Short-wave infrared sensing and storage integrated photoelectric memristor and preparation method thereof

Abstract

According to the short-wave infrared sensing and storage integrated photoelectric memristor and the preparation method thereof, the working wave band of the photoelectric memristor extends from visible light to short-wave infrared, and the short-wave infrared sensing and storage integrated photoelectric memristor is expected to be widely applied to the fields of remote sensing detection, environment monitoring, biomedical imaging, military reconnaissance and the like. The short-wave infrared quantum dot and organic polymer layer and the two gold electrodes are arranged on the substrate, the two gold electrodes are vertically arranged at the two ends of the short-wave infrared quantum dot and organic polymer layer, and an electric field is formed by applying bias voltage to the two gold electrodes; infrared light enters from the top end of the device and is absorbed by the short-wave infrared quantum dots to generate photon-generated carriers, organic high-molecular polymers are doped in the quantum dots, potential barriers are formed due to the fact that energy band differences exist between the quantum dots and organic polymers, Schottky potential barriers exist at the interfaces of the photosensitive layer and the electrodes, migration of the photon-generated carriers is blocked, and therefore the photoelectric conversion efficiency of the device is improved. Carrier recombination is inhibited; and the infrared light stops incidence, the photon-generated carrier continuously crosses the potential barrier, the current is slowly attenuated, and short-wave infrared image memory is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of photoelectric detectors, and in particular to a short-wave infrared sensing and storage integrated photoelectric memristor, and a preparation method of the short-wave infrared sensing and storage integrated photoelectric memristor. Background Art

[0002] The working principle of the photoelectric memristor is based on its unique resistance-changing characteristics. When a light signal is irradiated onto the photoelectric memristor, it causes a change in its internal resistance. This change is related to factors such as the intensity, wavelength, and irradiation time of the light signal, and can be retained for a long time without the influence of external factors. Since the photoelectric memristor has a sensitive response to light signals, it can detect and store light signals of different wavelengths, intensities, and irradiation times. At the same time, the photoelectric memristor has the characteristics of low power consumption and high integration, which makes it possible to build large-scale neural networks and sensor arrays.

[0003] At present, the working range of conventional photoelectric memristors is mainly limited to the visible light to near-infrared band. This limitation limits its application effectiveness in detecting longer wavelength optical signals, especially the short-wave infrared band. Short-wave infrared plays a key role in remote sensing, environmental monitoring, biomedical imaging and military reconnaissance, but conventional memristors have limited response capabilities. In view of this, it is of great strategic significance to study new photoelectric memristors that can respond to the short-wave infrared band. Summary of the invention

[0004] In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to provide a short-wave infrared sensing and storage integrated photoelectric memristor, which extends the working band of the photoelectric memristor from visible light to short-wave infrared, and is expected to be more widely used in remote sensing detection, environmental monitoring, biomedical imaging, military reconnaissance and other fields.

[0005] The technical solution of the present invention is: the short-wave infrared sensing and storage integrated photoelectric memristor comprises: a substrate (1), a short-wave infrared quantum dot and organic polymer layer (2), and a gold electrode (3);

[0006] The short-wave infrared quantum dots, the organic polymer layer and two gold electrodes are on a substrate, and the two gold electrodes are erected at both ends of the short-wave infrared quantum dots and the organic polymer layer, and an electric field is formed by applying a bias voltage to the two gold electrodes;

[0007] Infrared light is incident from the top of the device and is absorbed by short-wave infrared quantum dots to generate photogenerated carriers. By doping organic high molecular polymers inside the quantum dots, a potential barrier is formed due to the energy band difference between the quantum dots and the organic polymers, and there is a Schottky barrier at the interface between the photosensitive layer and the electrode, the migration of photogenerated carriers is blocked, and carrier recombination is suppressed; when the infrared light stops being incident, the photogenerated carriers continue to cross the potential barrier, and the current slowly decays, realizing short-wave infrared image memory.

[0008] A method for preparing a short-wave infrared sensing and storage integrated photoelectric memristor is also provided, which comprises the following steps:

[0009] (1) Synthesizing a short-wavelength mercury telluride quantum dot solution with a wavelength range of 2 to 3 μm by hot injection;

[0010] (2) adding P3HT to the short-wave mercury telluride quantum dot solution and fully dissolving and mixing;

[0011] (3) providing a substrate, and depositing a gold electrode on the substrate by electron beam evaporation technology;

[0012] (4) Depositing a mixed solution of quantum dots and organic matter to the bottom of the precipitate by spin coating, and treating and solidifying the quantum dots with an ethylenedithiol solution.

[0013] The present invention has the following beneficial effects:

[0014] 1. The present invention adopts hot injection to synthesize short-wave quantum dots, and the synthesis scheme is simple, the cost is low, and the output rate is high.

[0015] 2. The photoelectric memristor prepared by the present invention expands the spectral response to short-wave infrared, and is expected to be more widely used in remote sensing, environmental monitoring, biomedical imaging, military reconnaissance and other fields.

[0016] 3. The present invention improves the memory storage capacity of the detector by doping the quantum dot solution with organic high molecular polymer.

[0017] 4. The device preparation method provided by the present invention can be extended to an arrayed focal plane. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the short-wave infrared sensing and storage integrated photoelectric memristor according to the present invention.

[0019] Figure 2 It is a flow chart of a method for preparing a short-wave infrared sensing and storage integrated photoelectric memristor according to the present invention. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0021] It should be noted that the term "comprises" and any variations in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or equipment.

[0022] like Figure 1 As shown, this short-wave infrared sensing and storage integrated photoelectric memristor comprises: a substrate 1, a short-wave infrared quantum dot and organic polymer layer 2, and a gold electrode 3;

[0023] The short-wave infrared quantum dots, the organic polymer layer and two gold electrodes are on a substrate, and the two gold electrodes are erected at both ends of the short-wave infrared quantum dots and the organic polymer layer, and an electric field is formed by applying a bias voltage to the two gold electrodes;

[0024] Infrared light is incident from the top of the device and is absorbed by short-wave infrared quantum dots to generate photogenerated carriers. By doping organic high molecular polymers inside the quantum dots, a potential barrier is formed due to the energy band difference between the quantum dots and the organic polymers, and there is a Schottky barrier at the interface between the photosensitive layer and the electrode, the migration of photogenerated carriers is blocked, and carrier recombination is suppressed; when the infrared light stops being incident, the photogenerated carriers continue to cross the potential barrier, and the current slowly decays, realizing short-wave infrared image memory.

[0025] Preferably, the substrate is made of silicon, sapphire or flexible resin.

[0026] Preferably, the short-wave infrared quantum dots and organic polymer layer are mercury telluride quantum dots and P3HT (poly (3-hexylthiophene-2,5-diyl)) layers, and the thickness is 50 nanometers.

[0027] Preferably, the thickness of the gold electrode is 50 to 100 nanometers.

[0028] like Figure 2 As shown, a method for preparing a short-wave infrared sensing and storage integrated photoelectric memristor is also provided, which comprises the following steps:

[0029] (1) Synthesizing a short-wavelength mercury telluride quantum dot solution with a wavelength range of 2 to 3 μm by hot injection;

[0030] (2) adding P3HT to the short-wave mercury telluride quantum dot solution and fully dissolving and mixing;

[0031] (3) providing a substrate, and depositing a gold electrode on the substrate by electron beam evaporation technology;

[0032] (4) Depositing a mixed solution of quantum dots and organic matter to the bottom of the precipitate by spin coating, and treating and solidifying the quantum dots with an ethylenedithiol solution.

[0033] The present invention has the following beneficial effects:

[0034] 1. The present invention adopts hot injection to synthesize short-wave quantum dots, and the synthesis scheme is simple, the cost is low, and the output rate is high.

[0035] 2. The photoelectric memristor prepared by the present invention expands the spectral response to short-wave infrared, and is expected to be more widely used in remote sensing, environmental monitoring, biomedical imaging, military reconnaissance and other fields.

[0036] 3. The present invention improves the memory storage capacity of the detector by doping the quantum dot solution with organic high molecular polymer.

[0037] 4. The device preparation method provided by the present invention can be extended to an arrayed focal plane.

[0038] Preferably, the step (1) comprises the following sub-steps:

[0039] (1.1) preparing a mercury precursor solution: under an inert gas atmosphere, using oleylamine as a ligand solvent, heating the solvent to 150° C. and maintaining the temperature for 3 hours to completely remove moisture and oxygen in the ligand and the solvent; then, adjusting the system temperature to a stable 110° C., adding mercuric chloride as a mercury source, stirring to fully dissolve and evenly disperse the mercury, and obtaining the desired mercury precursor solution;

[0040] (1.2) preparing a tellurium precursor solution: in an inert gas atmosphere, dispersing tellurium powder as a tellurium source in a trioctylphosphine ligand solvent, heating the solvent to 120° C., and stirring to ensure that the tellurium source is completely dissolved and evenly dispersed in the solvent, thereby preparing a tellurium precursor solution;

[0041] (1.3) Synthesis reaction and post-treatment: Under the continuous protection of inert gas, the tellurium precursor solution is injected into the mercury precursor solution. The temperature of this injection process is controlled at 80°C to 85°C.

[0042] to ensure that the size of the product obtained by the reaction is controlled within 6 to 8 nanometers; after the reaction has been carried out for a period of time, tetrachloroethylene is used as a quencher to terminate the reaction; then, at least one of methanol, ethanol or isopropanol is used as an anti-solvent to centrifuge the reaction system to remove unreacted substances and impurities; after centrifugation, the obtained product is dispersed in a chlorobenzene solvent to obtain a final product dispersion.

[0043] Preferably, the step (2) comprises the following sub-steps:

[0044] (2.1) P3HT was dissolved in chlorobenzene solvent and heated at 60 °C for 12 hours;

[0045] (2.2) Add the P3HT solution prepared in step (2.1) to the mercury telluride quantum dot solution, and oscillate in a mixer to fully mix the solution to obtain a final dispersion of quantum dots and organic matter.

[0046] Preferably, in step (3), a silicon dioxide wafer with a size of 1.5 cm×1.5 cm is selected as the substrate, and the surface is subjected to a standard cleaning process to ensure that the substrate surface is clean and free of impurities. Electron beam evaporation technology is used to evaporate a layer of gold electrode on the surface of the silicon dioxide wafer to ensure that the device has good conductivity.

[0047] Preferably, in the step (4), an appropriate amount of a mixed solution of mercury telluride and P3HT is taken and uniformly deposited on the substrate surface by spin coating at a spin coating speed of 2500 rpm. After spin coating, the quantum dots and the organic layer are treated with ethanedithiol to solidify the quantum dots and optimize the photoelectric performance of the device.

[0048] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. Short-wave infrared sensing and storage integrated photoelectric memristor, characterized by: It comprises: a substrate (1), a short-wave infrared quantum dot and organic polymer layer (2), and a gold electrode (3); The short-wave infrared quantum dots, the organic polymer layer and two gold electrodes are on a substrate, and the two gold electrodes are erected at both ends of the short-wave infrared quantum dots and the organic polymer layer, and an electric field is formed by applying a bias voltage to the two gold electrodes; Infrared light is incident from the top of the device and is absorbed by short-wave infrared quantum dots to generate photogenerated carriers. By doping organic high molecular polymers inside the quantum dots, a potential barrier is formed due to the energy band difference between the quantum dots and the organic polymers, and there is a Schottky barrier at the interface between the photosensitive layer and the electrode, the migration of photogenerated carriers is blocked, and carrier recombination is suppressed; when the infrared light stops being incident, the photogenerated carriers continue to cross the potential barrier, and the current slowly decays, realizing short-wave infrared image memory.

2. The short-wave infrared sensing and storage integrated photoelectric memristor according to claim 1, characterized in that: The substrate is made of silicon, sapphire or flexible resin.

3. The short-wave infrared sensing and storage integrated photoelectric memristor according to claim 2, characterized in that: The short-wave infrared quantum dots and organic polymer layer are mercury telluride quantum dots and P3HT layers, and the thickness is 50 nanometers.

4. The short-wave infrared sensing and storage integrated photoelectric memristor according to claim 3, characterized in that: The thickness of the electro-gold electrode is 50 to 100 nanometers.

5. The method for preparing the short-wave infrared sensing and storage integrated photoelectric memristor according to claim 4, characterized in that: It includes the following steps: (1) Synthesizing a short-wavelength mercury telluride quantum dot solution with a wavelength range of 2 to 3 μm by hot injection; (2) adding P3HT to the short-wave mercury telluride quantum dot solution and fully dissolving and mixing; (3) providing a substrate, and depositing a gold electrode on the substrate by electron beam evaporation technology; (4) Depositing a mixed solution of quantum dots and organic matter to the bottom of the precipitate by spin coating, and treating and solidifying the quantum dots with an ethylenedithiol solution.

6. The method for preparing the short-wave infrared sensing and storage integrated photoelectric memristor according to claim 5, characterized in that: The step (1) comprises the following sub-steps: (1.1) preparing a mercury precursor solution: under an inert gas atmosphere, using oleylamine as a ligand solvent, heating the solvent to 150° C. and maintaining the temperature for 3 hours to completely remove moisture and oxygen in the ligand and the solvent; then, adjusting the system temperature to a stable 110° C., adding mercuric chloride as a mercury source, stirring to fully dissolve and evenly disperse the mercury, and obtaining the desired mercury precursor solution; (1.2) preparing a tellurium precursor solution: in an inert gas atmosphere, dispersing tellurium powder as a tellurium source in a trioctylphosphine ligand solvent, heating the solvent to 120° C., and stirring to ensure that the tellurium source is completely dissolved and evenly dispersed in the solvent, thereby preparing a tellurium precursor solution; (1.3) Synthesis reaction and post-treatment: Under the continuous protection of inert gas, the tellurium precursor solution is injected into the mercury precursor solution. The temperature of the injection process is controlled between 80°C and 85°C to ensure that the size of the product obtained by the reaction is controlled to be 6 to 8 nanometers. After the reaction is carried out for a period of time, tetrachloroethylene is used as a quencher to terminate the reaction. Subsequently, at least one of methanol, ethanol or isopropanol is used as an anti-solvent to centrifuge the reaction system to remove unreacted substances and impurities. After centrifugation, the obtained product was dispersed in chlorobenzene solvent to obtain the final product dispersion.

7. The method for preparing the short-wave infrared sensing and storage integrated photoelectric memristor according to claim 6, characterized in that: The step (2) comprises the following sub-steps: (2.1) P3HT was dissolved in chlorobenzene solvent and heated at 60 °C for 12 hours; (2.2) Add the P3HT solution prepared in step (2.1) to the mercury telluride quantum dot solution, and oscillate in a mixer to fully mix the solution to obtain a final dispersion of quantum dots and organic matter.

8. The method for preparing the short-wave infrared sensing and storage integrated photoelectric memristor according to claim 6, characterized in that: In the step (3), a silicon dioxide wafer with a size of 1.5 cm×1.5 cm is selected as the substrate, and the surface is subjected to a standard cleaning process to ensure that the substrate surface is clean and free of impurities. Electron beam evaporation technology is used to evaporate a layer of gold electrode on the surface of the silicon dioxide wafer to ensure that the device has good conductivity.

9. The method for preparing the short-wave infrared sensing and storage integrated photoelectric memristor according to claim 8, characterized in that: In the step (4), an appropriate amount of a mixed solution of mercury telluride and P3HT is taken and uniformly deposited on the surface of the substrate by spin coating at a spin coating speed of 2500 rpm. After spin coating, ethylenedithiol is used to treat the quantum dots and the organic layer to solidify the quantum dots and optimize the photoelectric performance of the device.

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