MEMS packaging structure and electronic equipment

Abstract

The invention provides an MEMS (Micro Electro Mechanical System) packaging structure and electronic equipment. The MEMS packaging structure comprises a substrate, back electrodes and a vibrating diaphragm, the back electrodes comprise a first back electrode and a second back electrode, the first back electrode is connected with the substrate, and the second back electrode is connected with the side, away from the substrate, of the first back electrode; the vibrating diaphragm is arranged on the back electrode; wherein the first back pole comprises a first sound hole, the second back pole comprises a second sound hole, the central axis of the first sound hole and the central axis of the second sound hole are mutually staggered, and at least part of orthographic projection of the first sound hole towards the vibrating diaphragm coincides with at least part of orthographic projection of the second sound hole towards the vibrating diaphragm. According to the invention, the use performance of the MEMS packaging structure can be improved.

Description

Technical Field

[0001] The present application relates to the field of MEMS packaging technology, and more specifically, to a MEMS packaging structure and electronic equipment. Background Art

[0002] In the prior art, to reduce the acoustic impedance of a MEMS (Micro Electro Mechanical System) package, acoustic holes are typically created on the back of the MEMS package. However, these holes can easily reduce the effective capacitance area of ​​the MEMS package's diaphragm, leading to poor performance.

[0003] Therefore, it is necessary to provide a new technical solution to solve the above technical problems. Summary of the Invention

[0004] One purpose of the present application is to provide a new technical solution for MEMS packaging structure and electronic equipment.

[0005] According to a first aspect of the present application, a MEMS packaging structure is provided, wherein the MEMS packaging structure includes:

[0006] substrate;

[0007] a backpole, a first backpole and a second backpole, wherein the first backpole is connected to the substrate, and the second backpole is connected to a side of the first backpole away from the substrate;

[0008] a diaphragm, the diaphragm being arranged on the back pole;

[0009] The first back pole includes a first sound hole, the second back pole includes a second sound hole, the central axis of the first sound hole and the central axis of the second sound hole are staggered with each other, and at least part of the orthographic projection of the first sound hole toward the diaphragm coincides with at least part of the orthographic projection of the second sound hole toward the diaphragm.

[0010] Optionally, the aperture of the first sound hole is equal to the aperture of the second sound hole.

[0011] Optionally, a plurality of the first sound holes and a plurality of the second sound holes are provided, the plurality of the first sound holes are distributed in a triangular shape on the first back pole, and the plurality of the second sound holes are distributed in a hexagonal shape on the second back pole.

[0012] Optionally, the shape of the first sound hole includes at least one of a circle, an ellipse, a straight-edged ellipse, a square, a hexagon and a cross;

[0013] And / or, the shape of the second sound hole includes at least one of a circle, an ellipse, a straight-edge ellipse, a square, a hexagon and a cross.

[0014] Optionally, the diaphragm includes a first diaphragm and a second diaphragm, the first diaphragm is arranged between the base and the first back pole, and the second diaphragm is arranged on the side of the second back pole away from the first back pole; a first accommodating cavity is formed between the first diaphragm and the second diaphragm, and the first back pole and the second back pole are both arranged in the first accommodating cavity.

[0015] Optionally, the first diaphragm includes a first air-permeable structure, and the second diaphragm includes a second air-permeable structure; the first accommodating cavity can be in communication with the cavity of the substrate through the first air-permeable structure, and the first accommodating cavity can be in communication with the outside through the second air-permeable structure;

[0016] The first back pole and the second back pole can separate the first accommodating cavity into a first sub-chamber connected to the first breathable structure, a second sub-chamber located between the first back pole and the second back pole, and a third sub-chamber connected to the second breathable structure.

[0017] Optionally, connecting columns are also included, and the connecting columns include a first connecting column, a second connecting column, a third connecting column, a fourth connecting column, a fifth connecting column and a sixth connecting column, the first connecting column connects the first back pole and the first diaphragm; the second connecting column connects the second back pole and the second diaphragm; the third connecting column connects the first back pole and the second back pole; the fourth connecting column connects the second back pole and the first diaphragm through the first sound hole; the fifth connecting column connects the first back pole and the second diaphragm through the second sound hole; the sixth connecting column connects the first diaphragm and the second diaphragm through the first sound hole and the second sound hole.

[0018] Optionally, the diaphragm includes a third diaphragm, the third diaphragm is arranged on the side of the second backpole away from the first backpole, a second accommodating cavity is formed between the third diaphragm and the first backpole, and the second backpole is arranged in the second accommodating cavity.

[0019] Optionally, the diaphragm includes a fourth diaphragm, the fourth diaphragm is arranged between the substrate and the first backpole, a third accommodating cavity is formed between the second backpole and the fourth diaphragm, and the first backpole is arranged in the third accommodating cavity.

[0020] According to a second aspect of the present application, an electronic device is provided, comprising a MEMS packaging structure as described in any one of the first aspects.

[0021] The MEMS packaging structure in the present application effectively increases the effective capacitance area of ​​the diaphragm by setting the central axis of the first sound hole and the central axis of the second sound hole to be staggered with each other, and making at least part of the orthographic projection of the first sound hole toward the diaphragm coincide with at least part of the orthographic projection of the second sound hole toward the diaphragm, thereby improving the performance of the MEMS packaging structure.

[0022] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0024] Figure 1 It is a structural diagram of the MEMS packaging structure in the first embodiment of this application.

[0025] Figure 2 This is a schematic structural diagram of the first back electrode in the first embodiment of the present application.

[0026] Figure 3 This is a schematic structural diagram of the second back electrode in the first embodiment of the present application.

[0027] Figure 4 This is a top view of the first back pole and the second back pole in the first embodiment of the present application.

[0028] Figure 5 It is a structural diagram of the first sound hole in the first embodiment of the present application.

[0029] Figure 6 It is a schematic structural diagram of the first sound hole in the second embodiment of the present application.

[0030] Figure 7 It is a structural diagram of the first sound hole in the third embodiment of the present application.

[0031] Figure 8 It is a structural diagram of the first sound hole in the fourth embodiment of the present application.

[0032] Figure 9 It is a structural diagram of the first sound hole in the fifth embodiment of the present application.

[0033] Figure 10 It is a structural diagram of the first sound hole in the sixth embodiment of the present application.

[0034] Figure 11 It is a structural diagram of the MEMS packaging structure in the seventh embodiment of the present application.

[0035] Figure 12It is a structural schematic diagram of the MEMS packaging structure in the eighth embodiment of the present application.

[0036] Figure 13 It is a structural diagram of the MEMS packaging structure in the ninth embodiment of the present application.

[0037] Figure 14 It is a structural diagram of the MEMS packaging structure in the tenth embodiment of the present application.

[0038] Description of reference numerals:

[0039] 1. base; 101. cavity;

[0040] 2. First back pole; 201. First sound hole;

[0041] 3. Second back pole; 301. Second sound hole;

[0042] 4. Diaphragm; 401. First diaphragm; 4011. First air-permeable structure; 402. Second diaphragm; 4021. Second air-permeable structure; 403. Third diaphragm; 404. Fourth diaphragm;

[0043] 5. First insulation layer;

[0044] 6. Second insulation layer;

[0045] 7. First accommodating chamber; 701. First sub-chamber; 702. Second sub-chamber; 703. Third sub-chamber;

[0046] 8. First connecting column;

[0047] 9. Second connecting column;

[0048] 10. The third connecting column;

[0049] 11. Fourth connecting column;

[0050] 12. Fifth connecting column;

[0051] 13. Sixth connecting column;

[0052] 14. Second accommodating chamber;

[0053] 15. The third accommodating chamber. DETAILED DESCRIPTION

[0054] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0055] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be understood as limiting the present application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0056] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of the features. Throughout the description of this application, unless otherwise specified, "plurality" means two or more. Furthermore, "and / or" in the specification and claims refers to at least one of the connected entities, and the character " / " generally indicates an "or" relationship between the connected entities.

[0057] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0058] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0059] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0060] According to one embodiment of the present application, a MEMS packaging structure is provided, which includes a substrate 1, a backpole and a diaphragm 4, the backpole including a first backpole 2 and a second backpole 3, the first backpole 2 is connected to the substrate 1, and the second backpole 3 is connected to the side of the first backpole 2 away from the substrate 1; the diaphragm 4 is arranged on the backpole; wherein, the first backpole 2 includes a first sound hole 201, the second backpole 3 includes a second sound hole 301, the central axis of the first sound hole 201 and the central axis of the second sound hole 301 are staggered with each other, and at least a partial orthographic projection of the first sound hole 201 toward the diaphragm 4 coincides with at least a partial orthographic projection of the second sound hole 301 toward the diaphragm 4.

[0061] Specifically, if Figure 1 As shown, the MEMS packaging structure described in the embodiment of the present application includes a substrate 1, and a cavity 101 penetrating the substrate 1 is provided on the substrate 1, and the cavity 101 is used for sound waves to pass through.

[0062] The first backpole 2 is provided on one side of the substrate 1, and the second backpole 3 is provided on the side of the first backpole 2 facing away from the substrate 1. The first backpole 2 and the second backpole 3 can form a dual backpole structure in the MEMS packaging structure. The dual backpole structure has better linearity in the process of reaching the acoustic overload point. Compared with the traditional single backpole MEMS packaging structure, the sound pressure level at which the audio begins to distort is increased by nearly 10dB, thereby further reducing the distortion of the MEMS packaging structure, making the use effect of the MEMS packaging structure better. Furthermore, the dual backpole structure can also optimize the frequency response of the MEMS packaging structure, so that the MEMS packaging structure has a flatter response characteristic in a wider frequency range.

[0063] The MEMS packaging structure also includes a diaphragm 4. One diaphragm 4 is provided. One diaphragm 4 can be provided between the substrate 1 and the first backpole 2, or one diaphragm 4 can also be provided on the side of the second backpole 3 away from the first backpole 2, or one diaphragm 4 can also be provided between the first backpole 2 and the second backpole 3. Of course, two diaphragms 4 can also be provided. For example, the diaphragm 4 can include a first diaphragm 401 and a second diaphragm 402. The first diaphragm 401 is provided between the substrate 1 and the first backpole 2, and the second diaphragm 402 is provided on the side of the second backpole 3 away from the first backpole 2; or, the first diaphragm 401 is provided between the substrate 1 and the first backpole 2, and the second diaphragm 402 is provided between the first backpole 2 and the second backpole 3; or, the first diaphragm 401 is provided between the first backpole 2 and the second backpole 3, and the second diaphragm 402 is provided on the side of the second backpole 3 away from the first backpole 2.

[0064] The diaphragm 4 can vibrate under the action of external sound waves. A receiving cavity is formed between the diaphragm 4, the first backpole 2, and the second backpole 3. The diaphragm 4, the first backpole 2, the second backpole 3, and the receiving cavity can form a capacitor structure.

[0065] Therefore, when external sound waves act on the diaphragm 4, the diaphragm 4 can vibrate, and the distance between the diaphragm 4 and the first back pole 2 and the second back pole 3 changes, thereby causing the capacitance value of the capacitor structure to change, thereby converting the sound signal into an electrical signal.

[0066] In which, a fixed voltage is set between the diaphragm 4 and the first back pole 2 and the second back pole 3. The voltage can make the capacitor structure have an initial capacitance value, and the voltage can also keep the charge unchanged when the diaphragm 4 vibrates, thereby ensuring that the capacitance change of the capacitor structure can accurately reflect the change of the sound wave.

[0067] In addition, if Figure 2 and Figure 3 As shown, the first back pole 2 is provided with a first sound hole 201 , and the second back pole 3 is provided with a second sound hole 301 . The first sound hole 201 and the second sound hole 301 are used for allowing external sound waves to pass through so that the external sound waves can act on the diaphragm 4 .

[0068] Among them, Figure 4As shown, the orthographic projection of the central axis of the first sound hole 201 toward the second back pole 3 can be located in the non-sound hole area of ​​the second back pole 3, or the orthographic projection of the central axis of the second sound hole 301 toward the first back pole 2 can be located in the non-sound hole area on the first back pole 2, thereby achieving the central axis of the first sound hole 201 and the central axis of the second sound hole 301 being staggered with each other.

[0069] Of course, in other embodiments, the central axis of the first sound hole 201 may also pass through the second sound hole 301. At this time, the orthographic projection of the central axis of the first sound hole 201 toward the diaphragm 4 may not coincide with the orthographic projection of the central axis of the second sound hole 301 toward the diaphragm 4. In this way, the central axis of the first sound hole 201 and the central axis of the second sound hole 301 can also be staggered with each other.

[0070] In addition, if Figure 4 As shown, at least part of the first sound hole 201 can be connected with at least part of the second sound hole 301. For example, at least part of one first sound hole 201 can be connected with at least part of one second sound hole 301, or at least part of one first sound hole 201 can be connected with at least part of multiple second sound holes 301, or at least part of multiple first sound holes 201 can be connected with at least part of one second sound hole 301, or at least part of multiple first sound holes 201 can be connected with at least part of multiple second sound holes 301, so as to achieve the overlap of at least part of the orthographic projection of the first sound hole 201 toward the diaphragm 4 and at least part of the orthographic projection of the second sound hole 301 toward the diaphragm 4.

[0071] Thus, the present application, on the one hand, increases the effective capacitance area of ​​the diaphragm 4 by staggering the central axis of the first sound hole 201 and the central axis of the second sound hole 301, effectively avoiding the situation where the capacitance variation of the capacitance structure is poor due to an excessively large electric field-free region of the diaphragm 4. On the other hand, by aligning at least part of the orthographic projection of the first sound hole 201 onto the diaphragm 4 with at least part of the orthographic projection of the second sound hole 301 onto the diaphragm 4, external sound waves can smoothly pass through the first sound hole 201 and the second sound hole 301, effectively reducing the acoustic impedance of the MEMS packaging structure. This effectively improves the performance of the MEMS packaging structure.

[0072] In other embodiments, since the apertures of the first sound hole 201 and the second sound hole 301 are too large, impurities in the external environment will pass through the first back pole 2 and the second back pole 3 to damage the diaphragm 4 and the substrate 1, and the apertures of the first sound hole 201 and the second sound hole 301 are too small, which will increase the acoustic resistance of the MEMS packaging structure. Therefore, in order to avoid the above problems, the present application preferably adopts the apertures of the first sound hole 201 and the second sound hole 301 to be 5μm to 30μm.

[0073] Of course, the apertures of the first sound hole 201 and the second sound hole 301 of the present application can also be set to other sizes, and those skilled in the art can choose according to actual needs. The present application does not make any specific restrictions here.

[0074] In one embodiment, the aperture of the first sound hole 201 is equal to the aperture of the second sound hole 301 .

[0075] Specifically, if Figures 2 to 4 As shown, the embodiment of the present application simplifies the difficulty of setting the central axis of the first sound hole 201 and the central axis of the second sound hole 301 to be staggered with each other by setting the aperture of the first sound hole 201 to be equal to the aperture of the second sound hole 301, thereby increasing the effective capacitance area of ​​the diaphragm 4; on the other hand, it also reduces the noise generated by the structural differences of the sound holes, improves the signal-to-noise ratio of the MEMS packaging structure, and enhances the quality of the sound signal generated by the MEMS packaging structure; on the other hand, since the aperture of the sound hole directly affects the transmission efficiency and acoustic resistance of the sound wave, the present application sets the aperture of the first sound hole 201 to be equal to the aperture of the second sound hole 301, thereby making the acoustic resistance of the MEMS packaging structure more consistent, thereby not only reducing the acoustic resistance of the MEMS packaging structure, but also reducing the attenuation and reflection of the sound signal caused by the difference in acoustic resistance.

[0076] Of course, in other embodiments, the aperture of the first sound hole 201 may also be smaller or larger than the aperture of the second sound hole 301, as long as the central axis of the first sound hole 201 and the central axis of the second sound hole 301 are staggered with each other, and as long as at least part of the orthographic projection of the first sound hole 201 toward the diaphragm 4 and at least part of the orthographic projection of the second sound hole 301 toward the diaphragm 4 coincide with each other, those skilled in the art may make a choice according to actual needs, and this application does not impose any specific restrictions here.

[0077] In one embodiment, a plurality of the first sound holes 201 and a plurality of the second sound holes 301 are provided. The plurality of first sound holes 201 are distributed in a triangle on the first back pole 2 , and the plurality of second sound holes 301 are distributed in a hexagon on the second back pole 3 .

[0078] Specifically, if Figures 2 to 4 As shown, the embodiment of the present application effectively simplifies the difficulty of setting the central axis of the first sound hole 201 and the central axis of the second sound hole 301 to be staggered from each other, and simplifies the difficulty of setting at least part of the orthographic projection of the first sound hole 201 toward the diaphragm 4 to coincide with at least part of the orthographic projection of the second sound hole 301 toward the diaphragm 4 by arranging multiple first sound holes 201 to be distributed in a triangular shape on the first back pole 2, and arranging multiple second sound holes 301 to be distributed in a hexagonal shape on the second back pole 3.

[0079] In addition, the present application arranges multiple first sound holes 201 distributed in a triangular shape on the first back pole 2, so that the first sound holes 201 can be evenly covered on the first back pole 2, thereby further reducing the unevenness of the sound waves during the propagation process. Moreover, the triangular distribution of multiple first sound holes 201 can also better disperse the sound pressure, thereby further reducing the high-frequency noise generated by the MEMS packaging structure.

[0080] In addition, the present application improves the transmission efficiency of sound waves by arranging multiple second sound holes 301 distributed in a hexagonal pattern on the second back pole 3, thereby further enhancing the sensitivity of the MEMS packaging structure. Moreover, the hexagonal distribution of multiple second sound holes 301 also effectively reduces the acoustic resistance of the MEMS packaging structure, thereby further enhancing the penetration ability of sound waves.

[0081] In other embodiments, multiple first sound holes 201 can also be distributed in a hexagonal shape on the first back pole 2, and multiple second sound holes 301 can also be distributed in a triangular shape on the second back pole 3. Those skilled in the art can make a choice according to actual needs, and this application does not make any specific restrictions here.

[0082] In one embodiment, the shape of the first sound hole 201 includes at least one of a circle, an ellipse, a straight-edged ellipse, a square, a hexagon and a cross; and / or the shape of the second sound hole 301 includes at least one of a circle, an ellipse, a straight-edged ellipse, a square, a hexagon and a cross.

[0083] Specifically, if Figures 5 to 10As shown, the embodiment of the present application effectively improves and simplifies the difficulty of setting the central axis of the first sound hole 201 and the central axis of the second sound hole 301 to be staggered with each other, and simplifies the difficulty of setting at least part of the orthographic projection of the first sound hole 201 toward the diaphragm 4 to coincide with at least part of the orthographic projection of the second sound hole 301 toward the diaphragm 4 by setting the shape of the first sound hole 201 to be at least one of a circle, an ellipse, a straight-edged ellipse, a square, a hexagon and a cross, and setting the shape of the second sound hole 301 to be at least one of a circle, an ellipse, a straight-edged ellipse, a square, a hexagon and a cross.

[0084] In one embodiment, the diaphragm 4 includes a first diaphragm 401 and a second diaphragm 402, the first diaphragm 401 is arranged between the substrate 1 and the first back pole 2, and the second diaphragm 402 is arranged on the side of the second back pole 3 away from the first back pole 2; a first accommodating cavity 7 is formed between the first diaphragm 401 and the second diaphragm 402, and the first back pole 2 and the second back pole 3 are both arranged in the first accommodating cavity 7.

[0085] Specifically, if Figure 1 As shown, in the embodiment of the present application, a first diaphragm 401 is provided between the substrate 1 and the first back pole 2, and a second diaphragm 402 is provided on the side of the second back pole 3 facing away from the first back pole 2, thereby forming a dual-diaphragm structure in the MEMS package structure. The dual-diaphragm structure can not only more accurately capture sound details through two independent diaphragms 4, making the MEMS package structure more sensitive, but also enable the MEMS package structure to capture a wider frequency range, so that the MEMS package structure has a richer and more comprehensive sound performance.

[0086] The first accommodating cavity 7 is formed between the first diaphragm 401 and the second diaphragm 402, and the first back electrode 2 and the second back electrode 3 are both disposed in the first accommodating cavity 7. Thus, in the present application, the first diaphragm 401, the second diaphragm 402, the first back electrode 2, the second back electrode 3, and the first accommodating cavity 7 form a capacitor structure, enabling the capacitor structure to better convert sound signals into electrical signals, thereby effectively improving the performance of the MEMS packaging structure.

[0087] In addition, in order to further improve the insulation performance between the first backpole 2, the second backpole 3, the first diaphragm 401 and the second diaphragm 402, the MEMS packaging structure described in the present application also includes a first insulating layer 5, and the first insulating layer 5 can be arranged between the first diaphragm 401 and the first backpole 2, between the first backpole 2 and the second backpole 3, and between the second backpole 3 and the second diaphragm 402.

[0088] In addition, in order to ensure the insulation performance of the substrate 1, the MEMS packaging structure described in this application also includes a second insulating layer 6, which can be arranged between the first diaphragm 401 and the substrate 1, or the second insulating layer 6 can be arranged between the first back pole 2 and the substrate 1.

[0089] In one embodiment, the first diaphragm 401 includes a first breathable structure 4011, and the second diaphragm 402 includes a second breathable structure 4021; the first accommodating cavity 7 can be connected to the cavity 101 of the substrate 1 through the first breathable structure 4011, and the first accommodating cavity 7 can be connected to the outside world through the second breathable structure 4021; wherein, the first back pole 2 and the second back pole 3 can separate the first accommodating cavity 7 into a first sub-chamber 701 connected to the first breathable structure 4011, a second sub-chamber 702 located between the first back pole 2 and the second back pole 3, and a third sub-chamber 703 connected to the second breathable structure 4021.

[0090] Specifically, if Figure 11 As shown, the embodiment of the present application provides a first air-permeable structure 4011 on the first diaphragm 401 and a second air-permeable structure 4021 on the second diaphragm 402, so that the first accommodating cavity 7 can be connected with the cavity 101 of the substrate 1 through the first air-permeable structure 4011, and connected with the outside world through the second air-permeable structure 4021, thereby effectively reducing the reflection and interference of sound waves on the first diaphragm 401 and the second diaphragm 402, improving the penetration of sound waves, and making the sensitivity and linearity of the MEMS packaging structure higher.

[0091] The first backpole 2 and the second backpole 3 can both be disposed in the first accommodating chamber 7, and the first backpole 2 and the second backpole 3 can separate the first accommodating chamber 7 into a first sub-chamber 701 communicating with the first air-permeable structure 4011, a second sub-chamber 702 located between the first backpole 2 and the second backpole 3, and a third sub-chamber 703 communicating with the second air-permeable structure 4021. Thus, since the first backpole 2 is provided with the first sound hole 201 and the second backpole 3 is provided with the second sound hole 301, the present application further improves the penetration of sound waves through the interaction of the first sound hole 201, the second sound hole 301, the first air-permeable structure 4011, and the second air-permeable structure 4021.

[0092] In one embodiment, the MEMS packaging structure also includes connecting columns, which include a first connecting column 8, a second connecting column 9, a third connecting column 10, a fourth connecting column 11, a fifth connecting column 12 and a sixth connecting column 13, wherein the first connecting column 8 connects the first back pole 2 and the first diaphragm 401; the second connecting column 9 connects the second back pole 3 and the second diaphragm 402; the third connecting column 10 connects the first back pole 2 and the second back pole 3; the fourth connecting column 11 passes through the first sound hole 201 to connect the second back pole 3 and the first diaphragm 401; the fifth connecting column 12 passes through the second sound hole 301 to connect the first back pole 2 and the second diaphragm 402; the sixth connecting column 13 passes through the first sound hole 201 and the second sound hole 301 to connect the first diaphragm 401 and the second diaphragm 402.

[0093] Specifically, if Figure 12 As shown, the embodiment of the present application connects the first back pole 2, the second back pole 3, the first diaphragm 401 and the second diaphragm 402 in pairs through the connecting column, which on the one hand enhances the stability and reliability of the MEMS packaging structure; on the other hand, it effectively reduces the reflection and interference of sound waves between the back pole and the diaphragm 4, and further improves the linearity and consistency of the MEMS packaging structure; on the other hand, it can also adjust the acoustic impedance of the MEMS packaging structure to optimize the acoustic performance of the MEMS packaging structure.

[0094] Among them, the number and arrangement of the first connecting column 8, the second connecting column 9, the third connecting column 10, the fourth connecting column 11, the fifth connecting column 12 and the sixth connecting column 13 can be selected by those skilled in the art according to actual needs, and this application does not impose any specific restrictions here.

[0095] In addition, the material of the connecting column may include at least one of a conductor, a semiconductor and an insulator. Those skilled in the art may make a selection according to actual needs, and this application does not impose any specific restrictions here.

[0096] In one embodiment, the diaphragm 4 includes a third diaphragm 403, which is arranged on the side of the second back pole 3 away from the first back pole 2, and a second accommodating cavity 14 is formed between the third diaphragm 403 and the first back pole 2, and the second back pole 3 is arranged in the second accommodating cavity 14.

[0097] Specifically, if Figure 13 As shown, in the embodiment of the present application, a second accommodating cavity 14 is formed between the third diaphragm 403 and the first backpole 2 , so that the third diaphragm 403 , the first backpole 2 , the second backpole 3 and the second accommodating cavity 14 can constitute a capacitor structure.

[0098] Therefore, since the first back pole 2 is provided with a first sound hole 201 and the second back pole 3 is provided with a second sound hole 301, it not only effectively avoids the situation where the electric field-free area of ​​the diaphragm 4 is too large, resulting in poor capacitance change of the capacitor structure, but also effectively reduces the acoustic impedance of the MEMS packaging structure, thereby improving the performance of the MEMS packaging structure.

[0099] The third diaphragm 403 may also be provided with a third air-permeable structure (not shown), and the second accommodating cavity 14 may be connected to the outside world through the third air-permeable structure. Thus, the present application can further improve the penetration of sound waves through the interaction of the first sound hole 201, the second sound hole 301, and the third air-permeable structure.

[0100] In one embodiment, the diaphragm 4 includes a fourth diaphragm 404, which is arranged between the substrate 1 and the first backpole 2; a third accommodating cavity 15 is formed between the second backpole 3 and the fourth diaphragm 404, and the first backpole 2 is arranged in the third accommodating cavity 15.

[0101] Specifically, if Figure 14 As shown, in the embodiment of the present application, the third accommodating cavity 15 is formed between the second backpole 3 and the fourth diaphragm 404, so that the fourth diaphragm 404, the first backpole 2, the second backpole 3 and the third accommodating cavity 15 can form a capacitor structure.

[0102] Therefore, since the first back pole 2 is provided with a first sound hole 201 and the second back pole 3 is provided with a second sound hole 301, it not only effectively avoids the situation where the electric field-free area of ​​the diaphragm 4 is too large, resulting in poor capacitance change of the capacitor structure, but also effectively reduces the acoustic impedance of the MEMS packaging structure, thereby improving the performance of the MEMS packaging structure.

[0103] The fourth diaphragm 404 includes a fourth air-permeable structure (not shown), and the third accommodating cavity 15 is connected to the outside world through the fourth air-permeable structure. Thus, the present application can further improve the penetration of sound waves through the interaction between the first sound hole 201, the second sound hole 301, and the fourth air-permeable structure.

[0104] According to another embodiment of the present application, an electronic device is provided, which includes the MEMS packaging structure described in the present application.

[0105] Specifically, the electronic device described in the embodiments of the present application can be any one of a mobile phone, a tablet computer, a personal digital assistant, a television, a smart wearable product, a virtual reality terminal device, an augmented reality terminal device, a rechargeable small household appliance (such as a soy milk maker, a sweeping robot), a drone, a radar, aerospace equipment and a vehicle-mounted device.

[0106] The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0107] Although some specific embodiments of the present application have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A MEMS packaging structure, characterized in that: include: substrate (1); A backpole, the backpole comprising a first backpole (2) and a second backpole (3), the first backpole (2) being connected to the substrate (1), and the second backpole (3) being connected to a side of the first backpole (2) facing away from the substrate (1); a diaphragm (4), the diaphragm (4) being arranged on the back pole; The first backpole (2) includes a first sound hole (201), the second backpole (3) includes a second sound hole (301), the central axis of the first sound hole (201) and the central axis of the second sound hole (301) are staggered, and at least a portion of the orthographic projection of the first sound hole (201) toward the diaphragm (4) coincides with at least a portion of the orthographic projection of the second sound hole (301) toward the diaphragm (4).

2. The MEMS packaging structure according to claim 1, wherein: The aperture of the first sound hole (201) is equal to the aperture of the second sound hole (301).

3. The MEMS packaging structure according to claim 1, wherein: A plurality of the first sound holes (201) and the second sound holes (301) are provided, wherein the plurality of the first sound holes (201) are distributed in a triangular shape on the first back pole (2), and the plurality of the second sound holes (301) are distributed in a hexagonal shape on the second back pole (3).

4. The MEMS packaging structure according to claim 1, wherein: The shape of the first sound hole (201) includes at least one of a circle, an ellipse, a straight-edge ellipse, a square, a hexagon and a cross; And / or, the shape of the second sound hole (301) includes at least one of a circle, an ellipse, a straight-edge ellipse, a square, a hexagon and a cross.

5. The MEMS packaging structure according to claim 1, wherein: The diaphragm (4) comprises a first diaphragm (401) and a second diaphragm (402), wherein the first diaphragm (401) is arranged between the substrate (1) and the first backpole (2), and the second diaphragm (402) is arranged on the side of the second backpole (3) facing away from the first backpole (2); a first accommodating cavity (7) is formed between the first diaphragm (401) and the second diaphragm (402), and the first backpole (2) and the second backpole (3) are both arranged in the first accommodating cavity (7).

6. The MEMS packaging structure according to claim 5, characterized in that: The first diaphragm (401) includes a first air-permeable structure (4011), and the second diaphragm (402) includes a second air-permeable structure (4021); the first accommodating cavity (7) can be communicated with the cavity (101) of the substrate (1) through the first air-permeable structure (4011), and the first accommodating cavity (7) can be communicated with the outside world through the second air-permeable structure (4021); The first back pole (2) and the second back pole (3) are capable of dividing the first accommodating cavity (7) into a first sub-chamber (701) connected to the first breathable structure (4011), a second sub-chamber (702) located between the first back pole (2) and the second back pole (3), and a third sub-chamber (703) connected to the second breathable structure (4021).

7. The MEMS packaging structure according to claim 5, characterized in that: The invention also includes connecting columns, which include a first connecting column (8), a second connecting column (9), a third connecting column (10), a fourth connecting column (11), a fifth connecting column (12) and a sixth connecting column (13), wherein the first connecting column (8) connects the first back pole (2) and the first diaphragm (401); the second connecting column (9) connects the second back pole (3) and the second diaphragm (402); the third connecting column (10) connects the first back pole (2) and the second back pole (3); the fourth connecting column (11) passes through the first sound hole (201) to connect the second back pole (3) and the first diaphragm (401); the fifth connecting column (12) passes through the second sound hole (301) to connect the first back pole (2) and the second diaphragm (402); and the sixth connecting column (13) passes through the first sound hole (201) and the second sound hole (301) to connect the first diaphragm (401) and the second diaphragm (402).

8. The MEMS packaging structure according to claim 1, wherein: The diaphragm (4) includes a third diaphragm (403), the third diaphragm (403) is arranged on the side of the second backpole (3) away from the first backpole (2), a second accommodating cavity (14) is formed between the third diaphragm (403) and the first backpole (2), and the second backpole (3) is arranged in the second accommodating cavity (14).

9. The MEMS packaging structure according to claim 1, wherein: The diaphragm (4) includes a fourth diaphragm (404), the fourth diaphragm (404) is arranged between the substrate (1) and the first backpole (2), a third accommodating cavity (15) is formed between the second backpole (3) and the fourth diaphragm (404), and the first backpole (2) is arranged in the third accommodating cavity (15).

10. An electronic device, characterized in that: The MEMS packaging structure comprises the MEMS packaging structure according to any one of claims 1 to 9.

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