High-temperature-resistant silicon piezoresistive pulsating pressure sensor and manufacturing method thereof

Abstract

The invention relates to the technical field of MEMS sensors, in particular to a high-temperature-resistant silicon piezoresistive pulsating pressure sensor and a manufacturing method thereof. After being rigidly sealed with a glass lining, the top silicon of the PN junction-free SOI silicon piezoresistive pressure sensitive chip of the sensor is inversely packaged in a high-temperature-resistant small-caliber tube seat inner column in a solid state, and the PN junction-free SOI pressure sensitive chip has the advantages and characteristics of no liquid, no movable piece, stable thermal characteristic matching, high inherent frequency, small caliber and light weight. The high-temperature-resistant silicon piezoresistive pulsating pressure sensor can make up and break through congenital shortages and limitations of environmental adaptability of a conventional silicon piezoresistive pressure sensor, and is not only suitable for pulsating pressure measurement, but also universal for static pressure measurement. The method can stably, robustly and reliably measure the gas pressure and the liquid pressure of the monocrystalline silicon under the ideal Young modulus limit temperature of 556 DEG C in situ for a long time.

Description

Technical Field

[0001] The present invention relates to the technical field of MEMS sensors, and in particular to a high temperature resistant silicon piezoresistive pulsating pressure sensor and a manufacturing method thereof. Background Art

[0002] For silicon piezoresistive pressure sensors with PN junction electrical isolation structure, the conventional maximum operating temperature is limited to below 125°C. Affected by the intrinsic limitation that the reverse saturation leakage current of the PN junction increases geometrically with the increase of temperature, when the operating temperature exceeds 125°C, the PN junction electrical isolation function basically fails, causing the sensor output signal signal-to-noise ratio to begin to deteriorate significantly. Silicon piezoresistive pressure sensors without PN junctions filled with pressure transmission fluid cannot adapt to high temperature and pulsating pressure measurement above 180°C due to the viscosity effect of the liquid and thermal expansion and contraction, increased package volume and weight, thermal stability and low natural frequency. The inertia of the liquid under frequent or high-frequency vibration shocks will cause deformation and damage to the sensor structure. The conventional bonding wires for the electrical connection between the sensitive chip and the outside not only require a larger diameter socket, but also its movable characteristics and the limitations of the bonding strength make it difficult for the sensor to adapt to the harsh measurement environment of high temperature and vibration shock.

[0003] To this end, we propose a high temperature resistant silicon piezoresistive pulsating pressure sensor and its manufacturing method. The sensor of the present invention makes up for and breaks through the inherent shortcomings and usage limitations of the above-mentioned conventional silicon piezoresistive pressure sensor. It is not only suitable for the measurement of high-frequency pulsating pressure, but also for general static pressure measurement. It can measure the pressure of gas and liquid below the ideal Young's modulus limit temperature of single crystal silicon of 556°C in a long-term stable, robust and reliable manner. Summary of the invention

[0004] The main purpose of the present invention is to provide a high temperature resistant silicon piezoresistive pulsating pressure sensor and its manufacturing method, which adopts an all-solid-state, inverted stacked packaging structure without moving parts, and has the characteristics of no PN junction, high natural frequency and high packaging surface area efficiency. The high temperature resistant silicon piezoresistive pulsating pressure sensor makes up for and breaks through the inherent shortcomings and usage limitations of conventional silicon piezoresistive pressure sensors. It is not only suitable for measuring pulsating pressure, but also for general static pressure measurement. It can measure the pressure of gas and liquid below the ideal Young's modulus limit temperature of single crystal silicon 556°C in a long-term stable, robust and reliable manner.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A high temperature resistant silicon piezoresistive pulsating pressure sensor, comprising a SOI silicon piezoresistive pressure sensitive chip, a glass liner, a small-diameter tube seat, a glass sealing layer and an electrode connecting column;

[0007] SOI silicon wafers are used to prepare silicon piezoresistive pressure sensitive chip wafers. The top silicon of the SOI silicon piezoresistive pressure sensitive chip is provided with a diffused silicon piezoresistive bridge resistor without a PN junction and a diffused silicon electrode and a peripheral frame connected to the outside of the bridge resistor, and the rest of the top silicon is removed. The silicon oxide insulating buried layer under the top silicon replaces the PN junction. When the temperature is as high as the ideal Young's modulus limit temperature of single crystal silicon, 556°C, the insulation isolation between the diffused bridge resistor and the electrode and the substrate silicon is still strong, and the silicon piezoresistive pressure sensitive function is normal. The diffused silicon electrode is provided with a multi-metal film electrode with overlapping centers and high temperature resistance, and its diameter is half the diameter of the diffused silicon electrode. An insulating gap is provided between the outer diameter of the diffused silicon electrode and the peripheral frame, and the width of the insulating gap is greater than the diameter of the diffused silicon electrode. Within a wide operating temperature range, the thermal stability of the ohmic connection between the chip's high temperature resistant multi-metal film electrode and the diffused silicon electrode and the electrode connecting column is long-term and reliable. On the substrate silicon, the inverted "mountain" shaped pressure measurement cavity and the "peak film" pressure sensing diaphragm are wet-etched in the center, which can directly measure the pressure of gas and liquid media compatible with single crystal silicon, without filling incompressible liquid to transmit the measured pressure. The length of the outer side of the bottom surface of the inverted "mountain" shaped pressure measurement cavity determines the side length of the "peak film" pressure sensing diaphragm.

[0008] A rectangular cavity is provided on the polished surface of the glass liner sealed with the SOI silicon piezoresistive pressure sensitive chip, the center of the rectangular cavity coincides with the center of the SOI silicon piezoresistive pressure sensitive chip, the side length of the rectangular cavity is greater than the side length of the "peak film" pressure-sensitive diaphragm, and the depth of the rectangular cavity is greater than the maximum deflection generated when the "peak film" pressure-sensitive diaphragm senses the upper limit pressure of the rated pressure range; four electrode plug holes are provided outside the rectangular cavity, the aperture is greater than the diameter of the multi-element metal film electrode, the hole center distribution coincides with the center distribution of the multi-element metal film electrode, and the minimum spacing between each side of the rectangular cavity and the edge of the electrode plug hole is greater than the diameter of the diffused silicon electrode. The polished surface outside the glass liner cavity is bonded to the silicon peripheral frame of the top layer of the chip and the annular electrode anode of the diffused silicon electrode greater than the outer diameter of the metal film electrode, forming a pressure reference cavity of the sensitive chip, isolating the chip diffused bridge resistance and the electrode from direct contact with the use environment. The setting of the three-dimensional scale of the cavity cannot limit the maximum deflection of the pressure-sensitive diaphragm when it senses the upper limit pressure of the rated pressure range, and a moderate three-dimensional scale can improve the pressure overload capacity of the chip. The soft point temperature of the glass liner is significantly higher than the highest process temperature of the fusion package. The thermal adaptation characteristics of the airtight seal with the silicon and glass sealing layer are stable and reliable for a long time within a wide operating temperature range.

[0009] The shell of the small-diameter cylindrical socket is made of high-temperature constant-elastic alloy, and there is no oxidation on the surface within a wide and wide operating temperature range. The inner column glass is made of hard insulating glass to reduce the weight of the socket, and the soft point temperature is much higher than the highest process temperature of the fusion package. The diameter of the inner glass column is equal to the diagonal dimension of the chip surface, and the diameter of the socket is minimized. The four variable-diameter metal electrode wires are made of high-temperature oxidation-resistant metal wires. The outer diameter of the thin end that passes through the inner glass column is the same as the outer diameter of the metal film electrode of the chip, and the center distribution of the metal electrode wire coincides with the center distribution of the metal film electrode of the chip. Within a wide and wide operating temperature range, the thermal adaptation characteristics of the airtight seal between the inner glass column and the alloy shell and the electrode wire are long-term strong and robust;

[0010] The glass sealing layer is formed by melting a prefabricated circular glass powder sheet, and the two sides form a solid sealing interface with the non-cavity surface of the glass liner of the sensitive chip and the surface of the glass inner column through which the thin end of the small-diameter tube base metal electrode plug wire passes, so that the sensitive chip is invertedly packaged on the glass inner column of the tube base; the soft point temperature of the glass powder is significantly higher than the ideal Young's modulus limit temperature of single crystal silicon, which is 556°C. Within a wide operating temperature range, the thermal adaptation characteristics of the glass sealing layer, the glass liner and the glass inner column are long-term stable and reliable;

[0011] The electrode connection column is formed by melting the conductive metal powder filled in the electrode socket, and is respectively alloyed with the surface of the chip's multi-element metal film electrode and the tube socket metal electrode wire thin end. No bonding wire is required, and the chip metal film electrode and the tube socket metal electrode wire thin end are ohmic connected, maximizing the chip packaging area efficiency. At the same time, the sensor has no movable components. The metal powder is selected from low-resistance metal powder, and the melting point temperature is significantly higher than the ideal Young's modulus limit temperature of single crystal silicon 556°C. Within a wide operating temperature range, the ohmic connection thermal characteristics of the electrode connection column and the metal film electrode and the tube socket metal electrode wire are long-term stable and reliable.

[0012] Before the prefabricated circular glass powder thin slice and the conductive powder material are synchronously melted, the prefabricated circular glass powder thin slice is stacked on the glass liner whose electrode plug hole is already filled with conductive powder material by using the alignment loading tool, and then the conductive metal powder material is dripped to fill the two layers of overlapping electrode plug holes. Then, the thin-diameter ends of the four high-temperature resistant variable-diameter metal electrode plug wires (3-2) of the tube holder are simultaneously aligned and inserted into the conductive metal powder material in the corresponding electrode plug holes, and the inverted sensitive chip is pre-installed on the glass inner column of the tube holder.

[0013] The prefabricated circular glass powder flakes and the conductive metal powder are synchronously vacuum-fused to form a glass sealing layer as a sealing medium. The sensitive chip is inverted, airtight, and solid-state encapsulated on the small-diameter tube holder glass inner column. The electrode connection column formed at the same time serves as an electrical connection medium, so that the chip metal electrode and the tube holder electrode wire thin-diameter end can achieve a robust ohmic connection. The soft point of the glass powder and the melting temperature of the conductive metal powder are significantly higher than 556℃.

[0014] Beneficial effects of the present invention:

[0015] 1) The electrical isolation of the diffused silicon piezoresistive bridge of the pressure-sensitive chip of the present invention adopts non-PN junction insulation isolation, and the upper limit of the applicable temperature of the chip multi-element metal film electrode ohmic contact, the softening point or melting point temperature of the functional material of the tube seat, the softening point temperature of the prefabricated glass sheet, and the melting point temperature of the conductive powder are significantly higher than the ideal limit temperature of the Young's modulus of single crystal silicon, which is 556°C. Within a wide temperature range below 556°C, the all-solid-state fused packaged silicon piezoresistive pressure sensor can stably, robustly, and reliably measure the high-temperature gas or liquid pressure compatible with single crystal silicon and inner column glass for a long time;

[0016] 2) After the top silicon surface of the sensitive chip is anodically bonded to the polished surface outside the glass substrate cavity and the electrode socket, the diffused silicon sensitive bridge is isolated in the pressure reference cavity formed by the glass substrate cavity and the pressure-sensitive diaphragm, replacing the conventional metal isolation liquid seal package to avoid the limitations of the filling liquid damping and thermal characteristics that lead to degradation of the sensor's dynamic and high-temperature environment adaptability.

[0017] 3) The prefabricated glass powder flakes and conductive powder are melted synchronously, so that the sensitive chip is inverted and sealed on the inner glass column of the tube holder, and the thin diameter end of the tube holder electrode wire connected to the chip metal ohm is embedded in the electrode connection column and cannot move. The sensor has no adhesive and no moving parts, is small and light, has a high natural frequency and a wide range, has the advantage of fast response to high-frequency pulsating gas or liquid pressure measurement, and is fully compatible with static or low-frequency pulsating gas or liquid pressure measurement;

[0018] 4) The high temperature oxidation resistant tube seat of the present invention has the characteristics of small diameter, light weight and high chip packaging area efficiency, which makes the sensor measurement installation diameter easy to probe, and has outstanding applicability advantages in high temperature and high frequency pulsating pressure in-situ measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a schematic top view of the top silicon surface of the high temperature resistant SOI silicon piezoresistive pulsating pressure sensitive chip of the present invention;

[0021] Figure 2 It is a schematic top view of the silicon surface of the high temperature resistant SOI silicon piezoresistive pulsating pressure sensitive chip substrate of the present invention;

[0022] Figure 3 The high temperature resistant SOI silicon piezoresistive pulsating pressure sensitive chip of the present invention is Figure 1 A vertical stereoscopic schematic diagram cut by a dotted line;

[0023] Figure 4 It is a schematic top view of the concave surface of the glass liner of the present invention;

[0024] Figure 5 The high temperature resistant SOI silicon piezoresistive pulsating pressure sensitive chip after bonding glass liner of the present invention is Figure 1 A vertical stereoscopic schematic diagram cut by a dotted line;

[0025] Figure 6 It is a longitudinal schematic cross-sectional view of the high temperature resistant silicon piezoresistive pulsating pressure sensor of the present invention;

[0026] Figure 7 It is a vertical stereoscopic schematic diagram of a high temperature resistant silicon piezoresistive pulsating pressure sensor of the present invention;

[0027] In the figure: 1. SOI silicon piezoresistive pressure sensitive chip; 1-1. Diffused silicon piezoresistive bridge resistor; 1-2. Diffused silicon electrode; 1-3. Multi-element metal film electrode; 1-4. Top silicon peripheral frame; 1-5. Inverted "mountain" shaped pressure measurement cavity; 1-6. "Peak film" pressure sensing diaphragm; 2. Glass lining; 2-1. Rectangular concave cavity; 2-2. Electrode socket; 3. Small-diameter tube socket; 3-1. Metal shell; 3-2. Electrode wire; 3-3. Glass inner column; 4. Glass sealing layer; 5. Electrode connecting column. DETAILED DESCRIPTION

[0028] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0029] As an embodiment of the present invention, Figure 1-Figure 7 As shown, a high temperature resistant silicon piezoresistive pulsating pressure sensor according to the present invention comprises a SOI silicon piezoresistive pressure sensitive chip 1, a glass liner 2, a small-diameter tube seat 3, a glass sealing layer 4 and an electrode connecting column 5;

[0030] The SOI silicon piezoresistive pressure sensitive chip 1 includes a diffused silicon piezoresistive bridge resistor 1-1 on the top silicon surface, a diffused silicon electrode 1-2, a multi-element metal film electrode 1-3, a rectangular peripheral frame 1-4, and an inverted "mountain" shaped pressure sensing cavity 1-5 and a "peak film" pressure sensing diaphragm 1-6 on the substrate silicon surface as a pressure measurement cavity. The single crystal silicon pressure measurement cavity can be in direct contact with the non-corrosive gas and liquid two-state pressure medium to be measured, avoiding the natural frequency and high temperature adaptability limitations of the filling and transmission of the measured pressure liquid;

[0031] A rectangular cavity 2-1 is arranged in the center of the polished surface of the glass substrate 2 and the sensitive chip 1, which is used as a pressure reference cavity. Four electrode plug holes 2-2 of the thin ends of the electrode plug wires 3-2 of the tube seat 3 are arranged outside the cavity, and the centers of the holes coincide with the centers of the multi-element metal film electrodes 1-3 one by one;

[0032] The small-diameter tube seat 3 is composed of a high-temperature oxidation-resistant alloy shell 3-1, four variable-diameter electrode wires 3-2 and a glass inner column 3-3. The glass inner column 3-3 is made of hard insulating glass, and its thermal adaptation characteristics with the alloy shell 3-1 and the electrode wire 3-2 are long-term stable and reliable, and its diameter is equal to the diagonal dimension of the chip 1. The electrode wire 3-2 is made of a high-temperature oxidation-resistant low-resistance metal wire, which runs through the glass inner column 3-3, and the diameter and center of the thin end hole coincide with the diameter and center of the multi-element metal film electrode 1-3 of the sensitive chip 1;

[0033] The glass sealing layer 4 is a sealing medium for the sensitive chip 1 to be invertedly packaged on the tube seat 3. It is formed by melting a prefabricated circular thin sheet of glass powder. The two sides form a solid sealing interface with the non-cavity surface of the glass liner 2 and the surface of the glass inner column 3-3 through which the thin end of the metal electrode plug wire 3-2 of the small-diameter tube seat 3 passes. The soft point temperature of the glass powder is significantly higher than the ideal Young's modulus limit temperature of single crystal silicon, which is 556°C. Within a wide operating temperature range, the thermal adaptation characteristics of the glass sealing layer 4, the glass liner 2 and the glass inner column 3-3 are airtightly sealed and stable for a long time.

[0034] The electrode connection column 5 is formed by melting the conductive metal powder buried in the electrode plug hole of the glass liner 2 and prefabricated circular thin slices of glass powder. The alloy is melted on the surface of the multi-element metal film electrode 1-3 of the chip 1 and the thin end of the electrode plug wire 3-2 of the tube seat 1 without bonding the movable metal wire. The chip metal film electrode 1-3 and the thin end of the electrode plug wire 3-2 of the tube seat 1 are connected in an ohmic manner. While maximizing the chip packaging area efficiency, the thin end of the electrode plug wire 3-2 is embedded in the electrode connection column 5, and the sensor has no movable components. The metal powder is selected from low-resistance metal powder, and the melting point temperature is significantly higher than the ideal Young's modulus limit temperature of single crystal silicon 556°C. In a wide operating temperature range, the ohmic connection thermal characteristics of the electrode connection column 5, the multi-element metal film electrode 1-3 and the thin diameter end of the tube seat metal electrode plug wire 3-2 are long-term stable and reliable.

[0035] The premise of the robustness and robustness of the inverted package of the sensitive chip 1 and the small-diameter tube seat 3 depends on the accuracy of the sensitive chip 1 being inverted and mounted on the glass inner column through which the thin-diameter end of the metal electrode plug wire 3-2 of the small-diameter tube seat 3 passes. Using the alignment loading tool, after the prefabricated circular glass powder sheet is stacked on the glass liner whose electrode plug hole is filled with conductive powder, the conductive metal powder is dripped to fill the two overlapping upper and lower electrode plug holes, and then the thin-diameter ends of the four high-temperature resistant variable-diameter metal electrode plug wires 3-2 of the tube seat are simultaneously aligned and inserted into the conductive metal powder in the corresponding upper and lower electrode plug holes.

[0036] A method for manufacturing a high temperature resistant silicon piezoresistive pulsating pressure sensor comprises the following steps:

[0037] S1. In the top silicon layer of the SOI wafer, a sensitive chip is fabricated by silicon planar technology. The diffusion silicon piezoresistive pressure-sensitive closed bridge has no PN junction, small zero-point dispersion, high linearity, large sensitivity, and thermal drift mutual cancellation. A peripheral frame of the top silicon is sealed to the glass substrate.

[0038] S2. On the diffusion silicon electrodes where the sensitive chip is electrically connected to the outside, a high-temperature-resistant multi-metal film electrode with robust ohmic contact characteristics and thermal stress matching is fabricated by thin-film technology.

[0039] S3. A reverse "mountain"-shaped pressure measurement cavity is wet-etched on the substrate silicon. Double-sided lithography enables high-precision vertical alignment of the center of the peripheral sealing frame plane of the top silicon and the center of the pressure measurement cavity plane.

[0040] S4. Through wafer-level anodic bonding, the peripheral frame of the chip top silicon and the exposed annular part of the diffusion silicon electrodes are hermetically and rigidly sealed to the polished surface outside the concave cavity and through holes of the glass substrate.

[0041] S5. After dropwise adding conductive powder materials and precisely and uniformly filling the four electrode jacks of the glass substrate, a prefabricated circular glass powder thin sheet is laminated on the glass substrate using a collimating mounting tooling. The centers of the four electrode jacks of the two layers with the same diameter overlap vertically. Then, conductive powder materials are dropwise added and precisely and uniformly filled into the laminated electrode jacks of the glass powder thin sheet.

[0042] S6. Using the collimating mounting tooling, the sensitive chip is inverted and laminated on the inner column of the socket glass. The thin ends of four high-temperature-resistant stepped metal electrode wires are simultaneously and collimatedly inserted into the conductive powder materials in the corresponding four electrode jacks.

[0043] S7. Synchronous vacuum melting and solidification of the prefabricated circular glass powder thin sheet and the conductive metal powder materials. The formed glass sealing layer serves as a sealing medium, and the sensitive chip is inverted, hermetically, and solidly encapsulated on the inner column of the small-diameter socket glass. At the same time, the formed electrode connection columns serve as electrical connection media, enabling a robust ohmic connection between the chip metal electrodes and the thin ends of the socket electrode wires.

[0044] The above has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of protection required by the present invention. The scope of protection required by the present invention is defined by the appended claims and their equivalents.

Claims

1. A high temperature resistant silicon piezoresistive pulsation pressure sensor, characterized in that: It comprises an SOI silicon piezoresistive pressure sensitive chip (1), a glass liner (2), a small-diameter tube seat (3), a glass sealing layer (4) and an electrode connecting column (5); The top silicon of the SOI silicon piezoresistive pressure sensitive chip (1) is provided with a diffused silicon piezoresistive bridge resistor (1-1) without a PN junction and a diffused silicon electrode (1-2) and a peripheral frame (1-4) connected to the bridge resistor and the outside; the diffused silicon electrode (1-2) is provided with a multi-element metal film electrode (1-3) with overlapping centers, and the multi-element metal film electrode (1-3) is a high temperature resistant electrode, and its diameter is half the diameter of the diffused silicon electrode (1-2); an insulating spacer is provided between the outer diameter of the diffused silicon electrode (1-2) and the peripheral frame (1-4), and the width of the insulating spacer is greater than the diameter of the diffused silicon electrode (1-2); an inverted "mountain" shaped pressure measurement cavity (1-5) and a "peak film" pressure sensing diaphragm (1-6) are centrally provided on the substrate silicon, and the outer side length of the root cut of the bottom surface of the inverted "mountain" shaped pressure measurement cavity (1-5) determines the side length of the "peak film" pressure sensing diaphragm (1-6).

2. The high temperature resistant silicon piezoresistive pulsation pressure sensor according to claim 1, characterized in that: The glass liner (2) is double-sided polished, and a rectangular cavity (2-1) is provided on the polished surface sealed with the SOI silicon piezoresistive pressure sensitive chip (1), the center of the rectangular cavity (2-1) coincides with the center of the SOI silicon piezoresistive pressure sensitive chip (1) in upper and lower directions, the side length of the rectangular cavity (2-1) is greater than the side length of the "peak film" pressure-sensitive diaphragm (1-6), and the depth of the rectangular cavity (2-1) is greater than the maximum deflection generated when the "peak film" pressure-sensitive diaphragm (1-6) senses the upper limit pressure of the rated pressure range; four electrode plug holes (2-2) are provided outside the rectangular cavity (2-1), the hole diameter is greater than the diameter of the multi-element metal film electrode (1-3), the hole center distribution coincides with the circle center distribution of the multi-element metal film electrode (1-3) in upper and lower directions, and the minimum spacing between each side of the rectangular cavity (2-1) and the edge of the electrode plug hole (2-2) is greater than the diameter of the diffused silicon electrode (1-2).

3. The high temperature resistant silicon piezoresistive pulsation pressure sensor according to claim 1, characterized in that: The small-diameter tube seat (3) comprises an alloy shell (3-1), four variable-diameter metal electrode plug wires (3-2) and an insulating glass inner column (3-3); the alloy shell (3-1) is made of a high-temperature constant-elastic alloy, and its inner diameter is larger than the plane diagonal dimension of the SOI silicon piezoresistive pressure sensitive chip (1); the four variable-diameter metal electrode plug wires (3-2) are made of high-temperature oxidation-resistant metal wires, which penetrate the glass inner column (3-3), and the diameter and center distribution of the thin ends of the metal electrode plug wires (3-2) coincide with the diameter and center distribution of the multi-element metal film electrode (1-3); the glass inner column (3-3) is made of hard insulating glass, and its thermal adaptation characteristics with the alloy shell (3-1) and the metal electrode plug wire (3-2) are stable and reliable.

4. The high temperature resistant silicon piezoresistive pulsation pressure sensor according to claim 1, characterized in that: The glass sealing layer (4) is formed by melting a prefabricated circular thin sheet of glass powder, and its two sides form a sealing interface with the non-cavity surface of the glass liner (2) and the surface of the glass inner column (3-3) of the small-diameter tube seat (3), respectively, and is used as a sealing medium for the SOI silicon piezoresistive pressure sensitive chip (1) to be invertedly packaged on the small-diameter tube seat (3); the thermal properties of the glass powder material selection match the thermal properties of the glass liner (2) and the glass inner column (3-3) of the small-diameter tube seat (3); the diameter of the glass sealing layer (4) is the same as the inner diameter of the alloy shell (3-1), and four electrode plug holes are provided on the glass sealing layer (4), and the hole diameter and circle center distribution are overlapped with the hole diameter and circle center distribution of the four electrode plug holes (2-2) of the glass liner (2).

5. The high temperature resistant silicon piezoresistive pulsation pressure sensor according to claim 1, characterized in that: The electrode connection column (5) is formed by melting the conductive powder material of the electrode plug hole filled with the glass liner (2) and the prefabricated circular glass powder thin sheets stacked up and down. The alloy interface between the electrode connection column (5) and the surface of the thin end of the multi-element metal film electrode (1-3) of the SOI silicon piezoresistive pressure sensitive chip (1) and the small-diameter tube seat (3) metal electrode plug wire (3-2) becomes a conductive medium for electrically connecting the high-temperature resistant multi-element metal film electrode (1-3) and the thin end of the metal electrode plug wire (3-2); the low-resistance conductive metal powder is selected, and the ohmic connection thermal characteristics with the metal film electrode (1-3) and the thin end of the metal electrode plug wire (3-2) are stable and reliable.

6. The high temperature resistant silicon piezoresistive pulsation pressure sensor according to claim 1, characterized in that: The exposed annular portion of the top silicon peripheral frame (1-4) and the diffused silicon electrode (1-4) of the SOI silicon piezoresistive pressure sensitive chip (1) is hermetically sealed with the polished surface outside the rectangular cavity (2-1) and the electrode plug hole (2-2) of the glass substrate (2) to serve as the pressure reference cavity of the SOI silicon piezoresistive pressure sensitive chip (1), and the multi-element metal film electrode (1-3) is exposed in the electrode plug hole (2-2) corresponding to the glass substrate (2).

7. The high temperature resistant silicon piezoresistive pulsation pressure sensor according to claim 1, characterized in that: The prefabricated circular glass powder thin slice and the low-resistance conductive metal powder are synchronously vacuum-fused to simultaneously realize the inverted sealing of the SOI silicon piezoresistive pressure sensitive chip (1) and the small-diameter tube seat (3) and the ohmic electrical connection between the multi-element metal film electrode (1-3) and the thin end of the high-temperature resistant electrode plug wire (3-2); before the synchronous vacuum-fused, the prefabricated circular glass powder thin slice is aligned and stacked on the non-cavity polished surface of the glass liner (2), and after the low-resistance conductive metal powder fills the stacked electrode plug hole, the end face of the glass inner column (3-3) through which the thin-diameter end of the high-temperature oxidation-resistant metal electrode plug wire (3-2) passes is inverted on the prefabricated circular glass powder thin slice, and the thin-diameter ends of four high-temperature resistant metal electrode plug wires (3-2) are simultaneously and respectively aligned and inserted into the low-resistance conductive metal powder filled in the stacked electrode plug hole.

8. A method for manufacturing a high temperature resistant silicon piezoresistive pulsation pressure sensor according to any one of claims 1 to 7, characterized in that: The steps include: S1. In the top silicon of SOI silicon wafer, a sensitive chip is prepared by silicon planar process, which has no PN junction, small zero point discreteness, high linearity, high sensitivity, and thermal drift offset, and a diffused silicon piezoresistive pressure sensitive closed bridge and a top silicon peripheral frame sealed with a glass liner; S2. On the diffused silicon electrode electrically connected to the sensitive chip and the outside, a high-temperature resistant multi-metal film electrode with robust ohmic contact characteristics and thermal stress matching is prepared by thin film technology; S3. Wet-etch a reverse "mountain"-shaped pressure measurement cavity on the substrate silicon, and use double-sided lithography to make the centers of the top silicon peripheral sealing frame plane and the pressure measurement cavity plane overlap precisely vertically with high precision; S4. Through wafer-level anodic bonding, make the peripheral frame of the top silicon of the chip and the exposed annular part of the diffused silicon electrode be hermetically and rigidly sealed with the polished surface outside the concave cavity and through holes of the glass substrate; S5. Drop conductive powder materials, precisely and evenly fill the four electrode jacks of the glass substrate, and then use a collimating chip-loading tooling to stack a prefabricated circular glass powder thin sheet on the glass substrate. The centers of the four electrode jacks with the same diameter of the two layers overlap vertically. Drop conductive powder materials and precisely and evenly fill the electrode jacks of the stacked glass powder thin sheet layer; S6. Use the collimating chip-loading tooling to pre-invert the sensitive chip on the inner column of the socket glass, and simultaneously insert the thin-diameter ends of the four stepped metal electrode wires straight into the conductive powder materials in the four corresponding electrode jacks; S7. Through the synchronous vacuum melting and solidification of the prefabricated circular glass powder thin sheet and the conductive metal powder materials, with the glass sealing layer as the sealing medium, the sensitive chip is inverted, hermetically and solidly packaged on the inner column of the small-diameter socket glass. The electrode connection column simultaneously serves as the electrical connection medium, enabling a robust ohmic connection between the chip metal electrode and the thin-diameter end of the socket electrode wire.

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