Vibration sensor packaging structure

Abstract

A vibration sensor packaging structure is disclosed, comprising: a substrate, in which a first air hole penetrating the substrate is formed; a packaging shell, which is fixed to the surface of the substrate and forms a first cavity with the substrate; a MEMS chip, which is fixed to the surface of the substrate and located in the first cavity, and the MEMS chip has a second cavity, which is connected to the first air hole; wherein the side wall of the first air hole and / or the second cavity is also formed with a second air hole, which connects the first cavity with the first air hole and / or the second cavity. The vibration sensor packaging structure of the present application reduces the noise interference caused by the sound signal in the air to the vibration sensor by forming the second air hole connecting the first air hole and the first cavity in the side wall of the first air hole and / or the second cavity, thereby improving the yield and reliability of the device.

Description

Technical Field

[0001] The present invention relates to the technical field of MEMS devices, and in particular to a vibration sensor packaging structure. Background Art

[0002] Vibration is widely present in nature, industry and human life, and different vibrations transmit various signals. To obtain the information carried in vibration, we need to use various vibration sensors, which are widely used in many fields such as energy, chemical industry, medicine, automobile, metallurgy, machinery manufacturing, military industry, scientific research and teaching. For example, the sound signal transmitted by air vibration is read through a microphone; the accelerometer is used to measure the acceleration of the vibrating object; the ultrasonic detector detects and analyzes the vibration signal of mechanical equipment to determine the degree of deterioration of the machine itself and predict its life; the geological disaster early warning device detects the geological vibration caused by seismic waves to warn of earthquakes and other disasters.

[0003] Common sensors in the market include microphone sensors, pressure sensors, and acceleration sensors. Microphone sensors have been extended to bone conduction microphones that convert sound signals through vibration. Traditional bone conduction microphones transmit compressed air to the MEMS diaphragm through the vibration of the mass block. However, the existing vibration microphones are easily affected by the sound signals transmitted in the air, resulting in large noise in the received signals, thereby reducing the yield and reliability of the vibration sensor. Summary of the invention

[0004] In view of the above problems, the object of the present invention is to provide a vibration sensor packaging structure, which reduces the influence of the sound signal on the vibration signal in the signal received by the sensor by changing the air flow path in the vibration sensor, thereby improving the yield and reliability of the vibration sensor.

[0005] According to one aspect of the present invention, there is provided a vibration sensor packaging structure, comprising: a substrate, in which a first air hole is formed that passes through the substrate; a packaging shell, which is fixed to the surface of the substrate and forms a first cavity between the packaging shell and the substrate; a MEMS chip, which is fixed to the surface of the substrate and is located in the first cavity, and the MEMS has a second cavity, which is connected to the first air hole; wherein the side walls of the first air hole and / or the second cavity are further formed with a second air hole, and the second air hole connects the first cavity with the first air hole and / or the second cavity.

[0006] Optionally, the MEMS chip comprises a supporting structure, and one bottom portion of the supporting structure is fixed on the surface of the substrate by colloid.

[0007] Optionally, at least one groove is formed on the surface of the substrate, and at least one second air hole is formed between the groove and a portion of the bottom of the support structure, and the second air hole is located below one and / or multiple side surfaces of the support structure.

[0008] Optionally, at least one notch penetrating through the bottom of the support structure is formed in the support structure, and a second air hole is formed between the notch and a portion of the surface of the substrate.

[0009] Optionally, the notch is located below one and / or more sides of the support structure.

[0010] Optionally, at least one through hole is further provided on the MEMS chip, and the peripheral side of the through hole is surrounded by the supporting structure to form a second air hole.

[0011] Optionally, at least one through hole is further provided on the MEMS chip, and the peripheral side of the through hole is surrounded by the supporting structure to form a second air hole.

[0012] Optionally, the MEMS chip further includes a diaphragm and a back plate, and the positions of the diaphragm and the back plate are interchangeable.

[0013] Optionally, a cross-sectional shape of the second air hole along the side wall surface of the first air hole and / or the second cavity includes a square, a circle, and a polygon.

[0014] Optionally, the cross-sectional shape of the groove along the direction perpendicular to the first surface of the substrate is any one of square, circle or polygon.

[0015] Optionally, it further includes: an ASIC chip, and the MEMS chip is electrically connected to the ASIC chip.

[0016] Optionally, the second surface of the substrate includes a first solder pad and a second solder pad.

[0017] The vibration sensor packaging structure provided by the present invention forms a second air hole in the side wall of the first air hole and / or the second cavity, and the second air hole connects the first air hole and the first cavity, so that the first air hole is not only connected to the second cavity of the sensor, but also connected to the first cavity through the second air hole, so that the surface of the diaphragm in the MEMS chip facing the first cavity can also receive air and pressure, reducing the noise interference brought to the vibration sensor by the sound signal when only the second cavity of the MEMS chip receives air and pressure, thereby improving the yield and reliability of the vibration sensor.

[0018] The vibration sensor packaging structure provided by the present invention forms a second air hole in the side wall of the first air hole and / or the second cavity, and the second air hole connects the first air hole and the first cavity, so that when the sound signal reaches the surface of the diaphragm in the MEMS chip facing the first cavity along the first air hole and the second air hole, the time difference with the time taken for the sound signal to reach the surface of the diaphragm in the MEMS chip facing the second cavity along the first air hole is small, and the sound signals are the same, thereby being able to minimize the noise interference of the sound signal on the vibration sensor.

[0019] The vibration sensor packaging structure of the present application forms a variety of second air holes in the side walls of the first air hole and / or the second cavity to connect the first cavity and the second cavity, including a groove located in the surface of the substrate, a notch located in the MEMS chip and penetrating the bottom of the supporting structure, and a through hole penetrating the supporting structure. When the groove or the notch makes the connection between the first cavity and the second cavity not smooth due to other reasons, the through hole ensures that the sound signal can be transmitted to the upper and lower sides of the diaphragm, thereby reducing interference and improving the reliability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0021] Figure 1 A structural diagram showing a vibration sensor packaging structure according to a first embodiment of the present invention;

[0022] Figure 2a and Figure 2b A schematic diagram of a first surface of a substrate in a vibration sensor packaging structure according to a first embodiment of the present invention is shown;

[0023] Figure 3 A schematic diagram showing a second surface of the substrate in the vibration sensor packaging structure of the first embodiment of the present invention is shown;

[0024] Figure 4 A structural diagram showing a vibration sensor packaging structure according to a second embodiment of the present invention;

[0025] Figure 5 A structural diagram showing a vibration sensor packaging structure according to a third embodiment of the present invention;

[0026] Figure 6a A three-dimensional schematic diagram showing a MEMS chip in a vibration sensor packaging structure of the second embodiment and the third embodiment of the present invention

[0027] Figure 6b A three-dimensional schematic diagram of a MEMS chip in a vibration sensor packaging structure according to a fourth embodiment of the present invention is shown;

[0028] Figure 6cA three-dimensional schematic diagram of a MEMS chip in a vibration sensor packaging structure according to a fifth embodiment of the present invention is shown. DETAILED DESCRIPTION

[0029] The present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, the same elements are represented by similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale. In addition, some well-known parts may not be shown. For the sake of simplicity, the semiconductor structure obtained after several steps can be described in one figure.

[0030] It should be understood that when describing the structure of a device, when a layer or a region is referred to as being "on" or "over" another layer or another region, it may mean that it is directly on the other layer or another region, or that other layers or regions are included between it and the other layer or another region. Furthermore, if the device is turned over, the layer or a region will be "below" or "beneath" another layer or another region.

[0031] If it is intended to describe a situation where it is directly on another layer or another area, this article will use the expression “directly on…” or “on… and adjacent to…”.

[0032] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0033] Figure 1 A structural diagram showing a vibration sensor packaging structure according to a first embodiment of the present invention; Figure 2a and Figure 2b A schematic diagram of a first surface of a substrate in a vibration sensor packaging structure according to a first embodiment of the present invention is shown; Figure 3 A schematic diagram of the second surface of the substrate in the vibration sensor packaging structure of the first embodiment of the present invention is shown.

[0034] refer to Figure 1The vibration sensor packaging structure 100 of the first embodiment of the present invention includes: a substrate 3, a first air hole 5 penetrating the substrate 3 is formed in the substrate 3, a groove 41 is formed on the first surface of the substrate 3, and the groove 41 is connected to the first air hole 5; a packaging shell 1, the packaging shell 1 is fixed to the first surface of the substrate 3, and a first cavity 2 is formed between the packaging shell 1 and the substrate 3, and the groove 41 and the first air hole 5 are located in the first cavity 2; a MEMS chip 10 is arranged in the first cavity 2, the MEMS chip 10 includes a diaphragm 11, a back plate 12 and a supporting structure, the top of the supporting structure supports the diaphragm 11 and the back plate 12, and the bottom is fixed to the first surface of the substrate 3, the groove 41 and part of the bottom form a second air hole, a second cavity 6 is formed between the diaphragm 11 and the substrate 3, and the second cavity 6 is located above the first air hole 5, so that the second cavity 6 is connected to the outside through the first air hole 5, and the second cavity 6 is also connected to the first cavity 2 through the first air hole 5 and the second air hole.

[0035] The vibration sensor package structure 100 further includes an ASIC chip 13, which is disposed on the first surface of the substrate 3 in the first cavity 2. The ASIC chip 13 is a dedicated integrated circuit chip, which is connected to the MEMS chip 10 through a wire 14. In this specific embodiment, the dedicated integrated circuit chip 13 is fixed to the first surface of the substrate 3. In other specific embodiments, the dedicated integrated circuit chip 13 can also be embedded or integrated inside the substrate 3. The dedicated integrated circuit chip 13 is used to obtain the sensing signal output by the MEMS chip 10 and process it.

[0036] The material of the substrate 3 can be RF-4, BT or ceramic substrate and other commonly used substrate materials. A sealing ring 15 is formed on the first surface of the substrate 3 and surrounds the edge of the first surface of the substrate 3. Figure 2a and Figure 2b The package shell 1 is fixedly connected to the first surface of the substrate 3 through the sealing ring 15 to form a first cavity 2. The second surface of the substrate 3 is formed with a first pad 7 and / or a second pad 9 for providing an electrical connection point, such as Figure 3 The substrate 3 may be a single-layer or multi-layer circuit board, and the first surface of the substrate 3 may also be formed with a circuit structure or an electrical contact portion, such as a solder pad, etc. An electrical connection structure may also be formed inside the substrate 3 to connect the electrical contact portions on the first surface and the second surface of the substrate 3.

[0037] The packaging shell 1 serves as a packaging shell of the vibration sensor packaging structure, which is used to protect the internal electronic components and form a first cavity 2 between the substrate 3. The packaging shell 1 can be made of metal, which is resistant to high temperatures and has a simple production process, and can be mass-produced. In addition, the metal shell packaging shell 1 also has the characteristics of corrosion resistance, electromagnetic shielding, and high mechanical properties, which provide a high degree of protection for the product. In other embodiments, the packaging shell 1 can also be made of other hard materials such as plastic, which is not limited here. The edge of the packaging shell 1 is fixed to the sealing ring 15 on the first surface of the substrate 3 by welding or gluing, so that a first cavity 2 is formed between the packaging shell 1 and the substrate 3.

[0038] The MEMS chip 10 is used as a sensing element for sound signals, and the positions of the diaphragm 11 and the back plate 12 can be interchanged. The bottom of the MEMS chip 10 is fixedly connected to the first surface of the substrate 3 through the colloid 8 .

[0039] refer to Figure 1 The substrate 3 has a first air hole 5 penetrating through the substrate 3. A groove 41 is formed near the first air hole 5 on the first surface of the substrate 3. The groove 41 is connected to the first air hole 5. When the groove 41 extends in the first surface of the substrate 3, it crosses the MEMS chip 10. The groove 41 and the bottom of the MEMS chip 10 form a second air hole, so that the first air hole 5 is connected to the first cavity 2 through the groove 41 (i.e., the second air hole). Figure 2a and Figure 2b The schematic top view of the first surface of the substrate 3 is shown, wherein: Figure 2a The MEMS chip 10 and the application-specific integrated circuit chip 13 are also included. In this specific embodiment, the groove 41 extends in a direction parallel to the length of the side of the substrate 3, and the cross section along the first surface of the substrate 3 is square. In some specific embodiments, the cross section of the groove 41 in a direction parallel to the first surface of the substrate 3 can also be square, circular, polygonal, etc. In some specific embodiments, the cross-sectional shape of the groove 41 in a direction perpendicular to the first surface of the substrate 3 is a trapezoid, a rectangle, an arc or a polygon, etc. The groove 41 only needs to have a bottom lower than the first surface of the substrate 3 and be able to connect the first pore 5 with the first cavity 2. Those skilled in the art can reasonably set the shape of the groove 41. The size of the groove 41 is adjusted according to the size of the second cavity 6 and / or the first pore 5 of the MEMS chip 10.

[0040] In this embodiment, the groove 41 and the bottom of the support structure of the MEMS chip 10 form a second air hole together. In other embodiments, an upwardly recessed through hole is also formed in the support structure of the MEMS chip 10 corresponding to the groove 41, and the groove 41 and the through hole form a second air hole together, thereby increasing the amount of airflow reaching the first cavity through the second air hole.

[0041] In other embodiments, the groove 41 may include multiple grooves distributed under one side of the support structure of the MEMS chip 10, or distributed under multiple side surfaces of the support structure. The side surface here refers to the shape formed by the support structure, such as Figure 2a As shown, the support structure forms a quadrilateral, and the plurality of grooves 41 can be distributed below the four sides of the quadrilateral.

[0042] The MEMS chip 10 includes a second cavity 6 as a back cavity. The pressure sensing layer of the MEMS chip 10 includes a back plate 12 and a diaphragm 11, which are arranged opposite to each other to form a sensing capacitor. When the pressure in the second cavity 6 changes, the pressure sensing layer is deformed, so that the capacitance value changes and a sensing signal is output.

[0043] The support structure of the MEMS chip 10 is fixed to the first surface of the substrate 3 by the colloid 8. When fixing the MEMS chip 10, a certain force is applied to the MEMS chip 10 by the device, so that the bottom of the support structure has a larger contact area with the colloid 8, thereby improving the fixing effect. When the colloid is squeezed, it will overflow to both sides of the bottom of the support structure, overflow to both sides of the support structure, and climb up to a certain height along the outer wall of the MEMS chip 10. Subsequently, the colloid is solidified at a certain temperature and for a certain time, so as to realize the tight connection between the MEMS chip 10 and the substrate 3. However, above the groove 41, there is no colloid 8 at the bottom of the MEMS chip 10, that is, the bottom of the MEMS chip 10 is not sealed and connected to the first surface of the substrate 3 above the groove, so the colloid 8 will not overflow into the groove 41 to block the groove 41.

[0044] Figure 4 A structural diagram showing a vibration sensor packaging structure according to a second embodiment of the present invention; Figure 6a The 3D schematic diagram of the MEMS chip in the vibration sensor packaging structure of the second embodiment of the present invention is shown. Compared with the vibration sensor packaging structure of the first embodiment, the second air hole 4 of the vibration sensor packaging structure of the second embodiment penetrates the support structure of the MEMS chip 10. The similarities are not repeated here, and only the differences are described.

[0045] refer to Figure 4 and Figure 6a In the vibration sensor packaging structure 200 of the second embodiment, the support structure 16 of the MEMS chip 10 has a notch 17 (refer to Figure 6a ), the notch 17 penetrates the support structure 16 and the bottom of the MEMS chip 10. The notch 17 in the MEMS chip 10 and the surface of the substrate 3 form a second air hole 4, and the second air hole 4 connects the first cavity 2 and the second cavity 6, so that the sound signal entering the second cavity 6 from the first air hole 5 can also reach the upper surface of the diaphragm via the second air hole 4 and the first cavity 2.

[0046] In this embodiment, the notch 17 penetrating the support structure 16 of the MEMS chip 10 and the bottom thereof includes one or more notches 17 located in the support structure 16 on at least one side of the MEMS chip 10 .

[0047] Figure 5 A structural diagram showing a vibration sensor packaging structure according to a third embodiment of the present invention; Figure 6a The third embodiment of the present invention shows a three-dimensional schematic diagram of a MEMS chip in a vibration sensor packaging structure. Compared with the vibration sensor packaging structure of the first embodiment or the second embodiment, the second air hole 4 of the vibration sensor packaging structure of the third embodiment penetrates the support structure of the MEMS chip 10 and the surface portion of the substrate 3. The similarities are not repeated here, and only the differences are described.

[0048] refer to Figure 5 and Figure 6a In the vibration sensor packaging structure 300 of the third embodiment, the support structure 16 of the MEMS chip 10 has a notch 17 (refer to Figure 6a ), the notch 17 penetrates the support structure 16 and the bottom of the MEMS chip 10; the substrate 3 below the support structure 16 of the MEMS chip 10 also includes a groove, such as Figure 5 In this embodiment, the notch 17 is, for example, located above the groove, that is, the notch 17 and the groove together form a second air hole 4, and the second air hole 4 connects the first cavity 2 and the second cavity 6, so that the sound signal entering the second cavity 6 from the first air hole 5 can also reach the upper surface of the diaphragm via the second air hole 4 and the first cavity 2.

[0049] In other embodiments, the notch 17 may not correspond to the groove, that is, the notch 17 and the surface of the substrate 3 form a second air hole 4, and the groove and the bottom of the supporting structure 16 of the MEMS chip 10 form a second air hole 4, and the two second air holes 4 are connected to the first cavity 2 and the second cavity 6, so that the sound signal entering the second cavity 6 from the first air hole 5 can also reach the upper surface of the diaphragm via the second air hole 4 and the first cavity 2.

[0050] In other embodiments, the notch 17 that passes through the support structure of the MEMS chip 10 and the bottom thereof includes one or more, and the grooves located in the surface of the substrate 3 in at least one side support structure of the MEMS chip 10 also include one or more. The notch 17 can form the second pore 4 together with the groove in a one-to-one correspondence, or can form the second pores separately without a one-to-one correspondence.

[0051] Figure 6b FIG. 4 is a three-dimensional schematic diagram of a MEMS chip in a vibration sensor packaging structure according to a fourth embodiment of the present invention. Figure 6aCompared with the three-dimensional schematic diagram of the MEMS chip shown, Figure 6b The second air hole in the MEMS chip 10 only passes through the support structure 16 of the MEMS chip 10. The similarities will not be repeated here, and only the differences will be described.

[0052] refer to Figure 6b The three-dimensional schematic diagram of the MEMS chip 10 shown in the figure has a through hole 18 penetrating the support structure 16 in the support structure 16 of the MEMS chip 10, and the peripheral side of the through hole 18 is surrounded by the support structure 16, and the through hole 18 connects the first cavity 2 and the second cavity 6. The shape of the through hole 18 along the side wall surface of the support structure 16 is, for example, any one of square, circular or polygonal.

[0053] In other embodiments, there are one or more through holes 18 penetrating the support structure 16 of the MEMS chip 10 , which are respectively located in the support structure on at least one side of the MEMS chip 10 .

[0054] In other embodiments, the support structure 16 of the MEMS chip 10 has one or more through holes 18, and one or more grooves are also formed in the substrate 3 below the MEMS chip 10. The through holes 18 and the grooves together serve as second air holes in the vibration sensor packaging structure.

[0055] Figure 6c FIG. 5 is a three-dimensional schematic diagram of a MEMS chip in a vibration sensor packaging structure according to a fifth embodiment of the present invention. Figure 6a or Figure 6b Compared with the three-dimensional schematic diagram of the MEMS chip shown, Figure 6c The supporting structure of the MEMS chip 10 has both a notch 17 and a through hole 18. The similarities will not be described here, and only the differences will be described.

[0056] In this embodiment, reference Figure 6c In the support structure 16 of the MEMS chip 10, there is a notch 17 that passes through the bottom of the support structure 16, and a through hole 18 that only passes through the support structure 16. The notch 17 and the through hole 18 are located in the support structure 16 on at least one side of the MEMS chip 10, connecting the first cavity 2 and the second cavity 6.

[0057] In other embodiments, the notch 17 and the through hole 18 each include one or more, and are respectively located in the support structure 16 on at least one side of the MEMS chip 10. Furthermore, the substrate 3 below the MEMS chip 10 also includes one or more grooves, which connect the first air hole 5 and the first cavity 2.

[0058] In another embodiment, at least one through hole 18 , at least one notch 17 and at least one groove collectively serve as a second air hole in the vibration sensor packaging structure.

[0059] When the vibration sensor of the present application is used, the caller makes a sound, and the sound reaches the vibration sensor through two channels: air and vibration. Among them, the sound signal in the air reaches the second cavity 6 of the MEMS chip 10 through the first air hole 5, so that the capacitance value between the diaphragm 11 and the back plate 12 changes, thereby obtaining a sound signal. The sound signal transmitted by vibration reaches the diaphragm 11 and the back plate 12 of the MEMS chip 10 along the structure of the vibration sensor, so that the capacitance value between the diaphragm 11 and the back plate 12 changes, thereby obtaining a sound signal. However, in the vibration sensor, the change in capacitance between the diaphragm 11 and the back plate 12 caused by the sound signal in the air causes noise interference in the sound signal obtained by vibration. In this embodiment, a part of the sound signal in the air reaches the second cavity 6 of the MEMS chip 10 along the first air hole 5, pressing the diaphragm 11 to vibrate, and a part reaches the MEMS chip 10 along the first air hole 5, the second air hole 4 and the first cavity 2, pressing the diaphragm 11 to vibrate from the opposite direction. Due to the same air pressure in two opposite directions acting on the same diaphragm 11, the sound signal in the air is offset. When the sound made by the caller is transmitted through the oral bones to the vibration sensor of the earphone close to the bones, the vibration is transmitted to the substrate 3 of the vibration sensor through the earphone shell and then to the MEMS chip 10, causing the diaphragm 11 on the surface of the MEMS chip 10 to vibrate, forming a parallel plate capacitor with the back plate 12 of the MEMS chip 10, and the integrated circuit chip 13 receives the signal of capacitance change for processing.

[0060] When making a call in a noisy environment, the vibration sensor of the present application can automatically shield the sound signal and only transmit the sound signal transmitted by the bone vibration of the caller when speaking, thereby achieving the highest quality noise reduction.

[0061] In addition, the vibration sensor is not only used for call headsets, but can also be applied to other electronic products that work on the same principle.

[0062] The vibration sensor packaging structure provided by the present invention forms a second air hole in the side wall of the first air hole and / or the second cavity, and the second air hole connects the first air hole and the first cavity, so that the first air hole is not only connected to the second cavity of the sensor, but also connected to the first cavity through the second air hole, so that the surface of the diaphragm in the MEMS chip facing the first cavity can also receive air and pressure, reducing the noise interference brought to the vibration sensor by the sound signal when only the second cavity of the MEMS chip receives air and pressure, thereby improving the yield and reliability of the vibration sensor.

[0063] The vibration sensor packaging structure provided by the present invention forms a second air hole in the side wall of the first air hole and / or the second cavity, and the second air hole connects the first air hole and the first cavity, so that when the sound signal reaches the surface of the diaphragm in the MEMS chip facing the first cavity along the first air hole and the second air hole, the time difference with the time taken for the sound signal to reach the surface of the diaphragm in the MEMS chip facing the second cavity along the first air hole is small, and the sound signals are the same, thereby being able to minimize the noise interference of the sound signal on the vibration sensor.

[0064] The vibration sensor packaging structure of the present application forms a variety of second air holes in the side walls of the first air hole and / or the second cavity to connect the first cavity and the second cavity, including a groove located in the surface of the substrate, a notch located in the MEMS chip and penetrating the bottom of the supporting structure, and a through hole penetrating the supporting structure. When the groove or the notch makes the connection between the first cavity and the second cavity not smooth due to other reasons, the through hole ensures that the sound signal can be transmitted to the upper and lower sides of the diaphragm, thereby reducing interference and improving the reliability of the device.

[0065] According to the embodiments of the present invention as described above, these embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made based on the above description. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and the modified use based on the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A vibration sensor packaging structure, characterized in that: include: A substrate, wherein a first air hole penetrating through the substrate is formed in the substrate; A packaging shell, wherein the packaging shell is fixed to the first surface of the substrate and forms a first cavity with the substrate; A MEMS chip, wherein the MEMS chip is fixed to the first surface of the substrate and is located in the first cavity, and the MEMS chip has a second cavity, and the second cavity is connected to the first pore; Among them, the side wall of the first air hole and / or the second cavity is also formed with a second air hole, and the second air hole connects the first cavity with the first air hole and / or the second cavity, and the sound signal reaching the MEMS chip diaphragm through the first air hole and the sound signal reaching the MEMS chip diaphragm through the second air hole cancel each other out.

2. The vibration sensor packaging structure according to claim 1, characterized in that: The MEMS chip comprises a supporting structure, and a part of the bottom of the supporting structure is fixed on the surface of the substrate through colloid.

3. The vibration sensor packaging structure according to claim 2, characterized in that: At least one groove is formed on the surface of the substrate, and at least one second air hole is formed between the groove and a part of the bottom of the support structure. The second air hole is located below one and / or multiple side surfaces of the support structure.

4. The vibration sensor packaging structure according to claim 2 or 3, characterized in that: At least one notch penetrating through the bottom of the support structure is formed in the support structure, and a second air hole is formed between the notch and a part of the surface of the substrate or a groove on the surface of the substrate.

5. The vibration sensor packaging structure according to claim 4, characterized in that: The notch is located below one and / or more sides of the support structure.

6. The vibration sensor packaging structure according to claim 2 or 3, characterized in that: The MEMS chip is also provided with at least one through hole, and the peripheral side of the through hole is surrounded by the supporting structure to form a second air hole.

7. The vibration sensor packaging structure according to claim 4, characterized in that: The MEMS chip is also provided with at least one through hole, and the peripheral side of the through hole is surrounded by the supporting structure to form a second air hole.

8. The vibration sensor packaging structure according to claim 2, characterized in that: The MEMS chip also includes a diaphragm and a back plate, and the positions of the diaphragm and the back plate are interchangeable.

9. The vibration sensor packaging structure according to claim 1, characterized in that: The cross-sectional shape of the second air hole along the side wall of the first air hole and / or the second cavity includes any one or more of square, circular or polygonal.

10. The vibration sensor packaging structure according to claim 3, characterized in that: The cross-sectional shape of the groove along the direction perpendicular to the first surface of the substrate includes a trapezoid, a rectangle, an arc, and a polygon.

11. The vibration sensor packaging structure according to claim 1, characterized in that: Also includes: ASIC chip, the MEMS chip is electrically connected to the ASIC chip.

12. The vibration sensor packaging structure according to claim 1, characterized in that: The second surface of the substrate includes a first pad and a second pad.

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