CN111757230A

CN111757230A - MEMS microphone and electronic equipment

Info

Publication number: CN111757230A
Application number: CN202010898501.1A
Authority: CN
Inventors: 端木鲁玉; 付博; 张硕
Original assignee: Weifang Goertek Microelectronics Co Ltd
Current assignee: Weifang Goertek Microelectronics Co Ltd
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2020-10-09

Abstract

The invention discloses an MEMS microphone and an electronic device. MEMS microphone includes the shell and locates sensor chip in the shell, the shell includes that shielding piece, one end are uncovered casing that sets up, locate the bottom plate of the open end of casing and locating the first shielding layer of the surface of casing, be equipped with the sound hole on the casing, the shielding piece cover in sound hole department, be equipped with on the shielding piece with the through-hole of sound hole intercommunication. In this way, the first shielding layer, the shielding member and the like can form comprehensive shielding protection for internal components such as the sensor chip in the shell, so as to prevent external electromagnetic interference.

Description

MEMS microphone and electronic equipment

Technical Field

The invention relates to the technical field of sensors, in particular to an MEMS microphone and electronic equipment.

Background

An MEMS (micro electro mechanical system) microphone is an acoustic-electric transducer manufactured based on MEMS technology and has the characteristics of small volume, good frequency response characteristic, low noise and the like. With the development of miniaturization and lightness of electronic devices, MEMS microphones are increasingly widely used in electronic devices with sound-electricity conversion functions, such as mobile phones, tablet computers, cameras, hearing aids, smart toys, and monitoring devices.

In the related art, the MEMS microphone includes a housing, a sensor chip and the like provided in the housing. However, the shielding performance of the housing is weak, so that the MEMS microphone is easily interfered by external factors (such as electromagnetic waves, etc.), thereby affecting the performance of the MEMS microphone.

Disclosure of Invention

The invention mainly aims to provide an MEMS microphone and electronic equipment, and aims to solve the technical problem that the shielding performance of a shell of the MEMS microphone is weak.

To achieve the above object, the present invention provides a MEMS microphone, including:

the shell comprises a shielding piece, a shell with one open end, a bottom plate arranged at the open end of the shell and a first shielding layer, wherein the shell is provided with a sound hole, and the first shielding layer is arranged on the outer surface of the shell; the shielding piece covers the sound hole, and a through hole communicated with the sound hole is formed in the shielding piece; and

a sensor chip disposed within the housing.

Optionally, the shield is provided on an outer surface of the housing to cover the acoustic aperture.

Optionally, the first shielding layer is shorted to the shield.

Optionally, the shield is provided on an outer surface of the housing to cover the sound hole;

the first shielding layer is in the outside of phonic hole forms the holding annular groove, the shielding part is located in the holding annular groove, so that the first shielding layer with the shielding part short circuit.

Optionally, the first shielding layer is a metal layer, or the first shielding layer is a nickel-coated graphite layer; and/or the presence of a gas in the gas,

the shielding part is a metal part, or the shielding part is a nickel-coated graphite conductive rubber part; and/or the presence of a gas in the gas,

the first shielding layer is a vacuum coating; and/or the presence of a gas in the gas,

the shielding part is arranged in a plate shape or a sheet shape.

Optionally, a plurality of concave points or convex points are distributed on the outer surface of the shell; and/or the presence of a gas in the gas,

the first shielding layer is also arranged on the circumferential surface of the bottom plate; and/or the presence of a gas in the gas,

the through-hole is provided with a plurality of.

Optionally, the housing further includes a second shielding layer disposed on the inner surfaces of the housing and the bottom plate.

Optionally, the casing includes a top plate disposed opposite to the bottom plate, and a surrounding plate disposed on a periphery of the top plate, the surrounding plate forms an opening at an end far from the top plate, and the sound hole is disposed on the top plate; the sensor chip is arranged on the top plate and corresponds to the sound hole.

Optionally, the MEMS microphone further includes an ASIC chip disposed on the top plate, and the ASIC chip is electrically connected to the sensor chip;

the bottom plate with the roof is the circuit board, ASIC chip with the roof electricity is connected, MEMS microphone still including bury underground in electric connector in the bounding wall, the surface of bottom plate is equipped with the electric connection portion, electric connector connect ASIC chip with the electric connection portion.

The invention also proposes an electronic device comprising a MEMS microphone as described above.

According to the MEMS microphone, the first shielding layer is arranged on the outer surface of the shell, and the first shielding layer and the substrate can form a shielding structure surrounding the shell and the sensor chip, so that the shielding performance of the shell can be improved, and electromagnetic interference in the external environment can be prevented from entering the shell. And, through set up the shielding piece that covers the sound hole in sound hole department and set up the through-hole with the sound hole intercommunication on the shielding piece, the shielding piece can be used to block outside electromagnetic interference to reduce the risk that outside electromagnetic interference gets into in the shell from the sound hole, and outside vibration gas accessible through-hole gets into in the shell, thereby can further improve the shielding performance of shell, in order to prevent that the electromagnetic interference in the external environment from getting into in the shell, and then can improve MEMS microphone's performance.

Thus, the MEMS microphone of the present invention can form a complete shield for internal components such as the sensor chip in the housing through the first shielding layer and the shielding member, so as to prevent external electromagnetic interference.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

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

fig. 2 is a schematic structural diagram of another embodiment of the MEMS microphone of the present invention.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				100	MEMS microphone	16	First solder paste welding part
10	Outer casing	17	Second solder paste soldering part
				11	Shell body	18	A first protective part
111	Top board	181	First inner protective layer
				112	Boarding board	182	A first outer protective layer
113	Sound hole	19	Second protective part
				12	Base plate	191	Second inner protective layer
121	Electrical connection part	192	Second outer protective layer
				13	First shielding layer	20	Sensor chip
131	Containing ring groove	21	Substrate
				14	Second shielding layer	22	Induction film
15	Shielding element	30	ASIC chip
				151	Through hole	40	Electrical connector

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that if the description of "first", "second", etc. is provided in the embodiment of the present invention, the description of "first", "second", etc. is only for descriptive purposes and is not to be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

In addition, the meaning of "and/or" appearing throughout is to include three juxtapositions, exemplified by "A and/or B" including either scheme A, or scheme B, or a scheme in which both A and B are satisfied.

The invention provides an MEMS microphone and an electronic device.

The MEMS microphone is used for electronic equipment, so that the electronic equipment has an acoustic-electric conversion function.

The electronic device may be, but not limited to, an electronic device with an audio-electrical conversion function, such as a mobile phone, a tablet computer, a camera, a hearing aid, a smart toy, and a monitoring device.

In an embodiment of the present invention, as shown in fig. 1, the MEMS microphone 100 includes:

the casing 10 comprises a shielding piece 15, a casing 11 with one open end, a bottom plate 12 arranged at the open end of the casing 11 and a first shielding layer 13, wherein the casing 11 is provided with a sound hole 113, and the first shielding layer 13 is arranged on the outer surface of the casing 11; the shielding piece 15 is arranged at the sound hole 113, the shielding piece 15 covers the sound hole 113, and a through hole 151 communicated with the sound hole 113 is arranged on the shielding piece 15; and

a sensor chip 20, the sensor chip 20 being provided within the housing 10.

Wherein, the first shielding layer 13 and the shielding piece 15 have electromagnetic shielding function. In use, the first shield layer 13 and shield 15 are grounded.

As such, by providing the first shielding layer 13 on the outer surface of the housing 11, the first shielding layer 13 and the substrate can form a shielding structure surrounding the housing 11 and the sensor chip 20, so as to improve the shielding performance of the housing 10, and prevent the electromagnetic interference in the external environment from entering the housing 10. Furthermore, by providing the shielding member 15 for sealing the sound hole 113 at the sound hole 113 and providing the through hole 151 communicating with the sound hole 113 on the shielding member 15, the shielding member 15 can be used to block external electromagnetic interference to reduce the risk of external electromagnetic interference entering the housing 10 from the sound hole 113, and external vibration gas can enter the housing 10 through the through hole 151, so that the shielding performance of the housing 10 can be further improved to prevent electromagnetic interference in the external environment from entering the housing 10, and further, the performance of the MEMS microphone 100 can be improved.

Therefore, by providing the first shielding layer 13, the shielding member 15, and the like, a shielding structure with good continuity can be formed to shield and protect the internal components such as the sensor chip 20 and the like in the housing 10 more comprehensively to prevent external electromagnetic interference.

In the embodiment, the number of the through holes 151 may be set to one, or the through holes 151 may be provided in plural (i.e., greater than or equal to two).

In the present embodiment, the through hole 151 is provided in plurality. Thus, each through hole 151 can be made small, and the shielding effect of the shield 15 against external electromagnetic signals can be improved.

In the embodiment, the manner of sealing the sound hole 113 by the shielding member 15 is many, for example, the shielding member 15 may be disposed on the outer surface of the housing 11 to cover the sound hole 113, i.e., to seal the sound hole 113; the shielding member 15 may also be disposed in the sound hole 113 to seal the sound hole 113, i.e. to seal the sound hole 113; and so on.

In this embodiment. The shield 15 is provided on the outer surface of the housing 11 to cover the sound hole 113. Thus, the difficulty of mounting the shield 15 can be reduced, and the mounting efficiency of the MEMS sensor can be improved.

Further, as shown in fig. 1, the first shielding layer 13 is shorted with the shield 15. In this way, the shielding performance of the housing 10 can be further improved. In use, it is only necessary to ground either the first shield layer 13 or the shield 15, i.e., both are grounded.

In this embodiment, as shown in fig. 1, the first shielding layer 13 forms an accommodating ring groove 131 outside the acoustic hole 113, and the shielding element 15 is disposed in the accommodating ring groove 131, so that the first shielding layer 13 is short-circuited with the shielding element 15. In this way, the shorting stability of the first shield layer 13 and the shield 15 can be improved.

Further, as shown in fig. 1, the first shielding layer 13 is also provided on the circumferential surface of the bottom plate 12. In this way, the shielding performance at the joint of the housing 11 and the substrate can be improved, and the shielding performance of the case 10 can be further improved.

Further, a plurality of concave points or convex points are distributed on the outer surface of the shell 11. In this way, the connection area of the first shield layer 13 and the outer surface of the housing 11 can be increased, so that the connection stability of the first shield layer 13 and the housing 11 can be enhanced.

In a specific embodiment, the first shielding layer 13 and/or the shielding member 15 may be made of a metal material, or may be made of other conductive materials (such as nickel-coated graphite). For example, in some embodiments, the first shielding layer 13 is a metal layer, and/or the shielding member 15 is a metal member. For another example, in another embodiment, the first shielding layer 13 is a nickel-coated graphite layer, and/or the shielding member 15 is a nickel-coated graphite conductive rubber member.

In the embodiment, the first shielding layer 13 is formed in various manners, such as electroplating, spraying, etc.

In this embodiment, the first shielding layer 13 is vacuum plated. When the MEMS microphone 100 is assembled, the first shield layer 13 may be formed on the outer surface of the case 11 by vacuum plating or the like after the case 11 is mounted on a substrate.

It should be noted that the first shielding layer 13 may be a single layer structure, or may be a multi-layer structure (e.g., a plurality of different metals are used to form a multi-layer structure of different metal layers) to improve the shielding effect.

In order to simplify the structure of the shielding element 15 and facilitate installation, the shielding element 15 may be configured in a plate shape or a sheet shape, i.e. the shielding element 15 is the shielding sheet or the shielding plate.

Further, as shown in fig. 1, the housing 11 includes a top plate 111 disposed opposite to the bottom plate 12, and a surrounding plate 112 disposed at a periphery of the top plate 111, the surrounding plate 112 forms an opening at an end away from the top plate 111, and the sound hole 113 is disposed at the top plate 111; the sensor chip 20 is disposed on the top plate 111 and corresponds to the sound hole 113. That is, the bottom plate 12 and the top plate 111 are respectively provided at both ends of the enclosure 112, i.e., the enclosure 112 connects the bottom plate 12 and the top plate 111.

Specifically, the sensor chip 20 includes a substrate 21 and a sensing film 22 disposed on the substrate 21, the substrate 21 is disposed on the top plate 111, and the sensing film 22 is disposed opposite to the sound hole 113.

Thus, the vibrating air enters the case 10 from the through hole 151 and the sound hole 113, and drives the sensing film 22 to vibrate, so that the sensor chip 20 generates an electrical signal.

Further, as shown in fig. 1, the MEMS microphone 100 further includes an ASIC (application Specific Integrated circuit) chip 30 disposed in the housing 10, and the ASIC chip 30 is electrically connected to the sensor chip 20 to process an electrical signal generated by the sensor chip 20. The ASIC chip 30 is disposed on the top plate 111.

Further, as shown in fig. 1, the bottom plate 12 and the top plate 111 are both circuit boards, the ASIC chip 30 is electrically connected to the top plate 111, the MEMS microphone 100 further includes an electrical connector 40 embedded in the enclosure 112, an electrical connection portion 121 for electrically connecting to an external circuit is disposed on an outer surface of the bottom plate 12, and the electrical connector 40 connects the ASIC chip 30 and the electrical connection portion 121.

As such, when the MEMS microphone 100 is used in an electronic device, the base plate 12 may be mounted on a main control board of the electronic device while the electrical connection portion 121 is electrically connected to the main control board, so as to electrically connect the sensor chip 20 with an external circuit (i.e., a circuit of the electronic device).

Wherein the first shielding layer 13 or the shielding member 15 is electrically connected to the top plate 111 to realize grounding.

It should be particularly emphasized here that since the first shielding layer 13 is provided on the outer surface of the housing 11, the shielding performance at the joint of the top plate 111 and the enclosure 112 can be improved, and thus the shielding performance of the housing 10 can be improved.

Further, as shown in fig. 1, the housing 10 further includes a second shielding layer 14 disposed on the inner surfaces of the housing 11 and the bottom plate 12. In this way, the shielding performance of the housing 10 can be further improved.

In an embodiment, the shielding layers may be formed on the inner surfaces of the top plate 111, the bottom plate 12 and the enclosure plate 112 before assembly, and the second shielding layer 14 may be formed on the inner surfaces of the housing 11 and the bottom plate 12 after assembly. However, the second shielding layer 14 formed in this way has a plurality of discontinuous portions, and the continuity of the shielding structure can be improved by providing the first shielding layer 13 on the outer surface of the housing 11, so that the shielding performance of the housing 10 can be improved.

In a specific embodiment, the second shielding layer 14 can be made of a metal material, or can be made of other conductive materials (such as nickel-coated graphite). For example, in some embodiments, the second shielding layer 14 is a metal layer. As another example, in some embodiments, the second shielding layer 14 is a nickel-coated graphite layer.

It should be noted that the second shielding layer 14 may be a single layer structure or a multi-layer structure (e.g., a plurality of different metals are used to form a multi-layer structure of different metal layers) to improve the shielding effect.

It can be understood that a first notch is formed at the position of the first shielding layer 13 corresponding to the sound hole 113; a second notch is formed on the second shielding layer 14 corresponding to the sound hole 113.

The connection between the bottom plate 12 and the enclosure 112, and the connection between the top plate 111 and the enclosure 112, will be described below.

Alternatively, the bottom plate 12 and the enclosure plate 112 may be connected by solder paste welding, adhesive bonding, or the like, and similarly, the top plate 111 and the enclosure plate 112 may be connected by solder paste welding, adhesive bonding, or the like.

In another embodiment of the present invention, the bottom plate 12 and the surrounding plate 112, and the top plate 111 and the surrounding plate 112 are connected by solder paste.

Specifically, as shown in fig. 2, the housing 10 further includes a first solder paste soldering portion 16 and a second solder paste soldering portion 17, wherein the first solder paste soldering portion 16 is disposed between the top plate 111 and the surrounding plate 112 to connect the top plate 111 and the surrounding plate 112; the second solder paste soldering portion 17 is disposed between the base plate 12 and the surrounding plate 112 to connect the base plate 12 and the surrounding plate 112.

It is understood that when assembling the MEMS microphone 100, the top plate 111 and the surrounding plate 112 may be soldered using solder paste, such that a first solder paste solder 16 is formed between the top plate 111 and the surrounding plate 112; and the shroud 112 may be soldered to the base plate 12 using solder paste, such that a second solder paste solder 17 is formed between the shroud 112 and the base plate 12.

In this embodiment, as shown in fig. 2, the housing 10 further includes a first protection portion 18 and a second protection portion 19, the first protection portion 18 is disposed on the surface of the first solder paste welding portion 16, and the second protection portion 19 is disposed on the surface of the second solder paste welding portion 17.

In this way, the risk of melting and cracking of the first solder paste welding portion 16 and the second solder paste welding portion 17 at high temperature (e.g., when the MEMS microphone 100 is welded to an electronic device, or during the use of the electronic device) can be reduced or even avoided, so as to ensure the sealing property of the housing 10 and avoid air leakage; the risk of the solder flux in the first solder paste soldering portion 16 and the second solder paste soldering portion 17 bursting is reduced or even avoided, so that the MEMS microphone 100 is prevented from being polluted, the stability and reliability of the MEMS microphone 100 and the electronic device are improved, and the service life of the MEMS microphone 100 is prolonged.

In this embodiment, further, the first protection portion 18 is also used for connecting the top plate 111 and the enclosing plate 112; and/or the second guard 19 may also be used to connect the base plate 12 to the enclosure 112. Thus, the connection strength and the connection stability of the top plate 111 and the coaming 112 can be improved; and/or the strength and stability of the connection of the base 12 to the shroud 112 may be improved.

Specifically, the first protection part 18 is a glue connection part; and/or the second protective part 19 is a glue connection part.

Alternatively, the first protection portion 18 and/or the second protection portion 19 may be formed by a curing adhesive with high temperature resistance, such as a silicon gel or an epoxy resin adhesive, or other high temperature resistant curing adhesive.

Of course, in other embodiments, the first protection portion 18 and/or the second protection portion 19 may also be formed by paint with high temperature resistance.

In this embodiment, as shown in fig. 2, a plurality of the first solder paste welding portions 16 are annularly spaced, and the top plate 111 and the surrounding plate 112 form a first structural gap between the adjacent first solder paste welding portions 16. The first guard 18 is also disposed within the first structural gap to sealingly connect the top plate 111 and the shroud 112.

In this embodiment, as shown in fig. 2, a plurality of second solder paste welding portions 17 are annularly and alternately distributed, and a second structural gap is formed between the adjacent second solder paste welding portions 17 between the bottom plate 12 and the surrounding plate 112. The second guard 19 is also disposed within the second structural gap to sealingly connect the base 12 to the enclosure 112.

Therefore, the consumption of the solder paste can be reduced, so that the top plate 111 and the coaming 112 (or the bottom plate 12 and the coaming 112) can be connected in a mode of connecting a plurality of welding points by using less solder paste to reduce the cost; the first structural gap (or the second structural gap) formed by two adjacent first solder paste welding parts 16 (or the second solder paste welding parts 17) can be connected through the first protection part 18 (or the second protection part 19), and the connection strength and the sealing property of the top plate 111 and the enclosure plate 112 (or the bottom plate 12 and the enclosure plate 112) can be ensured.

Moreover, since the amount of solder paste is reduced, it is not only convenient to provide the first protection portion 18 (or the second protection portion 19), but also possible to further reduce the risk of melting and cracking of the first solder paste welding portion 16 (or the second solder paste welding portion 17) at high temperature and the flux thereof bursting, so as to further improve the stability and reliability of the MEMS microphone 100 and the electronic device.

Of course, in other embodiments, the first solder paste soldering portion 16 and/or the second solder paste soldering portion 17 may be configured in other configurations; for example, one may: the first solder paste welding part 16 is an annular part; and/or the second solder paste welding part 17 is an annular part. As another example, one may: the first solder paste welding portions 16 are annularly distributed at intervals, and the second solder paste welding portions 17 are annular members. As another example, one can: the first solder paste welding portions 16 are annular members, and the second solder paste welding portions 17 are annularly and alternately distributed. And so on.

In this embodiment, further, as shown in fig. 2, the first protective portion 18 includes a first inner protective layer 181 provided inside the first solder paste welding portion 16; and/or the presence of a gas in the gas,

the first protection portion 18 includes a first outer protection layer 182 disposed outside the first solder paste welding portion 16; and/or the presence of a gas in the gas,

the second protective portion 19 includes a second inner protective layer 191 provided inside the second solder paste welding portion 17; and/or the presence of a gas in the gas,

the second protective portion 19 includes a second outer protective layer 192 disposed outside the second solder paste welding portion 17.

Wherein, the inner side of the first solder paste welding portion 16 refers to the side of the first solder paste welding portion 16 located inside the housing 10, and the outer side of the first solder paste welding portion 16 refers to the side of the first solder paste welding portion 16 located outside the housing 10; the inner side of the second solder paste welding portion 17 refers to the side of the second solder paste welding portion 17 located inside the housing 10, and the outer side of the second solder paste welding portion 17 refers to the side of the second solder paste welding portion 17 located outside the housing 10.

It can be understood that, for the first solder paste welding portion 16, it is only necessary to provide the first protection portion 18 inside or outside the first solder paste welding portion 16, so as to reduce the risk of melting and cracking of the first solder paste welding portion 16 at high temperature and the risk of flux cracking.

Similarly, for the second solder paste soldering portion 17, the second protection portion 19 only needs to be disposed inside or outside the second solder paste soldering portion 17, so as to reduce the risk of melting and cracking of the second solder paste soldering portion 17 at high temperature and the risk of flux cracking. In practical applications, for example, the second protection portion 19 may include both the second inner protection layer 191 and the second outer protection layer 192, so that the risk of melting, cracking and bursting of the second solder paste welding portion 17 at high temperature can be more thoroughly prevented; it is also possible to make the second protective part 19 only comprise the second inner protective layer 191 or the second outer protective layer 192 to reduce material usage.

It should be noted that, for the first solder paste welding portion 16, in the case of the scheme that "the first solder paste welding portion 16 is annularly and intermittently distributed in a plurality", the first protection portion 18 further includes a first connecting sealing section disposed at the first structure gap, and the first connecting sealing section seals the first structure gap and connects the top plate 111 and the enclosing plate 112; the first connecting seal connects the first inner protective layer 181 and the first outer protective layer 182.

It should be noted that, for the second solder paste welding portion 17, in the case of the scheme that "the second solder paste welding portion 17 is annularly and intermittently distributed", the second protection portion 19 further includes a second connecting sealing section disposed at the second structural gap, and the second connecting sealing section seals the second structural gap and connects the bottom plate 12 and the enclosing plate 112; the second connecting seal segment connects the second inner protective layer 191 and the second outer protective layer 192.

In this embodiment, as shown in fig. 2, the first protection portion 18 includes a first inner protection layer 181 disposed inside the first solder paste welding portion 16 and a first outer protection layer 182 disposed outside the first solder paste welding portion 16, and the second protection portion 19 includes a second inner protection layer 191 disposed inside the second solder paste welding portion 17 and a second outer protection layer 192 disposed outside the second solder paste welding portion 17.

In some embodiments based on this embodiment, the first protection portion 18 includes a first inner protection layer 181 disposed on the inner side of the first solder paste welding portion 16, and a first outer protection layer 182 disposed on the outer side of the first solder paste welding portion 16, and a longitudinal cross-sectional area of the first outer protection layer 182 is smaller than a longitudinal cross-sectional area of the first inner protection layer 181; and/or the presence of a gas in the gas,

the second protection portion 19 includes a second inner protection layer 191 disposed on the inner side of the second solder paste welding portion 17 and a second outer protection layer 192 disposed on the outer side of the second solder paste welding portion 17, and the longitudinal cross-sectional area of the second outer protection layer 192 is smaller than the longitudinal cross-sectional area of the second inner protection layer 191.

The longitudinal section is a section perpendicular to the enclosure and the top plate 111 or the bottom plate 12.

It is understood that, since the internal components such as the sensor chip 20 are disposed in the casing 10, in order to better prevent the internal components from being contaminated by the solder paste welding portion, the protection capability of the first protection portion 18 (or the second protection portion 19) to the inner side of the first solder paste welding portion 16 (or the second solder paste welding portion 17) needs to be increased, for example, the thickness of the first inner protection layer 181 (or the thickness of the second inner protection layer 191) may be increased, so that the longitudinal cross-sectional area of the first inner protection layer 181 is larger than the longitudinal cross-sectional area of the first outer protection layer 182 (or the longitudinal cross-sectional area of the second inner protection layer 191 is larger than the longitudinal cross-sectional area of the second outer protection layer 192).

In some embodiments based on this embodiment, as shown in the figures, the first guard 18 has a smaller longitudinal cross-sectional area than the second guard 19.

It will be appreciated that when the MEMS microphone 100 is used on an electronic device, the base plate 12 is attached to the main control board of the electronic device. That is, the temperature at the bottom plate 12 is generally higher than that at the top plate 111, so that the protection capability of the second protection portion 19 against the second solder paste welding portion 17 needs to be enhanced, for example, the thickness of the second protection portion 19 can be increased, so that the longitudinal cross-sectional area of the second protection portion 19 is smaller than that of the first protection portion 18.

In addition, the technical solutions in the above embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A MEMS microphone, comprising:

the shell comprises a shielding piece, a first shielding layer, a shell body with one end arranged in an open manner and a bottom plate arranged at the open end of the shell body, wherein the shell body is provided with a sound hole, and the first shielding layer is arranged on the outer surface of the shell body; the shielding piece covers the sound hole, and a through hole communicated with the sound hole is formed in the shielding piece; and

a sensor chip disposed within the housing.

2. The MEMS microphone of claim 1, wherein the shield is disposed on an outer surface of the housing to cover the acoustic aperture.

3. The MEMS microphone of claim 1, wherein the first shield layer is shorted to the shield.

4. The MEMS microphone of claim 3, wherein the shield is provided on an outer surface of the housing to cover the acoustic aperture; the first shielding layer is in the outside of phonic hole forms the holding annular groove, the shielding part is located in the holding annular groove, so that the first shielding layer with the shielding part short circuit.

5. The MEMS microphone of claim 1, wherein the first shielding layer is a metal layer, or wherein the first shielding layer is a nickel-coated graphite layer; and/or the presence of a gas in the gas,

the shielding part is arranged in a plate shape or a sheet shape.

6. The MEMS microphone of any one of claims 1 to 5, wherein the outer surface of the housing has a plurality of pits or bumps distributed thereon; and/or the presence of a gas in the gas,

the through-hole is provided with a plurality of.

7. The MEMS microphone of any one of claims 1 to 5, wherein the housing further comprises a second shielding layer disposed on the inner surfaces of the housing and the bottom plate.

8. The MEMS microphone of any one of claims 1 to 5, wherein the housing comprises a top plate disposed opposite the bottom plate, and a surrounding plate disposed at a periphery of the top plate, the surrounding plate forming an opening at an end away from the top plate, the sound hole being disposed at the top plate; the sensor chip is arranged on the top plate and corresponds to the sound hole.

9. The MEMS microphone of claim 8, further comprising an ASIC chip disposed on the top plate, the ASIC chip being electrically connected to the sensor chip;

10. An electronic device, characterized in that it comprises a MEMS microphone according to any one of claims 1 to 9.