CN114125675A

CN114125675A - MEMS device, microphone and electronic product

Info

Publication number: CN114125675A
Application number: CN202111574856.6A
Authority: CN
Inventors: 李颖
Original assignee: Goertek Microelectronics Inc
Current assignee: Goertek Microelectronics Inc
Priority date: 2021-12-21
Filing date: 2021-12-21
Publication date: 2022-03-01

Abstract

The application discloses MEMS device, microphone and electronic product, MEMS device includes: a first circuit board; the second circuit board and the first circuit board are oppositely arranged at intervals, the first circuit board is positioned above the second circuit board, and one of the first circuit board and the second circuit board is provided with an acoustic through hole; the shell is arranged between the first circuit board and the second circuit board, the shell is matched with the first circuit board and the second circuit board to define an accommodating cavity, and the acoustic through hole is communicated with the accommodating cavity; the MEMS chip is arranged on one of the first circuit board and the second circuit board and is positioned in the accommodating cavity; and the ASIC chip is arranged in the accommodating cavity and is arranged on the other one of the first circuit board and the second circuit board. The MEMS device can effectively reduce the overall size of the MEMS device, can realize random switching between a false Top type and a Bottom type, and meets different requirements of a client terminal.

Description

MEMS device, microphone and electronic product

Technical Field

The present invention relates to the field of micro electro mechanical systems, and more particularly, to a MEMS device, a microphone, and an electronic product having the MEMS device.

Background

The existing MEMS device generally has two structures, one is that a sound hole for receiving a sound signal enters from the Bottom of the MEMS device, and the sound hole and the bonding pad are disposed on the same circuit board, and this structure type is called a Bottom type. The other is that sound holes for receiving sound signals enter from the Top of the MEMS device, the sound holes and the bonding pads are respectively arranged and are not arranged on the same circuit board, and the structure type is called as a Top type.

However, in the MEMS device of the prior art, whether the Bottom type or the Top type, the MEMS chip and the ASIC chip are arranged side by side on one circuit board, resulting in a large overall size of the MEMS device. And MEMS devices of the Bottom and Top type can only be used in one type to make electrical connections to the customer end products.

Disclosure of Invention

An object of the present application is to provide a new technical solution for a MEMS device, which can at least solve the problems in the prior art that the overall size of the MEMS device is large, and the Bottom-type and Top-type structures cannot be switched arbitrarily.

According to a first aspect of the present application, there is provided a MEMS device comprising: a first circuit board; the second circuit board and the first circuit board are arranged oppositely at intervals, the first circuit board is positioned above the second circuit board, and one of the first circuit board and the second circuit board is provided with an acoustic through hole; the shell is arranged between the first circuit board and the second circuit board, the shell is matched with the first circuit board and the second circuit board to define an accommodating cavity, and the acoustic through hole is communicated with the accommodating cavity; the MEMS chip is arranged on one of the first circuit board and the second circuit board and is positioned in the accommodating cavity; the ASIC chip is positioned in the containing cavity and is arranged on the other one of the first circuit board and the second circuit board.

Optionally, the MEMS chip is disposed on the first circuit board, the ASIC chip is disposed on the second circuit board, the acoustic through hole is disposed on the first circuit board, and the acoustic through hole corresponds to the MEMS chip.

Optionally, the MEMS chip and the ASIC chip are electrically connected through a first metal lead, and the ASIC chip is electrically connected to the second circuit board through a second metal lead.

Optionally, the MEMS chip is disposed on the second circuit board, the ASIC chip is disposed on the first circuit board, the acoustic through hole is disposed on the second circuit board, and the acoustic through hole corresponds to the MEMS chip.

Optionally, the MEMS chip and the ASIC chip are electrically connected through a first metal lead, and the ASIC chip is electrically connected to the first circuit board through a second metal lead.

Optionally, the MEMS chip is disposed directly opposite the ASIC chip.

Optionally, the MEMS chip is attached to one of the first circuit board and the second circuit board, and the ASIC chip is attached to the other of the first circuit board and the second circuit board.

Optionally, the housing is respectively connected to the first circuit board and the second circuit board by welding.

According to a second aspect of the present application, there is provided a microphone comprising the MEMS device described in the above embodiments.

According to a third aspect of the present application, there is provided an electronic product comprising the MEMS device described in the above embodiments.

According to the MEMS device provided by the embodiment of the invention, the first circuit board and the second circuit board which are oppositely arranged are arranged, the MEMS chip is arranged on one of the first circuit board and the second circuit board, and the ASIC chip is arranged on the other one of the first circuit board and the second circuit board, so that the overall size of the MEMS device is effectively reduced, meanwhile, the random switching between a false Top type and a Bottom type can be realized, and different requirements of a client terminal are met.

Further features of the present application and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which is to be read in connection with the accompanying drawings.

Drawings

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

FIG. 1 is a schematic diagram of a MEMS device in accordance with an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a MEMS device of an embodiment of the invention;

FIG. 3 is another schematic structural view of a MEMS device of an embodiment of the present invention;

FIG. 4 is a schematic diagram of yet another configuration of a MEMS device in accordance with an embodiment of the invention;

FIG. 5 is another cross-sectional view of a MEMS device of an embodiment of the invention.

Reference numerals:

a MEMS device 100;

a first wiring board 10;

a second wiring board 20;

a housing 30;

a MEMS chip 40;

an ASIC chip 50;

an acoustic via 60;

a first metal lead 70;

a second metal lead 80.

Detailed Description

Various exemplary embodiments of the present application 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 application 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 application, 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.

The MEMS device 100 according to an embodiment of the present invention is described in detail below with reference to the drawings.

As shown in fig. 1 to 5, a MEMS device 100 according to an embodiment of the present invention includes a first wiring board 10, a second wiring board 20, a case 30, a MEMS chip 40, and an ASIC chip 50.

Specifically, the second wiring board 20 and the first wiring board 10 are arranged in a spaced-apart opposing relationship, the first wiring board 10 is located above the second wiring board 20, and one of the first wiring board 10 and the second wiring board 20 is provided with an acoustic through-hole 60. The casing 30 is arranged between the first circuit board 10 and the second circuit board 20, the casing 30 cooperates with the first circuit board 10 and the second circuit board 20 to define a containing cavity, and the acoustic through hole 60 is communicated with the containing cavity. The MEMS chip 40 is provided on one of the first wiring board 10 and the second wiring board 20, and the MEMS chip 40 is located in the accommodation chamber. The ASIC chip 50 is located in the accommodation chamber, and the ASIC chip 50 is provided on the other of the first wiring board 10 and the second wiring board 20.

In other words, referring to fig. 1 to 5, the MEMS device 100 according to the embodiment of the present invention is mainly composed of the first wiring board 10, the second wiring board 20, the case 30, the MEMS chip 40, and the ASIC chip 50. The MEMS device 100(Micro-Electro-Mechanical System, Micro Electro-Mechanical System) has the characteristics of small volume, good frequency response, noise ground, and the like, and is one of the essential devices of the mobile terminal. Wherein the second circuit board 20 and the first circuit board 10 are arranged in a spaced-apart and opposite manner, and the first circuit board 10 is located above the second circuit board 20. The first wiring board 10 serves as the top of the MEMS device 100 and the second wiring board 20 serves as the bottom of the MEMS. One of the first wiring board 10 and the second wiring board 20 is provided with an acoustic via 60. When the acoustic vias 60 are opened on the first wiring board 10, sound enters from the Top of the MEMS device 100, and this type of structure may be referred to as a pseudo-Top type (as shown in fig. 1 and 2). The pseudo-Top type is also used with sound coming from the Top of the MEMS device 100, but the acoustic vias 60 are open on the circuit board, as opposed to the conventional Top type structure. Whereas in the conventional Top type structure, the acoustic vias 60 are open at the Top of the housing. The pseudo-Top type has better acoustic performance than the MEMS device 100 of the normal Top type structure. Similarly, when the acoustic via 60 is opened on the second wiring board 20, sound enters from the Bottom of the MEMS device 100, and this type of structure is called a Bottom type (as shown in fig. 3 to 5).

The housing 30 is disposed between the first circuit board 10 and the second circuit board 20, and the housing 30 and the first circuit board 10 and the second circuit board 20 cooperate to form a housing chamber. Compared with the prior art, the top of the housing 30 is replaced by the first Circuit board 10, one of the MEMS chip 40 and the ASIC chip 50 is disposed on the first Circuit board 10, the other of the MEMS chip 40 and the ASIC chip 50 (ASIC) is disposed on the second Circuit board 20 at the bottom of the housing 30, and the MEMS chip 40 and the ASIC chip 50 are separately disposed, so as to effectively reduce the size of the MEMS device 100.

The acoustic vias 60 communicate with the receiving cavities in which the MEMS chip 40 and the ASIC chip 50 are located, respectively. The MEMS chip 40 is disposed on one of the first wiring board 10 and the second wiring board 20, and the ASIC chip 50 is disposed on the other of the first wiring board 10 and the second wiring board 20, thereby realizing arbitrary switching of the pseudo Top type and the Bottom type (as shown in fig. 2 and 5). The capacitance of the MEMS chip 40 will change correspondingly with the change of the incoming sound, and the ASIC chip 50 is used to process and output the changed capacitance signal, so as to pick up the sound.

It should be noted that the acoustic performance of the conventional Bottom-type device is generally superior to that of the conventional Top-type device. But ordinary Top-type devices are more convenient for electrical connection to the end product. In the MEMS device 100 of the present invention, the top surface of the housing 30 is replaced with the first wiring board 10, and the two wiring boards are designed, wherein the first wiring board 10 and the second wiring board 20 are arranged opposite to each other. When the pseudo Top type is required to be switched to the Bottom type, the upper position and the lower position of the MEMS device 100 are required to be turned by 180 degrees, the structure of the MEMS device 100 is not required to be improved, therefore, the pseudo Top type and the Bottom type can be switched randomly, double-sided welding can be realized, and different welding requirements of customers can be met.

In the present application, for convenience of describing the positional relationship of the MEMS device 100, regardless of the MEMS device 100 of the pseudo Top type or the Bottom type structure, the circuit board located at the Top of the case 30 is collectively referred to as the first circuit board 10, and the circuit board located at the Bottom of the case 30 is collectively referred to as the second circuit board 20. The wiring board is called a Printed wiring board { Printed circuit boards }, or a Printed circuit board. The first circuit board 10 and the second circuit board 20 are only for convenience of description, and therefore, in the present application, the first circuit board 10 and the second circuit board 20 are switched arbitrarily, when the upper and lower positions of the MEMS device 100 are turned by 180 °, the first circuit board 10 before turning is the second circuit board 20 after turning, and the second circuit board 20 before turning is the first circuit board 10 after turning.

Therefore, according to the MEMS device 100 of the embodiment of the present invention, the first circuit board 10 and the second circuit board 20 are disposed oppositely, the MEMS chip 40 is disposed on one of the first circuit board 10 and the second circuit board 20, and the ASIC chip 50 is disposed on the other of the first circuit board 10 and the second circuit board 20, so as to effectively reduce the overall size of the MEMS device 100, and simultaneously, the arbitrary switching between the pseudo Top type and the Bottom type can be realized, and different welding requirements of the client terminal can be met.

According to an embodiment of the present invention, the MEMS chip 40 is provided on the first wiring board 10, the ASIC chip 50 is provided on the second wiring board 20, the acoustic via 60 is provided on the first wiring board 10, and the acoustic via 60 corresponds to the MEMS chip 40.

That is, referring to fig. 1 and 2, the MEMS chip 40 is disposed on the first circuit board 10 at the top of the housing 30, the ASIC chip 50 is disposed on the second circuit board 20 at the bottom of the housing 30, and the MEMS chip 40 and the ASIC chip 50 do not need to be disposed side by side on a circuit board at the same time, which effectively reduces the structural size of the MEMS device 100 and meets the requirement of device miniaturization. Meanwhile, different welding requirements of the client terminal can be met by arranging the first circuit board 10 and the second circuit board 20 which are oppositely arranged. The acoustic via 60 is provided on the first wiring board 10 on the top of the case 30, and the acoustic via 60 faces the MEMS chip 40. In this case, the MEMS device 100 is a pseudo Top structure, which corresponds to the opening of the acoustic via 60 in the Top of the case 30. External environmental sounds are introduced into the MEMS device 100 through the acoustic through-hole 60 of the top first wiring board 10, and the MEMS chip 40 induces sound waves in the receiving cavity and stably converts the induced sound waves into electrical signals. The capacitance of the MEMS chip 40 will change correspondingly with the difference of the input sound signal, and then the ASIC chip 50 is used to process the changed capacitance signal and output it to the circuit board, thereby realizing the sound pickup.

According to an embodiment of the present invention, the MEMS chip 40 and the ASIC chip 50 are electrically connected through a first metal wire 70, and the ASIC chip 50 is electrically connected through a second metal wire 80 and the second wiring board 20.

In other words, as shown in fig. 1 and 2, for the pseudo-Top type MEMS device 100, the MEMS chip 40 on the first wiring board 10 on the Top of the housing 30 is electrically connected to the ASIC chip 50 on the second wiring board 20 on the bottom of the housing 30 through the first metal lead 70, so that the MEMS chip 40 transmits the acoustic wave signal to the ASIC chip 50. The ASIC chip 50 on the second circuit board 20 at the bottom of the housing 30 is connected to the second circuit board 20 through the second metal lead 80, so that the ASIC chip 50 processes the signal transmitted by the MEMS chip 40 and outputs the processed signal to the second circuit board 20, thereby picking up sound.

According to an embodiment of the present invention, the MEMS chip 40 is provided on the second wiring board 20, the ASIC chip 50 is provided on the first wiring board 10, the acoustic via 60 is provided on the second wiring board 20, and the acoustic via 60 corresponds to the MEMS chip 40.

That is, referring to fig. 3 to 5, the MEMS chip 40 is disposed on the second circuit board 20 at the top of the housing 30, the ASIC chip 50 is disposed on the first circuit board 10 at the bottom of the housing 30, and the MEMS chip 40 and the ASIC chip 50 do not need to be disposed side by side on a circuit board at the same time, which effectively reduces the structural size of the MEMS device 100 and meets the requirement of device miniaturization. Meanwhile, different welding requirements of the client terminal can be met by arranging the first circuit board 10 and the second circuit board 20 which are oppositely arranged. The acoustic via 60 is provided on the second wiring board 20 at the bottom of the case 30, and the acoustic via 60 faces the MEMS chip 40. At this time, the MEMS device 100 is a Bottom type structure, which is equivalent to the common MEMS device 100 that an acoustic through hole 60 is opened on a circuit board at the Bottom of the housing 30. External environmental sounds are introduced into the MEMS device 100 through the acoustic through-holes 60 on the bottom second wiring board 20, and the MEMS chip 40 induces acoustic waves in the receiving cavity and stably converts the induced acoustic waves into electrical signals. The capacitance of the MEMS chip 40 will change correspondingly with the difference of the input sound signal, and then the ASIC chip 50 is used to process the changed capacitance signal and output it to the circuit board, thereby realizing the sound pickup.

Therefore, the overall structures of the pseudo Top type device and the Bottom type device are not changed, and the pseudo Top type device and the Bottom type device can be welded on two sides. The whole device can be switched between the pseudo Top type and the Bottom type at will only by turning the whole device 180 degrees, and different welding requirements of a client terminal are met.

According to an embodiment of the present invention, the MEMS chip 40 and the ASIC chip 50 are electrically connected through a first metal wire 70, and the ASIC chip 50 is electrically connected through a second metal wire 80 to the first wiring board 10.

In other words, as shown in fig. 3 to 5, for the Bottom-type MEMS device 100, the MEMS chip 40 on the second wiring board 20 at the Bottom of the case 30 is electrically connected to the ASIC chip 50 on the first wiring board 10 at the top of the case 30 through the first metal lead 70, so that the MEMS chip 40 transmits the acoustic wave signal to the ASIC chip 50. The ASIC chip 50 on the first circuit board 10 on the top of the housing 30 is connected to the second circuit board 20 through the second metal lead 80, so that the ASIC chip 50 processes the signal transmitted by the MEMS chip 40 and outputs the processed signal to the second circuit board 20, thereby picking up sound.

Alternatively, referring to fig. 2 and 5, the MEMS chip 40 is disposed directly opposite the ASIC chip 50. That is to say, in the MEMS device 100 of the present invention, the two circuit boards (the first circuit board 10 and the second circuit board 20) are oppositely disposed, the MEMS chip 40 and the ASIC chip 50 are respectively disposed on one circuit board, and the MEMS chip 40 and the ASIC chip 50 are disposed opposite to each other, so as to reduce the structural size of the MEMS device 100 to the maximum extent, and ensure the excellent acoustic performance of the MEMS device 100, facilitate the arbitrary switching between the pseudo Top type and the Bottom type, and meet different welding requirements of the client terminal. .

According to one embodiment of the present invention, the MEMS chip 40 is adhesively connected to one of the first wiring board 10 and the second wiring board 20, and the ASIC chip 50 is adhesively connected to the other of the first wiring board 10 and the second wiring board 20. The case 30 is solder-connected to the first circuit board 10 and the second circuit board 20, respectively.

In other words, the top surface of the case 30 is replaced with one wiring board (the first wiring board 10), and one of the two wiring boards (the first wiring board 10 and the second wiring board 20) on the top surface and the bottom surface of the case 30 may mount the MEMS chip 40 and the other mount the ASIC chip 50. And in the mounting process, the MEMS chip 40 and the ASIC chip 50 are electrically connected through a first metal lead 70, and the ASIC chip 50 and the corresponding circuit board are electrically connected through a second metal lead 80. Wherein, an acoustic through hole 60 facing the MEMS chip 40 is formed on a circuit board on which the MEMS chip 40 is mounted, which is beneficial to improving the sensitivity of the MEMS device 100.

Four sides of the housing 30 are located between the first circuit board 10 and the second circuit board 20, and the four sides are respectively connected with the first circuit board 10 and the second circuit board 20 by welding, so that the stability of the whole structure of the MEMS device 100 is improved. In the actual routing process, three sides of the housing 30 can be welded on four sides, and the fourth side is welded after routing (for example, the first metal lead 70 and the second metal lead 80) is completed, so that the operation is simple and convenient, and the manufacturing is easy.

In summary, according to the MEMS device 100 of the embodiment of the present invention, the first circuit board 10 and the second circuit board 20 are disposed oppositely, the MEMS chip 40 is disposed on one of the first circuit board 10 and the second circuit board 20, and the ASIC chip 50 is disposed on the other of the first circuit board 10 and the second circuit board 20, so that the overall size of the MEMS device 100 is effectively reduced, and at the same time, arbitrary switching between the pseudo Top type and the Bottom type can be realized, and different soldering requirements of the client terminal can be met.

According to a second aspect of the present application, a microphone is provided, comprising the MEMS device 100 of the above embodiments. Since the MEMS device 100 according to the embodiment of the present invention has the above technical effects, the microphone according to the embodiment of the present invention should also have corresponding technical effects, that is, the microphone according to the present application adopts the MEMS device 100 according to the embodiment, so that the overall size of the microphone can be effectively reduced, and meanwhile, the arbitrary switching between the pseudo Top type and the Bottom type can be realized, thereby satisfying different welding requirements of the client terminal. The microphone is a small-sized pseudo Top/Bottom type microphone that can be soldered on both sides.

According to a third aspect of the present application, an electronic product is provided, comprising the MEMS device 100 of the above embodiments. The electronic product of the present application includes a complete machine housing and the MEMS device 100 of the above embodiment disposed in the complete machine housing. The electronic product may be a product with the MEMS device 100, such as a mobile phone, a tablet computer, or a headset.

Since the MEMS device 100 according to the embodiment of the present invention has the above technical effects, the electronic product according to the present invention should also have corresponding technical effects, that is, the electronic product according to the present application adopts the MEMS device 100 according to the embodiment, so that the overall size of the microphone can be effectively reduced, and meanwhile, the arbitrary switching between the pseudo Top type and the Bottom type can be realized, thereby satisfying different welding requirements of the client terminal.

Of course, the working principles and other structures of the MEMS device 100, the microphone and the electronic product of the present application are understood and can be implemented by those skilled in the art, and will not be described in detail in the present application.

Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present application. 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 application. The scope of the application is defined by the appended claims.

Claims

1. A MEMS device, comprising:

a first circuit board;

the second circuit board and the first circuit board are arranged oppositely at intervals, the first circuit board is positioned above the second circuit board, and one of the first circuit board and the second circuit board is provided with an acoustic through hole;

the shell is arranged between the first circuit board and the second circuit board, the shell is matched with the first circuit board and the second circuit board to define an accommodating cavity, and the acoustic through hole is communicated with the accommodating cavity;

the MEMS chip is arranged on one of the first circuit board and the second circuit board and is positioned in the accommodating cavity;

the ASIC chip is positioned in the containing cavity and is arranged on the other one of the first circuit board and the second circuit board.

2. The MEMS device, as recited in claim 1, wherein the MEMS chip is disposed on the first circuit board, the ASIC chip is disposed on the second circuit board, the acoustic via is disposed on the first circuit board, and the acoustic via corresponds to the MEMS chip.

3. The MEMS device, as recited in claim 2, wherein the MEMS chip and the ASIC chip are electrically connected by a first metal lead, and the ASIC chip is electrically connected to the second wiring board by a second metal lead.

4. The MEMS device, as recited in claim 1, wherein the MEMS chip is disposed on the second circuit board, the ASIC chip is disposed on the first circuit board, the acoustic via is disposed on the second circuit board, and the acoustic via corresponds to the MEMS chip.

5. The MEMS device of claim 4, wherein the MEMS chip and the ASIC chip are electrically connected by a first metal lead, and the ASIC chip is electrically connected to the first wiring board by a second metal lead.

6. The MEMS device, as recited in claim 1, wherein the MEMS chip is disposed directly opposite the ASIC chip.

7. The MEMS device, as recited in claim 1, wherein the MEMS chip is adhesively attached to one of the first and second circuit boards, and the ASIC chip is adhesively attached to the other of the first and second circuit boards.

8. The MEMS device, as recited in claim 1, wherein the housing is solder bonded to the first and second circuit boards, respectively.

9. A microphone comprising a MEMS device as claimed in any one of claims 1 to 8.

10. An electronic product comprising a MEMS device according to any one of claims 1 to 8.