High-temperature pressure-resistant MEMS pressure sensor and packaging technology thereof

Abstract

The application relates to the field of MEMS micro-machining technology, and discloses a high-temperature pressure-resistant MEMS pressure sensor and packaging technology thereof, the packaging method comprising the following steps: providing a to-be-mounted chip of the MEMS pressure sensor, sequentially depositing a passivation layer and a protective layer on the surface of the to-be-mounted chip, providing a high-temperature co-fired ceramic substrate, pre-mixing barium titanate and functional components to obtain a barium titanate-based glue, connecting the electrode layer with the metalized passage, providing a metal packaging shell, and filling preset filler between the ceramic substrate and the metal packaging shell; the low thermal expansion coefficient under a high-temperature environment avoids structural damage caused by material thermal expansion mismatch, the double-layer protection structure of the barium titanate-based glue and the preset filler improves the long-term stability and reliability of the sensor under a high-temperature and high-pressure environment, can effectively buffer thermal stress in a high-temperature environment, and prevents structural deformation or sealing failure of the sensor due to stress concentration under long-term high temperature and high pressure.

Description

Technical Field

[0001] The present invention relates to the field of MEMS micromachining technology, and in particular to a high-temperature and pressure-resistant MEMS pressure sensor and its packaging technology. Background Art

[0002] With the rapid development of modern industrial technology, the demand for pressure measurement in high-temperature, high-pressure, and harsh environments is increasing, particularly in sectors such as aerospace, automotive, oil and gas exploration, and nuclear energy. Conventional pressure sensors are unable to withstand these extreme operating conditions, leading to the emergence of MEMS (micro-electro-mechanical systems) pressure sensors with high-temperature and pressure resistance. MEMS technology, through miniaturization, integration, and high-precision sensor design, provides ultra-small, low-cost, and highly sensitive pressure measurement solutions. However, ensuring long-term stable sensor operation in these high-temperature and high-pressure environments, especially at temperatures exceeding 500°C, remains a major challenge for the industry.

[0003] Existing pressure sensors that are resistant to pressure and high temperatures mainly protect the sensor chip with epoxy resin or polymer materials, and then encapsulate it in a metal or ceramic shell. However, materials such as epoxy resin have limited temperature resistance. Under long-term high temperature, the filler protective layer is prone to deformation due to mismatched thermal expansion coefficients, affecting the reliability of the device and even causing sensor failure or damage.

[0004] Therefore, it is necessary to provide a high-temperature and pressure-resistant MEMS pressure sensor and its packaging technology to solve the problem that existing pressure-resistant and high-temperature-resistant pressure sensors are prone to deformation under long-term high temperature. Summary of the Invention

[0005] The main purpose of the present invention is to provide a high-temperature and pressure-resistant MEMS pressure sensor and its packaging technology, aiming to solve the technical problems mentioned in the above background technology.

[0006] The present invention adopts the following technical solutions:

[0007] A packaging technology for a high-temperature, pressure-resistant MEMS pressure sensor, comprising:

[0008] S100: providing a chip to be mounted with a MEMS pressure sensor, depositing a passivation layer and a protection layer on the surface of the chip to be mounted in sequence, and sputtering an electrode layer in the electrode region of the chip to be mounted;

[0009] S200: Providing a high-temperature co-fired ceramic substrate, wherein a mounting cavity is formed on the ceramic substrate, and sputtering a preset metal coating on the surface of the ceramic substrate to form a metallized path;

[0010] S300: premixing barium titanate and functional components to obtain barium titanate-based adhesive, mounting the chip to be mounted in the mounting cavity in a vacuum chamber, and spot-coating the barium titanate-based adhesive around the chip to be mounted to form a dam structure surrounding the chip to be mounted;

[0011] S400: connecting the electrode layer to the metallized path, injecting the barium titanate-based glue into the inner side of the dam structure, and dynamically curing the injected barium titanate-based glue and the dam structure;

[0012] S500: Providing a metal packaging shell, plating a preset metal layer on the surface of the metal packaging shell, and covering the ceramic substrate with the metal packaging shell;

[0013] S600: Filling a preset filler between the ceramic substrate and the metal packaging shell, and sintering at 600-700° C. to obtain a sealed high-temperature and pressure-resistant MEMS pressure sensor, and cooling the high-temperature and pressure-resistant MEMS pressure sensor to room temperature at a preset cooling rate.

[0014] Furthermore, the step of providing a chip to be mounted with a MEMS pressure sensor, depositing a passivation layer and a protective layer on the surface of the chip to be mounted, and sputtering an electrode layer in the electrode area of ​​the chip to be mounted, includes:

[0015] S101: Providing a MEMS pressure sensor chip based on a silicon-oxide-silicon structure, wherein the MEMS pressure sensor chip is formed with a plurality of electrode regions;

[0016] S102: forming a passivation layer on the surface of the MEMS pressure sensor chip by plasma enhanced chemical vapor deposition of silicon nitride, and depositing a protective layer on the passivation layer by physical vapor deposition of silicon oxide;

[0017] S103: performing pattern etching on the protection layer and the passivation layer based on the electrode region to expose the electrode region;

[0018] S104: sputtering the exposed electrode area using one of gold, platinum, or nickel to form an electrode layer, and making the thickness of the electrode layer equal to the sum of the thickness of the protective layer and the passivation layer;

[0019] S105: curing and connecting the electrode layer and the electrode region at 300-400° C., and annealing at 400-450° C. for 0.5-1 hour under nitrogen protection.

[0020] Furthermore, the step of providing a high-temperature co-fired ceramic substrate having a mounting cavity formed thereon and sputtering a preset metal coating on the surface of the ceramic substrate to form a metallized path includes:

[0021] S201: providing a high-temperature co-fired ceramic substrate, placing the ceramic substrate in a plasma cleaning device, and treating the ceramic substrate for 5 to 10 minutes using a mixed gas of argon and nitrogen as a cleaning medium, wherein the power density of the plasma cleaning device is set to 0.25 to 0.45 W / cm², and the flow ratio of argon to oxygen is 3 to 5:1;

[0022] S202: sputtering a preset metal coating on the cleaned substrate to form a metal bonding layer, wherein the preset metal coating comprises at least one of molybdenum and titanium, and the thickness of the metal bonding layer is 50-200 nm;

[0023] S203: forming a via pattern by performing a laser writing process on the metal bonding layer;

[0024] S204: dry-etching the via pattern with a fluorine-containing gas to form a clear metallized via.

[0025] Furthermore, the step of premixing the barium titanate and the functional components to obtain the barium titanate-based adhesive comprises:

[0026] S211: placing barium titanate and solid additives in the functional components in a vacuum dryer to dry and mix;

[0027] S212: placing the barium titanate in a mixing device, and gradually adding the additives in the functional component under continuous shear force, and monitoring the dynamic viscosity using a rheometer to ensure that the viscosity is within a preset viscosity range, wherein the preset viscosity range is 200-600 cP and the mixing time is 30-50 minutes;

[0028] S213: The mixed barium titanate-based mixture is transferred to an environment of 10-25° C. for cooling to obtain a barium titanate-based adhesive.

[0029] Furthermore, the step of mounting the chip to be mounted in the mounting cavity in the vacuum chamber and spot-coating a barium titanate-based adhesive around the chip to be mounted to form a dam structure around the chip to be mounted includes:

[0030] S221: Evacuate the vacuum chamber to 10 -3 ~10 -5 Pa, to degas the barium titanate-based glue;

[0031] S222: Install the chip to be mounted in the mounting cavity, and gradually apply barium titanate-based glue along a preset trajectory on the edge area of ​​the chip to be mounted using a precision dispensing device, controlling the dispensing rate to be 0.1-0.5 mL / min, and maintaining the height of the dispensing needle of the precision dispensing device from the substrate surface to be 50-150 μm. During the dispensing process, the ambient temperature in the cavity is maintained at 20-30° C.

[0032] S223: Transfer the chip and substrate combination after the spot coating to an inert gas environment, control the ambient humidity to be lower than 10% RH, and let it stand for 10 to 30 minutes to keep the morphology of the barium titanate-based glue stable and form a dam structure surrounding the chip to be mounted.

[0033] Furthermore, the functional components include a coupling agent, a rheology modifier and a solvent;

[0034] The coupling agent is a mixture of one or more of methylsilane, vinylsilane or triethoxytitanium;

[0035] The rheology modifier is a mixture of one or more of fatty acid esters, polyvinyl alcohol or polyacrylate;

[0036] The solvent is a mixture of one or more of isopropyl alcohol, ethyl acetate or butanone;

[0037] Among them, in the barium titanate-based glue, calculated by mass percentage, the coupling agent accounts for 15-20%, the rheology modifier accounts for 5-10%, the solvent accounts for 25-30%, and the balance is barium titanate.

[0038] Furthermore, the step of connecting the electrode layer to the metallized path and injecting the barium titanate-based paste inside the dam structure includes:

[0039] S411: Connecting the electrode layer and the metallized path by laser melting;

[0040] S412: injecting the barium titanate-based paste into the central area of ​​the dam structure at a preset injection rate, and applying ultrasonic vibration to the ceramic substrate;

[0041] S413: When the injected barium titanate-based glue flows to the dam structure, the injection of the barium titanate-based glue is stopped;

[0042] S414: Perform leveling treatment in a low-vibration environment using a leveling device, with a leveling time of 30 to 60 seconds.

[0043] Furthermore, the step of dynamically curing the injected barium titanate-based adhesive and the dam structure comprises:

[0044] S421: heating the barium titanate-based adhesive and the dam structure to 70-90° C. at a first heating rate, and forming a temperature difference from the center of the chip to be mounted to the periphery of the chip to be mounted, wherein the center temperature of the chip to be mounted is greater than the periphery temperature of the chip to be mounted, for 30-60 minutes;

[0045] S422: heating the barium titanate-based adhesive and the dam structure to 120-150° C. at a second heating rate while reducing the temperature difference for 40-70 minutes;

[0046] S423: heating the barium titanate-based glue and the dam structure to 160-180°C at a third heating rate, and applying mechanical vibration with an amplitude of 0.1-0.5mm and a frequency of 60-90Hz to the barium titanate-based glue and the dam structure for 20-30 minutes to uniformly solidify the colloid.

[0047] Furthermore, the S600 includes:

[0048] S601: preparing a preset filler, the preparation steps comprising: selecting 7070 glass and aluminum oxide, placing them in a mixing container at a molar ratio of 1:0.5-0.7, and mixing them using a high-speed stirring device for 10-15 minutes;

[0049] S602: Filling the preset filler between the ceramic substrate and the metal packaging shell;

[0050] S603: placing the structure filled with the preset filler in a sintering furnace, and raising the temperature to 600-700°C at a heating rate of 10-15°C / min under nitrogen protection, and keeping the temperature for 1-2 hours;

[0051] S604: After stopping heating, the temperature is lowered to 200°C at a cooling rate of 5-10°C / min, and then further cooled to room temperature under natural conditions to obtain a sealed high-temperature and pressure-resistant MEMS pressure sensor.

[0052] The present invention further provides a high-temperature, pressure-resistant MEMS pressure sensor, which is implemented using the packaging technology of any of the above high-temperature, pressure-resistant MEMS pressure sensors, and includes a chip to be mounted, a ceramic substrate, and a metal packaging shell, wherein the chip to be mounted is provided with electrodes, the ceramic substrate is formed with a mounting cavity and a metallized path, and the ceramic substrate is provided with a through hole;

[0053] The chip to be mounted is fixedly mounted in the mounting cavity, the electrode is electrically connected to the metallized path via a wire, and the wire passes through the through hole;

[0054] The metal packaging shell covers the chip to be mounted, and the metal packaging shell is fixedly connected to the ceramic substrate.

[0055] Beneficial effects:

[0056] In the present invention, by spot-coating barium titanate-based glue around the chip to be mounted on the MEMS pressure sensor to form a dam structure, and filling the inner side of the dam with barium titanate-based glue, not only the mechanical support between the chip to be mounted and the ceramic substrate is effectively enhanced, but also excellent thermal stability is achieved, maintaining a low thermal expansion coefficient in a high-temperature environment, avoiding structural damage caused by material thermal expansion mismatch, thereby improving the durability and reliability of the sensor under extreme conditions. A metal packaging shell is used to further enhance the pressure resistance and sealing of the sensor. A preset filler is filled between the ceramic substrate and the metal packaging shell, and sintered at a high temperature of 600-700°C to form a high-strength bonding layer between the filler and the packaging shell, thereby improving the airtightness and mechanical stability of the overall package. The double-layer protective structure of barium titanate-based glue and preset filler improves the long-term stability and reliability of the sensor in a high-temperature and high-pressure environment, can effectively buffer the thermal stress in a high-temperature environment, and prevent the sensor from structural deformation or sealing failure due to stress concentration under long-term high temperature and high pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is a schematic diagram of the steps of a packaging technology for a high-temperature and pressure-resistant MEMS pressure sensor of the present invention;

[0058] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0059] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0060] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like, indicating positions or positional relationships, are based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0061] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections, direct connections, or indirect connections through an intermediate medium; they may refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0062] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact via another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0063] Reference Figure 1 The present invention proposes a packaging technology for a high-temperature and pressure-resistant MEMS pressure sensor, comprising:

[0064] S100: providing a chip to be mounted with a MEMS pressure sensor, depositing a passivation layer and a protection layer on the surface of the chip to be mounted in sequence, and sputtering an electrode layer in the electrode region of the chip to be mounted;

[0065] In step S100, a chip to be mounted with a MEMS pressure sensor is provided, and a passivation layer and a protective layer are sequentially deposited on its surface to enhance the chip's corrosion resistance and physical protection against the external environment, especially its stability in high temperature and high pressure environments. The excellent chemical stability and high-temperature oxidation resistance of the passivation layer can effectively prevent oxidation or contamination of the chip surface, while the protective layer has stronger electrical insulation and thermal stability, ensuring the safety of the chip during long-term use. After the deposition of the passivation and protective layers is completed, the electrode area of ​​the chip is sputtered to form an electrode layer. The electrode layer can use a high-temperature stable metal, and the sputtering process can evenly cover the electrode area to ensure the reliability of electrical contact and provide stable conductive performance.

[0066] S200: Providing a high-temperature co-fired ceramic substrate, wherein a mounting cavity is formed on the ceramic substrate, and sputtering a preset metal coating on the surface of the ceramic substrate to form a metallized path;

[0067] In step S200, a high-temperature co-fired ceramic substrate is provided, and a mounting cavity is formed on the substrate surface for subsequent chip installation. A predetermined metal coating is deposited on the substrate surface through a sputtering process, forming a metallized path. The metal coating can be made of materials such as molybdenum or titanium, and is uniformly deposited on the surface of the ceramic substrate through methods such as magnetron sputtering or reactive sputtering to form a metallized path. The metallized path can electrically connect to the chip electrode area, ensuring stable signal transmission and providing good thermal conductivity to adapt to high-temperature operating environments.

[0068] S300: premixing barium titanate and functional components to obtain barium titanate-based adhesive, mounting the chip to be mounted in the mounting cavity in a vacuum chamber, and spot-coating the barium titanate-based adhesive around the chip to be mounted to form a dam structure surrounding the chip to be mounted;

[0069] In step S300, barium titanate and other functional components are premixed to form a barium titanate-based adhesive. The barium titanate-based adhesive serves as a fixing material and a primary thermally stable protective material for the MEMS pressure sensor chip package. The chip is mounted in the mounting cavity of the substrate in a vacuum chamber, and the barium titanate-based adhesive is spot-coated around the chip to form a dam structure. The barium titanate-based adhesive surrounding the chip can provide a container for the subsequent injection of the barium titanate-based adhesive. The barium titanate-based adhesive and the dam structure of the barium titanate-based adhesive can strengthen the chip from being affected by external physical stress in a high-temperature environment and enhance the bonding force between the chip and the substrate. The barium titanate-based adhesive has high-temperature stability and can withstand temperatures above 600°C. It also has good sealing properties, preventing contaminants from the external environment from invading the interior of the sensor.

[0070] S400: connecting the electrode layer to the metallized path, injecting the barium titanate-based glue into the inner side of the dam structure, and dynamically curing the injected barium titanate-based glue and the dam structure;

[0071] In step S400, the chip's electrode layer is connected to the metallized path through methods such as hot pressing welding or laser melting to firmly connect the electrode layer and the metallized path, ensuring that the transmission of electrical signals is not affected by the high temperature environment. Subsequently, barium titanate-based glue is injected into the inner side of the dam structure and a dynamic multi-stage curing process is performed. This curing process is carried out at a controlled temperature to ensure that the barium titanate-based glue completely fills the dam structure, while also improving the mechanical strength and stability of the cured glue, allowing it to maintain long-term reliability in high-temperature and high-pressure environments.

[0072] S500: Providing a metal packaging shell, plating a preset metal layer on the surface of the metal packaging shell, and covering the ceramic substrate with the metal packaging shell;

[0073] In step S500, the metal package housing can be made of materials such as stainless steel or titanium alloy, which exhibit excellent mechanical strength and corrosion resistance. A predetermined metal layer is plated onto the surface of the metal package housing. The metal layer is made of a high-temperature stable metal to ensure that the package housing can withstand operating conditions in extremely high-temperature and high-pressure environments. The metal package housing tightly covers the ceramic substrate, protecting the internal chip and interconnects, ensuring long-term stable operation in high-temperature and high-pressure environments.

[0074] S600: Filling a preset filler between the ceramic substrate and the metal packaging shell, and sintering at 600-700° C. to obtain a sealed high-temperature and pressure-resistant MEMS pressure sensor, and cooling the high-temperature and pressure-resistant MEMS pressure sensor to room temperature at a preset cooling rate.

[0075] In step S600, a pre-set filler is placed between the ceramic substrate and the metal package housing. The pre-set filler is made of a material with a low thermal expansion coefficient to fill the package gap and provide additional mechanical support. A certain formula of additives is added to achieve better thermal stability. The packaged MEMS pressure sensor is then sintered at a temperature between 600°C and 700°C. This sintering process further strengthens the bond between the metallized path and the ceramic substrate, ensuring the density and stability of the overall package. Finally, the entire sensor is cooled to room temperature at a pre-set cooling rate to ensure that no stress is generated during the cooling process, preventing cracking or deformation of the packaging material.

[0076] In summary, by dotting a barium titanate-based adhesive around the MEMS pressure sensor chip to form a dam structure and then filling the inner portion of the dam with the barium titanate-based adhesive, the structure not only effectively strengthens the mechanical support between the chip and substrate but also provides excellent thermal stability, maintaining a low thermal expansion coefficient in high-temperature environments and preventing structural damage caused by material thermal expansion mismatch, thereby improving the sensor's durability and reliability under extreme conditions. A metal encapsulation further enhances the sensor's pressure resistance and sealing properties. A pre-set filler is placed between the substrate and the metal encapsulation, and sintered at 600-700°C to form a high-strength bond between the filler and the encapsulation, improving the overall package's airtightness and mechanical stability. This dual-layer protective structure of barium titanate-based adhesive and pre-set filler enhances the sensor's long-term stability and reliability in high-temperature and high-pressure environments. It effectively buffers thermal stress in high-temperature environments, preventing structural deformation or seal failure caused by stress concentration under long-term high-temperature and high-pressure conditions.

[0077] In one embodiment, the steps of providing a chip to be mounted with a MEMS pressure sensor, sequentially depositing a passivation layer and a protective layer on the surface of the chip to be mounted, and sputtering an electrode layer in the electrode region of the chip to be mounted, include:

[0078] S101: Providing a MEMS pressure sensor chip based on a silicon-oxide-silicon structure, wherein the MEMS pressure sensor chip is formed with a plurality of electrode regions;

[0079] The MEMS pressure sensor chip features multiple electrode areas, which are critical for subsequent electrical connections and ensure the sensor's signal acquisition and transmission capabilities. The chip, based on a silicon-oxide-silicon structure, is capable of providing highly accurate pressure measurements. Its SOI structure provides excellent mechanical strength and stability, ensuring long-term reliability in high-temperature and high-pressure environments.

[0080] S102: forming a passivation layer on the surface of the MEMS pressure sensor chip by plasma enhanced chemical vapor deposition of silicon nitride, and depositing a protective layer on the passivation layer by physical vapor deposition of silicon oxide;

[0081] A passivation layer is deposited on the surface of the MEMS pressure sensor chip using a plasma-enhanced chemical vapor deposition (PECVD) process using silicon nitride (Si3N4). This layer protects the chip surface from external environmental influences (such as moisture and chemical corrosion), thereby improving the chip's lifespan and stability. Furthermore, a protective layer of silicon oxide (SiO2) is deposited on top of the passivation layer using a physical vapor deposition (PVD) process. This provides enhanced electrical insulation, preventing short circuits between the electrodes and external circuits. It also exhibits excellent thermal stability and durability in high-temperature operating environments.

[0082] S103: performing pattern etching on the protection layer and the passivation layer based on the electrode region to expose the electrode region;

[0083] Based on the electrode area of ​​the chip to be mounted, the protective layer and passivation layer are finely etched and patterned. This can be achieved through photolithography and chemical development methods, exposing the electrode area. The etching accuracy directly affects the subsequent electrode sputtering process. The etch patterning process exposes the electrode area and ensures a good electrical connection between the electrode and the metallization path.

[0084] S104: sputtering the exposed electrode area using one of gold, platinum, or nickel to form an electrode layer, and making the thickness of the electrode layer equal to the sum of the thickness of the protective layer and the passivation layer;

[0085] Using a metal such as gold, platinum, or nickel, a sputtering process uniformly deposits the metal on the exposed electrode area to form an electrode layer. The thickness of this electrode layer is equal to the sum of the thicknesses of the protective layer and the passivation layer. This ensures a balance between the electrode layer, the protective layer, and the passivation layer, enabling the electrode layer to provide stable electrical contact. The equal values ​​remain within a certain range, with a certain degree of deviation allowed. The sputtering process ensures that the metal electrode layer evenly covers the electrode area and has strong adhesion to the chip surface, ensuring reliable electrical connection in high-temperature environments.

[0086] S105: curing and connecting the electrode layer and the electrode region at 300-400° C., and annealing at 400-450° C. for 0.5-1 hour under nitrogen protection.

[0087] The electrode layer is connected to the electrode area by curing, and the curing treatment is carried out at a temperature of 300~400℃ to ensure a tight bond between the electrode layer and the chip electrode area. At this temperature, the electrode layer can form a strong physical connection with the electrode area, improving the stability and conductivity of the connection. Then, annealing treatment is carried out in nitrogen protection, and the annealing temperature is set to 400~450℃ and maintained for 0.5~1 hour. The purpose of annealing is to eliminate the internal stress that may be generated due to temperature changes during the curing process, improve the adhesion between the electrode layer and the chip surface, and enable the electrode layer to maintain stable electrical properties for a long time in a high temperature environment.

[0088] In one embodiment, the step of providing a high-temperature co-fired ceramic substrate having a mounting cavity formed thereon and sputtering a predetermined metal coating on the surface of the ceramic substrate to form a metallized path includes:

[0089] S201: providing a high-temperature co-fired ceramic substrate, placing the ceramic substrate in a plasma cleaning device, and treating the ceramic substrate for 5 to 10 minutes using a mixed gas of argon and nitrogen as a cleaning medium, wherein the power density of the plasma cleaning device is set to 0.25 to 0.45 W / cm², and the flow ratio of argon to oxygen is 3 to 5:1;

[0090] High-temperature co-fired ceramic substrates offer high-temperature stability and a low thermal expansion coefficient, making them suitable for use in high-temperature operating environments. The substrates are placed in a plasma cleaning system and cleaned using a mixture of argon and nitrogen as the cleaning medium. The cleaning time is 5 to 10 minutes, with the plasma cleaning system power density set at 0.25 to 0.45 W / cm² and the argon to nitrogen flow ratio set at 3 to 5:1. The plasma cleaning process effectively removes organic matter and microcontaminants from the substrate surface, ensuring that the metal coating adheres firmly to the substrate surface. This process ensures the uniformity and stability of the subsequent metal coating, providing a high-quality substrate for the deposition of metallized vias.

[0091] S202: sputtering a preset metal coating on the cleaned substrate to form a metal bonding layer, wherein the preset metal coating comprises at least one of molybdenum and titanium, and the thickness of the metal bonding layer is 50-200 nm;

[0092] The cleaned substrate is sputtered with a pre-prepared metallic coating to form a metal bonding layer. The metallic coating comprises at least one of molybdenum and titanium, exhibiting excellent thermal stability and adhesion to the ceramic substrate. The sputtering process deposits the metal bonding layer onto the substrate surface, with a thickness controlled between 50 and 200 nm. This process ensures a uniform, bubble-free metal coating. The molybdenum and titanium coating not only enhances the bonding strength between the metal and the ceramic substrate but also offers high heat resistance, maintaining stability in high-temperature environments.

[0093] S203: forming a via pattern by performing a laser writing process on the metal bonding layer;

[0094] Laser writing technology uses a laser beam to scan the metal bonding layer according to a predetermined circuit pattern. By precisely controlling the laser power and scanning speed, unwanted metal areas are removed, forming the desired via pattern. This process enables high-precision patterning, ensuring precise control of metal vias at the micron level and meeting the electrical stability requirements in high-temperature environments. It not only avoids some of the complex steps in traditional photolithography, but also provides higher pattern accuracy and reduces production errors.

[0095] S204: dry-etching the via pattern with a fluorine-containing gas to form a clear metallized via.

[0096] The via pattern is dry-etched using a fluorine-containing gas to further refine the metallized vias. The fluorine-containing etching gas used can be SF6 or CF4. This gas effectively removes metal areas not removed by the laser writing process, while precisely etching the metal coating to form clear metallized vias. Dry etching not only achieves high-precision etching but also avoids the contamination issues that can occur with wet etching. By controlling the etching time and gas flow rate, the metallized vias can be ensured to have sharp edges and uniform widths, thereby guaranteeing the reliability and stability of the electrical connection.

[0097] In one embodiment, the step of premixing barium titanate and functional components to obtain a barium titanate-based adhesive comprises:

[0098] S211: placing barium titanate and solid additives in the functional components in a vacuum dryer to dry and mix;

[0099] The barium titanate and solid additives in the functional components are dried in a vacuum dryer to ensure that all solid materials are completely free of moisture and any other moisture that may affect the subsequent mixing process before being added to the mixture. Drying in a vacuum environment effectively prevents the effects of moisture on material properties, especially the barium titanate particles, thereby ensuring the stability and high-temperature performance of the barium titanate in subsequent steps. After drying, the mixed materials are evenly mixed, ensuring that all components are fully dispersed in the initial stage.

[0100] S212: placing the barium titanate in a mixing device, and gradually adding the additives in the functional component under continuous shear force, and monitoring the dynamic viscosity using a rheometer to ensure that the viscosity is within a preset viscosity range, wherein the preset viscosity range is 200 to 600 cP, and the mixing time is 30 to 50 minutes;

[0101] The dried barium titanate mixture is placed in a mixing apparatus. Under continuous shear force, various additives from the functional components, including solvents, crosslinkers, and flow improvers, are gradually added. By applying appropriate shear force, the components are fully and evenly distributed during the mixing process, ensuring a homogeneous barium titanate-based adhesive. During this process, a rheometer is used to monitor the dynamic viscosity of the mixture in real time, ensuring that the viscosity remains within the range of 200-600 cP. The use of a rheometer enables precise control of viscosity changes, preventing excessively high or low viscosity from affecting subsequent processes. The mixing time is set to 30-50 minutes to ensure that the additives are fully dissolved and react with the barium titanate, forming a high-quality barium titanate-based adhesive.

[0102] S213: The mixed barium titanate-based mixture is transferred to an environment of 10-25° C. for cooling to obtain a barium titanate-based glue.

[0103] The mixed barium titanate mixture is transferred to a 10-25°C environment for cooling. After this cooling process, the final barium titanate adhesive is obtained. During the cooling process, the material's viscosity gradually stabilizes, ensuring it maintains ideal working conditions at room temperature, facilitating subsequent injection and curing operations. By controlling temperature fluctuations during the cooling process, instability in the colloid properties caused by temperature fluctuations can be avoided, ensuring that the colloid does not experience fluidity changes or precipitation during the encapsulation process, thereby maintaining its long-term stability and reliability.

[0104] In one embodiment, the step of mounting the chip to be mounted in the mounting cavity in the vacuum chamber and spot-coating a barium titanate-based adhesive around the chip to be mounted to form a dam structure around the chip to be mounted includes:

[0105] S221: Evacuate the vacuum chamber to 10 -3 ~10 -5 Pa, to degas the barium titanate-based glue;

[0106] S222: Install the chip to be mounted in the mounting cavity, and gradually apply barium titanate-based glue along a preset trajectory on the edge area of ​​the chip to be mounted using a precision dispensing device, controlling the dispensing rate to be 0.1-0.5 mL / min, and maintaining the height of the dispensing needle of the precision dispensing device from the substrate surface to be 50-150 μm. During the dispensing process, the ambient temperature in the cavity is maintained at 20-30° C.

[0107] S223: Transfer the chip and substrate combination after the spot coating to an inert gas environment, control the ambient humidity to be lower than 10% RH, and let it stand for 10 to 30 minutes to keep the morphology of the barium titanate-based glue stable and form a dam structure surrounding the chip to be mounted.

[0108] In the above embodiment, the vacuum chamber is evacuated to a temperature of 10 -3 ~10 -5 Pa vacuum state, so as to degas the barium titanate-based glue, remove bubbles in the colloid, avoid bubble defects in the subsequent curing process, and thus improve the sealing and uniformity of the final package. Avoid the performance degradation of the barium titanate-based glue during the filling application stage due to bubbles affecting its fluidity and adhesion. The chip to be installed is installed in the installation cavity, and a precision dispensing device is used to gradually apply the barium titanate-based glue along a preset track in the edge area of ​​the chip. The dispensing rate is controlled to be set to 0.1~0.5mL / min, and the height between the dispensing needle and the substrate surface is maintained between 50~150μm to control the uniformity of the glue layer, and the ambient temperature in the cavity is maintained at 2030℃ to ensure that the barium titanate-based glue has appropriate fluidity during dispensing, thereby forming a uniform dam structure to prevent the external environment from affecting the importance of the chip and its long-term performance.

[0109] The chip and substrate combination after spot coating is transferred to an inert gas environment with the ambient humidity controlled below 10% RH and allowed to stand for 10 to 30 minutes to ensure that the morphology of the barium titanate-based adhesive remains stable. This standing step further reduces the risk of volatilization and shrinkage of the colloid by controlling the low humidity environment, ensuring the stability of the dam structure formed before hardening and avoiding deformation or cracking.

[0110] In one embodiment, the functional components include a coupling agent, a rheology modifier, and a solvent;

[0111] The coupling agent is a mixture of one or more of methylsilane, vinylsilane or triethoxytitanium;

[0112] The rheology modifier is a mixture of one or more of fatty acid esters, polyvinyl alcohol or polyacrylate;

[0113] The solvent is a mixture of one or more of isopropyl alcohol, ethyl acetate or butanone;

[0114] Among them, in the barium titanate-based glue, calculated by mass percentage, the coupling agent accounts for 15-20%, the rheology modifier accounts for 5-10%, the solvent accounts for 25-30%, and the balance is barium titanate.

[0115] In the above embodiments, the preparation of the barium titanate-based adhesive includes adding multiple functional components to enhance its performance, including a coupling agent, a rheology modifier, and a solvent.

[0116] Specifically, the coupling agent is a mixture of one or more methylsilane, vinylsilane, or triethoxytitanium. The coupling agent can form an effective chemical bond with the barium titanate particles, improving the adhesion between the barium titanate-based adhesive and the substrate, and enhancing the mechanical properties and stability of the material. The rheology modifier is a mixture of one or more fatty acid esters, polyvinyl alcohol, or polyacrylates, which can effectively adjust the fluidity and viscosity of the barium titanate-based adhesive, making it easier to pour and form during application to meet specific usage conditions. The solvent is a mixture of one or more isopropyl alcohol, ethyl acetate, or butanone. The choice of solvent can promote uniform dispersion and fluidity of the colloid while maintaining an appropriate viscosity, ensuring the stability of the mixture during filling.

[0117] Calculated by mass percentage, the coupling agent accounts for 15-20%, the rheology modifier accounts for 5-10%, the solvent accounts for 25-30%, and the balance is barium titanate. The barium titanate-based glue formed after sufficient mixing of this ratio has good fluidity, enhanced adhesion performance and excellent high-temperature resistance, which enables it to perform well in the packaging of high-temperature and pressure-resistant MEMS pressure sensors, and improves the stability and reliability of the sensor under extreme conditions.

[0118] In one embodiment, the step of connecting the electrode layer to the metallization path and injecting the barium titanate-based paste inside the dam structure includes:

[0119] S411: Connecting the electrode layer and the metallized path by laser melting;

[0120] S412: injecting the barium titanate-based paste into the central area of ​​the dam structure at a preset injection rate, and applying ultrasonic vibration to the ceramic substrate;

[0121] S413: When the injected barium titanate-based glue flows to the dam structure, the injection of the barium titanate-based glue is stopped;

[0122] S414: Perform leveling treatment in a low-vibration environment using a leveling device, with a leveling time of 30 to 60 seconds.

[0123] In the above embodiment, the electrode layer and the metallized path are connected by laser melting. A high-precision laser beam is used to rapidly heat the contact area between the electrode layer and the metallized path, causing them to melt and connect in a local area to ensure a stable and conductive electrical contact, thereby improving the signal transmission reliability of the sensor. Barium titanate-based glue is injected into the central area of ​​the dam structure at a preset injection rate, and ultrasonic vibration is applied to the substrate during this process. This can effectively promote the flow of the barium titanate-based glue, ensuring that it fully fills the surrounding gaps, avoiding the formation of voids during the glue injection process, making the glue flow evenly, increasing the contact area with the dam structure, and improving the bonding effect of subsequent curing. The preset injection rate can be set between 0.5 ml and 2 ml per minute to ensure the uniformity and stability of the glue injection.

[0124] When the injected barium titanate-based glue flows and contacts the dam structure, the injection of the barium titanate-based glue is stopped to ensure that the glue is naturally flat within the range of the dam, while avoiding overflow or unevenness caused by excessive injection. Finally, a leveling process is performed using a leveling device in a low-vibration environment for 30 to 60 seconds. This allows the palladium titanate-based glue to form a smooth and uniform surface under the action of gravity and surface tension, ensuring the morphological stability of the dam structure and providing good conditions for subsequent curing.

[0125] In one embodiment, the step of dynamically curing the injected barium titanate-based adhesive and the dam structure comprises:

[0126] S421: heating the barium titanate-based adhesive and the dam structure to 70-90° C. at a first heating rate, and forming a temperature difference from the center of the chip to be mounted to the periphery of the chip to be mounted, wherein the center temperature of the chip to be mounted is greater than the periphery temperature of the chip to be mounted, for 30-60 minutes;

[0127] S422: heating the barium titanate-based adhesive and the dam structure to 120-150° C. at a second heating rate while reducing the temperature difference for 40-70 minutes;

[0128] S423: heating the barium titanate-based glue and the dam structure to 160-180°C at a third heating rate, and applying mechanical vibration with an amplitude of 0.1-0.5mm and a frequency of 60-90Hz to the barium titanate-based glue and the dam structure for 20-30 minutes to uniformly solidify the colloid.

[0129] In the above embodiment, the barium titanate-based glue and the dam structure are heated to 70-90°C at a heating rate of 1.5-2.5°C / min, and the power distribution of the heating element is controlled so that the temperature of the central area of ​​the chip is 5-10°C higher than the temperature of the peripheral area of ​​the chip; after reaching the target temperature, the temperature and temperature gradient are maintained for 30-60 minutes.

[0130] The barium titanate-based glue and the dam structure are heated to 120-150°C at a heating rate of 2.0-3.0°C / min. During the heating process, the temperature difference between the central area of ​​the chip and the peripheral area of ​​the chip is gradually reduced, so that the temperature gradient is gradually reduced from the initial 5-10°C to 0-4°C. When the temperature reaches 120-150°C, it lasts for 40 to 70 minutes.

[0131] The barium titanate-based glue and the dam structure are heated from 120-150°C to 160-180°C at a heating rate of 1.0-2.0°C / min. During the heating process, mechanical vibration with an amplitude of 0.1-0.5mm and a frequency of 60-90Hz is applied to the barium titanate-based glue and the dam structure. When the temperature reaches 160-180°C, the vibration is maintained for 20-30 minutes. At the same time, the curing degree of the barium titanate-based glue is monitored in real time, and the holding time is adjusted according to the curing degree.

[0132] In one embodiment, the S600 includes:

[0133] S601: preparing a preset filler, the preparation steps comprising: selecting 7070 glass and aluminum oxide, placing them in a mixing container at a molar ratio of 1:0.5-0.7, and mixing them using a high-speed stirring device for 10-15 minutes;

[0134] S602: Filling the preset filler between the ceramic substrate and the metal packaging shell;

[0135] S603: placing the structure filled with the preset filler in a sintering furnace, and raising the temperature to 600-700°C at a heating rate of 10-15°C / min under nitrogen protection, and keeping the temperature for 1-2 hours;

[0136] S604: After stopping heating, the temperature is lowered to 200°C at a cooling rate of 5-10°C / min, and then further cooled to room temperature under natural conditions to obtain a sealed high-temperature and pressure-resistant MEMS pressure sensor.

[0137] In the above embodiment, by selecting 7070 glass and alumina as fillers and strictly controlling their molar ratio and mixing time, the uniformity and stability of the filler are ensured. The preset filler is filled between the substrate and the metal packaging shell. After a high-temperature sintering process, a strong chemical bond can be formed between the filler and the substrate and the metal packaging shell, thereby improving the sealing performance and pressure resistance of the sensor. The heating rate is 10-15°C / minute, and the temperature is raised to 600-700°C and kept warm for 1-2 hours to achieve sintering and curing of the filler, ensuring a good combination of 7070 glass and alumina, and improving the overall strength and high-temperature resistance. In addition, the sintering process under nitrogen protection effectively avoids oxidation of the filler at high temperatures, ensuring the long-term stability and reliability of the sensor. After stopping heating, the temperature is lowered to 200°C at a cooling rate of 5-10°C / minute, and then continued to cool to room temperature under natural conditions to ensure the stability of the filler curing process, avoid stress concentration and cracking, and further improve the overall performance of the sensor, thereby completing the packaging of the high-temperature and pressure-resistant MEMS pressure sensor, ensuring its good sealing, strength and long-term stability in high-temperature and high-pressure environments.

[0138] The present invention further provides a high-temperature, pressure-resistant MEMS pressure sensor, which is implemented using the packaging technology of any of the above high-temperature, pressure-resistant MEMS pressure sensors, and includes a chip to be mounted, a ceramic substrate, and a metal packaging shell, wherein the chip to be mounted is provided with electrodes, the ceramic substrate is formed with a mounting cavity and a metallized path, and the ceramic substrate is provided with a through hole;

[0139] The chip to be mounted is fixedly mounted in the mounting cavity, the electrode is electrically connected to the metallized path via a wire, and the wire passes through the through hole;

[0140] The metal packaging shell covers the chip to be mounted, and the metal packaging shell is fixedly connected to the ceramic substrate.

[0141] In the above embodiment, the high-temperature and pressure-resistant MEMS pressure sensor includes a chip to be installed, a ceramic substrate and a metal packaging shell, wherein electrodes are provided on the chip, a mounting cavity and a metallized path are formed on the substrate, and a through-hole is provided on the substrate. In this structure, the chip is fixedly installed in the mounting cavity, the electrodes and the metallized path are electrically connected through wires, and the wires pass through the through-holes on the substrate to ensure the transmission and stability of the electrical signal. The metal packaging shell covers the chip and is fixedly connected to the substrate to form a good protection and sealing effect. By adopting this packaging structure, the reliability and stability of the MEMS pressure sensor in a high-temperature and high-pressure environment can be effectively improved. The electrical connection between the chip's electrodes and the metallized path is completed by wires to ensure the accuracy of signal transmission, and the wires passing through the through-holes effectively avoid interference between circuits.

[0142] The metal packaging shell covers the chip, that is, it encapsulates the chip inside, and is fixedly connected to the substrate. The protective function of the metal packaging shell can protect the chip from the influence of the external environment, improve its durability under extreme conditions, and effectively improve the long-term stability of the sensor under harsh working conditions, ensuring its reliable use in high-temperature and high-pressure environments such as aerospace, oil exploration, etc., thereby achieving excellent use results.

[0143] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A packaging method for a high-temperature and pressure-resistant MEMS pressure sensor, characterized in that: include: S100: providing a chip to be mounted with a MEMS pressure sensor, depositing a passivation layer and a protection layer on the surface of the chip to be mounted in sequence, and sputtering an electrode layer in the electrode region of the chip to be mounted; S200: Providing a high-temperature co-fired ceramic substrate, wherein a mounting cavity is formed on the ceramic substrate, and sputtering a preset metal coating on the surface of the ceramic substrate to form a metallized path; S300: premixing barium titanate and functional components to obtain barium titanate-based adhesive, mounting the chip to be mounted in the mounting cavity in a vacuum chamber, and spot-coating the barium titanate-based adhesive around the chip to be mounted to form a dam structure surrounding the chip to be mounted; S400: connecting the electrode layer to the metallized path, injecting the barium titanate-based glue into the inner side of the dam structure, and dynamically curing the injected barium titanate-based glue and the dam structure; S500: Providing a metal packaging shell, plating a preset metal layer on the surface of the metal packaging shell, and covering the ceramic substrate with the metal packaging shell; S600: Filling a predetermined filler between the ceramic substrate and the metal packaging shell, and sintering at 600-700° C. to obtain a sealed high-temperature and pressure-resistant MEMS pressure sensor, and cooling the high-temperature and pressure-resistant MEMS pressure sensor to room temperature at a predetermined cooling rate; The functional components include a coupling agent, a rheology modifier and a solvent; The coupling agent is a mixture of one or more of methylsilane, vinylsilane or triethoxytitanium; The rheology modifier is a mixture of one or more of fatty acid esters, polyvinyl alcohol or polyacrylate; The solvent is a mixture of one or more of isopropyl alcohol, ethyl acetate or butanone; Wherein, in the barium titanate-based adhesive, calculated by mass percentage, the coupling agent accounts for 15-20%, the rheology modifier accounts for 5-10%, the solvent accounts for 25-30%, and the balance is barium titanate; The preparation steps of the preset filler include: selecting 7070 glass and aluminum oxide, placing them in a mixing container at a molar ratio of 1:0.5-0.7, and mixing them using a high-speed stirring device for 10-15 minutes.

2. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 1, characterized in that: The step of providing a chip to be mounted with a MEMS pressure sensor, depositing a passivation layer and a protective layer on the surface of the chip to be mounted in sequence, and sputtering an electrode layer in the electrode area of ​​the chip to be mounted comprises: S101: Providing a MEMS pressure sensor chip based on a silicon-oxide-silicon structure, wherein the MEMS pressure sensor chip is formed with a plurality of electrode regions; S102: forming a passivation layer on the surface of the MEMS pressure sensor chip by plasma enhanced chemical vapor deposition of silicon nitride, and depositing a protective layer on the passivation layer by physical vapor deposition of silicon oxide; S103: performing pattern etching on the protection layer and the passivation layer based on the electrode region to expose the electrode region; S104: sputtering the exposed electrode area using one of gold, platinum, or nickel to form an electrode layer, and making the thickness of the electrode layer equal to the sum of the thickness of the protective layer and the passivation layer; S105: curing and connecting the electrode layer and the electrode region at 300-400° C., and annealing at 400-450° C. for 0.5-1 hour under nitrogen protection.

3. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 1, characterized in that: The step of providing a high-temperature co-fired ceramic substrate having a mounting cavity formed thereon and sputtering a preset metal coating on the surface of the ceramic substrate to form a metallized path comprises: S201: providing a high-temperature co-fired ceramic substrate, placing the ceramic substrate in a plasma cleaning device, and treating the ceramic substrate for 5 to 10 minutes using a mixed gas of argon and nitrogen as a cleaning medium, wherein the power density of the plasma cleaning device is set to 0.25 to 0.45 W / cm², and the flow ratio of argon to oxygen is 3 to 5:1; S202: sputtering a preset metal coating on the cleaned substrate to form a metal bonding layer, wherein the preset metal coating comprises at least one of molybdenum and titanium, and the thickness of the metal bonding layer is 50-200 nm; S203: forming a via pattern by performing a laser writing process on the metal bonding layer; S204: dry-etching the via pattern with a fluorine-containing gas to form a clear metallized via.

4. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 1, characterized in that: The step of premixing barium titanate and functional components to obtain a barium titanate-based adhesive comprises: S211: placing barium titanate and solid additives in the functional components in a vacuum dryer to dry and mix; S212: placing the barium titanate in a mixing device, gradually adding the additives in the functional component under continuous shear force, and monitoring the dynamic viscosity using a rheometer to ensure that the viscosity is within a preset viscosity range, wherein the preset viscosity range is 200-600 cP and the mixing time is 30-50 minutes; S213: The mixed barium titanate-based mixture is transferred to an environment of 10-25° C. for cooling to obtain a barium titanate-based glue.

5. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 1, characterized in that: The step of mounting the chip to be mounted in the mounting cavity in the vacuum chamber and spot-coating a barium titanate-based adhesive around the chip to be mounted to form a dam structure around the chip to be mounted comprises: S221: Evacuate the vacuum chamber to 10 -3 ~10 -5 Pa, to degas the barium titanate-based glue; S222: Install the chip to be mounted in the mounting cavity, and gradually apply barium titanate-based glue along a preset trajectory on the edge area of ​​the chip to be mounted using a precision dispensing device, controlling the dispensing rate to be 0.1-0.5 mL / min, and maintaining the height of the dispensing needle of the precision dispensing device from the substrate surface to be 50-150 μm. During the dispensing process, the ambient temperature in the cavity is maintained at 20-30° C. S223: Transfer the chip and substrate combination after the spot coating to an inert gas environment, control the ambient humidity to be lower than 10% RH, and let it stand for 10 to 30 minutes to keep the morphology of the barium titanate-based glue stable and form a dam structure surrounding the chip to be mounted.

6. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 1, characterized in that: The step of connecting the electrode layer to the metallized path and injecting the barium titanate-based paste inside the dam structure includes: S411: Connecting the electrode layer and the metallized path by laser melting; S412: injecting the barium titanate-based paste into the central area of ​​the dam structure at a preset injection rate, and applying ultrasonic vibration to the ceramic substrate; S413: When the injected barium titanate-based glue flows to the dam structure, the injection of the barium titanate-based glue is stopped; S414: Perform leveling treatment in a low-vibration environment using a leveling device, with a leveling time of 30 to 60 seconds.

7. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 1, characterized in that: The step of dynamically curing the injected barium titanate-based adhesive and the dam structure comprises: S421: heating the barium titanate-based adhesive and the dam structure to 70-90° C. at a first heating rate, and forming a temperature difference from the center of the chip to be mounted to the periphery of the chip to be mounted, wherein the center temperature of the chip to be mounted is greater than the periphery temperature of the chip to be mounted, for 30-60 minutes; S422: heating the barium titanate-based adhesive and the dam structure to 120-150° C. at a second heating rate while reducing the temperature difference for 40-70 minutes; S423: heating the barium titanate-based glue and the dam structure to 160-180°C at a third heating rate, and applying mechanical vibration with an amplitude of 0.1-0.5mm and a frequency of 60-90Hz to the barium titanate-based glue and the dam structure for 20-30 minutes to uniformly solidify the colloid.

8. The packaging method of a high-temperature and pressure-resistant MEMS pressure sensor according to claim 7, characterized in that: The S600 includes: S602: Filling the preset filler between the ceramic substrate and the metal packaging shell; S603: placing the structure filled with the preset filler in a sintering furnace, and raising the temperature to 600-700°C at a heating rate of 10-15°C / min under nitrogen protection, and keeping the temperature for 1-2 hours; S604: After stopping heating, the temperature is lowered to 200°C at a cooling rate of 5-10°C / min, and then further cooled to room temperature under natural conditions to obtain a sealed high-temperature and pressure-resistant MEMS pressure sensor.

9. A high-temperature and pressure-resistant MEMS pressure sensor, characterized in that: The packaging method of the high-temperature and pressure-resistant MEMS pressure sensor according to any one of claims 1 to 8 is adopted, comprising a chip to be mounted, a ceramic substrate, and a metal packaging shell, wherein the chip to be mounted is provided with electrodes, the ceramic substrate is formed with a mounting cavity and a metallized path, and the ceramic substrate is provided with a through hole; The chip to be mounted is fixedly mounted in the mounting cavity, the electrode is electrically connected to the metallized path via a wire, and the wire passes through the through hole; The metal packaging shell covers the chip to be mounted, and the metal packaging shell is fixedly connected to the ceramic substrate.

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