A method for designing a threshold gating device, a threshold gating device, and a dynamic memory

Abstract

The present application discloses a method for designing a threshold gate device, a threshold gate device, and a dynamic memory, relating to the technical field of memories. The method includes: testing the holding voltage, low-resistance state resistance, and threshold voltage of a threshold gate functional layer; determining the target holding voltage of the threshold gate device according to the threshold voltage; determining the sum of the resistances of the upper electrode and the lower electrode of the threshold gate device according to the holding voltage, low-resistance state resistance of the threshold gate functional layer, and the target holding voltage of the threshold gate device; and selecting the materials and thin film parameters of the upper electrode and the lower electrode according to the sum of the resistances of the upper electrode and the lower electrode of the threshold gate device to design a threshold gate device that meets the target holding voltage. The present invention can adjust the target holding voltage of the threshold gate device by changing the sum of the resistances of the upper and lower electrodes, and design a threshold gate device that meets different holding voltages.

Description

Technical Field

[0001] The present application relates to the technical field of memories, and particularly to a method for designing a threshold gating device, a threshold gating device, and a dynamic random access memory (DRAM). Background Art

[0002] The two-way threshold conversion device OTS (Ovonic Threshold Switch) can achieve threshold conversion under the control of an externally applied electrical signal. The specific process is as follows: When an electrical signal is applied to the gating device unit and exceeds the threshold voltage, the material changes from a high-resistance state to a low-resistance state, and the device is in an on state at this time; then, when the applied electrical signal is reduced, and when the signal is less than the holding voltage, the material changes from the low-resistance state back to the high-resistance state, and the device is in an off state. If the transistors in DRAM are replaced with threshold conversion devices, since the threshold conversion device is a two-port device, the peripheral circuit consumes less power and is easy to stack three-dimensionally, which can greatly improve the storage density. The holding voltage of the threshold gating device determines the write operation window of the DRAM. However, the academic community has always believed that the holding voltage is an inherent characteristic of the threshold gating device and there is no way to adjust it, thus limiting the improvement of DRAM performance. Summary of the Invention

[0003] The purpose of the present application is to provide a method for designing a threshold gating device, a threshold gating device, and a dynamic random access memory, which can design a threshold gating device that meets different holding voltages.

[0004] To achieve the above purpose, the present application provides the following solutions:

[0005] In a first aspect, the present application provides a method for designing a threshold gating device, including:

[0006] Testing the holding voltage, low-resistance state resistance, and threshold voltage of the threshold gating functional layer;

[0007] Determining the target holding voltage of the threshold gating device according to the threshold voltage;

[0008] Determining the sum of the resistances of the upper electrode and the lower electrode of the threshold gating device according to the holding voltage, low-resistance state resistance of the threshold gating functional layer, and the target holding voltage of the threshold gating device;

[0009] Selecting the materials and film parameters of the upper electrode and the lower electrode according to the sum of the resistances of the upper electrode and the lower electrode of the threshold gating device to design a threshold gating device that meets the target holding voltage.

[0010] Optionally, the target holding voltage of the threshold gating device is less than or equal to the threshold voltage of the threshold gating functional layer.

[0011] Optionally, the expression for determining the sum of the resistances of the upper electrode and the lower electrode of the threshold gating device is:

[0012] R = (V Hold - V hold ) * R _low / V hold ;

[0013] In the formula, R is the sum of the resistances of the upper electrode and the lower electrode; V Hold is the target holding voltage of the threshold gating device; V hold is the holding voltage of the threshold gating functional layer; R _low is the low-resistance state resistance of the threshold gating functional layer.

[0014] Optionally, the materials of the upper electrode and the lower electrode include at least one of C, Al, Co, Ni, Pt, Au, Ag, Cu, Wu, and Pd.

[0015] In a second aspect, the present application provides a threshold gating device designed based on the above-mentioned threshold gating device design method, including: a threshold gating functional layer, an upper electrode, and a lower electrode; one end of the threshold gating functional layer is connected to the upper electrode, and the other end of the threshold gating functional layer is connected to the lower electrode;

[0016] The threshold gating functional layer has two states: a high-resistance state and a low-resistance state; when the voltage across the threshold gating functional layer exceeds the threshold voltage of the threshold gating functional layer, the threshold gating functional layer switches from the high-resistance state to the low-resistance state; when the voltage across the threshold gating functional layer in the low-resistance state is lower than the holding voltage of the threshold gating functional layer, the threshold gating functional layer switches from the low-resistance state to the high-resistance state.

[0017] Optionally, when the threshold gating functional layer is in the high-resistance state, the threshold voltage of the threshold gating device is the same as the threshold voltage of the threshold gating functional layer.

[0018] Optionally, the materials of the threshold gating functional layer include OTS-based materials, conductive bridge-type materials, and metal-insulator transition-type materials.

[0019] Optionally, the OTS-based materials include: Se-based compound systems, Te-based compound systems, and S-based compound systems.

[0020] In a third aspect, the present application provides a dynamic memory, including: a threshold gating device and a capacitor connected in series; the threshold gating device is the above-mentioned threshold gating device; the end of the threshold gating device not connected to the capacitor is the input end of the dynamic memory; the end of the capacitor not connected to the threshold gating device is the output end of the dynamic memory.

[0021] Optionally, the lower limit of the write operation window of the dynamic memory is the threshold voltage of the threshold strobe device, and the upper limit is the sum of the threshold voltage of the threshold strobe device and the target holding voltage.

[0022] According to the specific embodiments provided by the present application, the following technical effects are disclosed in the present application:

[0023] The present application provides a method for designing a threshold strobe device, a threshold strobe device, and a dynamic memory. Among them, the holding voltage, low-resistance state resistance, and threshold voltage of the threshold strobe functional layer are tested; the target holding voltage of the threshold strobe device is determined according to the threshold voltage; the sum of the resistances of the upper electrode and the lower electrode of the threshold strobe device is determined according to the holding voltage, low-resistance state resistance of the threshold strobe functional layer, and the target holding voltage of the threshold strobe device; the materials and thin film parameters of the upper electrode and the lower electrode are selected according to the sum of the resistances of the upper electrode and the lower electrode of the threshold strobe device to design a threshold strobe device that meets the target holding voltage. The present invention can pre-determine the target holding voltage required for the threshold strobe device, and then calculate the threshold strobe device that meets the corresponding target holding voltage in combination with the holding voltage and low-resistance state resistance of the threshold strobe functional layer. Obviously, different target holding voltages of the threshold strobe device can be achieved by different sums of the resistances of the upper and lower electrodes. Then, the target holding voltage of the threshold strobe device can be adjusted by changing the sum of the resistances of the upper and lower electrodes, and a threshold strobe device that meets different holding voltages can be designed. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic flow chart of a method for designing a threshold strobe device provided in Embodiment 1 of the present application;

[0026] Figure 2 It is a schematic structural diagram of a threshold strobe device provided in Embodiment 2 of the present application;

[0027] Figure 3 It is a schematic diagram based on which the expression for regulating the total holding voltage V Hold of the threshold strobe device provided in Embodiment 2 of the present application is based;

[0028] Figure 4 It is a schematic diagram of the current change through the threshold strobe device after applying a triangular wave across the threshold strobe device provided in Embodiment 2 of the present application;

[0029] Figure 5In Example 1 provided in Embodiment 2 of this application, after applying a triangular wave with a peak value of 6V and a duration of 240ns across the threshold strobe device, the simulation diagram of the current change through the threshold strobe device and the holding voltage V of the threshold strobe device Hold Schematic diagram;

[0030] Figure 6 In Example 2 provided in Embodiment 2 of this application, after applying a triangular wave with a peak value of 6V and a duration of 240ns across the threshold strobe device, the simulation diagram of the current change through the threshold strobe device and the holding voltage V of the threshold strobe device Hold Schematic diagram;

[0031] Figure 7 Schematic diagram of the structure of a 1S1C dynamic memory composed of threshold strobe devices provided in Embodiment 3 of this application.

[0032] Reference numerals: 1 - upper electrode; 2 - threshold strobe functional layer; 3 - lower electrode. Detailed implementation manners

[0033] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0034] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0035] Embodiment 1

[0036] As Figure 1 shown, this embodiment provides a design method for a threshold strobe device, including the following steps S1 to S4.

[0037] Step S1, measure the holding voltage V hold , low-resistance state resistance R _low and threshold voltage V th of the threshold strobe functional layer 2.

[0038] Step S2, determine the target holding voltage V th of the threshold strobe device according to the threshold voltage V Hold . Among them, the target holding voltage V Hold of the threshold strobe device is less than or equal to the threshold voltage V th of the threshold strobe functional layer 2.

[0039] Step S3, determine the sum of the resistances of the upper electrode 1 and the lower electrode 3 of the threshold switching device according to the holding voltage of the functional layer 2, the low-resistance state resistance, and the target holding voltage of the threshold switching device.

[0040] Step S4, select suitable materials for the upper electrode 1 and the lower electrode 3 according to the sum of the resistances of the upper electrode 1 and the lower electrode 3 of the threshold switching device, and then adjust their manufacturing processes to obtain film parameters that meet the resistance value requirements, so that the sum of the resistances of the upper electrode 1 and the lower electrode 3 meets the result calculated in Step S3, and finally design a threshold switching device that meets the target holding voltage. Among them, the film parameters include the manufacturing parameters of the film, as well as the doping, thickness, elemental composition, etc. of the film itself. The adjustment means are conventional adjustment means, and the purpose is to make the film reach the target resistance value.

[0041] As an optional implementation manner, the expression for determining the sum of the resistances of the upper electrode 1 and the lower electrode 3 of the threshold switching device is:

[0042] R = (V Hold - V hold ) * R _low / V hold ;

[0043] In the formula, R is the sum of the resistances of the upper electrode 1 and the lower electrode 3; V Hold is the target holding voltage of the threshold switching device; V hold is the holding voltage of the threshold switching functional layer 2; R _low is the low-resistance state resistance of the threshold switching functional layer 2.

[0044] As an optional implementation manner, the materials of the upper electrode 1 and the lower electrode 3 include at least one of C, Al, Co, Ni, Pt, Au, Ag, Cu, Wu, Pd, so as to adjust different sums of the upper and lower electrode resistances.

[0045] In this embodiment, a method for regulating the holding voltage of a threshold switching device is provided, which expands the application scenarios of the threshold switching device. Specifically, by adjusting the sum of the resistances of the upper and lower electrodes, the holding voltage V Hold of the threshold switching device can be adjusted, breaking the view that "the holding voltage of the threshold switching device is an inherent characteristic of the threshold switching device and cannot be adjusted", and the performance of DRAM can be improved based on the adjustability of the holding voltage of the threshold switching device.

[0046] Embodiment 2

[0047] As Figure 2As shown in the figure, this embodiment provides a threshold strobing device, which is designed based on the threshold strobing device design method described in Embodiment 1, and includes: a threshold strobing functional layer 2, an upper electrode 1, and a lower electrode 3; one end of the threshold strobing functional layer 2 is connected to the upper electrode 1, and the other end of the threshold strobing functional layer 2 is connected to the lower electrode 3.

[0048] As an alternative implementation, the material of the threshold strobing functional layer 2 includes OTS-based materials, conductive bridge-type materials, and metal-insulator transition-type materials.

[0049] As an alternative implementation, the OTS-based materials are composed of chalcogenide compounds, and its main material systems have three categories: Se-based compound systems, Te-based compound systems, and S-based compound systems.

[0050] The threshold strobing functional layer 2 has two states: a high-resistance state and a low-resistance state; when the voltage across the threshold strobing functional layer 2 exceeds the threshold voltage of the threshold strobing functional layer 2, the threshold strobing functional layer 2 switches from the high-resistance state to the low-resistance state; when the voltage across the threshold strobing functional layer 2 in the low-resistance state is lower than the holding voltage of the threshold strobing functional layer 2, the threshold strobing functional layer 2 switches from the low-resistance state to the high-resistance state. Utilizing this characteristic of the threshold strobing functional layer 2, by adjusting the sum of the resistances of the upper and lower electrodes, the total holding voltage V of this threshold strobing device can be regulated. Hold , thereby improving the operation window of its 1S1C dynamic memory.

[0051] Among them, the holding voltage V of the threshold strobing device Hold = V hold + I hold * R, where R is the sum of the resistances of the upper electrode 1 and the lower electrode 3. Figure 3 shows the positive linear relationship presented between the holding voltage V of the threshold strobing device Hold and the sum of the resistances of the upper and lower electrodes R. The greater the sum of the resistances of the upper and lower electrodes, the more obvious the positive regulation effect on V Hold . Among them, I hold = V hold / R _low , where R _low is the low-resistance state resistance value of the threshold strobing functional layer 2. The value range of R is 0 ≤ R ≤ R max , where R max is the value of R when V Hold is equal to V th . By adjusting the resistance value of R, the holding voltage V of the threshold strobing device Hold can be adjusted.

[0052] Further preferably, the threshold strobing device has a threshold voltage V TH, because when the threshold-storage functional layer 2 is in a high-resistance state, the current passing through the threshold-storage device is very small. Therefore, the voltage division between the upper electrode 1 and the lower electrode 3 can be neglected. Thus, the threshold voltage V of the threshold-storage device TH is basically the same as the threshold voltage V of the threshold-storage functional layer 2 th and is not affected by the resistances of the upper electrode 1 and the lower electrode 3.

[0053] Apply a voltage waveform as shown Figure 4 across the threshold-storage device. At the initial moment, the applied voltage is less than the threshold voltage V of the threshold-storage functional layer 2 th . The threshold-storage functional layer 2 is in a high-resistance state, and at this time, there is a very small current passing through the circuit. Figure 4 It is shown in that there is no current passing through the circuit, and the weak current in the circuit when the threshold-storage functional layer 2 is in a high-resistance state is ignored; when the voltage rises to be greater than the threshold voltage V of the threshold-storage functional layer 2 th , the threshold-storage functional layer 2 switches from a high-resistance state to a low-resistance state, and the current in the circuit suddenly increases and changes with the change of the applied voltage; when the voltage drops to be less than the holding voltage V of the threshold-storage functional layer 2 hold , the threshold-storage functional layer 2 switches from a low-resistance state to a high-resistance state, and the current in the circuit suddenly decreases and is approximately zero.

[0054] Since there is approximately no current passing through the circuit before the applied voltage rises to V th , the total threshold voltage V of the threshold-storage device TH is equal to the threshold voltage V of the threshold-storage functional layer 2 th , that is, adjusting the sum of the resistances of the upper and lower electrodes will not affect the magnitude of V TH ; while there is a large on-state current in the circuit before the applied voltage drops to V hold , so the total holding voltage V of the threshold-storage device Hold is equal to the sum of the holding voltage V of the threshold-storage functional layer 2 hold and the voltage division of the upper and lower electrodes, that is, V Hold can be regulated by adjusting the sum of the resistances of the upper and lower electrodes. The specific regulation method is as follows:

[0055] When it is necessary to increase the holding voltage V of the threshold-storage device Hold , select and adjust the materials of the upper and lower electrodes from C, Al, Co, Ni, Pt, Au, Ag, Cu, Wu, Pd to increase the sum of the resistances of the upper and lower electrodes R1 + R2; when the voltage across the threshold-storage functional layer 2 is equal to V hold , the on-state current in the circuit is I hold . At this time, the voltage division of the upper and lower electrodes increases, making the total holding voltage V of this threshold-storage device Hold increase.

[0056] When it is necessary to reduce the holding voltage V of the threshold-storage device Hold , select and adjust the materials of the upper and lower electrodes from C, Al, Co, Ni, Pt, Au, Ag, Cu, Wu, Pd to reduce the sum of the resistances of the upper and lower electrodes R1+R2; when the voltage across the threshold-storage functional layer 2 is equal to V hold , the on-state current in the circuit is I hold , at this time the voltage division of the resistances of the upper and lower electrodes decreases, so that the total holding voltage V of this threshold-storage device Hold decreases.

[0057] The following further illustrates with examples that V Hold can be regulated by adjusting the sum of the resistances of the upper and lower electrodes.

[0058] Example 1:

[0059] A threshold-storage device, the threshold voltage of the threshold-storage functional layer 2 is 3V, the holding voltage is 1.2V, and the on-state current at the holding voltage is 6mA. Adjust the sum of the resistances of the upper and lower electrodes to 100Ω. Apply a triangular wave with a peak value of 6V and a duration of 240ns across the threshold-storage device: initially, the threshold-storage functional layer 2 is in a high-resistance state, and the current passing through is very small. At this time, the voltage across the threshold-storage functional layer 2 is approximately equal to the applied voltage across the threshold-storage device; when the voltage across the threshold-storage functional layer 2 increases to 3V, the threshold-storage functional layer 2 switches from the high-resistance state to the low-resistance state, the current increases, and the resistances of the upper and lower electrodes start to divide the voltage; when Vs gradually decreases, so that the voltage across the threshold-storage functional layer 2 decreases to 1.2V, the on-state current passing through the circuit is 6mA, the voltage division of the upper and lower electrodes is 0.6V, and the total holding voltage V of the threshold-storage device Hold =1.8V, as shown in Figure 5 .

[0060] Example 2:

[0061] A threshold gating device, the threshold voltage of the threshold gating functional layer 2 is 3V, the holding voltage is 1.2V, the on-state current at the holding voltage is 6mA, and the sum of the resistances of the upper and lower electrodes is adjusted to 200Ω. A triangular wave with a peak value of 6V and a duration of 240ns is applied across the threshold gating device: Initially, the threshold gating functional layer 2 is in a high-resistance state, and the current passing through is very small. At this time, the voltage across the threshold gating functional layer 2 is approximately equal to the applied voltage Vs across the threshold gating device; when the voltage across the threshold gating functional layer 2 increases to 3V, the threshold gating functional layer 2 switches from the high-resistance state to the low-resistance state, the current increases, and the upper and lower electrodes start to divide the voltage; when Vs gradually decreases such that the voltage across the threshold gating functional layer 2 decreases to 1.2V, the on-state current through the circuit is 6mA, the upper and lower electrodes divide the voltage by 1.2V, and the total holding voltage V Hold = 2.4V, as Figure 6 shown.

[0062] In this embodiment, a threshold gating device is provided. By adjusting the sum of the resistances of the upper and lower electrodes, the holding voltage of the threshold gating device can be changed. Therefore, the required holding voltage of the threshold gating device can be flexibly regulated according to requirements, realizing the regulation of the holding voltage of the threshold gating device, breaking the view that "the holding voltage of the threshold gating device is an inherent characteristic of the threshold gating device and there is no way to adjust it", and the performance of DRAM can be improved based on the adjustable holding voltage of the threshold gating device.

[0063] Embodiment 3

[0064] As Figure 7 shown, this embodiment provides a dynamic random access memory, including: a threshold gating device and a capacitor connected in series; the threshold gating device is the threshold gating device described in Embodiment 2; the end of the threshold gating device not connected to the capacitor is the input end of the dynamic random access memory; the end of the capacitor not connected to the threshold gating device is the output end of the dynamic random access memory.

[0065] Among them, the lower limit of the write operation window of the dynamic random access memory is the threshold voltage of the threshold gating device, and the upper limit is the sum of the threshold voltage of the threshold gating device and the target holding voltage. Therefore, the write operation window of the dynamic random access memory can be increased by increasing the sum of the resistances R of the upper electrode 1 and the lower electrode 3.

[0066] Taking two examples in Embodiment 2 as an illustration, it can be shown that the write window of a dynamic memory can be increased by increasing the sum of the resistances R of the upper electrode 1 and the lower electrode 3. A threshold strobe device has a threshold voltage of 3V for the threshold strobe functional layer 2, a holding voltage of 1.2V, an on-state current of 6 mA at the holding voltage, and the sum of the resistances of the upper and lower electrodes is 100 Ω. A triangular wave with a peak value of 6V and a duration of 240 ns is applied across the threshold strobe device. When the applied voltage gradually decreases such that the voltage across the threshold strobe functional layer 2 drops to 1.2V, the on-state current through the circuit is 6 mA, the voltage drop across the upper and lower electrodes is 0.6V, and the total holding voltage V Hold of the threshold strobe device is 1.8V. For a 1S1C dynamic memory composed of this threshold strobe device, the lower limit of its write operation window is V TH , and the upper limit is V TH +V Hold . Therefore, the operation window of the 1S1C dynamic memory is 1.8V.

[0067] Now, adjust the sum of the resistances of the upper and lower electrodes to 200 Ω. Still apply a triangular wave with a peak value of 6V and a duration of 240 ns across the threshold strobe device. When the applied voltage gradually decreases such that the voltage across the threshold strobe functional layer 2 drops to 1.2V, the on-state current through the circuit is 6 mA, the voltage drop across the upper and lower electrodes is 1.2V, and the total holding voltage V Hold of the threshold strobe device is 2.4V. For a 1S1C dynamic memory composed of this threshold strobe device, the lower limit of its write operation window is V TH , and the upper limit is V TH +V Hold . Therefore, the write operation window of the 1S1C dynamic memory is 2.4V; compared with the write operation window before adjusting the sum of the resistances of the upper and lower electrodes, the space has increased by 0.6V.

[0068] In this embodiment, by adjusting the sum of the resistances of the upper and lower electrodes, the holding voltage of the threshold strobe device can be changed. Further, the write operation window of the 1S1C dynamic memory composed of this threshold strobe device can be increased, thereby improving the anti-interference ability of the dynamic memory to noise and voltage fluctuations, and also contributing to improving the reliability and fault tolerance of the memory and reducing the error rate.

[0069] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0070] In this text, specific examples are used to illustrate the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A method for designing a threshold gating device, characterized in that, Including: Testing the holding voltage, low resistance state resistance and threshold voltage of the threshold selection function layer; Determining the target holding voltage of the threshold selection device according to the threshold voltage; Determining the sum of the resistances of the upper electrode and the lower electrode of the threshold selection device according to the holding voltage, low resistance state resistance of the threshold selection function layer and the target holding voltage of the threshold selection device; Selecting the materials and thin film parameters of the upper electrode and the lower electrode according to the sum of the resistances of the upper electrode and the lower electrode of the threshold selection device to design a threshold selection device that meets the target holding voltage; Wherein, the target holding voltage of the threshold selection device is less than or equal to the threshold voltage of the threshold selection function layer; Wherein, the expression for determining the sum of the resistances of the upper electrode and the lower electrode of the threshold selection device is: R = (V Hold - V hold ) * R _low / V hold ; Wherein, R is the sum of the resistances of the upper electrode and the lower electrode; V Hold is the target holding voltage of the threshold gating device; V hold is the holding voltage of the threshold gating functional layer; R _low is the low-resistance state resistance of the threshold gating functional layer.

2. The threshold gating device design method according to claim 1, wherein The materials of the upper electrode and the lower electrode include at least one of C, Al, Co, Ni, Pt, Au, Ag, Cu, W, Pd.

3. The threshold gating device design method according to claim 1, characterized in that, The threshold selection device includes a threshold selection function layer, an upper electrode and a lower electrode; one end of the threshold selection function layer is connected to the upper electrode, and the other end of the threshold selection function layer is connected to the lower electrode; The threshold selection function layer has two states: a high resistance state and a low resistance state; when the voltage across the threshold selection function layer exceeds the threshold voltage of the threshold selection function layer, the threshold selection function layer switches from the high resistance state to the low resistance state; when the voltage across the low resistance state threshold selection function layer is lower than the holding voltage of the threshold selection function layer, the threshold selection function layer switches from the low resistance state to the high resistance state.

4. The threshold gating device design method according to claim 3, characterized in that When the threshold selection function layer is in the high resistance state, the threshold voltage of the threshold selection device is the same as the threshold voltage of the threshold selection function layer.

5. The threshold strobe device design method according to claim 3, wherein The materials of the threshold selection function layer include OTS-based materials, conductive bridge-type materials and metal-insulator transition-type materials.

6. The threshold gating device design method according to claim 5, characterized in that The OTS-based materials include: Se-based compound systems, Te-based compound systems and S-based compound systems.

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