阅读说明：本技术 Mems麦克风封装结构及封装方法 (MEMS microphone packaging structure and packaging method ) 是由 于强 于 2021-08-27 设计创作，主要内容包括：本发明提供一种MEMS麦克风封装结构及封装方法,其中的MEMS麦克风封装结构包括：主板、设置在主板上的待封装MEMS麦克风；其中,在主板上设置有与待封装MEMS麦克风相适配的镂空槽；待封装MEMS麦克风嵌设在镂空槽内,并与主板焊接导通。利用上述发明能够节省MEMS麦克风的占用空间,减小声音传输通道的长度,提高MEMS麦克风的声学性能。(The invention provides an MEMS microphone packaging structure and a packaging method, wherein the MEMS microphone packaging structure comprises: the MEMS microphone comprises a mainboard and an MEMS microphone to be packaged, wherein the MEMS microphone is arranged on the mainboard; wherein, a hollow groove matched with the MEMS microphone to be packaged is arranged on the mainboard; the MEMS microphone to be packaged is embedded in the hollow groove and is welded and conducted with the mainboard. The invention can save the occupied space of the MEMS microphone, reduce the length of the sound transmission channel and improve the acoustic performance of the MEMS microphone.)

1. A MEMS microphone package structure, comprising: the MEMS microphone comprises a mainboard and an MEMS microphone to be packaged, wherein the MEMS microphone is arranged on the mainboard; wherein the content of the first and second substances,

a hollow groove matched with the MEMS microphone to be packaged is formed in the main board;

the MEMS microphone to be packaged is embedded in the hollow groove and is welded and conducted with the mainboard.

2. The MEMS microphone package structure of claim 1,

a welding disc groove is formed in the peripheral side wall of the hollow groove;

and the side wall of the MEMS microphone to be packaged is welded and communicated with the welding disc groove through soldering tin.

3. The MEMS microphone package structure of claim 2,

the pad groove penetrates through the main board in the thickness direction of the main board; or the welding disc groove is arranged on the upper end face and/or the lower end face of the main board at the position of the hollow groove.

4. The MEMS microphone package structure of claim 2,

the cross section of the welding disk groove is arc-shaped, wave-shaped or regular and multi-deformation.

5. The MEMS microphone package structure of claim 2,

the MEMS microphone to be packaged comprises a PCB, a shell forming a packaging structure with the PCB, and a chip arranged between the PCB and the shell;

side bonding pads corresponding to the bonding pad grooves are arranged on the periphery of the PCB;

and the pad groove is welded and conducted with the side pad.

6. The MEMS microphone package structure of claim 5,

the number of the side bonding pads is consistent with the number of the output signals of the MEMS microphone to be packaged.

7. The MEMS microphone package structure of claim 5,

the cross section of the side bonding pad is arc-shaped, wave-shaped or regular and multi-deformation.

8. The MEMS microphone package structure of claim 1,

when the hollow groove is of a cuboid structure, four corner positions of the hollow groove are respectively provided with chamfers with arc-shaped cross sections.

9. The MEMS microphone package structure of claim 1,

the shape of the hollow groove is matched with that of the MEMS microphone to be packaged; and the number of the first and second electrodes,

the opening size of the hollow groove is not smaller than the size of the MEMS microphone to be packaged.

10. A MEMS microphone packaging method to form a MEMS microphone packaging structure as claimed in any one of claims 1 to 9; characterized in that the method comprises:

the method comprises the following steps that a hollow groove is formed in a main board, a pad groove is formed in the side wall of the hollow groove, and a side pad corresponding to the pad groove is arranged on a PCB of the MEMS microphone to be packaged;

placing the MEMS microphone to be packaged in the hollow groove, and filling solder paste between the pad groove and the side bonding pad;

and assembling the MEMS microphone to be packaged on the mainboard through reflow soldering.

Technical Field

The invention relates to the technical field of product packaging, in particular to an MEMS microphone packaging structure and a packaging method.

Background

With the progress of society and the development of technology, in recent years, the volume of electronic products such as mobile phones and notebook computers is continuously reduced, and people have higher and higher performance requirements on the portable electronic products, so that the volume of electronic parts matched with the portable electronic products is continuously reduced, and the performance and consistency are continuously improved. MEMS microphones integrated by MEMS (Micro-Electro-Mechanical-System, abbreviated as MEMS) technology are beginning to be applied to electronic products such as mobile phones and notebook computers in batches, and the package volume thereof is smaller than that of the conventional electret microphone, so that the MEMS microphones are favored by most microphone manufacturers.

The existing MEMS packaging is generally to weld a bonding pad at the bottom of an MEMS microphone with a bonding pad on a mainboard by adopting an SIP packaging technology; however, since the main board has a certain thickness, the MEMS microphone is directly fixed on the main board, which increases the length of the sound transmission channel, and causes the resonant peak of the MEMS microphone to move forward and the MEMS microphone to warp upward at high frequency.

It is known that the existing MEMS microphone packaging structure is not only not good for the miniaturization development of the product, but also affects the acoustic performance of the microphone.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a MEMS microphone package structure and a packaging method thereof, so as to solve the problems that the existing packaging method is likely to result in a larger overall volume of the product and affect the acoustic performance of the microphone.

The invention provides an MEMS microphone packaging structure, comprising: the MEMS microphone comprises a mainboard and an MEMS microphone to be packaged, wherein the MEMS microphone is arranged on the mainboard; wherein, a hollow groove matched with the MEMS microphone to be packaged is arranged on the mainboard; the MEMS microphone to be packaged is embedded in the hollow groove and is welded and conducted with the mainboard.

In addition, the optional technical scheme is that a welding disc groove is formed in the peripheral side wall of the hollow groove; and the side wall of the MEMS microphone to be packaged is welded and conducted with the bonding pad groove through soldering tin.

In addition, an optional technical scheme is that the pad groove penetrates through the main board in the thickness direction of the main board; or the pad groove is arranged on the upper end surface and/or the lower end surface of the mainboard at the position of the hollow groove.

In addition, the optional technical scheme is that the cross section of the pad groove is arc-shaped, wave-shaped or regular and multi-deformation.

In addition, an optional technical solution is that the MEMS microphone to be packaged includes a PCB, a housing forming a package structure with the PCB, and a chip disposed between the PCB and the housing; side bonding pads corresponding to the bonding pad grooves are arranged on the periphery of the PCB; and the pad groove is welded and conducted with the side pad.

In addition, an optional technical scheme is that the number of the side bonding pads is consistent with the number of output signals of the MEMS microphone to be packaged.

In addition, the optional technical scheme is that the cross section of the side bonding pad is arc-shaped, wave-shaped or regular and multi-deformation.

In addition, an optional technical scheme is that when the hollow groove is of a cuboid structure, chamfers with arc-shaped cross sections are respectively arranged at four corner positions of the hollow groove.

In addition, an optional technical scheme is that the shape of the hollow groove is matched with the shape of the MEMS microphone to be packaged; and the opening size of the hollow groove is not smaller than the size of the MEMS microphone to be packaged.

According to another aspect of the present invention, a method for packaging a MEMS microphone is provided to form the above-mentioned MEMS microphone packaging structure; the method comprises the following steps: the method comprises the following steps that a hollow groove is formed in a main board, a pad groove is formed in the side wall of the hollow groove, and a side pad corresponding to the pad groove is arranged on a PCB of the MEMS microphone to be packaged; placing the MEMS microphone to be packaged in the hollow groove, and filling solder paste between the pad groove and the side bonding pad; and assembling the MEMS microphone to be packaged on the mainboard through reflow soldering.

By utilizing the MEMS microphone packaging structure and the packaging method, the hollow groove matched with the MEMS microphone to be packaged is formed in the mainboard, the MEMS microphone to be packaged is embedded in the hollow groove and is welded and conducted with the mainboard, the structure not only can save the space occupied by the MEMS microphone on the mainboard, but also can shorten the channel length of sound in the transmission process, and can prevent the problems of forward movement of the resonance peak of the MEMS microphone, high-frequency upwarping and the like, so that the product acoustic performance can be improved, and the miniaturization development of products is facilitated.

To the accomplishment of the foregoing and related ends, one or more aspects of the invention comprise the features hereinafter fully described. The following description and the annexed drawings set forth in detail certain illustrative aspects of the invention. These aspects are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Further, the present invention is intended to include all such aspects and their equivalents.

Drawings

Other objects and results of the present invention will become more apparent and more readily appreciated as the same becomes better understood by reference to the following description taken in conjunction with the accompanying drawings. In the drawings:

FIG. 1 is a first schematic diagram illustrating a first partial structure of a MEMS microphone package structure according to an embodiment of the present invention;

FIG. 2 is a second schematic diagram illustrating a partial structure of a MEMS microphone package structure according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a motherboard structure according to an embodiment of the invention;

FIG. 4 is a schematic diagram of a MEMS microphone structure to be packaged according to the present invention;

fig. 5 is a flowchart of a MEMS microphone packaging method according to an embodiment of the invention.

Wherein the reference numerals include: mainboard 1, MEMS microphone 2 of waiting to encapsulate, fretwork groove 3, pad groove 4, chamfer 5, side pad 6, shell 7, PCB 8.

The same reference numbers in all figures indicate similar or corresponding features or functions.

Detailed Description

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

In order to describe the MEMS microphone packaging structure and the packaging method of the present invention in detail, embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 and 2 show partial structures of a MEMS microphone package structure according to an embodiment of the present invention from upper and lower angles, respectively.

As shown in fig. 1 and fig. 2, the MEMS microphone packaging structure of the embodiment of the present invention includes a main board 1 and a MEMS microphone 2 to be packaged, which is disposed on the main board 1; in order to reduce the acoustic influence of the thickness of the mainboard 1 on the MEMS microphone, a hollow groove matched with the MEMS microphone 2 to be packaged is formed in the mainboard 1, the MEMS microphone 2 to be packaged is embedded in the hollow groove and is welded and conducted with the mainboard 1, and a sound signal emitted by the MEMS microphone can be directly transmitted without passing through the thickness of the mainboard 1, so that the length of a sound transmission channel can be effectively reduced, and the acoustic performance of a product is improved; in addition, the MEMS microphone is arranged inside the mainboard 1, so that the space of the mainboard 1 can be saved, and the miniaturization development of products is facilitated.

Specifically, fig. 3 shows a schematic structure of a main board according to an embodiment of the present invention.

As shown in fig. 3, the main board 1 of the embodiment of the present invention is a rectangular structure, and the main board 1 can also be understood as a main board 1 PCB; the main board 1 is provided with a hollow groove 3 matched with the shape of the MEMS microphone to be packaged, the side walls of the periphery of the hollow groove 3 are provided with a plurality of pad grooves 4, the MEMS microphone to be packaged is embedded in the hollow groove 3, and the side wall of the MEMS microphone to be packaged and the pad grooves 4 can be welded, fixed and conducted through soldering tin.

In the thickness direction along the main board 1, the pad grooves 4 may be disposed through the main board 1 to form a groove-shaped structure extending through the thickness direction of the whole main board 1, or disposed on both sides of the main board 1, for example, the pad grooves 4 are disposed on the upper end surface and/or the lower end surface of the main board where the hollow grooves 3 are located, so as to form a groove-shaped structure disposed only on the main board in a dotted distribution, that is, the pad grooves 4 on the upper end surface and the lower end surface of the main board are not connected.

In an embodiment of the present invention, the cross section of the pad groove 4 is in various shapes such as arc, wave or regular multiple deformation, and the cross section herein mainly refers to a cross section along the extending direction of the motherboard 1 (the same below), and the MEMS microphone to be packaged can be fixed in the hollow groove by welding through the arrangement of the pad groove 4, so the arrangement number, the arrangement position, the shape, and the like of the pad groove 4 can be flexibly adjusted according to the requirement of the MEMS microphone to be packaged, and is not limited to the specific structure shown in the drawings.

In addition, in order to facilitate the processing of the main board 1, when the hollow groove 3 is of a cuboid structure, the cross section of the chamfer 5 is arc-shaped at four corner positions of the hollow groove 3 in decibel, the chamfer 5 can simplify the processing of the hollow groove 3 on the main board 1, and can offset the stress generated in the processing and packaging processes of the main board 1, so that the processing of the main board 1 and the installation of the MEMS microphone to be packaged are facilitated.

Therefore, in the processing process of the main board 1, the shape of the hollow groove should be matched with the shape of the MEMS microphone to be packaged; moreover, the size of the opening of the hollow groove is not smaller than the size of the MEMS microphone to be packaged, and the opening size can be set to be slightly larger than the size of the MEMS microphone.

In particular, fig. 4 shows a schematic structure of a MEMS microphone to be packaged implemented according to the present invention.

As shown in fig. 4, the MEMS microphone to be packaged according to the embodiment of the present invention includes a PCB8, a case 7 forming a package structure with the PCB8, and a chip accommodated between the PCB8 and the case 7; the size of the PCB is slightly larger than that of the shell 7, so that the side bonding pads 6 corresponding to the bonding pad groove positions can be arranged on the periphery of the PCB8, and in the packaging process, the bonding pad groove is welded with the side bonding pads 6, so that the conduction between the MEMS microphone and the mainboard is realized.

In one embodiment of the present invention, the cross section of the side pad 6 may be configured as an arc, a wave, a regular polygon, or the like; in addition, the specific number of the side pads 6 is consistent with the number of the output signals of the MEMS microphone to be packaged, and can be set according to the type of the product or the requirement.

Corresponding to the MEMS microphone packaging structure, the invention also provides an MEMS microphone packaging method.

In particular, fig. 5 shows a flow of a MEMS microphone packaging method according to an embodiment of the present invention.

As shown in fig. 5, the method for packaging an MEMS microphone according to the embodiment of the present invention mainly includes:

s110: the method comprises the following steps that a hollow groove is formed in a main board, a pad groove is formed in the side wall of the hollow groove, and a side pad corresponding to the pad groove is arranged on a PCB of the MEMS microphone to be packaged;

s120: placing the MEMS microphone to be packaged in the hollow groove, and filling solder paste between the pad groove and the side pad

S130: and assembling the MEMS microphone to be packaged on the mainboard through reflow soldering.

It should be noted that, in the MEMS microphone packaging and packaging method of the present invention, the size and shape of the opening of the pad slot and the side pad can be set according to the size and packaging requirements of the specific product, and according to the MEMS microphone packaging and packaging method of the present invention, the influence of the thickness of the main board on the microphone performance can be effectively reduced, and a flatter frequency response characteristic can be obtained; in addition, the microphone is embedded in the mainboard, so that the space of the mainboard can be saved, and the miniaturization development of products is facilitated.

The MEMS microphone package and the packaging method according to the present invention are described above by way of example with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that various modifications may be made to the MEMS microphone package and packaging method of the present invention without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should be determined by the contents of the appended claims.