Stretchable wide-band light-adaptive-synaptic transistor based on quasi-continuous hybrid photosensitive layer and its preparation method

Abstract

The present invention discloses a stretchable wide-band light-adaptive synaptic transistor based on a quasi-continuous hybrid photosensitive layer and a preparation method thereof. The transistor is constructed by a fully stretchable transistor with a bottom-gate top-contact structure and a stretchable quantum dot / elastomer hybrid photosensitive layer. The stretchable quantum dot / elastomer hybrid photosensitive layer is prepared by regulating the blending ratio, pre-aggregation morphology and self-assembled quasi-continuous microsphere morphology of photosensitive quantum dots and elastomer polymers. The intrinsic stretchable wide-band light-adaptive synaptic transistor prepared by the present invention has excellent field effect characteristics, outstanding photoelectric response performance and high tensile strain capacity; at the same time, it has excellent synaptic behavior simulation function, wide-band bionic visual adaptive function and imaging effect, broadening the application prospects of quantum dots in the construction of stretchable devices, and providing a practical strategy for future wearable optoelectronic devices, electronic skin, brain-like neural computing and bionic visual networks.

Description

Technical Field

[0001] The present invention belongs to the technical field of wearable and skin-like optoelectronic devices, and specifically relates to a method for regulating the self-assembly of photosensitive quantum dot / elastomer hybrid photosensitive films. It mainly involves the preparation of a hybrid photosensitive layer with a quasi-continuous-microsphere morphology, and a stretchable wide-band photosynaptic transistor constructed based on the quasi-continuous hybrid photosensitive layer and its preparation method, ultimately achieving excellent photosynaptic imaging. Background Art

[0002] Stretchable optoelectronic devices are a major research area in the development of smart wearable electronics, showing remarkable potential in areas such as electronic skin, medical monitoring, and human-computer interaction. Stretchable optoelectronic devices possess high conformability, flexibility, and optoelectronic stability, enabling precise sensing, conversion, and display of optoelectronic signals under highly flexed conditions ((a) Y.S. Bian, K. Liu, Y. Ran, et al. Nat. Commun 2022, 13, 7163. (b) K. Liu, Y.S. Bian, J.H. Kuang, Adv. Mater. 2022, 34, 2107. (c) Lee, Y., Liu, Y., Seo, D.G. et al. Nat. Biomed. Eng., 2023, 7, 511–519.). The development of smart wearable electronics urgently requires the development of high-efficiency, low-power, and multifunctional systems, particularly flexible electronic devices that integrate sensing, computing, and storage. Stretchable phototransistors offer fast response, high bandwidth, and low crosstalk, demonstrating significant advantages in developing simulative visual neural systems, including synaptic plasticity, biomimetic visual adaptation, and neural network learning. However, achieving intrinsically stretchable and adaptive phototransistors with synaptic integration still faces numerous challenges, including the development of stretchable photosensitive materials and the fabrication and integration of stretchable phototransistors (CJ Wang, YH Liu, P. Feng, et al. Advanced Materials. 2016, 28, 5878-5885).

[0003] Stretchable photosensitive materials are key to the development of stretchable optoelectronic devices. Currently reported high-performance photosensitive layers primarily rely on inorganic materials such as perovskites, molybdenum disulfide, and lead sulfide. These materials often suffer from high brittleness, low stability, rough interfaces, and complex preparation processes, making flexible integration difficult. Organic optoelectronic materials offer unique advantages such as intrinsic flexibility, biocompatibility, and tunable molecular structures. However, their limited photoresponse and wavelength ranges hinder their further development and application ((a) ZH He, HG Shen, DKY e, et al. Nature Electronics. 2021, 4, 522-529. (b) Liao, F., Zhou, Z., Kim, BJ, et al. Nature Electronics. 2022, 5, 84–91. (c) MY Zhang, ZG Chi, GQ Wang, et al. Advanced Materials. 2022, 2205679). Therefore, developing stretchable photosensitive materials with wide response, high stability, and durability is an important prerequisite for constructing intrinsically stretchable optoelectronic devices. Furthermore, achieving multifunctional integrated stretchable light-adaptive devices still faces numerous challenges, particularly maintaining stable interfaces and performance between functional layers under high deformation. Therefore, designing effective interface control methods and functional integration technologies is crucial for further expanding the application of functionalized electronic skin in neuromorphic computing and imaging. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in existing research, one object of the present invention is to prepare a quantum dot / elastomer hybrid photosensitive film with a quasi-continuous-microspherical morphology having intrinsic stretchability, high photosensitivity and easy integration properties by regulating the pre-aggregation morphology of photosensitive quantum dots and elastomeric polymers and the self-assembly morphology of hybrid films.

[0005] Another object of the present invention is to provide a stretchable broadband light-adaptive-synaptic transistor based on a morphology-controllable stretchable quasi-continuous quantum dot / elastomer hybrid photosensitive layer and a preparation method thereof. The transistor has a high mobility (>0.2cm 2 V -1 s -1 ), high light-to-dark current ratio (>10 5 ), high tensile strain (>100%), excellent synaptic behavior simulation (paired pulse facilitation PPF>270%, short-range plasticity STM, long-range plasticity LTM), broad-band (ultraviolet light, visible light and near-infrared light) bionic visual adaptive function (light intensity and gate voltage dependent light and dark adaptation) and imaging effect.

[0006] The stretchable broadband light-adaptive-synaptic transistor provided by the present invention has a bottom-gate top-contact structure, which comprises, from bottom to top, a stretchable substrate, a stretchable gate electrode, a stretchable hybrid dielectric layer, a stretchable hybrid polymer semiconductor layer, a stretchable source electrode and a stretchable drain electrode in the same plane, and a stretchable quantum dot / elastomer hybrid photosensitive layer, wherein the stretchable quantum dot / elastomer hybrid photosensitive layer covers the stretchable source and drain electrodes;

[0007] The light adaptation range of the stretchable wide-band light-adaptive-synaptic transistor includes ultraviolet light, visible light, and near-infrared light.

[0008] The stretchable gate electrode, the stretchable source electrode and the stretchable drain electrode of the stretchable broadband light-adaptive-synaptic transistor are all made of carbon nanotube material or silver nanowire material;

[0009] The carbon nanotube material is a single-walled carbon nanotube, including any one of the models P2-SWNT, P3-SWNT, P5-SWNT, P8-SWNT and P9-SWNT;

[0010] The silver nanowire material is any one of GS-SNW-20, GS-SNW-25, GS-SNW-30 and GS-SNW-40.

[0011] The stretchable hybrid dielectric layer in the stretchable broadband light-adaptive-synaptic transistor is made by blending an elastomer and carbon quantum dots;

[0012] The elastomeric polymer is selected from any one of polydimethylsiloxane (PDMS), hydrogenated styrene-butadiene block copolymer (SEBS), polyurethane elastomer (PU), styrene-butadiene rubber (SBS) and natural rubber (NR);

[0013] The carbon quantum dots have the characteristics of being uncharged, having high dielectric constant and narrow particle size, with a size of 1-5 nm;

[0014] The mixing mass ratio of the elastomeric polymer and the carbon quantum dots is 100:0.5 to 100:10, preferably 100:1.5 to 100:5, specifically 100:3.5, 100:5;

[0015] The thickness of the stretchable hybrid dielectric layer may be 1300-2500 nm, preferably 1600-1900 nm.

[0016] The stretchable hybrid polymer semiconductor layer of the stretchable broadband light-adaptive-synaptic transistor is prepared from a stretchable hybrid polymer blend system of an elastomeric polymer and a conjugated polymer;

[0017] The elastomeric polymer is the same as the elastomeric polymer used in the stretchable hybrid dielectric layer;

[0018] The conjugated polymer is any one of poly(2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)diketopyrrole[3,4-c]pyrrole-1,4-dione-alt-thiophene[3,2-b]thiophene) (DPPT-TT), poly(2,5-bis(3-alkylthiophen-2-yl)thiophene[3,2-b]thiophene) (PBTTT), poly(quaterthiopheneacetic acid diketopyrrole) (PTDPPTFT4), polyisoindigodithiophene (PII2T) and poly(3-hexylthiophene) (P3HT);

[0019] The mass ratio of the conjugated polymer to the elastomeric polymer is 1:9 to 9:1, preferably 3:7 to 5:5;

[0020] The thickness of the stretchable hybrid polymer semiconductor layer is 30-100 nm, preferably 50-70 nm.

[0021] The stretchable quantum dot / elastomer hybrid photosensitive layer of the stretchable broadband light-adaptive-synaptic transistor is prepared by regulating the blending ratio of photosensitive quantum dots and elastomer polymer, pre-aggregation morphology, and self-assembled quasi-continuous-microsphere morphology;

[0022] The photosensitive quantum dots are any one of cesium lead chloride quantum dots (CsPbCl3), cesium lead bromine quantum dots (CsPbBr3), cesium lead iodine quantum dots (CsPbI3), cesium lead iodine quantum dots (CsPbI3), cadmium telluride (CdTe), cadmium sulfide (CdS) and lead sulfide (PbS);

[0023] The photosensitive quantum dots have the characteristics of high quantum yield and a size of 1 to 10 nm;

[0024] The elastomeric polymer is the same as the elastomeric polymer used in the stretchable hybrid dielectric layer and the stretchable hybrid polymer semiconductor layer;

[0025] The blending mass ratio of the photosensitive quantum dots and the elastomeric polymer is 10:0.5 to 10:3, preferably 10:1;

[0026] The thickness of the stretchable quantum dot / elastomer hybrid photosensitive layer film is 10-50 nm;

[0027] The self-assembled quasi-continuous-microsphere morphology is achieved by regulating the surface energy of the substrate;

[0028] The surface energy of the substrate is achieved through vacuum oxygen plasma treatment, and the surface energy control range is 10-65 millijoules per square centimeter.

[0029] In the stretchable broadband optically adaptive-synaptic transistor, the stretchable substrate is prepared from any one of the elastomeric polymers used in the stretchable hybrid dielectric layer;

[0030] The thickness of the stretchable substrate is 100 μm to 2 mm, preferably 0.6-1 mm.

[0031] The method for preparing the stretchable broadband optically adaptive synaptic transistor provided by the present invention comprises the following steps:

[0032] (1) preparing the stretchable substrate, the stretchable gate electrode, the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer, the stretchable source electrode and the stretchable drain electrode on the substrate with the self-assembled molecular layer respectively;

[0033] (2) preparing the stretchable quantum dot / elastomer hybrid photosensitive layer on a polydimethylsiloxane (PDMS) elastomer film substrate that has been surface-treated by vacuum oxygen plasma;

[0034] (3) Using tweezers, the stretchable substrate is transferred from the substrate with the self-assembled molecular layer, and then the stretchable substrate is gently covered on the stretchable gate electrode from one side; the stretchable gate electrode is transferred to the stretchable substrate by a thermal bonding-transfer method; then, the same method and steps are used to sequentially transfer the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer, the stretchable source electrode and the stretchable drain electrode located on the same plane, and the stretchable quantum dot / elastomer hybrid photosensitive layer from the self-assembled monolayer substrate or the substrate with an elastomer film to the stretchable gate electrode, thereby obtaining a stretchable wide-band light-adaptive-synaptic transistor based on a morphology-controllable quasi-continuous quantum dot / elastomer hybrid photosensitive layer.

[0035] In the above preparation steps, the substrate is selected from any one of silicon wafer, glass, ceramic and quartz;

[0036] The substrate is cleaned by ultrasonic cleaning with detergent, deionized water, acetone, and ethanol in sequence, blown dry with a nitrogen gun, and then subjected to vacuum oxygen plasma treatment to obtain a clean substrate;

[0037] The ultrasonic cleaning conditions are as follows: ultrasonic power of 10-100 watts, ultrasonic time of 1-30 minutes, and ultrasonic frequency of 10-100 kHz;

[0038] The vacuum oxygen plasma treatment conditions are: the treatment time is 1-30 minutes.

[0039] The substrate with the self-assembled molecular layer is prepared by heating the clean substrate with any one of octadecyltrimethoxysilane, octadecyltrichlorosilane, octadecyltrichlorosilane and phenyltrichlorosilane under vacuum conditions or immersing the substrate in a solution;

[0040] The conditions for the heating treatment under vacuum conditions are: vacuum degree of 0.1 Pascal, heating temperature of 50-150° C., and heating time of 1-5 hours;

[0041] The conditions for the immersion treatment in the solution are: using any one of n-hexane, n-heptane, isohexane and cyclohexane as a solvent; the volume ratio of the octadecyltrimethoxysilane, octadecyltrichlorosilane, octadecyltrichlorosilane or phenyltrichlorosilane to the n-hexane, n-heptane, isohexane or cyclohexane is 1:200-1:1000, and the immersion time is 0.1 to 3 hours.

[0042] In the above preparation steps, the polydimethylsiloxane (PDMS) elastomer film substrate is prepared by cross-linking and diluting a polydimethylsiloxane (PDMS) stock solution, a cross-linking agent, and a solvent in a certain proportion, and then depositing the resultant solution onto the clean substrate;

[0043] The mass ratio of the polydimethylsiloxane (PDMS) stock solution to the cross-linking agent is 10:1 to 20:1, preferably 10:1;

[0044] The mass ratio of the mixed solution of the polydimethylsiloxane (PDMS) stock solution and the cross-linking agent to the solvent is 1:5 to 1:10, preferably 1:5;

[0045] The solvent is any one of cyclohexane, n-hexane, isohexane, and toluene, preferably cyclohexane;

[0046] The cross-linking agent is a commercial PDMS supporting cross-linking agent purchased, the trade name is SYLGARD TM 184 SiliconeElastomer or SYLGARD TM 186 Silicone Elastomer (including prepolymer solution and cross-linking agent); manufacturer: Dow Chemical Company; model: Sylgard-184 or Sylgard-186.

[0047] The thickness of the polydimethylsiloxane (PDMS) elastomer film substrate is 500 to 3000 nm, preferably 1000 nm;

[0048] The vacuum oxygen plasma treatment has a vacuum degree of 0.3 to 0.8 Pascal, a power of 10 to 30 watts, and a treatment time of 0.5 to 10 minutes.

[0049] In the above preparation steps, the stretchable substrate, the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer, the stretchable quantum dot / elastomer hybrid photosensitive layer and the elastomer film substrate are all prepared by solution deposition;

[0050] The solution deposition method is any one of drop coating, spin coating, blade coating, roll coating, brush coating and film drawing;

[0051] The solvent used in the solution deposition method is any one of toluene, xylene, chlorobenzene, dichlorobenzene, methane, chloroform, dichloromethane, n-hexane or cyclohexane;

[0052] The solution concentration of the stretchable substrate is 100-300 mg / mL;

[0053] The solution concentration of the stretchable hybrid dielectric layer is 50-100 mg / mL;

[0054] The solution concentration of the stretchable hybrid polymer semiconductor layer is 5-15 mg / mL.

[0055] In the above preparation steps, the stretchable gate electrode, the stretchable source electrode and the stretchable drain electrode are all prepared by a spraying method;

[0056] The solvent used is any one of water, ethanol, isopropanol or a mixed solvent thereof;

[0057] The spraying conditions are as follows: the temperature of the substrate is 60-120° C., the distance between the spray gun nozzle and the substrate is 5-12 cm, the spraying rate is 0.3-3 mL / min, and the spraying volume is 1-3 mL.

[0058] In order to ensure high resolution of the stretchable gate electrode, the stretchable source electrode and the stretchable drain electrode, the substrate with the self-assembled molecular layer is placed between a strong magnet and a patterned nickel or iron mask;

[0059] In the above preparation steps, the thermal bonding process is carried out in a vacuum drying oven;

[0060] The heat bonding conditions are as follows: a vacuum degree of 0.1 to 3 Pascals, a heat treatment temperature of 30 to 80° C., and a heat treatment time of 0.1 to 1 hour.

[0061] The beneficial effects of the present invention are as follows: the present invention controls the pre-aggregation morphology of photosensitive quantum dots and elastomeric polymers, and modifies the surface energy of the substrate film to achieve the control of the quasi-continuous morphology of the quantum dot / elastomer hybrid photosensitive layer film, thereby preparing a quantum dot / elastomer hybrid photosensitive film with a quasi-continuous-microspherical morphology having intrinsic stretchability, high photosensitivity and easy integration characteristics, and obtaining an intrinsically stretchable wide-band light-adaptive-synaptic transistor based on the quasi-continuous quantum dot / elastomer hybrid photosensitive layer. The intrinsically stretchable wide-band light-adaptive-synaptic transistor prepared by the present invention has excellent field-effect characteristics, outstanding photoelectric response performance and high tensile strain capacity; at the same time, it has outstanding synaptic behavior simulation functions (double-pulse facilitation PPF, short-range plasticity STM, long-range plasticity LTM), wide-band (ultraviolet light, visible light and near-infrared light) bionic visual adaptive functions (light intensity and gate voltage-dependent light and dark adaptation) and imaging effects, which broadens the application prospects of quantum dots in the construction of stretchable devices and provides a practical strategy for future wearable optoelectronic devices, electronic skin, brain-like neural computing and bionic visual networks. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is a schematic structural diagram of the intrinsically stretchable wide-band light-adaptive-synaptic transistor based on the morphology-controllable quasi-continuous quantum dot / elastomer hybrid photosensitive layer of the present invention.

[0063] Figure 2 The atomic force microscope images of the quasi-continuous quantum dot / elastomer hybrid photosensitive layer with controllable morphologies prepared in Example 1 and Comparative Example 2 of the present invention are shown. Figure 2 Figure a is an atomic force microscope image of Example 1; Figure 2 Middle b is the atomic force microscope image of comparative example 2.

[0064] Figure 3 The characteristic transfer curves of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 and Comparative Example 1 of the present invention under different 365nm light intensities are shown. Figure 3 a is the characteristic transfer curve of Example 1; Figure 3 The left axis of b is the characteristic transfer curve of comparative example 1; the left axes of a and b are the relationship between |source-drain current| and gate voltage.

[0065] Figure 4 This is a comparison curve of single light pulse time and current of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 of the present invention and Comparative Example 1.

[0066] Figure 5 In the figure a, the visual bionic adaptive characteristics of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 of the present invention. Figure 5 Middle b and Figure 5 c is the relationship between the on-state current and the light-to-dark current ratio of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 of the present invention and the tensile strain; Figure 5 b is the relationship between the on-state current and the light-to-dark current ratio of the stretchable broadband light-adaptive-synaptic transistor prepared in Example 1 of the present invention and the number of stretching cycles; Figure 5 In the figure c, the relationship between the bionic visual adaptive function of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 of the present invention and the tensile strain.

[0067] Figure 6 This is a diagram of the visual bionic adaptive characteristics of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 of the present invention under different gate voltages and different stretching states.

[0068] Figure 7 These are adaptive imaging images of the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 of the present invention at different time intervals under 365nm light. DETAILED DESCRIPTION

[0069] The present invention will be further described in detail below in conjunction with specific embodiments. The examples provided are only for illustrating the present invention and are not intended to limit the scope of the present invention. The examples provided below can serve as a guide for further improvements by those skilled in the art and are not intended to limit the present invention in any way.

[0070] Unless otherwise specified, the experimental methods in the following examples are conventional methods and were performed according to the techniques or conditions described in the literature in the field or according to the product instructions. The materials and reagents used in the following examples, unless otherwise specified, were all commercially available.

[0071] In the present invention, the optical and electrical properties of the intrinsically stretchable broadband light-adaptive-synaptic transistor are measured under atmospheric and room temperature conditions.

[0072] The carbon quantum dots used in the following examples were purchased from Suzhou Guona High-Tech Co., Ltd.

[0073] Cesium lead bromine quantum dots were purchased from Nanjing 2D Nanotechnology Co., Ltd., with the trade name of 513 nm perovskite quantum dots and model number CsPbBr3.

[0074] The polydimethylsiloxane stock solution and cross-linking agent used were SYLGARD μ184 Silicone Elastomer.

[0075] Example 1

[0076] In this example, an intrinsically stretchable broadband light-adaptive synaptic transistor based on a quasi-continuous-microspherical quantum dot / elastomer hybrid photosensitive layer was prepared according to the following steps:

[0077] 1) Using a silicon wafer as a substrate, ultrasonic treatment was performed sequentially with detergent, deionized water, acetone, and ethanol at a power of 40 W and a frequency of 30 kHz for 10 minutes. After being blown dry with a nitrogen gun, the cleaned silicon wafer was subjected to vacuum oxygen plasma treatment (power of 60 Hz) for 5 minutes. The clean silicon wafer and 1 μL of octadecyltrimethoxysilane were then placed in a culture dish. The culture dish was placed in a vacuum drying oven at a vacuum degree of 0.1 Pa and 120°C for 3 hours. After the vacuum drying oven cooled to room temperature, the culture dish was removed to obtain a silicon wafer with a self-assembled molecular layer.

[0078] 2) Place the silicon wafer with the self-assembled molecular layer on a hot plate, slowly draw out 0.5 ml of SEBS toluene solution (concentration of 150 mg / mL) with a 1 mL syringe and evenly drop-coat it on the silicon wafer with the self-assembled molecular layer. Then, keep it at 40°C for 2 hours and then at 90°C for 1 hour to obtain a stretchable substrate with a thickness of 1 mm.

[0079] 3) Place the silicon wafer with a self-assembled molecular layer prepared in step 1) on a magnet, and then place a patterned nickel mask plate on the silicon wafer, so that the mask plate is tightly attached to the silicon wafer with a self-assembled molecular layer. Gently place the magnet, silicon wafer and mask plate on a hot plate at 60°C for 5 minutes, use a 2mL pipette to transfer 1.5mL of carbon nanotube P3-SWNT isopropanol solution (0.2mg / mL) to the volume chamber of the spray gun, and then evenly spray it on the silicon wafer with a self-assembled molecular layer at a rate of 0.15mL / min (wherein the distance between the spray gun nozzle and the silicon wafer is 8cm), to obtain a patterned stretchable gate electrode.

[0080] 4) Place the silicon wafer with the self-assembled molecular layer prepared in step 1) at the center of the rotor of a spin coater. Use a 1 mL pipette to draw 200 μL of a mixed solution of SEBS and carbon quantum dots (toluene solvent, SEBS:CQD mass ratio of 100:3.5, mixed solution concentration of 100 mg / mL) and evenly drop it onto the silicon wafer with the self-assembled molecular layer. Start the spin coater and maintain the speed at 1000 rad / min for 1 minute. Finally, remove the silicon wafer and anneal it on an 80°C hot plate for 30 minutes to obtain a stretchable hybrid dielectric layer with a thickness of 1800 nm.

[0081] 5) The silicon wafer with the self-assembled molecular layer prepared in step 1) was placed at the center of the rotor of a spin coater. A 30 μL solution of poly(2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)dionepyrrolo[3,4-c]pyrrole-1,4-dione-3-thieno[3,2-b]thiophene) / hydrogenated styrene-butadiene block copolymer in chlorobenzene (wherein the mass ratio of the two polymers was 5:5 and the mixture solution concentration was 10 mg / mL) was evenly dropped onto the silicon wafer. The spin coater was started and maintained at a speed of 3000 rad / min for 1 minute. Finally, the silicon wafer was removed and placed on a hot plate at 150°C for 20 minutes to obtain a stretchable hybrid polymer semiconductor layer with a thickness of 50 nm.

[0082] 6) The silicon wafer with the self-assembled molecular layer prepared in step 1) is placed on a magnet, and then the patterned nickel mask is placed on the silicon wafer, so that the mask is tightly attached to the silicon wafer with the self-assembled molecular layer. The magnet, silicon wafer and mask are gently placed on a hot plate at 110°C for 15 minutes, and then 1.5 mL of an isopropanol solution of carbon nanotubes P3-SWNT (concentration 0.15 mg / mL) is extracted with a 2 mL pipette, and then evenly sprayed on the silicon wafer with the self-assembled molecular layer at a rate of 0.1 mL / min (wherein the distance between the spray gun nozzle and the silicon wafer is 9 cm), to obtain a patterned stretchable source electrode and a stretchable drain electrode (channel length and channel width are 200 μm and 4000 μm, respectively).

[0083] 7) Weigh the polydimethylsiloxane stock solution and the crosslinker in a 10:1 mass ratio to create a mixed solution. Then, dilute the mixture to the cyclohexane solution in a 1:5 mass ratio. Place a silicon wafer as the substrate at the center of the spin coater rotor. Use a 50μL pipette to draw 30μL of the resulting mixed elastomer solution and evenly drop it onto the wafer. Start the spin coater at a speed of 6000 rad / min for 1 minute. Finally, remove the wafer and place it on a hot plate at 120°C for 20 minutes to obtain the elastomer film substrate.

[0084] 8) Place the elastomer film substrate prepared in step 7) in a vacuum oxygen plasma treatment apparatus, set the vacuum degree to 0.5 Pascal, the power to 50 watts, and perform vacuum oxygen plasma treatment for 6 minutes to obtain a surface-activated elastomer film substrate (surface energy of 40.49 millijoules per square centimeter). Then, place the substrate at the center of the rotor of the coating machine, use a 50μL pipette to extract 30μL of a hexane solution of cesium lead bromide quantum dots / hydrogenated styrene-butadiene block copolymer (wherein the mass ratio of quantum dots to copolymer is 10:1 and the mixture solution concentration is 10mg / mL), and evenly drop it on the substrate. Start the coating machine and maintain it at a speed of 2000rad / min for 1 minute. Finally, remove the substrate and place it on a hot plate at 50°C for 5 minutes to obtain a stretchable quantum dot / elastomer hybrid photosensitive layer with a quasi-continuous-microspherical morphology.

[0085] 9) Use pointed tweezers to gently peel off the stretchable substrate from the substrate with the self-assembled molecular layer, then gently cover the stretchable substrate from one side on the stretchable gate electrode, and place it in a vacuum drying oven with a vacuum degree of 0.1 Pascal at 60°C for 20 minutes. After the temperature drops to room temperature, use pointed tweezers to gently transfer the stretchable substrate. Through this process, the stretchable gate electrode can be transferred to the stretchable substrate. Then, using the same method and steps, the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer, the stretchable source electrode and the stretchable drain electrode located in the same plane, and the stretchable quasi-continuous-microspherical morphology quantum dot / elastomer hybrid photosensitive layer are transferred to the stretchable gate electrode in turn, and an intrinsic stretchable wide-band light-adaptive-synaptic transistor based on the quasi-continuous-microspherical morphology quantum dot / elastomer hybrid photosensitive layer can be obtained, and the structure is as follows: Figure 1 shown.

[0086] Comparative Example 1

[0087] According to the same preparation method as Example 1, only the mixed solution of cesium lead bromide (CsPbBr3) quantum dots and SEBS in step 8) (the solvent is n-hexane, the mass ratio of CsPbBr3 quantum dots and SEBS is 10:1, and the concentration of the mixed solution is 10 mg / mL) is replaced with a cesium lead bromide (CsPbBr3) quantum dot solution (the solvent is n-hexane, and the solution concentration is 10 mg / mL). The thickness of the perovskite quantum dot photosensitive layer prepared in Comparative Example 1 is consistent with the thickness of the intrinsic stretchable quasi-continuous-microsphere quantum dot / elastomer hybrid photosensitive layer prepared in Example 1, which is about 20 nm.

[0088] Comparative Example 2

[0089] The same preparation method as in Example 1 was followed, except that in step 8), the elastomer film substrate was placed in a vacuum oxygen plasma treatment apparatus with a vacuum degree of 0.5 Pa and a power of 50 watts for 6 min of vacuum oxygen plasma treatment, while the elastomer film substrate was not subjected to additional treatment.

[0090] Figure 2 The atomic force microscope images of the quasi-continuous-microsphere morphology regulated by the stretchable quantum dot / elastomer hybrid photosensitive layer film prepared in Example 1 and the original morphology of the stretchable quantum dot / elastomer hybrid photosensitive layer film prepared in Comparative Example 2. Figure 2 It can be seen that by treating the substrate surface with oxygen plasma, the morphology of the stretchable quantum dot / elastomer hybrid film changes from the original needle-like morphology to the quasi-continuous-microsphere morphology, and the surface roughness of the film is reduced, which will promote the contact and carrier transport between the layers of the stretchable device.

[0091] Figure 3 Figures a and b are characteristic transfer curves of the stretchable broadband light-adaptive-synaptic transistors prepared in Example 1 and Comparative Example 1 under different 365nm illumination conditions. Compared with Comparative Example 1, after adding SEBS to the photosensitive layer of the stretchable broadband light-adaptive-synaptic transistor prepared in Example 1, the device light response can still be maintained at an extremely high level, and exhibits better sensitivity at lower light intensities. Figure 4 From the time-current comparison curves under single light pulses of Example 1 and Comparative Example 1, it can be seen that the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 can exhibit more ideal synaptic characteristics.

[0092] Figure 5 In the figure a, the visual bionic adaptive characteristic of Example 1 of the present invention is shown, which illustrates that the stretchable broadband light-adaptive-synaptic transistor prepared based on the quasi-continuous-microsphere morphology quantum dot / elastomer hybrid photosensitive layer can achieve self-adaptation to light intensity (the photocurrent gradually decays under strong light and gradually increases under weak light), and has gate voltage-dependent adjustable adaptive performance (the photocurrent gradually increases under positive operating voltage and gradually decays under negative operating voltage). Figure 5 Middle b and Figure 5 As shown in Figure c, the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 can still maintain relatively stable field effect performance and photoelectric response when subjected to 0-100% biaxial tensile strain and 0-1000 stretching cycles, and can still realize synaptic simulation and bionic visual adaptive functions, and when the tensile strain is released, the performance of the stretchable transistor returns to its initial value. Figure 6 It is proved that the stretchable wide-band light-adaptive-synaptic transistor prepared in Example 1 also has extremely excellent adjustable adaptive performance in the stretched state. Figure 7The images of the stretchable broadband light-adaptive-synaptic transistor prepared in Example 1 at different time intervals demonstrate its outstanding adaptive imaging performance. These experimental results demonstrate that the stretchable broadband light-adaptive-synaptic transistor prepared based on the quasi-continuous-microspherical quantum dot / elastomer hybrid photosensitive layer not only achieves high photoelectric response, but also has high resistance to mechanical deformation, excellent synaptic simulation, biomimetic visual adaptive functions and imaging effects, and provides a practical strategy for future wearable optoelectronic devices, electronic skin, brain-like neural computing, and biomimetic visual networks.

[0093] The present invention has been described in detail above. For those skilled in the art, without departing from the purpose and scope of the present invention, and without the need to carry out unnecessary experimental conditions, the present invention can be implemented in a wide range under equivalent parameters, concentrations and conditions. Although the present invention provides specific embodiments, it should be understood that further improvements can be made to the present invention. In short, according to the principles of the present invention, this application is intended to include any changes, uses or improvements to the present invention, including changes that depart from the disclosed scope in this application and are made using conventional techniques known in the art.

Claims

1. A stretchable broadband light-adaptive synaptic transistor having a bottom-gate top-contact structure, comprising, from bottom to top, the following components: A stretchable substrate, a stretchable gate electrode, a stretchable hybrid dielectric layer, a stretchable hybrid polymer semiconductor layer, a stretchable source electrode and a stretchable drain electrode in the same plane, and a stretchable quantum dot / elastomer hybrid photosensitive layer; The stretchable quantum dot / elastomer hybrid photosensitive layer is prepared by regulating the blending ratio, pre-aggregation morphology and self-assembly quasi-continuous-microsphere morphology of the photosensitive quantum dots and the elastomer polymer.

2. The stretchable broadband optically adaptive synaptic transistor according to claim 1, characterized in that: The self-assembled quasi-continuous-microsphere morphology is achieved by regulating the surface energy of the substrate; The surface energy of the substrate is achieved through vacuum oxygen plasma treatment, and the surface energy control range is 10-65 millijoules per square centimeter.

3. The stretchable broadband optically adaptive synaptic transistor according to claim 2, characterized in that: The substrate is a polydimethylsiloxane elastomer film substrate.

4. The stretchable broadband optically adaptive synaptic transistor according to any one of claims 1 to 3, characterized in that: The photosensitive quantum dots are any one of cesium lead chlorine quantum dots, cesium lead bromine quantum dots, cesium lead iodine quantum dots, cesium lead iodine quantum dots, cadmium telluride, cadmium sulfide and lead sulfide; The size of the photosensitive quantum dots is 1-10 nm; The elastomeric polymer is selected from any one of polydimethylsiloxane, hydrogenated styrene-butadiene block copolymer, polyurethane elastomer, styrene-butadiene rubber and natural rubber; The mass ratio of the photosensitive quantum dots to the elastomeric polymer is 10:0.5 to 10:3; The thickness of the stretchable quantum dot / elastomer hybrid photosensitive layer film is 10-50 nm.

5. The stretchable broadband optically adaptive synaptic transistor according to claim 1, characterized in that: The stretchable substrate is prepared from any one of the following elastomeric polymers: polydimethylsiloxane, hydrogenated styrene-butadiene block copolymer, polyurethane elastomer, styrene-butadiene rubber and natural rubber; The thickness of the stretchable substrate is 100 μm~2 mm; The stretchable gate electrode, the stretchable source electrode and the stretchable drain electrode are all made of carbon nanotube material or silver nanowire material; The stretchable hybrid dielectric layer is prepared by blending an elastomer and carbon quantum dots; The elastomeric polymer is selected from any one of polydimethylsiloxane, hydrogenated styrene-butadiene block copolymer, polyurethane elastomer, styrene-butadiene rubber and natural rubber; The size of the carbon quantum dots is 1-5 nm; The mixing mass ratio of the elastomeric polymer and the carbon quantum dots is 100:0.5 to 100:10; The thickness of the stretchable hybrid dielectric layer is 1300-2500 nm.

6. The stretchable broadband optically adaptive synaptic transistor according to claim 1, characterized in that: The stretchable hybrid polymer semiconductor layer is prepared from a stretchable hybrid polymer blend system of an elastomeric polymer and a conjugated polymer; The elastomeric polymer is selected from any one of polydimethylsiloxane, hydrogenated styrene-butadiene block copolymer, polyurethane elastomer, styrene-butadiene rubber and natural rubber; The conjugated polymer is any one of poly(2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)diketopyrrolo[3,4-c]pyrrole-1,4-dione-alt-thiophene[3,2-b]thiophene) (DPPT-TT), poly(2,5-bis(3-alkylthiophen-2-yl)thiophene[3,2-b]thiophene) (PBTTT), poly(tetrathiopheneacetic acid diketopyrrole) (PTDPPTFT4), polyisoindigodithiophene (PII2T) and poly(3-hexylthiophene) (P3HT); The mass ratio of the conjugated polymer to the elastomeric polymer is 1:9 to 9:1; The thickness of the stretchable hybrid polymer semiconductor layer is 30-100 nm.

7. A method for preparing the stretchable broadband optically adaptive synaptic transistor according to any one of claims 1 to 6, comprising the following steps: (1) preparing the stretchable substrate, the stretchable gate electrode, the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer, the stretchable source electrode and the stretchable drain electrode on the substrate with the self-assembled molecular layer respectively; (2) preparing the stretchable quantum dot / elastomer hybrid photosensitive layer on a substrate having a polydimethylsiloxane (PDMS) elastomer film that has been surface-treated by vacuum oxygen plasma; (3) Using tweezers, the stretchable substrate is transferred from the substrate with the self-assembled molecular layer, and then the stretchable substrate is covered on the stretchable gate electrode from one side; The stretchable gate electrode is transferred to the stretchable substrate by a thermal bonding-transfer method; then, the same method and steps are used to sequentially transfer the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer, the stretchable source electrode and the stretchable drain electrode located on the same plane, and the stretchable quantum dot / elastomer hybrid photosensitive layer from a self-assembled monolayer substrate or a substrate with an elastomer film to the stretchable gate electrode, thereby obtaining a stretchable wide-band light-adaptive-synaptic transistor based on a morphology-controllable quasi-continuous quantum dot / elastomer hybrid photosensitive layer.

8. The method according to claim 7, wherein: The substrate is selected from any one of silicon wafer, glass, ceramic and quartz; The substrate with the self-assembled molecular layer is prepared by heating the substrate with any one of octadecyltrimethoxysilane, octadecyltrichlorosilane, octadecyltrichlorosilane and phenyltrichlorosilane under vacuum conditions or immersing the substrate in a solution; The elastic film substrate is obtained by cross-linking and diluting a polydimethylsiloxane (PDMS) stock solution, a cross-linking agent and a solvent in a proportion, depositing the solution on the substrate, and then treating the solution with vacuum oxygen plasma. Wherein, the mass ratio of the polydimethylsiloxane (PDMS) stock solution to the cross-linking agent is 10:1 to 20:1; The mass ratio of the mixed solution of the polydimethylsiloxane (PDMS) stock solution and the cross-linking agent to the solvent is 1:5 to 1:10; The solvent is any one of cyclohexane, n-hexane, isohexane, and toluene; The thickness of the elastomer film substrate is 500-3000 nm; The vacuum oxygen plasma treatment has a vacuum degree of 0.3-0.8 Pascal, a power of 10-30 W, and a treatment time of 0.5-10 min.

9. The method according to claim 7, wherein: The stretchable substrate, the stretchable hybrid dielectric layer, the stretchable hybrid polymer semiconductor layer and the stretchable quantum dot / elastomer hybrid photosensitive layer film are prepared by a solution deposition method; The solution deposition method is any one of drop coating, spin coating, blade coating, roll coating, brush coating and film drawing; The solvent used in the solution deposition method is toluene, xylene, methane, chloroform, dichloromethane, n-hexane or cyclohexane; The solution concentration of the stretchable substrate is 100-300 mg / mL; The solution concentration of the stretchable hybrid dielectric layer is 50-100 mg / mL; The solution concentration of the stretchable hybrid polymer semiconductor layer is 5-15 mg / mL; The solution concentration of the stretchable quantum dot / elastomer hybrid photosensitive layer is 5-15 mg / mL; The stretchable gate electrode, the stretchable source electrode and the stretchable drain electrode are all made by a spray coating method; The spraying conditions are as follows: the temperature of the substrate is 60-120 °C, the distance between the spray gun nozzle and the substrate is 5-12 cm, the spraying rate is 0.3-3 mL / min, and the spraying volume is 1-3 mL.

10. The method according to claim 7, wherein: The thermal bonding process is carried out in a vacuum drying oven; The conditions for the thermal bonding are: a vacuum degree of 0.1 to 3 Pascals, a temperature during the heating treatment of 30 to 80 ° C, and a heating treatment time of 0.1 to 1 hour.

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