A MEMS microphone

Abstract

The application provides a MEMS microphone, comprising a substrate, a MEMS chip, an ASIC chip and a transfer island arranged on the substrate; the MEMS chip and the ASIC chip are connected through the transfer island; the transfer island is used for forwarding a pressure signal output by the MEMS chip to the ASIC chip; and the ASIC chip is used for converting the pressure signal output by the MEMS chip into a voltage signal. Compared with the prior art, the MEMS microphone of the application connects the MEMS chip and the ASIC chip through the transfer island, thereby avoiding the connection of gold wires, reducing the exposure time of the MEMS chip in a high-risk environment, and reducing the influence of environmental foreign matters on the MEMS microphone.

Description

Technical Field

[0001] This application relates to the field of acoustic technology, specifically to a MEMS microphone. Background Technology

[0002] MEMS microphones are miniature microphones based on microelectromechanical systems (MEMS) technology. They have advantages such as small size, low power consumption, and low cost, and have a wide range of applications in various fields, such as smartphones, wearable devices, in-vehicle voice interaction systems, medical devices, industrial equipment monitoring, security and surveillance.

[0003] MEMS microphones utilize MEMS chips, and foreign matter buildup on the diaphragm of these chips is a core issue in the MEMS industry. Its impact on MEMS products is uncertain; compositional analysis shows that 60%-80% of foreign matter originates from the workshop environment. This is likely because MEMS chips are mostly connected to other chips via gold wire bonding, which exposes the chips to the workshop environment for extended periods, increasing the risk of foreign matter contamination. Despite multiple improvements to the workshop aimed at reducing turnaround time, there has been no significant improvement.

[0004] Therefore, how to reduce the impact of environmental foreign objects on MEMS microphones is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this application is to provide a MEMS microphone that can reduce the impact of environmental foreign objects on the MEMS microphone.

[0006] This application provides a MEMS microphone, including:

[0007] A substrate and a MEMS chip, an ASIC chip, and a transition island disposed on the substrate;

[0008] The MEMS chip and the ASIC chip are connected via the adapter island;

[0009] The transfer island is used to forward the pressure signal output by the MEMS chip to the ASIC chip;

[0010] The ASIC chip is used to convert the pressure signal output by the MEMS chip into a voltage signal.

[0011] In one possible implementation, the adapter island is soldered to the ASIC chip via a ball grid array or bonded with non-conductive adhesive.

[0012] In one possible implementation, the adapter island is welded to the MEMS chip via a ball grid array or bonded with non-conductive adhesive.

[0013] In one possible implementation, the substrate has acoustic holes, and a waterproof and breathable membrane is disposed within the acoustic holes.

[0014] In one possible implementation, the MEMS chip has a diaphragm.

[0015] In one possible implementation, the MEMS microphone further includes:

[0016] A housing is disposed on the substrate, and the housing and the substrate form a cavity, wherein the MEMS chip, the ASIC chip and the adapter island are respectively located in the cavity.

[0017] In one possible implementation, the housing is a metal shell.

[0018] In one possible implementation, the substrate is a PCB board.

[0019] The MEMS microphone provided in this application includes: a substrate and a MEMS chip, an ASIC chip, and an adapter island disposed on the substrate; the MEMS chip and the ASIC chip are connected through the adapter island; the adapter island is used to forward the pressure signal output by the MEMS chip to the ASIC chip; the ASIC chip is used to convert the pressure signal output by the MEMS chip into a voltage signal. Compared with the prior art, the MEMS microphone of this application allows for quick connection of the MEMS chip and ASIC chip through the adapter island, thereby eliminating the need for gold wire bonding, reducing the exposure time of the MEMS chip in high-risk environments, and thus reducing the impact of environmental foreign objects on the MEMS microphone. 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 this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0021] Figure 1 A circuit diagram of a MEMS microphone provided by some embodiments of this application is shown;

[0022] Figure 2 This paper shows a schematic diagram of the structure of a MEMS chip and an ASIC chip connected by an adapter island according to some embodiments of this application;

[0023] Explanation of reference numerals in the attached figures:

[0024] Substrate 10, MEMS chip 20, ASIC chip 30, and adapter island 40. Detailed Implementation

[0025] 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.

[0026] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text is to include three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0028] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains.

[0029] ASIC is an abbreviation for Application-Specific Integrated Circuit, a type of dedicated chip designed specifically for a particular need. Examples include dedicated audio and video processors, and many dedicated AI chips can also be considered a type of ASIC. The characteristics of ASICs are their focus on specific user needs. Compared to general-purpose integrated circuits, ASICs offer advantages in mass production, such as smaller size, lower power consumption, improved reliability, higher performance, enhanced security, and lower cost.

[0030] MEMS (Micro-Electro-Mechanical Systems) chips are a technology that integrates micro-mechanical components, sensors, actuators, and electronic components onto a single microchip. MEMS chips are widely used in smart devices, healthcare, automotive electronics, aerospace, and other fields, characterized by their small size, light weight, low power consumption, and wide range of applications. MEMS sensors are a crucial component of MEMS chips, primarily used for detecting various environmental or biological signals, such as temperature, pressure, and acceleration, as well as analyzing fluids and gases. MEMS sensors convert the measured physical signals into electrical signals through miniaturized mechanical structures. For example, an acceleration MEMS sensor can measure acceleration by using a miniature cantilever beam that displaces under acceleration, and then converting this physical displacement into an electrical signal through changes in capacitance or resistance. This miniaturization and integration feature makes MEMS sensors widely used in smartphones, wearable devices, and automotive safety systems.

[0031] Please refer to Figure 1 It illustrates a circuit diagram of a MEMS microphone provided by some embodiments of this application, such as... Figure 1 As shown, the MEMS microphone includes: a substrate 10 and a MEMS chip 20, an ASIC chip 30 and an adapter island 40 disposed on the substrate 10.

[0032] Specifically, the substrate 10 can be a PCB board, or other types of substrates, and this application does not limit it.

[0033] The MEMS chip 20 and the ASIC chip 30 are connected via the adapter island 40. In the MEMS microphone, the MEMS chip 20 converts sound into changes in capacitance and resistance signals, while the ASIC chip 30 converts these changes into electrical signals. The adapter island 40 can forward the pressure signal output by the MEMS chip 20 to the ASIC chip 30.

[0034] Specifically, the adapter island 40 and the ASIC chip 30 can be bonded together using a ball grid array or non-conductive adhesive. The adapter island 40 and the MEMS chip 20 can also be bonded together using a ball grid array or non-conductive adhesive. Figure 2 The diagram shows the structure of the MEMS chip and the ASIC chip connected by an adapter island.

[0035] In the integrated packaging of ASIC chips and MEMS chips, the adapter island 40 serves as a key intermediary layer, and its connection method directly affects the mechanical stability, electrical performance, and reliability of the module.

[0036] Ball Grid Array (BGA) bonding is a microsphere flip-chip bonding technology that uses microspheres to achieve vertical interconnection between the chip and the interface island. Solder balls are placed on the pads of the interface island, and the ASIC / MEMS is flip-chip bonded to the surface of the interface island via reflow soldering, forming a vertical electrical signal path. Using microspheres instead of traditional gold wire bonding shortens the signal path and improves high-frequency performance. After bonding, epoxy resin is injected into the gap between the chip and the interface island, and then cured by baking to disperse mechanical stress and prevent fatigue fracture of the microspheres.

[0037] Non-conductive adhesive is a type of glue that does not conduct electricity. It can be used as an adhesive material to fix IC packages onto circuit boards, providing a reliable mechanical connection without affecting electrical performance. ASICs / MEMS can be electrically connected to the adapter island and then bonded using non-conductive adhesive.

[0038] Specifically, the working principle of the MEMS microphone mentioned in this application is as follows:

[0039] The MEMS chip 20 has a diaphragm that converts sound wave vibrations into pressure signals. The adapter island 40 forwards the pressure signal output from the MEMS chip 20 to the ASIC chip 30, which then converts the pressure signal into a voltage signal for output. Therefore, in this application, the MEMS chip and ASIC chip are connected via the adapter island, eliminating the need for wire bonding. This reduces the exposure time of the MEMS chip's diaphragm in high-risk environments, lowers the proportion of foreign matter in the membrane, and thus reduces the impact of environmental foreign matter on the MEMS diaphragm, minimizing potential instability during MEMS chip operation. The adapter island also shortens the signal path and reduces latency, thereby improving the performance of the MEMS microphone.

[0040] In some embodiments, the MEMS microphone further includes:

[0041] A housing is disposed on the substrate 10, and the housing and the substrate 10 form a cavity, in which the MEMS chip 20, ASIC chip 30, and adapter island 40 are respectively located. Specifically, the housing is a metal shell. The shell can protect the various components therein and can also be used for electromagnetic shielding.

[0042] In some embodiments, the substrate 10 has acoustic holes, and a waterproof and breathable membrane is disposed within the acoustic holes. The waterproof and breathable membrane is a waterproof membrane with a microporous structure on its surface, which can achieve a waterproof effect while ensuring breathability. Because a waterproof and breathable membrane is disposed on the acoustic holes leading to the outside, the MEMS microphone provided in this application also has a waterproof function.

[0043] The MEMS microphone provided in this embodiment includes: a substrate and a MEMS chip, an ASIC chip, and an adapter island disposed on the substrate; the MEMS chip and the ASIC chip are connected through the adapter island; the adapter island is used to forward the pressure signal output by the MEMS chip to the ASIC chip; the ASIC chip is used to convert the pressure signal output by the MEMS chip into a voltage signal. Compared with the prior art, the MEMS microphone of this application allows the MEMS chip and ASIC chip to be quickly connected through the adapter island, thereby eliminating the need for gold wire bonding, reducing the exposure time of the MEMS chip in high-risk environments, and thus reducing the impact of environmental foreign objects on the MEMS microphone.

[0044] It should be noted that:

[0045] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0046] Similarly, it should be understood that, for the purpose of simplification and aiding understanding of one or more aspects of the application, various features of the application have sometimes been grouped together in a single embodiment, figure, or description thereof in the above description of exemplary embodiments of the application. However, this approach of disclosure should not be construed as reflecting an intention that the claimed application requires more features than expressly recited in each claim. Rather, as reflected in the following claims, the application aspect comprises fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the application.

[0047] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0048] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0049] It should be noted that the above embodiments are illustrative of this application and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0050] The above description is merely a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A MEMS microphone, characterized in that, include: A substrate and a MEMS chip, an ASIC chip, and a transition island disposed on the substrate; The MEMS chip and the ASIC chip are connected via the adapter island; The transfer island is used to forward the pressure signal output by the MEMS chip to the ASIC chip; The ASIC chip is used to convert the pressure signal output by the MEMS chip into a voltage signal.

2. The MEMS microphone according to claim 1, characterized in that, The adapter island is bonded to the ASIC chip via ball grid array welding or non-conductive adhesive bonding.

3. The MEMS microphone according to claim 1 or 2, characterized in that, The adapter island is bonded to the MEMS chip via ball grid array welding or non-conductive adhesive bonding.

4. The MEMS microphone according to claim 1, characterized in that, The substrate has acoustic holes, and a waterproof and breathable membrane is disposed inside the acoustic holes.

5. The MEMS microphone according to claim 1, characterized in that, The MEMS chip has a diaphragm.

6. The MEMS microphone according to claim 1, characterized in that, The MEMS microphone also includes: A housing is disposed on the substrate, and the housing and the substrate form a cavity, wherein the MEMS chip, the ASIC chip and the adapter island are respectively located in the cavity.

7. The MEMS microphone according to claim 6, characterized in that, The casing is a metal casing.

8. The MEMS microphone according to claim 1, characterized in that, The substrate is a PCB board.

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