阅读说明：本技术 防尘mems模组、麦克风装置以及电子设备 (Dustproof MEMS module, microphone device and electronic equipment ) 是由 刘波 于 2021-08-13 设计创作，主要内容包括：本公开涉及一种防尘MEMS模组、麦克风装置以及电子设备。所述防尘MEMS模组包括：电路板和防尘膜；所述电路板具有相背设置的第一表面和第二表面,所述电路板上开设有贯穿所述第一表面和所述第二表面的通孔；所述电路板的第二表面凹陷形成有凹陷槽,所述凹陷槽与所述通孔连通；所述凹陷槽的底面具有连接部；所述防尘膜的第一表面上设置有金属层,所述金属层与所述连接部焊接,以使所述防尘膜设置在所述凹陷槽内并覆盖所述通孔。(The present disclosure relates to a dustproof MEMS module, a microphone device, and an electronic apparatus. The dustproof MEMS module includes: a circuit board and a dust-proof film; the circuit board is provided with a first surface and a second surface which are arranged oppositely, and a through hole penetrating through the first surface and the second surface is formed in the circuit board; a concave groove is formed on the second surface of the circuit board in a concave mode and is communicated with the through hole; the bottom surface of the concave groove is provided with a connecting part; and a metal layer is arranged on the first surface of the dustproof film and welded with the connecting part, so that the dustproof film is arranged in the concave groove and covers the through hole.)

1. A dustproof MEMS module, characterized by includes: a circuit board and a dust-proof film;

the circuit board is provided with a first surface and a second surface which are arranged oppositely, and a through hole penetrating through the first surface and the second surface is formed in the circuit board;

a concave groove is formed on the second surface of the circuit board in a concave mode and is communicated with the through hole;

the bottom surface of the concave groove is provided with a connecting part;

and a metal layer is arranged on the first surface of the dustproof film and welded with the connecting part, so that the dustproof film is arranged in the concave groove and covers the through hole.

2. The dustproof MEMS module of claim 1, wherein the connection portion is a copper foil disposed on a bottom surface of the concave groove.

3. The dustproof MEMS module of claim 1, wherein the connection portion is a pad disposed on a bottom surface of the recess groove.

4. The dustproof MEMS module of claim 1, wherein the second surface of the dustproof membrane is provided with a waterproof membrane, the waterproof membrane is spaced apart from the dustproof membrane, and the first surface of the dustproof membrane and the second surface of the dustproof membrane are opposite to each other.

5. The dustproof MEMS module according to claim 4, wherein an isolation film is disposed between the dustproof film and the waterproof film, one surface of the isolation film is fixedly connected with the second surface of the dustproof film, and the other surface of the isolation film is fixedly connected with the waterproof film.

6. The dustproof MEMS module of claim 5, wherein the thickness of the isolation film is in a range of 45 μm to 55 μm.

7. The dustproof MEMS module of claim 1, wherein the second surface of the dustproof membrane is provided with a conductive layer, and the first surface of the dustproof membrane and the second surface of the dustproof membrane are arranged oppositely.

8. The dustproof MEMS module of claim 1 or 5, wherein the dustproof film is made of metal.

9. The dustproof MEMS module according to claim 1, comprising a housing, wherein the housing is covered on the first surface of the circuit board and encloses with the circuit board to form a containing cavity, and the containing cavity is communicated with the through hole.

10. The dustproof MEMS module of claim 1, wherein the circuit board has a plurality of through holes formed therethrough, the through holes being spaced apart from each other.

11. A microphone device comprising the dustproof MEMS module according to any one of claims 1 to 10, and a MEMS microphone chip and an ASIC chip;

the circuit board and the shell are enclosed to form an accommodating cavity, and the MEMS microphone chip and the ASIC chip are arranged in the accommodating cavity.

12. An electronic device, characterized in that it comprises a microphone arrangement according to claim 11.

Technical Field

The present disclosure relates to the field of electroacoustic conversion technologies, and more particularly, to a dustproof MEMS module, a microphone device, and an electronic apparatus.

Background

In order to prevent the chip inside the miniature microphone from being affected by external powder, particles and moisture, and therefore the service life of the miniature microphone is shortened, under the ordinary condition, a miniature microphone dustproof device is required to be designed at the communication position (such as a through hole) between the inside of the miniature microphone and the outside, the miniature microphone chip is separated from the outside environment through the miniature microphone dustproof device, and the miniature microphone chip is protected.

However, the conventional micro microphone dust-proof device is connected to the micro microphone by an adhesive, and when the conventional micro microphone is used in a humid or other severe environment, the adhesive force of the adhesive is reduced, and the dust-proof film device is easily detached.

Disclosure of Invention

An object of the present disclosure is to provide a dustproof MEMS module, a microphone device, and an electronic apparatus.

According to a first aspect of the present disclosure, a dust-proof MEMS module is provided. The dustproof MEMS module includes: a circuit board and a dust-proof film;

the circuit board is provided with a first surface and a second surface which are arranged oppositely, and a through hole penetrating through the first surface and the second surface is formed in the circuit board;

a concave groove is formed on the second surface of the circuit board in a concave mode and is communicated with the through hole;

the bottom surface of the concave groove is provided with a connecting part;

and a metal layer is arranged on the first surface of the dustproof film and welded with the connecting part, so that the dustproof film is arranged in the concave groove and covers the through hole.

Optionally, the connection portion is a copper foil disposed on a bottom surface of the concave groove.

Optionally, the connection portion is a pad disposed on a bottom surface of the recessed groove.

Optionally, a waterproof film is disposed on the second surface of the dustproof film, and the waterproof film is connected with the dustproof film through an adhesive.

Optionally, an isolation film is disposed between the dustproof film and the waterproof film, one surface of the isolation film is fixedly connected to the second surface of the dustproof film, and the other surface of the isolation film is fixedly connected to the waterproof film.

Optionally, the thickness of the isolation film ranges from 45 μm to 55 μm.

Optionally, a conductive layer is disposed on the second surface of the dustproof film.

Optionally, the dustproof film is made of a metal material.

Optionally, the printed circuit board assembly comprises a housing, the housing is covered on the first surface of the circuit board and encloses with the circuit board to form an accommodating cavity, and the accommodating cavity is communicated with the through hole.

Optionally, the circuit board is provided with a plurality of through holes penetrating through the first surface and the second surface, and the through holes are arranged at intervals.

According to a second aspect of the present disclosure, a microphone apparatus is provided. The microphone device comprises the dustproof MEMS module, an MEMS microphone chip and an ASIC chip, wherein the dustproof MEMS module is arranged on the first side of the microphone device;

the circuit board and the shell enclose to form an accommodating cavity, and the MEMS microphone chip and the ASIC chip are arranged in the accommodating cavity.

According to a third aspect of the present disclosure, an electronic device is provided. The electronic device comprises the microphone apparatus of the second aspect.

One technical effect of the present disclosure is to provide a dustproof MEMS module. The dustproof MEMS module comprises a circuit board and a dustproof film. And arranging a metal layer on the dustproof film, forming a concave groove on the second surface of the circuit board, wherein the bottom surface of the concave groove is provided with a connecting part, and the metal layer is welded with the connecting part. Compared with the dustproof film and the circuit board which are connected in a bonding mode, the dustproof film and the circuit board are connected in a reliable mode.

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

Drawings

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

Fig. 1 is a schematic structural diagram of a dustproof MEMS module according to the present disclosure.

Fig. 2 is a schematic structural diagram of a dustproof MEMS module according to the present disclosure.

Fig. 3 is an enlarged view of the structure shown at a in fig. 2.

Fig. 4 is a schematic structural diagram of a third dustproof MEMS module according to the present disclosure.

Description of reference numerals:

1-a circuit board, 11-a first surface of the circuit board, 12-a second surface of the circuit board, 13-a via, 14-a recessed groove, 141-a bottom surface of the recessed groove, 142-a connection; 2-dustproof film, 21-metal layer, 3-shell, 4-waterproof film, 5-welding material, 6-isolation film, 61-first adhesive, 62-second adhesive, 7-conducting layer, 8-MEMS microphone chip and 9-ASIC chip.

Detailed Description

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that: 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 disclosure unless specifically stated otherwise.

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

Techniques and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be considered a 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.

According to one embodiment of the present disclosure, a dustproof MEMS module is provided. The dustproof MEMS module provided by the disclosure can be used for manufacturing an MEMS microphone device. The MEMS microphone device can be applied to various electronic products such as mobile phones, notebook computers, tablet computers, VR equipment and intelligent wearable equipment.

Referring to fig. 1 to 4, the dustproof MEMS module includes: a circuit board 1 and a dust-proof film 2.

The circuit board 1 is provided with a first surface 11 and a second surface 12 which are arranged oppositely, and the circuit board 1 is provided with a through hole 13 which penetrates through the first surface 11 and the second surface 12. The second surface 12 of the circuit board 1 is concavely formed with a concave groove 14, and the concave groove 14 is communicated with the through hole 13. The bottom surface 141 of the concave groove 14 is provided with a connecting portion 142. A metal layer 21 is disposed on the first surface of the dustproof film 2, and the metal layer 21 is welded to the connection portion 142, so that the dustproof film 2 is disposed in the recess 14 and covers the through hole 13.

In other words, the dustproof MEMS module mainly includes a circuit board 1 and a dustproof film 2 mounted on the circuit board 1. Inside dust membrane 2 had avoided impurity such as dust particle among the external environment to get into the microphone, had promoted the dustproof effect of dustproof MEMS module.

The circuit board 1 has a first surface 11 and a second surface 12 opposite to each other. The first surface 11 is provided with acoustic components which are electrically connected to the circuit board 1. The dustproof MEMS module comprises a shell 3 fixedly connected with the circuit board 1 and containing the acoustic assembly, a through hole 13 for sound waves to pass through is formed in the circuit board 1, and the through hole 13 is formed in the position of the acoustic assembly.

The second surface 12 of the circuit board 1 is provided with pads. In the application of the dustproof MEMS module to an electronic device, the circuit board 1 is electrically connected to the electronic device through the pads provided on the second surface 12.

The second surface 12 of the circuit board 1 is recessed to form a recessed groove 14 communicating with the through hole 13, and the dust-proof film 2 is connected to the recessed groove 14. The second surface 12 of the circuit board 1 is sunken to form a sunken groove 14 communicated with the through hole 13, the dustproof film 2 is connected with the sunken groove 14, and compared with the dustproof film 2 which is directly connected with the second surface 12 of the circuit board 1, the dustproof film 2 can be better protected, and the dustproof film 2 is prevented from being damaged during assembly and use. In addition, the second surface 12 of the circuit board 1 is recessed to form a recessed groove 14 communicated with the through hole 13, and the dustproof film 2 is connected with the recessed groove 14, so that the overall height of the dustproof MEMS module can be reduced.

The concave groove 14 is formed on the second surface 12 of the circuit board 1 by, for example, a hole-digging process, and the connection portion 142 is provided on the bottom surface 141 of the concave groove 14. The connecting portion 142 is used for welding with the dust-proof film 2.

A metal layer 21 is provided on the first surface of the dustproof film 2. The metal layer 21 is deposited on the first surface of the dustproof film 2 by, for example, chemical vapor deposition. The dust-proof film 2 is mounted in the recess groove 14 and covers the through hole 13 by welding the metal layer 21 to the connection portion 142.

The through-hole 13 may serve as a sound hole. The through holes 13 may be circular holes, square holes, rectangular holes, elliptical holes, triangular holes, rhombic holes, parallelogram holes, or the like. The technical effect of the disclosure can be realized by the sound holes in various forms, the processing and the manufacturing are more facilitated, and the practicability and the reliability are higher.

Alternatively, the metal layer 21 is provided in the edge area of both ends of the dustproof film 2. For example, the area of the metal layer 21 covering the dust-proof film 2 is 20% to 40% of the first surface area of the dust-proof film 2. Be provided with a plurality of apertures on the dust-proof membrane 2, a plurality of apertures evenly distributed is on dust-proof membrane 2. In this example, in order not to affect the entire dustproof effect of the dustproof film 2 and the entire acoustic performance of the microphone, the metal layer 21 does not entirely cover the first surface of the dustproof film 2, but the metal layers 21 are provided in the edge areas of both ends of the dustproof film 2.

Alternatively, the metal layer 21 may be made of a metal material such as nickel or gold. Alternatively, the metal layer 21 and the connection portion 142 may be welded by the solder 15. The solder 15 may be solder paste or silver paste. Alternatively, the dust-proof film 2 may be made of plastic, metal, or the like.

In the present embodiment, the metal layer 21 is disposed on the dustproof film 2, the concave groove 14 is formed on the second surface 12 of the circuit board 1, the connection portion 142 is disposed on the bottom surface 141 of the concave groove 14, and the metal layer 21 is soldered to the connection portion 142. Compared with the bonding connection of the dustproof film 2 and the circuit board 1, the reliability of the connection of the dustproof film 2 and the circuit board 1 is improved.

In one embodiment, the connection portion 142 is a copper foil disposed on the bottom surface 141 of the recess groove 14.

Specifically, the circuit board 1 includes a circuit board main body and a copper foil provided on the circuit board main body. The circuit board 1 is prepared, for example, using a copper clad laminate. A concave groove 14 is formed on the second surface 12 of the circuit board 1, and a copper foil is coated on the bottom surface 141 of the concave groove 14. The copper foil is soldered to the metal layer 21.

Or the connection portion 142 is a copper foil ring provided on the bottom surface 141 of the concave groove 14. For example, the copper foil ring has a ring structure. For example, the circuit board 1 is provided with fixing holes for fixing the acoustic components. The fixing hole penetrates the first surface 1 of the circuit board 1 and the bottom surface 141 of the recess groove 14. Thus, a first hole is formed on the first surface 11 of the circuit board 1, and a second hole is formed on the bottom surface 141 of the concave groove 14, the first hole and the second hole communicating. A copper foil ring is provided on the periphery of the second hole at the bottom surface 141 of the concave groove 14. The copper foil ring is welded to the metal layer 21.

Optionally, a plurality of welding points are arranged on the copper foil or the copper foil ring, and adjacent welding points are arranged at intervals. After the copper foil or the copper foil ring is welded to the metal layer 21, a welding spot provided on the copper foil or the copper foil ring is welded to the metal layer 21.

In one embodiment, the connection portion 142 is a pad disposed on the bottom surface 141 of the recess groove 14. Specifically, a pad is fixed on the bottom surface 141 of the concave groove 14. One or more pads may be disposed on the bottom surface 141. The pads are soldered to the metal layer 21.

In one embodiment, referring to fig. 2, a waterproof film 4 is disposed on the second surface of the dustproof film 2, the waterproof film 4 is disposed at an interval from the dustproof film 2, and the first surface of the dustproof film 2 and the second surface of the dustproof film 2 are disposed opposite to each other.

Specifically, the dust-proof film 2 has a first surface and a second surface. The first surface of the dust-proof film 2 is used for soldering with the circuit board 1. The second surface of the dust-proof membrane 2 is intended to be connected to the water-proof membrane 4, wherein the dust-proof membrane 2 is indirectly connected to the water-proof membrane 4.

This example is provided with water proof membrane 4 with dust proof membrane 2 interval setting on the second surface of dust proof membrane 2 for dustproof MEMS module has waterproof performance, avoids inside the steam in the external environment flows into dustproof MEMS module from through-hole 13, and damages the internal circuit.

When the dustproof MEMS module works, the dustproof film 2 can vibrate under the action of air flow, and the effective vibration range of the dustproof film 2 is ensured due to the fact that the dustproof film 2 and the waterproof film 4 are arranged at intervals. Specifically, the dustproof MEMS module vibrates and produces sound under the action of air pressure in the sound cavity between the dustproof film 2 and the acoustic assembly. The vibration amplitude of the dustproof membrane 2 influences the volume of the sound cavity in the dustproof MEMS module. The volume of the sound cavity mainly influences the low-frequency characteristics of the dustproof MEMS module. For example, the dustproof film 2 and the waterproof film 4 are arranged at intervals, the dustproof film 2 has enough vibration space, and the volume of the sound cavity is increased continuously, so that the low-frequency characteristic of the dustproof MEMS module is improved.

In one embodiment, referring to fig. 2 and 3, an isolation film 6 is disposed between the dustproof film 2 and the waterproof film 4, one surface of the isolation film 6 is fixedly connected to the second surface of the dustproof film 2, and the other surface of the isolation film 6 is fixedly connected to the waterproof film 4.

Specifically, the separation film 6 is provided between the dustproof film 2 and the waterproof film 4, so that the dustproof film 2 and the waterproof film 4 are provided at an interval. Specifically, the isolation films 6 are located at both end edge regions of the dustproof film 2 and the waterproof film 4, so that the dustproof film 2 disposed opposite to the through hole 13 can generate vibration in a certain space to improve the low-frequency characteristics of the dustproof MEMS module.

One surface of the separation film 6 and the second surface of the dust-proof film 2 are fixedly connected by a first adhesive 61. One surface of the separation film 6 and the surface of the waterproof film 4 are fixedly connected by a second adhesive 62. For example, the first adhesive 61 and the second adhesive 62 may be hot melt adhesive tapes.

Further, as shown in fig. 2 and 3, the thickness of the separation film 6 ranges from 45 μm to 55 μm.

In other words, the distance between the second surface of the dustproof film 2 and the waterproof film 4 ranges from 45 μm to 55 μm regardless of the thickness of the first adhesive 61 and the thickness of the second adhesive 62. The vibration pitch of the dustproof film 2 vibrating in the direction approaching the waterproof film 4 is 45-55 μm. Alternatively, the thickness of the separation film 6 ranges from 50 μm.

The thickness of the isolation film 6 is controlled within the range, and the acoustic performance of the dustproof MEMS module can be improved under the condition that the overall height of the dustproof MEMS module is not influenced. For example, the present embodiment controls the thickness of the separation film 6 within this range, and the surface of the waterproof film 4 away from the dustproof film 2 is disposed flush with the second surface 12 of the circuit board 1, or the surface of the waterproof film 4 away from the dustproof film 2 is lower than the second surface 12 of the circuit board 1. This makes the dustproof film 2 not only have a dustproof effect but also protect the waterproof film 4 from external damage.

In one embodiment, referring to fig. 4, a conductive layer 7 is disposed on the second surface of the dustproof film 2, and the first surface of the dustproof film 2 and the second surface of the dustproof film 2 are disposed opposite to each other.

Specifically, the conductive layer 7 is coated on the second surface of the dustproof film 2, and the conductive layer 7 covers the second surface of the dustproof film 2. The dustproof MEMS module has the electromagnetic interference shielding function. The material of the conductive layer 7 includes metal or alloy. In the application of the dustproof MEMS module to an electronic device, the conductive layer 7 coated on the second surface of the dustproof film 2 is grounded.

In one embodiment, referring to fig. 1-2, the dustproof film 2 is made of metal.

Specifically, referring to fig. 1 and 2, the dust-proof film 2 is made of a metal material. For example, a thin metal sheet is used to manufacture a plurality of small holes corresponding to the through holes 13 on the circuit board 1 through corrosion, laser drilling and other processes, so that the performance of the circuit board in a complex external environment such as high temperature resistance can be better achieved, and a certain electromagnetic interference shielding function can be achieved.

In the case where the dust-proof film 2 is made of a metal material, the first surface of the dust-proof film 2 may be directly welded to the connection portion 142 provided on the bottom surface 141 of the recess groove 14. On the one hand, the connection strength of the dustproof film 2 and the circuit board 1 is improved. On the other hand, the dustproof film 2 made of the metal material can improve the electromagnetic interference shielding function of the dustproof MEMS module.

Alternatively, when the dust-proof film 2 is made of a metal material, the metal layer 21 may be provided on the first surface of the dust-proof film 2, and the metal layer 21 may be welded to the connection portion 142 provided on the bottom surface 141 of the recess groove 14. On the one hand, the connection strength of the dustproof film 2 and the circuit board 1 is improved. On the other hand, the dustproof film 2 made of the metal material can improve the electromagnetic interference shielding function of the dustproof MEMS module.

It should be noted that, the dust-proof film 2 is made of a metal material or the conductive layer 7 is disposed on a surface of the dust-proof film 2 away from the circuit board 1 to improve the shielding effect of the microphone device, and the present disclosure is not limited thereto, and is also applicable to a pressure sensor, a vibration sensor, and other similar MEMS electronic devices.

In one embodiment, referring to fig. 4, a plurality of through holes 13 penetrating through the first surface 11 and the second surface 12 are formed on the circuit board 1, and the plurality of through holes 13 are arranged at intervals.

The consistency of whole vibrating diaphragm can be improved, the vibration performance of vibrating diaphragm is guaranteed, and the use performance and the service life of microphone are promoted.

On the other hand, the embodiment of the invention also provides a microphone device.

Referring to fig. 1, 2 and 4, the microphone device includes the microphone package structure as described above, and a MEMS microphone chip 8 and an ASIC chip 9; the circuit board 1 and the shell 3 enclose to form an accommodating cavity, and the MEMS microphone chip 8 and the ASIC chip 9 are arranged in the accommodating cavity. The MEMS microphone chip 8 and the ASIC chip 9 may be protected by the housing 3 and the circuit board 1.

The ASIC chip 9 is fixedly disposed on the circuit board 1 (for example, may be fixedly connected to the circuit board 1 by an adhesive) and electrically connected to a circuit layer in the circuit board 1, and a protective adhesive 10 is coated outside the ASIC chip 9. The protective adhesive 10 can protect the ASIC chip 9 from water, dust, and the like, so as to prolong the service life of the ASIC chip.

In another aspect, the present disclosure also provides an electronic device including the microphone apparatus as described above.

The electronic device may be a mobile phone, a notebook computer, a tablet computer, a VR device, an intelligent wearable device, and the like, which is not limited by the present disclosure.

In the above embodiments, the differences between the embodiments are described in emphasis, and different optimization features between the embodiments can be combined to form a better embodiment as long as the differences are not contradictory, and further description is omitted here in consideration of brevity of the text.

Although some specific embodiments of the present disclosure 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 present disclosure. 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 present disclosure. The scope of the present disclosure is defined by the appended claims.