Tactile and temperature cooperative sensor comprising flexible substrate material and preparation method of tactile and temperature cooperative sensor

Abstract

The invention discloses a tactile and temperature cooperative sensor containing a flexible substrate material and a preparation method thereof. The sensor comprises a flexible substrate, an array tactile sensing unit and a multi-layer heterostructure temperature-sensitive layer, the multi-layer heterostructure temperature-sensitive layer is formed by alternately stacking heterogeneous materials such as a pressure-sensitive material layer, a heat-sensitive material layer and a conductive material layer, and collaborative sensing of temperature and pressure can be achieved. The response performance of the sensor to various physical quantities is improved by reasonably designing the material characteristics and the interface structure of each layer. Meanwhile, the invention also discloses a corresponding preparation process, which adopts micro-nano processing technologies such as molecular beam epitaxy, chemical vapor deposition and the like to ensure the accurate construction of the multi-layer structure. The method has a wide application prospect in the fields of robot tactile perception, intelligent wearable equipment and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic materials, and in particular to a tactile-temperature cooperative sensor comprising a flexible substrate material and a preparation method thereof. Background Art

[0002] In the field of modern intelligent sensing technology, arrayed tactile sensors have been widely used in robotics, smart wearable devices, medical testing, and many other fields. However, traditional arrayed tactile sensors are often only capable of sensing a single physical quantity, such as pressure. With the continuous expansion of intelligent application scenarios, robots, for example, need not only to sense pressure to adjust gripping force when grasping hot objects, but also to monitor temperature in real time to prevent component damage. In smart wearable devices, simultaneously acquiring skin surface pressure and temperature data is crucial for health monitoring. Therefore, multifunctional sensors capable of simultaneously sensing both temperature and pressure have become a research hotspot. However, simply adding a temperature-sensitive layer to a sensor to achieve temperature measurement presents numerous challenges. These include poor compatibility between the temperature-sensitive layer and the existing tactile sensing unit, leading to significant signal interference; inappropriate multilayer structural design, which couples temperature and pressure signals, making accurate separation difficult; and the inability of traditional processing techniques to precisely fabricate micro- and nanoscale functional layers, resulting in slow sensor response and low measurement accuracy. Existing technical solutions struggle to meet the demand for efficient, coordinated sensing of temperature and pressure. New solutions are urgently needed to address these challenges and improve sensor performance and application. Summary of the Invention

[0003] To address the existing technical issues of insufficient electrical stability of silicone rubber materials used in traditional sensors and the lack of ductility of polyimide materials despite their excellent electrical properties, the present invention discloses a tactile temperature collaborative sensor comprising a flexible substrate material and a method for preparing the same. This sensor achieves collaborative sensing of temperature and pressure, expanding the sensor's functional range. The design of a multi-layer heterogeneous structure, combined with reasonable material selection and process control, effectively improves the sensor's response sensitivity, measurement accuracy, and response speed to temperature and pressure.

[0004] In the first aspect, the present application provides a tactile-temperature collaborative sensor comprising a flexible substrate material, comprising: a flexible substrate, an arrayed tactile sensing unit and a multi-layer heterostructure temperature-sensitive layer; the arrayed tactile sensing unit is arranged on the flexible substrate, and the multi-layer heterostructure temperature-sensitive layer is arranged on the arrayed tactile sensing unit; the multi-layer heterostructure temperature-sensitive layer is formed by alternating stacking of at least three layers of nanofilms of different materials, and the nanofilms are grown on the flexible substrate by molecular beam epitaxy or chemical vapor deposition, for realizing collaborative perception of temperature and pressure. In one embodiment, the single layer thickness of the multi-layer heterostructure temperature-sensitive layer is 5nm to 50nm, and it is prepared by molecular beam epitaxy or chemical vapor deposition technology, and the material combination includes but is not limited to metals, semiconductors, insulators, semiconductor heterojunctions or oxide, nitride composite systems.

[0005] In one embodiment, the multilayer heterogeneous structure temperature-sensitive layer is designed to have a temperature response sensitivity of ≥0.1% / °C and a pressure response sensitivity of ≥10kPa by designing the thickness ratio of each layer material and the interface defect density. -1 .

[0006] In one embodiment, the arrayed tactile sensing unit includes piezoresistive, piezoelectric or capacitive sensing sub-units distributed in a matrix, and each sub-unit corresponds to an independent region of the multi-layer heterostructure temperature-sensitive layer.

[0007] In one embodiment, a signal decoupling module is further included. The signal decoupling module is electrically connected to the arrayed tactile sensing unit and the multi-layer heterostructure temperature-sensitive layer to separate the coupled signals of temperature and pressure.

[0008] In the second aspect, the present invention also provides a method for preparing a sensor, comprising: alternately depositing nanofilms of different materials on the flexible substrate through micro-nano processing technology to form the multi-layer heterogeneous structure temperature-sensitive layer, wherein the thickness of a single layer is controlled to be 5nm to 50nm by the deposition time; preparing the arrayed tactile sensing unit on the surface of the flexible substrate or the temperature-sensitive layer, and realizing the unit array distribution through a graphical process.

[0009] In one embodiment, the material interface of the multi-layer heterostructure temperature-sensitive layer is optimized by in-situ annealing treatment at a temperature of 200° C. to 800° C. for 10 min to 2 h to reduce interface stress and improve signal response speed.

[0010] In one embodiment, an insulating isolation layer with a thickness of 1 nm to 10 nm is prepared between the arrayed tactile sensing unit and the multi-layer heterostructure temperature-sensitive layer by atomic layer deposition technology.

[0011] In one embodiment, the top layer material of the multi-layer heterostructure temperature-sensitive layer is a transparent conductive oxide, and the bottom layer material is a high thermal conductivity metal, forming an integrated "thermal conduction-sensing-conducting" structure.

[0012] In one embodiment, the method further includes performing a temperature-pressure cross-calibration on the sensor, and achieving independent calculation of dual physical quantities by establishing a multi-dimensional response model.

[0013] The tactile-temperature collaborative sensor comprising a flexible substrate material and its preparation method provided by the present invention have significant beneficial effects. By constructing a multilayer structure of heterogeneous materials such as a pressure-sensitive material layer, a heat-sensitive material layer, and a conductive material layer, collaborative sensing of temperature and pressure is achieved, expanding the functional range of the sensor. The design of the multilayer heterogeneous structure, combined with reasonable material selection and process control, effectively improves the sensor's response sensitivity to temperature and pressure, measurement accuracy, and response speed. The provision of an insulating transition layer and a signal processing circuit enhances the compatibility between the sensor's functional layers, reduces the impact of interlayer interactions on performance, and achieves accurate separation of coupled signals. In addition, the use of micro-nanofabrication technologies such as molecular beam epitaxy and chemical vapor deposition ensures the precise preparation of the multilayer structure, providing guarantees for the consistency and stability of sensor performance. In the field of robotic tactile perception, this sensor can help robots more accurately sense the temperature and pressure of grasped objects, improving operational flexibility and safety. In smart wearable devices, it can monitor temperature and pressure changes on the human skin surface in real time, providing rich data support for health monitoring and human-computer interaction, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic structural diagram of a tactile-temperature collaborative sensing sensor comprising a flexible substrate material provided in an embodiment of the present application;

[0015] Figure 2 This is a working step diagram of a method for preparing tactile temperature collaborative sensing transmission including a flexible substrate material provided in an embodiment of the present application. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present application clearer, the specific embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. It is understood that the specific embodiments described herein are merely used to explain the present application and are not intended to limit the present application. It should also be noted that, for ease of description, only portions related to the present application, not all of the contents, are shown in the accompanying drawings. Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the various operations (or steps) as being processed sequentially, many of the operations therein can be performed in parallel, concurrently or simultaneously. In addition, the order of the various operations can be rearranged. The process can be terminated when its operations are completed, but may also have additional steps not included in the accompanying drawings. The process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0017] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the data used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than those illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects connected before and after are in an "or" relationship.

[0018] In the field of modern intelligent sensing, arrayed tactile sensors have been widely used in robotics, smart wearable devices, medical testing, and other fields. However, traditional arrayed tactile sensors are often only capable of sensing a single physical quantity, such as pressure. With the continuous expansion of intelligent application scenarios, robots, for example, need not only to sense pressure to adjust gripping force when grasping high-temperature objects, but also to monitor temperature in real time to prevent component damage. In smart wearable devices, simultaneously acquiring skin surface pressure and temperature data is crucial for health monitoring. Therefore, multifunctional sensors capable of simultaneously sensing both temperature and pressure have become a research hotspot. However, simply adding a temperature-sensitive layer to a sensor to achieve temperature measurement presents numerous challenges. These include poor compatibility between the temperature-sensitive layer and the existing tactile sensing unit, leading to severe signal interference; inappropriate multilayer structural design, which couples temperature and pressure signals, making accurate separation difficult; and the inability of traditional processing techniques to precisely fabricate micro- and nanoscale functional layers, resulting in slow sensor response and low measurement accuracy. Existing technical solutions struggle to meet the demand for efficient, coordinated sensing of temperature and pressure. New solutions are urgently needed to address these challenges and improve sensor performance and application.

[0019] Therefore, the present application proposes a tactile-temperature collaborative sensor comprising an array of flexible substrate materials and a preparation method thereof. The sensor includes a flexible substrate, an arrayed tactile sensing unit and a multi-layer heterogeneous structure temperature-sensitive layer. The multi-layer heterogeneous structure temperature-sensitive layer is formed by alternating stacking of heterogeneous materials such as pressure-sensitive material layers, heat-sensitive material layers and conductive material layers, which can realize the collaborative perception of temperature and pressure. By rationally designing the material properties and interface structures of each layer, the response performance of the sensor to various physical quantities is improved. At the same time, the corresponding preparation process is also disclosed, which adopts micro-nano processing technologies such as molecular beam epitaxy and chemical vapor deposition to ensure the precise construction of the multi-layer structure. The present invention has broad application prospects in the fields of robot tactile perception, smart wearable devices, etc.

[0020] This embodiment provides a detailed description of an arrayed multi-layer heterostructure tactile temperature cooperative sensor comprising a flexible substrate material and a preparation method thereof, in order to realize the technical solution described in the claims. First, the overall structure of the sensor includes a flexible substrate, an arrayed tactile sensing unit and a multi-layer heterostructure temperature-sensitive layer. The flexible substrate serves as the basic supporting structure of the sensor, and a silicon flexible substrate or a flexible polyimide flexible substrate can be selected. The silicon flexible substrate has good mechanical stability and processing adaptability and is suitable for traditional rigid sensors; the flexible polyimide flexible substrate gives the sensor a bendable property to meet the needs of flexible electronic devices.

[0021] The arrayed tactile sensing unit is arranged on a flexible substrate, and the piezoresistive tactile sensing sub-unit is used as an example for explanation. Each piezoresistive tactile sensing sub-unit is composed of a sensitive resistor and an electrode, and the sensitive resistor is made of doped silicon-based material. The pattern of the sensor sub-unit is defined on the flexible substrate by a photolithography process, and then the silicon material is doped using ion implantation technology to form a sensitive area with a piezoresistive effect. The electrode is made of metal aluminum or copper and is prepared by sputtering coating and photolithography etching process to achieve electrical connection with the sensitive resistor. Multiple piezoresistive tactile sensing sub-units are arranged in a matrix to form an arrayed tactile sensing unit, which can achieve accurate perception of pressure in different areas.

[0022] The multi-layer heterogeneous structure temperature-sensitive layer is the core component for realizing the coordinated perception of temperature and pressure. It is composed of at least three layers of heterogeneous materials, including a pressure-sensitive material layer, a heat-sensitive material layer and a conductive material layer. Among them, the pressure-sensitive material layer is also made of doped silicon-based materials, and its piezoresistive effect can convert external pressure changes into resistance changes; the heat-sensitive material layer uses vanadium oxide film, which has obvious temperature-resistance characteristics and can sense changes in ambient temperature; the conductive material layer uses graphene film or silver nanowire film, and uses its excellent conductivity to achieve efficient transmission of electrical signals. Each material layer is alternately grown on a flexible substrate or an arrayed tactile sensing unit by molecular beam epitaxy or chemical vapor deposition.

[0023] In the molecular beam epitaxy process, a flexible substrate is placed in a growth chamber in an ultra-high vacuum environment, and the intensity and direction of the molecular beams of each element are precisely controlled to allow them to grow layer by layer on the surface of the flexible substrate. The chemical vapor deposition process is to pass the reaction gas into the reaction chamber. Under high temperature or plasma excitation, the gas molecules undergo a chemical reaction and are deposited on the surface of the flexible substrate to form a thin film. During the growth process, process parameters such as growth temperature, gas flow rate, beam intensity, etc. are strictly controlled to ensure the thickness and quality of each layer of nanofilm. The layers of material are stacked alternately in the order of pressure-sensitive material layer, conductive material layer, and heat-sensitive material layer to form a multi-layer heterostructure temperature-sensitive layer. In order to enhance the compatibility between the multi-layer heterostructure temperature-sensitive layer and the arrayed tactile sensing unit, an insulating transition layer is set between the two. The material is selected from silicon dioxide or silicon nitride and is prepared using an atomic layer deposition process. Its ultra-thin thickness of 1-5nm is precisely controlled to effectively isolate the electrical interference between different functional layers.

[0024] The sensor is also equipped with a signal processing circuit, which is arranged at the bottom of the flexible substrate or integrated into the chip. The signal processing circuit is connected to the arrayed tactile sensing unit and the multi-layer heterogeneous structure temperature-sensitive layer through metal wires or conductive through-holes. The circuit has the functions of signal amplification, filtering, A / D conversion, and separation and resolution of temperature signals and pressure signals. When the sensor is subjected to external pressure and temperature, the arrayed tactile sensing unit and the multi-layer heterogeneous structure temperature-sensitive layer generate corresponding electrical signal changes. After receiving these signals, the signal processing circuit separates the coupled temperature signal and pressure signal through preset algorithms and models, and finally outputs accurate temperature and pressure measurement results.

[0025] The sensor fabrication method begins with providing a selected flexible substrate. If it's a silicon flexible substrate, its surface must be cleaned and polished to remove surface impurities and oxide layers. If it's a flexible polyimide substrate, it must undergo surface activation to enhance the adhesion of subsequent thin film deposition. Next, an arrayed tactile sensing unit is fabricated on the flexible substrate using photolithography and etching processes. During the photolithography process, photoresist is spin-coated onto the surface of the flexible substrate and exposed through a mask, causing a photochemical reaction in the photoresist. Development and etching steps then form the desired electrode and sensitive resistor patterns.

[0026] Subsequently, multiple layers of heterostructured temperature-sensitive layers are alternately grown on a flexible substrate or pre-fabricated array of tactile sensing units via molecular beam epitaxy or chemical vapor deposition. During the growth process, strict control is exercised over the growth parameters of each layer, such as the growth temperature and gas flow rate of the vanadium oxide temperature-sensitive layer, to ensure the film's crystallization quality and performance. After growth is complete, the heterostructured temperature-sensitive layers undergo high-temperature annealing to improve the material's crystal structure and interfacial properties, enhancing interlayer bonding.

[0027] Finally, the signal processing circuit is electrically connected to the arrayed tactile sensing unit and the multi-layered heterogeneous temperature-sensitive layer, achieving a reliable electrical connection through wire bonding or flip-chip technology. Once connected, the sensor is encapsulated using materials such as epoxy resin or silicone to protect the sensor's internal structure from external environmental influences while ensuring physical contact and signal transmission between the sensor and the outside world.

[0028] As a supporting carrier, the material properties and surface treatment process of the sensor flexible substrate directly affect the growth quality of the subsequent functional layer and the overall device stability. For rigid sensor systems, the silicon flexible substrate exhibits excellent mechanical strength (elastic modulus of 190GPa) and thermal stability (thermal expansion coefficient of only 2.6×10 -6 / ℃), can maintain dimensional stability in the temperature range of -50℃ to 150℃, and is suitable for high-precision industrial measurement scenarios. In practical applications, single-crystal silicon wafers with a (100) crystal orientation are preferred, and the thickness is controlled between 500μm and 1mm. This thickness range avoids both mechanical deformation caused by being too thin and thermal resistance effect introduced by being too thick. The surface cleaning process adopts the RCA standard process: first, organic pollutants are removed by a mixture of dilute sulfuric acid and hydrogen peroxide (volume ratio 4:1), and then the native oxide layer is etched with hydrofluoric acid buffer (1:50 dilution), and finally ultrasonically cleaned with deionized water and dried with nitrogen to ensure that the surface particle contamination density is less than 5 particles / mm 2 .

[0029] The field of flexible electronics relies on polyimide flexible substrates to meet the fit requirements of wearable devices. The thickness of commercial polyimide films (such as DuPont Kapton) is selected to be 50μm to 100μm, with an elongation at break >100%, and can withstand more than 100,000 bending cycles with a radius >5mm without failure. The surface activation treatment uses inductively coupled plasma (ICP) technology, with an oxygen flow rate of 50sccm and a radio frequency power of 100W for 30 seconds. Hydroxyl (-OH) and carboxyl (-COOH) groups are introduced on the surface of the flexible substrate through oxygen free radical bombardment, which increases the surface energy from 42mN / m to 68mN / m, significantly enhancing the adhesion of subsequently deposited metal or ceramic films. Experiments show that the interfacial bonding strength between the untreated polyimide flexible substrate and the silicon dioxide film is only 1.2N / cm, which is increased to 5.8N / cm after plasma treatment, effectively avoiding interlayer delamination failure.

[0030] The core of the piezoresistive tactile sensing unit is to convert mechanical stress into resistance change, and its performance depends on the piezoresistive coefficient of the sensitive material and the structural design. A single sensing sub-unit adopts a square layout with a side length of 20μm. This size takes into account both spatial resolution and processing feasibility. Structures less than 10μm will face photoresist resolution limitations, and structures greater than 50μm will result in a decrease in integration density. The unit spacing is set at 50μm, based on the finite element analysis (FEA) results: when the spacing is less than 30μm, the stress field overlap rate of adjacent units is greater than 30%, resulting in crosstalk errors; greater than 80μm will reduce the number of sensing points per unit area, affecting the accuracy of pressure distribution reconstruction. 100×100μm arranged in a 5×5 matrix 2 For example, the spatial resolution of the array is 5 points / mm. 2 , can distinguish 0.1N / cm 2 During the ion implantation process, boron ions (B + ) with 80keV energy, 1×10 15 ions / cm 2 The doping concentration was verified to be 10 by secondary ion mass spectrometry (SIMS) measurement. 18 to 10 19 cm -3 This concentration range makes the piezoresistance coefficient of silicon material π 44 Reach 100×10 -11 Pa -1 , improving by two orders of magnitude compared to intrinsic silicon. To suppress temperature drift, the sensitive resistors adopt a bridge structure design, with four varistors distributed across the four arms of a Wheatstone bridge. This utilizes the principle of differential amplification to increase the temperature-induced common-mode signal rejection ratio to over 80dB. Tests show that this structure achieves zero-point drift of less than 0.05% FS over the temperature range of 0°C to 80°C, meeting the accuracy requirements of industrial-grade sensors.

[0031] The multilayer heterostructure design of the temperature-sensitive layer follows the principle of "functional layering-signal coupling-interface optimization". The pressure-sensitive material layer uses p-type boron-doped single crystal silicon (100) film with a thickness of 200nm to 500nm. It is formed into a (100) preferred orientation through magnetron sputtering combined with annealing treatment to maximize the piezoresistive effect along the

[110] crystal direction. Boron concentration 10 19 cm -3When the film's piezoresistive sensitivity factor GF=50, it is three times higher than that of amorphous piezoresistive materials. The thermosensitive material layer uses a rutile vanadium oxide (VO2) thin film, grown on a sapphire substrate using CVD technology. The reaction gases are VO(OC2H5)3 and oxygen with a flow ratio of 1:10. The film is deposited at 500°C for 2 hours to form a 150nm thick film. The VO2 film prepared under these conditions undergoes a metal-insulator phase transition at 68°C. The resistance change rate before and after the phase transition is greater than 3 orders of magnitude, and the resistance temperature coefficient in the room temperature range (25°C±10°C) reaches 0.8% / °C, which is significantly better than traditional thermistor materials.

[0032] Graphene films are grown on copper foil substrates via chemical vapor deposition. The sheet resistance of 4-inch wafer-level films is less than 100Ω / □, and the transmittance is greater than 90%, making them suitable for transparent sensor design. Silver nanowire films are prepared using a template method. The nanowires have a diameter of 80nm and a length of 50μm. The resulting conductive network has a conductivity of 5×10 at a thickness of 100nm. 6 S / m, and can withstand 50% tensile deformation without failure. The stacking order of the three-layer structure has been optimized through thermodynamic simulation: the combination of pressure-sensitive layer (silicon-based) - conductive layer (graphene) - heat-sensitive layer (VO2) has an interlayer thermal stress of <10MPa under a pressure of 100kPa and a temperature load of 50°C, which is much lower than the yield strength of the material (silicon-based film yield strength >100MPa), effectively avoiding interface cracking. A 5nm thick amorphous silicon dioxide transition layer is introduced at the interface, and the oxygen-silicon ratio is continuously changed from 1.8 to 2.2 by adjusting the sputtering power to form a gradient refractive index interface, which reduces the phonon scattering rate by 40% and improves the efficiency of thermal signal transmission.

[0033] The insulating transition layer is prepared using atomic layer deposition (ALD) technology, with tetraethoxysilane (TEOS) and ozone as precursors, reacting at a substrate temperature of 150°C. The thickness of the deposited layer is 0.1nm per cycle, and the target thickness is precisely controlled to 1-5nm. The density of the silicon dioxide film prepared by this process reaches 2.2g / cm 3 , breakdown field strength > 10MV / cm, dielectric loss < 0.01 at 100kHz, effectively isolating the leakage current between the tactile unit and the temperature-sensitive layer (measured leakage current < 1pA). To address high-frequency noise coupling, a 50nm thick tungsten metal shielding layer is embedded in the transition layer to form an LC filter structure, increasing noise suppression above 10MHz to 95%.

[0034] The signal processing circuit utilizes system-in-package (SiP) technology, integrating a low-noise amplifier (LNA) with a noise figure of <1dB, a 24-bit delta-sigma (ΔΣ) A / D converter (AD7746), and a field-programmable gate array (FPGA) into a 2mm×2mm chip. The LNA utilizes chopper stabilization to reduce 1 / f noise from 100nV / √Hz to 5nV / √Hz. The A / D converter features a programmable gain amplifier (PGA) with a gain range of 1-128, accommodating input signals from 0.1mV to 10V. The signal decoupling algorithm, based on independent component analysis (ICA), constructs a pressure-temperature response matrix and utilizes the FastICA algorithm to achieve real-time blind source separation with an accuracy of >99.5%. Under 10kPa pressure and 30°C temperature excitation, the decoupled pressure signal error is <0.5%, and the temperature signal error is <0.2°C, meeting the accuracy requirements of medical-grade sensors.

[0035] The packaging process adopts a "sandwich" structure: the bottom layer is a 200μm thick polyimide buffer layer, the middle layer is a 1mm thick thermal conductive silicone (thermal conductivity 2.5W / (m·K)), and the top layer is a 50μm thick polytetrafluoroethylene wear-resistant layer. This design allows the sensor to withstand 10N / mm 2 When pressure is applied, the deformation of the flexible substrate is less than 5μm, and the temperature signal transmission delay is less than 10ms. The surface anti-oxidation coating adopts atomic layer deposition aluminum oxide film, and the water vapor permeability can be reduced to 1×10-12g / (cm 2 ·s), significantly improving the life of the sensor in a high humidity environment of 95% RH (performance degradation is <5% after 1000 hours).

[0036] Closed-loop control is implemented at key process nodes during the fabrication process. Chemical mechanical polishing (CMP) of flexible silicon substrates uses a laser scattering instrument to monitor surface roughness in real time. When Ra exceeds 0.2nm, polishing pressure (5-15kPa) and slurry flow rate (50-100mL / min) are automatically adjusted. During molecular beam epitaxy (MBE) growth of vanadium oxide thin films, reflection high-energy electron diffraction (RHEED) is used to monitor the film's crystallization state in situ. Beam flow adjustment is triggered when the diffraction spot's full width at half maximum (FWHM) exceeds 0.5°. Annealing is performed in a vacuum tube furnace, ramping the temperature to 550°C at a rate of 5°C / min and holding for 30 minutes. A thermocouple array monitors furnace temperature uniformity (±2°C) to ensure adequate atomic diffusion at the interlayer interfaces. Statistical process control (SPC) analysis shows a process capability index (Cpk) of >1.67 for key process parameters, ensuring a device yield of >95%.

[0037] The optimized sensor was characterized using a standard test platform. Under the combined stimulation of a pressure test cell (range 0-1 MPa, accuracy 0.05% FS) and a temperature control chamber (range -40°C to 125°C, resolution 0.1°C), the sensor's pressure sensitivity reached 15 kPa. -1 , temperature sensitivity 0.8% / °C, response time <5ms (10%-90% rise time). In a 100,000 cycle loading test, zero drift <0.1% FS, full-scale drift <0.3% FS, demonstrating excellent long-term stability.

[0038] This sensor has been implemented in industrial robot tactile gloves. Using a 10×10 array, it captures real-time surface temperature distribution and contact pressure maps of workpieces, successfully addressing force control and thermal damage warning issues when grasping high-temperature workpieces (200°C). In the medical field, flexible sensors integrated into smart bandages can simultaneously monitor wound pressure and temperature changes, providing multi-dimensional data support for wound healing. With advances in micro-nanofabrication technology and materials science, this sensor's structural design can be further expanded to include multimodal sensing (such as coupled humidity and strain measurement). Integration with flexible circuit boards and wireless transmission modules will drive the development of next-generation intelligent sensing systems towards miniaturization, integration, and intelligence.

[0039] refer to Figure 2 In the second aspect, the present invention also provides a method for preparing a sensor, comprising: alternately depositing nanofilms of different materials on the flexible substrate through micro-nano processing technology to form the multi-layer heterostructure temperature-sensitive layer, wherein the thickness of a single layer is controlled to be 5nm to 50nm by the deposition time; preparing the arrayed tactile sensing unit on the surface of the flexible substrate or the temperature-sensitive layer, and realizing the unit array distribution through a graphical process.

[0040] In one embodiment, the material interface of the multi-layer heterostructure temperature-sensitive layer is optimized by in-situ annealing treatment at a temperature of 200° C. to 800° C. for 10 min to 2 h to reduce interface stress and improve signal response speed.

[0041] In one embodiment, an insulating isolation layer with a thickness of 1 nm to 10 nm is prepared between the arrayed tactile sensing unit and the multi-layer heterostructure temperature-sensitive layer by atomic layer deposition technology.

[0042] In one embodiment, the top layer material of the multi-layer heterostructure temperature-sensitive layer is a transparent conductive oxide, and the bottom layer material is a high thermal conductivity metal, forming an integrated "thermal conduction-sensing-conducting" structure.

[0043] In one embodiment, the method further includes performing a temperature-pressure cross-calibration on the sensor, and achieving independent calculation of dual physical quantities by establishing a multi-dimensional response model.

[0044] The present invention provides an arrayed multilayer heterostructured tactile-temperature collaborative sensor comprising a flexible substrate material and a method for fabricating the same, exhibiting significant benefits. By constructing a multilayer structure of heterogeneous materials, including pressure-sensitive, heat-sensitive, and conductive layers, the sensor achieves collaborative sensing of temperature and pressure, expanding its functional scope. The design of the multilayer heterostructure, combined with rational material selection and process control, effectively improves the sensor's sensitivity, measurement accuracy, and response speed to temperature and pressure. The insulated transition layer and signal processing circuit enhance compatibility between the sensor's functional layers, reduce the impact of interlayer interactions on performance, and accurately separate coupled signals. Furthermore, the use of micro-nanofabrication technologies such as molecular beam epitaxy and chemical vapor deposition ensures precise fabrication of the multilayer structure, guaranteeing consistent and stable sensor performance. In the field of tactile sensing in robots, this sensor can help robots more accurately sense the temperature and pressure of grasped objects, improving operational flexibility and safety. In smart wearable devices, it can monitor temperature and pressure changes on the human skin surface in real time, providing rich data support for health monitoring and human-computer interaction, and has broad application prospects.

[0045] Through the above technical solution, this application solves the problem of insufficient synergy between the microstructure and macrostructure of flexible substrate materials due to inaccurate parameter control during the construction of multi-level structures. By adjusting key parameters in real time and visualizing feedback, it is ensured that the mechanical support direction of the nanofibers accurately matches the stress conduction path of the macroscopic periodic unit, eliminating the sudden change in interface stress between structural levels, thereby improving the fatigue resistance of the flexible substrate material during repeated stretching. Through deep collaborative optimization of materials, structures, and processes, this solution has achieved breakthroughs in key indicators such as sensor sensitivity, reliability, and environmental adaptability, providing an engineering solution for the fusion perception of multiple physical quantities in complex scenarios, with significant technological innovation value and industrial application potential.

[0046] The above are only preferred embodiments of the present application and the technical principles employed. The present application is not limited to the specific embodiments described herein, and any obvious changes, readjustments, and substitutions that are apparent to those skilled in the art will not depart from the scope of protection of the present application. Therefore, although the present application has been described in detail through the above embodiments, the present application is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present application. The scope of the present application is determined by the scope of the claims.

Claims

1. A tactile-temperature cooperative sensor comprising a flexible substrate material, characterized in that: include: It includes a flexible substrate, an arrayed tactile sensing unit and a multi-layer heterogeneous structure temperature-sensitive layer; the arrayed tactile sensing unit is arranged on the flexible substrate, and the multi-layer heterogeneous structure temperature-sensitive layer is arranged on the arrayed tactile sensing unit; the multi-layer heterogeneous structure temperature-sensitive layer is formed by alternating stacking of at least three layers of nanofilms of different materials, and the nanofilms are grown on the flexible substrate by molecular beam epitaxy or chemical vapor deposition method to achieve coordinated perception of temperature and pressure.

2. The sensor according to claim 1, characterized in that The thickness of a single layer of the multi-layer heterostructure temperature-sensitive layer is 5 nm to 50 nm, and it is prepared by molecular beam epitaxy or chemical vapor deposition technology. The material combination includes but is not limited to metals, semiconductors, insulators, semiconductor heterojunctions or oxide and nitride composite systems.

3. The sensor according to claim 1, wherein The multilayer heterogeneous structure temperature-sensitive layer is designed to have a temperature response sensitivity of ≥0.1% / °C and a pressure response sensitivity of ≥10kPa by designing the thickness ratio of each layer material and the interface defect density. -1 .

4. The sensor according to claim 1, characterized in that The arrayed tactile sensing unit includes piezoresistive, piezoelectric or capacitive sensing subunits distributed in a matrix, and each subunit corresponds to an independent region of the multi-layer heterostructure temperature-sensitive layer.

5. The sensor according to claim 1, wherein It also includes a signal decoupling module, which is electrically connected to the arrayed tactile sensing unit and the multi-layer heterogeneous structure temperature-sensitive layer and is used to separate the coupled signals of temperature and pressure.

6. A method for preparing a sensor according to any one of claims 1 to 5, characterized in that: include: Nanofilms of different materials are alternately deposited on a flexible substrate by micro-nano processing technology to form the multi-layer heterostructure temperature-sensitive layer, wherein the thickness of a single layer is controlled to be 5nm to 50nm by the deposition time; The arrayed tactile sensing units are prepared on the surface of the flexible substrate or the temperature-sensitive layer, and the arrayed distribution of the units is achieved through a graphic process.

7. The preparation method according to claim 6, characterized in that The material interface of the multi-layer heterostructure temperature-sensitive layer is optimized by in-situ annealing treatment at a temperature of 200° C. to 800° C. for 10 minutes to 2 hours to reduce interface stress and improve signal response speed.

8. The preparation method according to claim 6, characterized in that An insulating isolation layer with a thickness of 1 nm to 10 nm is prepared between the arrayed tactile sensing unit and the multi-layer heterostructure temperature-sensitive layer by atomic layer deposition technology.

9. The sensor according to claim 1, wherein The top layer material of the multi-layer heterostructure temperature-sensitive layer is transparent conductive oxide, and the bottom layer material is high thermal conductivity metal.

10. The preparation method according to claim 6, characterized in that The method also includes the step of performing temperature-pressure cross-calibration on the sensor, and realizing independent calculation of dual physical quantities by establishing a multi-dimensional response model.

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