Multi-parameter surface acoustic wave sensor based on microstructure regulation and control and manufacturing method

Abstract

The invention provides a multi-parameter surface acoustic wave sensor based on microstructure regulation and control, and relates to the technical field of surface acoustic wave sensors, the sensor comprises a gradient nano-composite structure, a periodic microporous structure, a multi-parameter sensing unit and antenna integrated module, and components and orientation gradient structures of a gradient nano-composite layer, the high temperature resistance and acoustic performance of the material are improved; the periodic microporous structure disperses thermal stress, regulates and controls the sound field, and reduces the propagation attenuation of the surface acoustic wave. The multi-parameter sensing unit integrates a temperature sensing unit, a pressure sensing unit and a strain sensing unit, accurate monitoring and decoupling are achieved, and the measurement error is small. The flexible substrate is matched with the curved surface of the special-shaped component for installation, the antenna integrated module is high in signal transmission efficiency and good in stability at high temperature after being optimized, the manufacturing method adopts mature MEMS processes such as photoetching and etching, compatibility is high, batch production is easy, the problem of multi-parameter monitoring of the special-shaped component in the severe environment is effectively solved, and wide application prospects are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of surface acoustic wave sensors, in particular to a multi-parameter surface acoustic wave sensor based on microstructure regulation and a manufacturing method. BACKGROUND

[0002] In the fields of aerospace, energy equipment, intelligent infrastructure, etc., the structural health monitoring of special-shaped components in harsh environments such as high temperature, high pressure, and strong radiation is crucial, and it is necessary to collect multi-parameter signals such as temperature, pressure, and strain in real time. The traditional surface acoustic wave (SAW) sensor has the following shortcomings: first, the thermal-mechanical-acoustic performance coupling of the material in a high-temperature environment is severely disturbed, resulting in large signal attenuation and low measurement accuracy; second, the sensor has poor adaptability to the curved surface of the special-shaped component and is not flexible enough to cause additional stress; third, signal crosstalk exists when multiple parameters are integrated, making it difficult to achieve accurate decoupling; fourth, the wireless transmission module has poor compatibility with the sensor, and the signal transmission is unstable at high temperatures.

[0003] In the prior art, although the performance of the sensor is improved through material modification or structural optimization, there is a lack of systematic regulation of nano-enhanced phase distribution and micro-pore array microstructure. On the surface of the special-shaped component, there are usually complex curved surface features, such as convex or concave surfaces with a radius of curvature less than 50 mm. The traditional rigid substrate surface acoustic wave sensor cannot be closely attached to the curved surface, which not only causes the performance of the sensor to drift, but also may accelerate the fatigue damage of the component. It is difficult to simultaneously meet the requirements of high temperature resistance, high sensitivity, multi-parameter integration, and stable wireless transmission. Therefore, there is an urgent need for a multi-parameter surface acoustic wave sensor based on microstructure regulation, which can fundamentally solve the problem of multi-parameter monitoring of special-shaped components in harsh environments through precise design and systematic regulation of the microstructure of the sensor, and provide technical support for the safe operation of key equipment under extreme conditions. SUMMARY

[0004] To solve the above problems, the present application provides a multi-parameter surface acoustic wave sensor based on microstructure regulation, comprising: a flexible substrate; a gradient nano-composite layer covering the surface of the flexible substrate; a periodic micro-pore structure distributed in the gradient nano-composite layer and the flexible substrate; a multi-parameter sensitive unit integrated on the surface of the gradient nano-composite layer, including a temperature sensitive unit, a pressure sensitive unit, and a strain sensitive unit; and an antenna integrated module coplanarly integrated with the multi-parameter sensitive unit on the flexible substrate for realizing wireless signal transmission.

[0005] Further, the gradient nano-composite layer includes a composition gradient structure and an orientation gradient structure. In the composition gradient structure, the nano-reinforced phase is distributed along the thickness direction of the flexible substrate in a gradient manner, and the content of the nano-reinforced phase in the surface layer is higher than that in the inner layer. In the orientation gradient structure, the alumina nanowires are arranged along the propagation path of the surface acoustic wave.

[0006] Further, the periodic micro-hole structure includes a hexagonal close-packed micro-hole array distributed in the sensitive area, and a randomly distributed micro-hole distributed in the non-sensitive area.

[0007] Further, the temperature sensitive unit is a Rayleigh wave interdigital transducer, which realizes temperature detection by the change of Rayleigh wave propagation speed with temperature; The pressure sensitive unit includes a thin film cavity and a pressure sensitive interdigital transducer located above the cavity, which realizes pressure detection by the stress change modulation of the surface acoustic wave propagation speed caused by the bending of the thin film; and The strain sensitive unit is a Love wave interdigital transducer, and the periodic micro-hole structure is distributed in the transducer area, which enhances the modulation effect of strain on the propagation of surface acoustic wave by stress concentration at the edge of the micro-hole.

[0008] Further, the shape of the periodic micro-hole structure is circular, square or elliptical, and the micro-hole array is made by photolithography and etching process.

[0009] Further, the antenna integrated module includes a flexible patch array antenna for signal matching transmission with the multi-parameter sensitive unit; the flexible patch array antenna takes high-temperature-resistant polyimide as the substrate, and gold or aluminum as the radiator material, and the curvature radius of the radiator is optimized by electromagnetic simulation, and the feed point position is located on the central axis of the antenna.

[0010] Further, the sensor processes the output signal of the multi-parameter sensitive unit by the multi-physical field coupling model and the iterative decoupling algorithm, to realize accurate decoupling of temperature, pressure and strain parameters.

[0011] Further, in the multi-physical field coupling model and the iterative decoupling algorithm, the shift of the relative resonant frequency of the temperature sensitive unit and the pressure sensitive unit is represented as: ; Wherein, represents the resonant frequency when the initial temperature is and the initial pressure is ; represents the resonant frequency when the temperature is T and the initial pressure is ; and are the first-order and second-order frequency temperature coefficients, respectively, is the temperature coefficient of the resonant frequency of the temperature sensitive unit, is the temperature coefficient of the resonant frequency of the pressure sensitive unit, and The difference between the two values; pressure sensitivity is represented as: ; wherein, is the slope, is the intercept.

[0012] Further, the shift in the relative resonant frequency of the pressure sensitive unit in the sensor under the combined influence of temperature T and pressure P is represented as: ; wherein, represents the resonant frequency of the pressure sensitive unit at temperature and initial pressure ; represents the resonant frequency of the pressure sensitive unit at temperature and initial pressure ; The shift in the relative resonant frequency of the temperature sensitive unit is represented as: ; The output frequency of the pressure sensitive unit is represented as: ; The demodulated pressure value is calculated as: .

[0013] The present application also proposes a manufacturing method of the above-mentioned multi-parameter acoustic surface wave sensor based on microstructure regulation, comprising the following steps: (1) Preparing a gradient nanocomposite layer: mixing a nano-enhanced phase such as silicon carbide nanoparticles with a flexible substrate material precursor to form a suspension, placing the suspension in a centrifuge tube, obtaining a nano-particle suspension with gradient distribution of components through a centrifugal process, and forming a gradient structure of components after thermal curing; injecting a precursor solution containing aluminum oxide nanowires into a mold with parallel electrodes, applying an electric field to induce directional arrangement of nanowires, and forming an orientation gradient structure through a solidification process; (2) Preparing a periodic micropore structure: patterning on the gradient nanocomposite layer and flexible substrate by deep ultraviolet lithography combined with flexible mask technology, etching to form a hexagonal close-packed micropore array and randomly distributed micropores by a reactive ion etching process; (3) Preparing a multi-parameter sensitive unit: using micro-nano processing technologies such as photolithography-etching, precisely manufacturing a micropore array on the surface of the piezoelectric material in the transducer area, using periodic arrangement to achieve uniform response to pressure; (4) Preparation of integrated antenna module: for high-temperature flexible piezoelectric material, chemical solution deposition technology is adopted, high-quality P(VDF-TrFE) film is grown on the polyimide substrate by controlling the solution concentration, deposition temperature and time parameters.

[0014] Compared with the prior art, the present application has the following beneficial effects: 1. Microstructure regulation optimizes performance: the gradient nanocomposite structure improves the high-temperature resistance and acoustic performance of the material through composition and orientation gradient, and the periodic microporous structure induces thermal stress concentration and regulates the acoustic field, reduces the propagation attenuation of the surface acoustic wave, and improves the stability of the sensor at high temperature.

[0015] 2. Accurate monitoring of multiple parameters: the integration of temperature, pressure and strain sensitive units enables simultaneous measurement of temperature, pressure and strain, and the decoupling algorithm effectively reduces signal interference and improves measurement accuracy.

[0016] 3. Curved surface adaptation and wireless transmission: the flexible substrate (PI) is adapted to the curved surface installation of special-shaped components, which can meet the installation requirements of the antenna in different curved surface environments and ensure the stable operation of the sensor in high temperature environment. In addition, the integrated antenna design ensures the signal transmission efficiency at high temperature through curvature optimization.

[0017] 4. Combined with multi-physical field coupling model and iterative decoupling algorithm: fully consider the dynamic changes of characteristic parameters of materials under the action of multi-physical field, and take multi-disciplinary theories such as elasticity, piezoelectricity and heat conduction as the core to build the model.

[0018] 5. Strong process compatibility: mature MEMS processes such as photolithography, etching and deposition are adopted, and the gradient structure and microporous structure do not need additional complex steps and are easy to produce. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a cross-sectional view of the gradient nanocomposite structure of the embodiment of the present application; Figure 2 is a schematic view of the periodic microporous structure of the embodiment of the present application; Figure 3 is a schematic view of the temperature-pressure-strain multi-parameter strain integrated structure of the embodiment of the present application.

[0020] In the figure: 1 is a temperature sensitive unit, 2 is a pressure sensitive unit, 3 is a periodic micropore, and 4 is a pressure sensitive unit. DETAILED DESCRIPTION

[0021] The application will be described in detail below with specific examples. The following examples will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the application. These are within the scope of protection of the application.

[0022] Example 1 A multi-parameter surface acoustic wave sensor based on microstructure regulation, comprising: a flexible substrate; a gradient nanocomposite layer covering the surface of the flexible substrate; a periodic micropore structure distributed in the gradient nanocomposite layer and the flexible substrate; a multi-parameter sensitive unit integrated on the surface of the gradient nanocomposite layer, including a temperature sensitive unit, a pressure sensitive unit and a strain sensitive unit; an antenna integrated module coplanarly integrated with the multi-parameter sensitive unit on the flexible substrate for realizing wireless signal transmission.

[0023] The gradient nanocomposite layer includes a composition gradient structure and an orientation gradient structure; In the composition gradient structure, the nano-reinforced phase is distributed in a gradient along the thickness direction of the flexible substrate, and the nano-reinforced phase content of the surface layer is higher than that of the inner layer; In the orientation gradient structure, the alumina nanowires are arranged in a direction along the surface acoustic wave propagation path.

[0024] The periodic micropore structure includes a hexagonal close-packed micropore array distributed in the sensitive area, and a randomly distributed micropore distributed in the non-sensitive area. Preferably, the shape of the periodic micropore structure is circular, square or elliptical, and the micropore array is made by photolithography and etching process.

[0025] The temperature sensitive unit is a Rayleigh wave interdigital transducer, which realizes temperature detection by the change of Rayleigh wave propagation speed with temperature; The pressure sensitive unit includes a thin film cavity and a pressure sensitive interdigital transducer located above the thin film cavity, which realizes pressure detection by the stress change modulation of the surface acoustic wave propagation speed caused by the bending of the thin film; The strain sensitive unit is a Love wave interdigital transducer, and the periodic micropore structure is distributed in the Love wave interdigital transducer area, which enhances the modulation effect of strain on the surface acoustic wave propagation by stress concentration at the edge of the micropore.

[0026] The antenna integrated module includes a flexible patch array antenna for signal matching transmission with the multi-parameter sensitive unit; the flexible patch array antenna takes polyimide as the substrate, and the radiator material is gold or aluminum, the curvature radius of the radiator is optimized by electromagnetic simulation, and the feed point position is located on the central axis of the antenna.

[0027] As shown in Figure 1 The gradient nano-composite structure includes a composition gradient structure and an orientation gradient structure. In the composition gradient structure, the planned nano-reinforced phase, such as silicon carbide nanoparticles, can effectively resist high temperature erosion, maintain higher flexibility inside, and ensure the structural integrity and variability of the material as a whole at high temperature; in the orientation gradient structure, the alumina nanowires are arranged in the direction of the surface acoustic wave propagation path, reducing the propagation attenuation, and the orientation is fixed by electric field induction and solidification process. The gradient change of composition and orientation gives the material anisotropic properties, which has different effects on the propagation of surface acoustic waves in different directions.

[0028] As shown in Figure 2 The periodic micro-hole structure is distributed in the gradient nano-composite layer and the flexible substrate, and the sensitive area adopts a hexagonal close-packed micro-hole array, so that the thermal expansion stress of the material at high temperature can be uniformly transmitted in all directions, avoiding stress concentration caused by uneven local pore distribution; the non-sensitive area adopts randomly distributed micro-holes to balance the flexibility and thermal stress buffering capacity, and according to the multi-physical field coupling analysis results, the micro-hole structure parameters are optimized and adjusted.

[0029] As shown in Figure 3 The multi-parameter sensitive unit is integrated on the surface of the gradient nano-composite layer: the temperature sensitive unit realizes temperature detection by using the linear change of Rayleigh wave velocity with temperature; the pressure sensitive unit is located above the thin film cavity, and realizes pressure detection by modulating the propagation of surface acoustic waves through the bending stress of the thin film; the strain sensitive unit is in the Love wave interdigital transducer region (IDT), and a periodic micro-hole array is distributed in the region, and the strain response is amplified by the stress concentration at the edge of the micro-hole to improve the detection sensitivity.

[0030] The antenna integrated module and the multi-parameter sensitive unit are coplanarly integrated on the module with high-temperature-resistant polyimide (PI) as the substrate, and a flexible patch array antenna is adopted. The curvature radius is optimized by electromagnetic simulation technology, and the position of the feeding point is adjusted to determine the input impedance matching and signal transmission efficiency of the antenna, ensuring low-noise and high-sensitivity transmission of wireless signals at high temperature.

[0031] Embodiment 2 A preparation method of a multi-parameter surface acoustic wave sensor based on microstructure regulation includes the following steps: Step 1: Silicon carbide (SiC) nanoparticles with a particle size of 150 nm and a purity of ≥99.5% are mixed with a polyimide precursor to form a uniform suspension by ultrasonic dispersion. A desktop high-speed centrifuge is used with a speed gradient setting of 3000 r / min (10 min) → 5000 r / min (15 min) → 8000 r / min (20 min) and a centrifugation temperature of 20-25°C. After centrifugation, the SiC content in the upper layer of the suspension is lower (0.5-2 wt%) and higher in the lower layer (3-5 wt%), forming a composition gradient distribution along the centrifugal direction. The gradient suspension after centrifugation is transferred to a polytetrafluoroethylene mold (the inner wall is coated with a release agent), vacuum degassing for 30 min to remove bubbles and avoid pore formation after solidification. Next, aluminum oxide (Al2O3) nanowires (diameter 100 nm, aspect ratio 20-50, content 0.5-2 wt%) are added to the base precursor, stirred and dispersed for 20 min. A parallel plate electrode is used to apply a direct current electric field with a strength of 1000 V / cm, the electric field direction is consistent with the preset surface acoustic wave propagation direction, and the action time is 60 min. Then, the above heat curing program is completed to form an oriented gradient structure with Al2O3 nanowires aligned along the surface acoustic wave direction.

[0032] Step 2: Etch a circular / polygonal thin film cavity in a specific area of the substrate, and prepare an IDT structure above the thin film cavity. First, place the substrate in acetone, anhydrous ethanol, and deionized water for ultrasonic cleaning for 3 min, then blow dry with nitrogen. Second, place the cleaned LGS substrate on a 120°C baking table for 10 min to enhance the adhesion between the substrate and the photoresist. Third, place the dried substrate in a spin coater and spin at low speed 500 rpm for 10 s and high speed 2500 rpm for 40 s. Place the spin-coated substrate on a heating table and bake at 65°C for 7 min and 95°C for 37 min. Fourth, place the mask and substrate under the photolithography machine for exposure. After exposure, remove the substrate from the mask and place it on a heating table at 65°C for 5 min and 95°C for 15 min. Finally, develop the exposed substrate using the SU8 photoresist developer until the circular / polygonal structure is fully developed. After development, rinse the developer with deionized water and dry with nitrogen. Fifth, mix hydrochloric acid and phosphoric acid in a 1:1 volume ratio and heat to 80°C in a water bath. After etching to the desired height, remove the substrate from the etching solution and immerse it in acetone solution to remove the SU8 photoresist protective layer, and finally obtain a substrate with grooves.

[0033] Step 3: The surface of the substrate is treated with oxygen plasma to improve the surface hydrophilicity, and a positive photoresist (such as AZ6130) is spin-coated at a speed of 4000 r / min (resist thickness 1-3 μm), the pre-baking temperature is 100°C, and the time is 90 s. Then, a deep ultraviolet lithography machine is used, the exposure dose is 300 mJ / cm², the exposure time is 10 s, the PET flexible mask thickness is 100 μm, and the pattern corresponds to the sensitive area of the hexagonal close-packed micro-hole array and the non-sensitive area of the random micro-hole distribution. After lithography, the corresponding developer is used for 30-60 s, rinsed with deionized water, and dried with nitrogen. A post-baking at 120°C for 1 min is performed to enhance the adhesion of the photoresist to the substrate. Finally, a reactive ion etching (RIE) process is used to etch the sensitive area to a hexagonal close-packed micro-hole array (pore size 5-20 μm, pitch 10-50 μm) and the non-sensitive area to a random micro-hole distribution. The etched substrate is ultrasonically cleaned in acetone for 5 min to remove residual photoresist.

[0034] Step 4: The electrode is deposited on the surface of the substrate by magnetron sputtering, platinum (pt) is selected as the target material, and a lithography-etching process is used to prepare the Rayleigh wave interdigital transducer (IDT), with the following parameters: finger width 5-20 μm, electrode layer thickness 200 nm, electrode pair number 50-100 pairs, and period matching Rayleigh wave wavelength.

[0035] Step 5: The antenna radiator pattern is defined in the edge area of the substrate by lithography-etching, and a metal layer (thickness 0.5-2 μm) is deposited by magnetron sputtering technology in physical vapor deposition (PVD).

[0036] Step 6: The antenna curvature radius (50-500 mm) and feed point position are optimized to match the input impedance with the output impedance of the above-mentioned sensitive unit, so that the electrical signal generated by the sensitive unit can be maximally radiated through the antenna, while reducing energy loss caused by signal reflection. A vector network analyzer (VNA) is used to connect the output end of the sensitive unit and the input end of the antenna to measure the reflection coefficient (S 11 Parameter). When S 11 ≤-10 dB (meaning that the reflected energy is ≤10%, and the transmitted energy is ≥90%), it is considered that good matching has been achieved.

[0037] Step 7: The output end of each sensitive unit is connected to the antenna feed point by wire bonding technology, an ultrasonic bonding machine is used, the wire material is high-temperature-resistant gold wire (diameter 25-50 μm), and the bonding temperature is 150-200°C.

[0038] Example 3 In the multi-physical field coupling model and the iterative decoupling algorithm, the relative resonance frequency shift of the temperature sensitive unit and the pressure sensitive unit is represented as: ; wherein, f0 represents the resonant frequency when the initial temperature is f0 represents the resonant frequency when the initial temperature is and are the first and second order frequency temperature coefficients, respectively. The pressure sensitivity at a certain temperature can be represented as follows, where is the slope, and is the intercept: ; The shift in the relative resonant frequency of the pressure sensitive unit in the sensor under the combined influence of temperature T and pressure P is represented as: where f0 represents the resonant frequency when the initial temperature is f0 represents the resonant frequency when the initial temperature is is the pressure sensitivity.

[0039] The shift in the relative resonant frequency of the temperature sensitive unit is represented as: ; Since the temperature also has an influence on the pressure sensitive unit, the influence of the temperature on the pressure sensitive unit needs to be considered when demodulating, so the output frequency of the pressure sensitive unit is the initial frequency plus the changes in the resonant frequency caused by the pressure and the temperature, respectively, and the output frequency is represented as: ; The demodulated pressure value is calculated as: .

[0040] The above describes specific embodiments of the present application. It should be understood that the present application is not limited to the specific embodiments described above, and various changes or modifications can be made by those skilled in the art within the scope of the claims, which do not affect the essential content of the present application. In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.​​​​​​​

Claims

1. A multi-parameter microstructure-based control acoustic surface wave sensor, characterized in that, The application relates to a multi-parameter sensitive surface acoustic wave sensor, which comprises the following parts: a flexible substrate; a gradient nanocomposite layer covering the surface of the flexible substrate; a periodic micropore structure distributed in the gradient nanocomposite layer and the flexible substrate; a multi-parameter sensitive unit integrated on the surface of the gradient nanocomposite layer, which comprises a temperature sensitive unit, a pressure sensitive unit and a strain sensitive unit; and an antenna integrated module integrated on the flexible substrate and coplanar with the multi-parameter sensitive unit, which is used for realizing wireless signal transmission. The gradient nanocomposite layer comprises a composition gradient structure and an orientation gradient structure. In the composition gradient structure, the nano-reinforced phase is distributed in a gradient along the thickness direction of the flexible substrate, and the nano-reinforced phase content of the surface layer is higher than that of the inner layer. In the orientation gradient structure, the alumina nanowires are arranged in a direction along the propagation path of the surface acoustic wave. The periodic micropore structure comprises a hexagonal close-packed micropore array distributed in a sensitive area and randomly distributed micropores distributed in a non-sensitive area. The temperature sensitive unit is a Rayleigh wave interdigital transducer, and temperature detection is realized by the change of the Rayleigh wave propagation speed with temperature. 2.The microstructure regulation based multi-parameter SAW sensor according to claim 1, wherein, The pressure sensitive unit comprises a thin film cavity and a pressure sensitive interdigital transducer located above the thin film cavity, and pressure detection is realized by the stress change modulation of the surface acoustic wave propagation speed caused by the bending of the thin film. The strain sensitive unit is a Love wave interdigital transducer, and the periodic micropore structure is distributed in the Love wave interdigital transducer area, and the modulation effect of the strain on the surface acoustic wave propagation is enhanced by the stress concentration of the micropore edge. The shape of the periodic micropore structure is circular, square or elliptical, and the micropore array is manufactured through a photoetching and etching process. 3.The microstructure-regulation-based multi-parameter SAW sensor according to claim 1, wherein, The antenna integrated module comprises a flexible patch array antenna, which is used for signal matching transmission of the multi-parameter sensitive unit; the flexible patch array antenna takes polyimide as a substrate, and the radiator material is gold or aluminum; the curvature radius of the radiator is optimized through electromagnetic simulation; and the feeding point position is located on the central axis of the antenna. 4.The microstructure-regulation-based multi-parameter SAW sensor of claim 1, wherein, The multi-physical field coupling model and the iterative decoupling algorithm are used for processing the output signals of the multi-parameter sensitive unit, so that the decoupling of the temperature, pressure and strain parameters is realized. In the multi-physical field coupling model and the iterative decoupling algorithm, the relative resonance frequency offset of the temperature sensitive unit and the pressure sensitive unit is expressed as follows: The relative resonance frequency offset of the pressure sensitive unit under the joint influence of temperature T and pressure P is expressed as follows:

5. The microstructure-regulation-based multi-parameter SAW sensor according to claim 1, wherein, The relative resonance frequency offset of the temperature sensitive unit is expressed as follows: 6.The microstructure-regulation-based multi-parameter surface acoustic wave sensor according to claim 1, wherein, The pressure value after demodulation is calculated as follows: 7.The microstructure-regulation-based multi-parameter SAW sensor according to claim 1, wherein, The application further discloses a preparation method of the multi-parameter sensitive surface acoustic wave sensor. 8.The microstructure-regulation-based multi-parameter SAW sensor according to claim 7, wherein, The method comprises the following steps: (1) mixing nano-reinforced phase silicon carbide nanoparticles and flexible substrate material precursors to form a suspension, placing the suspension in a centrifugal tube, obtaining a nano-particle suspension with a composition gradient distribution through a centrifugal process, and forming a composition gradient structure after heat curing; injecting a precursor solution containing alumina nanowires into a mold with parallel electrodes, applying an electric field to induce directional arrangement of the nanowires, and forming an orientation gradient structure through a solidification process; (2) patterning on the gradient nanocomposite layer and the flexible substrate through deep ultraviolet photoetching combined with a flexible mask technology, and etching to form a hexagonal close-packed micropore array and randomly distributed micropores through a reactive ion etching process. ； wherein represents the resonance frequency at an initial temperature of , and an initial pressure of ; represents the resonance frequency at a temperature of T, and an initial pressure of ; and are the first and second order frequency temperature coefficients, respectively, is the difference between and ; the pressure sensitivity is represented by: ； wherein is the slope, is the intercept. 9.The microstructure-regulation-based multi-parameter SAW sensor according to claim 8, wherein, ​ ； wherein, represents the resonance frequency of the pressure sensitive unit when the initial pressure is represents the resonance frequency of the pressure sensitive unit when the initial pressure is <000006 ​ ； Output frequency of pressure sensitive unit is represented as: ； ​ 。 10. A method of manufacturing a microstructure-based multi-parameter acoustic surface wave sensor according to any one of claims 1 to 9, characterized in that, ​ ​ ​ ​ (3) Micro-hole array is made on the surface of piezoelectric material in the transducer area by micro-nano processing technology such as photoetching-etching, and periodic arrangement is adopted to realize uniform response to pressure; (4) For high-temperature flexible piezoelectric material, high-quality polyvinylidene fluoride-trifluoroethylene copolymer film is grown on the polyimide substrate by controlling the solution concentration, deposition temperature and time parameters through chemical solution deposition technology.

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