Flexible array temperature-pressure sensor with high integration density and preparation method thereof

Abstract

The invention discloses a flexible array type temperature-pressure sensor with high integration density and a preparation method thereof. The sensor adopts a unique up-and-down stacking and split preparation-attachment integrated structure, and sequentially comprises a pressure-sensitive unit packaging layer, a first top electrode, a pressure-sensitive unit, a first flexible substrate, a first bottom electrode, a first insulating layer, a second insulating layer, a second bottom electrode, a second flexible substrate, a second top electrode and a temperature-sensitive unit from bottom to top, according to the dual-mode sensing array, the layout is optimized through the common electrode and the connection of the upper and lower distributed electrodes through the through holes, the integration density is remarkably improved, and a high-resolution dual-mode sensing array is realized; and the back of the array type temperature sensor and the back of the array type pressure sensor are attached together, so that the first flexible substrate and the second flexible substrate are completely overlapped in space. The device has the advantages of high density, high space matching precision, good flexibility and low manufacturing cost, and is suitable for the field needing precise pressure and temperature field synchronous measurement.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and more specifically, to a flexible array-type temperature-pressure sensor with high spatial resolution and high integration density that can be used for measuring complex surfaces or spatially distributed fields, and a method for fabricating the same. Background Technology

[0002] Temperature and pressure are two fundamental and critical physical parameters. Accurate and real-time monitoring of these parameters is of paramount importance in fields such as industrial automation, aerospace, biomedicine, environmental monitoring, and intelligent robotics. In many cutting-edge applications, such as aircraft wing surface flow field analysis, precision equipment heat dissipation management, wearable health monitoring, and electronic skin, it is not only necessary to acquire temperature and pressure information simultaneously, but also to require sensors capable of high-density, multi-point distributed measurements on two-dimensional or three-dimensional curved surfaces—that is, array-based measurement.

[0003] Currently, the mainstream technical solutions for temperature and pressure measurement are mainly divided into two categories: discrete integration and monolithic integration. Discrete sensor combination scheme: This scheme mechanically assembles and circuitically connects independent temperature sensors (such as thermocouples and thermistors) and pressure sensors (such as piezoresistive and capacitive sensors) at the system level to form a measurement unit. If an array is required, multiple such units need to be arranged. This scheme has significant drawbacks: large sensor unit size and low spatial resolution; complex wiring and poor system reliability; separate measurement points, making it difficult to guarantee the accuracy of synchronous co-position measurement of temperature and pressure; and difficulty in conforming to complex curved surfaces, limiting application flexibility.

[0004] Monolithic integrated sensor solutions: Utilizing microelectromechanical systems (MEMS) technology, this approach attempts to integrate temperature and pressure sensing elements onto a single silicon-based or other flexible substrate. Existing technologies have enabled the fabrication of some single-point temperature-pressure integrated sensors. However, scaling these up to high-density, large-scale array structures faces the following key technological bottlenecks: Process compatibility: Temperature sensors (typically based on the resistance-temperature effect of metals or semiconductors) and pressure sensors (typically based on the piezoresistive effect or strain sensing) often differ in their sensitive materials, structures, and optimal fabrication processes. Simply adding process steps can easily lead to material performance degradation and structural defects.

[0005] Interconnection and Packaging Challenges: Each sensitive element in the array requires an independent signal lead. As the array size increases, the number of leads increases dramatically, making it extremely difficult to achieve high-density, low-noise, and high-reliability interconnection wiring within a limited area. Simultaneously, ensuring the stable operation of the entire array in harsh environments (such as humidity and corrosion) places extremely high demands on packaging technology.

[0006] The need for flexibility and conformal attachment: Rigid silicon-based sensor arrays are difficult to implement for non-planar applications. Existing flexible sensor arrays are mostly fabricated using transfer printing or step-by-step integration processes, which are cumbersome, have low yields, and exhibit poor interfacial bonding strength and long-term stability between different functional layers.

[0007] In summary, existing sensor technologies struggle to simultaneously meet the comprehensive requirements of high-density arraying, precise co-location integration of temperature and pressure, simple and compatible fabrication processes, and suitability for attachment to complex curved surfaces. Therefore, there is an urgent need to develop a novel integrated fabrication method capable of efficiently and reliably manufacturing array-type integrated temperature and pressure sensors that are compact, high-performance, have good signal isolation, and possess excellent flexibility. Summary of the Invention

[0008] The present invention aims to provide a flexible array-type temperature-pressure sensor with high integration density and its fabrication method. This sensor employs a unique stacked and separate fabrication-bonding integration structure: from bottom to top, it consists of a pressure-sensitive unit encapsulation layer, a first top electrode, an array-type pressure-sensitive unit, a first flexible substrate, a first bottom electrode, a first insulating layer, a second insulating layer, a second bottom electrode, a second flexible substrate, a second top electrode, an array-type temperature-sensitive unit, a temperature-sensitive unit encapsulation layer, and conductive vias. By using shared electrodes and connecting the upper and lower distributed electrodes through vias to optimize the layout, the integration density is significantly improved (reaching 343 / cm²), achieving a high-resolution dual-mode sensing array. The backs of the array-type temperature sensor and the array-type pressure sensor are bonded together, allowing the temperature-sensitive unit and the pressure-sensitive unit to completely overlap spatially, thus achieving a high integration density of 319-343 / cm². 2 A flexible array-type temperature-pressure sensor. This invention combines the advantages of high density, high spatial matching accuracy, good flexibility, and low manufacturing cost, making it suitable for fields requiring precise simultaneous measurement of pressure and temperature fields.

[0009] The present invention discloses a flexible array-type temperature-pressure sensor with high integration density. This sensor comprises a pressure-sensitive unit encapsulation layer (1), a first top electrode (2), a pressure-sensitive unit (3), a first flexible substrate (4), a first bottom electrode (5), a first insulating layer (6), a second insulating layer (7), a second bottom electrode (8), a second flexible substrate (9), a second top electrode (10), a temperature-sensitive unit (11), a temperature-sensitive unit encapsulation layer (12), and conductive vias (13). The sensor is constructed by first using a shared electrode and an upper / lower electrode distribution on the substrate, with the pressure-sensitive unit encapsulation layer (1), the first top electrode (2), the pressure-sensitive unit (3), and the second bottom electrode (4) arranged sequentially from bottom to top. The temperature-pressure sensor is integrated by physical bonding of the first flexible substrate (4), the first bottom electrode (5), the first insulating layer (6), the second insulating layer (7), the second bottom electrode (8), the second flexible substrate (9), the second top electrode (10), the temperature-sensitive unit (11), and the temperature-sensitive unit encapsulation layer (12). Several pressure-sensitive units (3) are uniformly arranged on the first top electrode (2), several conductive vias (13) are uniformly arranged on the first flexible substrate (4) and the second flexible substrate (9), and several temperature-sensitive units (11) are uniformly arranged on the second top electrode (10). The array-type temperature sensor and the array-type pressure sensor are prepared separately and then physically bonded together.

[0010] The temperature-sensitive unit (11) and the pressure-sensitive unit (3) are completely overlapped in space, arranged vertically, with a distribution area of ​​0.36×(n-1). 2 mm 2 , where n = 10 - 15.

[0011] The spatial resolution of both the temperature-sensitive unit (11) and the pressure-sensitive unit (3) is n×n.

[0012] The density of the temperature-sensitive unit (11) and the pressure-sensitive unit (3) is 319-343 / cm³. 2 .

[0013] The temperature-sensitive units (11) are arranged in n rows and n columns. Each temperature-sensitive unit (11) has two electrodes. The right electrode is a shared electrode (10a), which is shared by the n temperature-sensitive units (11) in the same column. The left electrode is a dedicated electrode (10b), which belongs to a single temperature-sensitive unit (11). The left electrodes of the temperature-sensitive units (11) in the same row are connected through a conductive via (13) and the second bottom electrode (8) of the second flexible substrate (9) to form a conductive path. The pressure-sensitive units (3) are arranged in n rows and n columns. Each pressure-sensitive unit (3) has two electrodes. The right electrode is a shared electrode (2a), which is shared by the n pressure-sensitive units (3) in the same column. The left electrode is a dedicated electrode (2b), which belongs to a single pressure-sensitive unit (3). The left electrodes of the pressure-sensitive units (3) in the same row are connected through a conductive via (13) and the first bottom electrode (5) of the first flexible substrate (4) to form a conductive path.

[0014] A method for fabricating a flexible array-type temperature-pressure sensor with high integration density comprises the following steps: Fabrication of an array-type temperature sensor: a. A second bottom electrode (8) is set at the bottom of a second flexible substrate (9) with a thickness of 0.1 mm using an immersion gold process, and a second top electrode (10) is set at the top of the second flexible substrate (9). Several equally arranged conductive vias (13) are set on the surface of the second flexible substrate (9). b. Cover the second bottom electrode (8) at the bottom of the second flexible substrate (9) with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form a second insulating layer (7). c. Using inkjet printing, a metal oxide-based temperature-sensitive array is prepared on the top of the second flexible substrate (9) with a second top electrode (10). Using a 50µm printhead at a voltage of 10-14V, metal oxide ink is printed between the dedicated electrode (10b) and the common electrode (10a) to form an n×n array of temperature-sensitive units (11). The spacing between each temperature-sensitive unit (11) is 0.6mm. The printed temperature-sensitive unit (11) is placed in a constant temperature oven and treated at 200℃ for 90min. Then, 0.1mL of polystyrene butadiene copolymer is dropped onto the temperature-sensitive unit (11) and dried at room temperature to form a temperature-sensitive unit encapsulation layer (12), thus obtaining an n×n array temperature sensor. Fabrication of an array-type pressure sensor: d. Using an immersion gold process, a first top electrode (2) is set at the bottom of a first flexible substrate (4) with a thickness of 0.1 mm, a first bottom electrode (5) is set at the top of the first flexible substrate (4), and several uniformly arranged conductive vias (13) are set on the surface of the first flexible substrate (4). e. Cover the first bottom electrode (5) of the first flexible substrate (4) with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the first insulating layer (6). f. By screen printing, a screen printing plate with an n×n pattern with a spacing of 0.6mm is installed on the first top electrode (5), and the plate is calibrated according to the position of the first flexible substrate (4). An array-type pressure-sensitive unit (3) is prepared by using a squeegee pressure of 80-120N and a running speed of 250-400mm / s. Then, the pressure-sensitive unit (3) is placed in an oven at 120℃ for 30min. 0.2mL of polystyrene butadiene copolymer is dripped onto the pressure-sensitive unit (3) and dried at room temperature to form a pressure-sensitive unit encapsulation layer (1) to obtain an n×n array-type pressure sensor. g. The back sides of the array temperature sensor obtained in step c and the array pressure sensor obtained in step f are bonded together, so that the first flexible substrate (4) and the second flexible substrate (9) are physically bonded and integrated, completely overlapping in space, thus obtaining a high integration density of 319-343 / cm². 2 Flexible array temperature-pressure sensor.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The array-type temperature sensor and the array-type pressure sensor adopt an independent fabrication-bonding integration strategy to avoid mutual contamination or process condition conflicts between the two materials during fabrication. The two sensing units are separated by a flexible substrate and an insulating layer, forming a natural physical barrier, which helps to reduce cross interference and thermal coupling between the two signals, improve measurement independence, and can be finely adjusted during final bonding to ensure that each temperature unit and pressure unit are completely overlapped in space.

[0016] (2) The electrodes adopt a three-dimensional layout with shared electrodes and through holes connecting the upper and lower electrodes, which greatly simplifies the wiring complexity and frees up more space to increase density.

[0017] (3) The core sensing unit uses inkjet-printed temperature-sensitive materials and screen-printed pressure-sensitive materials, and the electrodes use immersion gold technology. These are all non-silicon-based, low-temperature additive manufacturing processes. They do not require the high-temperature, complex photolithography and etching equipment required by traditional MEMS, which not only greatly reduces the manufacturing cost, but also makes them fully compatible with flexible polymer substrates (such as PI films), laying the foundation for realizing a fully flexible sensor system.

[0018] (4) By reducing the unit spacing to 0.6 mm, a 10×10 sensor array achieved a high density of 343 / cm. 2The high cell density solves the problems of low density in traditional discrete integration and the complexity and difficulty in achieving high density in monolithic integration (MEMS) on flexible substrates. Attached Figure Description

[0019] Figure 1 The diagram shows the structure of the 10×10 array temperature-pressure sensor prepared according to the present invention: 1-pressure-sensitive unit encapsulation layer, 2-first top electrode, 3-pressure-sensitive unit, 4-first flexible substrate, 13-conductive via, 5-first bottom electrode, 6-first insulating layer, 7-second insulating layer, 8-second bottom electrode, 9-second flexible substrate, 13-conductive via, 10-second top electrode, 11-temperature-sensitive unit, 12-temperature-sensitive unit encapsulation layer; Figure 2 This is a structural diagram of the 10×10 array temperature sensor prepared according to the present invention; Figure 3 This is a structural diagram of the 10×10 array pressure sensor prepared according to the present invention; Figure 4 The distribution of the array-type temperature sensing unit and the top electrode of the 10×10 array-type temperature sensor prepared in this invention is as follows: 10a - common electrode in the second top electrode 10, 10b - dedicated electrode in the second top electrode 10. Figure 5 The distribution of the array pressure-sensitive unit and top electrode of the 10×10 array pressure sensor prepared in this invention is shown in Figure 2a - common electrode in the first top electrode 2, and 2b - dedicated electrode in the first top electrode 2. Detailed Implementation Example 1

[0020] This invention discloses a flexible array-type temperature-pressure sensor with high integration density. The sensor comprises a pressure-sensitive unit encapsulation layer 1, a first top electrode 2, a pressure-sensitive unit 3, a first flexible substrate 4, a first bottom electrode 5, a first insulating layer 6, a second insulating layer 7, a second bottom electrode 8, a second flexible substrate 9, a second top electrode 10, a temperature-sensitive unit 11, a temperature-sensitive unit encapsulation layer 12, and conductive vias 13. This is achieved by first employing a common electrode and an upper / lower electrode distribution on the substrate, with the elements arranged sequentially from bottom to top as follows: pressure-sensitive unit encapsulation layer 1, first top electrode 2, pressure-sensitive unit 3, first flexible substrate 4, first bottom electrode 5, first insulating layer 6, second insulating layer 7, second bottom electrode 8, second flexible substrate 9, second top electrode 10, temperature-sensitive unit 11, temperature-sensitive unit encapsulation layer 12, and conductive vias 13. The temperature-pressure sensor is integrated by physical bonding of the following components: substrate 4, first bottom electrode 5, first insulating layer 6, second insulating layer 7, second bottom electrode 8, second flexible substrate 9, second top electrode 10, temperature-sensitive unit 11, and temperature-sensitive unit encapsulation layer 12. Several pressure-sensitive units 3 are uniformly arranged on the first top electrode 2, several conductive vias 13 are uniformly arranged on the first flexible substrate 4 and the second flexible substrate 9, and several temperature-sensitive units 11 are uniformly arranged on the second top electrode 10. The array-type temperature sensor and the array-type pressure sensor are fabricated separately and then physically bonded together. The temperature-sensitive unit 11 and the pressure-sensitive unit 3 are completely overlapped in space, arranged vertically, with a distribution area of ​​0.36 × (n-1). 2 mm 2 Where n = 10⁻¹⁵; the spatial resolution is n × n; and the density is 319-343 / cm³. 2 ; The temperature-sensitive units 11 are arranged in n rows and n columns. Each temperature-sensitive unit 11 has two electrodes. The right electrode is a common electrode 10a, which is shared by the n temperature-sensitive units 11 in the same column. The left electrode is a dedicated electrode 10b, which belongs to a single temperature-sensitive unit 11. The left electrodes of the temperature-sensitive units 11 in the same row are connected to form a conductive path through the conductive via 13 and the second bottom electrode 8 of the second flexible substrate 9. The pressure-sensitive units 3 are arranged in n rows and n columns. Each pressure-sensitive unit 3 has two electrodes. The right electrode is a shared electrode 2a, which is shared by the n pressure-sensitive units in the same column. The left electrode is a dedicated electrode 2b, which belongs to a single pressure-sensitive unit 3. The left electrode of the pressure-sensitive unit 3 in the same row is connected to the first bottom electrode 5 of the first flexible substrate 4 through the conductive through hole 13 to form a conductive path. The specific operation is carried out according to the following steps: Fabrication of an array-type temperature sensor: a. A second bottom electrode 8 is provided at the bottom of a second flexible substrate 9 with a thickness of 0.1 mm using an immersion gold process, a second top electrode 10 is provided at the top of the second flexible substrate 9, and a plurality of equally arranged conductive vias 13 are provided on the surface of the second flexible substrate 9. b. Cover the second bottom electrode 8 at the bottom of the second flexible substrate 9 with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the second insulating layer 7. c. Using inkjet printing, a metal oxide-based temperature-sensitive array is prepared on the second top electrode 10 on the top of the second flexible substrate 9. Using a 50µm printhead at 12V, metal oxide ink is printed between the dedicated electrode 10b and the common electrode 10a to form a 10×10 array of temperature-sensitive units 11. The spacing between each temperature-sensitive unit 11 is 0.6mm. The printed temperature-sensitive units 11 are placed in a constant temperature oven and treated at 200℃ for 90min. Then, 0.1mL of polystyrene-butadiene copolymer is drop-coated onto the temperature-sensitive units 11 and dried at room temperature to form a temperature-sensitive unit encapsulation layer 12, thus obtaining a 10×10 array temperature sensor. Fabrication of an array-type pressure sensor: d. A first top electrode 2 is set at the bottom of a first flexible substrate 4 with a thickness of 0.1 mm using an immersion gold process, a first bottom electrode 5 is set at the top of the first flexible substrate 4, and a plurality of uniformly arranged conductive vias 13 are set on the surface of the first flexible substrate 4. e. Cover the first bottom electrode 5 disposed on the top of the first flexible substrate 4 with a PI film, and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the first insulating layer 6. f. Using a screen printing process, a screen printing plate with a 10×10 pattern with a spacing of 0.6 mm is installed on the first top electrode 5. The plate is calibrated according to the position of the first flexible substrate 4. An array-type pressure-sensitive unit 3 is prepared using a squeegee pressure of 120 N and a running speed of 400 mm / s. The unit is then placed in an oven at 120 °C for 30 min. 0.2 mL of polystyrene-butadiene copolymer is drop-coated onto the pressure-sensitive unit 3. The unit is then dried at room temperature to form a pressure-sensitive unit encapsulation layer 1, thus obtaining a 10×10 array-type pressure sensor. g. Attach the back sides of the array-type temperature sensor obtained in step c and the array-type pressure sensor obtained in step f together, so that the first flexible substrate 4 and the second flexible substrate 9 are physically bonded and integrated, completely overlapping in space, thus achieving a high integration density of 343 / cm². 2 Flexible array temperature-pressure sensor. Example 2

[0021] The aforementioned flexible array-type temperature-pressure sensor with high integration density is based on Embodiment 1: The specific operation is carried out according to the following steps: a. A second bottom electrode 8 is provided at the bottom of a second flexible substrate 9 with a thickness of 0.1 mm using an immersion gold process, a second top electrode 10 is provided at the top of the second flexible substrate 9, and a plurality of equally arranged conductive vias 13 are provided on the surface of the second flexible substrate 9. b. Cover the second bottom electrode 8 at the bottom of the second flexible substrate 9 with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the second insulating layer 7. c. Using inkjet printing, a metal oxide-based temperature-sensitive array is prepared on the second top electrode 10 on the top of the second flexible substrate 9. Using a 50µm printhead at a voltage of 10V, metal oxide ink is printed between the dedicated electrode 10b and the common electrode 10a to form a 15×15 array of temperature-sensitive units 11. The spacing between each temperature-sensitive unit 11 is 0.6mm. The printed temperature-sensitive units 11 are placed in a constant temperature oven and treated at 200℃ for 90min. Then, 0.1mL of polystyrene-butadiene copolymer is drop-coated onto the temperature-sensitive units 11 and dried at room temperature to form a temperature-sensitive unit encapsulation layer 12, thus obtaining a 15×15 array of temperature sensors. Fabrication of an array-type pressure sensor: d. A first top electrode 2 is set at the bottom of a first flexible substrate 4 with a thickness of 0.1 mm using an immersion gold process, a first bottom electrode 5 is set at the top of the first flexible substrate 4, and a plurality of uniformly arranged conductive vias 13 are set on the surface of the first flexible substrate 4. e. Cover the first bottom electrode 5 disposed on the top of the first flexible substrate 4 with a PI film, and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the first insulating layer 6. f. Using a screen printing process, a screen printing plate with a 15×15 pattern with a spacing of 0.6mm is installed on the first top electrode 5 and calibrated according to the position of the first flexible substrate 4. The pressure-sensitive unit 3 is prepared by using a squeegee pressure of 100N and a running speed of 250mm / s. Then, the pressure-sensitive unit 3 is placed in an oven at 120℃ for 30min. 0.2mL of polystyrene-butadiene copolymer is drop-coated onto the pressure-sensitive unit 3 and dried at room temperature to form the pressure-sensitive unit encapsulation layer 1, thus obtaining a 15×15 array pressure sensor. g. Attach the back sides of the array-type temperature sensor obtained in step c and the array-type pressure sensor obtained in step f together, so that the first flexible substrate 4 and the second flexible substrate 9 are physically bonded and integrated, completely overlapping in space, thus achieving a high integration density of 319 / cm². 2 Flexible array temperature-pressure sensor. Example 3

[0022] The aforementioned flexible array-type temperature-pressure sensor with high integration density is based on Embodiment 1: The specific operation is carried out according to the following steps: a. A second bottom electrode 8 is provided at the bottom of a second flexible substrate 9 with a thickness of 0.1 mm using an immersion gold process, a second top electrode 10 is provided at the top of the second flexible substrate 9, and a plurality of equally arranged conductive vias 13 are provided on the surface of the second flexible substrate 9. b. Cover the second bottom electrode 8 at the bottom of the second flexible substrate 9 with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the second insulating layer 7. c. Using inkjet printing, a metal oxide-based temperature-sensitive array is prepared on the second top electrode 10 on the top of the second flexible substrate 9. Using a 50µm printhead at 14V, metal oxide ink is printed between the dedicated electrode 10b and the common electrode 10a to form a 12×12 array of temperature-sensitive units 11. The spacing between each temperature-sensitive unit 11 is 0.6mm. The printed temperature-sensitive units 11 are placed in a constant temperature oven and treated at 200℃ for 90min. Then, 0.1mL of polystyrene-butadiene copolymer is drop-coated onto the temperature-sensitive units 11 and dried at room temperature to form a temperature-sensitive unit encapsulation layer 12, thus obtaining a 12×12 array of temperature sensors. Fabrication of an array-type pressure sensor: d. A first top electrode 2 is set at the bottom of a first flexible substrate 4 with a thickness of 0.1 mm using an immersion gold process, a first bottom electrode 5 is set at the top of the first flexible substrate 4, and a plurality of uniformly arranged conductive vias 13 are set on the surface of the first flexible substrate 4. e. Cover the first bottom electrode 5 disposed on the top of the first flexible substrate 4 with a PI film, and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the first insulating layer 6. f. Using a screen printing process, a screen printing plate with a 12×12 pattern with a spacing of 0.6mm is installed on the first top electrode 5 and calibrated according to the position of the first flexible substrate 4. The pressure-sensitive unit 3 is prepared by using a squeegee pressure of 80N and a running speed of 300mm / s. Then, the pressure-sensitive unit 3 is placed in an oven at 120℃ for 30min. 0.2mL of polystyrene-butadiene copolymer is drop-coated onto the pressure-sensitive unit 3 and dried at room temperature to form the pressure-sensitive unit encapsulation layer 1, thus obtaining a 12×12 array pressure sensor. g. Attach the back sides of the array-type temperature sensor obtained in step c and the array-type pressure sensor obtained in step f together, so that the first flexible substrate 4 and the second flexible substrate 9 are physically bonded and integrated, completely overlapping in space, thus achieving a high integration density of 331 / cm². 2Flexible array temperature-pressure sensor.

Claims

1. A flexible array-type temperature-pressure sensor with high integration density, characterized in that, This sensor is an array-type temperature-pressure sensor composed of a pressure-sensitive unit encapsulation layer (1), a first top electrode (2), a pressure-sensitive unit (3), a first flexible substrate (4), a first bottom electrode (5), a first insulating layer (6), a second insulating layer (7), a second bottom electrode (8), a second flexible substrate (9), a second top electrode (10), a temperature-sensitive unit (11), a temperature-sensitive unit encapsulation layer (12), and conductive vias (13). It is constructed by first using a common electrode and an upper / lower electrode distribution on the substrate, arranged from bottom to top as follows: pressure-sensitive unit encapsulation layer (1), first top electrode (2), pressure-sensitive unit (3), first flexible substrate (4), first bottom electrode (5), first insulating layer (6), second insulating layer (7), second bottom electrode (8), second flexible substrate (9), second top electrode (10), second temperature-sensitive unit (11), temperature-sensitive unit encapsulation layer (12), and conductive vias (13). The temperature-pressure sensor is integrated by physical bonding of the following components: bottom electrode (5), first insulating layer (6), second insulating layer (7), second bottom electrode (8), second flexible substrate (9), second top electrode (10), temperature-sensitive unit (11), and temperature-sensitive unit encapsulation layer (12). Several pressure-sensitive units (3) are uniformly arranged on the first top electrode (2), several conductive vias (13) are uniformly arranged on the first flexible substrate (4) and the second flexible substrate (9), and several temperature-sensitive units (11) are uniformly arranged on the second top electrode (10). The array-type temperature sensor and the array-type pressure sensor are fabricated separately and then physically bonded together.

2. The flexible array-type temperature-pressure sensor with high integration density according to claim 1, characterized in that, The temperature-sensitive unit (11) and the pressure-sensitive unit (3) are completely overlapped in space, arranged vertically, with a distribution area of ​​0.36×(n-1). 2 mm 2 , where n = 10 - 15.

3. The flexible array-type temperature-pressure sensor with high integration density according to claim 1, characterized in that, The spatial resolution of both the temperature-sensitive unit (11) and the pressure-sensitive unit (3) is n×n.

4. The flexible array-type temperature-pressure sensor with high integration density according to claim 1, characterized in that, The density of the temperature-sensitive unit (11) and the pressure-sensitive unit (3) is 319-343 / cm³. 2 .

5. The flexible array-type temperature-pressure sensor with high integration density according to claim 1, characterized in that, The temperature-sensitive units (11) are arranged in n rows and n columns. Each temperature-sensitive unit (11) has two electrodes. The right electrode is a shared electrode (10a), which is shared by the n temperature-sensitive units (11) in the same column. The left electrode is a dedicated electrode (10b), which belongs to a single temperature-sensitive unit (11). The left electrodes of the temperature-sensitive units (11) in the same row are connected through a conductive via (13) and the second bottom electrode (8) of the second flexible substrate (9) to form a conductive path. The pressure-sensitive units (3) are arranged in n rows and n columns. Each pressure-sensitive unit (3) has two electrodes. The right electrode is a shared electrode (2a), which is shared by the n pressure-sensitive units (3) in the same column. The left electrode is a dedicated electrode (2b), which belongs to a single pressure-sensitive unit (3). The left electrodes of the pressure-sensitive units (3) in the same row are connected through a conductive via (13) and the first bottom electrode (5) of the first flexible substrate (4) to form a conductive path.

6. A method for fabricating a flexible array-type temperature-pressure sensor with high integration density, characterized in that, Follow these steps: Fabrication of an array-type temperature sensor: a. A second bottom electrode (8) is set at the bottom of a second flexible substrate (9) with a thickness of 0.1 mm using an immersion gold process, and a second top electrode (10) is set at the top of the second flexible substrate (9). Several equally arranged conductive vias (13) are set on the surface of the second flexible substrate (9). b. Cover the second bottom electrode (8) at the bottom of the second flexible substrate (9) with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form a second insulating layer (7). c. Using inkjet printing, a metal oxide-based temperature-sensitive array is prepared on the top of the second flexible substrate (9) with a second top electrode (10). Using a 50µm printhead at a voltage of 10-14V, metal oxide ink is printed between the dedicated electrode (10b) and the common electrode (10a) to form an n×n array of temperature-sensitive units (11). The spacing between each temperature-sensitive unit (11) is 0.6mm. The printed temperature-sensitive unit (11) is placed in a constant temperature oven and treated at 200℃ for 90min. Then, 0.1mL of polystyrene butadiene copolymer is dropped onto the temperature-sensitive unit (11) and dried at room temperature to form a temperature-sensitive unit encapsulation layer (12), thus obtaining an n×n array temperature sensor. Fabrication of an array-type pressure sensor: d. Using an immersion gold process, a first top electrode (2) is set at the bottom of a first flexible substrate (4) with a thickness of 0.1 mm, a first bottom electrode (5) is set at the top of the first flexible substrate (4), and several uniformly arranged conductive vias (13) are set on the surface of the first flexible substrate (4). e. Cover the first bottom electrode (5) of the first flexible substrate (4) with a PI film and process it with a vacuum hot press at a temperature of 180°C and a pressure of 5 MPa for 90 min to form the first insulating layer (6). f. By screen printing, a screen printing plate with an n×n pattern with a spacing of 0.6mm is installed on the first top electrode (5), and the plate is calibrated according to the position of the first flexible substrate (4). An array-type pressure-sensitive unit (3) is prepared by using a squeegee pressure of 80-120N and a running speed of 250-400mm / s. Then, the pressure-sensitive unit (3) is placed in an oven at 120℃ for 30min. 0.2mL of polystyrene butadiene copolymer is dripped onto the pressure-sensitive unit (3) and dried at room temperature to form a pressure-sensitive unit encapsulation layer (1) to obtain an n×n array-type pressure sensor. g. The back sides of the array temperature sensor obtained in step c and the array pressure sensor obtained in step f are bonded together, so that the first flexible substrate (4) and the second flexible substrate (9) are physically bonded and integrated, completely overlapping in space, thus obtaining a high integration density of 319-343 / cm². 2 Flexible array temperature-pressure sensor.

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