Pressure sensor with mixed structure, preparation method and application

Abstract

The invention discloses a pressure sensor based on a non-metal suspended structure-two-dimensional material-metal mixed structure, and the pressure sensor comprises a substrate structure which comprises a solid material substrate and a non-metal suspended structure located on the solid material substrate, and a cavity formed through etching is formed below the non-metal suspended structure; the pressure-sensitive layer is positioned on the non-metal suspended structure, is made of a single-layer or multi-layer conductive two-dimensional material and forms a pressure sensing functional area; the electrode layer is located on the pressure-sensitive layer, comprises at least two metal electrodes and is used for being connected with an external circuit and conducting electrical signals. The invention also discloses a preparation method and application of the pressure sensor. According to the invention, the excellent piezoresistive effect of the two-dimensional material is fully utilized, high-sensitivity pressure detection is realized on a planar microstructure, the size is small, the integration degree is high, and the application coverage is wide.

Description

Technical Field

[0001] This invention relates to the fields of microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS), and particularly to a pressure sensor that utilizes a non-metallic suspended microstructure to support conductive two-dimensional materials and reads electrical signals through metal electrodes, as well as the preparation method and usage method of the sensor. Background Technology

[0002] MEMS / NEMS sensors are widely used in automotive, medical, and aerospace fields due to their advantages such as miniaturization, low power consumption, and high sensitivity. Common types of existing pressure sensors include piezoresistive and capacitive types. Traditional silicon-based piezoresistive devices suffer from significant temperature drift, brittle fracture under overload, and limited sensitivity; furthermore, residual stress, defects, and thickness inhomogeneity in the thin film during micro / nano fabrication processes can lead to decreased device consistency. Two-dimensional materials (such as graphene and molybdenum disulfide) possess atomic-level thickness, excellent mechanical strength, and electrical properties sensitive to deformation and temperature, providing a material basis for achieving high-sensitivity, small-size, and highly integrated pressure detection.

[0003] However, reliably integrating two-dimensional materials into mass-producible suspended microstructures still faces many challenges, including: low-damage transfer and patterning of two-dimensional materials, efficient coupling of external pressure to strain in two-dimensional materials, and high-precision reading and temperature drift suppression of minute resistance changes by electrodes and measurement circuits. Therefore, it is necessary to propose a hybrid structure pressure sensor with a well-defined structure, feasible fabrication process, and scalability to multiple readout methods. Summary of the Invention

[0004] This invention aims to provide a pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure. It achieves the conversion of pressure to resistance (or impedance) change through a stacked structure of "substrate and cavity-non-metallic suspended structure-conductive two-dimensional material pressure-sensitive layer-metal electrode layer". It also provides a matching preparation process and usage and calibration method to improve sensitivity, structural toughness and temperature stability.

[0005] To address the aforementioned technical problems, embodiments of the present invention provide a pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure, comprising: Substrate Structure: The substrate structure consists of a solid material substrate and a non-metallic suspended structure thereon. A cavity is formed below the non-metallic suspended structure region, allowing the suspended structure to undergo controllable deformation under external pressure. The non-metallic suspended structure can be directly connected to the solid material substrate, or it can be connected through a transition layer (e.g., an oxide material such as silicon dioxide) to improve interface adhesion, stress matching, or process compatibility. Pressure-sensitive layer: The pressure-sensitive layer is located on the non-metallic suspended structure and is composed of one or more layers of conductive two-dimensional material, which bends synchronously with the non-metallic suspended structure. External pressure is transmitted to the non-metallic suspended structure through the encapsulation or mounting structure, causing it to bend / stretch / compress, which in turn generates strain in the two-dimensional material and causes changes in the carrier transport characteristics, so that the resistance value of the pressure-sensitive layer changes with the pressure, thereby realizing pressure sensing; Electrode layer: Located above the pressure-sensitive layer, including at least two metal electrodes. The electrode layer forms a stable electrical contact with the two-dimensional material pressure-sensitive layer, enabling the external measurement circuit to obtain the electrical response of the pressure-sensitive layer resistance (or impedance) as a function of pressure. The pressure-sensitive layer has the characteristic that its resistance changes with the pressure applied, thus enabling pressure sensing.

[0006] Furthermore, the electrode layer includes at least two non-contact, electrically extensible metal electrodes. One end or part of each metal electrode covers a two-dimensional conductive material, preferably in part or all of the overlapping area of ​​the non-metallic suspended structure and the two-dimensional material layer, to ensure that the strain caused by pressure mainly occurs within the effective electrical channel; the two electrodes are electrically connected by the two-dimensional material layer in whole or in part, forming a measurement channel.

[0007] Furthermore, based on at least two electrodes, the metal electrodes can be further extended to four metal electrodes, which are connected to the two-dimensional material piezoresistive layer to form four variable resistor arms of a Wheatstone bridge. The four electrodes can be arranged symmetrically or asymmetrically at the edges or corners of the two-dimensional material sensing functional area to obtain higher differential output, suppress common-mode noise, and reduce the influence of lead resistance.

[0008] Furthermore, the solid semiconductor material support layer has cavities to form a suspended structure; the non-metallic suspended structure can be in the form of a thin film, a cantilever beam, or a nanowire. Different forms correspond to different mechanical responses: thin films are suitable for achieving large-area uniform stress; cantilever beams are suitable for converting external loads into a high-strain zone at the beam root; nanowires are suitable for achieving higher frequency resonance and higher strain sensitivity.

[0009] Furthermore, the pressure-sensitive layer is obtained by growing on a metal catalyst substrate and then transferring it through chemical vapor deposition, or by preparing it directly by an in-situ method.

[0010] Furthermore, the number of layers in the conductive two-dimensional material of the pressure-sensitive layer can be a single atomic layer or a multi-atom layer; the multi-atom layer can be formed by stacking the same material or by stacking multiple materials. Preferably, the thickness of the single atomic layer is less than 2 nm, and the thickness of the multi-atom layer is less than 10 nm, so as to achieve a balance between sensitivity, mechanical strength and process stability.

[0011] Furthermore, the pressure-sensitive layer is patterned using photolithography and etching methods.

[0012] Furthermore, the metal electrode is a gold electrode, a platinum electrode, a copper electrode, or an aluminum electrode, and the thickness of the metal electrode is greater than 30 nm. The metal electrode is prepared by photolithography and thermal evaporation processes.

[0013] Accordingly, embodiments of the present invention also provide a method for preparing the above-mentioned pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure, comprising the following steps: S1: Substrate fabrication: A solid material substrate is formed by depositing a non-metallic material layer on the front side of the solid material substrate; a window pattern required for fabricating the non-metallic suspended structure is defined by photolithography on the back side and / or the front side of the solid material substrate structure, and a wet and / or dry etching process is used to etch the solid material substrate to the non-metallic layer and / or oxide barrier layer on the front side, forming a suspended layer defined by the non-metallic layer and the cavity below it; a cantilever beam or nanowire structure is obtained by photolithography and dry etching processes on the front side of the non-metallic layer.

[0014] S2: Transfer and Patterning: The two-dimensional material grown by chemical vapor deposition is completely transferred to the front side of the structure obtained in S1 using polymer-assisted wet transfer technology to cover the suspended area; then, the two-dimensional material is patterned by etching process to form a two-dimensional material sensing area aligned with the non-metallic suspended structure area. S3: Interface processing: After the two-dimensional material is transferred and patterned, the overlapping area with the defined electrode pattern can be processed by sputtering, evaporation or oxidation.

[0015] S4: Electrode fabrication: Electrode patterns are defined on patterned two-dimensional materials by photolithography, and then metal thin films are deposited using processes such as electron beam evaporation and / or thermal evaporation and / or magnetron sputtering. Finally, metal electrodes in contact with the two-dimensional materials are formed by lift-off or etching processes.

[0016] Accordingly, this embodiment of the invention also provides an application of the pressure sensor based on the above-mentioned non-metallic suspended structure-two-dimensional material-metal hybrid structure for compensating for temperature drift. A temperature-sensitive electrode is prepared on any side of the pressure sensor based on the non-metallic suspended structure-two-dimensional material-metal hybrid structure. The temperature-sensitive electrode is a resistance thermometer formed by a resistance wire connected to a metal electrode, or a thermocouple based on the Seebeck effect. The resistance thermometer is the preferred option in the sensor described in this claim. The temperature-sensitive electrode is not sensitive to the stress on the device. The temperature-sensitive electrode is used for measuring the ambient temperature and / or for temperature calibration and temperature drift compensation of the pressure sensor.

[0017] This invention provides a method for electrical reading, calibration, and temperature compensation under static stress and strain: the device is encapsulated in a housing that enables stress conduction and installed in the environment under test (M1); the resistance of the pressure-sensitive layer is measured in real time using DC and / or AC methods (M2), including the bridge method, phase-locked loop method, and two-electrode method; a calibration relationship of "pressure-resistance change" is established by changing the absolute pressure at constant temperature (M6); a relationship of "temperature-resistance drift" is established by changing the temperature at constant pressure, and real-time temperature drift calibration is performed by combining the "temperature-resistance" relationship of the temperature-sensitive resistor (M7).

[0018] This invention also provides a real-time measurement method under dynamic resonance: applying an AC excitation signal between any two electrodes to cause the device to oscillate near its intrinsic frequency and track the resonant frequency, damping or quality factor Q value; The applied signal can be Changes in external stress (or air pressure) cause alterations in the intrinsic frequency and / or damping and / or Q value. Real-time stress measurement can be achieved by combining these with pre-calibrated relationships. For resonant frequency offset monitoring, the temperature drift contribution can be separated using the temperature-sensitive resistor module of claim 9. For damping or Q value monitoring, temperature drift compensation can be reduced or eliminated when temperature sensitivity is low.

[0019] Compared with the prior art, the present invention has at least the following beneficial effects: (1) The external pressure is efficiently converted into controllable deformation through a non-metallic suspended structure and directly coupled to the two-dimensional material pressure-sensitive layer to achieve high-sensitivity pressure detection; (2) The two-dimensional material is extremely thin and can obtain significant resistance changes within a small size, which is conducive to miniaturization and array integration; (3) The electrode structure can be expanded into a Wheatstone bridge to achieve differential readout and suppress common-mode noise; (4) A calibration and compensation scheme with thermistor assistance is provided to improve temperature stability; (5) Two types of usage methods are provided: static resistance readout and dynamic resonance readout, which are suitable for different application scenarios. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a top view of the structure of the present invention; Figure 3 It is shown Figure 2 Schematic diagram of the cross-sectional structure of AA; Figure 4 This is a schematic diagram of the packaging structure of the present invention. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings. It should be understood that the following embodiments are only for explaining the present invention and are not intended to limit the scope of protection of the present invention; all equivalent substitutions or modifications made in accordance with the claims of the present invention should fall within the scope of protection of the present invention.

[0022] The first aspect of the present invention provides a pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure.

[0023] like Figures 1-3 As shown, the pressure sensor in this embodiment includes, from bottom to top, a substrate structure 1, a pressure-sensitive layer 2, and an electrode layer 3. The substrate structure 1 includes a solid material substrate 11 and a non-metallic suspended structure 12 located thereon, with a cavity 13 below the non-metallic suspended structure 12. The solid material substrate 11 can be a semiconductor or insulating material such as silicon, SOI, glass, ceramic, or gallium nitride, or it can be a polymer material with supporting capabilities; the non-metallic suspended structure 12 can be a non-metallic thin film or a composite layer of silicon nitride, silicon dioxide, silicon carbide, or alumina, and can be connected to the substrate through a transition layer to improve adhesion and stress matching.

[0024] The pressure-sensitive layer 2 is a single-layer or multi-layer conductive two-dimensional material (such as graphene, transition metal chalcogenides, or other two-dimensional conductive materials with piezoresistive effect), which covers the non-metallic suspended structure 12 and forms the sensing functional area. When external pressure is applied, the suspended structure 12 flexes and drives the two-dimensional material to bend synchronously, causing the two-dimensional material to produce tensile / compressive strain, resulting in a measurable change in its resistance (or impedance).

[0025] The electrode layer 3 includes at least two metal electrodes 31 (e.g., Au, Pt, Cu, Al, etc.). One end or part of the electrode covers the surface of the two-dimensional material and forms an electrical contact. The electrode lead-out end is used to connect to an external measurement circuit. The electrode coverage area is preferably located in the overlapping area of ​​the two-dimensional material and the suspended structure to ensure that the electrical channel is mainly located in the stress-sensitive area.

[0026] In a further embodiment, the electrode layer 3 includes four electrodes 31. These four electrodes, together with the two-dimensional material piezoresistive layer, form four variable resistor arms R1-R4 and are connected to form a Wheatstone bridge. After applying an excitation voltage Vin to the bridge, the piezoresistive response is obtained by acquiring the differential output Vout at the two midpoints of the bridge. This improves sensitivity and suppresses the common-mode effects caused by temperature or power supply fluctuations.

[0027] The second aspect of the present invention provides a method for preparing the above-mentioned pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure.

[0028] Step S1 (Substrate Preparation): A solid material substrate is selected as the mechanical support substrate. A non-metallic material layer is deposited on its front side to form the material layer for the future suspended structure. Subsequently, the window pattern required for forming the suspended structure is defined on the back side and / or the front side of the substrate by photolithography. The substrate is etched using wet and / or dry etching processes until the non-metallic layer and / or oxide barrier layer on the front side is reached, forming the suspended region covered by the non-metallic layer and the cavity below it. If necessary, the suspended structure such as cantilever beams or nanowires can be further obtained by photolithography and dry etching on the front side of the non-metallic layer.

[0029] Step S2 (2D Material Transfer and Patterning): The 2D material grown by chemical vapor deposition is transferred to the front side of the structure obtained in step S1 using a polymer-assisted wet transfer method, so that the 2D material covers the suspended area. Subsequently, the 2D material is patterned by photolithography and plasma etching to obtain a 2D material sensing area aligned with the non-metallic suspended structure area. For in-situ prepared 2D materials, the growth area can be defined by photolithography first, and then a 2D material layer can be formed by processes such as evaporation, magnetron sputtering, chemical vapor deposition, transfer or bonding. Finally, the aligned 2D material sensing area is obtained by peeling and / or etching.

[0030] Step S3 (Interface Treatment): After the two-dimensional material is transferred and patterned, the interface treatment is performed on the overlapping area of ​​the two-dimensional material and the metal electrode to adjust the contact resistance and / or improve the surface smoothness. The interface treatment may include one or more processes such as sputtering, evaporation, oxidation, metallization, or deposition of an oxide layer.

[0031] Step S4 (Electrode fabrication): Electrode patterns are defined on the two-dimensional material by photolithography, and metal thin films are deposited by electron beam evaporation and / or thermal evaporation and / or magnetron sputtering. Metal electrodes in contact with the two-dimensional material are formed by peeling or etching.

[0032] The third aspect of this invention provides an application of the pressure sensor based on the non-metallic suspended structure-two-dimensional material-metal hybrid structure for compensating for temperature drift. A temperature-sensitive electrode is fabricated at a certain distance from either side of the pressure sensor based on the non-metallic suspended structure-two-dimensional material-metal hybrid structure. This electrode is typically a resistance temperature detector (RTD) formed by a resistance wire connected to a metal electrode, or a thermocouple based on the Seebeck effect. The RTD is preferred in the sensor described in this claim. The temperature-sensitive electrode is insensitive to the stress applied to the device and is used for measuring ambient temperature and / or for temperature calibration and temperature drift compensation of the pressure sensor.

[0033] The distance described above can be limited to 200 micrometers greater than the edge of the non-metallic suspended structure, but not exceeding the size of the substrate of the device itself. The aforementioned thermal resistor, such as a Pt electrode, is the preferred option.

[0034] The temperature-sensitive electrode is bonded to its two ends with leads, and the resistance is sensed by the external circuit. In the case of a thermocouple, the external circuit will sense the voltage difference caused by the Seebeck effect. The device extracts the resistance change (or voltage change if it is a thermocouple) and correlates it with the temperature change. Simultaneously, the temperature change is used to adjust the input control voltage of the sensor described in this invention to stabilize the operating temperature, thus compensating for parameter changes caused by ambient temperature drift.

[0035] like Figure 4 As shown, the present invention can employ a solid-state rigid connection, with the sensor encapsulated in a housing that enables stress transmission, and the device installed in the environment under test.

[0036] (a) Thermistor setting: A thermistor is set near the sensor body. Its placement and mechanical connection method prevent it from undergoing significant stress changes with external pressure, so that its resistance change mainly reflects the ambient temperature. The thermistor can be composed of a resistance wire / resistance strip made of metal materials such as Pt and its lead electrodes, and is connected to an external temperature measuring circuit.

[0037] (II) Static Measurement: The device is encapsulated in a housing that enables stress transmission and installed in the environment under test. Real-time measurement of the piezoresistive layer resistance can be achieved using: 1) Wheatstone Bridge Method: The two-dimensional material resistor is used as the sensitive arm of a Wheatstone bridge (the other arms are precision resistors or adjustable resistors with matching resistance values). A constant DC voltage, constant DC current, or AC excitation is applied, and the differential output of the bridge is collected as the pressure response. The differential output voltage at the two midpoints of the bridge is collected as the piezoresistive response signal, thereby achieving real-time pressure measurement. 2) Phase-locked loop (PLL) method: Apply an AC or AC + DC signal to a pair of electrodes and simultaneously use the synchronous trigger signal of the AC signal as the PLL reference signal; use at least another pair of electrodes to collect the voltage divider signal generated by the two-dimensional material sensitive layer under the AC or AC + DC voltage signal, and perform phase-sensitive detection to obtain the amplitude and phase information with the same frequency as the reference signal, thereby realizing high-precision reading of the resistance (or impedance) change of the two-dimensional material sensitive layer; 3) Two-electrode method: Apply a test signal to the electrodes, which can be a DC constant voltage, a DC constant current, or an AC small signal. During the test, collect the voltage and current between the two electrodes and calculate the resistance change of the two-dimensional material sensitive layer.

[0038] (III) Pressure calibration: Place the device in a controllable absolute pressure environment and keep the temperature constant, change the absolute pressure and record the output of the measuring device, calculate the change in the resistance of the pressure-sensitive layer, and establish a "pressure-resistance change" calibration curve.

[0039] (iv) Temperature Calibration and Compensation: The device is placed in a controllable absolute pressure and temperature environment. The pressure is stabilized while the absolute temperature is changed. During this process, the amplitude and / or phase information output by the lock-in amplifier and / or high-precision multimeter and / or other precision measuring equipment connected to the metal electrode of the pressure sensor are recorded, and the change in resistance is calculated accordingly to obtain the "temperature-resistance drift" relationship. Simultaneously, the amplitude and / or phase information obtained by measuring the on-chip thermistor and / or electrode using the lock-in amplifier and / or high-precision multimeter and / or other precision measuring equipment is recorded. Using the "temperature-resistance" relationship of the thermistor, combined with the sensor's "temperature-resistance drift" calibration information, the temperature drift of the pressure sensor based on the non-metallic suspended structure-two-dimensional material-metal hybrid structure is calibrated in real time.

[0040] (V) Dynamic Resonance Measurement: The resistance of the piezoresistive layer is measured in real time (under dynamic resonance) using DC and / or AC methods. For the resonance method, an excitation signal is introduced between any two electrodes. The excitation signal can be an AC sine wave, square wave, triangular wave, or other possible periodic function signal that can excite the mechanical vibration of the resonator. Excitation is achieved near the intrinsic frequency of the sensor, and the resonant frequency and / or resonant mode damping (damping: the half-width at half maximum corresponding to the frequency-amplitude relationship; or the ratio of the intrinsic frequency to it, i.e., the quality factor Q) are tracked through the peripheral circuit. After the sensor senses a change in external stress (or air pressure), the intrinsic frequency and / or damping and / or quality factor of the device change. Combined with the stress-intrinsic frequency and / or stress-damping and / or stress quality factor relationship calibrated by the device, the stress is measured in real time.

[0041] Pressure sensor resonance can be achieved by applying an AC signal at a frequency corresponding to the frequency of any of its resonant modes to any two or more electrodes. The frequency of the AC signal can typically be 1 / 2, 1, or 2 times the value of the intrinsic frequency corresponding to any resonant mode.

[0042] For a 1 / 2 frequency harmonic excitation, the AC signal can be set as: V = V DC + V AC V DC For the DC component, V AC For the AC component, it provides the system with a second harmonic AC component of the thermal response and a certain frequency bias, where V DC Positive or negative voltage is acceptable, or it can be set to 0V.

[0043] For a 1x frequency excitation, the AC signal typically needs to be set as: V = V DC + V AC , where V AC The AC component provides the system with a second harmonic AC component of the thermal response and a certain frequency offset; simultaneously, VDC Provides the resonant frequency offset and V to the system AC Together, they provide the first harmonic AC component for the system's thermal response; the resonant system is excited by the first harmonic AC component. For the device involved in this invention, due to the special relationship between the two materials and the metal interface, the first harmonic signal (V...)... AC Under the incentive, V DC It can be set to 0 V. In this system, V AC This will directly generate the first harmonic component of the system's thermal response, achieving excitation. The resonator's dynamic state is a combination of resonance and parametric excitation. In this mode, even if V DC Even at 0V, a very efficient excitation level can be achieved, which can directly excite the resonant system to a nonlinear vibration state, fully meeting the excitation intensity required by the dynamic range of conventional linear resonant excitation.

[0044] The resonant oscillation frequency is near the eigenfrequency of any of the excited resonant modes, and the resonant operating state of the pressure sensor is monitored at this frequency.

[0045] When resonant frequency shift is used as the monitoring quantity, the frequency shift caused by temperature drift can be separated and compensated by combining the output of the thermistor; when damping or Q value is used as the monitoring quantity and is not sensitive to temperature, the temperature drift calibration steps can be reduced.

[0046] Without altering the structure defined in the preceding claims, a further implementation of differential temperature drift compensation can be provided: a "sensing resonator" and a "reference resonator" are disposed within the same chip or package. Both have identical material stack-up structures and geometric dimensions, and are located in the same temperature field. The sensing resonator is exposed to the measured physical field (e.g., pressure / stress) and generates a frequency change caused by both temperature and pressure. The reference resonator is located outside the measured physical field through package shielding or mechanical decoupling, and its frequency change only includes temperature effects. Differential calculation of the frequency changes of both yields a pure pressure signal, achieving classic and effective temperature drift compensation. This differential method does not rely on real-time temperature measurement by the thermistor, but the addition of the reference resonator and corresponding package structure increases device area and packaging cost.

[0047] By applying real-time adjusted DC and / or AC voltages to any two electrodes of the pressure sensor, the operating point temperature of the device can be stabilized and / or adjusted, thereby precisely controlling the operating point frequency of the pressure sensor; combined with the ambient temperature information provided by the thermistor, the intensity of the applied DC and / or AC voltages is controlled to achieve temperature drift control.

[0048] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure, characterized in that, include: Substrate structure: includes a solid material substrate and a non-metallic suspended structure thereon, wherein a cavity is formed by etching below the non-metallic suspended structure region, and the non-metallic suspended structure is directly connected to the solid material substrate or connected through a transition layer; Pressure-sensitive layer: Located on the non-metallic suspended structure, it is a single or multiple layers of conductive two-dimensional material forming the sensing functional area, and it bends synchronously with the non-metallic suspended structure. Electrode layer: Located above the pressure-sensitive layer, used for connecting to external circuits and conducting electrical signals; The pressure-sensitive layer has the characteristic that its resistance changes with the pressure applied, thus enabling pressure sensing.

2. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 1, characterized in that, The electrode layer includes at least two non-contact, electrically extruded metal electrodes. One end or part of each metal electrode covers the two-dimensional conductive material. This area should be part or all of the overlapping area between the non-metallic suspended structure and the two-dimensional material layer. At the same time, the two electrodes should be electrically connected by the two-dimensional material layer in whole or in part.

3. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 1, characterized in that, The solid semiconductor material support layer has cavities to form a suspended structure, and the non-metallic suspended structure includes one of a thin film, a cantilever beam, and a nanowire.

4. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 2, wherein the plurality of metal electrodes can be any four metal electrodes connected to the two-dimensional material pressure-sensitive layer to form four variable resistance arms of a Wheatstone bridge, and the four metal electrodes are arranged symmetrically or asymmetrically at the edge or corner of the two-dimensional material sensing functional area.

5. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 1, characterized in that, The pressure-sensitive layer is a conductive two-dimensional material with one or more atomic layers.

6. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 5, characterized in that, The multi-atom layer includes a multi-atom layer composed of a single material or a multi-atom layer formed by stacking multiple materials.

7. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 6, characterized in that, The pressure-sensitive layer is a conductive two-dimensional material with a single atomic layer and a thickness of less than 2 nm.

8. The pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure according to claim 6, characterized in that, The pressure-sensitive layer is a conductive two-dimensional material with one or more atomic layers, wherein the thickness of the single atomic layer is less than 2 nm and the thickness of the multi-atom layer is less than 10 nm.

9. A method for preparing a pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: Substrate preparation: Solid material substrate, depositing a non-metallic material layer on the front side of the solid material substrate; The window pattern required for fabricating the non-metallic suspended structure is defined by photolithography on the back and / or front of the solid material substrate structure, and wet and / or dry etching processes are used to etch the solid material substrate to the non-metallic layer and / or oxide barrier layer on the front, forming a suspended layer defined by the non-metallic layer and the cavity below it. Cantilever beams or nanowire structures are obtained by using photolithography and dry etching processes on the front side of the non-metallic layer. S2: Transfer and Patterning: The two-dimensional material grown by chemical vapor deposition is completely transferred to the front side of the structure obtained in S1 using polymer-assisted wet transfer technology to cover the suspended area; then, the two-dimensional material is patterned by etching process to form a two-dimensional material sensing area aligned with the non-metallic suspended structure area. S3: Interface processing: After the two-dimensional material is transferred and patterned, the overlapping area with the defined electrode pattern can be processed by sputtering, evaporation or oxidation. S4: Electrode fabrication: Electrode patterns are defined on patterned two-dimensional materials by photolithography, and then metal thin films are deposited by electron beam evaporation and / or thermal evaporation and / or magnetron sputtering processes. Finally, metal electrodes in contact with the two-dimensional materials are formed by lift-off or etching processes.

10. A pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure as described in any one of claims 1-8, used for compensating for temperature drift, characterized in that: A temperature-sensitive electrode is fabricated on any side of the pressure sensor based on a non-metallic suspended structure-two-dimensional material-metal hybrid structure. The temperature-sensitive electrode is a resistance thermometer formed by a resistance wire connected to a metal electrode, or a thermocouple based on the Seebeck effect. The resistance thermometer is the preferred option in the sensor described in this claim. The temperature-sensitive electrode is not sensitive to the stress on the device. The temperature-sensitive electrode is used for measuring the ambient temperature and / or for temperature calibration and temperature drift compensation of the pressure sensor.

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