Pressure sensor based on electromagnetic metasurface and preparation method and assembly thereof

Abstract

A pressure sensor based on electromagnetic metasurface and a preparation method and assembly thereof, the pressure sensor based on electromagnetic metasurface comprises: a plurality of periodically arranged metasurface structure units, the period size of the metasurface structure unit is less than half the wavelength of the pressure sensor at the working frequency; the metasurface structure unit comprises: a flexible substrate with opposite first and second surfaces; a metal back plate located on the first surface of the flexible substrate, the surface opposite to the flexible substrate in the metal back plate is used for receiving the measured pressure; a dielectric plate layer located on the second surface of the flexible substrate; a metal resonant unit located on the surface of the dielectric plate layer away from the flexible substrate; a protective layer located on the surface of the metal resonant unit, and the metal resonant unit is located between the dielectric plate layer and the protective layer. The present application binds the resonant frequency and the pressure, realizes the miniaturization and high endurance of the pressure sensor.

Description

Technical Field

[0001] This invention relates to the field of pressure sensors, and more specifically to a pressure sensor based on an electromagnetic metasurface, its fabrication method, and components. Background Technology

[0002] A pressure sensor is a core sensing element whose core function is to accurately convert physical pressure signals into identifiable electrical signals. With its wide applicability, it has been deeply integrated into diverse fields, becoming an indispensable key component in modern intelligent systems. With the rapid development of Internet of Things (IoT) and Micro-Electro-Mechanical Systems (MEMS) technologies, the market has placed higher demands on the miniaturization and battery life of pressure sensors. However, conventional pressure sensors require integrated signal transceiver modules and are equipped with circuit boards and batteries, resulting in large size and high power consumption.

[0003] In conventional pressure sensors, on the one hand, the sensor needs to integrate a signal transceiver module and be equipped with a signal conditioning chip and power supply to receive, process and transmit signals, resulting in a large size and high power consumption of the pressure sensor; on the other hand, these pressure sensors rely on wired readout systems, which are difficult to install and costly in special scenarios, and require additional active excitation. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a pressure sensor based on an electromagnetic metasurface and its fabrication method and components. By setting a flexible substrate and a metal resonant structure, the resonant frequency is bound to the pressure, thereby achieving miniaturization and long battery life of the pressure sensor.

[0005] To address the aforementioned technical problems, the present invention provides a pressure sensor based on an electromagnetic metasurface, comprising: a plurality of periodically arranged metasurface structural units, wherein the periodic dimension of the metasurface structural units is smaller than half the wavelength of the pressure sensor at its operating frequency; each metasurface structural unit comprises: a flexible substrate having opposing first and second surfaces; a metal backplate located on the first surface of the flexible substrate, wherein the surface of the metal backplate opposite to the flexible substrate is used to receive the measured pressure; a dielectric substrate layer located on the second surface of the flexible substrate; a metal resonant unit located on the surface of the dielectric substrate layer away from the flexible substrate; and a protective layer located on the surface of the metal resonant unit, wherein the metal resonant unit is located between the dielectric substrate layer and the protective layer.

[0006] Optionally, the thickness of the metal backing plate is 18μm to 35μm.

[0007] Optionally, the thickness of the flexible substrate is 0.2 mm to 0.6 mm.

[0008] Optionally, the plurality of metasurface structural units are arranged in a rectangular array.

[0009] Optionally, the layer thickness of the metal resonant unit is 18μm to 35μm.

[0010] Optionally, the metal resonant unit includes a first oscillator and a second oscillator that are orthogonal to each other, with the centers of the first oscillator and the second oscillator coinciding with each other.

[0011] Optionally, the first oscillator has a first arc-shaped structure at both ends, and the second oscillator has a second arc-shaped structure at both ends. The first arc-shaped structure and the second arc-shaped structure have the same center and are spaced apart from each other.

[0012] Accordingly, the technical solution of the present invention also provides a method for fabricating a pressure sensor based on an electromagnetic metasurface, for fabricating the aforementioned pressure sensor, comprising: providing a flexible substrate and a dielectric substrate layer, the flexible substrate having opposing first and second surfaces; bonding the dielectric substrate layer to the second surface of the flexible substrate; depositing a metal backplate on the first surface of the flexible substrate; forming a plurality of metal resonant units on the surface of the dielectric substrate layer away from the flexible substrate; and forming a protective layer covering the surface of the plurality of metal resonant units.

[0013] Optionally, forming a plurality of the metal resonant units includes: forming a patterned photoresist layer on the surface of the dielectric substrate layer away from the flexible substrate; forming a metal layer on the surface of the photoresist layer and the exposed surface of the dielectric substrate layer; peeling off the photoresist layer and the metal layer on the photoresist layer to form a plurality of metal resonant units located on the surface of the dielectric substrate layer; the step of bonding the dielectric substrate layer to the second side of the flexible substrate includes: forming an adhesive layer between the dielectric substrate layer and the second side of the flexible substrate to bond the dielectric substrate layer to the second side of the flexible substrate, wherein the thickness of the adhesive layer is less than 10 μm.

[0014] Accordingly, the technical solution of the present invention also provides a pressure sensor assembly based on an electromagnetic metasurface, comprising: the pressure sensor described above; and an antenna for transmitting electromagnetic waves and receiving electromagnetic waves reflected by the pressure sensor.

[0015] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: The pressure sensor based on an electromagnetic metasurface provided by this invention includes several periodically arranged metasurface structural units. The periodic dimension of each metasurface structural unit is smaller than half the wavelength of the pressure sensor at its operating frequency. Therefore, the metasurface structure can "confine" the incident electromagnetic wave energy within the structure, forming a strong localized surface field. This localized field is extremely sensitive to changes in the surface environment. Even if the pressure only causes a micrometer-level compression of the interlayer spacing (the thickness of the flexible substrate), it will drastically disturb this localized field, leading to a significant change in the reflected electromagnetic wave, thereby improving the detection accuracy of the pressure sensor. The metasurface structural unit includes: a flexible substrate with opposing first and second surfaces; a metal backplate located on the first surface of the flexible substrate, in which the surface opposite to the flexible substrate is used to receive the measured pressure; a dielectric substrate layer located on the second surface of the flexible substrate; and a metal resonant unit located on the surface of the dielectric substrate layer away from the flexible substrate. Therefore, when pressure is applied to the metal backplate, the flexible substrate undergoes elastic deformation, resulting in a decrease in layer thickness and an increase in relative permittivity. This causes a measurable shift in the resonant frequency generated by the metal resonant unit. Thus, the resonant frequency is bound to the pressure, thereby enabling the function of a pressure sensor. Because several metasurface structural units realize the function of a pressure sensor, the pressure sensor of this invention does not require a signal conditioning chip or a built-in signal transceiver module, reducing the overall space occupation of the pressure sensor and thus achieving miniaturization. Furthermore, since the pressure sensor is a passive response and does not contain energy storage components such as batteries, it is unaffected by battery life and charging frequency, thus achieving high endurance. Additionally, because the protective layer is located on the surface of the metal resonant units, which are situated between the dielectric substrate layer and the protective layer, it provides support and protection for the metal resonant units, further improving the detection accuracy of the pressure sensor. The pressure sensor provided by this invention, through several electromagnetic metasurface structures composed of a metal backplate, a flexible substrate, a dielectric substrate layer, and metal resonant units, directly maps pressure information into a resonant frequency signal. In terms of hardware, it eliminates the need for a signal conditioning chip, transceiver module, and power supply, achieving miniaturization and high endurance of the pressure sensor. Attached Figure Description

[0016] Figures 1 to 4 This is a schematic diagram of the structure of each step in the fabrication method of the pressure sensor based on electromagnetic metasurface according to an embodiment of the present invention; Figure 5 This is a graph showing the electromagnetic wave reflection coefficient of the pressure sensor according to an embodiment of the present invention under different pressures. Figure 6 This is a graph showing the relationship between the resonant frequency of the pressure sensor in this embodiment of the invention and the pressure.

[0017] Explanation of reference numerals in the attached figures: 100, Flexible substrate; 101, First surface; 102, Second surface; 200, Dielectric substrate layer; 300, Metal backplate; 400, Metal resonant unit; 410, First oscillator; 420, Second oscillator; 500, Protective layer; 600, Metasurface structure unit; R1, the outer radius of the first and second arc-shaped structures; R2, the inner radius of the first and second arc-shaped structures; G, the spacing between the first and second arc-shaped structures; W, the width of the first and second oscillators. Detailed Implementation

[0018] As described in the background section, miniaturization and long battery life of pressure sensors are technical problems that need to be solved.

[0019] To address the aforementioned technical problems, the present invention provides a pressure sensor based on an electromagnetic metasurface, along with its fabrication method and components. By setting a flexible substrate and a metal resonant structure, the resonant frequency is bound to the pressure, thereby achieving miniaturization and long battery life of the pressure sensor.

[0020] To make the above-mentioned objectives, features, and beneficial effects of the present invention more apparent and understandable, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. Additionally, directional terms such as above, below, up, down, upward, downward, left, right, etc., are used relative to exemplary embodiments as they are shown in the figures, with upward or upper directions pointing towards the top of the corresponding figure and downward or lower directions pointing towards the bottom of the corresponding figure.

[0022] Figures 1 to 4This is a schematic diagram of the structural steps in the fabrication method of a pressure sensor based on an electromagnetic metasurface according to an embodiment of the present invention. Wherein, Figure 3 This is a top view of the structure of the metal resonant unit of the pressure sensor according to an embodiment of the present invention.

[0023] Please refer to Figure 1 A flexible substrate 100 and a dielectric substrate layer 200 are provided. The flexible substrate 100 has a first surface 101 and a second surface 102 opposite to each other. The dielectric substrate layer 200 is bonded to the second surface 102 of the flexible substrate 100.

[0024] Specifically, the thickness of the flexible substrate 100 can be 0.2 mm to 0.6 mm.

[0025] Specifically, the material of the flexible substrate 100 may include at least one of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polydimethylsiloxane (PDMS), and polyurethane (PU).

[0026] Preferably, the flexible substrate 100 can be made of polydimethylsiloxane, and the thickness of the flexible substrate 100 can be 0.4 mm.

[0027] Specifically, the material of the dielectric substrate layer 200 may include at least one of polyimide (PI), modified polyimide (MPI), liquid crystal polymer (LCP), and polyester film (PET).

[0028] Specifically, the material of the dielectric substrate layer 200 may also include at least one of polytetrafluoroethylene (PTFE) substrate, hydrocarbon resin substrate, and high-performance epoxy resin fiberglass cloth substrate (high-performance FR-4).

[0029] Preferably, the material of the dielectric substrate layer 200 can be polyimide, and the thickness of the dielectric substrate layer 200 can be 50 μm.

[0030] In this embodiment, bonding the dielectric substrate layer 200 to the second surface 102 of the flexible substrate 100 may include forming an adhesive layer (not shown) between the dielectric substrate layer 200 and the second surface 102 of the flexible substrate 100 to bond the dielectric substrate layer 200 to the second surface 102 of the flexible substrate 100.

[0031] The adhesive layer can be made of UV (Ultraviolet) curing adhesive or low-temperature epoxy adhesive.

[0032] Specifically, the process of forming the adhesive layer may include pre-treating the second surface 102 of the dielectric substrate layer 200 and the flexible substrate 100, applying precision adhesive to the second surface 102 of the dielectric substrate layer 200 and the flexible substrate 100, and then bonding and aligning the second surface 102 of the dielectric substrate layer 200 and the flexible substrate 100 and curing them to form the adhesive layer.

[0033] In this embodiment, the thickness of the formed adhesive layer is less than 10 μm.

[0034] Please continue to refer to this. Figure 1 A metal backplate 300 is deposited on the first surface 101 of the flexible substrate 100.

[0035] Specifically, the thickness of the metal backing plate 300 can be 18μm to 35μm.

[0036] Specifically, the metal backplate 300 can be made of at least one of aluminum, copper, and silver.

[0037] Preferably, the material of the metal backing plate 300 can be copper, and the layer thickness of the metal backing plate 300 can be 35μm.

[0038] Please refer to Figure 2 Several metal resonant units 400 are formed on the surface of the dielectric substrate layer 200 away from the flexible substrate 100.

[0039] In this embodiment, the process for forming a plurality of metal resonant units 400 can be a stripping process.

[0040] In this embodiment, forming the dry metal resonant unit 400 may include: forming a patterned photoresist layer on the surface of the dielectric substrate layer 200 away from the flexible substrate 100; forming a metal layer (not shown) on the surface of the photoresist layer and the exposed surface of the dielectric substrate layer 200; and peeling off the photoresist layer and the metal layer on the photoresist layer to form a plurality of metal resonant units 400 located on the surface of the dielectric substrate layer 200.

[0041] Specifically, the layer thickness of the metal resonator unit 400 can be 18μm to 35μm.

[0042] Specifically, the material of the metal resonator 400 can be at least one of aluminum, copper, and silver.

[0043] Preferably, the material of the metal resonant unit 400 can be copper, and the layer thickness of the metal resonant unit 400 can be 20 μm.

[0044] In this embodiment, the metal resonant unit 400 is preferably disposed on the surface of the dielectric substrate layer 200, rather than directly on the surface of the flexible substrate 100. On the one hand, the high surface energy of the dielectric substrate layer 200 improves the processing accuracy and adhesion stability of the metal resonant unit 400; on the other hand, the dielectric substrate layer 200, as a support layer, can effectively suppress the lateral tensile deformation of the metal resonant unit 400 itself during pressure, ensuring that the resonant frequency shift is only affected by the change in interlayer distance, thereby significantly improving the linearity and measurement accuracy of the pressure sensor.

[0045] Please refer to Figure 3 The metal resonant unit 400 may include a first oscillator 410 and a second oscillator 420 that are orthogonal to each other.

[0046] The centers of the first oscillator 410 and the second oscillator 420 coincide.

[0047] In this embodiment, the first oscillator 410 has a first arc-shaped structure at both ends, and the second oscillator 420 has a second arc-shaped structure at both ends. The first arc-shaped structure and the second arc-shaped structure have the same center and are spaced apart from each other.

[0048] Specifically, the outer radius R1 of the first arc-shaped structure and the second arc-shaped structure can both be 1.7mm, the inner radius R2 of the first arc-shaped structure and the second arc-shaped structure can both be 1.3mm, the interval G between the first arc-shaped structure and the second arc-shaped structure can both be 0.2mm, and the width W of the first oscillator 410 and the second oscillator 420 can both be 0.3mm.

[0049] In this embodiment, the first oscillator 410 and the second oscillator 420 have 90° rotational symmetry in the plane, which makes them have equivalent electromagnetic coupling characteristics for mutually orthogonal electric field components. This makes the equivalent resonant modes excited by normally incident TE polarized and TM polarized electromagnetic waves consistent, and thus exhibits consistent electromagnetic response to orthogonal polarization.

[0050] Please refer to Figure 4 A protective layer 500 is formed covering the surface of several metal resonant units 400.

[0051] In this embodiment, the protective layer 500 is located on the surface of the metal resonant unit 400, and the metal resonant unit 400 is located between the dielectric substrate layer 200 and the protective layer 500.

[0052] In this embodiment, the relative permittivity of the protective layer 500 is less than or equal to 2.

[0053] Specifically, the material of the protective layer 500 can be at least one of polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), and perfluoroalkoxy resin (PFA).

[0054] Please continue to refer to this. Figure 4 The flexible substrate 100, the metal backplate 300, the dielectric substrate layer 200 and the metal resonant unit 400 constitute the metasurface structure unit 600.

[0055] In this embodiment, several metasurface structure units 600 are arranged periodically, and the periodic dimension of the metasurface structure unit 600 is smaller than half the wavelength of the pressure sensor at its operating frequency. In this embodiment, the several metasurface structure units 600 are arranged in a rectangular array.

[0056] Specifically, the period size can be understood as the distance from the center of one cell to the center of the adjacent cell in an array.

[0057] Specifically, half wavelength can be understood as half the length of the wavelength.

[0058] In this embodiment, the periodic dimension P of the metasurface structure unit 600 can be 4 mm.

[0059] Specifically, the flexible substrate 100 has a first surface 101 and a second surface 102.

[0060] Specifically, the metal backplate 300 is located on the first surface 101 of the flexible substrate 100. In the metal backplate 300, the surface opposite to the flexible substrate 100 is used to receive the measured pressure.

[0061] Specifically, the dielectric substrate layer 200 is located on the second side of the flexible substrate 100.

[0062] Specifically, the metal resonant unit 400 is located on the surface of the dielectric substrate layer 200 away from the flexible substrate 100.

[0063] Please refer to Figure 5 In this embodiment of the invention, as the pressure increases (0 kPa→75 kPa), the resonant frequency of the pressure sensor shifts to a lower frequency direction (15.815 GHz→15.61 GHz), the reflection coefficient decreases, and the absorption coefficient increases.

[0064] Please refer to Figure 6 In this embodiment of the invention, the resonant frequency of the pressure sensor exhibits an approximately linear change trend with increasing external pressure, and its linear correlation coefficient reaches 0.989. This indicates that the pressure sensor of this embodiment has good linear response characteristics to pressure changes and is suitable for pressure monitoring applications.

[0065] In this embodiment, the pressure sensor includes several periodically arranged metasurface structure units 600. The periodic dimension of the metasurface structure unit 600 is smaller than half the wavelength of the pressure sensor at its operating frequency. Therefore, the metasurface structure can "confine" the incident electromagnetic wave energy within the structure, forming a strong local surface field. This local field is extremely sensitive to changes in the surface environment. Even if the pressure only causes micron-level compression of the interlayer spacing (thickness of the flexible substrate 100), it will severely disturb this local field, thereby causing significant changes in the reflected electromagnetic wave and improving the detection accuracy of the pressure sensor. The metasurface structure unit 600 includes: a flexible substrate 100 having opposing first surfaces 101 and second surfaces 102; a metal backplate 300 located on the first surface 101 of the flexible substrate 100, wherein the surface of the metal backplate 300 opposite to the flexible substrate 100 is used to receive the measured pressure; a dielectric substrate layer 200 located on the second surface of the flexible substrate 100; and a metal resonant unit 400 located on the surface of the dielectric substrate layer 200 away from the flexible substrate 100. Therefore, when pressure is applied to the metal backplate 300, the flexible substrate 100 undergoes elastic deformation, resulting in a decrease in layer thickness and an increase in relative permittivity, causing a measurable shift in the resonant frequency generated by the metal resonant unit 400. Thus, the resonant frequency is bound to the pressure, thereby realizing the function of a pressure sensor. Since several metasurface structure units 600 realize the function of a pressure sensor, the pressure sensor of the present invention does not require a chip or a signal transceiver module, reducing the space occupied by the pressure sensor and thus realizing the miniaturization of the pressure sensor. Furthermore, since the pressure sensor is a passive response and does not contain energy storage components such as batteries, it is unaffected by battery life and charging frequency, thus achieving high endurance. Also, because the protective layer 500 is located on the surface of the metal resonant unit 400, which is situated between the dielectric substrate layer 200 and the protective layer 500, it provides support and protection for the metal resonant units 400, further improving the detection accuracy of the pressure sensor. The pressure sensor provided by this invention, by constructing several electromagnetic metasurface structures from the metal backplate 300, flexible substrate 100, dielectric substrate layer 200, and metal resonant units 400, directly maps pressure information into resonant frequency signals. In terms of hardware, it eliminates the need for signal conditioning chips, transceiver modules, and power supplies, achieving miniaturization and high endurance of the pressure sensor.

[0066] Accordingly, this invention also provides a pressure sensor based on an electromagnetic metasurface prepared by the above-described preparation method.

[0067] Please continue to refer to this. Figure 4 The pressure sensor based on the electromagnetic metasurface may include several periodically arranged metasurface structural units 600 and a protective layer 500.

[0068] Specifically, the periodic dimension of the metasurface structure unit 600 is smaller than half the wavelength of the pressure sensor at its operating frequency.

[0069] Specifically, the metasurface structure unit 600 may include: a flexible substrate 100, a metal backplate 300, a dielectric substrate layer 200, and a metal resonant unit 400.

[0070] Specifically, the flexible substrate 100 has a first surface 101 and a second surface 102.

[0071] Specifically, the metal backplate 300 is located on the first surface 101 of the flexible substrate 100. In the metal backplate 300, the surface opposite to the flexible substrate 100 is used to receive the measured pressure.

[0072] Specifically, the dielectric substrate layer 200 is located on the second side of the flexible substrate 100.

[0073] Specifically, the metal resonant unit 400 is located on the surface of the dielectric substrate layer 200 away from the flexible substrate 100.

[0074] Specifically, the protective layer 500 is located on the surface of the metal resonant unit 400, and the metal resonant unit 400 is located between the dielectric substrate layer 200 and the protective layer 500.

[0075] Accordingly, embodiments of the present invention also provide a pressure sensor assembly based on an electromagnetic metasurface, which may include a pressure sensor and an antenna prepared by the above-described preparation method.

[0076] Specifically, the antenna is used to transmit electromagnetic waves and to receive electromagnetic waves reflected by the pressure sensor.

[0077] Specifically, the materials, forming process, working principle, specific implementation method and beneficial effects of the pressure sensor based on electromagnetic metasurface and the pressure sensor component based on electromagnetic metasurface in the embodiments of the present invention can be found in the preparation method of the pressure sensor based on electromagnetic metasurface in the embodiments of the present invention, and will not be repeated here.

[0078] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A pressure sensor based on an electromagnetic metasurface, characterized in that, include: A plurality of periodically arranged metasurface structural units, wherein the periodic dimension of the metasurface structural units is smaller than half the wavelength of the pressure sensor at the operating frequency; The metasurface structure unit includes: a flexible substrate having a first side and a second side facing each other; a metal backplate located on the first side of the flexible substrate, wherein the surface of the metal backplate facing the flexible substrate is used to receive the measured pressure; a dielectric substrate layer located on the second side of the flexible substrate; and a metal resonant unit located on the surface of the dielectric substrate layer away from the flexible substrate. A protective layer is located on the surface of the metal resonant unit, which is located between the dielectric substrate layer and the protective layer.

2. The pressure sensor as described in claim 1, characterized in that, The thickness of the metal backing plate is 18μm to 35μm.

3. The pressure sensor as described in claim 2, characterized in that, The thickness of the flexible substrate is 0.2 mm to 0.6 mm.

4. The pressure sensor as described in claim 1, characterized in that, The metasurface structural units are arranged in a rectangular array.

5. The pressure sensor as described in claim 1, characterized in that, The thickness of the metal resonant unit is 18μm to 35μm.

6. The pressure sensor as described in claim 1, characterized in that, The metal resonant unit includes a first oscillator and a second oscillator that are orthogonal to each other, with the centers of the first oscillator and the second oscillator coinciding with each other.

7. The pressure sensor as described in claim 6, characterized in that, The first oscillator has a first arc-shaped structure at each end, and the second oscillator has a second arc-shaped structure at each end. The first arc-shaped structure and the second arc-shaped structure have the same center and are spaced apart from each other.

8. A method for fabricating a pressure sensor based on an electromagnetic metasurface, characterized in that, include: A flexible substrate and a dielectric substrate layer are provided, the flexible substrate having opposing first and second surfaces; The dielectric substrate layer is bonded to the second side of the flexible substrate; A metal backplate is deposited on the first surface of the flexible substrate; A plurality of metal resonant units are formed on the surface of the dielectric substrate layer away from the flexible substrate; A protective layer is formed covering the surface of several of the metal resonant units.

9. The preparation method according to claim 8, characterized in that, Forming a plurality of said metal resonant units includes: forming a patterned photoresist layer on the surface of the dielectric substrate layer away from the flexible substrate; forming a metal layer on the surface of the photoresist layer and the exposed surface of the dielectric substrate layer; and stripping away the photoresist layer and the metal layer on the photoresist layer to form a plurality of metal resonant units located on the surface of the dielectric substrate layer. The step of bonding the dielectric substrate layer to the second surface of the flexible substrate includes: forming an adhesive layer between the dielectric substrate layer and the second surface of the flexible substrate to bond the dielectric substrate layer to the second surface of the flexible substrate, wherein the thickness of the adhesive layer is less than 10 μm.

10. A pressure sensor assembly based on an electromagnetic metasurface, characterized in that, include: The pressure sensor as described in any one of claims 1 to 7; An antenna for transmitting electromagnetic waves and receiving electromagnetic waves reflected by the pressure sensor.

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