Touch positioning pressure sensing module and preparation method thereof

Abstract

The application belongs to the technical field of sensors, and particularly relates to a touch positioning pressure sensing module and a preparation method thereof. The sensing module comprises a top insulating packaging layer, an upper electrode, an insulating film layer, a mixed conductive layer and an input electrode which are stacked in sequence from top to bottom to form an upper integrated structure, wherein the input electrode is stacked at the lower right of the mixed conductive layer; a bottom insulating packaging layer and a bottom electrode are stacked from bottom to top to form a lower integrated structure; the upper integrated structure and the lower integrated structure are connected through first and second insulating spacers, and an intermediate gas cavity is formed by the first and second insulating spacers, the upper integrated structure and the lower integrated structure; the upper electrode, the input electrode and the bottom electrode are all connected with wires; the application avoids the problem of mutual interference of signals of general dual-mode sensors, and also avoids the complex process of needing a signal input decoupling algorithm model, thereby greatly reducing the back-end data processing task.

Description

Technical Field

[0001] This invention belongs to the field of sensor technology, specifically relating to a touch positioning pressure sensing module and its preparation method. Background Technology

[0002] With the collaborative efforts of electronic science, materials science, and computer science, biomimetic skin sensors have received widespread attention and achieved rapid development. By converting sensory information such as pressure or position into electrical signals, they reproduce, to some extent, the skin's ability to perceive external stimuli. Pressure and position signals are also two commonly used signals in human-computer interaction and intelligent control. Pressure sensors are commonly used to measure pressure, while touch sensors can be used to sense position. Both can provide good data when used individually, but simultaneously measuring both sets of data is more difficult. Currently, the main methods for simultaneously acquiring pressure magnitude and position information include: rapid scanning of pressure signals at different intersection points using matrix circuits, tactile array sensors, and hybrid sensors. However, these dual-modal sensor design methods employ multiple sensing technologies, requiring more complex design and manufacturing processes. This not only increases the development cycle but may also lead to a higher error rate during manufacturing. Furthermore, different types of sensing technologies may have different sensitivities to the environment, such as magnetic fields, electric fields, and temperature. These factors can cause signal interference and noise problems, affecting the accuracy and stability of measurements. In addition, in order to effectively integrate data from different sensing technologies, hybrid sensors require complex algorithms to process and parse the data, which may increase the computational load of the system and require stronger processor performance.

[0003] In summary, how to effectively acquire two high-precision sensing signals simultaneously, simplify the structure of a dual-modal sensor for pressure and position information, and avoid the complex process of data processing and parsing requiring algorithms, in order to meet richer and more multi-dimensional human-computer interaction needs, is an important problem that the development of flexible sensors urgently needs to solve. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a touch positioning pressure sensing module and its fabrication method. The sensing module includes: a top insulating encapsulation layer, an upper electrode, an insulating thin film layer, a hybrid conductive layer, a first insulating pad, a second insulating pad, a bottom electrode, a bottom insulating encapsulation layer, and an input electrode. The top insulating encapsulation layer, upper electrode, insulating thin film layer, hybrid conductive layer, and input electrode are stacked sequentially from top to bottom to form an upper integrated structure, wherein the input electrode is stacked to the lower right of the hybrid conductive layer. The bottom insulating encapsulation layer and bottom electrode are stacked from bottom to top to form a lower integrated structure. The upper and lower integrated structures are connected by the first and second insulating pads, and an intermediate gas cavity is formed by the first and second insulating pads, the upper integrated structure, and the lower integrated structure. The upper electrode, input electrode, and bottom electrode are all connected by wires.

[0005] Preferably, the intermediate gas cavity is filled with an inert gas, which is one of nitrogen, helium, argon, neon, xenon, or krypton.

[0006] Preferably, the hybrid conductive layer is composed of a polymer matrix and a high-dielectric filler material; the polymer matrix is ​​one or more of polydimethylsiloxane, polyethylene terephthalate, polytetrafluoroethylene, polyimide, silicone, and BASF copolyester; the high-dielectric filler material is one or more of graphene, carbon nanotubes, conductive carbon black, metal nanoparticles, and metal nanowires.

[0007] Furthermore, the mass fraction of high dielectric filler material in the hybrid conductive layer ranges from 2.14% to 6.27%.

[0008] Preferably, the ratio of the thickness of the mixed conductive layer to the thickness of the first insulating pad is in the range of 1:1 to 1:3.

[0009] The preferred materials for the top insulating encapsulation layer, the insulating film layer, and the bottom insulating encapsulation layer are one or more of polydimethylsiloxane, polyimide, parylene, polyurethane, epoxy resin, and polyester.

[0010] A method for manufacturing a touch positioning pressure sensing module, characterized in that it includes:

[0011] S1: The high dielectric filler material and the polymer matrix are mixed by stirring at a mass fraction of 2.14% to 6.27% to obtain a conductive mixture;

[0012] S2: Use a laser cutter to cut the polyethylene phthalate film to obtain a top insulating encapsulation layer, an insulating film layer, and a bottom insulating encapsulation layer; provide one or more filling holes in the top encapsulation layer;

[0013] S3: Clean the top insulating encapsulation layer, the insulating film layer and the bottom insulating encapsulation layer, and plate the upper electrode and the bottom electrode on the lower surface of the top insulating encapsulation layer and the upper surface of the bottom insulating encapsulation layer respectively.

[0014] S4: The top insulating encapsulation layer, insulating film layer, conductive mixture and copper sheet plated with the upper electrode are stacked from top to bottom to form an integrated upper structure;

[0015] S5: The bottom insulating encapsulation layer plated with the bottom electrode is used as the lower integrated structure, and the first insulating pad and the second insulating pad are bonded between the upper integrated structure and the lower integrated structure using an adhesive to form an intermediate gas cavity in the middle.

[0016] S6: Use conductive silver paste to connect wires to the right end of the input electrode, the top of the upper electrode, and the bottom of the bottom electrode, respectively.

[0017] S7: Place the device obtained in step S6 into a vacuum chamber, extract the air from the intermediate gas cavity through the filling hole; inject inert gas into the intermediate gas cavity through the filling hole and quickly seal the filling port to obtain the prepared touch positioning pressure sensing module.

[0018] Furthermore, in step S4, the process of forming the upper-layer integrated structure includes:

[0019] S41: After aligning the insulating film layer with the top insulating encapsulation layer plated with the upper electrode, heat and pressurize it through a hot press laminator to firmly bond them together; the lamination temperature is set at 100-150℃ and the pressure is 1-5Mpa;

[0020] S42: The conductive mixture is uniformly coated on the surface of the device obtained in step S41, and the ratio of its thickness to the first insulating pad is controlled to be within the range of 1:1 to 1:3.

[0021] S43: Place the device obtained in step S42 into an oven for processing. The oven temperature is 45 degrees Celsius and the processing time is 70 minutes.

[0022] S44: Use conductive silver paste to attach a copper sheet of the same size as the second insulating pad to the lower right side of the device obtained in step S43 to obtain an integrated upper structure.

[0023] The beneficial effects of this invention are as follows: This invention greatly simplifies the structure and manufacturing process of traditional dual-modal sensors, shortens the manufacturing cycle, and reduces manufacturing costs; the hybrid conductive layer in this invention is a mixture of a polymer substrate and a high-dielectric filler material, which maintains both the sensitivity of the capacitive pressure sensing module and good conductivity, enabling the sensor to simultaneously measure pressure and position; the thickness of the hybrid conductive layer improves the overall stability of the sensor while also considering the detection lower limit of the touch positioning module; this invention uses one conductive dielectric layer and three electrodes to simultaneously detect both pressure and position signals, and pressure and position are respectively detected using capacitive and resistive pressure sensing principles, acquiring changes in capacitance and resistance values, avoiding the problem of mutual interference between signals in general dual-modal sensors, and also avoiding the complex process of requiring signal input decoupling algorithm models, greatly reducing backend data processing tasks; this invention has broad application prospects in fields such as electronic skin, human-computer interaction, feature characterization, and decision support. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the touch positioning pressure sensing module structure in this invention;

[0025] Figure 2 This is a schematic diagram of the signal detection circuit of the touch positioning pressure sensing module in this invention;

[0026] Figure 3 This is a schematic diagram illustrating the principle of pressure sensing at the same location by the touch positioning pressure sensing module in this invention.

[0027] Figure 4 This is a schematic diagram illustrating the principle of sensing positioning information at different positions under the same pressure in the touch positioning pressure sensing module of this invention.

[0028] In the figure: 1. Top insulating encapsulation layer; 2. Upper electrode; 3. Insulating film layer; 4. Hybrid conductive layer; 5. First insulating pad; 6. Bottom electrode; 7. Bottom insulating encapsulation layer; 8. Input electrode; 9. Second insulating pad; 10. Middle gas cavity. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] This invention proposes a touch positioning pressure sensing module and its manufacturing method, such as... Figure 1As shown, the sensing module includes: a top insulating encapsulation layer 1, an upper electrode 2, an insulating thin film layer 3, a hybrid conductive layer 4, a first insulating pad 5, a second insulating pad 9, a bottom electrode 6, a bottom insulating encapsulation layer 7, and an input electrode 8; the top insulating encapsulation layer 1, the upper electrode 2, the insulating thin film layer 3, the hybrid conductive layer 4, and the input electrode 8 are stacked sequentially from top to bottom to form an integrated upper structure; specifically, in the integrated upper structure, the upper electrode 2 is attached to the lower surface of the top insulating encapsulation layer 1, the insulating thin film layer 3 is attached to the lower surface of the upper electrode 2, the hybrid conductive layer 4 is coated on the lower surface of the insulating thin film 3, and the input electrode 8 is attached to the right side of the lower surface of the hybrid conductive layer 4.

[0031] The bottom insulating encapsulation layer 7 and the bottom electrode 6 are stacked from bottom to top to form a lower integrated structure; that is, in the lower integrated structure, the bottom electrode 6 is attached to the upper surface of the bottom insulating encapsulation layer 7.

[0032] The upper integrated structure and the lower integrated structure are connected by a first insulating pad 5 and a second insulating pad 9. Specifically, the first insulating pad 5 and the second insulating pad 9 are respectively attached to the left and right sides of the bottom electrode 6, and the upper integrated structure is attached to the first insulating pad 5 and the second insulating pad 9; and the first insulating pad 5, the second insulating pad 9, the upper integrated structure and the lower integrated structure form an intermediate gas cavity 10; the upper electrode 2, the input electrode 8 and the bottom electrode 6 are all connected to wires (21, 81, 61).

[0033] In the touch positioning pressure sensing module of the present invention, the upper electrode 2 and the bottom electrode 6 constitute the parallel electrode plate of the capacitive pressure sensing module; the insulating thin film layer 3, the mixed conductive layer 4, the insulating gaskets 5 and 9, and the intermediate gas cavity 10, stacked sequentially, together constitute the capacitor medium of the capacitive pressure sensing module. The parallel electrode plate, the capacitor medium, and the wires 21 and 61 together constitute the capacitive pressure sensing module. The input electrode 8, the bottom electrode 6, the mixed conductive layer 4, and the wires 81 and 61 together constitute the touch positioning sensing module. When the mixed conductive layer 4 or the bottom electrode 6 is subjected to pressure, the mixed conductive layer 4 at the pressure point passes through the intermediate gas cavity 10 and makes contact with the bottom electrode 6, forming a conductive path between the input electrode 8 and the bottom electrode 6, realizing the function of simultaneously measuring position and pressure. Therefore, the mixed conductive layer 4 is both the capacitor medium material and the high-resistance layer of the touch positioning module. The bottom electrode 6 is both the bottom electrode plate of the capacitive pressure sensing module and the low-resistance layer and output electrode of the touch positioning module.

[0034] In some preferred embodiments, the intermediate gas cavity 10 is filled with an inert gas, which is one of nitrogen (N2), helium (He), argon (Ar), neon (Ne), xenon (Xe), or krypton (Kr). Filling the gas cavity with an inert gas in this invention can effectively improve the stability of the sensor module, extend the sensor's lifespan, and improve its accuracy. The inert gas is chemically very stable and will not chemically react with the materials inside the sensor, thus preventing oxidation or corrosion of the internal components and extending the sensor's lifespan. Furthermore, the inert gas has a stable and low dielectric constant; when pressure changes, the change in capacitance is mainly caused by physical changes in the sensor structure, rather than by changes in the gas properties, thereby improving the sensor's accuracy.

[0035] In some preferred embodiments, the hybrid conductive layer is composed of a polymer matrix and a high-dielectric filler material; wherein the polymer matrix is ​​one or more of polydimethylsiloxane (PDMS), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyimide (PI), silicone rubber, and BASF copolyester Ecoflex; and the high-dielectric filler material is one or more of graphene, carbon nanotubes, conductive carbon black, metal nanoparticles, and metal nanowires; in this invention, the preferred material for the hybrid conductive layer is a mixture of polydimethylsiloxane (PDMS) and carbon nanotubes (CNTs).

[0036] In some preferred embodiments, the mass fraction of high-dielectric filler material in the hybrid conductive layer ranges from 2.14% to 6.27%. When too little high-dielectric material is added, the conductive material per unit area is relatively small, resulting in fewer interconnected particles and incomplete conductive pathways. This leads to low conductivity in the composite material, affecting the touch positioning module's functionality. As the conductive material content increases, the spacing between conductive particles decreases. When the spacing decreases to a certain extent, electron tunneling occurs between the conductive material particles, achieving conductivity and exhibiting semiconductor properties, thus simultaneously fulfilling both conductive and capacitive dielectric functions. However, when too much conductive material is added, on the one hand, further increases in high-dielectric material content lead to uneven dispersion due to agglomeration in the matrix, causing a decrease in the composite material's conductivity. On the other hand, while the contact connections between conductive particles are conductive, the lack of capacitive characteristics between particles reduces the capacitance value. Therefore, high concentrations of conductive material decrease the capacitance sensitivity factor, affecting the capacitive pressure sensing module's functionality. Therefore, when the mass fraction of high dielectric material (the mass percentage of high dielectric constant material in polymer material) is in the range of 2.14% to 6.27%, the sensitivity of the capacitive pressure sensing module can be maintained while maintaining good conductivity, enabling the sensor to simultaneously measure the position of pressure.

[0037] A thinner dielectric layer and a thicker gas layer (e.g., a ratio of 1:4 to 1:5) can increase the capacitance change rate, thereby increasing sensitivity and response speed. However, a thicker gas layer can prevent the hybrid conductive layer 4 from forming a conductive path with the bottom electrode 6 under slight pressure, thus lowering the detection limit of the touch positioning module. A relatively thicker dielectric layer (e.g., a ratio of 1:1 to 1:3) can improve the overall stability of the sensor while maintaining the detection limit of the touch positioning module. In some preferred embodiments, the ratio of the thickness of the hybrid conductive layer to the thickness of the first insulating pad ranges from 1:1 to 1:3.

[0038] In some preferred embodiments, the materials of the top insulating encapsulation layer, the insulating film layer, and the bottom insulating encapsulation layer are one or more of the following electrical insulating materials: polydimethylsiloxane (PDMS), polyimide (PI), parylene (Parylene), polyurethane (PU), epoxy resin, and polyester (PET).

[0039] Compared to existing dual-modal sensors, the sensing module of this invention employs a structural design that shares a single functional layer 4 (hybrid conductive layer) and a bottom electrode 6 connected by three wires to achieve force and position sensing. This sensing module is based on an improved design of a capacitive pressure sensor. The hybrid conductive layer 4 serves as both a capacitor dielectric material layer and a high-resistivity material for the touch positioning module. The bottom electrode 6 acts as both the bottom electrode plate of the capacitive pressure sensing module and the low-resistivity material and output electrode of the touch positioning module. On one hand, this design greatly simplifies the structure and manufacturing process of traditional dual-modal sensors, shortens the manufacturing cycle, and reduces manufacturing costs. On the other hand, traditional touch positioning sensors typically require M×N×2 electrodes (M and N being the number of latitude and longitude lines at the touch point), which leads to highly complex signal transmission and processing, failing to meet the demands of complex signal processing such as multi-touch. While some progress has been made in touch positioning sensors, through structural design, the number of electrodes can be reduced to M×N+1 or M+N, shortening measurement time and simplifying signal processing. However, these touch positioning sensors are either unstable and susceptible to signal interference or have complex structures and a large number of electrodes. The touch positioning pressure sensing module of the present invention uses a conductive dielectric layer and three electrodes to simultaneously detect two signals: pressure and position information. The pressure and position are respectively based on capacitive and resistive pressure sensing principles, which reduces coupling interference and avoids complex decoupling processes.

[0040] This invention also provides a method for manufacturing a touch positioning pressure sensing module, comprising:

[0041] S1: Mix the high dielectric filler material with the polymer matrix at a mass fraction of 2.14% to 6.27% to obtain a conductive mixture.

[0042] 0.2g of carbon nanotubes were dispersed in 40ml of organic solvent ethanol or DMF; the carbon nanotube dispersion was then ultrasonically treated with an ultrasonic cleaner to obtain a carbon nanotube dispersion.

[0043] Take 4.53g of polydimethylsiloxane and mix the carbon nanotube dispersion with the 4.53g of polydimethylsiloxane at room temperature using a magnetic stirrer for 20 minutes. Set the stirring speed to 300 RPM (300 revolutions per minute) to obtain the mixture.

[0044] S2: Use a laser cutter to cut the polyethylene phthalate film to obtain a top insulating encapsulation layer, an insulating film layer and a bottom insulating encapsulation layer; provide one or more filling holes in the top encapsulation layer.

[0045] A 0.2mm thick polyethylene phthalate film was cut into three rectangular strips with an aspect ratio of 64:9 using a laser cutting machine. One strip served as the top insulating encapsulation layer, and the other two strips served as the insulating film layer and the bottom insulating encapsulation layer. One or more filling holes were provided in the top encapsulation layer. The laser tube power was 8W and the cutting speed was 15mm / s.

[0046] S3: Clean the top insulating encapsulation layer, the insulating film layer and the bottom insulating encapsulation layer, and plate the upper electrode and the bottom electrode on the lower surface of the top insulating encapsulation layer and the upper surface of the bottom insulating encapsulation layer, respectively.

[0047] Thoroughly clean the surfaces of the three PET films obtained in step S2 using an ultrasonic cleaner with diluted propanol (mix 20 ml of 70% propanol with deionized water at a volume ratio of 1:4). Ensure that oil, dust, and other contaminants are removed from the surfaces.

[0048] Two clean PET films, namely the top insulating encapsulation layer and the bottom insulating encapsulation layer, are placed on the sample stage of the sputtering equipment. A metal target is installed, with the distance between the target and the PET film set to 10-15 cm. The target is cleaned and pre-treated to remove any contaminants that may be present on its surface. The sputtering equipment is then turned on for sputtering. The vacuum level during sputtering is set to 10^-6 to 10^-8 Torr, and argon (Ar) is used as the sputtering gas. The argon flow rate is set to 20-50 sccm (standard cubic centimeters per minute). The sputtering power is typically set between 50-300 W, and the power density is set within the range of 1-3 W / cm². The sputtering time is 5-20 minutes. After sputtering, the sample is cooled in a vacuum environment to obtain a top insulating encapsulation layer 1 (with the upper electrode 2 deposited) and a lower integrated structure (insulating layer 7 with the bottom electrode 6 deposited).

[0049] S4: The top insulating encapsulation layer, insulating film layer, conductive mixture and copper sheet plated with the upper electrode are stacked from top to bottom to form an integrated upper structure.

[0050] S41: After aligning the insulating film layer with the top insulating encapsulation layer plated with the upper electrode, heat and pressurize it through a hot press laminator to firmly bond them together; the lamination temperature is set at 100-150℃ and the pressure is 1-5Mpa.

[0051] S42: Uniformly coat the conductive mixture onto the surface of the device obtained in step S41, controlling the ratio of its thickness to the first insulating pad to be within the range of 1:1 to 1:3.

[0052] The mixture is shaped as required and its thickness is in the ratio of 1:1 to 1:3 to that of the first insulating pad.

[0053] S43: Place the device obtained in step S42 into an oven for processing. The oven temperature is 45 degrees Celsius, and the processing time is 70 minutes.

[0054] S44: Use conductive silver paste to attach a copper sheet of the same size as the second insulating pad to the lower right side of the device obtained in step S43 to obtain an integrated upper structure.

[0055] After the adhesive is applied, the sample is cured in the environment to obtain the upper integrated structure.

[0056] S5: The bottom insulating encapsulation layer plated with the bottom electrode is used as the lower integrated structure, and the first insulating gasket and the second insulating gasket are bonded between the upper integrated structure and the lower integrated structure using an adhesive, forming an intermediate gas cavity. The insulating gasket is one of polytetrafluoroethylene (PET), polyimide (Kapton), polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET).

[0057] On the side of the lower integrated structure with a metal film deposited on its surface, 2mm from the port on both sides, insulating pads 5 and 9 are adhered using an adhesive (one of epoxy resin, acrylic, silicone rubber, or thermally conductive adhesive). The sum of the thicknesses of insulating pad 5 and the input electrode is equal to the thickness of insulating pad 9. Preferably, insulating pad 5 is 2mm long, 3mm wide, and 4mm thick, while insulating pad 9 is 2mm long, 3mm wide, and 3.9mm thick. The side of the upper integrated structure with the mixed conductive layer 4 is aligned and placed on the lower integrated structure with insulating pads 5 and 9 adhered on both sides. After pressing and adhering, a central gas cavity is formed.

[0058] S6: Use conductive silver paste to connect wires to the right end of the input electrode, the top of the upper electrode, and the bottom of the bottom electrode.

[0059] Conductive silver paste is used to lead out wire 81 from the right end of input electrode 8. Conductive silver paste is used to lead out wires 21 and 61 from the top of upper electrode and the bottom right end of bottom electrode.

[0060] S7: Place the device obtained in step S6 into a vacuum chamber, and extract the air from the intermediate gas cavity through the filling hole set in step S2; inject inert gas into the intermediate gas cavity through the filling hole and quickly seal the filling port to obtain the prepared touch positioning pressure sensing module.

[0061] After filling the intermediate gas cavity with inert gas, a flexible touch positioning pressure sensing module is obtained that simultaneously detects pressure magnitude and position information. The inert gas is one of nitrogen, helium, argon, neon, xenon, or krypton.

[0062] When using the touch positioning pressure sensing module designed in this invention, the touch positioning pressure sensing module is connected to the detection circuit; for example... Figure 2 As shown, the detection circuit includes a touch positioning pressure sensing module, a capacitance-to-digital converter (CDC) 401, a resistance detection module 402, and a constant voltage source 403. Input electrodes 2 and 8 of the sensing module are connected to the constant voltage source 403, and output electrode 6 is connected to the capacitance-to-digital converter (CDC) 401 and the resistance detection module 402. Simultaneously, the capacitance-to-digital converter (CDC) 401 and the resistance detection module 402 are connected to the constant voltage source.

[0063] The touch positioning pressure sensing module is connected to a capacitive digital converter 401 (CDC) via upper / bottom electrodes. Figure 3 In the diagram, (a) shows a cross-sectional view of the touch positioning pressure sensing module under slight pressure, and (b) shows a cross-sectional view of the touch positioning pressure sensing module under greater pressure. When subjected to slight pressure at the same location, such as... Figure 3 As shown in (a), the intermediate gas cavity 10 is compressed, and the distance between the two parallel electrode plates of the upper electrode 2 and the bottom electrode 6 decreases; when the pressure is increased, as... Figure 3 As shown in (b), the dielectric layer 4 is further compressed, and the deformation increases, which increases the capacitance in the capacitive pressure sensing module.

[0064] Figure 4 In the diagram, (a)-(d) are cross-sectional views of the touch positioning pressure sensing module when pressed at different positions; when the same pressure is applied at different positions, such as Figure 4 (a) shows the sensor in a static state. When subjected to a certain pressure, such as Figure 4 (b) The integrated structure of the upper layer of the touch positioning pressure sensing module undergoes a certain deformation, forming an electrical contact structure between the conductive hybrid layer 4 and the bottom electrode 6. Current flows in from the input electrode 8 and passes through the output electrode layer 6 at the pressing point. When the pressing position changes, such as... Figure 4As shown in (b)-(d), the degree of deformation at the pressed position of the conductive hybrid layer 4 is basically the same, but the current in the circuit changes differently depending on the pressed position. The closer the pressed position is to the right electrode 8, the greater the current, and vice versa. This proves that it can sense and identify different positions.

[0065] In summary, the touch positioning pressure sensing module designed in this invention collects changes in capacitance and resistance values, avoiding the signal interference problems common in dual-modal sensors. It also avoids the complex process of requiring signal input decoupling algorithms, significantly reducing backend data processing tasks. Based on the fact that the sensor generates two conductive paths between each sensing layer under force, different pressure magnitudes and force application locations will change the electrical signal values ​​of these two paths. Analyzing the strength of these two electrical signal values ​​allows for accurate identification of pressure magnitude and force application location. This invention can be attached to human skin or any other surface to detect pressure stimulation at different locations on an object's surface. It can also be used in human-computer interaction scenarios, fully leveraging the advantages of two-dimensional signal synergy to provide rich interactive commands for the sensing target. This touch positioning pressure sensing module has wide applications in electronic skin, human-computer interaction, feature profiling, and decision support.

[0066] The above-described embodiments further illustrate the purpose, technical solution, and advantages of the present invention. It should be understood that the above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made to the present invention within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A touch positioning pressure sensing module, characterized in that, include: The structure includes a top insulating encapsulation layer, an upper electrode, an insulating thin film layer, a hybrid conductive layer, a first insulating pad, a second insulating pad, a bottom electrode, a bottom insulating encapsulation layer, and an input electrode. The top insulating encapsulation layer, upper electrode, insulating thin film layer, hybrid conductive layer and input electrode are stacked from top to bottom to form an integrated upper structure, wherein the input electrode is stacked on the lower right side of the hybrid conductive layer; the bottom insulating encapsulation layer and bottom electrode are stacked from bottom to top to form a integrated lower structure. The upper integrated structure and the lower integrated structure are connected by a first insulating pad and a second insulating pad, and an intermediate gas cavity is formed by the first insulating pad, the second insulating pad, the upper integrated structure and the lower integrated structure; the upper electrode, the input electrode and the bottom electrode are all connected by wires; The hybrid conductive layer is composed of a polymer matrix and a high-dielectric filler material, enabling it to maintain both the sensitivity of the capacitive pressure sensing module and good conductivity. The polymer matrix is ​​one or more of polydimethylsiloxane, polyethylene terephthalate, polytetrafluoroethylene, polyimide, silicone, and BASF copolyester. The high-dielectric filler material is one or more of graphene, carbon nanotubes, conductive carbon black, metal nanoparticles, and metal nanowires. The mass fraction of the high-dielectric filler material in the hybrid conductive layer is in the range of 2.14% to 6.27%. The ratio of the thickness of the hybrid conductive layer to the thickness of the first insulating pad is in the range of 1:1 to 1:

3.

2. The touch positioning pressure sensing module according to claim 1, characterized in that, The intermediate gas cavity is filled with an inert gas, which is one of nitrogen, helium, argon, neon, xenon, or krypton.

3. The touch positioning pressure sensing module according to claim 1, characterized in that, The materials of the top insulating encapsulation layer, the insulating film layer, and the bottom insulating encapsulation layer are one or more of polydimethylsiloxane, polyimide, parylene, polyurethane, epoxy resin, and polyester.

4. A method for manufacturing a touch positioning pressure sensing module, characterized in that, include: S1: A conductive mixture is obtained by mixing a high-dielectric filler material with a polymer matrix at a mass fraction of 2.14% to 6.27% for the high-dielectric filler material. The polymer matrix is ​​one or more of polydimethylsiloxane, polyethylene terephthalate, polytetrafluoroethylene, polyimide, silicone, and BASF copolyester. The high-dielectric filler material is one or more of graphene, carbon nanotubes, conductive carbon black, metal nanoparticles, and metal nanowires. The conductive mixture maintains both the sensitivity of the capacitive pressure sensing module and good conductivity. S2: Use a laser cutter to cut the polyethylene phthalate film to obtain a top insulating encapsulation layer, an insulating film layer, and a bottom insulating encapsulation layer; provide one or more filling holes in the top encapsulation layer; S3: Clean the top insulating encapsulation layer, the insulating film layer and the bottom insulating encapsulation layer, and plate the upper electrode and the bottom electrode on the lower surface of the top insulating encapsulation layer and the upper surface of the bottom insulating encapsulation layer respectively. S4: The top insulating encapsulation layer, insulating film layer, conductive mixture and copper sheet plated with the upper electrode are stacked from top to bottom to form an integrated upper structure; S5: The bottom insulating encapsulation layer plated with the bottom electrode is used as the lower integrated structure, and the first insulating pad and the second insulating pad are bonded between the upper integrated structure and the lower integrated structure using an adhesive to form an intermediate gas cavity in the middle. S6: Use conductive silver paste to connect wires to the right end of the input electrode, the top of the upper electrode, and the bottom of the bottom electrode, respectively. S7: Place the device obtained in step S6 into a vacuum chamber, extract the air from the intermediate gas cavity through the filling hole; inject inert gas into the intermediate gas cavity through the filling hole and quickly seal the filling port to obtain the prepared touch positioning pressure sensing module.

5. The method for preparing a touch positioning pressure sensing module according to claim 4, characterized in that, In step S4, the process of forming the upper integrated structure includes: S41: After aligning the insulating film layer with the top insulating encapsulation layer plated with the upper electrode, heat and pressurize it through a hot press laminator to firmly bond them together; the lamination temperature is set at 100-150°C and the pressure is 1-5 MPa; S42: The conductive mixture is uniformly coated on the surface of the device obtained in step S41, and the ratio of its thickness to the first insulating pad is controlled to be within the range of 1:1 to 1:

3. S43: Place the device obtained in step S42 into an oven for processing. The oven temperature is 45 degrees Celsius and the processing time is 70 minutes. S44: Use conductive silver paste to attach a copper sheet of the same size as the second insulating pad to the lower right side of the device obtained in step S43 to obtain an integrated upper structure.

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