CN211702389U

CN211702389U - MEMS microphone and electronic product

Info

Publication number: CN211702389U
Application number: CN202020401713.XU
Authority: CN
Inventors: 张瑞霞
Original assignee: Goertek Microelectronics Inc
Current assignee: Goertek Microelectronics Inc
Priority date: 2020-03-25
Filing date: 2020-03-25
Publication date: 2020-10-16
Anticipated expiration: 2030-03-25

Abstract

The utility model relates to a MEMS microphone and electronic product, which comprises a combined substrate, an MEMS chip and a waterproof membrane arranged in an accommodating cavity; the combined substrate comprises a first substrate and a second substrate which are arranged in a stacked mode, an accommodating cavity is formed between the first substrate and the second substrate, a first sound hole communicated to the accommodating cavity is formed in the first substrate, and a second sound hole communicated to the accommodating cavity is formed in the second substrate; the MEMS chip is arranged on the combined substrate; the waterproof membrane separates the first acoustic aperture from the second acoustic aperture. The utility model provides a MEMS microphone and electronic product, in the foreign matters such as dust, liquid in the waterproof membrane effectively prevented the outside environment got into the MEMS microphone, improved the reliability of MEMS microphone.

Description

MEMS microphone and electronic product

Technical Field

The utility model relates to a micro-electro-mechanical system field, concretely relates to MEMS microphone and electronic product.

Background

A Micro-Electro-Mechanical System (MEMS) microphone is an acoustoelectric transducer manufactured based on the MEMS technology, has the characteristics of small volume, good frequency response, low noise and the like, and is one of essential devices of a mobile terminal. Generally, a MEMS microphone product includes a MEMS chip based on capacitance detection and an Application Specific Integrated Circuit (ASIC) chip, where the capacitance of the MEMS chip changes correspondingly with the change of an incoming sound, and the ASIC chip processes and outputs a changed capacitance signal to pick up the sound.

In recent years, the related technologies of electronic products have been developed rapidly, and the performance requirements of electronic products are higher and higher, so as to meet the application requirements and reliability requirements of electronic products in different environments. The current MEMS microphone needs to directly receive external sound, so the MEMS chip is directly connected to the external environment through the microphone sound hole. This design results in a strong tendency for dust, liquid, etc. in the outside environment to enter the MEMS microphone from the microphone sound hole, thereby affecting the acoustic performance of the MEMS microphone. MEMS microphones suffer from water ingress failure and have limited reliability.

SUMMERY OF THE UTILITY MODEL

It is an object of the present invention to provide an improved MEMS microphone and electronic product.

According to an aspect of the present invention, there is provided a MEMS microphone, including:

the combined substrate comprises a first substrate and a second substrate which are arranged in a stacked mode, an accommodating cavity is formed between the first substrate and the second substrate, a first sound hole communicated to the accommodating cavity is formed in the first substrate, and a second sound hole communicated to the accommodating cavity is formed in the second substrate;

a MEMS chip disposed on the combination substrate;

a waterproof membrane disposed in the receiving cavity, an edge of the waterproof membrane being fixed in the receiving cavity, the waterproof membrane separating the first acoustic aperture from the second acoustic aperture.

Optionally, the MEMS microphone further includes a package cover, the package cover is disposed on the combined substrate, the package cover and the combined substrate form a back cavity, and the MEMS chip is located in the back cavity.

Optionally, a sinking groove is formed on a surface of one side of the first substrate, which is close to the second substrate, and the sinking groove and the second substrate enclose to form the accommodating cavity;

or a sinking groove is formed on the surface of one side, close to the first substrate, of the second substrate, and the sinking groove and the first substrate enclose to form the accommodating cavity.

Optionally, a corresponding and consistent heavy groove is formed on one side surface of the first substrate close to the second substrate and on one side surface of the second substrate close to the first substrate, and the heavy grooves are buckled to form the accommodating cavity.

Optionally, the shape of the waterproofing membrane matches the shape of the sink.

Optionally, the depth of the sinking groove is less than half of the thickness of the first substrate and/or the second substrate on which the sinking groove is formed.

Optionally, the edge of the waterproof membrane is fixed on the bottom surface of the accommodating cavity in an adhesion mode.

Optionally, a first gap is formed between the central region of the waterproof membrane and the first substrate;

and/or a second gap is formed between the central area of the waterproof membrane and the second substrate.

Optionally, the first acoustic hole is formed by a plurality of holes distributed on the first substrate;

and/or the presence of a gas in the gas,

the second sound hole is composed of a plurality of holes distributed on the second substrate.

Optionally, the first substrate and the second substrate are soldered to form an electrical connection.

According to the utility model discloses a second aspect provides an electronic product, include: a product body and the above-mentioned MEMS microphone, the MEMS microphone being disposed in the product body, the MEMS microphone being configured for receiving sound for conversion into a sound signal.

Technical scheme's beneficial effect lies in: foreign matters such as dust and liquid in the outside environment are effectively prevented from entering the MEMS microphone through the waterproof membrane, and the reliability of the MEMS microphone is improved.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the invention, which proceeds with reference to the accompanying drawings.

Drawings

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

Fig. 1 is a schematic structural diagram of a MEMS microphone according to an embodiment of the present invention;

fig. 2 is a reference diagram of a usage state of a MEMS microphone according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a MEMS microphone according to another embodiment of the present invention;

fig. 4 is a reference diagram of a usage state of a MEMS microphone according to another embodiment of the present invention.

In the figure: 1. assembling a substrate; 11. a first substrate; 111. a first sound hole; 12. a second substrate; 121. a second sound hole; 13. an accommodating chamber; 2. an MEMS chip; 3. a water-resistant film; 41. a first gap; 42. a second gap; 5. an ASIC chip.

Detailed Description

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

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

As shown in fig. 1 to 4, the present embodiment provides a MEMS microphone including a combination substrate 1, a MEMS chip 2, and a waterproof membrane 3. The combined substrate 1 is a circuit board and is used for realizing electrical connection between related components in the MEMS microphone.

Specifically, the composite substrate 1 includes a first substrate 11 and a second substrate 12 which are stacked. Preferably, the second substrate 12 is stacked on the upper surface of the first substrate 11, and the bottom periphery of the second substrate 12 is fixed on the first substrate 11, so as to stably fix the second substrate 12 on the first substrate 11, thereby facilitating the provision of a sink in the middle of the first substrate 11 and/or the second substrate 12.

An accommodating chamber 13 is formed between the first substrate 11 and the second substrate 12, and the accommodating chamber 13 serves as an accommodating space for the waterproof film 3 for disposing the waterproof film 3. A first sound hole 111 communicated to the accommodating cavity 13 is formed on the first substrate 11, and sound in the outside environment enters the accommodating cavity 13 through the first sound hole 111; a second sound hole 121 communicating to the accommodating chamber 13 is formed in the second substrate 12, and sound in the accommodating chamber 13 enters the inside of the MEMS microphone through the second sound hole 121. The first sound hole 111 and the second sound hole 121 each function to facilitate the passage of sound. As shown in fig. 1, the first sound hole 111 penetrates from the bottom surface of the housing chamber 13 to the bottom surface of the first substrate 11, and the first sound hole 111 communicates between the top surface and the bottom surface of the first substrate 11 through the housing chamber 13. Similarly, the second sound hole 121 penetrates from the top surface of the accommodating chamber 13 to the top surface of the second substrate 12, and the second sound hole 121 communicates between the top surface and the bottom surface of the second substrate 12 through the accommodating chamber 13. In the case where the waterproof film 3 is not provided, the first sound hole 111, the second sound hole 121, and the housing chamber 13 communicate with each other.

In the present embodiment, the housing chamber 13 is formed in various ways. In a specific embodiment, as shown in fig. 3 and 4, a sunken groove is formed on a surface of the first substrate 11 near the second substrate 12, that is, a middle portion of the surface of the first substrate 11 near the second substrate 12 is recessed to a certain depth in a direction away from the second substrate 12, so that the sunken groove is formed in the first substrate 11. The open end of the sinking groove is closed by the second substrate 12, so that the sinking groove and the second substrate 12 enclose to form an accommodating cavity 13. The first substrate 11 is provided with the sinking groove, the waterproof membrane 3 is arranged in the sinking groove of the first substrate 11, the operation process can be carried out simultaneously with the operation of assembling the MEMS chip 2 on the second substrate 12, the assembling time of the MEMS microphone is greatly shortened, and finally, the second substrate 12 is fixed on the first substrate 11, so that the assembling efficiency of the MEMS microphone is improved.

In an alternative embodiment, as shown in fig. 1 and 2, a sink is formed on a surface of the second substrate 12 near the first substrate 11. That is, the middle portion of the surface of the second substrate 12 close to the first substrate 11 is recessed to a certain depth in a direction away from the first substrate 11, so that a sink is formed in the second substrate 12. The open end of the sinking groove is closed by the first substrate 11, so that the sinking groove and the first substrate 11 enclose to form an accommodating cavity 13. Providing the sinking groove in second substrate 12 and second sound hole 121 communicating with the sinking groove helps to reduce the depth of second sound hole 121 on second substrate 12, thereby well reducing the acoustic resistance of sound when propagating in second sound hole 121 and helping sound propagate in second sound hole 121.

In another alternative embodiment, a sunken groove is formed on a side surface of the first substrate 11 close to the second substrate 12, a sunken groove is also formed on a side surface of the second substrate 12 close to the first substrate 11, the two sunken grooves have the same size and correspond to each other in position, open ends of the two sunken grooves are opposite and are buckled to form the accommodating cavity 13, so that the two sunken grooves are buckled to form the accommodating cavity 13 with a regular shape, and the waterproof membrane 3 is quickly arranged in the accommodating cavity 13 at an accurate position. First base plate 11 and second base plate 12 all are provided with heavy groove, form one by two heavy grooves and hold chamber 13, and under the same condition of size in holding chamber 13, the needs that can satisfy the assembly of first base plate 11 and second base plate 12 that have less thickness simultaneously. Preferably, the first substrate 11 and the second substrate 12 have the same thickness, which facilitates industrial production of the first substrate 11 and the second substrate 12 and improves production efficiency.

In the present embodiment, the MEMS chip 2 is disposed on the combined substrate 1, the MEMS chip 2 corresponds to the second sound hole 121, and the second sound hole 121 communicates with the inner cavity of the MEMS chip 2. The MEMS chip 2 senses sound pressure entering the inner cavity of the MEMS chip 2 through the second sound hole 121 and converts the sound pressure into an electrical signal.

Optionally, the MEMS microphone further includes an ASIC chip 5, and the ASIC chip 5 is disposed on the combination substrate 1. The MEMS chip 2 may be connected to the ASIC chip 5 by a wire, the MEMS chip 2 may also be electrically connected to the ASIC chip 5 through the first substrate 11, and the ASIC chip 5 is electrically connected to the second substrate 12 through the first substrate 11. The capacitance of the MEMS chip 2 changes correspondingly with the difference of the input sound signal, and then the ASIC chip 5 is used to process the changed capacitance signal and output the processed capacitance signal to the combination substrate 1, thereby realizing the sound pickup.

As shown in fig. 1, the waterproof film 3 is disposed in the accommodating chamber 13, the edge of the waterproof film 3 is fixed in the accommodating chamber 13, and the waterproof film 3 separates the first sound hole 111 from the second sound hole 121. By providing the waterproof film 3, the portion communicating with the inside of the MEMS microphone through the second sound hole 121 is protected by the waterproof film 3, and foreign matter entering from the first hole is blocked by the waterproof film 3 and is difficult to enter the second sound hole 121, thereby improving the reliability of the MEMS microphone.

The working principle of the MEMS microphone is as follows: the sound sequentially passes through the first sound hole 111, the waterproof membrane 3, and the second sound hole 121, and then enters the inner cavity of the MEMS chip 2, and the MEMS chip 2 senses the sound pressure and converts the sound pressure into an electrical signal.

In the present embodiment, the waterproof film 3 is used to block dust, liquid, and the like in the external environment from entering the second sound hole 121 from the first sound hole 111, and thus effectively prevent dust, liquid, and the like in the external environment from entering the inner cavity of the MEMS chip 2. This helps to keep the MEMS chip 2 having a clean and tidy cavity environment, thereby ensuring that the MEMS chip 2 can quickly and accurately sense the sound pressure and convert the sound pressure into an electrical signal. Meanwhile, when strong airflow enters from the first sound hole 111, the waterproof membrane 3 can intercept impact force brought to the MEMS chip 2 by the strong airflow, so that the MEMS chip 2 is prevented from being impacted by the strong airflow, the stability of converting sound pressure into an electric signal by the MEMS chip 2 is ensured, and the stability and the reliability of the MEMS microphone in the using process are ensured.

The technical scheme of the utility model hold chamber 13 in order to hold waterproofing membrane 3 through offering on combination substrate 1. On one hand, the occupied space is small, and the influence on the overall appearance of the MEMS microphone is small. And, the waterproof membrane 3 is directly arranged in the accommodating cavity 13 of the combined substrate 1, and the processing technology is simple. On the other hand, the waterproof film 3 can be protected by the buildup substrate 1, reducing the risk of damage. Particularly, the waterproof membrane 3 does not occupy the internal volume of the MEMS microphone additionally, and meets the requirement of the internal structure of the MEMS microphone to be compact. In practical application, the MEMS microphone can meet the requirement of products with limited space where the MEMS chip 2 is located, and the MEMS microphone with good waterproof and dustproof performances is provided for the products.

The utility model discloses a water proof membrane 3 can be through sealed fixed connection form, keeps apart first sound hole 111 and second sound hole 121 completely, also can adopt unsealed fixed connection form, leaves the gap that supplies sound to pass, reduces the acoustic resistance.

The material of the waterproofing membrane 3 itself may take at least two different forms. In the first form, the waterproof membrane 3 has high density and good isolation and waterproof performance, and airflow is difficult to directly pass through. The waterproof membrane 3 can adopt a sealed fixed connection mode, sound waves transmitted from the first sound hole 111 generate pressure on the waterproof membrane 3, the waterproof membrane 3 vibrates, and sound vibration is transmitted to the MEMS chip 2 through the second sound hole 121, so that sound transmission is realized. In the second form, the waterproofing membrane 3 is relatively low in density and has a certain waterproofing property while allowing airflow to pass therethrough. The sound waves transmitted from the first sound hole 111 can be directly transmitted to the second sound hole 121 and the MEMS chip 2 through the waterproof film 3, so that sound transmission is realized.

In the present embodiment, when the first substrate 11 is provided with the sinking groove, the waterproof film 3 is provided in the sinking groove of the first substrate 11; when the second substrate 12 is provided with the sink, the waterproofing membrane 3 is directly provided on the surface of the first substrate 11 as the bottom surface of the accommodating chamber 13. Therefore, the waterproof films 3 are each provided on the first substrate 11, which can be performed simultaneously with the operation of laying the MEMS chip 2 and the ASIC chip 5 on the second substrate 12, thereby greatly improving the assembly efficiency of the MEMS microphone. In addition, the MEMS microphone in this embodiment has a surface circuit of the circuit board on which the MEMS chip 2 and the ASIC chip 5 are disposed, and has versatility and a wider application range.

Optionally, the MEMS microphone further includes a package cover, the package cover is disposed on the combined substrate 1, the package cover and the combined substrate 1 form a back cavity, and the MEMS chip 2 is located in the back cavity. The packaging shell not only can better protect the MEMS chip 2, but also is convenient for the MEMS chip 2 to accurately sense sound pressure in a closed back cavity and stably convert the sound pressure into an electric signal. The back cavity structure is designed for the MEMS microphone, so that the acoustic performance of the microphone can be effectively improved.

The waterproof membrane 3 in this embodiment is disposed in the accommodating cavity 13 of the combined substrate 1, and does not occupy the volume of the back cavity of the MEMS microphone, thereby meeting the requirement of a product with a small size of the back cavity where the MEMS chip 2 is located.

In addition, the composite substrate 1 may be provided with a larger accommodating chamber 13 to accommodate a larger area of the waterproof membrane 3. The larger the area of the waterproof membrane 3 is, the less the sound vibration is hindered from propagating from the first sound hole 111 to the second sound hole 121, so that sound can better penetrate through the waterproof membrane 3 and pass through the inner cavity of the MEMS chip 2 of the second sound hole 121, and the sound loss is small. Therefore, the waterproof membrane 3 with a relatively large area can also comprehensively improve the acoustic performance of the MEMS microphone, thereby ensuring that the MEMS microphone has a low distortion rate and a good acoustic effect.

In an alternative embodiment, the waterproof membrane 3 occupies a larger area in the accommodating cavity 13, and the membrane material thereof may be a material with better isolation performance. Thus, the foreign matter is hard to pass through the waterproof membrane 3. On the other hand, because the waterproof membrane 3 has a large area, when receiving sound vibration, the sensitivity of self-generated vibration is high, and the sound transmitted from the first sound hole 111 can be better reduced, so that the vibration is transmitted to the MEMS chip 2. The distortion degree of the MEMS microphone is reduced, and meanwhile, the waterproof performance is guaranteed.

Optionally, the shape of the waterproofing membrane 3 matches the shape of the sink. The shape of the waterproofing membrane 3 is matched according to the shape of the sink, so that the waterproofing membrane 3 fixed in the sink has a large area. The waterproof membrane 3 with a relatively large area can also comprehensively improve the acoustic performance of the MEMS microphone, thereby ensuring that the MEMS microphone has a lower distortion rate and a better acoustic effect.

Optionally, when the sinking groove is disposed in the first substrate 11, the depth of the sinking groove is less than half of the thickness of the first substrate 11 formed by the sinking groove, which not only enables the position of the first substrate 11 corresponding to the sinking groove to have a certain thickness, thereby ensuring that the first substrate 11 has sufficient mechanical strength, but also ensures that the first sound hole 111 has a certain depth, so as to better block foreign matters from entering the sinking groove through the first sound hole 111, thereby improving the reliability of the MEMS microphone in preventing the foreign matters from entering the interior thereof. When the sinking groove is arranged in the second substrate 12, the depth of the sinking groove is less than half of the thickness of the second substrate 12 formed by the sinking groove, so that the position of the second substrate 12 corresponding to the sinking groove has a certain thickness, and the second substrate 12 has better mechanical strength; when the first substrate 11 and the second substrate 12 are both provided with the sinking grooves, the depth of the sinking grooves is less than half of the thickness of the first substrate 11 and the second substrate 12, so that the positions of the first substrate 11 and the second substrate 12 corresponding to the sinking grooves are both provided with proper thickness, and the first substrate 11 and the second substrate 12 are both guaranteed to have good mechanical strength.

Optionally, the edge of the waterproof membrane 3 is adhesively fixed on the bottom surface of the accommodating cavity 13, the bottom surface of the accommodating cavity 13 is located on the first substrate 11, and the adhesion improves the stability of the waterproof membrane 3 fixed on the first substrate 11. The edge of the waterproof film 3 is adhesively fixed to the first substrate 11, so that a sealing connection is achieved, and the waterproof film 3 is adhesively connected to the bottom surface of the accommodating cavity 13 in a ring-shaped sealing manner, so that the first sound hole 111 is completely separated from the second sound hole 121. The waterproof membrane 3 can better play a role in filtration and isolation.

Optionally, a first gap 41 is formed between the central region of the waterproofing membrane 3 and the first substrate 11. The edge of the waterproof membrane 3 is fixed on the first substrate 11, and a first gap 41 is formed between the central area of the waterproof membrane 3 and the first substrate 11, so that the waterproof membrane 3 can vibrate in the first gap 41 when receiving sound vibration, the sensitivity of vibration generated along with the waterproof membrane is high, and sound transmitted from the first sound hole 111 can be well reduced.

Optionally, a second gap 42 is formed between the central region of the waterproof membrane 3 and the second substrate 12, and the waterproof membrane 3 can vibrate in the second gap 42 when receiving sound vibration, so that the sensitivity of vibration generated by the waterproof membrane 3 is high, and sound transmitted from the first sound hole 111 can be better reduced.

In an alternative embodiment, a first gap 41 is formed between the central region of the waterproof membrane 3 and the first substrate 11, and a second gap 42 is formed between the central region of the waterproof membrane 3 and the second substrate 12, so that the waterproof membrane 3 can vibrate in the first gap 41 and the second gap 42 when receiving sound vibration, the sensitivity of the waterproof membrane 3 vibrating along with the sound vibration is high, sound transmitted from the first sound hole 111 can be well restored, and then the vibration is transmitted to the MEMS chip 2. The distortion degree of the MEMS microphone is reduced, and meanwhile, the waterproof performance is guaranteed.

In another optional embodiment, the first sound hole 111 corresponds to the second sound hole 121, which is helpful for sound to directly enter the second sound hole 121 from the first sound hole 111 through the waterproof film 3, reduces the propagation distance of sound, and reduces the resistance of sound vibration in the propagation process from the first sound hole 111 to the second sound hole 121, so that the second sound hole 121 can better reduce the sound transmitted from the first sound hole 111, and then transmits the vibration to the MEMS chip 2, thereby reducing the distortion of sound of the MEMS microphone, and improving the acoustic effect of the MEMS microphone.

Alternatively, the first acoustic hole 111 is composed of a plurality of holes distributed on the first substrate 11. That is, the first sound hole 111 may not be a single hole but be formed by combining a plurality of holes. The first sound hole 111 refers to a hole structure provided on the first substrate 11, penetrating the first substrate 11 so that sound is introduced. In an alternative embodiment, the first sound hole 111 may be formed by five through holes distributed side by side. Design first sound hole 111 for a plurality of holes help tentatively stopping during external impurity gets into heavy groove by first sound hole 111, also can play the effect that reduces the air current and strike, avoid water proof membrane 3 to receive strong air current to strike and damage.

In an alternative embodiment, the second sound hole 121 is composed of a plurality of holes distributed on the second substrate 12. This helps to block impurities from entering the inner cavity of the MEMS chip 2, reducing the impact of sound on the MEMS chip 2.

In another alternative embodiment, the first sound hole 111 is composed of a plurality of holes distributed on the first substrate 11, and the second sound hole 121 is composed of a plurality of holes distributed on the second substrate 12. This can block that external impurity gets into by first sound hole 111 and holds the chamber 13 in, also can play the effect that reduces the air current and strike, avoids waterproof membrane 3 to receive strong air current to strike and damage, can effectively block impurity simultaneously again and get into in the inner chamber of MEMS chip 2, reduces the impact force of sound to MEMS chip 2. Sound can more steadily get into in the inner chamber of MEMS chip 2 through first sound hole 111, waterproof membrane 3, second sound hole 121 in proper order to be convenient for MEMS chip 2 accurately converts sound signal into the signal of telecommunication, improves the acoustic performance of microphone.

Optionally, the first substrate 11 and the second substrate 12 are soldered to form an electrical connection. In embodiments where the second substrate 12 is fixed to the first substrate 11 by soldering, the second substrate 12 may be electrically connected to the first substrate 11 by soldering. Further, a circuit may be formed in the second substrate 12, and the MEMS chip 2 may be electrically connected to the ASIC chip 5 through the second substrate 12.

In addition, the embodiment provides an electronic product. The electronic product comprises a product main body and the MEMS microphone. A MEMS microphone is disposed in the product body, the MEMS microphone being configured for receiving sound for conversion into a sound signal. The electronic product can effectively prevent dust and liquid foreign matters from entering the MEMS microphone, so that the reliability of the MEMS microphone is improved, and the electronic product has higher reliability and good acoustic performance.

Although certain specific embodiments of the present invention have been described in detail by way of example, it should be understood by those skilled in the art that the foregoing examples are for purposes of illustration only and are not intended to limit the scope of the invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A MEMS microphone, comprising:

a MEMS chip disposed on the combination substrate;

2. The MEMS microphone of claim 1, further comprising a package cover, wherein the package cover is disposed on the combined substrate, the package cover and the combined substrate form a back cavity, and the MEMS chip is located in the back cavity.

3. The MEMS microphone of claim 1, wherein a side surface of the first substrate close to the second substrate is formed with a sinking groove, and the sinking groove and the second substrate enclose to form the accommodating cavity;

4. The MEMS microphone of claim 1, wherein a corresponding and uniform-sized sunken groove is formed on a surface of the first substrate adjacent to the second substrate and a surface of the second substrate adjacent to the first substrate, and the sunken grooves are fastened to form the accommodating cavity.

5. The MEMS microphone of claim 3 or 4, wherein the shape of the water-proof membrane matches the shape of the sink.

6. The MEMS microphone of claim 3 or 4, wherein the depth of the sinker is less than half the thickness of the first substrate and/or the second substrate on which it is formed.

7. The MEMS microphone of claim 1, wherein an edge of the waterproof membrane is adhesively fixed to a bottom surface of the receiving cavity.

8. The MEMS microphone of claim 1, wherein a first gap is formed between the central region of the water-repellent membrane and the first substrate;

9. The MEMS microphone of claim 1, wherein the first acoustic aperture is composed of a plurality of holes distributed on the first substrate;

and/or the presence of a gas in the gas,

10. The MEMS microphone of claim 1, wherein the first substrate and the second substrate are soldered to form an electrical connection.

11. An electronic product, comprising: a product body and a MEMS microphone according to any of claims 1-10, the MEMS microphone being disposed in the product body, the MEMS microphone being configured for receiving sound for conversion into a sound signal.