A high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure

Abstract

A high differential pressure sensitivity dual-diaphragm resonant pressure sensor based on a lever structure is disclosed, relating to a pressure sensor. A lever transmission structure utilizing amplified lateral displacement is proposed. The sensor employs electrostatically excited piezoresistive detection and includes upper and lower pressure-sensing diaphragm layers, upper and lower glass layers, a structural layer, a substrate layer, and a lever layer. The pressure-sensing layer, substrate layer, and structural layer are made of silicon material, while the substrate layer is made of BF33 borosilicate glass. The pressure-sensing layer primarily bears the load pressure. When subjected to load pressure, the pressure diaphragm deforms, causing displacement of the silicon islands on the pressure-sensing diaphragm. These silicon islands, connected by a lever structure, amplify and transmit the lateral displacement to the resonator layer, thereby generating axial internal stress in the resonant beam on the resonator layer. This change in the resonator's resonant frequency characterizes the pressure. The glass layer serves as an encapsulation layer, forming a high-vacuum sealed cavity.

Description

Technical Field

[0001] This invention relates to a pressure sensor, and more particularly to a silicon-based resonant pressure sensor and its fabrication method based on a lever structure that amplifies the lateral displacement of the pressure membrane deformation and transmits it to the sensing mechanism. Background Technology

[0002] Since the early 1980s, MEMS (Micro-Electro-Mechanical Systems) resonant pressure sensors have gradually become one of the key technologies in pressure measurement. Supported by MEMS technology, these sensors have achieved miniaturization, high precision, and low cost. However, with the continuous expansion of application areas, the application of pressure sensors in extreme environments has attracted much attention, especially in high-end equipment, military weapons, aerospace, and deep-sea exploration. In these extreme environments, the detection of high hydrostatic pressure and differential pressure has become a significant technical challenge for MEMS pressure sensors.

[0003] MEMS pressure sensors can be categorized into differential pressure, absolute pressure, and gauge pressure types based on the reference pressure used for testing. Their core sensing mechanisms include piezoresistive, piezoelectric, and resonant types. Resonant pressure sensors are highly favored in pressure measurement due to their high accuracy, high sensitivity, and stability, achieving an overall accuracy better than 0.01%FS. However, for differential pressure sensors, balancing the detection of minute differential pressures under high static pressure conditions presents a significant technical challenge. Improving the sensitivity of differential pressure sensors is therefore crucial for enhancing overall performance.

[0004] Many companies and research teams, both domestically and internationally, have begun developing related products. Foreign companies such as Druck, YOKOGAWA, Paroscientific, and Thales started developing such products as early as the 1980s. Domestic research institutions and universities, such as the Institute of Electronics of the Chinese Academy of Sciences, Beijing University of Aeronautics and Astronautics, University of Electronic Science and Technology of China, Xiamen University, and Northwestern Polytechnical University, began their research in this field in the 1990s. Summary of the Invention

[0005] The purpose of this invention is to solve the problem of detecting minute differential pressure under high hydrostatic pressure conditions by providing a high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure. This invention is based on the lever principle, amplifying the minute displacement caused by differential pressure, thereby improving the sensor's sensitivity. By using a resonant beam as the sensing element, the change in its natural frequency reflects the pressure change. It can operate under high pressure environments and possesses high measurement accuracy and stability.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure comprises, from bottom to top, a lower pressure-sensing layer, a lower glass layer, a lever layer, a lower substrate layer, an upper substrate layer, a structural layer, an upper glass layer, and an upper pressure-sensing layer;

[0008] The upper pressure-sensitive layer, lower pressure-sensitive layer, upper substrate layer, lower substrate layer, and structural layer are all made of silicon material, and the substrate layer is made of BF33 borosilicate glass. The upper and lower pressure-sensitive layers are used to bear load pressure. When bearing load pressure, the pressure diaphragm deforms, thereby causing the mass blocks of other layers to deflect. The mass blocks of each layer amplify the lateral displacement and transmit it to the structural layer through the lever layer and the lever structure connecting the upper and lower substrate layers. This causes the resonant beam on the structural layer to generate axial internal stress, causing the resonant frequency of the resonator to change, thereby characterizing the pressure. The upper and lower glass layers serve as encapsulation layers to form a high-vacuum sealed cavity.

[0009] The upper pressure-sensitive layer includes an upper pressure-sensitive membrane and four electrode holes, and the lower pressure-sensitive layer includes a lower pressure-sensitive membrane. The upper pressure-sensitive membrane is located on one side of the upper pressure-sensitive layer, and the lower pressure-sensitive membrane is located on one side of the lower pressure-sensitive layer, forming a reverse symmetrical distribution. The upper and lower pressure-sensitive membranes transmit the detected pressure deformation to the cover plates of each layer of the sensor structure. The upper and lower pressure-sensitive membranes are symmetrically distributed, and the four electrode holes are located around the upper pressure-sensitive layer.

[0010] The structural layer includes a resonant main beam, a resonant secondary beam, a mass block, a lever cover plate, a fixed drive tooth, a drive electrode, a movable resonant tooth, a detection piezoresistive beam, a detection electrode, and a ground electrode. The resonant main beam and the resonant secondary beam are interconnected. The movable resonant tooth is integral with the resonant secondary beam and connected to the resonant main beam. The fixed drive tooth is connected to the drive electrode. The resonant secondary beam is connected to the piezoresistive detection beam and the ground electrode at its end. One end of the resonant main beam is connected to the lever cover plate, and the other end is connected to the resonator mass block. The mass block is located at the center of the resonator, and only one end of the mass block is connected to the lever cover plate, while the other end is not fixed. The lever cover plates are symmetrically distributed and connected to the resonator. The detection piezoresistive beams are symmetrically distributed and connected, and all are connected to the detection electrode.

[0011] Both the upper and lower glass layers are made of BF33 borosilicate glass. The upper glass layer has a device groove corresponding to the lever layer in the center, and the lower glass layer has electrode holes corresponding to the four electrodes of the resonant layer and release grooves for the movable structure of the resonant layer.

[0012] The lever layer includes a lever cover plate, a lever support beam, and a lever transmission anchor point.

[0013] The upper substrate layer includes a substrate support lever cover plate, a substrate lever transfer block, and a substrate movable structure release groove; the lower substrate layer includes a lever support beam substrate groove and a substrate lever support beam anchor point.

[0014] The pressure-sensitive membrane is rectangular or rectangular in shape.

[0015] The upper pressure-sensitive layer and the lower pressure-sensitive layer are symmetrically distributed on both sides of the upper glass layer and the lower glass layer.

[0016] The resonant main beam, resonant secondary beam, and detection piezoresistive strip are all symmetrically distributed on both sides of the resonator.

[0017] The two ends of the resonant main beam are connected to the lever cover plate and the mass block, respectively. The mass block is connected to the lever cover plate on only one side, and there is no fixed resonator structure similar to a single-end fixed support on the other side.

[0018] The electrode holes are four in number, evenly distributed on the upper pressure-sensitive layer and the upper glass layer, and correspond to the positions of the electrodes such as the detection and driving electrodes of the resonant layer.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1) Enhanced sensitivity: The lever structure can amplify the small displacement of the sensor, thereby improving the sensor's sensitivity to pressure changes and enabling it to detect even smaller pressure changes.

[0021] 2) Improve resolution: By amplifying the lateral displacement, the sensor can convert minute pressure changes into larger displacement changes, thereby improving the sensor's resolution and enabling it to measure pressure more accurately.

[0022] 3) Enhanced stability: The lever structure can be adjusted by design to reduce the interference of the sensor with the external environment, thereby improving the stability and reliability of the sensor and enabling it to maintain accurate measurement results even in complex environments.

[0023] 4) Wide range of applications: It can be applied to industrial control, aerospace, automotive engineering and any other occasions that require high-precision pressure measurement. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention.

[0025] Figure 2 This is an exploded view of the three-layer structure according to an embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the overall lever portion according to an embodiment of the present invention.

[0027] Figure 4 This is a front view of the overall structure of the resonant layer according to an embodiment of the present invention.

[0028] Figure 5 This is a front view of the overall structure of the lever layer according to an embodiment of the present invention.

[0029] Figure 6This is a front view of the overall structure of the second substrate layer in an embodiment of the present invention.

[0030] Figure 7 This is a front view of the overall structure of the first substrate layer in an embodiment of the present invention.

[0031] Figure 8 This is a front view of the overall structure of the first glass layer in an embodiment of the present invention.

[0032] Figure 9 This is a front view of the overall structure of the second glass layer in an embodiment of the present invention.

[0033] Figure 10 This is a front view of the overall structure of the first pressure-sensitive layer in an embodiment of the present invention.

[0034] Figure 11 This is a front view of the overall structure of the second pressure-sensitive layer in an embodiment of the present invention.

[0035] Figure 12 This is a working cloud diagram of the lever differential pressure sensor.

[0036] Figure 13 This is a schematic diagram of the working modes of the structural layer.

[0037] Figure 14 The stress variation transmitted to the resonant main beam of the structural layer (original image of COMSOL simulation data).

[0038] exist Figures 1-11 In the middle, each is marked as:

[0039] 1. Electrode hole; 2. First pressure-sensitive membrane; 3. First pressure-sensitive layer; 4. Second pressure-sensitive layer; 5. First glass layer; 6. Second glass layer; 7. Structural layer; 8. First substrate layer; 9. Second substrate layer; 10. Lever layer; 11. Resonant main beam; 12. Resonant secondary beam; 13. Structural layer mass block; 14. Structural layer support lever cover plate; 15. Driving electrode; 16. Grounding electrode; 17. Detection piezoresistive beam; 18. Detection electrode; 19. Lever cover plate; 2 0. Lever support beam; 21. Lever transmission anchor point; 22. Lever support beam substrate groove; 23. Substrate layer lever support beam anchor point; 24. Substrate support lever cover plate; 25. Substrate layer lever transmission block; 26. Substrate layer movable structure release groove; 27. Glass layer electrode hole; 28. Glass layer movable structure release groove; 29. ​​Glass layer support lever cover plate; 30. Glass layer lever support beam groove; 31. Glass layer lever support anchor point; 32. Second pressure-sensitive membrane. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the following embodiments will be used in conjunction with the accompanying drawings to further illustrate the invention. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0041] See Figures 1-11 The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure includes a first pressure-sensing layer 3 and a second pressure-sensing layer 4, which respectively support the first pressure-sensing membrane 2 and the second pressure-sensing membrane 32 to sense changes in external pressure. These pressure-sensing membranes are symmetrically distributed on the pressure-sensing layers. When the external pressure changes, they deform, causing stress changes within the structural layers and affecting the working state of the driving detection electrodes. The structural layer 7 is located on the first pressure-sensing layer 3 and contains electrode holes for distributing the driving detection electrodes. The first glass layer 5 and the second glass layer 6 are anodicly bonded to the first pressure-sensing layer 3 and the second pressure-sensing layer 4, respectively. They not only provide mechanical support and protect the internal sensitive structure but also fix and support movable structures such as the resonant beam and lead out the electrode leads through the electrode holes. The glass layer support lever cover plates 29 are symmetrically distributed, providing mechanical support and protection for the support levers to ensure the stability and reliability of the sensor. The movable structure release groove 28 of the glass layer is located on the first glass layer 5, facing the movable structures such as the resonant beam in the structural layer, allowing the movable structures to move freely when deformed under pressure, thereby accurately transmitting pressure change signals. The glass layer electrode hole 27 is located on the first glass layer 5, directly opposite the electrode position in the structural layer 7, and is used for the lead-out of the electrode wire. Through the reasonable layout of the above components and the anode bonding, a high differential pressure sensitivity dual-film resonant pressure sensor is formed, which ensures the effective sensing of pressure changes and transmits signals through electrodes, enabling the sensor to accurately and sensitively detect and transmit pressure change information.

[0042] The structural layer 7 is connected to the second glass layer 6 via anodic bonding. Glass electrode holes 27, matching the electrodes at each end of the structural layer 7, are distributed on the second glass layer 6. These electrode holes 27 are connected to electrode holes 1 on the first pressure-sensitive layer 3, leading out electrode leads to achieve corresponding driving and detection. The second glass layer 6 is also connected to the lever layer 10 via anodic bonding. The lever cover plate 19 on the lever layer 10 is supported by the glass support lever cover plate 29 on the second glass layer 6. One side of the lever support beam 20 on the lever layer 10 is redundantly connected to the glass lever support beam groove 30 on the second glass layer 6, while the other side is redundantly connected to the substrate lever support beam groove 22 on the second substrate layer 9 via silicon-silicon bonding.

[0043] The lever support beam 20 and lever transfer anchor point 21 on the lever layer 10 are respectively connected to the glass layer lever support anchor point 31 on the second glass layer 6, the lever transfer block 25 on the second substrate layer 9, and the substrate layer lever support beam anchor point 23, thereby effectively transferring stress. The first substrate layer 8 and the second substrate layer 9 are connected by silicon-silicon bonding, providing support and reinforcement. The substrate layer lever transfer block 25 spans across the first substrate layer 8 and the second substrate layer 9, serving to lengthen the lever arm and transfer stress.

[0044] See Figure 3 The specific implementation scheme of the lever transmission effect is jointly completed by the lever layer 10 and the two substrate layers (first substrate layer 8 and second substrate layer 9). When the first pressure-sensitive membrane 2 and the second pressure-sensitive membrane 32 on the first pressure-sensitive layer 3 and the second pressure-sensitive layer 4 are deformed by external pressure, the stress is transmitted to the lever cover plate 19 of each layer structure. Rotational displacement is generated by the lever cover plate 19 on the lever layer 10 and the structural layer support lever cover plate 14 on the structural layer 7, driven by the first pressure-sensitive layer 3 and the glass layer support lever cover plate 29. This rotational displacement is amplified by the lever arm formed by the lever transmission block and lever transmission anchor point 21 of the lever layer 10, which connects the first substrate layer 8, the second substrate layer 9 and the lever transmission layer 10, thereby improving the differential pressure sensitivity of the sensor.

[0045] Through the rational layout and precise connection of the above components, a dual-film resonant pressure sensor with high differential pressure sensitivity was designed, ensuring effective sensing of pressure changes and accurate signal transmission. See also Figure 4The structural layer 7 is the core part of the sensor, containing key components such as a resonant beam. The structural layer 7 is connected to the second glass layer 6 by anodic bonding and is connected to the electrode holes on the first pressure-sensitive layer through electrode holes to achieve signal transmission. Specifically, the structural layer 7 is provided with a structural layer lever cover plate 14, a driving electrode 15, a grounding shell 16, a detection electrode 18, a resonant main beam 11, a resonant secondary beam 12, a structural layer mass block 13, and a detection piezoresistive strip 17. The driving electrode 15, grounding electrode 16, detection electrode 18, resonant main beam 11, resonant secondary beam 12, and detection piezoresistive beam 17 are symmetrically distributed in the resonant sensitive structure. The resonant secondary beam 12 is connected to the resonant main beam 11. The resonant main beam 11 is connected to the structural layer lever cover plate 14 through a resonant beam fixing anchor point for single-end fixed support. The resonant main beam 11 is connected to the structural layer mass block 13 on the resonant sensitive structure through a folded beam anchor point to form a folded beam structure. The bottom of the resonant secondary beam 12 is connected to the detection piezoresistive beam 17. The driving electrode 15 is used to apply an excitation signal to cause the resonant beam to vibrate, and the vibration of the main and secondary resonant beams is driven by the change in capacitance. The grounding housing 16 provides an electrical grounding path for the entire sensor, ensuring the safe operation of the circuit and shielding external electromagnetic interference. The detection electrode 18 is used to detect changes in the resonant frequency. When the resonant beam changes its natural frequency due to pressure changes, the detection electrode can capture this change, thereby indirectly measuring the pressure.

[0046] When the pressure changes, the shapes of the resonant main beam 11 and the resonant secondary beam 12 change accordingly. When the resonant main beam 11 vibrates, it drives the resonant secondary beam 12 to vibrate. The resonant secondary beam 12 vibrates in-plane around the bottom support point, which drives the detection piezoresistive beam 17 connected to the resonant secondary beam 12 to vibrate. The detection piezoresistive beam 17 is continuously subjected to compression and tension, causing its resistance value to change periodically. Under this condition, the natural frequencies of the resonant main beam 11 and the resonant secondary beam 12 decrease as the pressure increases, and the vibration frequency of the detection piezoresistive beam 17 decreases accordingly. The periodic change frequency of the resistance value also decreases. By detecting the change in electrical quantity generated by the change in the resistance value of the piezoresistive beam 17, the corresponding resonant frequency can be obtained.

[0047] The first glass layer 5 and the structural layer 7 are connected by bonding. A movable structure release groove 28 is provided on the bonding surface between the first glass layer 5 and the structural layer 7. The movable structure release groove 28 is used to allow the resonant main beam 11, the resonant secondary beam 12, and the detection piezoresistive beam 17 on the structural layer 7 to have space for free vibration.

[0048] The first pressure-sensitive layer 3 and the first glass layer 5 are connected by anodic bonding. An electrode through-hole 1 is opened on the first pressure-sensitive layer 3, and the electrode through-hole 1 is connected to the structural layer 7 through a glass layer electrode hole 27 on the first glass layer 5. When the sensor is working, an AC drive signal is required, and a periodic AC drive is applied to the drive electrode 15 through a network analyzer. An externally matched Wheatstone bridge circuit board is connected, and the ground electrode 16 and the circuit board are grounded together to the negative terminal of the DC power supply that powers the circuit board. The detection electrode 18 is connected back to the frequency signal output by the network analyzer.

[0049] The first pressure-sensitive membrane 2 and the second pressure-sensitive membrane 32 have a certain thickness and are rectangular in shape. The rectangular shape helps to evenly distribute pressure, thereby improving the accuracy and stability of the measurement, and is easy to manufacture and process, which is beneficial for improving production efficiency and reducing costs. The thickness of the first pressure-sensitive membrane 2 and the second pressure-sensitive membrane 32 can be adjusted within the allowable range of the process according to the measurement range and sensitivity requirements. Thicker pressure-sensitive membranes are suitable for withstanding higher pressures, but may reduce the sensitivity of the sensor because they require greater pressure to produce displacement. Conversely, thinner membranes may be more sensitive to lower pressures, but may be more easily damaged, especially in high-pressure environments. This embodiment of the invention can detect pressures up to 120 MPa with a membrane thickness of 300 μm.

[0050] The working principle and performance of the lever differential pressure sensor of the present invention are further analyzed below:

[0051] Differential pressure amplification: The modal cloud diagram of the lever differential pressure sensor of this invention during operation is shown below. Figure 12 As shown, Figure 12 This demonstrates how differential pressure applied to the sensor causes lateral displacement of the resonant main beam in the structural layer. The magnitude of this lateral displacement transmitted to the structural layer by the differential pressure can be amplified; the contour plot shows a 20-fold magnification of the rigid structure. Because this displacement is amplified 20 times, it can be inferred that the sensor has high sensitivity. This amplification effect is beneficial for improving the sensor's detection limit.

[0052] Response of the resonant main beam: The structural layer requires the resonant main beam 11 to achieve a certain frequency output under differential pressure conditions. When the external pressure changes, stress is transmitted to the resonant main beam of the structural layer, causing a change in the stiffness of the main beam, such as... Figure 13 The diagram illustrates the symmetrical reverse working mode of the resonant main beam. The quantity used to characterize this stiffness change is the magnitude of the stress on the main beam. Under the influence of differential pressure, the resonant main beam deforms, and its stiffness changes accordingly. This stiffness change causes a change in the natural frequency of the main beam, which can be indirectly measured by measuring the resonant frequency. Because the stiffness change of the main beam is proportional to the magnitude of the stress, the differential pressure can be assessed by monitoring the stress on the main beam.

[0053] Relationship between stress change and differential pressure: Figure 14 The stress variation transmitted to the resonant main beam of the structural layer is shown (original image from COMSOL simulation data), illustrating how the stress on the resonant main beam changes with pressure. Figure 14 It can be seen that for every 100 kPa increase in differential pressure, the stress on the main beam increases by 0.2 MPa. This indicates that the sensor can detect relatively small pressure changes, and that such stress changes are sufficient to cause a significant change in the resonant frequency, thus allowing differential pressure measurement by detecting the frequency change.

[0054] Measuring range and accuracy: according to Figure 14 The data shows that the sensor has a full-range pressure of 50 MPa and can detect differential pressure changes of 100 kPa. This demonstrates that the sensor of this invention can not only withstand high-pressure environments but also possesses high accuracy and resolution. Therefore, this sensor is suitable for applications requiring high-precision pressure measurement.

[0055] Experiments show that the lever differential pressure sensor of this invention amplifies the lateral displacement caused by the differential pressure and utilizes the stress change of the resonant main beam to achieve accurate measurement of the differential pressure. Its structural design and COMSOL simulation results demonstrate that the sensor can achieve a differential pressure measurement of 100 kPa under a static pressure of 50 MPa, exhibiting high sensitivity, high accuracy, and good linearity, making it suitable for pressure measurement under high-pressure environments.

[0056] The above embodiments are merely preferred embodiments of the present invention and should not be considered as limiting the scope of the present invention. All equivalent variations and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure, characterized in that... From bottom to top, the structure consists of a lower pressure-sensitive layer, a lower glass layer, a lever layer, a lower substrate layer, an upper substrate layer, a structural layer, an upper glass layer, and an upper pressure-sensitive layer. The upper pressure-sensitive layer, lower pressure-sensitive layer, upper substrate layer, lower substrate layer, and structural layer are all made of silicon material, and the substrate layer is made of BF33 borosilicate glass. The upper and lower pressure-sensitive layers are used to bear load pressure. When bearing load pressure, the pressure diaphragm deforms, thereby causing the mass blocks of other layers to deflect. The mass blocks of each layer amplify the lateral displacement and transmit it to the structural layer through the lever layer and the lever structure connecting the upper and lower substrate layers. This causes the resonant beam on the structural layer to generate axial internal stress, causing the resonant frequency of the resonator to change, thereby characterizing the pressure. The upper and lower glass layers serve as encapsulation layers to form a high-vacuum sealed cavity. The upper pressure-sensitive layer includes an upper pressure-sensitive membrane and four electrode holes, and the lower pressure-sensitive layer includes a lower pressure-sensitive membrane. The upper pressure-sensitive membrane is located on one side of the upper pressure-sensitive layer, and the lower pressure-sensitive membrane is located on one side of the lower pressure-sensitive layer, forming a reverse symmetrical distribution. The upper and lower pressure-sensitive membranes transmit the detected pressure deformation to the cover plates of each layer of the sensor structure. The upper and lower pressure-sensitive membranes are symmetrically distributed, and the four electrode holes are located around the upper pressure-sensitive layer.

2. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... The structural layer includes a resonant main beam, a resonant secondary beam, a mass block, a lever cover plate, a fixed drive end tooth, a drive electrode, a moving resonant end tooth, a detection piezoresistive beam, a detection electrode, and a grounding electrode. The resonant main beam and the resonant secondary beam are interconnected. The moving tooth at the resonant end is integral with the resonant secondary beam and connected to the resonant main beam. The fixed tooth at the driving end is connected to the driving electrode. The resonant secondary beam is connected to the piezoresistive detection beam and the grounding electrode at its end; one end of the resonant main beam is connected to the lever cover plate and the other end is connected to the resonator mass block; the mass block is located at the center of the resonator, and only one end of the mass block is connected to the lever cover plate, while the other end is not fixed. The lever cover plates are symmetrically distributed and connected to the resonator; the detection piezoresistive beams are symmetrically distributed and connected, and are all connected to the detection electrodes.

3. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... Both the upper and lower glass layers are made of BF33 borosilicate glass. The upper glass layer has a device groove corresponding to the lever layer in the center, and the lower glass layer has electrode holes corresponding to the four electrodes of the resonant layer and release grooves for the movable structure of the resonant layer.

4. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... The lever layer includes a lever cover plate, a lever support beam, and a lever transmission anchor point.

5. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... The upper substrate layer includes a substrate support lever cover plate, a substrate layer lever transfer block, and a substrate layer movable structure release groove; the lower substrate layer includes a lever support beam substrate groove and a substrate layer lever support beam anchor point.

6. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... The pressure-sensitive membrane is rectangular or rectangular in shape.

7. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... The upper pressure-sensitive layer and the lower pressure-sensitive layer are symmetrically distributed on both sides of the upper glass layer and the lower glass layer.

8. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 2, characterized in that... The resonant main beam, resonant secondary beam, and detection piezoresistive beam are all symmetrically distributed on both sides of the resonator.

9. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 2, characterized in that... The two ends of the resonant main beam are connected to the lever cover plate and the mass block, respectively. The mass block is connected to the lever cover plate on only one side, and the other side is not fixed.

10. The high differential pressure sensitivity dual-film resonant pressure sensor based on a lever structure as described in claim 1, characterized in that... The four electrode holes are evenly distributed on the upper pressure-sensitive layer and the upper glass layer, and correspond to the positions of the detection and driving electrodes of the resonant layer.

Images