Sensor packaging structure and electronic equipment
By designing a labyrinthine venting channel in the sensor packaging structure, the problems of structural cracking and dust ingress caused by air pressure changes were solved, achieving air pressure balance and acoustic isolation, thus improving the stability and reliability of the sensor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GOERTEK MICROELECTRONICS CO LTD
- Filing Date
- 2025-04-21
- Publication Date
- 2026-04-24
AI Technical Summary
The sensor packaging structure is prone to cracking or failure of the welding interface when the air pressure changes, and the air vents allow dust and moisture to enter, affecting the stability and acoustic performance of the sensor.
A labyrinthine venting channel is designed, which forms a labyrinthine sealing path through the bending structure in the substrate, extending the airflow path and reducing the probability of dust entering, while also forming a non-linear sound wave propagation path to enhance the acoustic isolation effect.
Achieving air pressure balance prevents packaging structure failure, reduces the probability of dust ingress, enhances acoustic isolation, and improves sensor stability and reliability.
Smart Images
Figure CN224160394U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of sensor equipment technology, specifically to a sensor packaging structure and electronic equipment. Background Technology
[0002] As a core component for information acquisition, sensors are widely used in fields such as pressure detection, inertial measurement, and acoustic recognition. In technology platforms such as microelectromechanical systems (MEMS), sensor structures typically employ a cavity structure formed by a sealed substrate and housing to protect the internal chip and maintain detection accuracy.
[0003] However, after packaging, the internal cavity of the sensor is often in a sealed state. When the device experiences thermal changes such as reflow soldering or high and low temperature cycling, the air pressure inside the package cavity will fluctuate due to thermal expansion and contraction. If the air pressure changes drastically, it may cause the package structure to crack under pressure or the solder interface to fail, thus affecting the stability and lifespan of the sensor. Therefore, to alleviate the structural stress caused by the difference in internal and external air pressure, some existing solutions set vent holes on the sensor shell to achieve air pressure balance. However, setting vent holes also introduces new problems. On the one hand, vent holes may become channels for external dust, moisture and other impurities to enter the cavity, affecting the normal operation of the chip; on the other hand, in some sensor applications that require acoustic isolation (such as bone conduction voiceprint recognition), vent holes may also damage the acoustic sealing performance, leading to detection errors. In addition, although some products compensate through post-processing of hole plugging, hole plugging has the risks of failure such as complex processes, incomplete plugging, and material aging, which increases manufacturing costs and reliability risks. Utility Model Content
[0004] The purpose of this invention is to at least solve the problem that dust or sound waves may enter the sensor cavity through the venting channel when pressure balance is achieved. This purpose is achieved through the following technical solution:
[0005] The first aspect of this utility model provides a sensor packaging structure, comprising:
[0006] A substrate, wherein the substrate is provided with a first through hole and a second through hole;
[0007] An outer casing, which covers the substrate and encloses it to form an encapsulation cavity;
[0008] A venting channel is formed within the substrate. The venting channel is connected to the packaging cavity through the first through hole and to the outside through the second through hole. The portion of the venting channel located between the first through hole and the second through hole has at least two bends.
[0009] According to the sensor packaging structure of this utility model, the venting channel is located inside the substrate and has at least two bends between the first and second through holes, thus forming a labyrinthine sealing path. This effectively extends the airflow path while enabling gas conduction between the packaging cavity and the external environment, causing external particles to undergo multiple changes in direction and velocity attenuation within the venting channel, reducing the probability of dust entering the packaging cavity. Simultaneously, the venting channel constitutes a non-linear sound wave propagation path, which can induce multiple reflections and energy dissipation during sound wave propagation, enhancing the acoustic isolation effect of the packaging cavity. Furthermore, the venting channel maintains gas conductivity, enabling internal pressure balance when the ambient air pressure of the sensor fluctuates significantly, preventing packaging structure failure or malfunction.
[0010] In addition, the sensor packaging structure of this utility model may also have the following additional technical features:
[0011] In some embodiments of this utility model, the substrate is provided with a first shielding part and a second shielding part, the first shielding part and the second shielding part are located in the venting channel and are interlocked with each other to form at least two bending structures.
[0012] In some embodiments of this utility model, the first blocking part includes a plurality of first strip-shaped protrusions, and the second blocking part includes a plurality of second strip-shaped protrusions. The plurality of first strip-shaped protrusions and the plurality of second strip-shaped protrusions are alternately arranged in sequence along a first direction and interlock with each other to form the bending structure. The first direction is the direction from the first through hole to the second through hole.
[0013] In some embodiments of this utility model, the substrate is provided with a plurality of arc-shaped grooves, which are arranged in a concentric circle and along the radial direction of the concentric circle. Two adjacent arc-shaped grooves along the radial direction are connected through an opening, so that the plurality of arc-shaped grooves form the bending structure.
[0014] In some embodiments of this utility model, two adjacent openings along the radial direction have an included angle along the circumferential direction of concentric circles, the included angle being greater than 0° and less than 180°.
[0015] In some embodiments of this utility model, the substrate has a first side and a second side arranged opposite to each other, the first through hole is disposed near the first side, and the second through hole is disposed near the second side.
[0016] In some embodiments of this utility model, the encapsulation cavity contains a MEMS chip and an ASIC chip.
[0017] In some embodiments of this utility model, the substrate and the outer shell are connected by the connection structure.
[0018] In some embodiments of this utility model, the venting channel has a cross-section perpendicular to its own extending direction, and the cross-section is circular.
[0019] A second aspect of this invention provides an electronic device comprising the aforementioned sensor packaging structure. Attached Figure Description
[0020] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0021] Figure 1 A schematic diagram of the sensor packaging structure according to an embodiment of the present invention is shown.
[0022] Figure 2 A schematic diagram of the venting channel according to the first embodiment of the present invention is shown.
[0023] Figure 3 A schematic diagram of the venting channel according to the second embodiment of the present invention is shown.
[0024] The attached figures are labeled as follows:
[0025] 100. Sensor packaging structure; 1001. Packaging cavity;
[0026] 10. Substrate; 101. First through hole; 102. Second through hole; 11. Vent channel; 111. First shielding part; 112. Second shielding part; 12. First side; 13. Second side;
[0027] 20. Outer shell; 30. Connection structure; 40. MEMS chip; 50. ASIC chip. Detailed Implementation
[0028] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
[0029] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.
[0030] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.
[0031] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations.
[0032] like Figures 1 to 3 As shown, according to an embodiment of the present invention, a sensor packaging structure 100 is proposed, including a substrate 10 and a shell 20. The substrate 10 is provided with a first through hole 101 and a second through hole 102, and a venting channel 11 is formed in the substrate 10, which is respectively connected to the first through hole 101 and the second through hole 102. The portion of the venting channel 11 located between the first through hole 101 and the second through hole 102 has at least two bending structures to form a labyrinth-type sealing structure.
[0033] According to the sensor packaging structure 100 of this embodiment, the venting channel 11 is disposed inside the substrate 10 and has at least two bends between the first through hole 101 and the second through hole 102, thereby forming a labyrinthine sealing path. This effectively extends the airflow path while enabling gas conduction between the packaging cavity 1001 and the external environment, causing external particles to undergo multiple changes in direction and velocity attenuation within the venting channel 11, reducing the probability of dust entering the packaging cavity 1001. Simultaneously, the venting channel 11 constitutes a non-linear sound wave propagation path, which can induce multiple reflections and energy dissipation during sound wave propagation, enhancing the acoustic isolation effect of the packaging cavity 1001. Furthermore, the venting channel 11 maintains gas conductivity, enabling internal pressure balance when the ambient air pressure of the sensor fluctuates significantly, preventing packaging structure failure or malfunction.
[0034] In some embodiments, the substrate 10 is provided with a first shielding portion 111 and a second shielding portion 112. The first shielding portion 111 and the second shielding portion 112 are located within the venting channel 11 and are interlocked to form at least two bent structures. By providing the first shielding portion 111 and the second shielding portion 112 in the venting channel 11 and forming at least two bent path segments by interlocking with each other, the venting channel 11 can have a non-straight-through labyrinth structure. While ensuring the air pressure balance function between the encapsulation cavity 1001 and the outside world, it significantly extends the gas propagation path and improves the filtering and blocking ability of dust and particles. At the same time, since the propagation path of sound waves in the comb-tooth interlaced structure is discontinuous, multiple reflections, interferences and energy attenuation are likely to occur, thereby effectively enhancing the acoustic impedance of the venting channel 11 and playing a role in suppressing external noise interference with the operation of the sensor.
[0035] like Figure 2 As shown, specifically, the first blocking portion 111 includes a plurality of first strip-shaped protrusions, and the second blocking portion 112 includes a plurality of second strip-shaped protrusions, along a first direction (e.g., Figure 2(In the direction of arrow a), multiple first strip-shaped protrusions and multiple second strip-shaped protrusions are staggered and interlocked in a first direction to form a bent structure. This first direction is the direction from the first through hole 101 to the second through hole 102. The venting channel 11 is manufactured using a lamination process. Further, the substrate 10 includes an upper substrate 10 and a lower substrate 10 laminated together. The upper substrate 10 is provided with multiple first strip-shaped protrusions, which are arranged in a preset direction to form a first shielding portion 111. The lower substrate 10 is provided with multiple second strip-shaped protrusions, which are arranged opposite to the first strip-shaped protrusions and staggered in the same direction to form a second shielding portion 112. During the lamination process, the first strip-shaped protrusions and the second strip-shaped protrusions are precisely aligned and interlocked, forming multiple staggered gaps between them, constituting a non-straight bent venting path. The venting path extends between the first through-hole 101 and the second through-hole 102, forming at least two directional change structures along the first direction, thereby constituting a venting channel 11 with a comb-like labyrinth structure. Therefore, the venting channel 11 not only achieves the function of balancing the air pressure between the encapsulation cavity 1001 and the external environment, but also effectively restricts the direct entry of external dust particles by means of the staggered strip-shaped protrusion structure, and attenuates the sound wave propagation path, thereby improving the protective performance and acoustic isolation capability of the entire encapsulation structure.
[0036] Specifically, the first shielding portion 111 includes multiple protrusions arranged along a wavy contour, and the second shielding portion 112 includes multiple wavy grooves corresponding to the first direction. The wavy protrusions and wavy grooves are structurally interlocked to form a non-linear continuous channel segment extending along the first direction, and constitute a path with multiple directional changes in the venting channel 11. This venting channel 11 can enhance the number of sound wave reflections along the venting path, thereby improving the acoustic impedance effect of the encapsulation structure, and possessing strong gas release capability and particle barrier function.
[0037] Specifically, the first shielding part 111 includes multiple serrated convex segments, with sharp-angled recessed areas formed between adjacent convex segments. The second shielding part 112 has a corresponding reverse serrated structure and fits into it. The two sets of serrations are staggered in the first direction, and the airflow needs to pass through multiple reflective segments with abrupt changes in angle in the venting channel 11, which can achieve particle collision deflection and sound wave attenuation multiple times, effectively improving the protection capability of the venting path.
[0038] Specifically, the first shielding portion 111 is a plurality of slit-shaped through holes formed on a certain layer of the substrate 10, and the second shielding portion 112 is a shielding plate segment or a closed protrusion disposed on the mating layer. After the substrate 10 is assembled by lamination or packaging, the slit-shaped through holes and the corresponding shielding structure form a long and curved air-guiding channel unit. This embodiment is suitable for flexible circuit boards, MEMS chip 40 packages, or micro sensors, and can achieve strong air pressure balance and protection functions while maintaining the micro structure.
[0039] like Figure 3 As shown, in some embodiments, the substrate 10 has multiple arc-shaped grooves arranged concentrically in the radial direction of the concentric circles. That is, with a central point as the center, multiple arc-shaped grooves are arranged sequentially around the substrate, spiraling outwards radially. Two adjacent arc-shaped grooves in the radial direction are connected by an opening, and there is an angle between two adjacent openings in the radial direction along the circumferential direction of the concentric circles, the angle being greater than 0° and less than 180°. Two adjacent arc-shaped grooves are connected by openings located at their ends or sidewalls. These openings allow gas to pass through the opening into the next outermost arc-shaped groove after completing one arc-shaped path, thus creating a spiral-shaped venting channel 11 structure along the circumferential direction. Furthermore, an angle is provided between any two adjacent openings along the circumferential direction of the concentric circles. This angle ensures that the channel path has multiple directional changes, rather than a straight channel path, effectively lengthening the airflow path.
[0040] Specifically, the aforementioned arc-shaped groove and its connecting opening are preferably formed using an etching process, such as laser etching, plasma etching, or wet etching, to pattern the surface of the substrate 10. This allows for the construction of a high-precision closed or semi-closed venting path structure without altering the overall thickness or conductive path of the substrate 10. In this structure, after gas enters from the inner groove, it sequentially passes through multiple circumferentially arranged openings and bends, ultimately being guided to the second through-hole 102 leading to the outside, thus forming a labyrinthine spiral venting channel 11. This structure, while achieving self-balancing of gas pressure, also significantly enhances the shielding capability against external particles and increases the acoustic dissipation of the sound wave propagation path, effectively improving the dustproof and acoustic isolation performance of the packaging system.
[0041] In some embodiments, the first through-hole 101 and the second through-hole 102 are located at opposite ends of the venting channel 11. By placing the first through-hole 101 and the second through-hole 102 at opposite ends of the venting channel 11, gas exchange between the inside and outside of the sensor package structure 100 must pass through the entire venting channel 11 path. This effectively utilizes the structural design within the venting channel 11 to guide, filter, and control the airflow. Furthermore, the arrangement of the through-holes at both ends also facilitates the integrated design and processing control of the venting channel 11, improving overall packaging process compatibility and product reliability.
[0042] Furthermore, the substrate 10 has a first side 12 and a second side 13 arranged opposite to each other, with a first through hole 101 disposed near the first side 12 and a second through hole 102 disposed near the second side 13. By disposing the first through hole 101 and the second through hole 102 near the first side 12 and the second side 13 of the substrate 10, respectively, the lateral extension length of the venting channel 11 within the substrate 10 can be significantly extended, thereby increasing the total length of the venting path.
[0043] It is understood that the venting pipe has a cross-sectional area in its axial extension direction, and the cross-sectional area is circular. Preferably, the cross-section is circular or approximately circular, so that the venting channel 11 can be regarded as a cylindrical pipe. This venting channel 11 structure not only enables gas conduction between the encapsulation cavity 1001 and the outside world, but also constitutes a physical impedance path for the propagation of external sound waves.
[0044] In acoustic modeling, the acoustic impedance Z of a cylindrical gas channel can be approximately estimated using the following formula:
[0045] Where μ is the hydrodynamic viscosity, l is the pipe length, Δl is the corrected length at the end of the venting channel 11, ω = 2πf, f is the sound frequency, ρ is the gas density, and r is the radius of the venting channel 11. This calculation model shows that the equivalent acoustic impedance of the venting channel 11 is controlled by its cross-sectional area (i.e., r squared) and the channel length l. Therefore, in the design stage of the sensor packaging structure 100, according to the specific acoustic isolation requirements, combined with the above formula, the sound wave attenuation capability of the venting channel 11 can be quantitatively designed by setting the size parameters (such as the channel diameter and length) to achieve the desired acoustic shielding effect.
[0046] It is understood that the package cavity 1001 houses a MEMS chip 40 and an ASIC chip 50. The MEMS chip 40 is used to sense external physical signals, such as sound waves or pressure signals, while the ASIC chip 50 is used to process, amplify, convert, or encode the signals output by the MEMS chip 40. By integrating the MEMS chip 40 and the ASIC chip 50 into the same package cavity 1001, the signal path can be effectively shortened, and the anti-interference capability and response speed can be improved. This is suitable for high-precision, low-noise audio pickup scenarios, such as audio acquisition in mobile phones, headphones, and voice recognition devices.
[0047] It is understood that the sensor packaging structure 100 also includes a connecting structure 30, through which the substrate 10 and the housing 20 are connected to form a sealed packaging cavity 1001. The connecting structure 30 can be solder or adhesive, etc. The connecting structure 30 enables stable assembly and hermetic sealing between the substrate 10 and the housing 20, ensuring the integrity of the packaging cavity 1001 and improving packaging strength and environmental adaptability.
[0048] It is understood that the sensor package structure 100 is a microphone. Specifically, the package cavity 1001 houses a MEMS microphone chip and / or a matching ASIC signal processing chip. The MEMS chip 40 senses external sound wave signals and converts them into electrical signals, while the ASIC chip 50 performs amplification, filtering, analog-to-digital conversion, or noise suppression on the electrical signals. The microphone typically includes a sound-sensitive unit for pickup. The venting channel 11 in the package structure is designed to achieve pressure balance and effectively suppress direct interference from external sounds, providing a certain acoustic impedance to ensure consistent frequency response and signal-to-noise ratio performance. This microphone structure is suitable for applications with high acoustic performance requirements, such as voice recognition, communication equipment, audio acquisition, noise-canceling headphones, and smart terminals.
[0049] This embodiment also provides an electronic device, including a housing and the aforementioned sensor packaging structure 100 disposed within the housing. Since the electronic device incorporates all the technical solutions of all embodiments of the aforementioned sensor packaging structure 100, it possesses at least all the beneficial effects brought by all the aforementioned technical solutions, which will not be elaborated upon here. The aforementioned electronic device can be a portable or wearable device, such as a smartphone, smartwatch, smart bracelet, or iPad.
[0050] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.
Claims
1. A sensor packaging structure, characterized in that, include: A substrate, wherein the substrate is provided with a first through hole and a second through hole; An outer casing, which covers the substrate and encloses it to form an encapsulation cavity; A venting channel is formed within the substrate. The venting channel is connected to the packaging cavity through the first through hole and to the outside through the second through hole. The portion of the venting channel located between the first through hole and the second through hole has at least two bends.
2. The sensor packaging structure according to claim 1, characterized in that, The substrate is provided with a first shielding part and a second shielding part, which are located in the venting channel and are interlocked with each other to form at least two bending structures.
3. The sensor packaging structure according to claim 2, characterized in that, The first blocking portion includes a plurality of first strip-shaped protrusions, and the second blocking portion includes a plurality of second strip-shaped protrusions. The plurality of first strip-shaped protrusions and the plurality of second strip-shaped protrusions are alternately arranged in sequence along a first direction and interlock with each other to form the bending structure. The first direction is the direction from the first through hole to the second through hole.
4. The sensor packaging structure according to claim 1, characterized in that, The substrate is provided with a plurality of arc-shaped grooves, which are arranged in a concentric circle along the radial direction of the concentric circle. Two adjacent arc-shaped grooves in the radial direction are connected by an opening, so that the plurality of arc-shaped grooves form the bending structure.
5. The sensor packaging structure according to claim 4, characterized in that, Two adjacent openings along the radial direction have an included angle between them along the circumferential direction of the concentric circles, the included angle being greater than 0° and less than 180°.
6. The sensor packaging structure according to claim 1, characterized in that, The substrate has a first side and a second side arranged opposite to each other, with the first through hole disposed near the first side and the second through hole disposed near the second side.
7. The sensor packaging structure according to any one of claims 1 to 6, characterized in that, The encapsulation cavity contains a MEMS chip and an ASIC chip.
8. The sensor packaging structure according to any one of claims 1 to 6, characterized in that, The sensor packaging structure also includes a connection structure, through which the substrate and the housing are connected.
9. The sensor packaging structure according to claim 1, characterized in that, The venting channel has a cross-section perpendicular to its own extending direction, and the cross-section is circular.
10. An electronic device, characterized in that, Includes the sensor packaging structure according to any one of claims 1 to 9.