensure that the external shielding layer 31 can effectively isolate electromagnetic interference; in addition, the smaller size of the external shielding layer 31 will increase the difficulty and cost of the manufacturing process, such as requiring a high-precision etching method and a high-resolution lithography machine, etc. In this embodiment, the minimum distance w between the two opposite side walls of the external shielding layer 31 is 1 Not less than the minimum width w of the magnetic tunnel junction 21 2 , no high-precision lithography and etching technology is required, which reduces the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0053] Continue to refer 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 simultaneously, in order 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.

[0054] A bottom electrode 40 may be disposed under the first conductive structure 32 to facilitate connection with a low potential circuit or ground wire below; a bottom electrode 40 may also be disposed under the third conductive structure 23 to facilitate connection with a logic circuit below. It is worth noting that the bottom electrodes 40 under the magnetic tunnel junction 21, the first conductive structure 32, and the third conductive structure 23 are not electrically connected to each other.

[0055] Furthermore, the bottom electrode 40 is arranged in the substrate (not shown in the figure), and 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; a logic circuit and a low-potential circuit or ground wire are also arranged in the substrate, and the logic circuit is electrically connected to the third conductive structure 23, and the low-potential circuit or ground wire is connected to the first conductive structure 32, which can be selected according to actual manufacturing requirements.

[0056] The present application also provides a second semiconductor storage structure, see Figure 3 and Figure 4 The semiconductor storage structure 10 is different from the first semiconductor storage structure mainly in that: the data storage structure includes multiple magnetic tunnel junctions 21 and an internal shielding structure 50; the internal shielding structure 50 is arranged at the interval 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 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.

[0057] In this embodiment, the internal shielding structure 50 is arranged at the interval between at least two magnetic tunnel junctions 21, that is, the internal shielding structure 50 is arranged at the interval between at least two first data storage units, such as, at the interval between two of a plurality of first data storage units, at the interval between two adjacent columns of first data storage units arranged in a matrix, or at the interval between every two first data storage units, etc., and can be flexibly arranged according to actual needs.

[0058] 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. It can be understood that the magnetic tunnel junction film stack structure and materials forming the internal shielding layer 51, the external shielding layer 31 and the magnetic tunnel junction 21 are exactly the same. For example, taking the magnetic tunnel junction film stack including the free layer / barrier layer / reference layer from bottom to top as an example, the external shielding layer 31, the internal shielding layer 51 and the magnetic tunnel junction 21 formed by synchronous etching of the magnetic tunnel junction film stack also include the above-mentioned free layer / barrier layer / reference layer, and the three are consistent in terms of film stacking method, film material and film thickness. In addition, the manufacturing process of the internal shielding layer 51, the external shielding layer 31 and the magnetic tunnel junction 21 is completely synchronized, and the internal shielding layer 51 and the external shielding layer 31 can be obtained at the same time through a single manufacturing process of the magnetic tunnel junction 21, which simplifies the process and reduces the production cost.

[0059] At least one end of the inner shielding structure 50 is connected to the outer shielding structure 30, or both ends of the inner shielding structure 50 are connected to the outer shielding structure 30. 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.

[0060] Continue to refer Figure 3 The minimum distance w between two opposite side walls of the inner shielding layer 51 is 3 Should not be less than the minimum width w of the magnetic tunnel junction 21 2 , 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 requiring a high-precision etching method and a high-resolution lithography machine, etc. In this embodiment, the minimum distance w between the two opposite side walls of the internal shielding layer 51 is 3 Not less than the minimum width w of the magnetic tunnel junction 21 2 , no high-precision lithography and etching technology is required, which reduces the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] The present application also provides a fifth semiconductor storage structure, see Fig.10 and Fig.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.

[0071] contrast Figure 2 and Fig.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. Fig.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.

[0072] 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.

[0073] It can be understood that the data storage unit in the second to fourth semiconductor storage structures provided in the embodiments of the present application can also be set up using the second data storage unit and similar data storage unit structures, and the external shielding structure, internal shielding structure, etc. in the resulting semiconductor storage structure are the same as the external shielding structure, internal shielding structure, etc. in the second to fourth semiconductor storage structures, and will not be described in detail.

[0074] On the other hand, the present application also provides a method for manufacturing a semiconductor storage structure. The flowchart of the first manufacturing method is shown in FIG. Fig.12 , including the following steps: Step S10: depositing and etching a magnetic tunnel junction film stack, and simultaneously forming a magnetic tunnel junction and an external shielding layer, wherein the external shielding layer is formed on the periphery of the magnetic tunnel junction, and there is at least one magnetic tunnel junction; Step S20: forming at least one gap in the external shielding layer, forming 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, the external shielding structure is a closed figure; and there is a potential difference at both ends of the first conductive structure.

[0075] Figure 1 and Figure 2 The top view and the cross-sectional view along the AA' direction of the semiconductor storage structure finally formed by the first manufacturing method of the embodiment of the present application are shown in FIG. S101: forming a bottom electrode, depositing a heavy metal layer and a magnetic tunnel junction film stack in sequence above the bottom electrode, and the bottom electrode is formed at both ends of the heavy metal layer; 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; S103: etching 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.

[0076] The deposited heavy metal layer is a conductive material with a strong spin-orbit coupling effect, including platinum, tantalum, tungsten and other elements and their alloys, and its structure can be a single layer or a multi-layer composite structure; the heavy metal layer is deposited above the magnetic tunnel junction stack, adjacent to the free layer, so as to utilize the spin-orbit effect to flip the magnetic moment direction of the free layer and realize the writing of storage data.

[0077] 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 free layer and the reference layer can be made of ferromagnetic materials, such as cobalt, iron, boron, nickel, ruthenium, iridium, platinum, etc., or ferrimagnetic materials; the free layer and the reference layer can be a single layer or a composite film layer; the barrier layer is made of insulating materials, such as magnesium oxide, aluminum oxide, silicon oxide, etc. In addition, a pinning layer can be provided 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.

[0078] The bottom electrode can be formed in the substrate (not shown in the figure), and a magnetic tunnel junction stack is deposited above the substrate. The shape of the substrate can be circular, rectangular, diamond and other shapes, which can be selected according to actual manufacturing needs; the material of the substrate can be semiconductor materials, such as silicon, silicon carbide, gallium nitride, aluminum nitride, etc., or insulating materials, such as germanium; logic circuits and low-potential circuits or ground lines are also provided in the substrate.

[0079] For step S102 , the magnetic tunnel junction film stack is patterned and etched to simultaneously form a magnetic tunnel junction and an external shielding layer, wherein the external shielding layer is formed on the periphery of the magnetic tunnel junction.

[0080] See also Fig.13 and Fig.14 The magnetic tunnel junction 21 formed is used for data storage, and its shape can be elliptical, circular, triangular, diamond, etc. Fig.13 The top view in FIG. 1 is only a schematic diagram of the magnetic tunnel junction 21 , and does not impose any limitation on the shape of the magnetic tunnel junction 21 .

[0081] After etching the magnetic tunnel junction film stack, multiple magnetic tunnel junctions 21 can be formed at the same time. The multiple magnetic tunnel junctions 21 are arranged in an array or arranged in different areas according to storage requirements, functions, etc.; only one magnetic tunnel junction 21 can be formed. Technical personnel in this field can flexibly set the number and arrangement of the magnetic tunnel junctions 21 according to their actual needs, and there is no limitation here.

[0082] The outer shielding layer 31 is an annular 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. Fig.13 , the minimum distance w between two opposite side walls of the outer shielding layer 31 1 Should not be less than the minimum width w of the magnetic tunnel junction 21 2, to ensure that the external shielding layer 31 can effectively isolate electromagnetic interference; in addition, the smaller size of the external shielding layer 31 will increase the difficulty and cost of the manufacturing process, such as requiring a high-precision etching method and a high-resolution lithography machine, etc. In this embodiment, the minimum distance w between the two opposite side walls of the external shielding layer 31 is 1 Not less than the minimum width w of the magnetic tunnel junction 21 2 , no high-precision lithography and etching technology is required, which reduces the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0083] The external shielding layer 31 and the magnetic tunnel junction 21 are both obtained by synchronous etching of the magnetic tunnel junction film stack. For example, taking the magnetic tunnel junction film stack including the 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 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.

[0084] In step S103 , the heavy metal layer is etched to cut off the electrical connection between the magnetic tunnel junction and the heavy metal layer below the external shielding structure.

[0085] See also Fig.14 Since the heavy metal layer 24 is formed below the magnetic tunnel junction 21, 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, the heavy metal layer 24 is also synchronously formed below the external shielding structure 30. To avoid a short circuit in 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.

[0086] For step S20, see Fig.13 and Fig.14 , the outer shielding layer 31 is etched, at least one gap 60 is formed in the annular outer shielding layer 31, and a conductive material is deposited in the gap 60 to form a first conductive structure. The gap 60 can be formed by etching the outer shielding layer 31 again after forming the magnetic tunnel junction 21; or it can be formed in the outer shielding layer 31 synchronously 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 outer shielding layer 31, so as to ensure that after the conductive material is filled in the gap 60 to form the first conductive structure, each film layer in the outer shielding layer 31 can be horizontally connected to the first conductive structure.

[0087] Continue to refer 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 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 material layers in the external shielding layer 31 are conductive and are horizontally connected to the first conductive structure 32 to form a conductive whole, and the potential inside the external shielding structure 30 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 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, 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.

[0088] 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, and the electromagnetic flux lines concentrated in the external shielding layer 31 will increase. Since the degree of absorption of electromagnetic waves by materials is limited by various factors such as the properties of the materials (electrical conductivity, magnetic 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 set in the external shielding structure 30. Preferably, the multiple first conductive structures 32 are evenly arranged at equal distances, so as to timely guide 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.

[0089] A top electrode 22 is also formed above the magnetic tunnel junction 21. The top electrode 22 and the bottom electrode 40 are both made of conductive materials, such as metal or alloy, and the materials of the two can be the same or different, and are both used for 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 write current flows through the heavy metal layer 24 to form a write path to achieve data writing of the magnetic tunnel junction 21; the top electrode 22 and any bottom electrode 40 below the heavy metal layer 24 form a read path to achieve data reading of the magnetic tunnel junction 21.

[0090] For the convenience of description, the write path and the read path corresponding to each magnetic tunnel junction 21 are named as data storage units. Figure 2The first data storage unit in the manufacturing method of this embodiment is shown, 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 arranged 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, inducing 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, so that it is parallel or anti-parallel to the magnetic moment direction of the reference layer, and the magnetic tunnel junction 21 is low-resistance or high-resistance to store data "0" or "1". When a read current is applied 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.

[0091] Furthermore, in order to reduce the logic circuit area on the top of the magnetic tunnel junction 21 in the data storage unit and increase the integration of the functional modules of the memory chip, a third conductive structure can be provided beside the magnetic tunnel junction 21. Figure 1 and Figure 2 As shown, by electrically connecting the top electrode 22 and the third conductive structure 23 (the connection relationship is not shown in the figure), the reading 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 reading path. The third conductive structure 23 and the first conductive structure 32 are both conductive materials, such as metal or alloy.

[0092] The third conductive structure 23 and the first conductive structure 32 can be formed simultaneously. Fig.13 and Fig.14 The specific process is as follows: after etching to form the magnetic tunnel junction 21, an interconnection through hole 70 is formed next to the magnetic tunnel junction 21, and when a conductive material is deposited in the gap 60 to form a first conductive structure, a conductive material is simultaneously deposited in the interconnection through hole 70 to form a third conductive structure.

[0093] Continue to refer 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 simultaneously, in order 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.

[0094] A bottom electrode 40 is also formed under the first conductive structure 32, and 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 to the low potential circuit or ground wire below; a bottom electrode 40 can also be formed under the third conductive structure 23 to facilitate the connection of the third conductive structure 23 with the logic circuit below, which is not limited here. It is worth noting that the bottom electrode 40 under the magnetic tunnel junction 21, the bottom electrode 40 under the first conductive structure 32, and the bottom electrode 40 under the third conductive structure 23 are not electrically connected to each other.

[0095] This embodiment also provides a second method for manufacturing a semiconductor storage structure. Different from the first method, the method of the present embodiment further includes forming an internal shielding structure in the data storage structure. Step S102 specifically includes: A magnetic tunnel junction film stack is deposited and etched to simultaneously form a plurality of magnetic tunnel junctions, an external shielding layer and an internal shielding layer. The external shielding layer is formed at the periphery of the data storage structure; and the internal shielding layer is formed at the interval between at least two magnetic tunnel junctions.

[0096] In the manufacturing method of the present embodiment, the internal shielding structure is arranged at the interval between at least two magnetic tunnel junctions, that is, the internal shielding structure is arranged at the interval between at least two first data storage units, such as, at the interval between two of a plurality of first data storage units, at the interval between two adjacent columns of first data storage units arranged in a matrix, or at the interval between every two first data storage units, etc., and can be flexibly arranged according to actual needs.

[0097] The magnetic tunnel junction, the external shielding layer and the internal shielding layer are all obtained by synchronous etching of the magnetic tunnel junction film stack. For example, taking the magnetic tunnel junction film stack including the free layer / barrier layer / reference layer from bottom to top as an example, the external shielding layer, the internal shielding layer and the magnetic tunnel junction formed by synchronous etching of the magnetic tunnel junction film stack also include the above-mentioned free layer / barrier layer / reference layer, and the three are consistent in terms of film stacking method, film material and film thickness. In addition, the manufacturing process of the internal shielding layer, the external shielding layer and the magnetic tunnel junction is completely synchronized. The internal shielding layer and the external shielding layer can be obtained at the same time through a single manufacturing process of the magnetic tunnel junction, which simplifies the process and reduces the production cost.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] Continue reading Figure 3 The minimum distance w between two opposite side walls of the inner shielding layer 51 is 3 Should not be less than the minimum width w of the magnetic tunnel junction 2 , 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 requiring a high-precision etching method and a high-resolution lithography machine, etc. In this embodiment, the minimum distance w between the two opposite side walls of the internal shielding layer 51 is 3 Not less than the minimum width w of the magnetic tunnel junction 2 , no high-precision lithography and etching technology is required, which reduces the process difficulty and manufacturing cost while ensuring the electromagnetic shielding effect.

[0102] The conductive magnetic material layers in the internal shielding layer 51 and 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.

[0103] In order to further enhance the electromagnetic shielding effect, at least one second conductive structure may also be formed inside the internal shielding structure. The specific steps include: Step S30: etching the internal shielding layer to form at least one gap in the internal shielding layer, depositing a conductive material in the gap to form a second conductive structure, wherein the internal shielding layer and the second conductive structure are horizontally connected to form an internal shielding structure, and a potential difference exists at both ends of the second conductive structure.

[0104] Continue reading Figure 3 and Figure 4 By connecting one end of the second conductive structure 52 to a low potential circuit or ground, the second conductive structure 52 is combined with the first conductive structure 32 to timely guide 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, thereby enhancing the electromagnetic shielding effect. 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 simultaneously from the same material.

[0105] In addition, see Figure 5 and Figure 6 In the semiconductor storage structure 10 shown, the internal shielding structure 50 may not be connected to the external shielding structure 30. Therefore, it is necessary to form at least one second conductive structure 52 in the internal shielding structure 50 to timely 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.

[0106] 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 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 those skilled in the art according to actual needs do not deviate from the technical concept of the present application and fall within the scope of protection of the present 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 an external shielding structure having a first conductive structure, so as to ensure that the electromagnetic waves absorbed in the internal shielding layer material are guided out to a low-potential circuit or ground wire to achieve an electromagnetic shielding effect.

[0107] The present application also provides a third method for manufacturing a semiconductor storage structure, including: Step S10: depositing and etching a magnetic tunnel junction film stack, and simultaneously forming a plurality of magnetic tunnel junctions, an external shielding layer, and an internal shielding layer, wherein the external shielding layer is located at the periphery of the data storage structure, forming an external shielding structure, and the internal shielding layer is formed at the interval between at least two magnetic tunnel junctions, and at least one end is connected to the external shielding structure, and there are a plurality of magnetic tunnel junctions; Step S30: forming at least one gap in the internal shielding layer, forming 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, and a potential difference exists at both ends of the second conductive structure.

[0108] The difference between the third semiconductor storage structure manufacturing method provided in the embodiment of the present application and the second semiconductor storage structure manufacturing method is that: the external shielding structure is a closed figure formed by horizontally connecting the 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 two ends of the second conductive structure have a potential difference.

[0109] 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.

[0110] 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: S101: forming a bottom electrode, and sequentially depositing a magnetic tunnel junction film stack on the bottom electrode; 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.

[0111] The semiconductor storage structure finally formed in this embodiment refers to Fig.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.

[0112] 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.

[0113] It can be understood that the data storage unit in the second and third semiconductor storage structure manufacturing methods provided in the embodiments of the present application can also be set up using the second data storage unit and a similar data storage unit structure, and the manufacturing methods of the external shielding structure, the internal shielding structure, etc. in the semiconductor storage structure manufacturing method are the same as the manufacturing methods of the external shielding structure, the internal shielding structure, etc. in the second and third semiconductor storage structure manufacturing methods, and the specific manufacturing methods will not be described in detail.

[0114] In this specification, each embodiment or implementation is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and 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 application. 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.

[0115] 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 it. Although the present application 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 with 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 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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