Photoelectric memristor with switchable volatile / non-volatile function and preparation method thereof

Abstract

The invention provides a volatile / non-volatile function switchable photoelectric memristor and a preparation method thereof, which adopt a two-end structure and sequentially comprise a top electrode layer (100), a resistive layer (110) and a bottom electrode layer (120) from top to bottom, the switchable photoelectric memristor has different functions, and the switchable photoelectric memristor is switched to be in a volatile characteristic or a non-volatile characteristic through different voltages applied to the top electrode layer. The photoelectric memristor can be switched to be in a volatile characteristic or a non-volatile characteristic by applying different illumination intensities under a small voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of memristors, in particular to a photoelectric memristor with switchable volatile / non-volatile functions and a preparation method thereof. Background Art

[0002] Neuromorphic devices show great potential in overcoming the bottleneck of the von Neumann architecture and expanding the boundaries of artificial intelligence. As a multi-functional information integration and processing unit, an artificial neuron can effectively integrate external input signals and generate spike signals when the signal intensity exceeds a threshold. It is the core unit for the neuromorphic system to achieve spatio-temporal signal integration and is widely used in neuromorphic computing. At the same time, a true random number generator based on the internal physical mechanism of a memristor plays a key role in the field of information security, especially in encryption and decryption systems, due to its inherent unpredictability. The prior art has not yet been able to effectively implement the functional simulation of a true random number generator and an artificial neuron through a memristor. Summary of the Invention

[0003] Aiming at the actual needs of the prior art, the purpose of the present invention is to provide a photoelectric memristor with switchable volatile / non-volatile functions and a preparation method thereof, realizing the functional simulation of a true random number generator and an artificial neuron.

[0004] To achieve the above object, the present invention adopts the following technical solutions: A photoelectric memristor with switchable volatile / non-volatile functions, the photoelectric memristor adopts a two-terminal structure, and from top to bottom are a top electrode layer (100), a resistance layer (110), and a bottom electrode layer (120) in sequence; by applying different voltages to the top electrode layer (100), the photoelectric memristor switches to a volatile characteristic or a non-volatile characteristic; when the photoelectric memristor is under a small voltage, by applying different light intensities, it switches to a volatile characteristic or a non-volatile characteristic.

[0005] In a preferred embodiment: the top electrode layer (100) is an active electrode with a thickness of 50 - 100 nm.

[0006] In a preferred embodiment: the resistance layer (110) is a MXene quantum dot blended polymer with a thickness of 100 - 200 nm.

[0007] In a preferred embodiment: MXene is a type of two-dimensional transition metal carbide, nitride, or carbonitride, including Ti 3 C 2 、Ti 2 C、V 2 C and Nb 2 C.

[0008] In a preferred embodiment: the bottom electrode layer (120) is silicon with a thickness of 300 - 400 μm.

[0009] In a preferred embodiment: by applying a small voltage to the top electrode layer (100), the optoelectronic memristor exhibits volatile characteristics, simulating a true random number generator and outputting random current peaks; by increasing the applied light intensity, the optoelectronic memristor switches from volatile to non-volatile characteristics.

[0010] In a preferred embodiment: by applying a large voltage to the top electrode layer (100), the optoelectronic memristor exhibits non-volatile characteristics, simulating the integrate-and-fire behavior of artificial neurons, and the burst time is adjustable by the light intensity.

[0011] The present invention also provides a method for preparing an optoelectronic memristor with switchable volatile / non-volatile functions, and prepares the optoelectronic memristor with switchable volatile / non-volatile functions as described above, including the following steps: Step 1: Plasma-treat a silicon substrate with a thickness of 300 μm to 400 μm as the bottom electrode layer; Step 2: Deposit a blend solution film with a thickness of 100 nm to 200 nm on the silicon substrate by solution method, and form a stable film as the resistance layer after annealing; Step 3: Evaporate and deposit a metal electrode with a thickness of 50 nm to 100 nm on the resistance layer by mask evaporation deposition using vacuum evaporation deposition as the top electrode layer.

[0012] In a preferred embodiment: the solution used to deposit a blend solution film with a thickness of 100 nm to 200 nm on the silicon substrate by solution method is a blend solution of MXene quantum dots and polymer, which is obtained by blending MXene quantum dots and polymer in a specific ratio, sonicating in an ice bath and standing in a vacuum environment until clear; deposit the blend solution on the silicon substrate, and then perform annealing treatment in a vacuum environment to obtain the resistance layer.

[0013] Compared with the prior art, the present invention has the following beneficial effects: through the switchable optoelectronic memristor provided by the present invention and its preferred scheme, the functions of artificial neurons and true random number generators are integrated, which not only significantly improves the device utilization rate, but also provides an innovative solution for constructing an integrated system of high-efficiency energy-saving encryption / decryption and intelligent recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural principle diagram of the switchable optoelectronic memristor in Embodiment 1 of the present invention; in the figure: 100 - silver as the top electrode layer; 110 - resistance layer; 120 - silicon substrate as the bottom electrode layer.

[0015] Figure 2 It is the electrical transfer characteristic curve of the switchable optoelectronic memristor in Example 1 of the present invention under volatile conditions; Figure 3 It is the current output diagram of the switchable optoelectronic memristor in Example 1 of the present invention under continuous electrical pulses in the working mode of a true random number generator; Figure 4 It is the electrical transfer characteristic curve of the switchable optoelectronic memristor in Example 1 of the present invention under non-volatile conditions; Figure 5 It is the current output diagram of the switchable optoelectronic memristor in Example 1 of the present invention under continuous electrical pulses in the working mode of an artificial neuron; Figure 6 It is the electrical transfer characteristic curve of the switchable optoelectronic memristor in Example 1 of the present invention under darkness and 365 nm light illumination; Detailed implementation manners

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanations for the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0018] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0019] The present invention provides a preferred optoelectronic memristor with switchable volatile / non-volatile functions, which adopts a two-terminal structure and sequentially includes a top electrode layer, a resistance layer, and a bottom electrode layer from top to bottom. The optoelectronic memristor has different functions and can be switched to volatile characteristics or non-volatile characteristics by applying different voltages to the top electrode layer; when a small voltage is applied to the optoelectronic memristor, it can be switched to volatile characteristics or non-volatile characteristics by applying different light intensities. When a large voltage is applied, the memristor exhibits non-volatile characteristics. As Figure 1 shown, 100 is a silver electrode, 110 is a resistance layer obtained by blending PVP and Ti 3 C 2 quantum dots, and 120 is a silicon substrate.

[0020] Ti 3 C 2The quantum dots and PVP are dissolved in ethanol and spin-coated onto the plasma-treated silicon wafer at a speed of 2000 r / min as the resistance layer, and annealed in vacuum at 100 °C for 30 min. Then, a 50-nm metal electrode is deposited on the resistance layer using a mask plate as the top electrode layer, and this is a two-terminal structure switchable optoelectronic memristor.

[0021] Its corresponding preparation method includes the following steps: Step S11: Plasma-treat a silicon substrate with a thickness of 300 μm to 400 μm as the bottom electrode layer Step S12: Prepare a blend solution of Ti 3 C 2 and quantum dots with PVP, ultrasonically treat it in an ice bath, let it stand in vacuum until clear, and filter it through a 220-nm membrane.

[0022] Step S13: Deposit a 100-nm to 200-nm blend solution film on the silicon substrate by the solution method, and form a stable film as the resistance layer after annealing in vacuum Step S14: Use vacuum evaporation deposition to deposit a 50-nm to 100-nm metal electrode on the resistance layer using a mask plate as the top electrode layer, and this is a two-terminal structure switchable optoelectronic memristor.

[0023] To further illustrate the technical effects of the present invention, the following specifically combines Figures 1-6 more specific and different embodiments for illustration.

[0024] Example 1 1) Dissolve 5 mg of Ti 3 C 2 quantum dots and 40 mg of PVP in 2 mL of ethanol. After ultrasonic treatment in an ice bath for 30 min, let it stand in vacuum until clear, and filter it through a 220-nm membrane to obtain a blend solution of PVP and Ti 3 C 2 quantum dots.

[0025] 2) Cut a silicon wafer with a size of 1.4 cm × 1.4 cm and a thickness of 400 μm, clean it successively with acetone, isopropanol, and deionized water for 30 s, then dry it with nitrogen to obtain a clean silicon wafer as the substrate, and treat the surface of the silicon substrate with plasma technology for 15 min.

[0026] 3) In a vacuum environment, deposit the blend solution of PVP and Ti 3 C 2The quantum dot blend solution was spin-coated onto a silicon substrate at a speed of 2000 r / min for 45 s by the spin-coating method, and then the silicon substrate was moved to a heating stage and annealed in a vacuum environment at 100 °C for 30 min to obtain a 200-nm-thick film as the resistive layer of the device.

[0027] 4) A 50-nm-thick silver electrode was deposited on the resistive layer described in 3) by vacuum thermal evaporation using a mask, and this is a two-terminal structure switchable optoelectronic memristor.

[0028] Example 2 1) 8 mg of Ti 3 C 2 quantum dots and 50 mg of PVP were dissolved in 2 mL of ethanol. After ultrasonic treatment in an ice bath for 30 min and filtration through a 220-nm membrane, a blend solution of PVP and Ti 3 C 2 quantum dots was obtained.

[0029] 2) A silicon wafer with a size of 1.5 cm × 1.5 cm and a thickness of 400 μm was cut, sequentially cleaned with acetone, isopropanol, and deionized water for 30 s, and then dried with nitrogen to obtain a clean silicon wafer as the substrate. The surface of the silicon substrate was treated with plasma technology for 15 min.

[0030] 3) In a vacuum environment, the blend solution of PVP and Ti 3 C 2 quantum dots was spin-coated onto the silicon substrate at a speed of 2500 r / min for 45 s by the spin-coating method, and then the silicon substrate was moved to a heating stage and annealed in a vacuum environment at 100 °C for 30 min to obtain a 250-nm-thick film as the resistive layer of the device.

[0031] 4) A 50-nm-thick silver electrode was deposited on the resistive layer described in 3) by vacuum thermal evaporation using a mask, and this is a two-terminal structure switchable optoelectronic memristor.

[0032] The structural diagram and test results of Example 1 are as Figures 1-6 shown. Since Ti 3 C 2Quantum dots have the photovoltaic effect and high electrical conductivity. There are defects on their surfaces that can trap charges, and when the defects are filled with charges, a conductive path can be generated. And active metals as electrodes will also generate silver conductive filaments connecting the upper and lower electrodes under voltage. Therefore, the conduction of the memristor can be changed by regulating the applied voltage and light intensity, so that the working state of the memristor can be switched between volatile and non-volatile. When a small voltage is applied, the memristor exhibits volatile characteristics and can simulate a true random number generator to output random current peaks. By increasing the applied light intensity, the memristor can be switched from volatile to non-volatile characteristics. When a large voltage is applied, the memristor exhibits non-volatile characteristics and can simulate behaviors such as the integration and firing of artificial neurons, and the burst time is adjustable by the light intensity.

[0033] The present invention is not limited to the above-mentioned best implementation mode. Anyone inspired by the present invention can obtain other various forms of a volatile / non-volatile function-switchable optoelectronic memristor and its preparation method. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope covered by the present invention.

Claims

1. A photoelectric memristor with switchable volatile / non-volatile functions, characterized in that: The photoelectric memristor adopts a two-terminal structure, which comprises, from top to bottom, a top electrode layer (100), a resistor layer (110), and a bottom electrode layer (120); by applying different voltages to the top electrode layer (100), the photoelectric memristor switches to a volatile characteristic or a non-volatile characteristic; and by applying different light intensities under a small voltage, the photoelectric memristor switches to a volatile characteristic or a non-volatile characteristic.

2. The photoelectric memristor with switchable volatile / non-volatile functions according to claim 1, characterized in that: The top electrode layer (100) is an active electrode with a thickness of 50-100 nm.

3. The photoelectric memristor with switchable volatile / non-volatile functions according to claim 1, characterized in that: The resistance layer (110) is a MXene quantum dot blended polymer and has a thickness of 100-200 nm.

4. The photoelectric memristor with switchable volatile / non-volatile functions according to claim 3, characterized in that: MXene is specifically a class of two-dimensional transition metal carbides, nitrides or carbonitrides, including Ti3C2, Ti2C, V2C and Nb2C.

5. The photoelectric memristor with switchable volatile / non-volatile functions according to claim 1, characterized in that: The bottom electrode layer (120) is silicon with a thickness of 300-400 μm.

6. The photoelectric memristor with switchable volatile / non-volatile functions according to claim 1, characterized in that: By applying a small voltage to the top electrode layer (100), the photoelectric memristor exhibits volatile characteristics, simulating a true random number generator and outputting random current peaks; by increasing the applied light intensity, the photoelectric memristor switches from volatile to non-volatile characteristics.

7. The photoelectric memristor with switchable volatile / non-volatile functions according to claim 1, characterized in that: By applying a large voltage on the top electrode layer (100), the photomemristor exhibits non-volatile characteristics, simulating the integral firing behavior of artificial neurons, and the burst time is adjustable by light intensity.

8. A method for preparing a photoelectric memristor with switchable volatile / non-volatile functions, characterized in that A photoelectric memristor with volatile / non-volatile function switchable as described in any one of claims 1 to 7 is prepared, comprising the following steps: Step 1: Plasma-treat a silicon substrate with a thickness of 300 μm to 400 μm to serve as a bottom electrode layer; Step 2: depositing a 100 nm to 200 nm blend solution film on the silicon substrate by a solution method, and forming a stable film as a resistance layer after annealing; Step 3: Using a vacuum evaporation deposition method, a metal electrode with a thickness of 50 nm to 100 nm is deposited on the resistor layer using a mask as a top electrode layer.

9. The method for preparing a photoelectric memristor with switchable volatile / non-volatile functions according to claim 8, characterized in that: A 100 nm to 200 nm blended solution film is deposited on the silicon substrate by a solution method. The solution used is a MXene quantum dot and polymer blended solution, which is obtained by blending MXene quantum dots and polymers in a specific ratio, ultrasonicating them in an ice bath, and standing them in a vacuum environment until they are clarified; the blended solution is deposited on the silicon substrate, and then annealed in a vacuum environment to obtain a resistor layer.

Images