Complementary resistive switching structure based on hexagonal boron nitride and preparation method therefor

Abstract

A complementary resistive switching structure based on hexagonal boron nitride and a preparation method therefor, which can be applied in the technical field of memristors. The structure (100) comprises: a substrate (110); electrode layers, located above the substrate and comprising a first electrode layer (121), a second electrode layer (122), and a third electrode layer (123), wherein the first electrode layer and the third electrode layer are electrically connected to an external circuit (140), and the potentials of the first electrode layer and the third electrode layer vary in accordance with an input bias voltage signal received from the external circuit; and a resistive switching layer, comprising a first resistive switching layer (131), the first resistive switching layer being located between the first electrode layer and the second electrode layer. The substrate, the electrode layers, and the resistive switching layer at least partially overlap in space. A switching state of the resistive switching layer is switched by adjusting a potential difference between the first electrode layer and the third electrode layer. The material of the resistive switching layer comprises hexagonal boron nitride, and the thickness of the resistive switching layer is 0.5 nm to 10 nm.

Description

Complementary Resistive Switch Structure Based on Hexagonal Boron Nitride and Its Fabrication Method Technical Field

[0001] This disclosure relates to the field of memristor technology, and more specifically, to a complementary resistive switch structure based on hexagonal boron nitride and its fabrication method. Background Technology

[0002] The creeping current problem in cross-memristor arrays limits their size. Therefore, large-scale cross-memristor arrays can be implemented using complementary resistor switches with a high on / off ratio, making them more suitable for applications in in-memory computing, artificial intelligence, and big data processing.

[0003] However, in realizing the concept disclosed herein, the inventors discovered that it is difficult to achieve a small-sized complementary resistor switch with a large switching ratio in the related technology. Summary of the Invention

[0004] In view of this, this disclosure provides a complementary resistive switch structure based on hexagonal boron nitride and its fabrication method.

[0005] One aspect of this disclosure provides a complementary resistive switch structure based on hexagonal boron nitride, comprising:

[0006] A substrate; an electrode layer located above the substrate, comprising a first electrode layer, a second electrode layer, and a third electrode layer, wherein the first electrode layer and the third electrode layer are electrically connected to an external circuit, and the potentials of the first electrode layer and the third electrode layer change with the received bias voltage signal input from the external circuit; a resistor switch layer comprising a first resistor switch layer located between the first electrode layer and the second electrode layer; wherein the substrate, the electrode layer, and the resistor switch layer at least partially overlap in space, and the switching state of the resistor switch layer is switched by adjusting the potential difference between the first electrode layer and the third electrode layer; the material of the resistor switch layer comprises hexagonal boron nitride, and the thickness of the resistor switch layer is 0.5 nm to 10 nm.

[0007] According to embodiments of this disclosure, the first electrode layer and the third electrode layer are located side by side on the same side of the first resistive switch layer.

[0008] According to an embodiment of this disclosure, the resistor switch layer further includes a second resistor switch layer located between the second electrode layer and the third electrode layer.

[0009] According to embodiments of this disclosure, the switching state includes on and off. The switching state of the resistor switch layer is switched by adjusting the potential difference between the first electrode layer and the third electrode layer, including: when the potential of the third electrode layer is higher than the potential of the first electrode layer and the potential difference between the third electrode layer and the first electrode layer is greater than a first threshold, the resistance of the first resistor switch layer decreases until the first resistor switch layer is turned on, and the resistance of the second resistor switch layer increases until the second switch resistor layer is turned off; when the potential of the first electrode layer is higher than the potential of the third electrode layer and the potential difference between the first electrode layer and the third electrode layer is greater than a second threshold, the resistance of the second resistor switch layer decreases until the second resistor switch layer is turned on, and the resistance of the first resistor switch layer increases until the first resistor switch layer is turned off.

[0010] According to an embodiment of this disclosure, the switching state of the first resistor switch layer and the switching state of the second resistor switch layer are obtained by the following steps: performing a voltage scan on the first electrode layer and the third electrode layer according to a predetermined voltage range to obtain current data of the first electrode layer or current data of the third electrode layer; and determining the switching state of the first resistor switch layer and the switching state of the second resistor switch layer based on the current data of the first electrode layer or the current data of the third electrode layer.

[0011] According to embodiments of this disclosure, the switching states of the first and second resistor switching layers are obtained by the following steps: applying a first test bias voltage to the second and third electrode layers to obtain first current data flowing through the second and third electrode layers; applying a second test bias voltage to the second and first electrode layers to obtain second current data flowing through the second and first electrode layers; determining the resistance values ​​of the first and second resistor switching layers based on the first and second current data; and determining the switching states of the first and second resistor switching layers based on the resistance values ​​of the first and second resistor switching layers.

[0012] According to embodiments of this disclosure, the above structure further includes: an isolation layer located between the substrate and each electrode layer adjacent to the substrate, the isolation layer covering the overlapping area of ​​the substrate and each electrode layer adjacent to the substrate, and the material of the isolation layer including one of the following: hafnium dioxide, hexagonal boron nitride, and silicon oxide.

[0013] Another aspect of this disclosure provides a method for fabricating a complementary resistive switch structure based on hexagonal boron nitride, comprising:

[0014] Electron beam lithography and electron beam evaporation techniques are used to form an electrode layer on a substrate;

[0015] A resistive switching layer is formed above the electrode layer;

[0016] The remaining electrode layers are then formed above the resistive switch layer;

[0017] The material of the resistive switch layer includes hexagonal boron nitride.

[0018] According to embodiments of this disclosure, forming a resistive switch layer above an electrode layer includes: generating a resistive switch layer made of hexagonal boron nitride on the electrode layer using chemical vapor deposition or mechanical exfoliation.

[0019] Another aspect of this disclosure provides a memristor array, comprising:

[0020] The above-mentioned complementary resistive switch structure based on hexagonal boron nitride.

[0021] According to embodiments of this disclosure, a bias voltage signal is applied to the first electrode layer and the third electrode layer using an external circuit to adjust the potential of the first electrode layer and the third electrode layer, thereby changing the switching state of the resistive switch layer to achieve non-volatile storage of the resistance value. This disclosure uses hexagonal boron nitride as the material of the resistive switch layer, which improves the switching ratio of the device while reducing the threshold voltage required for switching the switching state of the resistive switch layer. This is beneficial for realizing large-scale cross-memristor arrays. At the same time, it ensures that the thickness of the resistive switch layer is only 0.5nm to 10nm. Therefore, compared with the complementary resistive switches of related technologies, the thickness of the resistive switch layer is reduced, thereby compressing the size of the device. This is beneficial for reducing the chip area of ​​three-dimensional integration of memristor arrays. Moreover, two-dimensional hexagonal boron nitride has a certain degree of ductility and can be applied to flexible application scenarios such as wearable devices. Attached Figure Description

[0022] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0023] Figure 1a schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0024] Figure 1b schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0025] Figure 2 schematically shows a top view of a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0026] Figure 3 schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to yet another embodiment of the present disclosure.

[0027] Figure 4a schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0028] Figure 4b schematically shows a top view of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0029] Figure 5 schematically shows a front view of a hexagonal boron nitride-based complementary resistive switch structure including an isolation layer according to an embodiment of the present disclosure.

[0030] Figure 6 schematically illustrates the voltage-current curves of a complementary resistive switch based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0031] Figure 7 schematically illustrates a comparison of the on / off ratio versus threshold voltage ratio of the complementary resistive switch structure based on hexagonal boron nitride according to embodiments of the present disclosure with complementary resistive switches of other material resistive switch layers.

[0032] Figure 8 schematically illustrates a flowchart of a method for fabricating a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0033] Figure 9 schematically illustrates the fabrication process of a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0034] Figure 10 schematically illustrates the fabrication process of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0035] Figure 11 schematically illustrates a block diagram of a memristor array according to an embodiment of the present disclosure. Detailed Implementation

[0036] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0037] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0038] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0039] When using expressions such as "at least one of A, B, and C", they should generally be interpreted in accordance with the meaning that is commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B, and C, etc.).

[0040] Complementary resistor switches utilize two high-resistance states for data storage, significantly suppressing coding and reading errors caused by creeping paths in memristor crossbar arrays, thereby improving array reliability and size limits. This passive, non-volatile device unit helps reduce system power consumption and holds great potential in fields such as artificial intelligence and big data processing.

[0041] In the process of realizing this disclosure, it was discovered that hexagonal boron nitride has advantages such as high thermal conductivity, high insulation, and ultra-thin thickness. Therefore, embodiments of this disclosure provide a complementary resistive switch structure based on hexagonal boron nitride, comprising:

[0042] The substrate; an electrode layer located above the substrate, comprising a first electrode layer, a second electrode layer, and a third electrode layer, wherein the first electrode layer and the third electrode layer are electrically connected to an external circuit, and the potentials of the first electrode layer and the third electrode layer change with the received bias voltage signal input from the external circuit; a resistor switch layer comprising a first resistor switch layer located between the first electrode layer and the second electrode layer; wherein the substrate, the electrode layer, and the resistor switch layer at least partially overlap in space, and the switching state of the resistor switch layer is switched by adjusting the potential difference between the first electrode layer and the third electrode layer; the material of the resistor switch layer comprises hexagonal boron nitride, and the thickness of the resistor switch layer is 0.5 nm to 10 nm.

[0043] Figure 1a schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0044] As shown in Figure 1a, taking a single-layer resistor switch layer as an example, the structure 100 includes a substrate 110, a first electrode layer 121, a second electrode layer 122 and a third electrode layer 123, a first resistor switch layer 131 and an external circuit 140.

[0045] According to embodiments of this disclosure, the substrate 110 can be made of a flexible substrate, a SiC substrate, a silicon oxide wafer, or a diamond substrate, but it is necessary to ensure that there is no leakage current between the hexagonal boron nitride-based complementary resistive switch and the substrate.

[0046] According to embodiments of this disclosure, the electrode layer can be made of a conductive material, including one of the following: gold, chromium, titanium, titanium nitride, or graphene.

[0047] According to an embodiment of the present disclosure, the first electrode layer 121 and the third electrode layer 123 are electrically connected to the external circuit 140, and the potentials of the first electrode layer 121 and the third electrode layer 123 change with the bias voltage signal received from the external circuit 140.

[0048] According to embodiments of this disclosure, the substrate, electrode layer, and resistor switch layer have at least partial spatial overlap. To save space, the area of ​​each layer can be minimized while ensuring the overlap, and the layers can be stacked vertically.

[0049] According to embodiments of this disclosure, hexagonal boron nitride (h-BN) is used as the material for the resistive switch layer, and the interaction between the resistive switch layer and the electrode layer determines the characteristics of the volatile and non-volatile switches.

[0050] According to an embodiment of the present disclosure, the first resistive switch layer can be divided into two sub-layers. The first sub-layer is located between the first electrode layer and the second electrode layer and is used to isolate the first electrode layer and the second electrode layer. The second sub-layer is located between the third electrode layer and the second electrode layer and is used to isolate the third electrode layer and the second electrode layer.

[0051] Figure 1b schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0052] As shown in Figure 1b, structure 100 includes substrate 110, first electrode layer 121, second electrode layer 122 and third electrode layer 123, first sublayer 131(1) and second sublayer 131(2).

[0053] To better understand the above structure 110, the following will provide a better explanation of the top view of the above structure 100 using Figure 2.

[0054] Figure 2 schematically shows a top view of a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0055] As shown in Figure 2, the top view of structure 100 shows the overlapping areas of the substrate, electrode layer, and resistor switch layer in space, namely the first overlapping area 210 and the second overlapping area 220. For the first resistor switch layer 131, only the first overlapping area 210 and the second overlapping area 220 can switch between states, while the remaining areas remain insulated. By switching the switching states of the first overlapping area 210 and the second overlapping area 220, opposite switching states, one on and one off, can be formed as the storage state of the complementary resistor switch.

[0056] According to embodiments of this disclosure, a bias voltage signal is applied to the first electrode layer and the third electrode layer using an external circuit to adjust the potential of the first electrode layer and the third electrode layer, thereby changing the switching state of the resistive switch layer to achieve non-volatile storage of the resistance value. In addition, using hexagonal boron nitride as the material of the resistive switch layer makes the threshold voltage required for switching the switching state of the resistive switch layer smaller, while improving the switching ratio of the device, which is beneficial for realizing large-scale cross-memristor arrays. At the same time, it ensures that the thickness of the resistive switch layer is only 0.5nm to 10nm. Therefore, compared with the complementary resistive switches of related technologies, the thickness of the resistive switch layer is reduced, thereby compressing the size of the device, which is beneficial for reducing the chip area of ​​three-dimensional integration of memristor arrays. Moreover, two-dimensional hexagonal boron nitride has a certain degree of ductility and can be applied to flexible application scenarios such as wearables.

[0057] According to embodiments of this disclosure, the first electrode layer and the third electrode layer are located side by side on the same side of the first resistive switch layer.

[0058] Figure 3 schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to yet another embodiment of the present disclosure.

[0059] As shown in Figure 3, the structure 300 includes a substrate 310, a first electrode layer 321, a second electrode layer 322, a third electrode layer 323, and a first resistor switch layer 331.

[0060] According to embodiments of this disclosure, in the case of a single-layer resistor switch layer, it is only necessary to ensure that the two electrode layers receiving the bias voltage signal input from the external circuit are located on the same side of the first resistor switch layer, while the other electrode layer is located on the other side of the first resistor switch layer.

[0061] According to embodiments of this disclosure, by placing the first electrode layer and the third electrode layer on the same side of the first resistive switch layer, the two resistive switch layers in the related art are combined, which helps to simplify the fabrication process, improve device symmetry, and thus improve device performance.

[0062] According to an embodiment of this disclosure, the resistor switch layer further includes a second resistor switch layer located between the second electrode layer and the third electrode layer.

[0063] According to embodiments of this disclosure, the first electrode layer, the second electrode layer, and the third electrode layer can also be isolated sequentially by the first resistor switch layer and the second resistor switch layer.

[0064] Figure 4a schematically shows a front view of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0065] As shown in Figure 4a, the structure 400 includes a substrate 410, a first electrode layer 421, a second electrode layer 422, a third electrode layer 423, a first resistor switch layer 431, and a second resistor switch layer 432.

[0066] According to embodiments of this disclosure, the switching states of the first resistor switch layer 431 and the second resistor switch layer 432 are adjusted by a bias voltage signal from an external circuit, thereby realizing a complementary resistor switch function.

[0067] Figure 4b schematically shows a top view of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0068] As shown in Figure 4b, the top view of structure 400 corresponds to the front view.

[0069] According to embodiments of this disclosure, the above structure further includes: an isolation layer located between the substrate and each electrode layer adjacent to the substrate, the isolation layer covering the overlapping area of ​​the substrate and each electrode layer adjacent to the substrate, and the material of the isolation layer including one of the following: hafnium dioxide, hexagonal boron nitride, and silicon oxide.

[0070] Taking the structure of the three electrode layers and two resistor switch layers shown in the above structure 400 as an example, Figure 5 further illustrates the positional relationship between the isolation layer and the electrode layer.

[0071] Figure 5 schematically shows a front view of a hexagonal boron nitride-based complementary resistive switch structure including an isolation layer according to an embodiment of the present disclosure.

[0072] As shown in Figure 5, the structure 500 includes a substrate 510, an isolation layer 540, a first electrode layer 521, a second electrode layer 522, a third electrode layer 523, a first resistor switch layer 531, and a second resistor switch layer 532.

[0073] According to embodiments of this disclosure, placing an isolation layer between the substrate and the bottommost electrode layer can effectively prevent leakage current and ensure electrical insulation between the first electrode layer and the substrate. The shape of the isolation layer is not limited, but it needs to cover the overlapping area of ​​the substrate and the electrode layer. The isolation layer can be an insulating material such as hafnium dioxide, hexagonal boron nitride, or silicon oxide.

[0074] According to embodiments of this disclosure, the switching state includes on and off. The switching state of the resistor switch layer is switched by adjusting the potential difference between the first electrode layer and the third electrode layer, including: when the potential of the third electrode layer is higher than the potential of the first electrode layer and the potential difference between the third electrode layer and the first electrode layer is greater than a first threshold, the resistance of the first resistor switch layer decreases until the first resistor switch layer is turned on, and the resistance of the second resistor switch layer increases until the second switch resistor layer is turned off; when the potential of the first electrode layer is higher than the potential of the third electrode layer and the potential difference between the first electrode layer and the third electrode layer is greater than a second threshold, the resistance of the second resistor switch layer decreases until the second resistor switch layer is turned on, and the resistance of the first resistor switch layer increases until the first resistor switch layer is turned off.

[0075] According to embodiments of this disclosure, in the case of a single-layer resistor switch layer, the first overlapping region corresponds to the first resistor switch layer and the second overlapping region corresponds to the second resistor switch layer, which will not be elaborated further here.

[0076] Figure 6 schematically illustrates the voltage-current curves of a complementary resistive switch based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0077] As shown in Figure 6, the horizontal axis represents voltage, and the vertical axis represents current. By applying different voltages, the current of the complementary resistor switch changes accordingly.

[0078] According to embodiments of this disclosure, a bias voltage signal is applied to the first electrode layer and the third electrode layer by an external circuit to adjust the potential of the two electrode layers. When the potential difference reaches different thresholds, the first resistor switch layer and the second resistor switch layer can switch to different resistance values, thereby realizing multi-level storage of multiple switching states.

[0079] According to an embodiment of this disclosure, the switching state of the first resistor switch layer and the switching state of the second resistor switch layer are obtained by the following steps: performing a voltage scan on the first electrode layer and the third electrode layer according to a predetermined voltage range to obtain current data of the first electrode layer or current data of the third electrode layer; and determining the switching state of the first resistor switch layer and the switching state of the second resistor switch layer based on the current data of the first electrode layer or the current data of the third electrode layer.

[0080] According to embodiments of this disclosure, the range of the predetermined voltage range includes a first threshold and a second threshold. By voltage scanning, current data through the first electrode layer and current data through the third electrode layer are measured. The switching state of the resistor switch layer is determined based on whether there is a sudden change in the current. Alternatively, the collected current data can be integrated into a current-voltage characteristic curve, and the resistance value of the first resistor switch layer and the resistance value of the second resistor switch layer can be determined based on the curve.

[0081] For example, when there is a sudden increase in current, it indicates that the corresponding resistor switch's resistor layer changes from a high-resistance state to a low-resistance state, that is, the switch state changes from cutoff to conduction.

[0082] According to embodiments of this disclosure, the switching states of the first and second resistor switching layers are obtained by the following steps: applying a first test bias voltage to the second and third electrode layers to obtain first current data flowing through the second and third electrode layers; applying a second test bias voltage to the second and first electrode layers to obtain second current data flowing through the second and first electrode layers; determining the resistance values ​​of the first and second resistor switching layers based on the first and second current data; and determining the switching states of the first and second resistor switching layers based on the resistance values ​​of the first and second resistor switching layers.

[0083] According to embodiments of this disclosure, current data of the electrode layer can also be read by applying a bias voltage without voltage scanning.

[0084] According to an embodiment of this disclosure, when a first test bias voltage is applied to the second electrode layer and the third electrode layer, the current flowing through the second electrode layer and the third electrode layer is equal, so the first current data can be obtained by reading the current of the second electrode layer or the current of the third electrode layer.

[0085] According to embodiments of this disclosure, when a second test bias voltage is applied to the second electrode layer and the first electrode layer, the current flowing through the second electrode layer and the first electrode layer is equal. Therefore, the second current data can be obtained by reading the current of the second electrode layer or the current of the first electrode layer.

[0086] According to embodiments of this disclosure, Ohm's law is used to determine the resistance values ​​of the first and second resistor switching layers based on first and second current data, thereby determining the switching state.

[0087] To better demonstrate that the complementary resistive switch structure based on hexagonal boron nitride has a larger on / off ratio compared to resistive switch layers made of other materials, the on / off ratios of resistive switch layers made of different materials will be compared below using Figure 7.

[0088] Figure 7 schematically illustrates a comparison of the on / off ratio versus threshold voltage ratio of the complementary resistive switch structure based on hexagonal boron nitride according to embodiments of the present disclosure with complementary resistive switches of other material resistive switch layers.

[0089] As shown in Figure 7, the comparison shows that, compared with complementary resistor switches made of other materials, the complementary resistor switch based on hexagonal boron nitride has a smaller threshold voltage and a larger switching size, which is beneficial for realizing large-scale cross-memristor arrays.

[0090] Figure 8 schematically illustrates a flowchart of a method for fabricating a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0091] As shown in Figure 8, the method 800 includes operations S810 to S830.

[0092] In the S810 operation, an electrode layer is formed on the substrate using electron beam lithography and electron beam evaporation techniques.

[0093] In operation of S820, a resistive switch layer is formed above the electrode layer.

[0094] In operation S830, the remaining electrode layers continue to be formed above the resistive switch layer.

[0095] According to the embodiments of this disclosure, the specific fabrication process of the complementary resistor switch structure of the above embodiment 400 can be illustrated using Figure 9 below.

[0096] Figure 9 schematically illustrates the fabrication process of a complementary resistive switch structure based on hexagonal boron nitride according to an embodiment of the present disclosure.

[0097] As shown in Figure 9, a first electrode layer is formed on the substrate using electron beam lithography and electron beam evaporation. A second resistance switch layer is formed on the first electrode layer using CVD (chemical vapor deposition) or mechanical lift-off. A second electrode layer is formed on the second resistance switch layer using electron beam lithography and electron beam evaporation. The first electrode layer and the second electrode layer are required to have at least partial spatial overlap. A first resistance switch layer is formed on the second electrode layer using CVD or mechanical lift-off. A third electrode layer is formed on the first resistance switch layer using electron beam lithography and electron beam evaporation.

[0098] According to the embodiments of this disclosure, the specific fabrication process of the complementary resistor switch structure of the above embodiment 100 can be illustrated using Figure 10 below.

[0099] Figure 10 schematically illustrates the fabrication process of a complementary resistive switch structure based on hexagonal boron nitride according to another embodiment of the present disclosure.

[0100] As shown in Figure 10, a second electrode layer is formed on the substrate using electron beam lithography and electron beam evaporation. A first resistive switch layer is formed on the second electrode layer using CVD or mechanical lift-off. A first electrode layer and a third electrode layer are formed on the first resistive switch layer using electron beam lithography and electron beam evaporation. The second electrode layer is required to have at least partial spatial overlap with the first and third electrode layers, and the first resistive switch layer is used for isolation. There is no short circuit between the first and third electrode layers.

[0101] It should be noted that the preparation method of the complementary resistive switch structure based on hexagonal boron nitride in the embodiments of this disclosure corresponds to the complementary resistive switch structure based on hexagonal boron nitride in the embodiments of this disclosure. The specific description of the preparation method is referred to in the structure section, and will not be repeated here.

[0102] According to embodiments of this disclosure, an electrode layer is formed on a substrate using electron beam lithography and electron beam evaporation, and a resistive switch layer is formed between the electrode layers to isolate the electrode layers, thereby obtaining a target complementary resistive switch. An external circuit is used to apply a bias voltage signal to the first and third electrode layers to adjust their potentials, thereby changing the switching state of the resistive switch layer to achieve non-volatile storage of the resistance value. Using hexagonal boron nitride as the material for the resistive switch layer reduces the threshold voltage required for switching the resistive switch layer while increasing the device's on / off ratio, which is beneficial for realizing large-scale cross-memristor arrays. Simultaneously, the thickness of the resistive switch layer is only 0.5nm to 10nm, thus reducing the thickness of the resistive switch layer compared to complementary resistive switches in related technologies, thereby compressing the device size and reducing the chip area for three-dimensional integration of memristor arrays. Furthermore, two-dimensional hexagonal boron nitride has a certain degree of ductility, making it suitable for flexible applications such as wearable devices.

[0103] Figure 11 schematically illustrates a block diagram of a memristor array according to an embodiment of the present disclosure.

[0104] As shown in Figure 11, the memristor array 1100 includes a complementary resistor switch 1110.

[0105] It should be noted that the complementary resistor switch 1110 in the memristor array in the embodiments of this disclosure is the same as the complementary resistor switch structure based on hexagonal boron nitride in the above embodiments of this disclosure. For a detailed description of the complementary resistor switch 1110 in the memristor array, please refer to the above embodiments section, and it will not be repeated here.

[0106] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions. Those skilled in the art will understand that the features described in the various embodiments of the present disclosure can be combined and / or combined in various ways, even if such combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments of this disclosure may be combined and / or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0107] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A complementary resistive switch structure based on hexagonal boron nitride, characterized in that, include: Substrate; An electrode layer, located above the substrate, includes a first electrode layer, a second electrode layer, and a third electrode layer. The first electrode layer and the third electrode layer are electrically connected to an external circuit, and the potentials of the first electrode layer and the third electrode layer change with the bias voltage signal received from the external circuit. A resistor switch layer, including a first resistor switch layer, wherein the first resistor switch layer is located between the first electrode layer and the second electrode layer; The substrate, the electrode layer, and the resistor switch layer overlap at least partially in space. The switching state of the resistor switch layer is switched by adjusting the potential difference between the first electrode layer and the third electrode layer. The material of the resistor switch layer includes hexagonal boron nitride, and the thickness of the resistor switch layer is 0.5 nm to 10 nm.

2. The structure according to claim 1, characterized in that, The first electrode layer and the third electrode layer are located side by side on the same side of the first resistive switch layer.

3. The structure according to claim 1, characterized in that, The resistor switch layer further includes a second resistor switch layer located between the second electrode layer and the third electrode layer.

4. The structure according to claim 3, characterized in that, The switching state includes on and off. The switching state of the resistive switch layer is switched by adjusting the potential difference between the first electrode layer and the third electrode layer, including: When the potential of the third electrode layer is higher than that of the first electrode layer and the potential difference between the third electrode layer and the first electrode layer is greater than a first threshold, the resistance of the first resistor switch layer decreases until the first resistor switch layer is turned on, and the resistance of the second resistor switch layer increases until the second switch resistor layer is turned off. When the potential of the first electrode layer is higher than that of the third electrode layer and the potential difference between the first electrode layer and the third electrode layer is greater than the second threshold, the resistance of the second resistor switch layer decreases until the second resistor switch layer is turned on, and the resistance of the first resistor switch layer increases until the first resistor switch layer is turned off.

5. The structure according to claim 3, characterized in that, The switching states of the first resistor switch layer and the second resistor switch layer are obtained according to the following steps: According to a predetermined voltage range, voltage scanning is performed on the first electrode layer and the third electrode layer to obtain current data of the first electrode layer or current data of the third electrode layer. Based on the current data of the first electrode layer or the current data of the third electrode layer, determine the switching state of the first resistor switch layer and the switching state of the second resistor switch layer.

6. The structure according to claim 3, characterized in that, The switching states of the first resistor switch layer and the second resistor switch layer are obtained according to the following steps: A first test bias voltage is applied to the second electrode layer and the third electrode layer to obtain first current data flowing through the second electrode layer and the third electrode layer; A second test bias voltage is applied to the second electrode layer and the first electrode layer to obtain second current data flowing through the second electrode layer and the first electrode layer; Based on the first current data and the second current data, determine the resistance value of the first resistor switch layer and the resistance value of the second resistor switch layer; The switching states of the first resistor switch layer and the second resistor switch layer are determined based on the resistance values ​​of the first resistor switch layer and the second resistor switch layer.

7. The structure according to claim 3, characterized in that, Also includes: An isolation layer is located between the substrate and each of the electrode layers adjacent to the substrate, the isolation layer covering the overlapping area of ​​the substrate and each of the electrode layers adjacent to the substrate, and the material of the isolation layer includes one of the following: hafnium dioxide, hexagonal boron nitride, and silicon oxide.

8. A method for fabricating a complementary resistive switch structure based on hexagonal boron nitride, characterized in that, include: Electron beam lithography and electron beam evaporation techniques are used to form an electrode layer on a substrate; A resistive switch layer is formed above the electrode layer; The remaining electrode layers are then formed above the resistive switch layer; The material of the resistive switch layer includes hexagonal boron nitride.

9. The method according to claim 8, characterized in that, The formation of a resistive switch layer above the electrode layer includes: The resistive switch layer, made of hexagonal boron nitride, is formed on the electrode layer using chemical vapor deposition or mechanical exfoliation.

10. A memristor array, characterized in that, include: The complementary resistive switch structure based on hexagonal boron nitride according to any one of claims 1 to 8.

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