A deformation detection integrated micro-nano sensor and a manufacturing method and a detection method thereof

Abstract

Provided is a deformation detection micro-nano integrated sensor, a substrate is an SOI silicon wafer, a deformation detection unit and a temperature detection unit are arranged on the front surface of the substrate of a first chip, a vibration detection unit is independently arranged on the substrate of a second chip, and signal isolation is realized through packaging; the deformation detection unit is a silicon-based piezoresistive strip structure, the temperature detection unit is a platinum thin film temperature-sensitive resistor, and the vibration detection unit is a capacitive structure formed by arranging corresponding metal electrodes on the front surface and back surface of the substrate of the vibration detection unit; when vibrating, the micro displacement of the mass block relative to the metal electrode causes a change in the distance between the electrode plates to detect vibration information; the temperature detection unit and the vibration detection unit provide corresponding compensation for the deformation detection parameters; thus, more accurate deformation parameters are obtained through detection; each detection unit is provided with a wiring pad and a conductive lead; a manufacturing method and a detection method are also provided; and the sensitivity and accuracy of deformation detection under temperature changes and vibration environments are significantly improved.

Description

Technical Field

[0001] This invention belongs to the field of deformation detection and micro / nano sensor technology, and relates to an integrated micro / nano sensor for deformation detection, its fabrication method and detection method, and in particular a high-precision strain sensor integrating temperature and vibration compensation, its fabrication method and detection method. Background Technology

[0002] In the fields of structural health monitoring and precision instrument measurement, the accuracy and reliability of strain sensors directly affect the safe operation and performance evaluation of critical equipment. Currently, although various strain detection technologies have been applied in engineering practice, they still face severe challenges under complex operating conditions: ambient temperature fluctuations can cause significant drift in sensor signals, while mechanical vibration interference can mask the true strain information, leading to distorted measurement data. Especially in high-end applications such as aerospace and new energy equipment, existing sensors struggle to effectively overcome the combined interference of temperature and vibration while detecting minute strains, severely limiting their ability to accurately monitor critical components. Therefore, there is an urgent need to develop a novel strain sensing solution with multi-physics compensation capabilities to overcome the technical bottleneck of high-precision measurement in complex environments.

[0003] Currently, in the field of new energy battery safety monitoring, metal foil strain gauges are widely used due to their simple structure and stable performance. However, their sensitivity coefficient (GF) is typically only around 2, which is insufficient to meet the needs of micro-strain detection. To improve sensitivity, researchers have turned to semiconductor piezoresistive strain gauges, which utilize the resistivity change caused by lattice deformation to increase the GF to over 50, or even exceeding 170, significantly outperforming traditional metal strain gauges. However, semiconductor strain gauges still face severe challenges in practical applications: especially under complex dynamic conditions such as new energy vehicle battery packs, temperature fluctuations and mechanical vibrations introduce significant cross-interference, leading to output signal distortion and severely limiting their reliability and measurement accuracy in real-world scenarios.

[0004] To address temperature interference, existing research has proposed integrating temperature compensation units into sensors. For example, this involves integrating a platinum temperature sensor with a silicon piezoresistive sensitive gate on the same chip, utilizing a Wheatstone full-bridge structure and real-time temperature monitoring to achieve effective temperature compensation. However, in vibration environments, the additional strain generated by inertial forces on the sensor substrate and sensitive structure still interferes with the extraction of the true deformation signal. Current MEMS vibration sensor research largely focuses on earthquake monitoring or high-temperature vibration measurement. For instance, the asymmetric anti-spring capacitive accelerometer proposed by Xi'an Jiaotong University has a frequency dynamic range of 0–158 Hz and a sensitivity of 21.3 mV / g; the SiC piezoresistive MEMS accelerometer developed by Beijing University of Aeronautics and Astronautics is suitable for high-temperature environments above 500℃, with a dynamic sensitivity of 0.21 mV / g. However, none of these sensors are optimized for micro-strain measurement and vibration interference compensation of battery packs under complex mechanical vibration environments, lacking strain-vibration coordinated sensing and real-time compensation capabilities.

[0005] Therefore, this project aims to overcome the limitations of existing single-parameter sensors and propose a high-precision micro-strain sensor that integrates the coordinated sensing of three parameters: deformation, temperature, and vibration. As exemplified by the applicant's patent application entitled "An Integrated Micro / Nano Sensor for Deformation Detection and Its Fabrication and Detection Method," application number 202411306205.2, application date 2024.09.19, publication date 2025.01.28, this sensor can reduce the influence of temperature and vibration effects.

[0006] However, attempts to integrate a piezoresistive strain gauge and a piezoresistive vibration detection unit onto a single chip revealed two key technical bottlenecks:

[0007] Severe electrical and mechanical coupling: There is significant parasitic capacitance coupling between the driving signal of the vibration unit and the weak output signal of the deformation unit; at the same time, mechanical vibration stress is directly transmitted to the deformation-sensitive gate through the common silicon substrate, resulting in a deterioration of the measurement signal-to-noise ratio and a fundamental limitation on the compensation accuracy.

[0008] Nested temperature error sources: The resistance value of the piezoresistive vibration detection unit itself is also sensitive to temperature. This means that while it is trying to compensate for the temperature drift of the deformation signal, its own output becomes a new and difficult-to-separate temperature error source, forming nested interference in the compensation logic, making system-level temperature compensation extremely complex and with limited effectiveness.

[0009] These bottlenecks make it difficult for such highly integrated single-chip sensors to meet high-precision requirements in terms of measurement stability and reliability under complex dynamic conditions.

[0010] To overcome the aforementioned limitations, this invention abandons the "all-piezoresistive, single-chip" integration approach and instead proposes the core concepts of "piezoresistive-capacitive hybrid sensing" and "partitioned isolation integration." This invention aims to provide a high-precision strain sensing system that fundamentally eliminates electrical and mechanical coupling and employs an independent sensing principle with lower temperature drift for vibration detection. Specifically, the innovation of this invention lies in:

[0011] The sensing principles are mixed: deformation and temperature detection use the highly sensitive piezoresistive and platinum resistance principles, while vibration detection uses the capacitive principle, which is relatively insensitive to temperature and the driving and detection signals are easy to isolate.

[0012] Structural partitioning and isolation: The piezoresistive deformation and temperature units, which are susceptible to interference, are physically fabricated separately from the capacitive vibration units, and then integrated into the system through subsequent packaging. This design completely cuts off the mechanical stress transmission path between units through the substrate and greatly reduces parasitic coupling between circuits.

[0013] Therefore, this invention is not a simple patchwork of existing sensors, but rather a creatively proposed system architecture of "hybrid sensing principle + partitioned isolation integration" to address the specific technical challenge of "multi-dimensional dynamic compensation of piezoresistive high-precision deformation sensors under complex working conditions." This architecture systematically solves the problems of signal crosstalk and error nesting by selecting specific sensing principles and combining and physically isolating them, ultimately achieving an overall measurement performance improvement of "1+1>2," providing a reliable solution for high-precision micro-strain measurement under combined vibration and temperature interference environments.

[0014] This invention integrates a piezoresistive strain gauge unit and a platinum temperature sensor on a MEMS chip, and encapsulates and integrates a capacitive vibration detection unit. It utilizes a folded beam-mass block structure to achieve vibration sensing and extracts vibration interference information through a capacitive detection mechanism. Combined with a multi-physics coupling compensation model, it achieves real-time decoupling and correction of micro-strain signals, thereby significantly improving the measurement accuracy and reliability of the sensor under complex dynamic conditions, and providing a new generation of sensing solutions for early safety warning of new energy batteries. Summary of the Invention

[0015] The technical problem to be solved by the present invention is to provide a high-precision integrated micro-nano sensor for deformation detection with integrated temperature and vibration compensation, which is fabricated using micro-nano fabrication technology, and its fabrication and detection methods.

[0016] To solve the above-mentioned technical problems, the technical solution of the high-precision strain sensor with temperature and vibration compensation of the present invention is as follows:

[0017] An integrated micro / nano sensor for deformation detection includes a deformation detection unit (1), a temperature detection unit (2), and a vibration detection unit (3). The sensor comprises a first chip and a second chip isolated from each other. Both the first chip and the second chip include a substrate, which is an SOI silicon wafer. The deformation detection unit (1) and the temperature detection unit (2) are jointly disposed on the front side of the substrate of the first chip, while the vibration detection unit (3) is independently disposed on the substrate of the second chip. Signal isolation is achieved through encapsulation to avoid crosstalk between electrical signal coupling and mechanical stress. The deformation detection unit (1) is a silicon-based piezoresistive strip structure, formed by boron ion doping into a zigzag silicon-based piezoresistive strip (4). The temperature detection unit (2) is a platinum thin-film thermistor, disposed in the vicinity of the deformation detection unit (1) and electrically isolated from it. The vibration detection unit (3) is formed by setting corresponding metal electrodes on the front and back sides of its substrate. The substrate is formed by wet etching to form a mass block (11) that can sense vibration. When vibrating, the micro-displacement of the mass block (11) relative to the metal electrode causes the change in the electrode spacing to detect vibration information. The temperature detection unit (2) and the vibration detection unit (3) are used to eliminate the interference of temperature change and vibration of the working environment on high-precision measurement and to provide corresponding compensation for deformation detection parameters. The final detection value of deformation is based on the deformation parameters detected by the deformation detection unit (1). At the same time, the temperature parameters detected by the temperature detection unit (2) and the vibration parameters detected by the vibration detection unit (3) are used to compensate for the deformation parameters detected by the deformation detection unit (1), so as to obtain more accurate deformation parameters. The deformation detection unit (1) and temperature detection unit (2) on the front of the first chip are provided with wiring pads and conductive leads. The vibration detection unit (3) on the second chip is provided with wiring pads and conductive leads.

[0018] The following is a further embodiment of the deformation detection integrated micro / nano sensor of the present invention:

[0019] The deformation detection unit (1) is a strip-shaped silicon-based piezoresistive strip (4) formed by doping boron ions on a silicon wafer and in a tortuous and reciprocating state. Four identical strip-shaped silicon-based piezoresistive strips (4) are connected in sequence to form a four-resistance bridge. The four strip-shaped silicon-based piezoresistive strips (4) are respectively led out with conductive leads to connect to the first wiring pad (5) for connecting the external power supply and the external detection circuit.

[0020] The strip-shaped silicon-based piezoresistive strip (4) includes a heavily doped region (8) and a lightly doped region (9). The fold-back section of the strip-shaped silicon-based piezoresistive strip (4) is the heavily doped region (8), and the long straight strip connected between the fold-back sections is the lightly doped region (9), so that the resistance distribution of the strip-shaped silicon-based piezoresistive strip (4) is uniform. Before doping the silicon wafer with boron ions, the doped region reserved as the strip-shaped silicon-based piezoresistive strip (4) and the undoped region not used as the functional region of the strip-shaped silicon-based piezoresistive strip (4) are first delineated. The undoped region is the etching target.

[0021] The temperature detection unit (2) includes a temperature platinum resistance thermometer (6) arranged in a zigzag pattern, conductive leads, and a second wiring pad (7), which is fabricated on the top silicon layer of the deformation monitoring unit. The deformation and temperature detection unit (2) are isolated by the insulating material silicon nitride. The second wiring pad (7) is used to connect the external power supply and the detection circuit. The temperature platinum resistance thermometer (6) is formed by depositing a layer of metal platinum on the insulating layer using a lift-off process. Alternatively, the temperature detection unit (2) is formed by depositing a relatively thin layer of metal chromium and a relatively thick layer of metal platinum on the insulating layer using a lift-off process. The wiring pad and conductive leads are both made of metal gold using a magnetron sputtering process.

[0022] The vibration detection unit (3) is configured as follows: the substrate of the second chip is etched with a wet etching process to create an etching groove (15), and a cavity (16) is formed by further wet etching through the etching groove (15). The layer above the cavity surrounded by the etching groove (15) serves as the mass block (11). A connecting bridge spanning the etching groove (15) is maintained between the substrate of the second chip and the mass block (11) to support the mass block (11), so that the mass block (11), the etching groove (15), and the connecting bridge are suspended below. When there is an external vibration input, the vibration of the mass block (11) and the connecting bridge will cause the distance between the metal electrodes set on the upper and lower parts of the substrate to change, thereby causing a change in capacitance. During vibration, the micro-displacement of the mass block (11) relative to the metal electrodes will cause a change in the electrode spacing to detect vibration information. Conductive leads are led out from the upper and lower parts of the substrate to connect to the third wiring pad (10), which are used to connect the external power supply and the external detection circuit respectively. The vibration detection unit (3) defines the thickness of the mass block (11) through photolithography and etching, and defines the height of the cavity (16) through sidewall protection. Through metal deposition and patterning, it forms two electrodes, metal leads and a third connection pad (10). The front electrode (13) and the back electrode (14) are arranged vertically and vertically, while the positions of the pad and the metal wire are staggered vertically, thereby effectively avoiding capacitive coupling and parasitic interference between signal channels and improving the independence and anti-interference capability of the detection signal. The front and back sides of the substrate of the second chip are sputtered with Cr / Au metal films, and the metal is patterned by ion beam etching (IBE) process to form upper and lower metal electrodes, conductive leads and a third connection pad (10).

[0023] The corrosion groove (15) includes a longitudinal corrosion groove (15) and a transverse corrosion groove (15), forming a rectangular mass block (11). The corrosion groove (15) and the connecting bridge are arranged as follows: a through longitudinal corrosion groove (15) is located on the left and right sides of the mass block (11), and the reserved portions on the upper and lower sides of the mass block (11) form a cross beam. A cross-shaped corrosion groove (15) is opened in the cross beam. A symmetrical strip-shaped folded connecting bridge (12) in a tortuous and reciprocating state is formed on the upper and lower sides of the mass block (11); or, a connecting bridge is reserved in the middle of the longitudinal corrosion groove (15) and the transverse corrosion groove (15).

[0024] Two straight-line etched grooves (15) are opened in the middle of the mass block (11), and two straight-line etched grooves (15) are also opened in the middle of the metal electrode; the metal leads on the front are led out along the strip-shaped folded connecting bridge (12); after the deformation detection integrated micro-nano sensor is fabricated, the first chip and the second chip are integrated and packaged using a metal package shell (17).

[0025] To prevent electrical and mechanical coupling effects between different sensing units, this invention does not fabricate the temperature detection unit, deformation detection unit, and vibration detection unit on the same silicon wafer. Instead, it adopts a partitioned integration or chip-based design. This design effectively avoids signal interference caused by parasitic capacitance, resistance, and mechanical stress transmission, ensuring the independence of the output signals of each detection unit and the accuracy of the detection results, thereby improving the overall system reliability and measurement stability.

[0026] The vibration detection unit of this invention adopts the capacitive detection principle, which, compared with piezoresistive, piezoelectric, and electromagnetic induction vibration sensors, has advantages such as high sensitivity, low noise, good temperature stability, low power consumption, and easy integration with CMOS circuits. Its output signal depends on the change in electrode spacing, and can generate a significant capacitance change under extremely small mechanical displacement, thereby achieving high-precision detection of micro-vibrations. It is especially suitable for vibration monitoring and deformation signal compensation under complex working conditions.

[0027] To solve the above-mentioned technical problems, the technical solution adopted in the fabrication method of the deformation detection integrated micro / nano sensor of the present invention is as follows:

[0028] The fabrication method of the deformation detection integrated micro / nano sensor described above is characterized by the following steps on the first chip: fabrication of the deformation detection unit (1), formation of an insulating layer, fabrication of a temperature detection unit (2), and fabrication of each bonding pad; marking a strip-shaped silicon-based piezoresistive strip (4) retention area on the top silicon layer; performing ion implantation in the retention area to form a lightly doped region (9) and a heavily doped region (8); the deformation and temperature detection unit (2) includes the following steps:

[0029] Step 1: Use boron ion implantation process to fabricate strip silicon-based piezoresistive strips (4) on a thermally oxidized 600A silicon wafer. The implantation tilt angle is selected between 7° and 9°, and the sheet resistance value is between 72 and 90Ω.

[0030] Step 2: LPCVD deposition of 1500A-3000A low-stress silicon nitride as an insulating layer between the subsequently prepared metal and the top silicon layer, and as a surface mask for protection during subsequent wet etching;

[0031] Step 3: The Cr / Pt / Au metal film is prepared by magnetron sputtering and patterned by ion beam etching (IBE) to form the temperature detection unit (2) and the second wiring pad (7).

[0032] Step 4: Deposit silicon nitride (Si3N4) of 1500A-3000A using plasma chemical vapor deposition (PECVD) as the insulating layer for the temperature detection unit (2) and interconnect leads;

[0033] Step 5: Use reactive ion etching (RIE) process with an etching depth of 1500A-3000A to remove the silicon nitride (Si3N4) insulating layer on the surface of each wiring pad and expose each wiring pad.

[0034] Step 6: Finally, chemical mechanical polishing (CMP) is used to thin the silicon wafer to 200μm-300μm.

[0035] The fabrication of a vibration detection unit (3) on a first chip includes the following steps:

[0036] Step 1: Clean the silicon wafer and prepare a 2000A silicon dioxide film on the upper surface of the silicon wafer using plasma-enhanced chemical vapor deposition. The silicon dioxide layer is used as an insulating layer, and its function is to achieve electrical isolation between the upper metal structure and the lower silicon substrate.

[0037] Step 2: Use reactive ion etching (RIE) to etch the silicon oxide film and pattern the etching grooves (15).

[0038] Step 3: Use deep reactive ion etching (DRIE) to etch a 30-micron deep silicon mass block (11) thickness. Ensure low stiffness within the limits achievable by the process.

[0039] Step 4: Combine organic adhesive removal process with adhesive removal process, and then oxidize again to form silicon oxide.

[0040] Step 5: Use reactive ion etching (RIE) to etch the silicon oxide at the bottom of the corrosion trench (15) to form a sidewall protection.

[0041] Step 6: Use Deep Reactive Ion Etching (DRIE) to etch silicon to a depth of 15 μm to define the cavity (16) height. This ensures high sensitivity.

[0042] Step 7: Use magnetron sputtering to prepare Cr / Au metal films on the front and back sides respectively, and use ion beam etching (IBE) to pattern the metal to form upper and lower electrodes, metal lines and third wiring pads (10).

[0043] Step 8: Deposit silicon nitride (Si3N4) to a depth of 1500A-3000A on the back side using plasma chemical vapor deposition (PECVD). Then, use reactive ion etching (RIE) to remove the silicon nitride (Si3N4) insulating layer on the pad surface to expose each wiring pad.

[0044] Step 9: Form a 15-micron cavity (16) through an anisotropic corrosion window to precisely form a folded beam-mass block (11) structure.

[0045] The following is a further embodiment of the fabrication method of the deformation detection integrated micro / nano sensor of the present invention:

[0046] In step 1, the thickness of the thermal oxidation is preferably 600 Å, the preferred ion implantation energy is 40 keV and the incident angle is 7°, to obtain a sheet resistance of about 2 Ω for heavy doping and about 80 Ω for light doping.

[0047] In step 2, LPCVD (low-pressure chemical vapor deposition) is preferred for depositing 3000A low-stress silicon nitride;

[0048] In step 3, the preferred thickness of the Cr / Pt / Au metal film is 500A / 3000A / 500A, the preferred metal line width of the temperature sensitive unit is 15μm, and the size of the second wiring pad (7) is 1mm*1mm;

[0049] In step 4, plasma chemical vapor deposition (PECVD) is preferred to deposit silicon nitride with a depth of 3000 Å.

[0050] In step 5, the preferred etching depth of silicon nitride is 3000 Å, which is consistent with the deposition thickness in step S4;

[0051] In step 6, the preferred thickness of the silicon wafer thinning is 250 μm.

[0052] A further method for manufacturing the vibration detection unit (3):

[0053] In step 1, the thickness of the thermal oxidation is preferably 2000 Å.

[0054] In step 2, silicon dioxide 2000A is preferably etched.

[0055] In step 4, the thickness of the second thermal oxidation is preferably 600 Å.

[0056] In step 5, silicon dioxide 600A is preferably etched.

[0057] In step 7, the preferred thickness of the Cr / Au metal film is 500A / 3000A, the preferred metal line width of the temperature sensitive unit is 30, 20, or 10 μm, and the size of the third wiring pad (10) is 1 mm * 1 mm.

[0058] In step 8, the preferred etching depth for silicon nitride is 3000 Å;

[0059] Finally, after the sensor is fabricated, the three sensor units are packaged and integrated using a metal casing. Each unit is physically and electrically independent, effectively avoiding signal coupling and mechanical stress crosstalk between multiple sensitive elements, thus improving system stability and reliability.

[0060] To solve the above-mentioned technical problems, the technical solution adopted by the detection method of the present invention is as follows:

[0061] The deformation detection method of this invention uses the deformation detection integrated micro-nano sensor described above. During detection, the first chip and the second chip are firmly fixed to the object being tested. A pair of pads in the deformation detection unit (1) are connected to an external power supply to provide excitation voltage to one pair of opposite ends of a four-resistance bridge. The other pair of pads in the deformation detection unit (1) are connected to an external voltage detection circuit. The temperature detection unit (2) is connected to an external temperature detection circuit via a pair of pads on it. A pair of parallel plate capacitors in the vibration detection unit (3) are connected to an external voltage detection circuit. When the object being tested is deformed due to an external impact, the other pair of opposite ends of the four-resistance bridge in the deformation detection unit (1) will output a voltage signal proportional to the deformation. The temperature detection unit (2) will output an instantaneous temperature signal via a pair of pads on it. The two ends of the parallel plate capacitor in the vibration detection unit (3) will output a voltage signal reflecting the current vibration of the object being tested. The relevant electrical signals of the three measured physical parameters are mathematically converted to eliminate the interference of temperature and vibration on deformation detection and to calculate the accurate deformation value.

[0062] The temperature detection unit and vibration detection unit are used to monitor changes in ambient temperature and external vibration input, respectively, and to compensate the output signal of the deformation detection unit in real time, thereby effectively eliminating the influence of ambient temperature drift and mechanical vibration on the accuracy of strain measurement and achieving high sensitivity and high stability deformation detection.

[0063] This invention relates to a high-precision strain sensor integrating temperature and vibration compensation, fabricated on a silicon wafer substrate. From bottom to top, it comprises a silicon resistive deformation sensing layer, an insulating layer, and a temperature sensing layer. The sensor is fabricated using MEMS microfabrication technology. The deformation detection unit and temperature detection unit are arranged in sections on the same chip, while the vibration detection unit is fabricated independently and then integrated through packaging. This structural layout effectively prevents electrical and mechanical coupling between units, ensuring independent signal output from each detection channel.

[0064] The sensor comprises three functional units: a deformation detection unit, a temperature detection unit, and a vibration detection unit. The deformation detection unit detects minute strains in the measured object; the temperature detection unit monitors changes in ambient temperature and provides temperature compensation; and the vibration detection unit senses external mechanical vibrations and performs vibration compensation. Through the synchronous acquisition, fusion, and decoupling of these three signals, high-precision strain measurement under complex working conditions can be achieved.

[0065] The deformation detection unit employs a piezoresistive effect-based structural design. Four serpentine piezoresistive strips with identical geometric dimensions and oriented along the ⟨110> crystal orientation of the single-crystal silicon are formed in the top silicon layer using a boron ion doping process. These four strips are connected in series to form a full-bridge structure. Under external deformation, the resistance of the silicon piezoresistive strips changes with stress, and a voltage signal proportional to the deformation is output through the bridge circuit. This full-bridge layout effectively improves detection sensitivity, eliminates common-mode interference from temperature drift, and exhibits excellent linear response characteristics.

[0066] The temperature detection unit employs a thin-film platinum resistance thermometer structure. A serpentine platinum thin-film resistor is deposited on a silicon nitride insulating layer using a lift-off process, with pads at both ends for connecting to an external temperature measurement circuit. The resistance of the platinum resistor changes linearly with temperature, allowing for real-time monitoring of ambient temperature. When the temperature changes, the temperature signal output by this unit is used to compensate for the output of the deformation detection unit, thereby eliminating the impact of temperature drift on measurement accuracy.

[0067] The vibration detection unit adopts a capacitive structure, consisting of a mass block, a folded beam support structure, and upper and lower electrode plates. The mass block is connected to the fixed frame through four sets of folded beams. The folded beams extend the equivalent beam length and reduce the structural stiffness, enabling a large displacement response under relatively small external accelerations. A parallel plate capacitor is formed between the mass block and the lower electrode. When external vibration occurs, the electrode spacing changes slightly, causing a change in the capacitance value. By detecting the capacitance signal in real time, vibration intensity and direction information can be obtained. Compared with piezoresistive and piezoelectric vibration detection methods, the capacitive structure has advantages such as high sensitivity, low noise, good temperature stability, and low power consumption, making it particularly suitable for micro-vibration detection and signal compensation in complex environments.

[0068] In use, the high-precision micro-strain sensor integrating temperature and vibration compensation is fixed to the surface of the object being measured by adhesive bonding or bolting. The output signals of the deformation detection unit, temperature detection unit, and vibration detection unit are connected to external circuitry via solder pads, enabling synchronous acquisition of three electrical signals. By performing temperature and vibration compensation processing on the deformation signal, measurement errors can be significantly reduced, resulting in highly stable and high-resolution deformation output. This structure allows for sensor miniaturization and mass production, and is suitable for battery pack structure monitoring and strain detection in vibration environments of mechanical equipment.

[0069] Compared with the prior art, the present invention has the following beneficial effects:

[0070] (1) Significantly improves the sensitivity and accuracy of deformation detection under temperature change and vibration environment.

[0071] (2) When there is an external vibration input, the mass block will also vibrate, thereby changing the distance between the two electrodes and causing a change in capacitance. By detecting the effect of vibration on capacitance, vibration compensation for strain measurement can be achieved, thus eliminating the vibration effect of semiconductor devices during operation to the greatest extent.

[0072] (3) Precise matching of physical principles and detection targets: Deformation detection adopts the highly sensitive semiconductor piezoresistive effect, temperature detection adopts the linear and stable metal thermal resistance effect (platinum resistance), and vibration detection introduces the variable gap capacitance effect that is almost insensitive to temperature. This approach achieves natural decoupling of the three signals of strain, temperature, and vibration from the source of sensing, eliminating cross-sensitivity and error nesting caused by overlapping principles.

[0073] (4) The bridge layout of the serpentine mechanical sensitive grid is adopted to improve the measurement sensitivity and reduce the influence of temperature on semiconductor devices. Combined with the highly integrated temperature detection platinum resistance, temperature compensation for strain measurement is realized, and the temperature effect of semiconductor devices during operation is eliminated to the greatest extent.

[0074] (5) The vibration detection unit adopts a folded beam-mass block structure design. Compared with the traditional single cantilever beam or straight beam structure, the folded beam structure can generate a larger displacement response under the same external excitation by extending the equivalent beam length and reducing the structural stiffness, thereby significantly improving the sensor sensitivity. At the same time, the folded beam has the characteristics of good symmetry and uniform stress distribution, which can effectively reduce the output drift caused by transverse stress coupling and thermal stress, and improve the detection linearity and temperature stability.

[0075] (6) Through the physical design of partitioned fabrication and packaging integration, the deformation-temperature unit based on the piezoresistive / thermal resistance principle and the capacitive vibration unit are rigidly isolated on the mechanical substrate and electrical traces, which completely blocks the parasitic coupling path between the vibration stress and the driving signal through the direct transmission of the substrate.

[0076] (7) The present invention realizes the miniaturization and mass production of devices based on MEMS technology, and has the advantages of simple structure, low cost and high stability. Attached Figure Description

[0077] Figure 1 This is a top-view schematic diagram of the deformation and temperature detection unit on the first chip.

[0078] Figure 2 This is a front view of the vibration detection unit on the second chip.

[0079] Figure 3 This is a schematic diagram of the vibration detection unit on the back of the second chip.

[0080] Figure 4 This is a cross-sectional view of the second chip vibration detection unit.

[0081] Figure 5 This is a schematic diagram of the hypothetical separation state of each layer in the vibration detection unit of the second chip.

[0082] Figure 6 A front-view perspective view of the integration of the three functional units of the first chip and the second chip.

[0083] Figure 7 A three-dimensional back view of the integration of the three functional units of the first chip and the second chip.

[0084] Figure 8 This is a schematic diagram of the integrated packaging of the three functional units of the first chip and the second chip.

[0085] Figure 9 A schematic diagram showing the connection of an external detection circuit to the deformation detection unit.

[0086] Figure 10 A schematic diagram showing the connection of an external detection circuit to the temperature detection unit.

[0087] Figure 11 A schematic diagram showing the connection of an external detection circuit to the vibration detection unit.

[0088] The parts indicated by the numbers in each figure are: 1. Deformation detection unit; 2. Temperature detection unit; 3. Vibration detection unit; 4. Strip-shaped silicon-based piezoresistive strip; 5. First wiring pad; 6. Temperature platinum resistance; 7. Second wiring pad; 8. Heavily doped region; 9. Lightly doped region; 10. Third wiring pad; 11. Mass block; 12. Folded beam; 13. Front electrode; 14. Back electrode; 15. Etched edge groove; 16. Cavity; 17. Encapsulation shell. Detailed Implementation

[0089] The following combination Figures 1 to 11 The embodiments shown provide a further detailed description of the present invention.

[0090] This invention discloses a high-precision strain sensor integrating temperature and vibration compensation, such as... Figure 1 Figure 2 Figure 3 Figure 6 Figure 7 As shown, silicon is used as the substrate, and a detection unit is set on the upper surface. The detection unit includes a deformation detection unit 1. In order to eliminate the interference of vibration and temperature changes in the working environment on high-precision measurement and to provide corresponding compensation for the deformation detection parameters, it also includes a temperature detection unit 2 and a vibration detection unit 3. The final detection value of deformation is based on the deformation parameters detected by the deformation detection unit 1, and the temperature parameters detected by the temperature detection unit 2 and the vibration parameters detected by the vibration detection unit 3 are used to compensate for the deformation parameters detected by the deformation detection unit 1.

[0091] like Figure 1 , Figure 6 As shown, the deformation detection unit 1 is a strip-shaped silicon-based piezoresistive bar 4 formed by etching boron ions doped into a silicon wafer, exhibiting a tortuous and reciprocating state. Four identical strip-shaped silicon-based piezoresistive bars 4 are connected sequentially to form a four-resistance bridge. Conductive leads are led out from the four sets of strip-shaped silicon-based piezoresistive bars 4 to connect to the first wiring pad 5, which is used to connect to the external power supply and the external detection circuit, forming a Wheatstone bridge.

[0092] like Figure 1 , Figure 6 As shown, the temperature detection unit 2 includes a temperature platinum resistance thermometer 6 arranged in a serpentine pattern, conductive leads, and a second wiring pad 7, which is fabricated on top of the deformation detection unit and isolated from the deformation detection unit below by an insulating material, silicon nitride; the second wiring pad 7 is used to connect an external power supply and a detection circuit; the temperature platinum resistance thermometer 6 is formed by depositing a layer of metallic platinum on an insulating solid using a lift-off process.

[0093] like Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, the vibration detection unit 3 is implemented using a capacitive micromechanical sensor based on the variable electrode distance principle. It mainly consists of a movable mass block 11, a folded beam 12 support system, a front electrode 13, a back electrode 14, and corresponding detection circuitry. The movable mass block 11 serves as the inertial sensing unit of the sensor and the movable plate of the capacitor. The folded beam 12 support system connects the movable mass block to the fixed anchor point, providing elastic support for the mass block and primarily constraining its degrees of freedom of motion in the direction perpendicular to the electrode plane. The electrodes, including the front electrode 13 and the back electrode 14, are arranged parallel to each other, forming a parallel plate capacitor structure. The front electrode 13 is fabricated above the mass block 11, and the back electrode 14 is fixed to the back of the vibration detection unit 3. A cavity 16 is formed below the mass block 11 using a wet etching process, suspending the folded beam 12 and the mass block 11 below. Electrodes 13 and 14 are arranged vertically, with the fixed back electrode 14 on the lower layer and the movable electrode 13 fixed to the mass block 11 on the upper layer. The third wiring pad 10 and the metal wire are staggered vertically to avoid parasitic capacitance coupling and signal crosstalk, thus improving the independence and anti-interference capability of the detection signal. The folded beam structure significantly reduces structural stiffness while maintaining a compact overall size, improving low-frequency response sensitivity and linearity. This structure also has good fabrication compatibility and can be mass-produced using MEMS processes.

[0094] like Figure 1 , Figure 6As shown, the temperature detection unit 2 is a temperature platinum resistance 6 formed by depositing a relatively thin layer of metallic chromium and a relatively thick layer of metallic platinum on the insulating layer using a lift-off process; the first wiring pad 5, the second wiring pad 7, and the third wiring pad 10 are all gold pads made of metallic gold using a magnetron sputtering process.

[0095] like Figure 8 After the high-precision strain sensor integrating temperature and vibration compensation is manufactured, the three units are integrated and packaged in a metal encapsulation shell 17.

[0096] This invention discloses a method for fabricating a high-precision strain sensor integrating temperature and vibration compensation, comprising the fabrication of a deformation detection unit 1, a temperature detection unit 2, and various wiring pads, and performing ion implantation in the reserved area to form a lightly doped region 9 and a heavily doped region 8; including the following steps:

[0097] Step 1: Use boron ion implantation to fabricate a strip-shaped silicon-based piezoresistive strip on a thermally oxidized 600A silicon wafer. The implantation angle is selected between 7° and 9°, and the sheet resistance value is between 72 and 90Ω.

[0098] Step 2: LPCVD deposition of 1500A-3000A low-stress silicon nitride as an insulating layer between the subsequently prepared metal and the top silicon layer, and as a surface mask for protection during subsequent wet etching;

[0099] Step 3: The Cr / Pt / Au metal film is prepared by magnetron sputtering and patterned by ion beam etching (IBE) to form the temperature detection unit and the second wiring pad.

[0100] Step 4: Deposit silicon nitride (Si3N4) with an Å of 1500A-3000A using plasma chemical vapor deposition (PECVD) as the insulating layer for the temperature sensing unit and interconnect leads;

[0101] Step 5: Use reactive ion etching (RIE) process with an etching depth of 1500A-3000A to remove the silicon nitride (Si3N4) insulating layer on the surface of each wiring pad and expose each wiring pad.

[0102] Step 6: Finally, chemical mechanical polishing (CMP) is used to thin the silicon wafer to 200μm-300μm.

[0103] The vibration detection unit includes the following steps:

[0104] Step 1: Clean the silicon wafer and prepare a 2000A silicon dioxide film on the upper surface of the silicon wafer using plasma-enhanced chemical vapor deposition. The silicon dioxide layer is used as an insulating layer, and its function is to achieve electrical isolation between the upper metal structure and the lower silicon substrate.

[0105] Step 2: Use reactive ion etching (RIE) to etch the silicon oxide film and pattern the etching grooves.

[0106] Step 3: Employ Deep Reactive Ion Etching (DRIE) to etch silicon to a 30-micron depth to define the mass block thickness. Maintain low stiffness within the limits achievable by the process.

[0107] Step 4: Combine organic adhesive removal process with adhesive removal process, and then oxidize again to form silicon oxide.

[0108] Step 5: Use reactive ion etching (RIE) to etch the silicon oxide at the bottom of the corrosion trench to form sidewall protection.

[0109] Step 6: Use deep reactive ion etching (DRIE) to etch silicon to a depth of 15μm to define the cavity height.

[0110] Step 7: Prepare Cr / Au metal films on the front and back sides using magnetron sputtering, and pattern the metal using ion beam etching (IBE) to form upper and lower electrodes, metal lines and third wiring pads.

[0111] Step 8: Deposit silicon nitride (Si3N4) to a depth of 1500A-3000A on the back side using plasma chemical vapor deposition (PECVD). Then, use reactive ion etching (RIE) to remove the silicon nitride (Si3N4) insulating layer on the pad surface to expose each wiring pad.

[0112] Step 9: Through anisotropic corrosion windows, a 15-micron cavity is formed, precisely creating a folded beam-mass block structure.

[0113] The following is a further embodiment of the method for manufacturing the deformation and temperature detection unit of the present invention:

[0114] In step 1, the thickness of the thermal oxidation is preferably 600 Å, the preferred ion implantation energy is 40 keV and the incident angle is 7°, to obtain a sheet resistance of about 2 Ω for heavy doping and about 80 Ω for light doping.

[0115] In step 2, LPCVD (low-pressure chemical vapor deposition) is preferred for depositing 3000A low-stress silicon nitride;

[0116] In step 3, the preferred thickness of the Cr / Pt / Au metal film is 500A / 3000A / 500A, the preferred metal line width of the temperature-sensitive unit is 15μm, and the size of the third wiring pad is 1mm*1mm;

[0117] In step 4, plasma chemical vapor deposition (PECVD) is preferred to deposit silicon nitride with a depth of 3000 Å.

[0118] In step 5, the preferred etching depth of silicon nitride is 3000 Å, which is consistent with the deposition thickness in step S4;

[0119] In step 6, the preferred thickness of the silicon wafer thinning is 250 μm.

[0120] Furthermore, in the vibration detection step 1, the thickness of the thermal oxidation is preferably 2000 Å.

[0121] In step 2, silicon dioxide 2000A is preferably etched.

[0122] In step 4, the thickness of the second thermal oxidation is preferably 600 Å.

[0123] In step 5, silicon dioxide 600A is preferably etched.

[0124] In step 7, the preferred thickness of the Cr / Au metal film is 500A / 3000A, the preferred metal line width of the temperature sensitive unit is 30, 20, or 10 μm, and the size of the third wiring pad is 1 mm * 1 mm.

[0125] In step 8, the preferred etching depth for silicon nitride is 3000 Å.

[0126] Finally, after the sensors are fabricated, the three sensor units are encapsulated and integrated using the metal casing 17. Each unit is physically and electrically independent, effectively avoiding signal coupling and mechanical stress crosstalk between multiple sensitive elements, thus improving system stability and reliability.

[0127] In the detection process of this invention, the deformation detection integrated micro / nano sensor is connected to an external circuit, such as... Figure 9 As shown, the three units are securely fixed to the object being tested. During use, a pair of pads 5 in deformation detection unit 1 are connected to an external power supply, providing excitation voltage to one pair of opposite ends of a four-resistance bridge circuit. The other pair of pads 5 in deformation detection unit 1 are connected to an external voltage detection circuit. Figure 10 As shown, the temperature detection unit 2 is connected to an external temperature detection circuit via a pair of solder pads 7 on it. Figure 11 As shown, during use, a pair of parallel plate capacitors in vibration detection unit 3 are connected to an external voltage detection circuit. When the object being tested is deformed due to an external impact, the other pair of opposite ends of the four-resistance bridge in deformation detection unit 1 will output a voltage signal proportional to the deformation. Temperature detection unit 2 outputs an instantaneous temperature signal through a pair of solder pads 5 on it, and the two ends of the parallel plate capacitors in vibration detection unit 3 output a voltage signal reflecting the current vibration of the object being tested. The relevant electrical signals of the three measured physical parameters are mathematically converted to eliminate the interference of temperature and vibration on deformation detection and to calculate the accurate deformation value.

[0128] This invention addresses the inherent defects of fully piezoresistive single-chip integrated solutions under complex operating conditions—namely, severe electrical coupling between vibration and deformation signals, direct crosstalk of mechanical stress through a common substrate, and nested temperature errors introduced by the piezoresistive vibration detection unit itself—through fundamental architectural innovation. It innovatively proposes the core idea of ​​"multi-physics principle synergy and partitioned isolation integration": at the sensing principle level, three distinct physical mechanisms are systematically selected. The highly sensitive semiconductor piezoresistive effect is dedicated to deformation sensing, the stable and linear metal thermal resistance effect is used for temperature monitoring, and the variable gap capacitance effect, which is extremely insensitive to temperature changes, is independently responsible for picking up vibration signals. This achieves physical decoupling of the three key parameters—strain, temperature, and vibration—at the source, completely avoiding cross-sensitivity and nested errors caused by overlapping principles. At the system structure level, a creative physical design of partitioned fabrication and post-package integration is adopted. This allows the deformation-temperature composite unit based on the piezoresistive / thermal resistance principle and the vibration detection unit based on the capacitance principle to be rigidly isolated on the mechanical substrate and electrical interconnection path, effectively blocking the direct transmission path of vibration stress and the parasitic coupling channel between driving signals. This solution is not a simple patchwork of existing sensing elements, but a complete reconstruction from the sensing principle to the system architecture, specifically addressing the technical challenge of "high-precision micro-strain measurement in dynamic environments with strong vibration and wide temperature variations." It fundamentally solves the signal interference contradictions that previous technologies could not resolve, ultimately achieving a significant leap in the overall measurement signal-to-noise ratio, compensation accuracy, and long-term reliability of the system under extremely complex working conditions. This invention achieves multi-parameter integration, miniaturization, and high precision of the sensor, exhibiting excellent stability and reliability, and is suitable for complex environments such as battery pack structure monitoring and mechanical equipment vibration detection.

Claims

1. A deformation detection integrated micro / nano sensor, comprising a deformation detection unit (1), a temperature detection unit (2), and a vibration detection unit (3), characterized in that, The sensor includes a first chip and a second chip that are isolated from each other. Both the first chip and the second chip include a substrate, which is an SOI silicon wafer. The deformation detection unit (1) and the temperature detection unit (2) are jointly arranged on the front side of the substrate of the first chip, and the vibration detection unit (3) is independently arranged on the substrate of the second chip. Signal isolation is achieved through encapsulation to avoid crosstalk between electrical signal coupling and mechanical stress. The deformation detection unit (1) is a silicon-based piezoresistive strip structure, which is formed by boron ion doping into a strip-shaped silicon-based piezoresistive strip (4) in a tortuous and reciprocating state. The temperature detection unit (2) is a platinum thin film thermistor, which is arranged in the vicinity of the deformation detection unit (1) and electrically isolated from it. The vibration detection unit (3) is a capacitive structure formed by setting corresponding metal electrodes on the front and back sides of its substrate. Its substrate is formed by wet etching process to detect vibration. The mass block (11) and the micro-displacement of the mass block (11) relative to the metal electrode during vibration cause the change in the electrode spacing to detect vibration information; the temperature detection unit (2) and the vibration detection unit (3) are to eliminate the interference caused by temperature changes and vibration of the working environment to high-precision measurement and provide corresponding compensation for deformation detection parameters; the final detection value of deformation is based on the deformation parameters detected by the deformation detection unit (1), and the temperature parameters detected by the temperature detection unit (2) and the vibration parameters detected by the vibration detection unit (3) are used to compensate for the deformation parameters detected by the deformation detection unit (1), so as to obtain more accurate deformation parameters through detection; the deformation detection unit (1) and temperature detection unit (2) on the front of the first chip are provided with wiring pads and conductive leads, and the vibration detection unit (3) of the second chip is provided with wiring pads and conductive leads.

2. The deformation detection integrated micro / nano sensor as described in claim 1, characterized in that, The deformation detection unit (1) is a strip-shaped silicon-based piezoresistive strip (4) formed by doping boron ions on a silicon wafer and in a tortuous and reciprocating state. Four identical strip-shaped silicon-based piezoresistive strips (4) are connected in sequence to form a four-resistance bridge. The four strip-shaped silicon-based piezoresistive strips (4) are respectively led out with conductive leads to connect to the first wiring pad (5) for connecting the external power supply and the external detection circuit.

3. The deformation detection integrated micro / nano sensor as described in claim 2, characterized in that, The strip-shaped silicon-based piezoresistive strip (4) includes a heavily doped region (8) and a lightly doped region (9). The fold-back section of the strip-shaped silicon-based piezoresistive strip (4) is the heavily doped region (8), and the long straight strip connected between the fold-back sections is the lightly doped region (9), so that the resistance distribution of the strip-shaped silicon-based piezoresistive strip (4) is uniform. Before doping the silicon wafer with boron ions, the doped region reserved as the strip-shaped silicon-based piezoresistive strip (4) and the undoped region not used as the functional region of the strip-shaped silicon-based piezoresistive strip (4) are first delineated. The undoped region is the etching target.

4. The deformation detection integrated micro / nano sensor as described in claim 1, characterized in that, The temperature detection unit (2) includes a temperature platinum resistance thermometer (6) arranged in a zigzag pattern, conductive leads, and a second wiring pad (7), which is fabricated on the top silicon layer of the deformation monitoring unit. The deformation and temperature detection unit (2) are isolated by the insulating material silicon nitride. The second wiring pad (7) is used to connect the external power supply and the detection circuit. The temperature platinum resistance thermometer (6) is formed by depositing a layer of metal platinum on the insulating layer using a lift-off process. Alternatively, the temperature detection unit (2) is formed by depositing a relatively thin layer of metal chromium and a relatively thick layer of metal platinum on the insulating layer using a lift-off process. The wiring pad and conductive leads are both made of metal gold using a magnetron sputtering process.

5. The deformation detection integrated micro / nano sensor as described in claim 1, characterized in that, The vibration detection unit (3) is configured as follows: the substrate of the second chip is etched with a wet etching process to create an etching groove (15), and a cavity (16) is formed by further wet etching through the etching groove (15). The layer above the cavity surrounded by the etching groove (15) serves as the mass block (11). A connecting bridge spanning the etching groove (15) is maintained between the substrate of the second chip and the mass block (11) to support the mass block (11), so that the mass block (11), the etching groove (15), and the connecting bridge are suspended below. When there is an external vibration input, the vibration of the mass block (11) and the connecting bridge will cause the distance between the metal electrodes set on the upper and lower parts of the substrate to change, thereby causing a change in capacitance. When vibrating, the micro-displacement of the mass block (11) relative to the metal electrodes will cause a change in the electrode spacing to detect vibration information. Conductive leads are led out from the top and bottom of the substrate to connect to the third connection pad (10), which is used to connect to the external power supply and the external detection circuit. The vibration detection unit (3) defines the thickness of the mass block (11) by photolithography and etching, and defines the height of the cavity (16) by sidewall protection. Through metal deposition and patterning, two electrodes, metal leads and the third connection pad (10) are formed. The front electrode (13) and the back electrode (14) are arranged vertically and vertically, while the positions of the pad and the metal wire are staggered vertically, thereby effectively avoiding capacitive coupling and parasitic interference between signal channels and improving the independence and anti-interference ability of the detection signal. Cr / Au metal films are sputtered on the front and back of the substrate of the second chip, and the metal is patterned by ion beam etching (IBE) to form the upper and lower metal electrodes, conductive leads and the third connection pad (10).

6. The deformation detection micro / nano sensor as described in claim 5, characterized in that, The corrosion groove (15) includes a longitudinal corrosion groove (15) and a transverse corrosion groove (15), forming a rectangular mass block (11). The corrosion groove (15) and the connecting bridge are arranged as follows: a through longitudinal corrosion groove (15) is located on the left and right sides of the mass block (11), and the reserved portions on the upper and lower sides of the mass block (11) form a cross beam. A cross-shaped corrosion groove (15) is opened in the cross beam. A symmetrical strip-shaped folded connecting bridge (12) in a tortuous and reciprocating state is formed on the upper and lower sides of the mass block (11); or, a connecting bridge is reserved in the middle of the longitudinal corrosion groove (15) and the transverse corrosion groove (15).

7. The deformation detection micro / nano sensor as described in claim 6, characterized in that, Two straight-line etched grooves (15) are opened in the middle of the mass block (11), and two straight-line etched grooves (15) are also opened in the middle of the metal electrode; the metal leads on the front are led out along the strip-shaped folded connecting bridge (12); after the deformation detection integrated micro-nano sensor is fabricated, the first chip and the second chip are integrated and packaged using a metal package shell (17).

8. The method for fabricating a deformation detection micro / nano sensor as described in claim 1, characterized in that, The fabrication of the deformation detection unit (1), the formation of the insulating layer, the fabrication of the temperature detection unit (2), and the fabrication of each bonding pad are included on the first chip. A strip-shaped silicon-based piezoresistive strip (4) retention area is defined on the top silicon layer, and ion implantation is performed in the retention area to form a lightly doped region (9) and a heavily doped region (8). The deformation and temperature detection unit (2) includes the following steps: Step 1: Use boron ion implantation to fabricate a strip-shaped silicon-based piezoresistive strip (4) on a thermally oxidized 600A silicon wafer. The implantation tilt angle is selected between 7° and 9°, and its sheet resistance value is between 72 and 90Ω. Step 2: LPCVD deposition of 1500A-3000A low-stress silicon nitride as an insulating layer between the subsequently prepared metal and the top silicon layer, and as a surface mask for protection during subsequent wet etching; Step 3: The Cr / Pt / Au metal film is prepared by magnetron sputtering and patterned by ion beam etching (IBE) to form the temperature detection unit (2) and the second wiring pad (7). Step 4: Deposit silicon nitride (Si3N4) of 1500A-3000A using plasma chemical vapor deposition (PECVD) as the insulating layer for the temperature detection unit (2) and interconnect leads; Step 5: Use reactive ion etching (RIE) process with an etching depth of 1500A-3000A to remove the silicon nitride (Si3N4) insulating layer on the surface of each wiring pad and expose each wiring pad. Step 6: Finally, chemical mechanical polishing (CMP) is used to thin the silicon wafer to 200μm-300μm. The fabrication of a vibration detection unit (3) on a first chip includes the following steps: Step 1: Clean the silicon wafer and prepare a 2000A silicon dioxide film on the upper surface of the silicon wafer using plasma-enhanced chemical vapor deposition. The silicon dioxide layer is used as an insulating layer, and its function is to achieve electrical isolation between the upper metal structure and the lower silicon substrate. Step 2: Use reactive ion etching (RIE) to etch the silicon oxide film and pattern the etching grooves (15). Step 3: Use deep reactive ion etching (DRIE) to etch a 30-micron deep silicon mass block (11) thickness. Ensure low stiffness within the limits achievable by the process. Step 4: Combine organic adhesive removal process with adhesive removal process, and then oxidize again to form silicon oxide. Step 5: Use reactive ion etching (RIE) to etch the silicon oxide at the bottom of the corrosion trench (15) to form a sidewall protection. Step 6: Use Deep Reactive Ion Etching (DRIE) to etch silicon to a depth of 15 μm to define the cavity (16) height. This ensures high sensitivity. Step 7: Use magnetron sputtering to prepare Cr / Au metal films on the front and back sides respectively, and use ion beam etching (IBE) to pattern the metal to form upper and lower electrodes, metal lines and third wiring pads (10). Step 8: Deposit silicon nitride (Si3N4) to a depth of 1500A-3000A on the back side using plasma chemical vapor deposition (PECVD). Then, use reactive ion etching (RIE) to remove the silicon nitride (Si3N4) insulating layer on the pad surface to expose each wiring pad. Step 9: Form a 15-micron cavity (16) through anisotropic etching window, and precisely form a strip-shaped folded connecting bridge-mass block (11) structure.

9. The method for fabricating a deformation detection micro / nano sensor as described in claim 8, characterized in that, A further embodiment of the method for manufacturing the deformation and temperature detection unit (2) is as follows: In step 1, the thickness of the thermal oxidation is preferably 600 Å, the preferred ion implantation energy is 40 keV and the incident angle is 7°, to obtain a sheet resistance of about 2 Ω for heavy doping and about 80 Ω for light doping. In step 2, LPCVD (low-pressure chemical vapor deposition) is preferred for depositing 3000A low-stress silicon nitride; In step 3, the preferred thickness of the Cr / Pt / Au metal film is 500A / 3000A / 500A, the preferred metal line width of the temperature sensitive unit is 15μm, and the size of the second wiring pad (7) is 1mm*1mm; In step 4, plasma chemical vapor deposition (PECVD) is preferred to deposit silicon nitride with a depth of 3000 Å. In step 5, the preferred etching depth of silicon nitride is 3000 Å, which is consistent with the deposition thickness in step S4; In step 6, the preferred thickness of the silicon wafer thinning is 250 μm. A further method for manufacturing the vibration detection unit (3): In step 1, the thickness of the thermal oxidation is preferably 2000 Å. In step 2, silicon dioxide 2000A is preferably etched. In step 4, the thickness of the second thermal oxidation is preferably 600 Å. In step 5, silicon dioxide 600A is preferably etched. In step 7, the preferred thickness of the Cr / Au metal film is 500A / 3000A, the preferred metal line width of the temperature sensitive unit is 30, 20, or 10 μm, and the size of the third wiring pad (10) is 1 mm * 1 mm. In step 8, the preferred etching depth for silicon nitride is 3000 Å; Finally, after the sensor is fabricated, the three sensor units are packaged and integrated using a metal casing. Each unit is physically and electrically independent, effectively avoiding signal coupling and mechanical stress crosstalk between multiple sensitive elements, thus improving system stability and reliability.

10. A deformation detection method, characterized in that, Using the deformation detection integrated micro / nano sensor as described in any one of claims 1 to 7, during detection, the first chip and the second chip are firmly fixed to the object being detected. A pair of pads in the deformation detection unit (1) are connected to an external power supply to provide excitation voltage to one pair of opposite ends of a four-resistance bridge. The other pair of pads in the deformation detection unit (1) are connected to an external voltage detection circuit. The temperature detection unit (2) is connected to an external temperature detection circuit via a pair of pads on it. A pair of parallel plate capacitors in the vibration detection unit (3) are connected to an external voltage detection circuit. When the object being detected is deformed by an external force impact, the other pair of opposite ends of the four-resistance bridge in the deformation detection unit (1) will output a voltage signal proportional to the deformation. The temperature detection unit (2) will output an instantaneous temperature signal via a pair of pads on it. The two ends of the parallel plate capacitor in the vibration detection unit (3) will output a voltage signal reflecting the current vibration of the object being measured. The relevant electrical signals of the three measured physical parameters are mathematically converted to eliminate the interference of temperature and vibration on deformation detection and to calculate the accurate deformation value.

Images