Interlayer capacitance measurement unit in magnetic tunnel junction fabrication process and design optimization method

Abstract

The application provides an interlayer capacitance measuring unit in a magnetic tunnel junction preparation process and a design optimization method. The interlayer capacitance measuring unit comprises a first metal layer, a second metal layer and an insulating medium between the first metal layer and the second metal layer. The first metal layer and the second metal layer are respectively provided with the same net-shaped capacitance structure at the corresponding positions. The net-shaped capacitance structure is connected with the electrode block of the same metal layer through a lead. The probe is respectively in contact with the electrode blocks of the two layers to measure the interlayer capacitance value of the net-shaped capacitance structure of the first metal layer and the second metal layer according to the design. If the measured interlayer capacitance value is inconsistent with the interlayer design capacitance value, it indicates that the dielectric constant of the insulating medium selected by the design has a deviation. The insulating medium material selected by the design is replaced or the design thickness of the insulating medium is adjusted for optimization compensation, the optimization adjustment of the interlayer capacitance design is realized, and the requirements of the magnetic tunnel junction preparation process and the device performance are met.

Description

Technical Field

[0001] This invention relates to the field of magnetic electronic device design and manufacturing technology in integrated circuits, and particularly to an interlayer capacitance measurement unit and design optimization method in the fabrication process of a magnetic tunnel junction. Background Technology

[0002] As the integration density of integrated circuits increases and feature sizes shrink, when the feature size decreases to 0.18μm, the resistance and capacitance in the interconnect structure increase rapidly along with the reduction in the cross-section and spacing of the metal interconnects. The resulting interconnect delay will exceed the intrinsic delay of the circuit, becoming a major bottleneck restricting the performance of integrated circuits.

[0003] In existing integrated circuits, aluminum or aluminum alloys have traditionally been used in conjunction with silicon dioxide (SiO2) interconnects because SiO2 possesses excellent thermal stability and moisture resistance, making it the primary insulating material between metal interconnects. However, with advancements in integrated circuit technology, high-speed, high-device-density, and low-power chips have become the dominant integrated circuit products. Consequently, the wire density within chips is continuously increasing, while wire width and spacing are decreasing. The parasitic effects of resistance (R) and capacitance (C) in interconnects are becoming increasingly pronounced. Therefore, optimizing inter-layer interconnect design has become an unavoidable challenge in the layout design and testing of integrated MRAM. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an interlayer capacitance measurement unit in the fabrication process of a magnetic tunnel junction, comprising a first metal layer, a second metal layer, and an insulating medium located between the first metal layer and the second metal layer.

[0005] The first metal layer and the second metal layer are respectively provided with the same mesh capacitor structure at corresponding positions; the mesh capacitor structure is connected to the electrode block of the same metal layer through leads.

[0006] Optionally, the mesh capacitor structure includes multiple capacitor blocks arranged in a square matrix at intervals, and each capacitor block is connected to its adjacent capacitor block.

[0007] Optionally, the capacitor electrode is square and has a size range of 1μm-20μm.

[0008] Optionally, the first metal layer and the second metal layer are parallel to each other.

[0009] Optionally, the spacing between the capacitor electrodes is 1μm-90μm, and the connection between adjacent capacitor electrodes uses interconnecting lines with a size range of 1μm-10μm.

[0010] Optionally, the probe contacts the electrode blocks of the first metal layer and the second metal layer respectively to measure the interlayer capacitance value of the mesh capacitor structure of the first and second metal layers according to the design. If the measured interlayer capacitance value does not match the interlayer design capacitance value, it indicates that there is a deviation in the dielectric constant of the insulating medium selected in the design. The design can be optimized and compensated by changing the insulating medium selected in the design or adjusting the design thickness of the insulating medium, so as to meet the requirements of the magnetic tunnel junction fabrication process and device performance.

[0011] Optionally, if optimization compensation is achieved by changing the insulation medium selected in the design, the dielectric constant is calculated using the following formula to select the insulation medium for the design:

[0012]

[0013] In the above formula, ε represents the dielectric constant of the insulating medium; C 设 The value represents the interlayer design capacitance, which is the capacitance value that meets the requirements of the process and device performance; k represents the electrostatic constant; d represents the design thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

[0014] Optionally, the interlayer capacitance value is measured using the capacitance mode of a digital multimeter.

[0015] The present invention also provides a method for measuring the dielectric constant of the interlayer insulating medium in the magnetic tunnel junction fabrication process, wherein the interlayer capacitance value is obtained by measuring the interlayer capacitance using the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process described in claim 1.

[0016] The dielectric constant of the interlayer insulation medium is then calculated using the following formula:

[0017]

[0018] In the above formula, ε represents the dielectric constant of the insulating medium; C 测 denoted by , k represents the measured interlayer capacitance value; d represents the electrostatic constant; d represents the designed thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

[0019] This invention also provides a method for optimizing the interlayer capacitance design in the fabrication process of a magnetic tunnel junction. The interlayer capacitance value is obtained by measuring the interlayer capacitance using the interlayer capacitance measurement unit in the above-mentioned magnetic tunnel junction fabrication process. If the measured interlayer capacitance value does not match the designed interlayer capacitance value, it indicates that there is a deviation in the dielectric constant of the selected insulating medium. The optimization and compensation can be performed by changing the selected insulating medium or adjusting the design thickness of the insulating medium, thereby meeting the requirements of the magnetic tunnel junction fabrication process and device performance.

[0020] Optionally, if optimization compensation is achieved by changing the insulation medium selected in the design, the dielectric constant is calculated using the following formula to select the insulation medium for the design:

[0021]

[0022] In the above formula, ε represents the dielectric constant of the insulating medium; C 设 The value represents the interlayer design capacitance, which is the capacitance value that meets the requirements of the process and device performance; k represents the electrostatic constant; d represents the design thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

[0023] The present invention discloses an interlayer capacitance measurement unit and its design optimization method in the magnetic tunnel junction fabrication process. The interlayer capacitance measurement unit includes an insulating medium between and between a first metal layer and a second metal layer. Identical mesh capacitor structures are respectively disposed at corresponding positions in the first and second metal layers. The mesh capacitor structures are connected to electrode blocks of the same metal layer via leads. By contacting the electrode blocks of the first and second metal layers with probes, the interlayer capacitance values ​​of the two metal layers can be measured. The k-value of a material used as an insulating medium is called its dielectric constant. A low-k dielectric is required between the metal surface and the main metal system to facilitate signal conduction. The capacitance measurement unit designed in this invention obtains capacitance values ​​through this test unit, which can serve as a reliable method for evaluating interlayer dielectrics. If the measured capacitance value is too large, i.e., the k-value is large, it indicates that the material cannot serve as a good interlayer insulating medium; conversely, it can be considered if the k-value is low. Of course, in terms of performance requirements, in addition to having the lowest possible dielectric constant, other performance characteristics must also be considered, such as a high breakdown electric field and low leakage current. According to the interlayer capacitance measurement unit of the present invention, a low dielectric material that meets the performance requirements can be selected through a simple capacitance test, or the dielectric thickness can be increased or decreased based on the determined dielectric material to meet the requirements.

[0024] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0026] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0027] Figure 1This is a three-dimensional schematic diagram showing the layered disassembly of an interlayer capacitance measurement unit in a magnetic tunnel junction fabrication process according to an embodiment of the present invention.

[0028] Figure 2 This is a schematic elevation view of an embodiment of the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process of the present invention;

[0029] Figure 3 This is a planar schematic diagram of an embodiment of the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process of the present invention;

[0030] Figure 4 This is a schematic planar diagram of the mesh capacitor structure in an embodiment of the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process of the present invention.

[0031] In the figure: 1-first metal layer, 2-second metal layer, 3-insulating medium, 4-mesh capacitor structure, 5-lead, 6-electrode block, 7-capacitor electrode block, 8-interconnection line. Detailed Implementation

[0032] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0033] like Figure 1-4 As shown, an embodiment of the present invention provides an interlayer capacitance measurement unit in the fabrication process of a magnetic tunnel junction, comprising a first metal layer 1, a second metal layer 2, and an insulating dielectric 3 located between the first metal layer 1 and the second metal layer 2;

[0034] The first metal layer 1 and the second metal layer 2 are respectively provided with the same mesh capacitor structure 4 at corresponding positions; the mesh capacitor structure 4 is connected to the electrode block 6 of the same metal layer through the lead wire 5.

[0035] The working principle and beneficial effects of the above technical solution are as follows: The interlayer capacitance measurement unit of this solution includes an insulating medium between the first metal layer and the second metal layer and between the two. The first metal layer and the second metal layer are respectively provided with the same mesh capacitor structure at corresponding positions. The mesh capacitor structure is connected to the electrode block of the same metal layer through leads. By contacting the electrode blocks of the first metal layer and the second metal layer with probes, the interlayer capacitance value of the two metal layers can be measured.

[0036] In one embodiment, such as Figure 1 , 3 As shown in Figure 4, the mesh capacitor structure 4 includes a plurality of capacitor blocks 7 arranged in a square matrix at intervals, and each capacitor block 7 is connected to its adjacent capacitor block.

[0037] The working principle and beneficial effects of the above technical solution are as follows: The mesh capacitor structure in this solution includes multiple capacitor blocks, which are arranged in a square matrix shape with intervals. Adjacent capacitor blocks are connected to each other, that is, each capacitor block is connected to other capacitor blocks in front, behind, left, and right, forming an overall mesh capacitor structure. During measurement, the interlayer capacitance values ​​of the relative double-layer mesh capacitor structure can be measured, avoiding the measurement difficulty and insufficient accuracy caused by the small interlayer capacitance values ​​measured one by one, and also reducing the workload of measuring the overall interlayer capacitance value. The capacitor blocks are single-pole modules, that is, capacitor anode plates or cathode plates. The capacitor blocks of the same metal layer have the same polarity, and the capacitor blocks of different metal layers have different polarities.

[0038] In one embodiment, such as Figure 1 and 4 As shown, the first metal layer 1 and the second metal layer 2 are parallel to each other; the capacitor electrode 7 is square and has a size range of 1μm-20μm, for example, an 8μm*4μm size can be used; the spacing between the capacitor electrodes 7 is 1μm-90μm, for example, a spacing of 2μm can be selected; the connection between adjacent capacitor electrodes 7 adopts an interconnect line 8 with a size range of 1μm-10μm, for example, an interconnect line with a width of 2μm and a length of 2μm can be selected.

[0039] The working principle and beneficial effects of the above technical solution are as follows: This solution makes the first metal layer and the second metal layer parallel to each other, so that the thickness of the insulating medium between the metal layers is uniform, avoiding the adverse effect of thickness difference on the capacitance value; the capacitor electrode is set as square, with a size of 8μm*4μm, which is convenient for arranging in a square matrix; the spacing between the capacitor electrodes is equal, and adjacent capacitor electrodes are connected by interconnecting lines with a width of 2μm and a length of 2μm to form a planar mesh structure, which ensures the consistency and stability of the connection, and also improves the compactness and aesthetics of the structure.

[0040] In one embodiment, the probe contacts the electrode blocks of the first metal layer and the second metal layer respectively to measure the interlayer capacitance value of the mesh capacitor structure of the first and second metal layers according to the design. The interlayer capacitance value can be measured using the capacitance mode (CAP mode) of a digital multimeter. If the measured interlayer capacitance value does not match the designed interlayer capacitance value, it indicates that there is a deviation in the dielectric constant of the insulating medium selected in the design. The optimization and compensation can be carried out by changing the selected insulating medium or adjusting the design thickness of the insulating medium, so as to meet the requirements of the magnetic tunnel junction fabrication process and device performance.

[0041] The working principle and beneficial effects of the above technical solution are as follows: This solution uses the aforementioned interlayer capacitance measurement unit to measure the interlayer capacitance value of the two metal layers by contacting the electrode blocks of the first and second metal layers with a probe. The k-value of a material used as an insulating medium is called its dielectric constant. A low-k dielectric is needed between the metal surface and the main metal system to facilitate signal conduction. The capacitance measurement unit designed in this invention obtains the capacitance value through this test unit, which can serve as a reliable method for evaluating interlayer dielectrics. If the measured capacitance value is too large, i.e., the k-value is large, it indicates that the material cannot serve as a good interlayer insulating medium; conversely, it can be considered. Of course, in terms of performance requirements, in addition to having the lowest possible dielectric constant, other performance characteristics must also be considered, such as a high breakdown electric field and low leakage current. According to the interlayer capacitance measurement unit of this invention, a low-k dielectric material that meets performance requirements can be selected through a simple capacitance test, or the dielectric thickness can be increased or decreased based on the determined dielectric material to meet the requirements.

[0042] In one embodiment, if optimization compensation is achieved by changing the insulation medium selected in the design, the dielectric constant is calculated using the following formula to select the insulation medium for the design:

[0043]

[0044] In the above formula, ε represents the dielectric constant of the insulating medium; C 设 The value represents the interlayer design capacitance, which is the capacitance value that meets the requirements of the process and device performance; k represents the electrostatic constant; d represents the design thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

[0045] The working principle and beneficial effects of the above technical solution are as follows: This solution is designed for the situation of optimizing compensation by replacing the insulation medium selected in the design. The dielectric constant of the required insulation medium can be calculated according to the interlayer design capacitance value using the above formula. Thus, the dielectric constant can guide the design and selection of insulation medium, preventing the blindness of insulation medium design and selection, improving design efficiency, and ensuring design effect.

[0046] In one embodiment, the present invention also provides a method for measuring the dielectric constant of the interlayer insulating medium in the magnetic tunnel junction fabrication process, wherein the interlayer capacitance value is obtained by measuring the interlayer capacitance using the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process described above.

[0047] The dielectric constant of the interlayer insulation medium is then calculated using the following formula:

[0048]

[0049] In the above formula, ε represents the dielectric constant of the insulating medium; C 测denoted by , k represents the measured interlayer capacitance value; d represents the electrostatic constant; d represents the designed thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

[0050] The working principle and beneficial effects of the above technical solution are as follows: This solution uses the aforementioned interlayer capacitance measurement unit. By contacting the electrode blocks of the first and second metal layers with a probe, the interlayer capacitance value of the two metal layers can be measured. Then, based on the interlayer capacitance value, the dielectric constant of the interlayer insulating medium can be calculated using the above formula. The k-value of a material used as an insulating medium is called the dielectric constant. The barrier between the metal surface and the main metal system requires a low-k dielectric to facilitate signal conduction. The capacitance measurement unit designed in this invention obtains the capacitance value through this test unit, which can serve as a reliable method for evaluating interlayer dielectrics. If the measured capacitance value is too large, i.e., the k-value is large, it indicates that the material cannot be used as a good interlayer insulating medium; otherwise, it can be considered. Of course, in terms of performance requirements, in addition to the dielectric constant being as low as possible, other performance characteristics must also be considered, such as high breakdown electric field and low leakage current. According to the interlayer capacitance measurement unit of this invention, a low-dielectric material that meets performance requirements can be selected through a simple capacitance test.

[0051] In one embodiment, the present invention also provides a method for optimizing the interlayer capacitance design in the fabrication process of a magnetic tunnel junction. The interlayer capacitance value is obtained by measuring the interlayer capacitance using the interlayer capacitance measurement unit in the above-mentioned magnetic tunnel junction fabrication process. If the measured interlayer capacitance value does not match the interlayer designed capacitance value, it indicates that there is a deviation in the dielectric constant of the insulating medium selected in the design. The optimization and compensation are performed by changing the selected insulating medium or adjusting the design thickness of the insulating medium, thereby meeting the requirements of the magnetic tunnel junction fabrication process and device performance.

[0052] The working principle and beneficial effects of the above technical solution are as follows: This solution uses the aforementioned interlayer capacitance measurement unit. By contacting the electrode blocks of the first and second metal layers with a probe, the interlayer capacitance value of the two metal layers can be measured. The measured interlayer capacitance value is compared with the designed interlayer capacitance value. If the two do not match, it indicates that there is a deviation in the dielectric constant of the selected insulating medium. Optimization and compensation are needed by replacing the selected insulating medium or adjusting the design thickness of the insulating medium, thereby meeting the requirements of the magnetic tunnel junction fabrication process and device performance. The k-value of a material used as an insulating medium is called its dielectric constant. The barrier between the metal surface and the main metal system requires a low-k dielectric to facilitate signal conduction. The capacitance measurement unit designed in this invention obtains the capacitance value through this test unit, which can serve as a reliable method for evaluating the interlayer dielectric. If the measured capacitance value is too large, i.e., the k-value is large, it indicates that the material cannot be used as a good interlayer insulating medium; conversely, it can be considered. Of course, in terms of performance requirements, in addition to having the dielectric constant as low as possible, other performance characteristics must also be considered, such as high breakdown electric field and low leakage current. According to the interlayer capacitance measurement unit of the present invention, a low dielectric material that meets the performance requirements can be selected through a simple capacitance test, or the dielectric thickness can be increased or decreased based on the determined dielectric material to meet the requirements.

[0053] In one embodiment, if the interlayer capacitance design optimization method uses the replacement of the selected insulating medium for optimization compensation, the dielectric constant is calculated using the following formula to select the selected insulating medium:

[0054]

[0055] In the above formula, ε represents the dielectric constant of the insulating medium; C 设 The value represents the interlayer design capacitance, which is the capacitance value that meets the requirements of the process and device performance; k represents the electrostatic constant; d represents the design thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

[0056] The working principle and beneficial effects of the above technical solution are as follows: This solution is designed for the situation of optimizing compensation by replacing the insulation medium selected in the design. The dielectric constant of the required insulation medium can be calculated according to the interlayer design capacitance value using the above formula. Thus, the dielectric constant can guide the design and selection of insulation medium, preventing the blindness of insulation medium design and selection, improving design efficiency, and ensuring design effect.

[0057] Taking a certain magnetic tunnel junction fabrication process as an example, the design employs two metal layers, which are designed to be parallel to each other and separated by an insulating dielectric. Each metal layer has a corresponding number and size of identical mesh capacitor structures. The mesh capacitor structure comprises 70 capacitor electrodes arranged in a 7*10 array, with each individual electrode measuring 8μm*4μm. Each electrode is connected to its adjacent electrodes in the same layer via interconnecting lines 2μm wide and 2μm long, forming the mesh structure. For each layer's mesh capacitor structure, leads connect the single capacitor closest to the electrode in the same layer to a corresponding 100*100μm electrode in the metal layer. The capacitance of the two metal layers can be measured by using a digital multimeter in capacitance mode. Two probes are used to contact the electrode blocks of the two metal layers respectively. The interlayer capacitance value of the two metal layers can be measured. Combined with the known area s, dielectric thickness d, and electrostatic constant k, the dielectric constant ε of the insulating medium can be obtained. If the interlayer design capacitance value is used for calculation, the dielectric constant of the insulating medium required for the design can be obtained, which can be used to select a low dielectric constant material that meets the performance requirements.

[0058] Furthermore, the calculated low dielectric constant can be used for process control in the production of insulating media, such as the known silicon-carbon-oxygen-fluorine (S... i COF (CoF) thin films are high-performance low-dielectric-constant materials. By controlling the film composition and process conditions during production, the dielectric constant can be maintained at around 2.5. According to the interlayer capacitance measurement unit of this invention, simple capacitance tests can be performed on insulating dielectric materials produced by different processes to select the insulating dielectric material that meets the performance requirements. The production control of the insulating dielectric material can then be performed using the same process as the previous production of the selected insulating dielectric material. Of course, in addition to the performance of the insulating dielectric, the preparation of the interlayer insulating dielectric material must also meet the requirements of integrated circuit industrial production to be compatible with modern integrated circuit processes.

[0059] Assume S i When the COF thickness is 5μm, the measured interlayer capacitance is 10C. However, a certain magnetic tunnel junction requires a capacitance of 5C. Without changing the insulating dielectric material, the simplest solution is to increase the COF thickness to 10μm. In other words, given a specific material, the performance requirements of the magnetic tunnel junction can be met by increasing or decreasing the dielectric thickness.

[0060] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An interlayer capacitance measurement unit in a magnetic tunnel junction fabrication process, characterized in that, It includes a first metal layer, a second metal layer, and an insulating medium located between the first metal layer and the second metal layer; The first metal layer and the second metal layer are respectively provided with the same mesh capacitor structure at corresponding positions; the mesh capacitor structure is connected to the electrode block of the same metal layer through leads; The mesh capacitor structure includes multiple capacitor blocks arranged in a square matrix at intervals, and each capacitor block is connected to its adjacent capacitor block. The capacitor electrode is square and its size ranges from 1μm to 20μm; The spacing between the capacitor electrodes is 1μm-90μm, and the connection between adjacent capacitor electrodes uses interconnecting lines with a size range of 1μm-10μm.

2. The interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process according to claim 1, characterized in that, The probe contacts the electrode blocks of the first metal layer and the second metal layer respectively, and measures the interlayer capacitance value of the mesh capacitor structure of the first and second metal layers according to the design. If the measured interlayer capacitance value does not match the interlayer design capacitance value, it indicates that there is a deviation in the dielectric constant of the insulating medium selected in the design. The optimization and compensation can be carried out by changing the insulating medium selected in the design or adjusting the design thickness of the insulating medium, so as to meet the requirements of the magnetic tunnel junction fabrication process and device performance.

3. The interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process according to claim 2, characterized in that, If the design is optimized by changing the insulation medium used, the dielectric constant is calculated using the following formula to select the insulation medium for the design: In the above formula, ε represents the dielectric constant of the insulating medium; C 设 The value represents the interlayer design capacitance, which is the capacitance value that meets the requirements of the process and device performance; k represents the electrostatic constant; d represents the design thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

4. The interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process according to claim 2, characterized in that, The interlayer capacitance value was measured using a digital multimeter in capacitance mode.

5. A method for measuring the dielectric constant of the interlayer insulating medium in the fabrication process of a magnetic tunnel junction, characterized in that, The interlayer capacitance value is obtained by measuring the interlayer capacitance using the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process described in claim 1. The dielectric constant of the interlayer insulation medium is then calculated using the following formula: In the above formula, ε represents the dielectric constant of the insulating medium; C 测 denoted by , k represents the measured interlayer capacitance value; d represents the electrostatic constant; d represents the designed thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

6. A method for optimizing interlayer capacitance design in the fabrication process of a magnetic tunnel junction, characterized in that, The interlayer capacitance value is obtained by measuring the interlayer capacitance using the interlayer capacitance measurement unit in the magnetic tunnel junction fabrication process described in claim 1. If the measured interlayer capacitance value does not match the interlayer design capacitance value, it indicates that there is a deviation in the dielectric constant of the selected insulating medium. The design is optimized and compensated by replacing the selected insulating medium or adjusting the design thickness of the insulating medium, thereby meeting the requirements of the magnetic tunnel junction fabrication process and device performance.

7. The method for optimizing interlayer capacitance design in the magnetic tunnel junction fabrication process according to claim 6, characterized in that, If the design is optimized by changing the insulation medium used, the dielectric constant is calculated using the following formula to select the insulation medium for the design: In the above formula, ε represents the dielectric constant of the insulating medium; C 设 The value represents the interlayer design capacitance, which is the capacitance value that meets the requirements of the process and device performance; k represents the electrostatic constant; d represents the design thickness of the insulating medium between the first and second metal layers; and S represents the facing area of ​​the capacitor electrodes in the mesh capacitor structure.

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