An optoelectronic device and its fabrication method, and an artificial vision system.

Abstract

This invention belongs to the field of artificial visual perception neural system technology, specifically relating to an optoelectronic device and its fabrication method, and an artificial vision system. The optoelectronic device provided by this invention includes a transparent backing; and a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer sequentially stacked on the surface of the transparent backing. The photosensitive layer has a chemical composition including one or more of MoS2, graphene, and boron nitride; the resistive switching layer has a chemical composition including Ga2O3 and / or Ta2O5; the bottom electrode layer has a chemical composition including ITO or FTO; and the top electrode layer has a chemical composition including one or more of gold, platinum, aluminum, copper, silver, titanium, and ITO. The optoelectronic device provided by this invention has accurate and stable color recognition capabilities. When applied to an artificial vision system, it can ultimately display accurate recognition results of the external light environment to the user on the terminal, enabling precise color visualization detection and differentiation.

Description

Technical Field

[0001] This invention belongs to the field of artificial visual perception neural system technology, specifically relating to an optoelectronic device and its preparation method, and an artificial visual system. Background Technology

[0002] With the rapid development and application of artificial intelligence and bionic robots, in order to meet increasingly complex functional requirements, the development of devices that can effectively perceive and remember external information, especially color information, has become a research hotspot.

[0003] Among the many human senses, vision is an essential way for the brain to acquire information, accounting for nearly 80% of the information humans receive from the external world. As the basic functional unit of the human brain's neural network, synapses are key to the human visual system. However, artificial synaptic devices cannot directly respond to light stimuli. Artificial visual systems need to be designed using the concept of biological visual transmission pathways, that is, by using additional light-sensing devices to convert light signals into electrical signals that can be matched with artificial synaptic devices.

[0004] Currently, advancements have been made in light-sensing devices such as photodetectors, phototransistors, photoresists, and photoelectric switches, which have been shown to be capable of building artificial vision systems. However, current light-sensing devices have low efficiency in color perception, preventing artificial vision systems from providing users with accurate color visualization, detection, and differentiation on display terminals. Summary of the Invention

[0005] The purpose of this invention is to provide an optoelectronic device and its preparation method, as well as an artificial vision system. The optoelectronic device provided by this invention has the ability to efficiently sense and store different light signals, and the artificial vision system obtained has accurate color recognition function, which can provide users with accurate color visualization detection and differentiation.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides an optoelectronic device, including a transparent backing; and a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer sequentially stacked on the surface of the transparent backing; the photosensitive layer has a chemical composition including one or more of MoS2, graphene, and boron nitride; the resistive switching layer has a chemical composition including Ga2O3 and / or Ta2O5; the bottom electrode layer has a chemical composition including ITO or FTO; and the top electrode layer has a chemical composition including one or more of gold, platinum, aluminum, copper, silver, titanium, and ITO.

[0008] Preferably, the photosensitive layer has a chemical composition of MoS2; the resistive switching layer has a chemical composition of Ga2O3; the bottom electrode layer is ITO; and the top electrode layer is ITO.

[0009] Preferably, the transparent backing is a mica backing.

[0010] Preferably, the thickness of the bottom electrode layer is 200–350 nm; the thickness of the photosensitive layer is 30–50 nm; the thickness of the resistive switching layer is 60–80 nm; and the thickness of the top electrode layer is 80–150 nm.

[0011] This invention provides a method for fabricating the optoelectronic device described in the above technical solution, comprising the following steps:

[0012] According to the chemical composition of the optoelectronic device, a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer are sequentially prepared on the surface of a transparent backing to obtain the optoelectronic device.

[0013] Preferably, the methods for preparing the bottom electrode layer, resistive switching layer, and top electrode layer independently include magnetron sputtering, vacuum thermal evaporation, electron beam evaporation, or pulsed laser deposition; the methods for preparing the photosensitive layer include hydrothermal reaction, mechanical exfoliation, or vapor phase chemical deposition.

[0014] Preferably, the method for preparing the bottom electrode layer, resistive switching layer, and top electrode layer is magnetron sputtering; the bottom electrode layer and top electrode layer are sputtered using DC mode; and the resistive switching layer is sputtered using radio frequency mode.

[0015] The operating parameters for magnetron sputtering fabrication of the bottom electrode layer, resistive switching layer, and top electrode layer include: an independent reference pressure of 3.6 × 10⁻⁶. -3 ~5.4×10 -3 Pa; working pressure independently ranges from 0.6 to 1 Pa; sputtering temperature independently ranges from 15 to 45 °C; gas flow rate independently ranges from 20 to 30 sccm; sputtering energy independently ranges from 50 to 100 W; pre-sputtering time independently ranges from 1 to 3 min; sputtering time independently ranges from 10 to 60 min.

[0016] Preferably, the method for preparing the photosensitive layer is a hydrothermal reaction; the hydrothermal reaction includes the following steps:

[0017] A transparent backing with a bottom electrode layer is immersed in a photosensitive layer precursor solution and subjected to a hydrothermal reaction to form a photosensitive layer on the surface of the bottom electrode layer.

[0018] Preferably, the photosensitive layer precursor solution is a MoS2 precursor solution; the MoS2 precursor solution includes alkali metal molybdate, thioacetamide and water; the mass ratio of the alkali metal molybdate to the thioacetamide is 1:(2-3); the temperature of the hydrothermal reaction is 200-300℃; the holding time of the hydrothermal reaction is 600-660 min.

[0019] This invention provides an artificial vision system, comprising a data acquisition module, an analog-to-digital conversion module, and a processing module connected in sequence. The data acquisition module includes the optoelectronic device described in the above technical solution or the optoelectronic device prepared by the preparation method described in the above technical solution.

[0020] This invention provides an optoelectronic device, comprising a transparent backing; and a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer sequentially stacked on the surface of the transparent backing. The photosensitive layer has a chemical composition including one or more of MoS2, graphene, and boron nitride; the resistive switching layer has a chemical composition including Ga2O3 and / or Ta2O5; the bottom electrode layer has a chemical composition including ITO or FTO; and the top electrode layer has a chemical composition including one or more of gold, platinum, aluminum, copper, silver, titanium, and ITO. The photosensitive layer and resistive switching layer of the optoelectronic device provided by this invention form a heterostructure using the above-mentioned chemical compositions, enabling it to sense and memorize external light signals and identify and distinguish the wavelengths of the acquired light signals. Under both optical and electrical conditions, it achieves artificial synaptic function, thereby realizing accurate and stable color recognition. Therefore, the optoelectronic device provided by this invention simultaneously possesses the functions of photosensing and identifying and distinguishing the wavelengths of light signals. When applied to artificial vision systems, it can display accurate identification results of the external light environment to users, providing precise color visualization detection and differentiation.

[0021] Furthermore, in this invention, the photosensitive layer is chemically composed of MoS2; the resistive switching layer is chemically composed of Ga2O3; the bottom electrode layer is ITO; and the top electrode layer is ITO, resulting in an optoelectronic device with a "mica-ITO / MoS2 / Ga2O3 / ITO" structure. The ITO bottom electrode layer promotes a more complete and uniform distribution of MoS2, reducing defects. The heterostructure formed by MoS2 and Ga2O3 has a more reasonable optical bandgap and strong light absorption coefficient, allowing for more accurate identification and differentiation of optical signal wavelengths. The ITO top electrode layer has high light transmittance and meets flexibility requirements. This results in an optoelectronic device with more precise sensing and identification capabilities for external optical signals.

[0022] Furthermore, in this invention, the transparent backing is a mica backing. The mica backing has flexible light transmission properties, which better simulates the function of the human eye.

[0023] The multi-material structure of the optoelectronic device provided by this invention meets the requirements of flexibility and transparency, providing effective technical support for recognition systems in the field of artificial intelligence simulation. It is expected to play a greater role in realizing a more efficient human visual perception neural system in the future and will promote applications such as bionic eyes and bionic robots.

[0024] This invention provides a method for fabricating the optoelectronic device described in the above technical solution, comprising the following steps: sequentially fabricating a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer on a transparent backing surface to obtain the optoelectronic device. Compared with existing optoelectronic device fabrication methods, the fabrication method provided by this invention is simple and feasible for large-scale fabrication.

[0025] This invention provides an artificial vision system, comprising a data acquisition module, an analog-to-digital conversion module, and a processing module connected in sequence. The data acquisition module includes the optoelectronic device described in the above-described technical solution or the optoelectronic device prepared by the preparation method described in the above-described technical solution. In this invention, in environments with various lighting conditions, the presence of light signals causes the optoelectronic device in this artificial vision system to generate a response current and memorize it. Due to the different response currents caused by different parameters such as light intensity, duration, and wavelength, the difference in response current is converted and acquired by the analog-to-digital conversion (ADC) module, resulting in differentiated and distinguishable digital signals. The processing (MCU) module identifies the digital signals converted by the ADC module and compares them with pre-acquired color recognition template data for one-to-one classification. Finally, the display terminal outputs images of the different colors that have been distinguished and recognized, with a high accuracy rate in color recognition. The artificial vision system provided by this invention offers an effective technical example for recognition systems in the field of artificial intelligence simulation, and is expected to play a greater role in realizing a more efficient human visual perception neural system in the future, and will promote applications such as bionic eyes and bionic robots. Attached Figure Description

[0026] Figure 1 This is a light transmittance diagram of an optoelectronic device with color recognition capability in an embodiment of the present invention;

[0027] Figure 2 This is a flexible transparent physical image of an optoelectronic device with color recognition capability in an embodiment of the present invention;

[0028] Figure 3 This is an electrical test diagram of an optoelectronic device with color recognition capability in an embodiment of the present invention;

[0029] Figure 4 This is an optical test diagram of an optoelectronic device with color recognition capability in an embodiment of the present invention;

[0030] Figure 5 This is a diagram illustrating the "learning-forgetting-relearning" function of an optoelectronic device with color recognition capability under light in an embodiment of the present invention.

[0031] Figure 6 This is a test curve of a photoelectric device with color recognition capability in an embodiment of the present invention under the application of a 1V read voltage multi-band optical signal;

[0032] Figure 7 This is a diagram showing the optoelectronic co-modulation performance of an optoelectronic device with color recognition capability in an embodiment of the present invention.

[0033] Figure 8 This is an illustration and detailed view of the functional areas of an artificial vision system with color recognition capability in an embodiment of the present invention. Detailed Implementation

[0034] This invention provides an optoelectronic device, including a transparent backing; and a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer sequentially stacked on the surface of the transparent backing; the photosensitive layer has a chemical composition including one or more of MoS2, graphene, and boron nitride; the resistive switching layer has a chemical composition including Ga2O3 and / or Ta2O5; the bottom electrode layer has a chemical composition including ITO or FTO; and the top electrode layer has a chemical composition including one or more of gold, platinum, aluminum, copper, silver, titanium, and ITO.

[0035] In this invention, unless otherwise specified, all raw materials / components used in the preparation are commercially available products well known to those skilled in the art.

[0036] The optoelectronic device provided by the present invention includes a transparent backing.

[0037] In this invention, the transparent backing is preferably a mica backing.

[0038] In this invention, the mica backing is flexible and can better simulate the function of the human eye.

[0039] The present invention does not have any special requirements on the thickness of the transparent backing.

[0040] The optoelectronic device provided by the present invention includes a bottom electrode layer disposed on the surface of the transparent backing.

[0041] In this invention, the chemical composition of the bottom electrode layer includes ITO or FTO, preferably ITO.

[0042] In this invention, the ITO bottom electrode layer enables a more uniform and sufficient distribution of the photosensitive layer on the surface, reducing defects.

[0043] In this invention, the thickness of the bottom electrode layer is preferably 200-350 nm, more preferably 300 nm.

[0044] The optoelectronic device provided by the present invention includes a photosensitive layer disposed on the surface of the bottom electrode layer.

[0045] In this invention, the chemical composition of the photosensitive layer includes one or more of MoS2, graphene, and boron nitride, preferably MoS2.

[0046] In this invention, the thickness of the photosensitive layer is preferably 30-50 nm.

[0047] In this invention, the MoS2 has an appropriate optical bandgap and a strong light absorption coefficient, which can effectively improve the light absorption capability of the optoelectronic device.

[0048] The optoelectronic device provided by the present invention includes a resistive switching layer disposed on the surface of the photosensitive layer.

[0049] In this invention, the chemical composition of the resistive switching layer includes Ga2O3 and / or Ta2O5, preferably Ga2O3.

[0050] In this invention, the thickness of the resistive switching layer is preferably 60-80 nm, and more preferably 60 nm or 80 nm.

[0051] In this invention, the photosensitive layer and the resistive switching layer form a heterogeneous structure in the optoelectronic device, which facilitates the simulation of synaptic functions under electrical and optical signals, so as to realize a precise and stable artificial vision system.

[0052] The optoelectronic device provided by the present invention includes a top electrode layer disposed on the surface of the resistive switching layer.

[0053] In this invention, the chemical composition of the top electrode layer includes one or more of gold, platinum, aluminum, copper, silver, titanium and ITO, preferably ITO.

[0054] In this invention, the thickness of the top electrode layer is preferably 80-150 nm, more preferably 150 nm.

[0055] In this invention, the top electrode layer is preferably ITO, which is flexible and transparent. Furthermore, ITO electrodes have extremely high light transmittance, allowing light that would otherwise be absorbed by the photosensitive layer to pass through effectively when used as the top electrode, thereby improving the responsivity of the optoelectronic device.

[0056] The optoelectronic device provided by this invention employs a transparent backing, a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer stacked sequentially, all of which meet the requirements of flexibility and transparency. Simultaneously, the MoS2 layer and the Ga2O3 layer form a heterostructure, facilitating the simulation of synaptic functions under electrical and optical signals, thereby achieving a precise and stable artificial vision system.

[0057] In this invention, the optoelectronic device is preferably used after each layer of the optoelectronic device is deposited as a film or after the optoelectronic device is arranged in an array. In this invention, Figure 8 In this invention, the optoelectronic device is used in an array arrangement. Figure 8 Each electrode in the optoelectronic device array is an optoelectronic device of the present invention.

[0058] This invention provides a method for fabricating the optoelectronic device described in the above technical solution, comprising the following steps:

[0059] According to the chemical composition of the optoelectronic device, a bottom electrode layer, a photosensitive layer, a resistive switching layer, and a top electrode layer are sequentially prepared on the surface of a transparent backing to obtain the optoelectronic device.

[0060] In this invention, the methods for preparing the bottom electrode layer, resistive switching layer and top electrode layer preferably include magnetron sputtering, vacuum thermal evaporation, electron beam evaporation or pulsed laser deposition, and more preferably magnetron sputtering.

[0061] In this invention, the method for preparing the photosensitive layer preferably includes hydrothermal reaction, mechanical exfoliation, or vapor-phase chemical deposition.

[0062] In this invention, when the chemical composition of the photosensitive layer is preferably MoS2, the method for preparing the photosensitive layer is more preferably a hydrothermal reaction.

[0063] In this invention, the bottom electrode layer and the top electrode layer are preferably sputtered in DC mode; the resistive switching layer is preferably sputtered in RF mode.

[0064] In this invention, the preferred operating parameters for magnetron sputtering fabrication of the bottom electrode layer include: a reference pressure preferably of 3.6 × 10⁻⁶. -3 ~5.4×10 -3 Pa; the working pressure is preferably 0.6-1 Pa; the sputtering temperature is preferably 15-45℃; the gas flow rate is preferably 20-30 sccm; the sputtering energy is preferably 50-100 W; the pre-sputtering time is preferably 1-3 min; and the sputtering time is preferably 10-60 min.

[0065] In this invention, the preferred operating parameters for the measurement and control sputtering fabrication of the resistive switching layer include: a reference pressure preferably of 3.6 × 10⁻⁶. -3 ~5.4×10 -3 Pa; the working pressure is preferably 0.6-1 Pa; the sputtering temperature is preferably 15-45℃; the gas flow rate is preferably 20-30 sccm; the sputtering energy is preferably 50-100 W; the pre-sputtering time is preferably 1-3 min; and the sputtering time is preferably 10-60 min.

[0066] In this invention, the preferred operating parameters for the measurement and control sputtering fabrication of the top electrode layer include: a reference pressure preferably of 3.6 × 10⁻⁶. -3 ~5.4×10 -3 Pa; the working pressure is preferably 0.6-1 Pa; the sputtering temperature is preferably 15-45℃; the gas flow rate is preferably 20-30 sccm; the sputtering energy is preferably 50-100 W; the pre-sputtering time is preferably 1-3 min; and the sputtering time is preferably 10-60 min.

[0067] In this invention, the hydrothermal reaction preferably includes the following steps:

[0068] A backing with a bottom electrode layer is immersed in a photosensitive layer precursor solution and subjected to a hydrothermal reaction to form a photosensitive layer on the surface of the bottom electrode layer.

[0069] In this invention, the photosensitive layer precursor solution is preferably a MoS2 precursor solution.

[0070] In this invention, the MoS2 precursor solution preferably comprises alkali metal molybdate, thioacetamide, and water.

[0071] In this invention, the water is preferably deionized water.

[0072] In this invention, the alkali metal molybdate is preferably sodium molybdate.

[0073] In this invention, the mass ratio of the alkali metal molybdate to the thioacetamide is preferably 1:(2-3), more preferably 1:2.

[0074] In this invention, the alkali metal molybdate in the MoS2 precursor solution preferably has a mass concentration of 1 mg / mL.

[0075] In this invention, the preferred method for preparing the MoS2 precursor solution is to dissolve the alkali metal molybdate and thioacetamide in water. Preferably, the dissolution is performed under ultrasonic conditions, and the ultrasonication time is preferably 5–10 minutes. This invention does not have specific requirements regarding the specific implementation process of the ultrasonication.

[0076] In this invention, during the impregnation process, it is preferable to place the backing with the bottom electrode layer at an angle in the photosensitive layer precursor solution.

[0077] In this invention, the hydrothermal reaction is preferably carried out in a reaction vessel.

[0078] In this invention, the temperature of the hydrothermal reaction is preferably 200-300°C, more preferably 200°C.

[0079] In this invention, the holding time for the hydrothermal reaction is preferably 600 to 660 minutes.

[0080] In this invention, after the hydrothermal reaction, the hydrothermal reaction system obtained is preferably cooled naturally to room temperature, and the backing with the photosensitive layer formed after the hydrothermal reaction is then subjected to post-processing. In this invention, the post-processing preferably includes washing with water and drying. In this invention, the washing is preferably done with deionized water, and the number of washing cycles is preferably three. In this invention, the drying is preferably done with nitrogen.

[0081] This invention provides an artificial vision system, comprising a data acquisition module, an analog-to-digital conversion module, and a processing module connected in sequence. The data acquisition module includes the optoelectronic device described in the above technical solution or the optoelectronic device prepared by the preparation method described in the above technical solution.

[0082] In this invention, the response current of the optoelectronic device is preferably 1nA to 1mA.

[0083] In this invention, the artificial vision system preferably further includes a voltage divider module. In this invention, the voltage divider module is located between the acquisition module and the analog-to-digital conversion module, and is connected to both the acquisition module and the analog-to-digital conversion module.

[0084] This invention does not have specific requirements for the resistance value of the voltage divider module; it depends on the initial and response resistance values ​​of the optoelectronic device. In this invention, the resistance value of the voltage divider module is preferably between 10KΩ and 10MΩ to ensure more uniform voltage division by the optoelectronic device, a more significant response voltage effect, and to protect the circuit.

[0085] In this invention, there are no special requirements for the range, resolution, least significant bit, sampling rate, reference level, and number of channels of the ADC converter used in the ADC module; these are determined based on the range of the response voltage of the optoelectronic device. Preferably, the operating parameters of the ADC converter in this invention include: a conversion rate of 10–40 MPSP, a sampling rate of 1 kHz–1 MHz, an input range of 0-5V / 0-20mA, and 4–12 input channels. This ensures more accurate data acquisition while avoiding data redundancy.

[0086] In this invention, there are no special requirements for the model of the MCU processor and peripherals used in the MCU module; the choice depends on the number of colors to be recognized by the optoelectronic devices, the size of the array of optoelectronic devices, and the method of visualizing the recognition results. Preferably, the MCU processor used in this invention should have moderate capabilities and cost-effectiveness.

[0087] In this invention, the artificial vision system preferably further includes a display module. In this invention, the display module is preferably data-connected to the processing module.

[0088] The present invention does not have any special requirements on the type of display module.

[0089] In this invention, the terminal device of the display module preferably includes a computer or a mobile terminal electronic device. This invention does not have special requirements for the mobile terminal electronic device; any mobile terminal electronic device well-known to those skilled in the art can be used, such as a smartwatch, smart bracelet, smartphone, or iPad.

[0090] Compared to existing artificial vision systems, the artificial vision system provided by this invention features a simple optoelectronic device structure with nanoscale dimensions, flexibility, and transparency. The significant differences in the response current of the optoelectronic device under different lighting conditions result in high accuracy in color recognition. This invention integrates the optoelectronic device with peripheral circuitry (analog-to-digital conversion module and processing module), converting the current generated by the device receiving light signals into a visual image that can be used for recognition and monitoring. The artificial vision system provided by this invention offers an effective technology for recognition systems in the field of artificial intelligence simulation, and is expected to play a greater role in realizing a more efficient human visual perception neural system in the future, promoting applications such as bionic eyes and bionic robots.

[0091] The optoelectronic device provided by this invention is a flexible and transparent integrated device similar to the human eye, possessing both the ability to sense and store light signals. This invention integrates the optoelectronic device with its corresponding peripheral circuitry to construct an artificial vision system with color recognition capabilities. Under different lighting conditions, this system has the ability to detect lighting conditions and transmits the data in real time to the processing module for analysis via a data acquisition module. Finally, it provides users with accurate color visualization on the display module.

[0092] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the accompanying drawings and embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0093] Example 1

[0094] ITO bottom electrode layer was fabricated on a mica-backed surface by magnetron sputtering: A 300 nm thick ITO bottom electrode layer was deposited in an argon atmosphere using DC sputtering. The operating parameters for magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 60 W; pre-sputtering time is 1 min; sputtering time is 30 min, to obtain mica-ITO flexible substrate;

[0095] 30 mg of sodium molybdate and 60 mg of thioacetamide were simultaneously dissolved in 30 mL of deionized water at room temperature and sonicated until completely dissolved to obtain a MoS2 precursor solution for later use.

[0096] A cleaned 2cm × 3cm mica-ITO flexible substrate was tilted and placed into a 50mL stainless steel autoclave, and then a MoS2 precursor solution was poured in. The autoclave was then placed in an oven and heated at 200℃ for 10 hours. After natural cooling, the flexible substrate was removed from the autoclave, washed three times with deionized water, and dried with nitrogen gas to obtain a 30nm thick two-dimensional MoS2 thin film (photosensitive layer) on the surface of the ITO bottom electrode layer.

[0097] A Ga2O3 thin film was prepared by magnetron sputtering on a two-dimensional MoS2 thin film layer: A flexible substrate with a photosensitive layer, prepared by hydrothermal method, was placed on the target substrate of a magnetron sputtering apparatus with the two-dimensional MoS2 thin film layer facing upwards. Pre-sputtering was performed first, using a Ga2O3 ceramic target with a purity of 99.99%; the pre-sputtering time was 3 min; and the pre-sputtering power was 80 W. Then, in an argon atmosphere, using the same target as the pre-sputtering, an 80 nm thick Ga2O3 thin film was deposited by magnetron sputtering in radio frequency mode. The operating parameters of the magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 80 W; sputtering time is 40 min.

[0098] A 100 nm thick ITO top electrode layer was deposited on the Ga2O3 thin film surface using DC sputtering in an argon atmosphere. The magnetron sputtering parameters were: reference pressure 4.0 × 10⁻⁶. -3 Pa; working pressure: 1 Pa; sputtering temperature: 25 °C; gas flow rate: 20 sccm; sputtering energy: 60 W; pre-sputtering time: 1 min; sputtering time: 5 min. A color-recognition optoelectronic device with a "mica-ITO / MoS2 / Ga2O3 / ITO" structure was obtained.

[0099] Example 2

[0100] ITO bottom electrode layer was fabricated on a mica-backed surface by magnetron sputtering: A 300 nm thick ITO bottom electrode layer was deposited in an argon atmosphere using DC sputtering. The operating parameters for magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 60 W; pre-sputtering time is 1 min; sputtering time is 30 min, to obtain mica-ITO flexible substrate;

[0101] 30 mg of sodium molybdate and 60 mg of thioacetamide were simultaneously dissolved in 30 mL of deionized water at room temperature and sonicated until completely dissolved to obtain a MoS2 precursor solution for later use.

[0102] A cleaned 2cm × 3cm mica-ITO flexible substrate was tilted and placed into a 50mL stainless steel autoclave, and then a MoS2 precursor solution was poured in. The autoclave was then placed in an oven and heated at 200℃ for 15 hours. After natural cooling, the flexible substrate was removed from the autoclave, washed three times with deionized water, and dried with nitrogen gas to obtain a 40nm thick two-dimensional MoS2 thin film (photosensitive layer) on the surface of the ITO bottom electrode layer.

[0103] A Ga2O3 thin film was prepared by magnetron sputtering on a two-dimensional MoS2 thin film layer: A flexible substrate with a photosensitive layer, prepared by hydrothermal method, was placed on the target substrate of a magnetron sputtering apparatus with the two-dimensional MoS2 thin film layer facing upwards. Pre-sputtering was performed first, using a Ga2O3 ceramic target with a purity of 99.99%; the pre-sputtering time was 3 min; and the pre-sputtering power was 80 W. Then, in an argon atmosphere, using the same target as the pre-sputtering, an 80 nm thick Ga2O3 thin film was deposited by magnetron sputtering in radio frequency mode. The operating parameters of the magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 80 W; sputtering time is 40 min.

[0104] A 100 nm thick ITO top electrode layer was deposited on the Ga2O3 thin film surface using DC sputtering in an argon atmosphere. The magnetron sputtering parameters were: reference pressure 4.0 × 10⁻⁶. -3 Pa; working pressure: 1 Pa; sputtering temperature: 25 °C; gas flow rate: 20 sccm; sputtering energy: 60 W; pre-sputtering time: 1 min; sputtering time: 5 min. A color-recognition optoelectronic device with a "mica-ITO / MoS2 / Ga2O3 / ITO" structure was obtained.

[0105] Example 3

[0106] ITO bottom electrode layer was fabricated on a mica-backed surface by magnetron sputtering: A 300 nm thick ITO bottom electrode layer was deposited in an argon atmosphere using DC sputtering. The operating parameters for magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 60 W; pre-sputtering time is 1 min; sputtering time is 30 min, to obtain mica-ITO flexible substrate;

[0107] 30 mg of sodium molybdate and 60 mg of thioacetamide were simultaneously dissolved in 30 mL of deionized water at room temperature and sonicated until completely dissolved to obtain a MoS2 precursor solution for later use.

[0108] A cleaned 2cm × 3cm mica-ITO flexible substrate was tilted and placed into a 50mL stainless steel autoclave, and then a MoS2 precursor solution was poured in. The autoclave was then placed in an oven and heated at 200℃ for 10 hours. After natural cooling, the flexible substrate was removed from the autoclave, washed three times with deionized water, and dried with nitrogen gas to obtain a 30nm thick two-dimensional MoS2 thin film (photosensitive layer) on the surface of the ITO bottom electrode layer.

[0109] A Ga2O3 thin film was prepared by magnetron sputtering on a two-dimensional MoS2 thin film layer: A flexible substrate with a photosensitive layer, prepared by hydrothermal method, was placed on the target substrate of a magnetron sputtering apparatus with the two-dimensional MoS2 thin film layer facing upwards. Pre-sputtering was performed first, using a Ga2O3 ceramic target with a purity of 99.99%; the pre-sputtering time was 3 min; and the pre-sputtering power was 60 W. Then, a 60 nm thick Ga2O3 thin film was deposited by magnetron sputtering in argon atmosphere using the same target material as the pre-sputtering. The operating parameters of the magnetron sputtering were: reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 80 W; sputtering time is 30 min.

[0110] A 100 nm thick ITO top electrode layer was deposited on the Ga2O3 thin film surface using DC sputtering in an argon atmosphere. The magnetron sputtering parameters were: reference pressure 4.0 × 10⁻⁶. -3 Pa; working pressure: 1 Pa; sputtering temperature: 25 °C; gas flow rate: 20 sccm; sputtering energy: 60 W; pre-sputtering time: 1 min; sputtering time: 5 min. A color-recognition optoelectronic device with a "mica-ITO / MoS2 / Ga2O3 / ITO" structure was obtained.

[0111] Example 4

[0112] ITO bottom electrode layer was fabricated on a mica-backed surface by magnetron sputtering: A 300 nm thick ITO bottom electrode layer was deposited in an argon atmosphere using DC sputtering. The operating parameters for magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 60 W; pre-sputtering time is 1 min; sputtering time is 30 min, to obtain mica-ITO flexible substrate;

[0113] 30 mg of sodium molybdate and 60 mg of thioacetamide were simultaneously dissolved in 30 mL of deionized water at room temperature and sonicated until completely dissolved to obtain a MoS2 precursor solution for later use.

[0114] A cleaned 2cm × 3cm mica-ITO flexible substrate was tilted and placed into a 50mL stainless steel autoclave, and then a MoS2 precursor solution was poured in. The autoclave was then placed in an oven and heated at 200℃ for 15 hours. After natural cooling, the flexible substrate was removed from the autoclave, washed three times with deionized water, and dried with nitrogen gas to obtain a 40nm thick two-dimensional MoS2 thin film (photosensitive layer) on the surface of the ITO bottom electrode layer.

[0115] A Ga2O3 thin film was prepared by magnetron sputtering on a two-dimensional MoS2 thin film layer: A flexible substrate with a photosensitive layer, prepared by hydrothermal method, was placed on the target substrate of a magnetron sputtering apparatus with the two-dimensional MoS2 thin film layer facing upwards. Pre-sputtering was performed first, using a Ga2O3 ceramic target with a purity of 99.99%; the pre-sputtering time was 3 min; and the pre-sputtering power was 60 W. Then, a 60 nm thick Ga2O3 thin film was deposited by magnetron sputtering in argon atmosphere using the same target material as the pre-sputtering. The operating parameters of the magnetron sputtering were: reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 80 W; sputtering time is 30 min.

[0116] A 100 nm thick ITO top electrode layer was deposited on the Ga2O3 thin film surface using DC sputtering in an argon atmosphere. The magnetron sputtering parameters were: reference pressure 4.0 × 10⁻⁶. -3 Pa; working pressure: 1 Pa; sputtering temperature: 25 °C; gas flow rate: 20 sccm; sputtering energy: 60 W; pre-sputtering time: 1 min; sputtering time: 5 min. A color-recognition optoelectronic device with a "mica-ITO / MoS2 / Ga2O3 / ITO" structure was obtained.

[0117] Performance testing

[0118] To verify the characteristics of the color recognition-capable optoelectronic device prepared according to this invention, this invention takes Example 1 as an example and tests the basic optical characteristics, performance, and applications of the prepared optoelectronic device. The test results are as follows: Figures 1-8 As shown.

[0119] Figure 1 The image shows the light transmittance of the optoelectronic device with color recognition capability prepared in Example 1. The high transmittance of mica-ITO, mica-ITO / MoS2, and mica-ITO / MoS2 / Ga2O3 indicates the high transparency of this optoelectronic device.

[0120] Figure 2This is a photograph of the optoelectronic device with color recognition capability prepared in Example 1. The high transparency and flexible characteristics similar to the human eye of the mica-ITO / MoS2 / Ga2O3 can be observed.

[0121] Figure 3 The image shows the electrical test results of the optoelectronic device with color recognition capability prepared in Example 1. The increase in conductance under continuous positive voltage stimulation and the decrease in conductance under continuous negative voltage stimulation demonstrate its synaptic-like electrical properties. Subsequent double-pulse facilitation tests and fitting results with a double exponential function demonstrate its feasibility in simulating an electronic synapse.

[0122] Figure 4 Optical test images of the optoelectronic device with color recognition capability prepared in Example 1 are shown. The increase in conductivity under illumination stimulation of different intensities and durations, and the retention relaxation phenomenon of the current after the illumination is removed, demonstrate its synaptic-like optical performance. The subsequent double-pulse facilitation test and the fitting results with a double exponential function demonstrate its feasibility in simulating a photonic synapse.

[0123] Figure 5 This is a functional diagram of the "learning-forgetting-relearning" process under light for the optoelectronic device with color recognition capability prepared in Example 1. Due to its excellent light absorption and relaxation characteristics, this device can achieve advanced learning and forgetting functions. The response current and relaxation current generated by the optoelectronic device under different illuminations can be collected, and the final processing and differentiation results are visualized.

[0124] Figure 6 This is a test curve of the optoelectronic device with color recognition capability prepared in Example 1 under the application of a mixed photoelectric signal. The device under illumination can be modulated by different voltages. Here, voltages of 1V, 0.5V, 0V, and -0.5V are used to classify the device current into four categories, which correspond to the photocurrent induced by different wavelengths of light. After being collected, the data is finally processed and visualized.

[0125] Figure 7 This image shows the photoelectric co-modulation performance of the optoelectronic device with color recognition capability prepared in Example 1. Masks with different cutout shapes simulate different shapes observed by the human eye. After the light signal passes through the cutouts, a current response region is formed on the array, representing the shape of the object as observed by the human eye. When the wavelength of the irradiated light signal changes, the response current in the array also varies. This current is collected by the acquisition module and processed by the processing module, ultimately displaying patterns of different colors and shapes of the light signal on the display module.

[0126] Figure 8This diagram illustrates and shows a detailed view of the functional areas of the artificial vision system with color recognition capability prepared in Example 1. An array of optoelectronic devices simulates the retina in the human eye, which receives different light signals. Integrated with an ADC module, an MCU module, and a display module, it ultimately constitutes an artificial vision system with color recognition capability. When light signals with different wavelengths and shape parameters illuminate the array of optoelectronic devices, only the illuminated devices generate corresponding response currents. These response currents then flow through the ADC module connected to the device, where they are converted into easily distinguishable and processed digital signals via analog-to-digital conversion. Data from all devices in the array is aggregated in the MCU module, compared with predefined parameters, and finally classified and integrated. The recognition results are then displayed on the display module, completing the color recognition task.

[0127] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. An artificial vision system, comprising a data acquisition module, an analog-to-digital conversion module, and a processing module connected in sequence, characterized in that, The acquisition module is an optoelectronic device; The method for fabricating the optoelectronic device is as follows: ITO bottom electrode layer was fabricated on a mica-backed surface by magnetron sputtering: A 300 nm thick ITO bottom electrode layer was deposited in an argon atmosphere using DC sputtering. The magnetron sputtering parameters were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 60 W; pre-sputtering time is 1 min; sputtering time is 30 min, to obtain mica-ITO flexible substrate; At room temperature, 30 mg of sodium molybdate and 60 mg of thioacetamide were simultaneously dissolved in 30 mL of deionized water and sonicated until completely dissolved to obtain a MoS2 precursor solution for later use. A cleaned 2cm×3cm mica-ITO flexible substrate was tilted and placed into a 50mL stainless steel autoclave. Then, a MoS2 precursor solution was poured in. The autoclave was then placed in an oven and heated at 200℃ for 10 hours. After natural cooling, the flexible substrate was removed from the autoclave, washed three times with deionized water, and dried with nitrogen gas to obtain a 30nm thick two-dimensional MoS2 thin film on the surface of the ITO bottom electrode layer. A Ga2O3 thin film was prepared by magnetron sputtering on a two-dimensional MoS2 thin film layer: A flexible substrate with a photosensitive layer, prepared by hydrothermal method, was placed on the target substrate of a magnetron sputtering apparatus with the two-dimensional MoS2 thin film layer facing upwards. Pre-sputtering was performed first, using a Ga2O3 ceramic target with a purity of 99.99%; the pre-sputtering time was 3 min; and the pre-sputtering power was 80 W. Then, in an argon atmosphere, using the same target as the pre-sputtering, an 80 nm thick Ga2O3 thin film was deposited by magnetron sputtering in RF mode. The operating parameters of the magnetron sputtering were: a reference pressure of 3.6 × 10⁻⁶. -3 Pa; working pressure: 1 Pa; sputtering temperature: 25 °C; gas flow rate: 20 sccm; sputtering energy: 80 W; sputtering time: 40 min; A 100 nm thick ITO top electrode layer was deposited on the Ga2O3 thin film surface using DC sputtering in an argon atmosphere. The magnetron sputtering parameters were: a reference pressure of 4.0 × 10⁻⁶. -3 Pa; working pressure is 1 Pa; sputtering temperature is 25℃; gas flow rate is 20 sccm; sputtering energy is 60 W; pre-sputtering time is 1 min; sputtering time is 5 min.

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