Magnetic memory cell and array

Abstract

The invention provides a magnetic memory cell and array, and relates to the technical field of semiconductors, the magnetic memory cell at least comprises a spin orbit moment layer and a magnetic tunnel junction arranged above the spin orbit moment layer; a first write-in voltage is applied to a write-in path between the top end of a magnetic tunnel junction and at least one end of a spin-orbit moment layer, and meanwhile, the magnetic tunnel junction is short-circuited and the corresponding end of the spin-orbit moment layer is open-circuited, so that the resistance state of the magnetic storage unit is in an open-circuit state; and comparing the simultaneously read detection signal of the magnetic storage unit with a reference signal arranged outside the magnetic storage unit to obtain the data state stored by the magnetic storage unit. According to the SOT-MRAM-based magnetic storage unit, OTP or FTP data reading and writing are realized, and meanwhile, the size of an OTP unit or an FTP unit is reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a magnetic storage unit and array. Background Art

[0002] At present, with the continuous development of magnetoresistive random access memory, magnetic random access memory (MRAM) technology has undergone three generations of changes. Among them, the third-generation magnetic memory, spin-orbit torque magnetic random access memory (SOT-MRAM), usually includes a spin-orbit moment layer and a magnetic tunnel junction (MTJ) set on the spin-orbit moment layer. As a new type of non-volatile memory, SOT-MRAM is compatible with process technology below 22nm and is expected to replace traditional memories such as flash memory. However, how to achieve data storage security is a problem that needs to be solved urgently.

[0003] In memory chips, one-time programmable (OTP) memory devices are usually used to store key data in a fixed manner, such as encryption keys, firmware signatures, serial numbers, addresses, etc. Or one-time programmable memory devices are used to store data that is updated multiple times, such as upgradeable firmware, data log records, etc.

[0004] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art: the fuse in the traditional one-time programmable memory device is made of a metal filament, and data is written by applying a large current at both ends of the metal filament to cause it to fuse, which not only leads to a larger area of ​​the programmable memory device, but also a larger power consumption. If a metal fuse solution is used as an OTP unit in SOT-MRAM, the size of the SOT-MRAM will increase. Therefore, how to realize OTP or finite time programmable (FTP) data reading and writing based on the magnetic storage unit of SOT-MRAM, while reducing the size of the OTP unit or FTP unit, has become a problem that needs to be solved urgently. Summary of the invention

[0005] The present application provides a magnetic storage unit and an array, so as to realize OTP or FTP data reading and writing based on the magnetic storage unit of SOT-MRAM, while reducing the size of the OTP unit or the FTP unit.

[0006] In a first aspect, the present application provides a magnetic storage unit, the magnetic storage unit comprising at least a spin-orbit moment layer and a magnetic tunnel junction disposed above the spin-orbit moment layer;

[0007] Wherein, by applying a first write voltage to a write path between the top of the magnetic tunnel junction and at least one end of the spin-orbit moment layer, the magnetic tunnel junction is short-circuited and the corresponding end of the spin-orbit moment layer is disconnected, so that the resistance state of the magnetic storage unit is in an open state;

[0008] By comparing the detection signal of the magnetic storage cell read at the same time with a reference signal set outside the magnetic storage cell, the data state stored in the magnetic storage cell is obtained.

[0009] In the case of adopting the above technical solution, the present application uses the spin-orbit moment layer and the magnetic tunnel junction arranged above the spin-orbit moment layer to form a magnetic storage unit, based on the application of a first write voltage, the spin-orbit moment layer is disconnected and the magnetic tunnel junction is short-circuited at the same time, so that the magnetic storage unit is in an open state and the resistance state is irreversible, so as to realize a one-time irreversible programming operation to store data; and, the data state stored in the magnetic storage unit is obtained through the detection signal of the magnetic storage unit and the external reference signal to realize data reading. In this way, the magnetic storage unit based on SOT-MRAM is used as an OTP unit to realize OTP data reading and writing. Since the spin-orbit moment layer and the magnetic tunnel junction have a nanoscale structure, the structure of the OTP unit of the present application has a smaller area and lower power consumption than the storage device using a metal fuse, so the present application can improve the integration density of the storage chip and reduce the power consumption of the OTP storage. In addition, since the reference signal is set outside the magnetic storage unit, the flexibility of the reference unit position setting can be improved, thereby improving the scalability of the storage chip.

[0010] In a second aspect, the present application provides a magnetic storage unit, the magnetic storage unit comprising at least a spin-orbit moment layer and a magnetic tunnel junction disposed above the spin-orbit moment layer;

[0011] The first data writing is realized by applying a second writing voltage to the writing path between the top of the magnetic tunnel junction and at least one end of the spin-orbit moment layer to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state;

[0012] By applying a third write voltage to the write path, the corresponding end of the spin-orbit moment layer is disconnected, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to realize a second data write;

[0013] Acquiring the data state stored in the storage unit by comparing the detection signal of the magnetic storage unit read at the same time with a reference signal set outside the storage unit;

[0014] The second write voltage is lower than the third write voltage.

[0015] In the case of adopting the above technical solution, the present application uses the spin-orbit moment layer and the magnetic tunnel junction arranged above the spin-orbit moment layer to form a magnetic storage unit, based on the first application of the second write voltage to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state and the resistance state is irreversible, so as to achieve the first irreversible data writing, if there is a need for re-programming such as changing the storage key, the spin-orbit moment layer can be disconnected based on the second application of the third write voltage, so that the magnetic storage unit is in a disconnected state and the resistance state is irreversible, so as to achieve the second irreversible data writing, therefore, the magnetic storage unit can achieve a limited number of irreversible programmable operations to store data. In this way, the magnetic storage unit based on SOT-MRAM realizes data reading and writing for two programming as an FTP unit. In addition, since the spin-orbit moment layer and the magnetic tunnel junction have a nanoscale structure, the structure of the FTP unit of the present application has a smaller area and lower power consumption than the storage device using a metal fuse, so the present application can improve the integration density of the storage chip and reduce the power consumption of the FTP storage. Moreover, the same magnetic storage unit has the ability to irreversibly program and write data a limited number of times, so the present application can further improve the integration density of the storage chip. In addition, since the reference signal is set outside the magnetic storage unit, the flexibility of the reference unit position setting can be improved, thereby improving the scalability of the storage chip.

[0016] In a third aspect, the present application further provides a magnetic storage array, comprising at least: magnetic storage units as described in the first aspect and / or the second aspect and at least one reference unit arranged in an array;

[0017] The detection signal of the magnetic storage unit and the reference signal of the reference unit are read simultaneously, and the two are compared to read the data state stored in the magnetic storage unit.

[0018] In the case of adopting the above technical solution, the present application uses a magnetic storage unit based on the existing SOT-MRAM array process as an OTP unit to realize OTP data reading and writing, or uses a magnetic storage unit based on the existing SOT-MRAM array process as an FTP unit to read and write FTP data. Since the spin-orbit moment layer and the magnetic tunnel junction have a nanoscale structure, the structure of the OTP unit of the present application has a smaller area and lower power consumption than the storage device using a metal fuse, so the present application can improve the integration density of the storage chip and reduce the power consumption of the OTP storage. Since the reference unit that provides the reference signal is arranged outside the magnetic storage unit, the flexibility of the reference unit position setting can be improved, and the scalability of the storage chip is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0020] Figure 1 A memory state diagram of a SOT-MTJ provided in an embodiment of the present application Figure 1 ; Figure 2 A memory state diagram of a SOT-MTJ provided in an embodiment of the present application Figure 2 ; Figure 3 A storage state diagram of a magnetic storage unit provided in an embodiment of the present application Figure 1 ; Figure 4 A storage state diagram of a magnetic storage unit provided in an embodiment of the present application Figure 2 ; Figure 5 A storage state diagram of a magnetic storage unit provided in an embodiment of the present application Figure 3 ; Figure 6 A schematic diagram of a storage state of a magnetic storage unit with a resistance state selection module provided in an embodiment of the present application Figure 1 ; Figure 7 A schematic diagram of a storage state of a magnetic storage unit with a resistance state selection module provided in an embodiment of the present application Figure 2 ; Figure 8 A schematic diagram of the structure of a magnetic storage unit with a resistance state selection module provided in an embodiment of the present application; Fig. 9 A schematic diagram of a storage state change of a magnetic storage unit provided in an embodiment of the present application Figure 1 ; Fig.10 A schematic diagram of a storage state change of a magnetic storage unit provided in an embodiment of the present application Figure 2 ; Fig.11 A schematic diagram of a storage state change of a magnetic storage unit provided in an embodiment of the present application Figure 3 ; Fig.12 A graph showing experimental data after breakdown of an oxide layer in a magnetic tunnel junction provided in an embodiment of the present application; Fig.13 A graph showing experimental data after a spin-orbit moment layer is fused, provided in an embodiment of the present application; Fig.14 A schematic diagram of a storage state change of a magnetic storage unit with a resistance state selection module provided in an embodiment of the present application Figure 1 ; Fig.15 A schematic diagram of a storage state change of a magnetic storage unit with a resistance state selection module provided in an embodiment of the present application Figure 2 ; Fig.16 A schematic diagram of storage state changes of a magnetic storage unit having a short-circuit state control module and an open-circuit state control module provided in an embodiment of the present application; Fig.17 A schematic diagram of storage state changes of a magnetic storage unit having a short-circuit state control module and an open-circuit state control module formed by a switch tube provided in an embodiment of the present application; Fig.18 A schematic structural diagram of a magnetic storage unit having a short-circuit state control module and an open-circuit state control module formed by a switch tube provided in an embodiment of the present application; Fig.19 A schematic diagram of the structure of a magnetic storage array provided in an embodiment of the present application; Fig. 20 A schematic diagram of the structure of another magnetic storage array provided in an embodiment of the present application; Fig.21 A schematic diagram of setting a reference current of a reference unit in a magnetic storage array provided in an embodiment of the present application; Fig. 22 A schematic diagram of setting a reference current of a reference unit in another magnetic storage array provided in an embodiment of the present application.

[0021] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0022] Here, exemplary embodiments will be described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which the present application belongs. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. It is understood that the terms "first", "second", etc. used in the present application can be used to describe various information or data in this article, but these elements are not limited by these terms. These terms are only used to distinguish the first information from another information. For example, without departing from the scope of the present application, the first action information can be referred to as the second action information, and similarly, the second action information can be referred to as the first action information. Both the first action information and the second action information are action information, but they are not the same action information.

[0024] First, the terms involved in this application are explained:

[0025] Magnetic Tunnel Junction (MTJ): A nanostructure based on spin electronics, widely used in fields such as magnetic random access memory (MRAM) and sensors. The basic structure of MTJ consists of two ferromagnetic layers and a thin insulating layer sandwiched between them.

[0026] Spin Orbit Torque (SOT): is a technology that uses the spin-orbit coupling effect to manipulate the magnetization direction in magnetic materials.

[0027] The characteristic of One-Time Programmable (OTP) memory is that once programming is completed, the data will be permanently saved and cannot be modified or erased again. OTP memory is a non-volatile memory and is suitable for application scenarios where programs or configurations with fixed data are stored. Since the programming process of OTP is irreversible, it can store critical data (such as encryption keys, firmware signatures, serial numbers, and error correction addresses) in a fixed manner, or store data that is updated multiple times, such as upgradeable firmware, data logging, etc.

[0028] Finite Time Programmable (FTP): It is a limited-time programmable memory. Unlike OTP, FTP allows programming and erasing within a limited number of times. Specifically, the number of programming times of FTP is limited. Once the preset programming limit is reached, the memory cannot be programmed again. FTP is suitable for application scenarios that require limited programming updates, such as certain specific tests or debugging, or scenarios where there is a need for reprogramming, such as changing the storage key again.

[0029] The technical solution provided in this application is applied to a memory chip as a programmable memory unit. It should be understood that, generally, as the first case, the programmable memory unit stores key data in a fixed manner, such as encryption keys, firmware signatures, serial numbers, addresses and other information. As the second case, the programmable memory device unit needs data that is updated multiple times, such as upgradeable firmware, data log records, etc.

[0030] The fuse in the traditional one-time programmable memory device is made of metal filaments, and data is written by applying a large current at both ends of the metal filament to cause it to fuse. This not only leads to a larger area of ​​the programmable memory device, but also a larger power consumption. If the metal fuse solution is used as the OTP unit in SOT-MRAM, the size of the SOT-MRAM will increase. Therefore, how to realize the data reading and writing of OTP or FTP based on the magnetic storage unit of SOT-MRAM, while reducing the size of the OTP unit or FTP unit, has become a problem that needs to be solved urgently.

[0031] Based on this, the present application proposes a programmable magnetic storage unit based on a magnetic tunnel junction and a spin-orbit moment layer, which can improve the integration density of a storage chip.

[0032] Among them, MTJ is the basic magnetic storage unit of magnetic random access memory (MRAM), which is one of the main candidates for a new memory technology based on resistance storage of information. The core structure of MTJ is a multilayer film structure composed of ferromagnetic metal, oxide, and ferromagnetic metal stacked in sequence. The magnetization direction of one ferromagnetic layer is difficult to change, which is called a fixed layer; the magnetization direction of the other ferromagnetic layer can be changed by a magnetic field or current, which is called a free layer. When the magnetization direction of the free layer is parallel (P state) or antiparallel (AP state) to the magnetization direction of the fixed layer, the MTJ is in a low resistance or high resistance state, respectively, and the two resistance states can represent binary data "0" and "1", respectively. The oxide layer uses magnesium oxide (MgO) as the dielectric material, and its thickness is at the nanometer level, which affects the resistance value of the MTJ.

[0033] The SOT-MTJ based on the spin orbit torque (SOT) effect is a three-port device, including a spin orbit torque layer at the bottom and a magnetic tunnel junction film thereon, forming a read channel and a write channel.

[0034] Reference Figure 1 and Figure 2 The SOT-MTJ includes a spin-orbit moment layer 10 and a magnetic tunnel junction 20 disposed above the spin-orbit moment layer. When the magnetization direction of the free layer in the magnetic tunnel junction 20 is parallel to the magnetization direction of the fixed layer, the magnetic tunnel junction 20 is in a low resistance state (e.g. Figure 1); When the magnetization direction of the free layer in the magnetic tunnel junction 20 is antiparallel to the magnetization direction of the fixed layer, it is in a high resistance state (such as Figure 2 ), the two resistance states can represent binary data "0" and "1" respectively.

[0035] The magnetic storage unit provided in the embodiment of the present application is implemented based on a SOT-MTJ device, and utilizes the dielectric breakdown characteristics of the SOT-MTJ device itself to achieve higher storage density and more reliable data writing.

[0036] The structure and principle of the technical solution provided by this application are described in detail below with reference to the accompanying drawings.

[0037] In one embodiment, the present application provides a magnetic storage unit, which at least includes the above-mentioned spin-orbit moment layer and a magnetic tunnel junction arranged above the spin-orbit moment layer.

[0038] Reference Figure 3-Figure 5 When writing data, a first write voltage is applied to the write path between the top of the magnetic tunnel junction and at least one end of the spin-orbit moment layer, and the magnetic tunnel junction is short-circuited and the corresponding end of the spin-orbit moment layer is open-circuited, so that the resistance state of the magnetic storage unit is in an open-circuit state.

[0039] After the magnetic storage unit is in the off-circuit state, the detection signal of the magnetic storage unit and the reference signal set outside the magnetic storage unit can be read simultaneously, and the data state of the magnetic storage unit can be obtained by comparing the two signals.

[0040] It should be understood that since at least one end of the spin-orbit moment layer is open circuited, the structure of the magnetic storage unit itself is changed and the change process is irreversible. Therefore, the storage state of the magnetic storage unit is fixed and will not be changed. Therefore, the magnetic storage unit can be used as a one-time programmable storage unit for storing critical data in a fixed manner, such as encryption keys, firmware signatures, serial numbers, addresses and other information.

[0041] Based on the above description, this embodiment uses a spin-orbit moment layer and a magnetic tunnel junction disposed above the spin-orbit moment layer to form a magnetic storage unit, and uses a magnetic storage unit based on SOT-MRAM as an OTP unit to implement OTP data reading and writing. Since the spin-orbit moment layer and the magnetic tunnel junction have a nanoscale structure, the structure of the OTP unit of this application has a smaller area and lower power consumption than a storage device using a metal fuse, so this application can improve the integration density of the storage chip and reduce the power consumption of the OTP storage. In addition, since the reference unit providing the reference signal is disposed outside the magnetic storage unit, the flexibility of the reference unit position setting can be improved, thereby improving the scalability of the storage chip.

[0042] The following is a description of the principle of the short circuit of the magnetic tunnel junction and the open circuit of the spin-orbit moment layer in the embodiment of the present application:

[0043] The oxide layer in the magnetic tunnel junction has a dielectric breakdown effect. When the voltage at both ends of the write path is large enough, the oxide layer will be permanently broken down to form a short circuit. At this time, the magnetic tunnel junction is equivalent to an antifuse. After the magnetic tunnel junction is short-circuited and broken down, the resistance value will drop significantly and the current will increase significantly. The Joule heat generated will cause the corresponding end of the spin-orbit moment layer to be disconnected. At this time, the spin-orbit moment layer is equivalent to a fuse.

[0044] The corresponding end of the spin-orbit moment layer can be understood as one end or two ends of the spin-orbit moment layer forming a writing path.

[0045] The corresponding relationship between the write path and the corresponding end of the spin-orbit moment layer is explained below with reference to specific examples.

[0046] Reference Figure 3 In one example, a write path is formed between the top of the magnetic tunnel junction 20 and the first end 101 of the spin-orbit moment layer 10, and then a first write voltage is applied to the write path to simultaneously short-circuit the magnetic tunnel junction and open the first end 101 of the spin-orbit moment layer, so that the resistance state of the magnetic storage unit is an open state. At this time, the first end 101 of the spin-orbit moment layer is the corresponding end.

[0047] It should be understood here that, in this example, the first write voltage can be applied to the write path from the top of the magnetic tunnel junction 20, at which time, the first end 101 of the spin-orbit moment layer is grounded or connected to the low voltage end, and the current flows from the top of the magnetic tunnel junction 20 to the first end 101 of the spin-orbit moment layer. The first write voltage can also be applied to the write path from the first end 101 of the spin-orbit moment layer, at which time, the top of the magnetic tunnel junction 20 is grounded or connected to the low voltage end, and the current flows from the first end 101 of the spin-orbit moment layer to the top of the magnetic tunnel junction 20.

[0048] Reference Figure 4 In another example, a write path is formed between the top of the magnetic tunnel junction 20 and the second end 102 of the spin-orbit moment layer 10, and then a first write voltage is applied to the write path to simultaneously short-circuit the magnetic tunnel junction and open the second end 102 of the spin-orbit moment layer, so that the resistance state of the magnetic storage unit is an open state. At this time, the second end 102 of the spin-orbit moment layer is the corresponding end.

[0049] It should be understood here that, in this example, the first write voltage can be applied to the write path from the top of the magnetic tunnel junction 20, at which time, the second end 102 of the spin-orbit moment layer is grounded or connected to the low voltage end, and the current flows from the top of the magnetic tunnel junction 20 to the second end 102 of the spin-orbit moment layer. The first write voltage can also be applied to the write path from the second end 102 of the spin-orbit moment layer, at which time, the top of the magnetic tunnel junction 20 is grounded or connected to the low voltage end, and the current flows from the second end 102 of the spin-orbit moment layer to the top of the magnetic tunnel junction 20.

[0050] Reference Figure 5 In another example, a write path is formed between the top of the magnetic tunnel junction 20 and the first end 101 and the second end 102 of the spin-orbit moment layer 10, and then a first write voltage is applied to the write path to simultaneously short-circuit the magnetic tunnel junction and disconnect the first end 101 and the second end 102 of the spin-orbit moment layer, so that the resistance state of the magnetic storage unit is in an open state. At this time, the first end 101 and the second end 102 of the spin-orbit moment layer are both the corresponding ends mentioned above.

[0051] It should be understood here that, in this example, the first write voltage can be applied to the write path from the top of the magnetic tunnel junction 20, at which time, the first end 101 and the second end 102 of the spin-orbit moment layer are grounded or connected to the low voltage end, and the current flows from the top of the magnetic tunnel junction 20 to the first end 101 and the second end 102 of the spin-orbit moment layer. The first write voltage can also be applied to the write path from the first end 101 and the second end 102 of the spin-orbit moment layer, at which time, the top of the magnetic tunnel junction 20 is grounded or connected to the low voltage end, and the current flows from the first end 101 and the second end 102 of the spin-orbit moment layer to the top of the magnetic tunnel junction 20.

[0052] In this way, the position where the first write voltage is applied can be flexibly set, which is beneficial to simplifying the design of the peripheral circuit structure and can improve the flexibility of programmable operations to improve the scalability of the memory chip.

[0053] In an alternative embodiment, referring to Figure 6 and Figure 7 The magnetic storage unit provided in this embodiment may further include a resistance state selection module 30. The resistance state selection module 30 is electrically connected to the write path.

[0054] By turning on the resistance state selection module 30, a first write voltage can be applied to the write path, and the magnetic tunnel junction is short-circuited and the spin-orbit moment layer is disconnected, so that the magnetic storage unit is in an open state.

[0055] Specifically, in one example, refer to Figure 6, one end of the resistance state selection module 30 can be connected to the write path through the top of the magnetic tunnel junction 20, and the other end of the resistance state selection module 30 is connected to the write voltage end. At this time, the first end 101 of the spin-orbit moment layer is connected to the source line SL, and the source line SL is used to provide a low voltage to the first end 101 of the spin-orbit moment layer. By turning on the resistance state selection module 30, the first write voltage is applied to the write path. It should be understood that the first end 101 of the spin-orbit moment layer can also be directly grounded.

[0056] In another example, referring to Figure 7 , the resistance state selection module 30 can be connected to the write path through the first end 101 of the spin-orbit moment layer, and the other end of the resistance state selection module 30 is connected to the write voltage end. At this time, the top of the magnetic tunnel junction 20 is connected to the source line SL, and the source line SL is used to provide a low voltage to the top of the magnetic tunnel junction 20. By turning on the resistance state selection module 30, the first write voltage is applied to the write path. It should be understood that the top of the magnetic tunnel junction 20 can also be directly grounded.

[0057] The above two examples only show Figure 3 In the case where the resistance state selection module 30 is set in the storage unit in Figure 4 and Figure 5 The magnetic storage unit in the embodiment can be provided with the resistance state selection module 30 in the same manner, which will not be described in detail here.

[0058] Optionally, the resistance state selection module 30 includes but is not limited to a switch tube or multiple switch tubes connected in parallel, the input end of the switch tube is connected to the write voltage end, the output end is connected to the write path, and the control end is connected to the external control signal end. The external control signal end is used to control the conduction of the switch tube.

[0059] Exemplarily, the switch tube includes but is not limited to a bipolar junction transistor (BJT), a metal-oxide-semiconductor field-effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT), or one or more other types of switch tubes, and the embodiments of the present application do not specifically limit this.

[0060] It should be understood that in order to ensure the first write voltage applied to the write path, the magnetic tunnel junction can be short-circuited and the corresponding end of the spin-orbit moment layer can be disconnected at the same time, and the saturation current of the resistance state selection module is greater than or equal to the disconnection current of the spin-orbit moment layer.

[0061] For example, refer to Figure 8When the resistance state selection module includes a switch tube S1, the saturation current of the switch tube S1 should be greater than or equal to the circuit-breaking current of the spin-orbit moment layer, so that the saturation current of the switch tube (that is, the maximum current that can be carried) is greater than or equal to the current that can cause the spin-orbit moment layer to be disconnected.

[0062] Optionally, when the off-circuit current of the spin-orbit moment layer is large, the resistance state selection module includes a plurality of transistors connected in parallel, and the plurality of transistors connected in parallel provide a first write voltage to the write circuit to meet the off-circuit current of the spin-orbit moment layer. The sum of the saturation currents of the plurality of transistors is greater than or equal to the off-circuit current of the spin-orbit moment layer. The number of the plurality of transistors can be set to two or three.

[0063] In an optional embodiment, in order to facilitate reading of the short-circuit state data and the open-circuit state data of the magnetic storage unit, optionally, by applying a first write voltage to the write path between the top of the magnetic tunnel junction and one end of the spin-orbit moment layer, the magnetic tunnel junction is short-circuited and the corresponding end of the spin-orbit moment layer is open-circuited, and the open-circuited end is used as the data reading end and the other end as the data reading and writing end. The detection signal of the magnetic storage unit can be read through the data reading end and the data reading and writing end.

[0064] Then, the detection signal is compared with a reference signal disposed outside the magnetic storage unit to obtain the data state stored in the magnetic storage unit.

[0065] The reference unit may be disposed at any position in the storage chip where the magnetic storage unit is located, and the embodiment of the present application does not impose any special limitation on this.

[0066] In this way, the end of the spin-orbit moment layer where the circuit is broken can only be read but not written, so the broken state data of the magnetic storage unit can be read; while the end of the spin-orbit moment layer where the circuit is not broken can be read and written, so the short-circuit state data of the magnetic storage unit can be read, and the data can be programmed to be written again; the short-circuit state data and the broken state data of the magnetic storage unit can be read, and the data can be programmed to be written again, which is beneficial to improving the data storage density and increasing the number of programmable times.

[0067] In some examples, the comparison between the reference signal and the detection signal can be implemented by a comparator circuit, and the comparison result is used to determine the data state of the magnetic storage unit. For example, if the detection signal matches the reference signal or exceeds a certain threshold, the magnetic storage unit is determined to be in one data state (e.g., "1"). If the detection signal is lower than the reference signal or does not match, the magnetic storage unit is determined to be in another data state (e.g., "0").

[0068] In another embodiment, the present application also provides another magnetic storage unit, referring to Fig. 9 , Fig.10 and Fig.11 , the magnetic storage unit at least includes a spin-orbit moment layer 10 and a magnetic tunnel junction 20 disposed above the spin-orbit moment layer 10;

[0069] When writing data, a second writing voltage is applied to the writing path between at least one end of the spin-track moment layer 10 at the top of the magnetic tunnel junction 20 to short-circuit the magnetic tunnel junction 20, so that the magnetic storage unit is in a short-circuit state to achieve the first data writing.

[0070] Afterwards, a third write voltage may be applied to the write path to disconnect the corresponding end of the spin-track moment layer 10 so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to implement a second data write.

[0071] The detection signal of the magnetic storage unit read at the same time and a reference signal set outside the magnetic storage unit are compared to obtain the data state stored in the magnetic storage unit.

[0072] After the first data writing and the second data writing, the data state stored in the magnetic storage unit can be obtained by comparing the detection signal of the magnetic storage unit read simultaneously with the reference signal set outside the magnetic storage unit.

[0073] The second write voltage is lower than the third write voltage.

[0074] It should be understood that the magnetic storage unit in this embodiment can implement the first irreversible data writing and the second irreversible data writing, so the magnetic storage unit can store data that needs to be updated, such as upgradeable firmware, data log records, etc.

[0075] Based on the above description, this embodiment uses a spin-orbit moment layer and a magnetic tunnel junction disposed above the spin-orbit moment layer to form a magnetic storage unit, and a magnetic storage unit based on the existing SOT-MRAM array process is used as an FTP unit to realize data reading and writing for two programming. On the one hand, since the spin-orbit moment layer and the magnetic tunnel junction have a nanoscale structure, the structure of the FTP unit of the present application has a smaller area and lower power consumption relative to the storage device using a metal fuse, so the present application can improve the integration density of the storage chip and reduce the power consumption of the FTP storage. On the other hand, the same magnetic storage unit in this embodiment has the ability to irreversibly program and write data for a limited number of times, so the integration density of the storage chip can be further improved. In addition, the flexibility of setting the reference unit position can be improved.

[0076] The principle of twice data writing in this embodiment is described below:

[0077] The first data writing: the breakdown of the oxide layer in the magnetic tunnel junction: after the first writing voltage is applied to the writing path, the free electrons in the oxide layer crystals are accelerated in the strong electric field and accumulate a large amount of kinetic energy, which is enough to destroy the molecular structure of the medium. When a chain reaction of collision and ionization occurs, a conductive channel penetrating the oxide layer is generated, causing the oxide layer to lose its insulation properties and form a short circuit, resulting in electrical breakdown. The breakdown effect of the oxide layer measured in the experiment is shown in Figure 2. Fig.12 As shown:

[0078] When the second write voltage applied to the write channel increases from 0V, the oxide layer is broken down at -1.7V, the magnetic tunnel junction is short-circuited, and the resistance is reduced from 20 kiloohms to several hundred ohms.

[0079] Second data writing: After the oxide layer is broken down, the resistance of the magnetic tunnel junction is reduced to the order of hundreds of ohms. At this time, the current generated by the same write voltage will increase to the order of milliamperes. The Joule heat generated causes the atoms in the spin-orbit moment layer, which is only a few tenths of a nanometer thick, to diffuse and form a circuit, and the resistance reaches the order of one billion ohms. The resistance of the spin-orbit moment layer after it is melted is measured in the experiment. Fig.13 shown.

[0080] The corresponding end of the spin-orbit moment layer can be understood as one end or two ends of the spin-orbit moment layer forming a writing path.

[0081] It should be understood that after a short circuit occurs in the magnetic tunnel junction, the resistance of the magnetic tunnel junction itself is reduced to the order of hundreds of ohms, which is a relatively small resistance. At this time, the current generated by the third write voltage that is the same as the second write voltage will increase to the order of milliamperes. The Joule heat generated causes the atoms in the spin-orbit moment layer, which is only a few tenths of a nanometer thick, to diffuse and form a short circuit. Therefore, the second write voltage can be basically the same as the third write voltage in some cases.

[0082] The corresponding relationship between the write path and the corresponding end of the spin-orbit moment layer is explained below with reference to specific examples.

[0083] Reference Fig. 9 In one example, a write path is formed between the top of the magnetic tunnel junction 20 and the first end 101 of the spin-orbit moment layer 10, and then a second write voltage is applied to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to achieve the first data writing. A third write voltage is applied to the write path to open the first end 101 of the spin-orbit moment layer, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to achieve the second data writing. At this time, the first end 101 of the spin-orbit moment layer is the corresponding end mentioned above.

[0084] It should be understood here that, in this example, the second write voltage and the third write voltage can be applied to the write path from the top of the magnetic tunnel junction 20, at which time, the first end 101 of the spin-orbit moment layer is grounded or connected to the low voltage end, and the current flows from the top of the magnetic tunnel junction 20 to the first end 101 of the spin-orbit moment layer. The second write voltage and the third write voltage can also be applied to the write path from the first end 101 of the spin-orbit moment layer, at which time, the top of the magnetic tunnel junction 20 is grounded or connected to the low voltage end, and the current flows from the first end 101 of the spin-orbit moment layer to the magnetic tunnel junction 20.

[0085] Reference Fig.10 In another example, a write path is formed between the top of the magnetic tunnel junction 20 and the second end 102 of the spin-orbit moment layer 10, and then a second write voltage is applied to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to achieve the first data writing. A third write voltage is applied to the write path to open the second end 102 of the spin-orbit moment layer, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to achieve the second data writing. At this time, the second end 102 of the spin-orbit moment layer is the corresponding end mentioned above.

[0086] It should be understood here that, in this example, the second write voltage and the third write voltage can be applied to the write path from the top of the magnetic tunnel junction 20, at which time, the second end 102 of the spin-orbit moment layer is grounded or connected to the low voltage end, and the current flows from the top of the magnetic tunnel junction 20 to the second end 102 of the spin-orbit moment layer. The second write voltage and the third write voltage can also be applied to the write path from the second end 102 of the spin-orbit moment layer, at which time, the top of the magnetic tunnel junction 20 is grounded or connected to the low voltage end, and the current flows from the second end 102 of the spin-orbit moment layer to the magnetic tunnel junction 20.

[0087] Reference Fig.11 In another example, a write path is formed between the top of the magnetic tunnel junction 20 and the first end 101 and the second end 102 of the spin-orbit moment layer 10, and then a second write voltage is applied to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to achieve the first data writing. A third write voltage is applied to the write path to open the first end 101 and the second end 102 of the spin-orbit moment layer, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to achieve the second data writing. At this time, the first end 101 and the second end 102 of the spin-orbit moment layer are both the corresponding ends mentioned above.

[0088] It should be understood here that, in this example, the second write voltage and the third write voltage can be applied to the write path from the top of the magnetic tunnel junction 20, at which time, the first end 101 and the second end 102 of the spin-orbit moment layer are grounded or connected to the low voltage end, and the current flows from the top of the magnetic tunnel junction 20 to the first end 101 and the second end 102 of the spin-orbit moment layer. The second write voltage and the third write voltage can also be applied to the write path from the first end 101 and the second end 102 of the spin-orbit moment layer, at which time, the top of the magnetic tunnel junction 20 is grounded or connected to the low voltage end, and the current flows from the first end 101 and the second end 102 of the spin-orbit moment layer to the top of the magnetic tunnel junction 20.

[0089] In an optional implementation, the magnetic storage unit in this embodiment further includes at least a resistance state selection module 30, and the resistance state selection module 30 is electrically connected to the write path.

[0090] wherein, by turning on the resistance state selection module, a second write voltage is applied to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to implement the first data writing; or,

[0091] By turning on the resistance state selection module, a third write voltage is applied to the write path to disconnect the corresponding end of the spin orbit moment layer, so that the magnetic storage unit is changed from a short circuit state to an open circuit state to realize the second data writing.

[0092] Specifically, in one example, refer to Fig.14 , one end of the resistance state selection module 30 can be connected to the write path through the top of the magnetic tunnel junction 20, and the other end of the resistance state selection module 30 is connected to the write voltage end. At this time, the first end 101 of the spin-orbit moment layer is connected to the source line SL, and the source line SL is used to provide a low voltage to the first end 101 of the spin-orbit moment layer. By turning on the resistance state selection module 30, the second write voltage is applied to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to achieve the first data writing. Or, by turning on the resistance state selection module 30, a third write voltage is applied to the write path to open the first end 101 of the spin-orbit moment layer, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to achieve the second data writing.

[0093] It should be understood that the first end 101 of the spin-track moment layer may also be directly grounded.

[0094] In another example, referring to Fig.15, the resistance state selection module 30 can be connected to the write path through the first end 101 of the spin-orbit moment layer, and the other end of the resistance state selection module 30 is connected to the write voltage end. At this time, the top of the magnetic tunnel junction 20 is connected to the source line SL, and the source line SL is used to provide a low voltage to the top of the magnetic tunnel junction 20. By turning on the resistance state selection module 30, the second write voltage is applied to the write path. The magnetic tunnel junction is short-circuited so that the magnetic storage unit is in a short-circuit state to achieve the first data writing. Or, by turning on the resistance state selection module 30, a third write voltage is applied to the write path to open the first end 101 of the spin-orbit moment layer, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to achieve the second data writing.

[0095] It should be understood that the top of the magnetic tunnel junction 20 may also be directly grounded.

[0096] The above two examples only show Fig. 9 In the case where the resistance state selection module 30 is set in the storage unit in Fig.10 and Fig.11 The storage unit in the embodiment can be provided with the resistance state selection module 30 in the same manner, which will not be described in detail here.

[0097] It should be understood that in this embodiment, when the resistance state selection module is turned on, it can provide the second write voltage or the third write voltage to the write path. When providing the second write voltage, it is necessary to ensure that the second write voltage can short-circuit the magnetic tunnel junction but not open the spin-orbit moment layer. However, when providing the third write voltage, the third write voltage can open the spin-orbit moment layer.

[0098] Based on this, the saturation current of the resistance state selection module needs to be greater than or equal to the short-circuit current of the spin-orbit moment layer. When writing data for the first time, the current output by the resistance state selection module to the write path is greater than or equal to the short-circuit current of the magnetic tunnel junction, and less than the short-circuit current of the spin-orbit moment layer;

[0099] And when writing data for the second time, the current output by the resistance state selection module to the writing path is greater than or equal to the off-circuit current of the spin-orbit moment layer.

[0100] In an alternative embodiment, referring to Fig.16 The resistance state selection module 30 at least includes a short circuit state control module 301 and an open circuit state control module 302 .

[0101] By turning on the short-circuit state control module 301 and turning off the open-circuit state control module 302, a second write voltage can be input into the write path to short-circuit the magnetic tunnel junction 10, so that the magnetic storage unit is in a short-circuit state to implement the first data writing;

[0102] By turning on the disconnection state control module 302, a third write voltage is input to the write path to disconnect the corresponding end of the spin-track moment layer 10, so that the magnetic storage unit is changed from the short-circuit state to the disconnection state to realize the second data writing.

[0103] The saturation current of the short-circuit state control module 301 is greater than or equal to the short-circuit current of the magnetic tunnel junction and less than the open-circuit current of the spin-orbit moment layer, so as to ensure that the magnetic tunnel junction is short-circuited without affecting the spin-orbit moment layer. The saturation current of the open-circuit state control module 302 is greater than or equal to the open-circuit current of the spin-orbit moment layer, so as to ensure that the spin-orbit moment layer can be open-circuited.

[0104] As described above, the short-circuit state and the open-circuit state of the magnetic storage unit are controlled respectively by the short-circuit state control module 301 and the open-circuit state control module 302 to achieve double data writing, thereby improving the reliability of data writing and data storage density of the magnetic storage unit.

[0105] It is worth noting that Fig.16 Only examples are given in Fig. 9 In the case where the short-circuit state control module 301 and the open circuit state control module 302 are set in the storage unit in Fig.10 and Fig.11 The magnetic storage unit in the embodiment can be provided with the resistance state selection module 30 in the same manner, which will not be described in detail here.

[0106] Optional, see Fig.17 In a specific embodiment, the short-circuit state control module may include a first switch tube S1, and the open-circuit state control module may include a first switch tube S1, a second switch tube S2 and a third switch tube S3, and these three switch tubes are arranged in parallel, and the control ends are connected to different control signal lines.

[0107] For example, refer to Fig.17 The control end of the first switch tube S1 is connected to the first control signal line CTL1, the control end of the second switch tube S2 is connected to the second control signal line CTL2, and the control end of the third switch tube S3 is connected to the third control signal line CTL3. The input ends of the first switch tube S1, the second switch tube S2 and the third switch tube S3 are all connected to the bit line BL for receiving the write voltage.

[0108] The first switch tube S1 is used to form a short-circuit state control module 301 , and the second switch tube S2 and the third switch tube S3 are used to form an open-circuit state control module 302 .

[0109] During the first data writing, the first end of the spin-orbit moment layer is connected to the low voltage end through the source line SL, the first control signal in the first control signal line CTL1 controls the first switch tube S1 to be turned on, the second switch tube S2 and the third switch tube S3 to be turned off, and the bit line BL provides a second write voltage to the write path through the first switch tube S1, so that the magnetic tunnel junction is short-circuited, so that the magnetic storage unit is in a short-circuit state.

[0110] During the second data writing, the first end of the spin-orbit moment layer is connected to the low voltage end through the source line SL, the second control signal in the second control signal line CTL2 and the third control signal in the third control signal line CTL3 control the second switch tube S2 and the third switch tube S3 to be turned on, the bit line BL provides the third write voltage to the write path through the second switch tube S2 and the third switch tube S3, and the first end 101 of the spin-orbit moment layer 10 is disconnected, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state.

[0111] For example, refer to Fig.18 The control end of the first switch tube S1 is connected to the read line RWL, and the control ends of the second switch tube S2 and the third switch tube S3 are connected to the limited-time programmable read line FTP-RWL. The first switch tube S1 is used to form a short-circuit state control module 301, and the second switch tube S2 and the third switch tube S3 are used to form an open circuit state control module 302.

[0112] During the first data writing, the read line RWL controls the first switch tube S1 to be turned on, the second switch tube S2 and the third switch tube S3 are turned off, and the bit line BL provides a second write voltage to the write path through the first switch tube S1 to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state.

[0113] During the second data writing, the limited-time programmable read line FTP-RWL controls the second switch tube S2 and the third switch tube S3 to be turned on, and the bit line BL provides the third write voltage to the write path through the second switch tube S2 and the third switch tube S3, and the corresponding end of the spin-orbit moment layer is disconnected, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state.

[0114] In this embodiment, the saturation current of the first switch tube S1 is greater than or equal to the short-circuit current of the magnetic tunnel junction and less than the open-circuit current of the spin-orbit moment layer to ensure that the magnetic tunnel junction is short-circuited without affecting the spin-orbit moment layer.

[0115] The sum of the saturation currents of the second switch tube S2 and the third switch tube S3 is greater than or equal to the disconnection current of the spin-orbit moment layer, so as to ensure that the spin-orbit moment layer can be disconnected.

[0116] In other examples, if the sum of the saturation currents of the second switch tube S2 and the third switch tube S3 is less than the short-circuit current of the spin-orbit moment layer, then when the data is written for the second time, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can be used as short-circuit state control modules to control the first switch tube S1, the second switch tube S2 and the third switch tube S3 to be turned on to ensure that the spin-orbit moment layer can be short-circuited.

[0117] Exemplarily, the first switch tube S1, the second switch tube S2 and the third switch tube S3 can all be bipolar transistors, metal oxide semiconductor field effect transistors and insulated gate bipolar transistors, or other types of switch tubes, and the embodiments of the present application do not specifically limit this.

[0118] It should be understood that the short-circuit state control module in this embodiment can also be provided with a plurality of switch tubes arranged in parallel, and it is only necessary to ensure that the sum of the saturation currents of the plurality of switch tubes is greater than or equal to the short-circuit current of the magnetic tunnel junction and less than the open-circuit current of the spin-orbit moment layer. In this embodiment, the open-circuit state control module can also be provided with a plurality of other numbers of switch tubes, such as 3 or 4, etc., and this embodiment does not make any special limitation on this, and it is only necessary to ensure that the sum of the saturation currents of the plurality of switch tubes is greater than or equal to the open-circuit current of the spin-orbit moment layer.

[0119] In an optional embodiment, in order to facilitate reading the data of the magnetic storage unit in the off-circuit state, optionally, by applying a second write voltage to the write path between the top of the magnetic tunnel junction and one end of the spin-orbit moment layer, the magnetic tunnel junction is short-circuited, and both ends of the spin-orbit moment layer are used as data reading and writing ends; in this way, the short-circuit state data of the magnetic storage unit can be read, and each end of the spin-orbit moment layer can realize programmable writing of data again. Reading the short-circuit state data of the magnetic storage unit and being able to programmably write data again is conducive to improving the storage density of data and increasing the number of programmable times.

[0120] Or, by applying a third write voltage to the write path between the top of the magnetic tunnel junction and one end of the spin-orbit moment layer, the corresponding end of the spin-orbit moment layer is disconnected to serve as the second data reading end, and the other end is used as the fourth data reading and writing end. In this way, the end of the spin-orbit moment layer where the circuit is disconnected can only read but not write, so the disconnected state data of the magnetic storage unit can be read; while the end of the spin-orbit moment layer where the circuit is not disconnected can read and write, so the short-circuit state data of the magnetic storage unit can be read, and data can be reprogrammed and written; the short-circuit state data and disconnected state data of the magnetic storage unit can be read, and data can be reprogrammed and written, which is conducive to improving the data storage density and increasing the number of programmable times.

[0121] The detection signal of the magnetic storage unit can be read through the data read-write end and the data reading end.

[0122] Then, the detection signal is compared with a reference signal disposed outside the magnetic storage unit to obtain the data state stored in the magnetic storage unit.

[0123] The reference unit may be disposed at any position in the memory chip where the memory unit is located, and the embodiment of the present application does not impose any special limitation on this.

[0124] This helps to improve data storage density and increase programmable times.

[0125] Optionally, the first write voltage is equal to the third write voltage.

[0126] In this way, the write voltage for implementing OTP data writing is consistent with the write voltage for implementing the second data writing of FTP, which is beneficial to simplifying the peripheral circuit structure and control logic.

[0127] Optionally, in order to ensure the accuracy of data reading, the magnetic storage unit and the reference unit may share a read line.

[0128] Optionally, the magnetic storage unit and the reference unit may not share a read line, and it is only necessary to read and compare the signals of the two simultaneously.

[0129] In some examples, the comparison between the reference signal and the detection signal can be implemented by a comparator circuit, and the comparison result is used to determine the state of the magnetic storage unit. For example, if the detection signal matches the reference signal or exceeds a certain threshold, the magnetic storage unit is determined to be in one data state (e.g., "1"). If the detection signal is lower than the reference signal or does not match, the magnetic storage unit is determined to be in another data state (e.g., "0").

[0130] Based on the above description, in this embodiment, the magnetic storage unit can adopt the existing SOT-MRAM storage unit design and can be directly arranged in the original MRAM array to reduce the design complexity.

[0131] Reference Fig.19 An embodiment of the present application also provides a magnetic storage array, comprising at least: magnetic storage cells arranged in an array as in the above two embodiments and at least one reference cell; the magnetic storage cells arranged in an array as in the above two embodiments and at least one reference cell can form an OTP / FTP area.

[0132] Specifically, in the magnetic storage unit, the top of the magnetic tunnel junction is electrically connected to the read line RWL, and one end of the spin-orbit moment layer is electrically connected to the source line SL and the read line RWL through the first switch tube S1, so that the top of the magnetic tunnel junction and the corresponding end of the spin-orbit moment layer form a write path; the other end of the spin-orbit moment layer is electrically connected to the bit line BL and the write line WWL through the fourth switch tube S4. The first switch tube S1 serves as a resistance state selection module.

[0133] The detection signal of the magnetic storage unit and the reference signal of the reference unit are read simultaneously, and the two are compared to read the data state stored in the magnetic storage unit.

[0134] The magnetic storage unit and the reference unit may share a read line or may not share a read line, so as to simultaneously read the signals of the two and compare them.

[0135] For example, in order to improve the synchronization and accuracy of data comparison, the magnetic storage unit and the reference unit may be set to share a read line.

[0136] In this way, the magnetic storage unit based on the existing SOT-MRAM array process is used as an OTP unit to realize the data reading and writing of OTP, or the magnetic storage unit based on the existing SOT-MRAM array process is used as an FTP unit to read and write data of FTP. Since the spin-orbit moment layer and the magnetic tunnel junction have a nanoscale structure, the structure of the OTP unit of the present application has a smaller area and lower power consumption than the storage device using a metal fuse, so the present application can improve the integration density of the storage chip and reduce the power consumption of OTP storage. Since the reference unit providing the reference signal is arranged outside the magnetic storage unit, the flexibility of the reference unit position setting can be improved, and the scalability of the storage chip is improved.

[0137] Optional, see Fig. 20 In the magnetic storage unit, the top of the magnetic tunnel junction is electrically connected to the read line RWL, and the first switch tube S1 at one end of the spin-orbit moment layer is electrically connected to the source line SL and the read line RWL respectively, so that the top of the magnetic tunnel junction and the corresponding end of the spin-orbit moment layer form a write path; the other end of the spin-orbit moment layer is suspended and not electrically connected to the bit line BL and the write line WWL. The first switch tube S1 serves as a resistance state selection module.

[0138] In this way, since the magnetic tunnel junction does not need to be flipped from the P state to the AP state in OTP or FTP, no CMOS (Complementary Metal Oxide Semiconductor) is set between one end of the spin-orbit moment layer and the bit line, but it is set in suspension, which is beneficial to further improve the integration density of the magnetic storage array.

[0139] Optional, see Fig.21 When the magnetic tunnel junction is short-circuited but the spin-orbit moment layer is not disconnected, the reference signal provided by the reference unit can be the reference current I Ref , set the magnetic tunnel junction P-state current I p and the magnetic tunnel junction breakdown current I BD Specifically, I Ref Set in the sample of magnetic storage unit Ip The maximum value of I BD between the minimum values ​​of .

[0140] Reference Fig. 22 When the magnetic tunnel junction is short-circuited and the spin-orbit moment layer is disconnected, the reference signal provided by the reference unit can be the reference current I Ref , set the off-circuit current I in the spin-orbit moment layer Open The AP state current I Ap Specifically, I Ref Set in the sample of magnetic storage unit I Open The maximum value of I Ap between the minimum values ​​of .

[0141] In this way, when OTP or FTP realizes data reading, the reference current is set more accurately, which is beneficial to improving the accuracy of OTP or FTP data reading.

[0142] Optionally, the number of reference cells is set to one or more. When the number of reference cells is one, when reading data, the detection signals of multiple magnetic storage cells are compared with the reference signal provided by one reference cell to obtain the data state stored in the magnetic storage cell. When the number of reference cells is multiple and the same as the number of magnetic storage cells, when reading data, the detection signal of each magnetic storage cell is respectively compared with the reference signal provided by the corresponding reference cell to obtain the data state stored in the magnetic storage cell.

[0143] This is helpful to improve the flexibility of reference unit setting and to improve the integration density.

[0144] Optional, see Fig. 20 The reference unit at least includes: a spin-orbit moment layer and a magnetic tunnel junction arranged above the spin-orbit moment layer; the top of the magnetic tunnel junction is electrically connected to the read line RWL, and one end of the spin-orbit moment layer is electrically connected to the source line SL and the read line RWL respectively through the first switch tube S1, so that the top of the magnetic tunnel junction and the corresponding end of the spin-orbit moment layer form a write path; the other end of the spin-orbit moment layer is suspended and is not electrically connected to the bit line BL and the write line WWL.

[0145] In this way, the connection mode between the reference unit and the signal line in the array is consistent with the connection mode between the magnetic storage unit and the signal line in the array, which is conducive to making the reference signal more accurate.

[0146] It should be understood that since the magnetic storage array includes the above-mentioned magnetic storage unit, the magnetic storage array is Figure 3-Figure 18 The beneficial effects of the magnetic storage unit provided in the illustrated embodiment are the same and will not be described in detail here.

[0147] 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 magnetic storage unit, characterized in that: The magnetic storage unit at least includes a spin-orbit moment layer and a magnetic tunnel junction disposed above the spin-orbit moment layer; Wherein, by applying a first write voltage to a write path between the top of the magnetic tunnel junction and at least one end of the spin-orbit moment layer, the magnetic tunnel junction is short-circuited and the corresponding end of the spin-orbit moment layer is disconnected, so that the resistance state of the magnetic storage unit is in an open-circuit state; The detection signal of the magnetic storage unit and a reference signal disposed outside the magnetic storage unit are read simultaneously and compared with each other to obtain the data state stored in the magnetic storage unit.

2. The magnetic storage unit according to claim 1, characterized in that The magnetic storage unit at least further comprises a resistance state selection module, and the resistance state selection module is electrically connected to the write path; Wherein, by turning on the resistance state selection module, a first write voltage is applied to the write path, and at the same time the magnetic tunnel junction is short-circuited and the spin-orbit moment layer is open-circuited, so that the magnetic storage unit is in an open-circuit state.

3. The magnetic storage unit according to claim 2, characterized in that The saturation current of the resistance state selection module is greater than or equal to the off-circuit current of the spin-orbit moment layer.

4. The magnetic storage unit according to claim 1, characterized in that The first write voltage is applied to the write path between the top of the magnetic tunnel junction and one end of the spin-orbit moment layer, and the magnetic tunnel junction is short-circuited and the corresponding end of the spin-orbit moment layer is open-circuited to serve as a data reading end, and the other end is used as a data reading and writing end.

5. A magnetic storage unit, characterized in that: The magnetic storage unit at least includes a spin-orbit moment layer and a magnetic tunnel junction disposed above the spin-orbit moment layer; Wherein, by applying a second write voltage to the write path between the top of the magnetic tunnel junction and at least one end of the spin-orbit moment layer, the magnetic tunnel junction is short-circuited, so that the magnetic storage unit is in a short-circuited state to implement the first data writing; By applying a third write voltage to the write path, the corresponding end of the spin-orbit moment layer is disconnected, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to realize a second data write; By comparing the detection signal of the magnetic storage unit and a reference signal disposed outside the magnetic storage unit, the two are read simultaneously to obtain the data state stored in the magnetic storage unit; The second write voltage is lower than the third write voltage.

6. The magnetic storage unit according to claim 5, characterized in that At least a resistance state selection module is included, and the resistance state selection module is electrically connected to the writing path; wherein, by turning on the resistance state selection module, applying the second write voltage to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to implement the first data writing; or, By turning on the resistance state selection module, the third write voltage is applied to the write path to disconnect the corresponding end of the spin-orbit moment layer, so that the magnetic storage unit is changed from a short-circuit state to an open-circuit state to realize a second data writing.

7. The magnetic storage unit according to claim 6, characterized in that The saturation current of the resistance state selection module is greater than or equal to the off-circuit current of the spin-orbit moment layer; During the first data writing, the current output by the resistance state selection module to the writing path is greater than or equal to the short-circuit current of the magnetic tunnel junction and less than the off-circuit current of the spin-orbit moment layer; During the second data writing, the current output by the resistance state selection module to the writing path is greater than or equal to the off-circuit current of the spin-orbit moment layer.

8. The magnetic storage unit according to claim 6, characterized in that The resistance state selection module at least includes a short circuit state control module and an open circuit state control module; By turning on the short-circuit state control module and turning off the open-circuit state control module, the second write voltage is input to the write path to short-circuit the magnetic tunnel junction, so that the magnetic storage unit is in a short-circuit state to implement the first data writing; By turning on the disconnection state control module, the third write voltage is input to the write path to disconnect the corresponding end of the spin-orbit moment layer, so that the magnetic storage unit is changed from the short-circuit state to the disconnection state to realize the second data writing; Among them, the saturation current of the short-circuit state control module is greater than or equal to the short-circuit current of the magnetic tunnel junction, and less than the open-circuit current of the spin-orbit moment layer; the saturation current of the open-circuit state control module is greater than or equal to the open-circuit current of the spin-orbit moment layer.

9. The magnetic storage unit according to claim 5, characterized in that By applying the second write voltage to the write path between the top of the magnetic tunnel junction and one end of the spin-orbit moment layer, the magnetic tunnel junction is short-circuited, and both ends of the spin-orbit moment layer serve as data reading and writing ends; Alternatively, by applying the third write voltage to the write path between the top of the magnetic tunnel junction and one end of the spin-orbit moment layer, one end of the spin-orbit moment layer is disconnected to serve as a data reading end, and the other end is used as a data reading and writing end.

10. A magnetic storage array, characterized in that: At least comprising: the magnetic storage unit according to any one of claims 1 to 9 and at least one reference unit arranged in an array; The detection signal of the magnetic storage unit and the reference signal of the reference unit are read simultaneously and compared to obtain the data state stored in the storage unit.

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