A double-layer thin film structure all-optically controlled memristor device and its preparation method

Abstract

The present invention discloses a double-layer thin film structure all-optically controlled memristor device and a preparation method thereof, wherein the all-optically controlled memristor device is composed of SiO 2 Substrate, inert electrode, ZnO thin film layer, MoO x Thin film layer and transparent electrode, the ZnO thin film layer and MoO x The thin film layers together form the photoelectric memristor layer of the all-optically controlled memristor device, forming a heterojunction structure with a certain barrier width. The all-optically controlled memristor device of the present invention can be controlled by adjusting the ZnO / MoO x The barrier width of the heterojunction can realize the reversible activation and inhibition of light gating under the regulation of ultraviolet light and green light. The all-light-controlled memristor device of the present invention is a two-terminal device with simple structure, easy preparation and integrability. The reversible regulation of ultraviolet light and green light can realize the reversible modulation of the device under all-light control. It has good application potential in the research of visual perception storage and computing technology.

Description

Technical Field

[0001] The invention belongs to the technical field of microelectronic materials and devices, and relates to an all-optically controlled memristor device with a double-layer thin film structure and a preparation method thereof. Background Art

[0002] The von Neumann architecture plays a vital role in the development of modern intelligent technology. It provides practical theoretical guidance for the computing architecture of computers, making computer systems an indispensable part of human life. However, with the advent of the intelligent era, in the modern life of data explosion, various artificial intelligence technologies require faster computing speeds, larger storage space and lower computing energy consumption. Gradually, people realized that in the traditional von Neumann architecture, since the unit responsible for information storage and the computing unit responsible for data processing are in a separated state, the processing connection between the two requires a data analog-to-digital conversion (ADC) device to complete, and the information conversion and transmission between independent functional units requires additional time and energy consumption, which limits the improvement of computing efficiency and makes the modern computer computing system consume huge power. This is called the von Neumann bottleneck. Therefore, the development of new sensor computing electronic technology with the ability to avoid data conversion and transmission has become an important goal for researchers. Because memristors have the characteristics of high density, low latency and non-volatility during data processing, this type of electronic component has received widespread attention in the field of storage and computing technology, and has also become an important research direction for researchers. In addition, the introduction of optical and electrical coordinated modulation has also laid a solid foundation for the exploration of memristive devices in the development of integrated sensing, storage and computing technology. However, in the optical modulation of most memristive devices, the optical signal can only excite the device in one direction. If the bidirectional excitation and inhibition functions are to be realized, the introduction of electrical signals is still required, which makes memristive devices still subject to checks and balances in the development of integrated sensing, storage and computing technology. Summary of the invention

[0003] Based on the above technical status, the present invention provides an all-optically controlled memristor device with a double-layer thin film structure and a preparation method thereof, which can achieve excitation and inhibition effects under all-optical conditions.

[0004] The technical solution of the present invention is as follows:

[0005] A double-layer thin film all-optically controlled memristor device, from bottom to top, SiO 2 Substrate, inert electrode, ZnO thin film layer, MoO x Thin film layer, transparent electrode, the ZnO thin film layer and MoO x The thin film layers together constitute the optoelectronic memristor layer of the all-optically controlled memristor device.

[0006] The thickness of the ZnO thin film layer is 100±20nm, and the MoO xThe thickness of the film layer is 100±30nm.

[0007] The inert electrode is W, Pt, etc., and the transparent electrode is ITO, FTO, etc.

[0008] A method for preparing the above-mentioned all-optically controlled memristor device with a double-layer thin film structure comprises the following steps:

[0009] S1, SiO 2 The substrate was ultrasonically cleaned with acetone, ethanol, and deionized water for 8 to 15 minutes in sequence and dried with nitrogen;

[0010] S2, in SiO 2 A W film was deposited on the substrate as the bottom electrode. The growth conditions were: sputtering with a tungsten target at a power of 80 W for 5 minutes in a pure argon environment at room temperature;

[0011] S3, depositing a ZnO film on the W electrode, the growth conditions are: using a zinc oxide target for sputtering at a power of 80 W for 30 minutes in a pure argon environment at room temperature;

[0012] S4. Deposition of MoO on ZnO film x The film growth conditions are as follows: in a pure argon environment at room temperature, a molybdenum oxide target is sputtered at a power of 80 W for 30 minutes to obtain a photoelectric memristor layer;

[0013] S5. Depositing a transparent electrode ITO on the photoelectric memristor layer obtained in step S4, the growth conditions are: using an ITO target for sputtering at a power of 30 W for 2 minutes in a pure argon environment at room temperature.

[0014] In steps S2-S5, the deposition method is magnetron sputtering.

[0015] The all-optically controlled memristor device of the present invention can be controlled by adjusting the ZnO / MoO x The barrier width of the heterojunction can realize the reversible activation and inhibition of light gating under the regulation of ultraviolet light and green light. The all-light-controlled memristor device of the present invention is a two-terminal device with simple structure, easy preparation and integrability. The reversible regulation of ultraviolet light and green light can realize the reversible modulation of the device under all-light control. It has good application potential in the research of visual perception storage and computing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of an all-optically controlled memristor device constructed according to the present invention;

[0017] Figure 2 A flow chart of the preparation of an all-optically controlled memristor device constructed according to the present invention;

[0018] Figure 3A current-voltage (IV) characteristic curve of the initial state of the all-optically controlled memristor device constructed according to the present invention;

[0019] Figure 4 The current-time (It) characteristic curve of the all-light-controlled memristor device constructed according to the present invention under ultraviolet light irradiation;

[0020] Figure 5 The current-time (It) characteristic curve of the all-light-controlled memristor device constructed according to the present invention under green light irradiation;

[0021] Figure 6 The current-time (It) characteristic curve of the all-light-controlled memristor device constructed according to the present invention under alternating irradiation of ultraviolet light and green light is shown. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with specific implementations and with reference to the accompanying drawings.

[0023] Example

[0024] Figure 3 The current-voltage (IV) characteristic curve of the initial state of the all-optically controlled memristor device constructed according to the present invention is shown.

[0025] like Figure 3 As shown, under continuous positive voltage scanning, the device conductance continues to decrease; under continuous negative voltage scanning, the device conductance also continues to decrease.

[0026] Figure 4 The current-time (It) characteristic curve of the all-light-controlled memristor device constructed according to the present invention under ultraviolet light irradiation is shown.

[0027] like Figure 4 As shown in Figure 2, when the device is continuously irradiated with ultraviolet light in the wavelength range of 320-380nm for a long time, the device state current obtained by the 0.1V read voltage gradually increases and gradually reaches a saturation state. This can be explained by (1) under ultraviolet light irradiation, the photoinduced ionization reaction, V O 2+ The increase in the amount of ZnO / MoO x The width of the heterojunction is reduced, resulting in an increase in device conductivity; (2) UV irradiation generates conductive H y MoO x , in MoO x A permeation conduction network is formed in the film, which increases the conductivity of the device and produces an excitation effect.

[0028] Figure 5 The current-time (It) characteristic curve of the all-light-controlled memristor device constructed according to the present invention under green light irradiation is shown.

[0029] like Figure 5 As shown in Figure 2, when the device is continuously irradiated with green light in the wavelength range of 500-560nm for a long time, the device state current obtained by the 0.1V read voltage gradually decreases and gradually reaches a stable state. This can be explained by the fact that under the irradiation of long-wavelength light, the electrons in the potential well formed by the bending of the ZnO energy band through photoexcitation can easily pass through or jump over the potential barrier and enter the MoO x conduction band. Some electrons are O 2+ Capture and then convert to V O , the potential barrier becomes wider, causing the device conductance to decrease, producing an inhibitory effect.

[0030] Figure 6 The current-time (It) characteristic curve of the all-light-controlled memristor device constructed according to the present invention under alternating irradiation of ultraviolet light and green light is shown.

[0031] like Figure 6 As shown, when the device is placed in the initial state, the device is illuminated alternately with ultraviolet light and green light, which can complete the continuous modulation of light excitation and light inhibition and realize full light-controlled modulation.

[0032] In summary, the all-optically controlled memristor device provided by the present invention can be controlled by adjusting the ZnO / MoO x The barrier width of the heterojunction can achieve reversible activation and inhibition of light gating under the regulation of ultraviolet light and green light.

Claims

1. A double-layer thin film structure all-light-controlled memristor device, from bottom to top, is composed of SiO2 substrate, inert electrode, ZnO thin film layer, MoO x Thin film layer, transparent electrode, the ZnO thin film layer and MoO x The thin film layers together constitute the photoelectric memristor layer of the all-optically controlled memristor device; the thickness of the ZnO thin film layer is 100±20nm; the MoO x The thickness of the film layer is 100±30nm.

2. The all-optically controlled memristor device with a double-layer thin film structure according to claim 1, characterized in that: The inert electrode is W or Pt, and the transparent electrode is ITO or FTO.

3. A method for preparing a double-layer thin film structure all-optically controlled memristor device according to claim 1 or 2, characterized in that: The following steps are involved: S1. Ultrasonic clean the SiO2 substrate with acetone, ethanol and deionized water for 8 to 15 minutes in sequence, and blow dry with nitrogen; S2. Deposit a W film on a SiO2 substrate as a bottom electrode. The growth conditions are: sputtering with a tungsten target at a power of 80 W for 5 minutes in a pure argon environment at room temperature; S3, depositing a ZnO film on the W electrode, the growth conditions are: using a zinc oxide target for sputtering at a power of 80 W for 30 minutes in a pure argon environment at room temperature; S4. Deposition of MoO on ZnO film x The film growth conditions are as follows: in a pure argon environment at room temperature, a molybdenum oxide target is sputtered at a power of 80 W for 30 minutes to obtain a photoelectric memristor layer; S5. Depositing a transparent electrode ITO on the photoelectric memristor layer obtained in step S4, the growth conditions are: using an ITO target for sputtering at a power of 30 W for 2 minutes in a pure argon environment at room temperature.

4. The preparation method according to claim 3, characterized in that: In steps S2-S5, the deposition method is magnetron sputtering.

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