Shielding strip based flexible temperature and stress integrated sensor array and method of fabrication

Abstract

This invention discloses a flexible temperature and stress integrated sensor array based on shielded strips and its fabrication method, relating to the field of microelectronics technology. The array includes: a first conductive layer comprising multiple first conductive lines arranged parallel to a first direction; a second conductive layer comprising multiple second conductive lines arranged parallel to a second direction; the first and second conductive lines define multiple regions of the array, each region comprising four diagonally arranged sub-regions, each region housing two stress sensors and one temperature sensor; and a shielded strip layer located between the first and second conductive layers, comprising multiple shielded strips arranged parallel to the second direction, with the second conductive lines located on the upper surface of the shielded strips; wherein the first and second directions intersect. This invention significantly reduces the area ratio of conductive lines in traditional layouts, greatly improving the effective utilization rate of the sensing area.

Description

Technical Field

[0001] This invention belongs to the field of microelectronics technology, specifically relating to a flexible temperature and stress integrated sensor array based on shielded strips and its fabrication method. Background Technology

[0002] In recent years, with the development of microelectronics technology, flexible sensors with variable performance parameters have gradually entered the public eye. Flexible sensors currently have wide applications in fields such as intelligent robots, intelligent healthcare, smart transportation, new materials industries, and industrial production. Currently, single flexible stress, temperature, and humidity sensors are favored by many researchers and have been the subject of extensive research. Their principle typically involves converting changes in environmental physical quantities into changes in electrical signals such as resistance and capacitance within the sensor itself. Their manufacturing methods also vary, including screen printing, inkjet printing, and surface coating.

[0003] In existing technologies, researchers have developed a flexible temperature sensor based on cross-linked PEDOT:PSS. By introducing a cross-linking agent and a fluorinated polymer passivator (CYTOP), the prepared temperature sensor exhibits excellent stability in environments with 30–80% relative humidity (RH), and a temperature sensitivity coefficient as high as -0.77% / K within the range of 25–50°C. Other researchers have used reduced graphene oxide (r-GO), single-walled carbon nanotubes (SWCNTs), and multi-walled carbon nanotubes (MWCNTs) as sensing materials to fabricate temperature-sensitive units on PET substrates via spraying. Their test results show that r-GO exhibits the best temperature-sensitive properties, possessing a negative temperature coefficient of resistance (TCT) of 6.345 × 10⁻⁶. -3The response time can reach 1.2s at ℃, but the accuracy of this type of temperature sensor is not high. Other researchers, addressing the difficulty of simultaneously achieving high temperature and transient response in temperature sensors, proposed a flexible sensing array based on an ultrathin molybdenum-tungsten-sulfur alloy film. The fabricated flexible temperature sensor can achieve transient temperature response over an ultra-wide temperature range (-253~800℃), but its accuracy in high-temperature environments is poor, and it can only monitor temperature-related physical quantities. Still other researchers have prepared conductive composite inks using CNTs and polydimethylsiloxane, and fabricated flexible strain sensors using multi-walled carbon nanotubes / polydimethylsiloxane (MWCNT / PDMS) via screen printing. These sensors achieve a working range of 100%, but the sensitivity (GF) is only 1.55. Other researchers have used screen printing technology to fabricate LIG flexible strain sensors on PDMS flexible substrates using laser-induced graphene (LIG). These sensors exhibit a sensitivity of 96% within a strain range of 0–13%. Performance testing revealed good IV characteristics, a stable step response, fast response speed (approximately 0.24 s) and recovery speed (approximately 0.25 s), and good durability (over 1000 cycles). However, the manufacturing process is complex and costly. Regarding sensor array integration, some researchers have used direct-write printing technology to create a 4×4 strain sensor array. This array has a sensitivity coefficient of 14.5 and can monitor strain in the range of 0–1.5%. Although it integrates the sensor array, this type of array has a relatively small sensitivity coefficient and strain monitoring range, and can only monitor strain physical quantities.

[0004] In the field of flexible sensing, sensor manufacturing methods mainly include direct-write printing, inkjet printing, and screen printing. While inkjet printing and direct-write printing, as high-precision additive manufacturing technologies, demonstrate advantages in sensor customization and complex structure fabrication, their practical applications still face constraints related to cost, efficiency, and materials. From a cost perspective, inkjet printing and direct-write printing rely on expensive precision printing equipment, the price of which directly determines the final sensor's quality. In terms of efficiency, printing is typically based on a point-by-point deposition process, resulting in relatively slow printing speeds. Especially when fabricating large-area sensor arrays, the coverage area of ​​a single print is limited, often requiring multiple stitching or repeated scanning, which not only reduces overall production efficiency but may also introduce performance inhomogeneities due to alignment deviations. Regarding materials, printing inks must possess strict rheological properties (such as appropriate viscosity and surface tension) to ensure stable printing and forming, which greatly limits the range of usable materials and makes it difficult for many high-performance sensitive materials to be adapted to the printing process. Therefore, although these technologies are suitable for research and development and small-batch production, their cost and material bottlenecks still hinder their widespread adoption in large-scale sensor manufacturing.

[0005] Compared to traditional printing, screen printing offers advantages in terms of manufacturing cost, efficiency, and materials. However, traditional screen printing for sensor fabrication faces two main challenges. First, when integrating high-density sensor arrays, screen printing suffers from structural limitations such as difficulty in separating row and column wires, challenges in multi-layer printing, and low effective area utilization. Screen-printed sensor arrays are planar, and to avoid wire crossings, the wires leading out from both ends of the sensor are often located on the same layer. Furthermore, the wires themselves do not possess sensing functionality but require a large substrate area to ensure conductivity, resulting in a reduced effective sensing area and low overall array area utilization. Second, when integrating multifunctional sensor arrays, there is a lack of scientific integration methods and signal decoupling techniques for different sensors. Flexible sensors fabricated using traditional screen printing have varying detection mechanisms for different physical quantities, and their output signals are often coupled (e.g., cross-sensitivity to mechanical properties and temperature). The lack of effective decoupling methods reduces the reliability of monitoring data in complex environments. These factors collectively restrict the further development of screen-printed sensors in applications requiring high density and high integration. Therefore, there is an urgent need to provide a new type of sensor array to overcome the shortcomings of existing technologies. Summary of the Invention

[0006] To address the aforementioned problems in the prior art, this invention provides a flexible temperature and stress integrated sensor array based on shielded strips and its fabrication method. The technical problem to be solved by this invention is achieved through the following technical solution:

[0007] In a first aspect, the present invention provides a flexible temperature and stress integrated sensor array based on a shielded strip, comprising:

[0008] The first conductive layer includes a plurality of first conductive wires arranged in parallel along a first direction;

[0009] The second conductive layer includes multiple second wires arranged in parallel along a second direction; the first wires and the second wires define multiple regions arranged in an array, each region including four diagonally arranged sub-regions, and each region is provided with two stress sensors and one temperature sensor.

[0010] The shielding strip layer is located between the first conductive layer and the second conductive layer, and includes multiple shielding strips arranged in parallel along the second direction, with the second conductor located on the upper surface of the shielding strips;

[0011] The first direction intersects with the second direction.

[0012] Secondly, the present invention also provides a method for fabricating a flexible temperature and stress integrated sensor array based on a shielded strip, for fabricating the aforementioned flexible temperature and stress integrated sensor array based on a shielded strip, comprising:

[0013] Provide a base;

[0014] A first conductive layer is prepared on the upper surface of the substrate, the first conductive layer comprising a plurality of first wires arranged in parallel along a first direction;

[0015] A shielding strip layer is prepared on the upper surface of the first conductive layer. The shielding strip layer includes multiple shielding strips arranged in parallel along a second direction; wherein the first direction intersects the second direction.

[0016] A second conductive layer is prepared on the upper surface of the shielding strip layer, the second conductive layer comprising a plurality of second wires arranged in parallel along a second direction;

[0017] A stress sensor is fabricated on the upper surface of a substrate, and the stress sensor is located within the area defined by the first wire and the second wire;

[0018] A temperature sensor is fabricated on the upper surface of a substrate, and the temperature sensor is located within the area defined by a first wire and a second wire.

[0019] The beneficial effects of this invention are:

[0020] This invention provides a flexible temperature and stress integrated sensor array based on shielded strips and its fabrication method. By introducing a shielded strip structure into the screen-printed row and column circuits, this design effectively eliminates crosstalk between horizontal and vertical wires in the wire arrangement through physical isolation. Compared with the traditional one-to-one lead method, this scheme significantly reduces the area of ​​non-functional wires, greatly increasing the space ratio of the sensing unit. This enables higher density sensor integration on the same substrate area, providing an efficient and low-cost hardware implementation method for large-scale, high-resolution flexible sensor array manufacturing.

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a flexible temperature and stress integrated sensor array based on shielded strips provided in an embodiment of the present invention;

[0023] Figure 2 This is a flowchart of signal decoupling provided in an embodiment of the present invention;

[0024] Figure 3 This is a flowchart of a method for fabricating a flexible temperature and stress integrated sensor array based on shielded strips, provided in an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of a method for fabricating a flexible temperature and stress integrated sensor array based on a shielded strip, provided in an embodiment of the present invention.

[0026] Figure 5 This is another schematic diagram of the fabrication method of the flexible temperature and stress integrated sensor array based on shielded strips provided in the embodiments of the present invention;

[0027] Figure 6 This is another schematic diagram of the fabrication method of the flexible temperature and stress integrated sensor array based on shielded strips provided in the embodiments of the present invention;

[0028] Figure 7 This is another schematic diagram of the fabrication method of the flexible temperature and stress integrated sensor array based on shielded strips provided in the embodiments of the present invention;

[0029] Figure 8 This is another schematic diagram of the fabrication method of the flexible temperature and stress integrated sensor array based on shielding strips provided in the embodiments of the present invention. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0031] Please see Figure 1 , Figure 1 This is a schematic diagram of a flexible temperature and stress integrated sensor array based on a shielded strip provided by an embodiment of the present invention. The flexible temperature and stress integrated sensor array based on a shielded strip provided by the present invention includes:

[0032] The first conductive layer includes a plurality of first conductive wires 10 arranged in parallel along the first direction D1;

[0033] The second conductive layer includes multiple second conductors 20 arranged in parallel along the second direction D2; the first conductor 10 and the second conductors 20 define multiple regions S arranged in an array, each region S including four diagonally arranged sub-regions, and each region S is provided with two stress sensors 30 and one temperature sensor 40.

[0034] The shielding strip layer is located between the first conductive layer and the second conductive layer, and includes multiple shielding strips 50 arranged in parallel along the second direction D2, with the second conductor 20 located on the upper surface of the shielding strips 50.

[0035] Wherein, the first direction D1 intersects with the second direction D2; optionally, the first direction D1 is perpendicular to the second direction D2.

[0036] For details, please continue to see Figure 1The flexible temperature and stress integrated sensor array based on shielded strips provided in this embodiment includes a substrate, a first conductive layer disposed on the substrate, a shielded strip layer disposed on the first conductive layer, and a second conductive layer disposed on the shielded strip layer. A shielded strip layer is disposed between the first and second conductive layers. Along a direction perpendicular to the substrate, the orthographic projection of the second conductor 20 in the second conductive layer lies within the orthographic projection range of the shielded strip 50 in the shielded strip layer, meaning the shielded strip 50 provides insulation and effectively eliminates crosstalk between the first conductor 10 and the second conductor 20. Furthermore, the first conductor 10 in the first conductive layer and the second conductor 20 in the second conductive layer define multiple sub-regions of different sizes, forming a region S composed of four sub-regions of different sizes. These four sub-regions are arranged diagonally. Each region S contains two stress sensors 30 and one temperature sensor 40. Each region S has three sub-regions, all of which contain sensors. It should be noted that the smallest region S in each region S does not contain a sensor to achieve a compact sensor array layout. From the overall sensor array layout, each temperature sensor 40 is surrounded by a stress sensor. When acquiring temperature through the temperature sensor 40, the centrally symmetrical pattern can offset some of the effects of structural changes on the resistance of the temperature sensor 40. The sensor array in this embodiment integrates the temperature sensor 40 and the stress sensor 30, and the arrangement of the sensors in the array is designed to improve space utilization and provide a hardware foundation for achieving high-density, large-scale integration of the sensor array.

[0037] In summary, this invention integrates a dual-function temperature and stress sensor on a single flexible substrate. By printing shielding strips 50 between rows and columns of wires, isolation between the wires is achieved, significantly reducing the area ratio of wires in traditional layouts, thereby greatly improving the effective utilization rate of the sensing area.

[0038] It should be noted that the first conductor 10 is a horizontally arranged conductor, and the second conductor 20 is a vertically arranged conductor. The first conductor 10 and the second conductor 20 are arranged intersectingly.

[0039] In an optional embodiment of the present invention, please continue to refer to... Figure 1 Three adjacent first conductors 10 form a first conductor unit 11, wherein in the first conductor unit 11, the distance between two adjacent first conductors in the first group is less than the distance between two adjacent first conductors in the second group.

[0040] The first conductor unit 11 and the second conductor 20 define a region S, including two first sub-regions S1 defined by a first set of two adjacent first conductors 10 and second conductors 20, and two second sub-regions S2 defined by a second set of two adjacent first conductors 10 and second conductors 20.

[0041] For details, please continue to see Figure 1 To improve space utilization and achieve high-density integration, the distances between adjacent first wires 10 are different. Three first wires 10 are used as a group of first wire units 11. The distance between two adjacent first wires in the first group is smaller than the distance between two adjacent first wires in the second group. The area between two adjacent first wires in the first group is used to arrange stress sensors 30, and the area between two adjacent first wires in the second group is used to arrange temperature sensors 40 and stress sensors 30.

[0042] In an optional embodiment of the present invention, please continue to refer to... Figure 1 In the same region S, stress sensors are installed in only one of the two first sub-regions S1. In the same region S, stress sensors are installed in one of the two second sub-regions S2, and temperature sensors 40 are installed in the other second sub-region S2. Stress sensors 30 are installed on both sides of the temperature sensor 40.

[0043] For details, please continue to see Figure 1 In this embodiment, the first sub-region S1 where stress sensors 30 are placed and the second sub-region S2 where stress sensors 30 are placed in the same region S have different sizes. In order to improve space utilization, the two stress sensors 30 in the same region S are placed in different directions.

[0044] In an optional embodiment of the present invention, the first conductive layer further includes a first electrode 12 connected to the first wire 10, a portion of the first electrode 12 connected to the first wire 10 being connected to a stress sensor 30, and a portion of the first electrode 12 connected to the first wire 10 being connected to a temperature sensor 40.

[0045] Specifically, in this embodiment, the first conductive layer further includes a first electrode 12. The position of the first electrode 12 is adapted to the sensor, that is, the position of the first electrode 12 is set according to the position of the sensor, so that the first electrode 12 can be connected to the electrode on the sensor.

[0046] In an optional embodiment of the present invention, the second conductive layer further includes a second electrode 21 connected to the second wire 20, and the second electrode 21 connected to the same second wire 20 is connected to both the stress sensor 30 and the temperature sensor 40.

[0047] Specifically, in this embodiment, the second conductive layer further includes a second electrode 21. The position of the second electrode 21 is adapted to the sensor, that is, the position of the second electrode 21 is set according to the position of the sensor, so that the second electrode 21 can be connected to the electrode on the sensor.

[0048] In an optional embodiment of the present invention, please continue to refer to... Figure 1 The first conductive layer also includes a first lead 13, one end of which is connected to the first wire 10, and the other end of which is connected to the first interface 14, which is used to insert an FPC connector.

[0049] The second conductive layer also includes a second lead 22, one end of which is connected to the second wire 20, and the other end of which is connected to the second interface 23, which is used to insert an FPC connector.

[0050] For details, please continue to see Figure 1 In this embodiment, the first lead 13 is connected to the first interface 14, and the second lead 22 is connected to the second interface 23. The first interface 14 and the second interface 23 are located on opposite sides of the sensor array. The first interface 14 and the second interface 23 are used to insert the FPC connector and connect to the back-end test circuit through the FPC connection line to complete the construction of the test system.

[0051] In an optional embodiment of the present invention, please continue to refer to... Figure 1 Two stress sensors 30 and one temperature sensor 40 within the same region S are used as a group of sensing units 60.

[0052] The resistance change of the temperature sensor 40 in the sensing unit 60 is caused by temperature, and the resistance change of the stress sensor 30 is caused by both temperature and stress.

[0053] In this embodiment, a temperature sensor 40 and two stress sensors 30 above and to the left are used as a single sensing unit 60 to illustrate the decoupling process of temperature and stress information. For the temperature sensor 40, on the one hand, after the silver paste solidifies, the internal conductive network is relatively dense, and minor deformations are insufficient to cause a significant change in its resistance; on the other hand, the centrally symmetrical pattern can offset some of the influence of structural deformation on its resistance. Therefore, it can be approximated that the temperature sensor 40 is only sensitive to temperature, and its resistance change is entirely caused by temperature changes. The relationship between the resistance change rate of the temperature sensor 40 and the amount of temperature change can be expressed by the following formula:

[0054] ;

[0055] in, This indicates the resistance value of the temperature sensor at room temperature. Indicates temperature change The change in resistance value over time. This indicates the temperature sensitivity coefficient of the temperature sensor.

[0056] For stress sensor 30, its resistance change is sensitive to both temperature and stress, and the relationship between the resistance change and these two factors is expressed by the following formula:

[0057] ;

[0058] ;

[0059] in, This indicates the resistance value of the stress sensor at room temperature. Indicates temperature change The change in resistance value over time. This indicates the temperature sensitivity coefficient of the stress sensor. The stress is represented as The change in resistance value at time This represents the stress sensitivity coefficient of the stress sensor. The elastic modulus of the material is represented by the value of the material; therefore, the total change in resistance of the stress sensor is expressed as:

[0060] .

[0061] Since the temperature sensor 40 is only sensitive to temperature, it is used to measure the average temperature at the location of the sensing unit 60. Because the sensor size is small, it can be approximately assumed that the average temperature at the entire location of the sensing unit 60 is the same, thereby obtaining the temperature of the stress sensor 30.

[0062] Further, please see Figure 2 , Figure 2 This is a flowchart illustrating signal decoupling provided in an embodiment of the present invention. In an optional embodiment of the present invention, decoupling the resistance change of the stress sensor caused by temperature and the resistance change of the stress sensor caused by stress includes:

[0063] The average temperature of the current calibration point is obtained by the temperature sensor 40 in the sensing unit 60 and used as the temperature of the stress sensor 30 in the sensing unit 60. The stress sensor 30 is calibrated in two dimensions to obtain the input and output data of a specific stress calibration point at a specific temperature.

[0064] Within the range of 25~100℃, multiple different temperature calibration points are defined, and different stresses are applied to the stress sensor 30. At each temperature calibration point, the relationship between the resistance of the stress sensor 30 and the stress is obtained.

[0065] In actual measurement, the resistance-stress curve is selected based on the current temperature corresponding to the stress sensor 30; the range in which the resistance lies is obtained based on the resistance of the stress sensor 30; and the stress value is obtained by interpolation based on the linear expression of this range, expressed as:

[0066] ;

[0067] in, This represents the stress value predicted using linear interpolation. This is the current resistance value of the stress sensor. and This represents an undetermined coefficient used to characterize the linear relationship between stress and resistance;

[0068] Furthermore, the resistance value The interval of the linear segment is The corresponding stress range is The general formula for outputting the linear expression on each interval is:

[0069] ;

[0070] in, Indicates the number of collected data. Stress data at each calibration point Indicates the number of collected data. Stress data at each calibration point Indicates the number of collected data. Resistance data at each calibration point Indicates the number of collected data. Resistance data at each calibration point Indicates the serial number of the calibration point. This indicates the current resistance value of the stress sensor. This represents the stress value predicted using linear interpolation.

[0071] The measured quantity was established using the above method. With resistance value The one-to-one correspondence is established, and the collected stress and resistance calibration point data are embedded into the backend software algorithm in the form of a table to obtain the stress output value predicted by the piecewise linear interpolation method. This efficient temperature-stress decoupling of the stress sensor 30 is achieved. This integrated strategy, working in conjunction with the linear interpolation decoupling algorithm in the backend signal processing, not only simultaneously acquires the temperature and stress distribution at multiple points on the surface of the measured structure but also identifies stress components in different directions. The system effectively suppresses the interference of ambient temperature on the output of the flexible stress sensor 30, thereby significantly improving the overall monitoring accuracy and efficiency, and providing a reliable solution for applications such as structural monitoring in high-temperature environments.

[0072] It should be noted that during two-dimensional calibration, multiple calibration points are defined, and during actual measurement, the resistance value of the point to be predicted is measured.

[0073] In this embodiment, a signal decoupling algorithm based on linear interpolation is deployed at the back end. This algorithm can accurately separate the temperature and stress components from the mixed output signal, effectively solving the problem of multi-physical quantity coupling interference and improving the accuracy and reliability of the array measurement results. The method proposed in this embodiment provides a practical integrated manufacturing and signal processing solution for the application of high-density, multi-functional flexible sensor arrays under complex working conditions.

[0074] Based on the same inventive concept, please refer to Figure 3 , Figure 3 This is a flowchart illustrating a method for fabricating a flexible temperature and stress integrated sensor array based on a shielded strip, as provided in an embodiment of the present invention. The present invention also provides a method for fabricating a flexible temperature and stress integrated sensor array based on a shielded strip, used to fabricate the flexible temperature and stress integrated sensor array based on a shielded strip provided in the above embodiments. Embodiments of the sensor array can be referred to above and will not be repeated here. The fabrication method includes:

[0075] S101, Provide a substrate.

[0076] Specifically, a 0.1mm thick polyimide film is selected as the substrate. The substrate is cleaned with anhydrous ethanol and degreased cotton balls, and then placed in a forced-air drying oven at 80℃ for 15 minutes to make the substrate flat and free from warping.

[0077] S102. A first conductive layer is prepared on the upper surface of the substrate. The first conductive layer includes a plurality of first conductive wires 10 arranged in parallel along a first direction D1; such as Figure 4 As shown.

[0078] Specifically, before printing the first conductive layer, conductive silver paste needs to be prepared. The material used for the first conductor 10 is low-temperature silver paste (01L-2210). 20g of silver paste is added to a beaker, 10 drops of paste diluent (ST1001) are added, and then a magnetic stir bar is added. The beaker is placed on a magnetic stirrer and stirred for 20 minutes to obtain conductive silver paste for printing the first conductive layer.

[0079] Further, the substrate is fixed on the screen printing table, and a 200-mesh screen is selected for printing the first conductive layer. After aligning the printed pattern with the substrate, conductive silver paste is evenly scraped off using a squeegee at a 55° angle and a pressure of 75N. The printed substrate is then placed in a forced-air drying oven and dried at 120°C for 20 minutes to complete the preparation of the first conductive layer. The first conductive layer includes a first wire 10, a first electrode 12, and a first lead 13. Along the second direction D2, the first wire 10 is 180mm long and 0.5mm wide. Each first wire 10 leads to multiple first electrodes 12 for connecting to the sensor. The dimensions of the first electrode 12 are 2mm × 2mm. Each first lead 13 is connected to a first interface 14, which is used to insert an FPC connector.

[0080] S103. A shielding strip layer is prepared on the upper surface of the first conductive layer. The shielding strip layer includes multiple shielding strips 50 arranged parallel to each other along the second direction D2; wherein the first direction D1 intersects the second direction D2; as shown in the figure. Figure 5 As shown.

[0081] Specifically, before printing the shielding strip layer, an insulating slurry needs to be prepared. The insulating material used for the shielding strip 50 is a resin slurry (09L-PETB). 15g of resin slurry is added to a beaker, 15 drops of slurry diluent (ST1001) are added, and then a magnetic stir bar is added. The beaker is placed on a magnetic stirrer and stirred for 30 minutes to obtain the insulating slurry used for printing the shielding strip 50.

[0082] Further, the substrate is fixed on the screen printing table. A 200-mesh screen is selected for the printing pattern of the shielding strip layer. After aligning the printing pattern perpendicularly with the substrate, the screen is fixed. The insulating paste is evenly scraped off using a squeegee. This process is repeated multiple times to increase the thickness of the shielding strip 50. Optionally, in this embodiment, the process is repeated 4 to 6 times, with a squeegee angle of 55° and a pressure of 80N. The printed substrate is placed in a forced-air drying oven and set to 100°C for 25 minutes to complete the preparation of the shielding strip layer. Along the first direction D1, the shielding strip 50 is 180mm long and 4mm wide.

[0083] S104. A second conductive layer is prepared on the upper surface of the shielding strip layer. The second conductive layer includes multiple second conductive wires 20 arranged parallel to the second direction D2. Figure 6 As shown.

[0084] Specifically, before printing the second conductive layer, conductive silver paste needs to be prepared. The material used for the second conductor 20 is low-temperature silver paste (01L-2210). 20g of silver paste is added to a beaker, 10 drops of paste thinner (ST1001) are added, and then a magnetic stir bar is added. The beaker is placed on a magnetic stirrer and stirred for 20 minutes to obtain conductive silver paste for printing the second conductive layer.

[0085] Further, the substrate is fixed on the screen printing table, and a 200-mesh screen is selected for printing the second conductive layer. After aligning the printed pattern with the substrate, conductive silver paste is evenly scraped off using a squeegee at a 55° angle and a pressure of 75N. The printed substrate is then placed in a forced-air drying oven and dried at 120°C for 20 minutes to complete the preparation of the second conductive layer. The second conductive layer includes a second conductor 20, a second electrode 21, and a second lead 22. Along the first direction D1, the second conductor 20 is 182mm long and 0.5mm wide. Each second conductor 20 leads to multiple second electrodes 21 for connecting to the sensor. The dimensions of the second electrode 21 are 2mm × 2mm. Each second lead 22 is connected to a second interface 23, which is used to insert an FPC connector.

[0086] S105. A stress sensor is fabricated on the upper surface of the substrate, the stress sensor being located within the region S defined by the first wire 10 and the second wire 20; as shown. Figure 7 As shown.

[0087] Specifically, before printing the stress sensor layer, a stress-sensitive paste needs to be prepared first. The material used for the stress sensor 30 is a mixture of graphene paste (XF181) and commercial silver paste (01L-2211D). 8g of graphene paste and 2g of commercial silver paste are added to a beaker, along with 5 drops of paste thinner (ST1001). A magnetic stir bar is then added, and the beaker is placed on a magnetic stirrer and stirred for 40 minutes to ensure thorough mixing. This yields the sensitive paste used for printing the stress sensor 30. It is worth noting that graphene paste, as a material with a negative temperature coefficient, combined with silver paste, which has a positive temperature coefficient, allows for control of the resistance and temperature coefficient of the final mixed paste, thereby reducing temperature-related interference with the stress sensor 30.

[0088] Further, the substrate is fixed on the screen printing table. A 250-mesh screen is selected for printing the stress sensor layer pattern. After aligning the printing pattern with the substrate, the screen is fixed, and the mixed paste is evenly scraped off using a squeegee at a 55° angle and a pressure of 75N. The printed substrate is placed in a forced-air drying oven and dried at 120°C for 25 minutes to complete the preparation of the stress sensor layer. The stress sensor 30 is grid-shaped with a linewidth of 0.8mm, a straight segment length of 13mm, and a semi-circular diameter of 1.4mm at the end. Electrodes are led out on both sides, with dimensions of 2mm × 2mm. It should be noted that the electrodes led out by the stress sensor 30 cover the first electrode 12 or the second electrode 21.

[0089] S106. A temperature sensor 40 is fabricated on the upper surface of the substrate. The temperature sensor 40 is located within the region S defined by the first wire 10 and the second wire 20. Figure 8 As shown.

[0090] Specifically, before printing the temperature sensor layer, a temperature-sensitive paste needs to be prepared. The material used for the temperature sensor 40 is commercial silver paste (3310). 10g of commercial silver paste is added to a beaker, 5 drops of paste diluent (ST1001) are added, and then a magnetic stir bar is added. The beaker is placed on a magnetic stirrer and stirred for 20 minutes to obtain the sensitive paste for printing the temperature sensor 40.

[0091] Further, the substrate is fixed on the screen printing table, and a 200-mesh screen is selected for printing the temperature sensor layer. After aligning the printed pattern with the substrate, the screen is fixed, and the sensitive paste is evenly scraped off using a squeegee at a 55° angle and a pressure of 70N. The printed substrate is then placed in a forced-air drying oven and set to 125°C for 20 minutes to complete the preparation of the temperature sensor layer. The temperature sensor 40 is U-shaped, with a line width of 0.8mm and dimensions of 14mm × 14mm. Electrodes with dimensions of 2mm × 2mm are led out on both sides. It should be noted that the electrodes led out by the temperature sensor 40 cover the first electrode 12 or the second electrode 21.

[0092] In an optional embodiment of the present invention, it further includes:

[0093] A polyimide film is encapsulated on the upper surface of the sensor array to prevent the sensors from malfunctioning due to oxidation.

[0094] In an optional embodiment of the present invention, the substrate is a polyimide substrate with dimensions of 200mm × 200mm. The first wire 10 is a transverse wire, with 12 wires in total. The second wire 20 is a longitudinal wire, with 8 wires in total. Branch electrodes, namely first electrodes 12 and second electrodes 21, are led out from the branches of the first wire 10 and the second wire 20 for connecting to the sensor. Each first wire 10 leads out 4 first electrodes 12. Optionally, such as... Figure 6 As shown, the first, third, fifth, and seventh second wires 20 each lead out eight second electrodes 21 for connecting stress sensors 30, and the second, fourth, sixth, and eighth second wires 20 each lead out four second electrodes 21 for connecting temperature sensors 40. The sensor includes 32 stress sensors 30 and 16 temperature sensors 40. The stress sensors 30 are grid-shaped, and the temperature sensors 40 are U-shaped. Multiple regions S are defined by the first wire 10 and the second wire 20. A region S is formed by four sub-regions of different sizes. The four sub-regions are arranged diagonally. Sensors are set in three sub-regions within a region S. A temperature sensor 40 is placed in one sub-region, and stress sensors 30 are placed in two sub-regions. The two stress sensors 30 are located on the left and top sides of the temperature sensor 40, respectively.

[0095] In summary, this invention provides a flexible temperature and stress integrated sensor array based on shielded strips. Addressing the problems of low space utilization and interference between row and column conductors caused by the inability to effectively separate the wires at both ends of the sensor electrodes during current screen-printed sensor array manufacturing, this invention proposes a method for manufacturing sensor row and column conductors based on shielded strips. Furthermore, considering that stress sensors manufactured using current screen-printing technology cannot overcome interference from high-temperature environments, this invention proposes an integrated method for temperature and stress sensors, coupled with a linear interpolation decoupling algorithm, which improves the measurement efficiency of physical quantities while ensuring the measurement stability of each sensor.

[0096] 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.

[0097] 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. Moreover, the specific features or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0098] 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 flexible temperature and stress integrated sensor array based on shielded strips, characterized in that, include: The first conductive layer includes a plurality of first conductive wires arranged in parallel along a first direction; The second conductive layer includes a plurality of second conductive wires arranged in parallel along a second direction; The first and second wires define multiple regions of the array arrangement. Each region includes four diagonally arranged sub-regions, and each region is equipped with two stress sensors and one temperature sensor. A shielding strip layer, located between the first conductive layer and the second conductive layer, includes multiple shielding strips arranged in parallel along a second direction, and the second conductor is located on the upper surface of the shielding strips; Wherein, the first direction intersects with the second direction; Three adjacent first wires form a first wire unit, wherein in the first wire unit, the distance between two adjacent first wires in the first group is less than the distance between two adjacent first wires in the second group; The first conductor unit and the second conductor define a region, including two first sub-regions defined by a first set of two adjacent first conductors and the second conductor, and two second sub-regions defined by a second set of two adjacent first conductors and the second conductor; In the same region, only one of the two first sub-regions is equipped with a stress sensor, and in the same region, one of the two second sub-regions is equipped with a stress sensor and the other is equipped with a temperature sensor, with the stress sensor located on both sides of the temperature sensor.

2. The flexible temperature and stress integrated sensor array based on shielded strips according to claim 1, characterized in that, The first conductive layer further includes a first electrode connected to the first wire, a portion of which is connected to the first electrode connected to the first wire and is connected to the stress sensor, and a portion of which is connected to the first electrode connected to the first wire and is connected to the temperature sensor.

3. The flexible temperature and stress integrated sensor array based on shielded strips according to claim 1, characterized in that, The second conductive layer also includes a second electrode connected to the second wire, and the second electrode connected to the same second wire is connected to both the stress sensor and the temperature sensor.

4. The flexible temperature and stress integrated sensor array based on shielded strips according to claim 1, characterized in that, The first conductive layer further includes a first lead, one end of which is connected to the first wire, and the other end of which is connected to a first interface for inserting an FPC connector. The second conductive layer further includes a second lead, one end of which is connected to the second wire, and the other end of which is connected to a second interface for inserting an FPC connector.

5. The flexible temperature and stress integrated sensor array based on shielded strips according to claim 1, characterized in that, Two stress sensors and one temperature sensor within the same area are considered as a group of sensing units; wherein... The resistance change of the temperature sensor in the sensing unit is caused by temperature, and the resistance change of the stress sensor is caused by both temperature and stress.

6. The flexible temperature and stress integrated sensor array based on shielded strips according to claim 5, characterized in that, Decoupling the resistance change of the stress sensor caused by temperature and the resistance change of the stress sensor caused by stress includes: During two-dimensional calibration, multiple different temperature calibration points are defined within the range of 25~100℃. At each temperature calibration point, different stresses are applied to the stress sensor to obtain the curve showing the relationship between the resistance of the stress sensor and the stress. In actual measurement, the temperature sensor in the sensing unit is used to obtain the temperature at the current location of the stress sensor. Based on the current temperature, the resistance-stress relationship curve of the stress sensor is selected, and the range of resistance is obtained through the resistance of the stress sensor. and the corresponding stress range The stress predicted by the stress sensor is calculated using a linear interpolation formula, expressed as: ； in, Indicates the number of collected data. Stress data at each calibration point Indicates the number of collected data. Stress data at each calibration point Indicates the number of collected data. Resistance data at each calibration point Indicates the number of collected data. Resistance data at each calibration point Indicates the serial number of the calibration point. This indicates the current resistance value of the stress sensor. This represents the stress value predicted using linear interpolation.

7. A method for fabricating a flexible temperature and stress integrated sensor array based on a shielded strip, used to fabricate the flexible temperature and stress integrated sensor array based on a shielded strip as described in any one of claims 1 to 6, characterized in that, include: Provide a base; A first conductive layer is prepared on the upper surface of the substrate, the first conductive layer comprising a plurality of first wires arranged in parallel along a first direction; A shielding strip layer is prepared on the upper surface of the first conductive layer, the shielding strip layer comprising a plurality of shielding strips arranged in parallel along a second direction; wherein the first direction intersects the second direction; A second conductive layer is prepared on the upper surface of the shielding strip layer, the second conductive layer comprising a plurality of second wires arranged in parallel along a second direction; A stress sensor is fabricated on the upper surface of the substrate, the stress sensor being located within the area defined by the first wire and the second wire; A temperature sensor is fabricated on the upper surface of the substrate, the temperature sensor being located within the region defined by the first wire and the second wire; wherein, three adjacent first wires form a first wire unit, and within the first wire unit, the distance between two adjacent first wires in a first group is less than the distance between two adjacent first wires in a second group; the first wire unit and the second wire define a region, including two first sub-regions defined by the first group of two adjacent first wires and the second wire, and two second sub-regions defined by the second group of two adjacent first wires and the second wire; a stress sensor is provided in only one of the two first sub-regions within the same region, and a stress sensor is provided in one of the two second sub-regions within the same region, while a temperature sensor is provided in the other second sub-region, with stress sensors provided on both sides of the temperature sensor.

8. The method for fabricating a flexible temperature and stress integrated sensor array based on a shielded strip according to claim 7, characterized in that, Also includes: A polyimide film is encapsulated on the upper surface of the sensor array.

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