Self-driven bionic vision-touch fusion sensor array and preparation method thereof
By combining photoelectric synaptic transistors with triboelectric nanogenerators, a self-driven vision-touch fusion sensor array was realized, solving the problems of single sensor function and insufficient flexibility in existing technologies. It achieves low power consumption, self-powering, and high-precision sensing, and is suitable for smart sensors and wearable devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-04-21
AI Technical Summary
In existing technologies, self-driven tactile sensors based on triboelectric nanogenerators have limited functionality and lack brain-like information processing capabilities. Visual sensors based on photoelectric synaptic transistors lack flexibility, resulting in bulky system structures, low integration, and large signal transmission delays and losses, making it difficult to achieve low-power self-powered and high-density flexible arrays.
By combining photoelectric synaptic transistors with triboelectric nanogenerators and using a material with double-layer capacitance effect as the gate dielectric layer, the organic integration of triboelectric nanogenerators and photoelectric synaptic transistors is achieved. The contact-separation motion between the triboelectric layer and the gate dielectric layer generates a self-driven fusion of tactile and visual signals. The channel conductivity is controlled by photogenerated carriers and triboelectric potential to achieve a self-driven bionic tactile function under low voltage.
It achieves low-power, self-powered visual-tactile fusion perception with rapid response capabilities, and is suitable for low-power smart sensors, neuromorphic computing, and wearable devices. It fills the gap in visual-tactile perception in extreme environments and improves perception accuracy and sensitivity.
Smart Images
Figure CN121898524A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of biomimetic intelligent sensing technology, specifically relating to a self-driven biomimetic vision-touch fusion sensor array and its fabrication method. Background Technology
[0002] Bionic intelligent sensing technology, by simulating the multi-sensory fusion cognitive mechanism of humans, aims to endow robots with similar information perception and intelligent decision-making capabilities, and is a core frontier driving the development of artificial intelligence, robotics, and wearable devices. Among these advancements, the development of flexible sensor arrays capable of simultaneously sensing and fusing tactile and visual information is considered crucial for achieving efficient human-computer interaction and adaptability to complex environments, possessing significant research value and application prospects.
[0003] Currently, research in this field is mainly developing along two paths: one is self-driven tactile sensors based on triboelectric nanogenerators, which can convert mechanical energy into electrical signals, but have a single function and lack brain-like information processing capabilities; the other is visual sensors based on photoelectric synaptic transistors, which can simulate the perception and memory of visual information, but most of them are built on rigid substrates, lack flexibility, and their applications in wearable and implantable devices are limited, which greatly restricts their application in bionics.
[0004] To achieve sensory fusion, independent tactile and visual sensors are typically combined with backend signal processing units in a discrete manner. For example, a resistive pressure sensor, a photodetector, and a hydrogel ion cable are connected, and then a synaptic transistor is used for signal integration. However, this discrete fusion scheme has significant drawbacks: First, the complex interconnection of multiple components leads to a bulky system structure, low integration, and introduces signal transmission delay and loss; second, the tactile unit relies on an external power supply, making it difficult to achieve low power consumption and self-powering; finally, this non-integrated structure is not conducive to building high-density flexible arrays, severely limiting its practical application in scenarios such as bionic electronic skin that requires spatially discriminative perception. Summary of the Invention
[0005] To address the aforementioned problems in the prior art, this invention provides a self-driven bionic vision-touch fusion sensor array and its fabrication method. The technical problem to be solved by this invention is achieved through the following technical solution: This invention provides a self-driven bionic vision-touch fusion sensor array, comprising: a flexible substrate and at least one sensing unit disposed on the flexible substrate, wherein the sensing unit comprises: a photosynaptic transistor and a triboelectric nanogenerator; The flexible substrate includes a first flexible substrate and a second flexible substrate that are spaced apart from each other, and the first flexible substrate and the second flexible substrate are supported by an elastic medium. The photoelectric synaptic transistor includes a photosensitive semiconductor layer, a source electrode, a drain electrode, and a gate dielectric layer. The photosensitive semiconductor layer is disposed on the surface of the first flexible substrate close to the second flexible substrate. The source electrode and the drain electrode are disposed at intervals on the surface of the photosensitive semiconductor layer. The gate dielectric layer covers the surfaces of the photosensitive semiconductor layer, the source electrode, and the drain electrode. The gate dielectric layer also serves as the charge storage layer of the triboelectric nanogenerator; The triboelectric nanogenerator includes a triboelectric layer disposed on the surface of the second flexible substrate near the first flexible substrate and spaced apart from the gate dielectric layer. Under the action of external force, the triboelectric layer undergoes contact-separation motion with the gate dielectric layer.
[0006] This invention also provides a method for fabricating a self-driven bionic vision-touch fusion sensor array, applicable to the self-driven bionic vision-touch fusion sensor array described in any of the above embodiments, the fabrication method comprising: A photosensitive semiconductor layer is formed on the surface of the first flexible substrate; A source electrode and a drain electrode are formed on the photosensitive semiconductor layer; A gate dielectric layer is fabricated on the source electrode, the drain electrode, and the photosensitive semiconductor layer, and the gate dielectric layer also serves as the charge storage layer of the triboelectric nanogenerator; wherein, the gate dielectric layer forms an electric double layer under external stimulation to generate a tactile stimulation response, and the photosensitive semiconductor layer generates photogenerated carriers regulated by the electric double layer under light stimulation to increase the synaptic current; A friction layer is formed on the surface of the second flexible substrate; The friction layer is supported above the gate dielectric layer by an elastic medium, and the friction layer and the gate dielectric layer are spaced apart and opposite each other.
[0007] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The self-driven bionic vision-touch fusion sensor array of the present invention combines a triboelectric nanogenerator with a photoelectric synaptic transistor, and uses a material with a double-layer capacitance effect as the gate dielectric layer to form a double-layer structure at the interface, enabling the transistor to operate at low voltages (V). DS It operates at 0.1V. The gate dielectric layer also serves as the triboelectric nanogenerator, realizing a true organic combination of the triboelectric nanogenerator and the photoelectric synaptic transistor. By using different triboelectric layer materials, the gate voltage is provided directly by friction on the gate dielectric layer. Excitatory postsynaptic current is generated between the source and drain electrodes without external power supply, realizing a self-driven bionic tactile function.
[0008] 2. This invention relates to a self-driven bionic vision-tactile fusion sensor array, which has the ability to perceive both external tactile and visual stimuli separately. It can combine tactile and visual stimuli to achieve more accurate perception of the external environment, filling the gap in visual and tactile perception of the external environment under extreme conditions. It also features rapid response capabilities, simple constituent units, low cost, low power consumption, and ease of integration into arrays. It is particularly suitable for low-power, self-powered intelligent sensors, neuromorphic computing, and wearable devices.
[0009] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above description and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description
[0010] Figure 1 This is a 3D structural diagram of a self-driven bionic vision-touch fusion sensor array provided in an embodiment of the present invention; Figure 2 This is a cross-sectional view of a sensing unit provided in an embodiment of the present invention; Figure 3 This is a structural diagram of a photoelectric synaptic transistor provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the tactile perception principle provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the visual perception principle provided in an embodiment of the present invention.
[0011] Icons: 1-First flexible substrate; 2-Second flexible substrate; 3-Photosensitive semiconductor layer; 4-Source electrode; 5-Drain electrode; 6-Gate dielectric layer; 7-Tribology layer; 8-Elastic dielectric. Detailed Implementation
[0012] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following describes in detail, with reference to the accompanying drawings and specific embodiments, a self-driven bionic vision-touch fusion sensor array and its preparation method proposed according to the present invention.
[0013] The foregoing and other technical contents, features, and effects of the present invention will be clearly presented in the following detailed description of specific embodiments in conjunction with the accompanying drawings. Through the description of the specific embodiments, a more in-depth and concrete understanding can be gained of the technical means and effects adopted by the present invention to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit the technical solutions of the present invention.
[0014] Firstly, embodiments of the present invention provide a self-driven bionic vision-touch fusion sensor array. (See also...) Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a 3D structural diagram of a self-driven bionic vision-touch fusion sensor array provided in an embodiment of the present invention; Figure 2 This is a cross-sectional view of a sensing unit provided in an embodiment of the present invention; Figure 3 This is a structural diagram of a photoelectric synaptic transistor provided in an embodiment of the present invention.
[0015] The self-driven bionic vision-touch fusion sensor array of this embodiment includes: a flexible substrate and at least one sensing unit disposed on the flexible substrate, the sensing unit including: a photosynaptic transistor and a triboelectric nanogenerator. Figure 1 As shown, the flexible substrate includes a first flexible substrate 1 and a second flexible substrate 2 arranged at a relative interval, and the first flexible substrate 1 and the second flexible substrate 2 are supported by an elastic medium 8.
[0016] In this embodiment, when the sensor array includes multiple sensing units, the sensing units are arranged in an M×N matrix on the flexible substrate, where M and N are both integers greater than or equal to 2. The connections between the sensing units can be made using conventional metal wiring, flexible printed circuits, or conductive polymers.
[0017] For example, such as Figure 1 As shown, the self-driven bionic vision-touch fusion sensor array includes eight sensing units arranged in a 2×4 matrix on a flexible substrate.
[0018] like Figure 3 As shown, the photoelectric synaptic transistor includes a photosensitive semiconductor layer 3, a source electrode 4, a drain electrode 5, and a gate dielectric layer 6. The photosensitive semiconductor layer 3 is disposed on the surface of the first flexible substrate 1 close to the second flexible substrate 2. The source electrode 4 and the drain electrode 5 are disposed at intervals on the surface of the photosensitive semiconductor layer 3. The gate dielectric layer 6 covers the surfaces of the photosensitive semiconductor layer 3, the source electrode 4, and the drain electrode 5. In this embodiment, the gate dielectric layer 6 is made of a material capable of forming an electric double layer, and also serves as the charge storage layer of the triboelectric nanogenerator. The material of the gate dielectric layer 6 includes one or more of the following: electrolyte solution, ionic liquid, ionic gel, ion-conducting polymer, and proton-conducting polymer.
[0019] like Figure 2 As shown, the triboelectric nanogenerator includes a triboelectric layer 7, which is disposed on the surface of a second flexible substrate 2 near the first flexible substrate 1 and spaced apart from the gate dielectric layer 6. Under the action of external force, it undergoes contact-separation movement with the gate dielectric layer 6.
[0020] In this embodiment, the photosensitive semiconductor layer 3 generates photogenerated carriers under illumination. Illumination causes these carriers to persist for a relatively long time, resulting in continuous changes in channel conductivity, thereby enabling the perception and memorization of visual information. When the tribological layer 7 and the gate dielectric layer 6 undergo contact-separation motion, a triboelectric potential is generated in the gate dielectric layer 6, thereby regulating the conductivity state of the photosensitive semiconductor layer 3 and achieving self-driven tactile perception.
[0021] In this embodiment, the gate dielectric layer 6 of the photosynaptic transistor simultaneously serves as the charge storage layer of the triboelectric nanogenerator, thereby achieving the organic integration of the photosynaptic transistor and the triboelectric nanogenerator. Through the periodic contact and separation of the triboelectric layer 7 and the gate dielectric layer 6, a pulse voltage is generated. This pulse voltage acts on the semiconductor surface, thereby altering its conductivity. A synaptic current can be generated between the source and drain without an external power source, completing a self-driven biomimetic tactile sensing. When the sensing unit simultaneously receives light and mechanical friction stimulation, the gate dielectric layer 6 is simultaneously subjected to potential modulation generated by the triboelectric layer and carrier injection generated by light. The visual signal and the tactile signal work together at the interface between the gate dielectric layer 6 and the photosensitive semiconductor layer 3 to produce a fusion effect. The voltage signal generated by friction guides the migration and redistribution of ions within the gate dielectric layer. Due to the network structure inside the gate dielectric layer (ion gel) and the low carrier mobility of the ion gel, it can maintain the double-layer state. The change in the double layer caused by different voltages simulates the synaptic behavior of biological organisms and regulates synaptic weights. The carrier injection induced by light further enhances the channel conductivity. For photosensitive semiconductors, light of a specific wavelength will generate photogenerated carriers inside the photosensitive semiconductor. For phototransistors, these carriers generally require a higher activation energy to undergo non-spontaneous recombination, thus regulating synaptic weights under light stimulation. The two stimuli produce a synergistic enhancement effect, and the output postsynaptic current is much higher than that of a single stimulus, exhibiting brain-like characteristics of "stimulus superposition" and "coupled learning".
[0022] The principle can be understood as follows: When the tactile-visual perception unit is simultaneously stimulated by mechanical and optical stimuli, for external mechanical stimulation, the ion gel gate forms an electric double layer. Negative charges accumulate on the ion gel surface near the photosensitive semiconductor layer, while positive charges accumulate on the ion gel gate dielectric layer surface near the friction layer. For external optical stimulation, photogenerated carriers are generated when the semiconductor layer is illuminated, i.e., photogenerated holes and photogenerated electrons are generated simultaneously. The contact area between the gate dielectric layer (ion gel) and the semiconductor layer itself accumulates negative charges, leading to the accumulation of holes on the semiconductor surface near the ion gel. These holes, along with the negative charges on the ion gel surface, form a stable structure. This structure allows the ion gel to... The ion-gel double layer exhibits stronger non-volatility, resulting in a longer duration of synaptic currents generated by external stimuli. Under proper control and regulation of the ion-gel gate, the current variation is also greater than that of single light or mechanical stimulation. It is important to note that the gate medium made of ion-gel has strong gate control capabilities. During the formation of the double layer, it attracts charge carriers from inside the semiconductor to the surface where the semiconductor and the ion-gel gate medium meet. At this time, the interface states affect the carrier mobility, leading to a decrease in the transistor channel conductivity, i.e., a negative photoconductivity effect. This may result in the simultaneous action of light and tactile stimulation, preventing the synergistic enhancement effect of the synaptic current.
[0023] It should be noted that the negative photoconductivity phenomenon can be reduced and the synergistic enhancement effect improved by decreasing the gate control capability of the gate dielectric layer (ion gel). A direct method is to appropriately reduce the concentration of conductive ions within the ion gel. However, reducing the concentration of conductive ions within the gel will decrease the device response speed. To improve the sensing sensitivity to mechanical signals with frequencies below 100 Hz, the content of ionic liquid in the polymer matrix should be no less than 10 wt% and no more than 50 wt%. This behavior can simulate multimodal integration in the nervous system (such as visual-tactile linkage, associative learning, and sensory enhancement), achieving visual-tactile fusion perception. Simultaneously, by adjusting the magnitude of the triboelectric potential, the conductance of the semiconductor layer channel caused by illumination can be precisely controlled, organically combining tactile perception with visual perception, which can significantly improve the accuracy and sensitivity of image perception.
[0024] In an optional embodiment, the flexible substrate (first flexible substrate 1, second flexible substrate 2) is made of one of the following materials: hydrogel, polyimide, polyethylene naphthalate, polyethylene terephthalate, polydimethylsiloxane, and polycarbonate.
[0025] In this embodiment, a triboelectric generator with a flexible substrate is used to drive a phototransistor, providing a foundation and guarantee for the fit and wearability of the electronic skin.
[0026] In an optional embodiment, the material of the photosensitive semiconductor layer 3 is a photosensitive amorphous oxide semiconductor material, including IGZO and InO. x ZnOx SnO x One of IZO, ZnSnO, nanowire IGZO and quantum dot modified IGZO.
[0027] Understandably, the photosensitive semiconductor layer 3 serves as the channel layer of the phototransistor, and the photosensitive amorphous oxide semiconductor material possesses excellent light absorption capabilities. Oxygen vacancies exist in the photosensitive amorphous oxide semiconductor. Under illumination, these oxygen vacancies induce deep-trapped states that decompose into photogenerated electrons and negatively charged oxygen vacancy ions. These photogenerated electrons require high activation energy to undergo non-spontaneous recombination; therefore, when illumination is removed, these photoelectrons will slowly decay, thereby reducing the semiconductor layer resistance, increasing the current, and achieving the postsynaptic current response of the channel. Illumination enhances the drain-source current, similar to the postsynaptic current of a synapse. Synaptic plasticity can be controlled by changing parameters such as light intensity, irradiation time, and wavelength.
[0028] In an optional embodiment, the source and drain electrodes are made of one of Al, ITO, Au, Cr-Au, and Ti-Au materials.
[0029] In an optional embodiment, the material of the gate dielectric layer 6 is a material with an electric double layer capacitance effect. Optionally, the material of the gate dielectric layer 6 includes one or more of electrolyte solutions, ionic liquids, ionic gels, ionic conductive polymers, and proton conductive polymers.
[0030] For example, electrolyte solutions include PBS buffer and aqueous solutions of NaCl or KCl; ionic liquids include 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide and N-butyl-N-methylpyrrolidone ononium tri(pentafluoroethyl)trifluorophosphate; ionic gels include polyvinylidene fluoride-co-hexafluoropropylene / 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ionic gel, polymethyl methacrylate / 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ionic gel; ion-conducting polymers include polyethylene oxide, polyvinylidene fluoride-co-hexafluoropropylene, etc.; and proton-conducting polymers include sulfonated polyetheretherketone, polybenzimidazole, etc.
[0031] In an optional embodiment, the friction layer 7 has a planar structure, a pyramidal microstructure, or a cylindrical microstructure. The microstructure of the friction layer 7 can enhance the output voltage and current. The material of the friction layer 7 is either a negative or positive material in the triboelectric electrode sequence; the negative material includes one of polytetrafluoroethylene, polypropylene, polyethylene, polydimethylsiloxane, and polyimide; the positive material includes one of nylon, silk, wool, and metal foil.
[0032] It is understandable that using a material with double-layer capacitance effect as both the gate dielectric layer 6 of the phototransistor and the charge storage layer of the triboelectric nanogenerator allows for direct functional integration of the triboelectric nanogenerator and the phototransistor into a single device. The triboelectric nanogenerator simultaneously functions as an energy harvesting device and a sensor to collect external tactile information, reducing dependence on external power sources and enabling partially or even fully self-powered operation. The material with double-layer capacitance effect forms a double-layer structure at the interface as the gate dielectric layer 6, allowing the transistor to operate at low voltages (V... DS Operating at 0.1V, the ion concentration and distribution of the semiconductor layer are controlled by the gate voltage, thereby regulating the transistor's conductivity. Through the contact-separation motion between the friction layer 7 and the gate dielectric layer 6, an equivalent gate voltage regulating channel conductance is directly generated at the gate dielectric layer-amorphous oxide semiconductor interface, achieving the conversion of tactile stimulation to synaptic current and synaptic-like response without an external power supply. This regulation is similar to the neurotransmitter release and receptor binding process in biological synapses, thus enabling functions similar to biological synapses. On the same device (gate dielectric layer-amorphous oxide semiconductor interface), optical stimulation and frictional stimulation work synergistically to generate a nonlinearly superimposed (greater than the sum of individual stimuli) output synaptic current, achieving brain-like fusion perception and learning of visual and tactile information (such as stimulus superposition and coupled learning).
[0033] In an alternative embodiment, the material of the elastic medium 8 includes one of a spring, a rubber column, a silicone microsphere, and an elastic fiber, for providing the restoring force required for the contact-separation movement between the friction layer 7 and the gate dielectric layer 6.
[0034] The self-driven bionic vision-touch fusion sensor array of this invention combines a triboelectric nanogenerator with a photoelectric synaptic transistor and uses a material with a double-layer capacitance effect as the gate dielectric layer to form a double-layer structure at the interface, enabling the transistor to operate at low voltages (V). DS It operates at 0.1V. The gate dielectric layer also serves as the triboelectric nanogenerator, achieving a true organic integration of the triboelectric nanogenerator and the photoelectric synaptic transistor. By using different triboelectric layer materials, the gate voltage is directly provided by friction on the gate dielectric layer. Excitatory postsynaptic currents are generated between the source and drain electrodes without external power supply, realizing self-driven bionic tactile function. Moreover, it has the ability to perceive external tactile and visual stimuli separately, and can combine tactile and visual stimuli to achieve more accurate perception of the external environment, filling the gap in visual and tactile perception of the external environment in extreme environments. It also has rapid response capability, simple constituent units, and is conducive to integrated array. It is particularly suitable for low-power, self-powered smart sensors, neuromorphic computing, and wearable devices.
[0035] Furthermore, taking a single sensing unit as an example, the principles of vision, touch, and fusion perception of the self-driven bionic vision-touch fusion sensor array in this embodiment will be explained.
[0036] Please see Figure 4 , Figure 4 This is a schematic diagram of the tactile sensing principle provided in an embodiment of the present invention. In the sensor, the gate dielectric layer 6 of the ion gel material and the friction layer 7 together constitute a triboelectric nanogenerator structure. When an external force causes the friction layer 7 and the gate dielectric layer 6 to come into contact and separate, equal amounts of opposite electrostatic charges will be generated at the interface based on the difference in electron affinity between the materials. Figure 4 As shown in Figure (a), when a negative triboelectric electrode sequence material (such as polytetrafluoroethylene or polydimethylsiloxane) is selected for the triboelectric layer, a positive charge is induced at the ion gel interface. During the dynamic change of the porosity of the triboelectric nanogenerator, a potential difference is formed within the ion gel, inducing positive ions to migrate directionally towards the channel. A positive charge accumulation region is formed at the interface between the ion gel and the photosensitive semiconductor layer 3, which is equivalent to applying a positive gate voltage. This causes the semiconductor surface energy band of the contact gate dielectric layer to bend downwards. Since this device is an N-type depletion-type device, the downward bending of the semiconductor surface energy band increases the carrier concentration, and the device exhibits enhanced conductivity. Conversely, as... Figure 4 As shown in Figure (b), when the friction layer is made of a positive triboelectric electrode sequence material (such as nylon or wool), the ionogel senses a negative charge. Internal negative ions migrate towards the semiconductor interface, equivalent to applying a negative gate voltage. This causes the semiconductor surface energy band of the channel contact gate dielectric layer to bend upwards, increasing the distance between the Fermi level and the conduction band, thus decreasing the carrier concentration and reducing channel conductivity. This triboelectric sensing process essentially converts external mechanical stimulation into an electrical signal that regulates channel conductivity, simulating the biological process of presynaptic neurons releasing neurotransmitters and regulating synaptic weights at the postsynaptic membrane. Because the migration and distribution of ions in the ionogel can be maintained for a short time, it possesses synaptic-like short-term memory (STP) or long-term enhancement (LTP) characteristics, enabling the sensor to not only respond to external mechanical signals but also perform brain-like information processing.
[0037] Please see Figure 5 , Figure 5This is a schematic diagram of the visual perception principle provided in an embodiment of the present invention. The channel layer material of the phototransistor is a photosensitive amorphous oxide semiconductor material, which has good light absorption capability. The photosensitive amorphous oxide semiconductor contains oxygen vacancies. Under illumination, these oxygen vacancies induce deep trap states that decompose into photogenerated electrons and negatively charged oxygen vacancy ions. These photogenerated electrons require high activation energy to undergo non-spontaneous recombination. Therefore, when the light is removed, these photoelectrons will continue to decay slowly, simulating the biological process of presynaptic neurons releasing neurotransmitters and regulating synaptic weights at the postsynaptic membrane, thus realizing the postsynaptic current response of the channel. Through this characteristic, the phototransistor can convert incident light signals into synaptic electrical signals, acting as a photodetector to capture visual information, simulating the short-term or long-term enhancement effects of biological synapses. Light intensity, wavelength, and duration can all be used as adjustment parameters to control the amplitude and duration of the postsynaptic current.
[0038] Based on the principles of visual and tactile perception described above, when the sensor simultaneously receives both light and frictional stimuli, the two signals interact at the same gate dielectric layer—the amorphous oxide semiconductor interface—producing a fusion effect. The voltage signal generated by friction induces ion migration, while the carrier injection induced by light further enhances the channel conductivity. The two stimuli produce a synergistic enhancement effect, resulting in a postsynaptic current far higher than the superposition of two single stimuli. This exhibits brain-like characteristics of "stimulus superposition" and "coupled learning." This behavior can simulate multimodal integration in the nervous system, improving image contrast and greatly enhancing the accuracy of the sensor's perception of the external environment. It also significantly expands the sensor's application scenarios under extreme multidimensional conditions, enabling three-dimensional perception of external object images and pressure.
[0039] Secondly, embodiments of the present invention provide a method for fabricating a self-driven bionic vision-touch fusion sensor array, applicable to the self-driven bionic vision-touch fusion sensor array provided in the first aspect. The method for fabricating the self-driven bionic vision-touch fusion sensor array of this embodiment includes the following steps: Step 1: Form a photosensitive semiconductor layer on the surface of the first flexible substrate.
[0040] Optionally, the material of the first flexible substrate includes any one of hydrogel, polyimide, polyethylene naphthalate, polyethylene terephthalate, polydimethylsiloxane, and polycarbonate.
[0041] Optionally, the material of the photosensitive semiconductor layer is a photosensitive amorphous oxide semiconductor material, including IGZO and InO. x ZnO x SnO x One of IZO, ZnSnO, nanowire IGZO and quantum dot modified IGZO.
[0042] Optionally, the photosensitive semiconductor layer is prepared by radio frequency magnetron sputtering with a sputtering power of 80-120W and a working pressure of 0.3-0.6Pa.
[0043] Step 2: Form source and drain electrodes on the photosensitive semiconductor layer.
[0044] Optionally, the source and drain electrodes may be made of any one of Al, ITO, Au, Cr-Au, and Ti-Au.
[0045] Optionally, the source electrode and drain electrode are prepared by radio frequency magnetron sputtering with a sputtering power of 80-120W and a working gas pressure of 0.5-0.8Pa.
[0046] Step 3: Fabricate a gate dielectric layer on the source electrode, drain electrode, and photosensitive semiconductor layer. The gate dielectric layer also serves as the charge storage layer for the triboelectric nanogenerator.
[0047] Among them, the gate dielectric layer forms an electric double layer under external stimulation, generating a tactile stimulation response, and the photosensitive semiconductor layer generates photogenerated carriers regulated by the electric double layer under light stimulation, further increasing the synaptic current; The gate dielectric layer is made of a material with double-layer capacitance effect. Optionally, the material of the gate dielectric layer includes one or more of electrolyte solution, ionic liquid, ionic gel, ionic conductive polymer and proton conductive polymer.
[0048] In this embodiment, different concentrations of ionic liquids can be selected for the gate dielectric layer to address the negative photoconductivity phenomenon. The ionic liquid should be an imidazole-based ionic liquid, such as 1-hexyl-3-methylimidazolium bromide ((HMIM)Br), 1-hexyl-3-vinylimidazolium bromide ((HVIM)Br) solution, 1-ethyl-3-methylimidazolium chloride ((EMIM)Cl) solution, 1-allyl-3-methylimidazolium chloride ((AMIM)Cl) solution, 1-ethyl-3-methylimidazolium-bis(trifluoromethanesulfonyl)imine ([EMIM][TFSI]) solution, etc. The content of the ionic liquid in the polymer matrix should be not less than 10 wt% and not more than 50 wt%.
[0049] Step 4: Form a friction layer on the surface of the second flexible substrate.
[0050] Optionally, similar to the first flexible substrate, the material of the second flexible substrate includes any one of hydrogel, polyimide, polyethylene naphthalate, polyethylene terephthalate, polydimethylsiloxane, and polycarbonate.
[0051] Optionally, the structure of the friction layer is a planar structure, a pyramidal microstructure, or a cylindrical microstructure. The material of the friction layer is a negative or positive material in the triboelectric electrode sequence, wherein the negative material includes one of polydimethylsiloxane, polyethylene, polytetrafluoroethylene, polypropylene, and polyimide; and the positive material includes one of nylon, silk, wool, and metal foil.
[0052] Step 5: Support the friction layer above the gate dielectric layer using an elastic medium, with the friction layer and the gate dielectric layer spaced apart and opposite each other.
[0053] Optionally, the material of the elastic medium includes one of springs, rubber pillars, silicone microspheres, and elastic fibers, used to provide the restoring force required for the contact-separation motion between the friction layer and the gate dielectric layer.
[0054] Furthermore, the fabrication method of the self-driven bionic vision-touch fusion sensor array of the present invention will be described in detail through specific examples.
[0055] Fabrication of photosynaptic transistor arrays: Step 1: Select a 150μm thick flexible polyethylene terephthalate (PET) film as the flexible substrate. Immerse it sequentially in acetone, isopropanol, and deionized water, then ultrasonically clean for 15 minutes each to thoroughly remove surface organic matter and particulate contaminants. After cleaning, dry the substrate surface with high-purity nitrogen gas for later use.
[0056] Step 2: A photosensitive amorphous oxide semiconductor layer is deposited on the cleaned PET substrate using an RF magnetron sputtering system. Specifically, an indium gallium zinc oxide (IGZO) ceramic target is used, and sputtering is performed at room temperature. The process parameters are set as follows: RF power 100W, cavity sputtering pressure 0.45Pa, and argon to oxygen flow rate ratio of 20:1 (total flow rate 30 sccm). By controlling the sputtering time, an IGZO thin film with a thickness of 15nm is obtained. This film is the photosensitive semiconductor layer of the phototransistor.
[0057] Step 3: Using a mask, a patterned aluminum (Al) layer is deposited on the IGZO layer using an RF magnetron sputtering system to form the source and drain electrodes. Process parameters are: RF power 85W, cavity sputtering pressure 0.5Pa, pure argon atmosphere (flow rate 20 sccm). The channel between the source and drain electrodes is designed to be 125 μm wide and 1600 μm long.
[0058] Step 4: First, prepare the ionogel precursor solution: Accurately weigh and mix vinylidene fluoride-hexafluoropropylene (P(VDF-HFP)), 1-ethyl-3-methylimidazolium-bis(trifluoromethanesulfonyl)imide ([EMIM][TFSI]), and solvent acetone in a mass ratio of 1:4:6. Then, use a magnetic stirrer to continuously stir at 60 °C and 1000 rpm for about 6 hours until the mixture forms a homogeneous, transparent, viscous solution.
[0059] Then, the above-mentioned ion gel precursor solution is printed and covered on the entire active region including the source electrode, drain electrode and IGZO channel by screen printing technology, so that it is fully filled and covered to form an ion gel layer. This layer serves as both the gate dielectric layer of the photoelectric synaptic transistor and the charge storage layer of the triboelectric nanogenerator.
[0060] Partial fabrication of the triboelectric nanolayer array: Step 1: Select polyethylene terephthalate (PET) film as the flexible substrate. Immerse it sequentially in acetone, isopropanol, and deionized water, then ultrasonically clean for 15 minutes each to thoroughly remove surface organic matter and particulate contaminants. After cleaning, dry the substrate surface with high-purity nitrogen gas for later use.
[0061] Step 2: Select polydimethylsiloxane (PDMS) as the friction layer material. Mix PDMS and curing agent at a mass ratio of 10:1 and stir for 20 minutes to ensure uniform mixing. Then, place the mixture in a vacuum drying oven for 20 minutes to degas and remove air bubbles introduced during stirring.
[0062] Step 3: Spin-coat the degassed PDMS mixture onto the PET substrate at 500 rpm for 60 seconds, then place it on a hot plate at 85°C to cure for 1 hour to form a PDMS film, i.e., the friction layer.
[0063] Array integration: Springs are fixed at the four corners of a PET substrate with a PDMS friction layer, and then inverted and aligned with the substrate on which the transistor array has been fabricated, ensuring that the PDMS friction layer is precisely positioned above the ionogel layer, and maintaining an initial gap of at least 200 μm between the friction layer and the ionogel layer. This forms a complete sensor unit and array capable of contact-separation.
[0064] For details regarding the fabrication method of the self-driven bionic vision-touch fusion sensor array and its corresponding beneficial effects, please refer to the relevant content on the self-driven bionic vision-touch fusion sensor array provided in the first aspect; it will not be repeated here.
[0065] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that an article or device comprising a list of elements includes not only those elements but also other elements not expressly listed. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device comprising said element. Terms such as "connected" or "linked" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect. The orientations or positional relationships indicated by terms such as "upper," "lower," "left," and "right" are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.
[0066] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.
[0067] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.
Claims
1. A self-driven bionic vision-touch fusion sensor array, characterized in that, include: A flexible substrate and at least one sensing unit disposed on the flexible substrate, the sensing unit comprising: a photosynaptic transistor and a triboelectric nanogenerator; The flexible substrate includes a first flexible substrate and a second flexible substrate that are spaced apart from each other, and the first flexible substrate and the second flexible substrate are supported by an elastic medium. The photoelectric synaptic transistor includes a photosensitive semiconductor layer, a source electrode, a drain electrode, and a gate dielectric layer. The photosensitive semiconductor layer is disposed on the surface of the first flexible substrate close to the second flexible substrate. The source electrode and the drain electrode are disposed at intervals on the surface of the photosensitive semiconductor layer. The gate dielectric layer covers the surfaces of the photosensitive semiconductor layer, the source electrode, and the drain electrode. The gate dielectric layer also serves as the charge storage layer of the triboelectric nanogenerator; The triboelectric nanogenerator includes a triboelectric layer disposed on the surface of the second flexible substrate near the first flexible substrate and spaced apart from the gate dielectric layer. Under the action of external force, the triboelectric layer undergoes contact-separation motion with the gate dielectric layer.
2. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, The flexible substrate is made of one of the following materials: hydrogel, polyimide, polyethylene naphthalate, polyethylene terephthalate, polydimethylsiloxane, and polycarbonate.
3. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, The photosensitive semiconductor layer is made of photosensitive amorphous oxide semiconductor materials, including IGZO and InO. x ZnO x SnO x One of IZO, ZnSnO, nanowire IGZO and quantum dot modified IGZO.
4. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, The source and drain electrodes are made of one of the following materials: Al, ITO, Au, Cr-Au, and Ti-Au.
5. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, The material of the gate dielectric layer includes one or more of electrolyte solutions, ionic liquids, ionic gels, ion-conducting polymers, and proton-conducting polymers.
6. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, The structure of the friction layer is a planar structure, a pyramidal microstructure, or a cylindrical microstructure; The material of the friction layer is either a negative material or a positive material in the triboelectric electrode sequence; the negative material includes one of polytetrafluoroethylene, polypropylene, polyethylene, polydimethylsiloxane, and polyimide; the positive material includes one of nylon, silk, wool, and metal foil.
7. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, The elastic medium is made of one of the following materials: spring, rubber column, silicone microsphere, and elastic fiber, and is used to provide the restoring force required for the contact-separation motion between the friction layer and the gate dielectric layer.
8. The self-driven bionic vision-touch fusion sensor array according to claim 1, characterized in that, When the sensor array includes multiple sensing units, the sensing units are arranged in an M×N matrix on the flexible substrate, where M and N are both integers greater than or equal to 2.
9. A method for fabricating a self-driven bionic vision-touch fusion sensor array, characterized in that, The fabrication method for the self-driven bionic vision-touch fusion sensor array applicable to claims 1-8 includes: A photosensitive semiconductor layer is formed on the surface of the first flexible substrate; A source electrode and a drain electrode are formed on the photosensitive semiconductor layer; A gate dielectric layer is fabricated on the source electrode, the drain electrode, and the photosensitive semiconductor layer, and the gate dielectric layer also serves as the charge storage layer of the triboelectric nanogenerator; wherein, the gate dielectric layer forms an electric double layer under external stimulation to generate a tactile stimulation response, and the photosensitive semiconductor layer generates photogenerated carriers regulated by the electric double layer under light stimulation to increase the synaptic current; A friction layer is formed on the surface of the second flexible substrate; The friction layer is supported above the gate dielectric layer by an elastic medium, and the friction layer and the gate dielectric layer are spaced apart and opposite each other.
10. The method for fabricating a self-driven bionic vision-touch fusion sensor array according to claim 9, characterized in that, The photosensitive semiconductor layer is prepared by radio frequency magnetron sputtering with a sputtering power of 80-120W and a working pressure of 0.3-0.6Pa; the source electrode and the drain electrode are prepared by radio frequency magnetron sputtering with a sputtering power of 80-120W and a working pressure of 0.5-0.8Pa.