High temperature resistant micro-acoustic sensing chip package structure

Abstract

This invention provides a high-temperature resistant micro-acoustic sensing chip packaging structure, including a micro-acoustic chip, a cap, a base, and P-type pins. The base is securely connected to the cap and forms a sealed receiving space inside. The micro-acoustic chip is securely mounted inside the base, and a bus electrode plate is provided on the micro-acoustic chip. The base has multiple through holes for mounting the P-type pins. The upper end of the P-type pin passes through the through holes and is connected to the micro-acoustic chip via conductive metal paste, while the lower end of the P-type pin extends to the bottom of the base. This invention uses exposed electrodes, with the micro-acoustic chip fixed in a recess in the base, and the electrodes are electrically connected to the through-hole pins, enabling stable electrical signal transmission at high temperatures. The through-hole pins are bonded to the base with ceramic paste, and the cap is bonded to the base via pressure welding. This provides high resistance to thermal fatigue and corrosion, effectively reducing peeling and cracking during use and extending the package's lifespan.

Description

Technical Field

[0001] This invention relates to the field of low-temperature acoustic sensing chip packaging structure technology, specifically, to a high-temperature resistant low-temperature acoustic sensing chip packaging structure. Background Technology

[0002] With the development of the manufacturing industry, sensor technology is increasingly being applied in manufacturing. Sensors can convert chemical, physical, and electrical quantities into digital signals that computers can recognize, reflecting various parameters in real time. The operational safety of intelligent manufacturing is closely related to environmental factors. When the operating environment is harsh, it can have a significant negative impact on the overall efficiency of intelligent manufacturing operations, and in severe cases, can lead to numerous malfunctions. The flexible application of sensor technology in intelligent manufacturing can effectively analyze the basic operating status of the system, transmit various data information to system schedulers, and enable standardized control of intelligent manufacturing operations.

[0003] Many systems in smart manufacturing operate in harsh environments, and a growing trend is for sensing elements to be placed closer to high-temperature areas. This trend is driven by several factors, manifesting in energy exploration, aerospace, automotive, steel metallurgy, and other end-use applications. For example, in the steel metallurgy sector, equipment typically operates above 300°C, with short-term operating temperatures reaching 600°C. Due to the harsh installation environment and high-temperature limitations, active sensing devices are difficult to implement practically. Sensing elements that meet application requirements need to be placed close to high-temperature equipment, such as ladle surface temperature detection and ladle number identification. Historically, it has been very difficult for engineers to design reliable, high-performance sensing elements for these applications because there is a lack of manufacturers producing components specifically for these operating conditions. Fortunately, in recent years, an increasing number of wireless passive devices have emerged, with continuously improving temperature resistance. For example, the micro-acoustic chips in micro-acoustic tags used in the steel metallurgy industry employ piezoelectric materials and contain no electronic components, thus offering a lifespan far exceeding that of RFID tags, making them ideal for applications requiring year-round maintenance-free operation. The substrate material and electrodes used in the micro-acoustic marker can operate normally at a high temperature of 600℃. When used with a high-temperature resistant antenna, it can work for a long time in a high-temperature environment of 600℃-650℃ on the surface of high-temperature equipment.

[0004] It is worth noting that the application of wireless passive sensing elements in high-temperature environments relies heavily on high-temperature resistant packaging structures. Patent application CN113739950A, entitled "A Surface Acoustic Wave Temperature Sensor, High-Temperature Resistant Packaging Structure and Packaging Method," provides a packaging structure including a ceramic packaging cover, a transition material layer, an insulating layer, and a ceramic packaging base. This solution focuses on the stacking and combination of high-temperature resistant materials for the temperature sensing chip, such as using embedded electrodes and aluminum nitride protective layers, but lacks specific high-temperature resistant design in the packaging structure. Patent application CN114132885A, entitled "A Leadless Packaging Structure and Method for a High-Temperature Resistant Sensor," provides a leadless packaging structure including a sensor chip, a sensor housing, and metal pins. This solution simplifies the packaging lead method, but the structural design is complex, and different components are affected differently by structural thermal stress in high-temperature environments, posing challenges for high-temperature use.

[0005] Therefore, there is a need for a high-temperature resistant micro-acoustic sensing chip packaging structure that is simple and reliable, easy to install, has a high yield, and low manufacturing cost. It can not only maintain structural stability and normal operation at high temperatures, but also has high resistance to thermal fatigue and corrosion, which can meet the needs of use in harsh environments and effectively extend the service life of the packaging. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the purpose of this invention is to provide a high-temperature resistant micro-acoustic sensing chip packaging structure.

[0007] According to the present invention, a high-temperature resistant micro-acoustic sensing chip packaging structure includes: a micro-acoustic chip, a cover, a base, and P-type pins. The base is fastened to the cover and forms a sealed receiving space inside. The micro-acoustic chip is fastened inside the base, and a bus electrode plate is disposed on the micro-acoustic chip.

[0008] The base is provided with multiple through holes for mounting the P-type pins. The upper end of the P-type pins passes through the through holes and is connected to the micro-acoustic chip through conductive metal paste. The lower end of the P-type pins extends to the bottom of the base.

[0009] Preferably, the base includes an upper base and a lower base, and the microacoustic chip is installed in a base groove at the center of the upper base.

[0010] Preferably, the center of the microacoustic wafer coincides with the center of the base groove, and there is a gap between the edge of the microacoustic wafer and the groove wall of the base groove.

[0011] Preferably, the microacoustic chip is bonded to the base groove by an adhesive, the adhesive comprising a heat-curing inorganic adhesive.

[0012] Preferably, multiple through holes are symmetrically arranged on both sides of the base groove, and each through hole corresponds to a P-type pin. The sidewall of the P-type pin is bonded to the hole wall of the through hole by curing ceramic slurry.

[0013] Preferably, four through holes are symmetrically arranged on both sides of the base groove, and the two P-type pins near the busbar electrode plate are electrically connected to the busbar electrode plate.

[0014] Preferably, the lower base has a tapered protrusion along its edge, and the base and the cover are fastened together by a pressure welding process, with the outer surfaces of the base and the cover smoothly connected.

[0015] Preferably, the microacoustic wafer includes a substrate made of lithium niobate, and the busbar electrode plate is disposed on the upper surface of the substrate, the busbar electrode plate being made of platinum or tungsten.

[0016] Preferably, the conductive metal paste includes electrode platinum paste.

[0017] Preferably, the base is made of Kovar alloy, and the P-type pin is made of Kovar alloy.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] This invention uses a micro-acoustic chip fixed in a groove in the base, employing exposed electrodes. The electrodes are electrically connected to the through-hole pins, enabling stable electrical signal transmission at high temperatures. The through-hole pins are bonded to the base with ceramic paste, and the cap is bonded to the base by pressure welding. This provides high resistance to thermal fatigue and corrosion, effectively reducing peeling and cracking during use and extending the package's lifespan. The structure is simple and reliable, easy to install, and has significant advantages in yield and manufacturing cost compared to similar products. It maintains structural stability and normal operation at high temperatures, meeting the needs of use in harsh environments. Attached Figure Description

[0020] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0021] Figure 1 This is an exploded view of the packaging structure of the high-temperature resistant micro-acoustic sensing chip, which is the main feature of this invention.

[0022] Figure 2 This is a schematic diagram of the overall structure of the high-temperature resistant micro-acoustic sensing chip packaging structure of the present invention.

[0023] Figure 3 This is a schematic diagram illustrating the structure of the base, which is the main feature of this invention.

[0024] Figure 4 This is a schematic diagram illustrating the structure of the micro-acoustic wafer, which is the main feature of this invention.

[0025] As shown in the figure:

[0026] Microchip 1, Cover 2, Base 3

[0027] P-pin 4, Ceramic paste 5, Busbar electrode plate 101

[0028] Base 102, Upper base 301, Lower base 302

[0029] Base groove 303, through hole 304, conical protrusion 306 Detailed Implementation

[0030] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0031] like Figure 1-4 As shown, a high-temperature resistant micro-acoustic sensing chip packaging structure provided by the present invention includes: a micro-acoustic chip 1, a cover 2, a base 3, and P-type pins 4. The base 3 is tightly connected to the cover 2 and forms a sealed receiving space inside. The micro-acoustic chip 1 is tightly installed inside the base 3, and a bus electrode plate 101 is provided on the micro-acoustic chip 1. The base 3 is provided with a plurality of through holes 304 for mounting the P-type pins 4. The upper end of the P-type pin 4 passes through the through hole 304 and is electrically connected to the micro-acoustic chip 1 through conductive metal paste. The lower end of the P-type pin 4 extends to the bottom of the base 3.

[0032] The micro-acoustic sensing chip packaging structure of this application for high temperature resistance specifically refers to a micro-acoustic sensing chip used in high temperature environments. The structure of this application is simple and reliable, and can maintain the stability of the structure and work normally at a high temperature of 600℃, which can meet the needs of use in harsh environments.

[0033] The base 3 includes an upper base 301 and a lower base 302. The micro-acoustic chip 1 is installed in the base groove 303 at the center of the upper base 301. The center of the micro-acoustic chip 1 coincides with the center of the base groove 303, and there is a gap between the edge of the micro-acoustic chip 1 and the groove wall of the base groove 303.

[0034] The microacoustic chip 1 includes a substrate 102 made of lithium niobate. A busbar electrode plate 101 is disposed on the upper surface of the substrate 102, and the busbar electrode plate 101 is made of platinum or tungsten. The microacoustic chip 1 is bonded to the base groove 303 by a high-temperature adhesive, which includes a heat-curing inorganic adhesive.

[0035] Multiple through holes 304 are symmetrically arranged on both sides of the base groove 303. Each through hole 304 corresponds to a P-type pin 4. The sidewall of the P-type pin 4 is bonded to the hole wall of the through hole 304 by a ceramic slurry 5. In other words, the P-type pin 4 passes through the through hole 304 and is cast to the base 3 using the ceramic slurry 5. The base 3 is made of Kovar alloy, and the P-type pin 4 is also made of Kovar alloy.

[0036] Preferably, four through holes 304 are symmetrically arranged on both sides of the base groove 303. Two P-type pins 4 near the busbar plate 101 are electrically connected and fixed to the busbar plate 101, and the other P-type pins 4 are used for chip fixing. In other specific embodiments, the number of P-type pins 4 can be adjusted according to the actual situation.

[0037] The bus electrode plate 101 is connected to the P-type pin 4 via a conductive metal paste, enabling stable electrical signal transmission at high temperatures. The conductive metal paste comprises a low-resistivity electrode platinum paste with a dense film layer.

[0038] The lower base 302 has a tapered protrusion 306 on its edge. The base 3 and the cover 2 are fastened together by resistance welding. The outer surfaces of the base 3 and the cover 2 are smoothly connected.

[0039] The microacoustic chip 1 of this application is fixed within the recess 303 of the base and employs exposed electrodes. The electrodes are electrically connected to the through-hole pins, enabling stable electrical signal transmission at high temperatures. The through-hole pins are bonded to the base 3 using ceramic paste 5, and the cover 2 is bonded to the base 3 by pressure welding. This provides high resistance to thermal fatigue and corrosion, effectively reducing peeling and cracking during use and extending the package's lifespan. This application features a simple and reliable structure, convenient installation, and significant advantages in yield and manufacturing cost compared to similar products. It maintains structural stability and normal operation at 600℃, meeting the requirements for use in harsh environments.

[0040] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0041] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A high-temperature resistant micro-acoustic sensing chip packaging structure, characterized in that, include: Microacoustic chip (1), cover (2), base (3) and P-type pin (4), the base (3) is fastened to the cover (2) and forms a sealed receiving space inside, the microacoustic chip (1) is fastened inside the base (3), and a bus electrode plate (101) is provided on the microacoustic chip (1); The base (3) is provided with a plurality of through holes (304) for mounting the P-type pin (4). The upper end of the P-type pin (4) passes through the through hole (304) and is connected to the micro-acoustic chip (1) by conductive metal paste. The lower end of the P-type pin (4) extends to the bottom of the base (3).

2. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 1, characterized in that, The base (3) includes an upper base (301) and a lower base (302), and the micro-acoustic chip (1) is installed in the base groove (303) at the center of the upper base (301).

3. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 2, characterized in that, The center of the micro-acoustic chip (1) coincides with the center of the base groove (303), and there is a gap between the edge of the micro-acoustic chip (1) and the groove wall of the base groove (303).

4. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 2, characterized in that, The micro-acoustic chip (1) is bonded to the base groove (303) by an adhesive, the adhesive including a heat-curing inorganic adhesive.

5. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 2, characterized in that, The base groove (303) has multiple through holes (304) symmetrically arranged on both sides. The through holes (304) correspond one-to-one with the P-type pins (4). The sidewalls of the P-type pins (4) and the hole walls of the through holes (304) are bonded together by ceramic slurry (5) through curing.

6. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 5, characterized in that, Four through holes (304) are symmetrically arranged on both sides of the base groove (303), and the two P-type pins (4) near the busbar electrode plate (101) are electrically connected to the busbar electrode plate (101).

7. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 2, characterized in that, The lower base (302) has a tapered protrusion (306) on its edge. The base (3) and the cover (2) are fastened together by pressure welding. The outer surfaces of the base (3) and the cover (2) are smoothly connected.

8. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 1, characterized in that, The microacoustic wafer (1) includes a substrate (102) made of lithium niobate, and a busbar electrode plate (101) disposed on the upper surface of the substrate (102) made of platinum or tungsten.

9. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 1, characterized in that, The conductive metal paste includes electrode platinum paste.

10. The high-temperature resistant micro-acoustic sensing chip packaging structure as described in claim 1, characterized in that, The base (3) is made of Kovar alloy, and the P-type pin (4) is made of Kovar alloy.

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