CN219659911U - MEMS microphone - Google Patents

Abstract

The utility model provides a MEMS microphone, which includes a substrate with a back cavity and a capacitor system arranged on the substrate. The capacitor system includes a back plate and a diaphragm arranged opposite to the back plate. The membrane is located between the base and the back plate. The diaphragm is provided with a through hole. The back plate includes a body part, an extension column extending from the body part to the base and passing through the through hole; A gasket connected to the extension column, the gasket is located between the diaphragm and the base, one end of the extension column is connected to the body part of the back plate, and the other end is connected to the gasket . Compared with related technologies, the MEMS microphone provided by the present utility model can enhance the reliability of the product.

Description

MEMS microphone

【Technical field】

The utility model relates to the field of electroacoustic conversion, and in particular to a MEMS microphone.

【Background technique】

Mobile communication technology has developed rapidly in recent years, and consumers are increasingly using mobile communication devices, such as portable phones, Internet-enabled portable phones, personal digital assistants or other devices for communication in dedicated communication networks, among which microphones are among them. One of the important components, especially the MEMS microphone.

Micro-Electro-Mechanical System (MEMS) microphone is an electric energy sound exchanger made using micromachining technology. It has the characteristics of small size, good frequency response characteristics, and low noise. With the development of compact, thin and light electronic devices, MEMS microphones are more and more widely used in these devices.

MEMS microphones in the related art include a substrate with a back cavity and a capacitor system disposed on the substrate. The capacitor system includes a back plate and a diaphragm arranged opposite to the back plate. The diaphragm is located on the side of the backplate close to the substrate. During the vibration process of the diaphragm, especially when it is hit hard, the diaphragm will come into contact with the edge of the substrate, thereby reducing the strength and reliability of the MEMS.

Therefore, it is necessary to provide an improved MEMS microphone to solve the above problems.

【Utility model content】

The technical problem to be solved by this utility model is to provide a MEMS microphone with high reliability.

In order to solve the above technical problems, a MEMS microphone is provided, which includes a substrate with a back cavity and a capacitor system arranged on the substrate. The capacitor system includes a back plate and a diaphragm arranged opposite to the back plate. The diaphragm is located between the base and the back plate, and the diaphragm is provided with a through hole. The back plate includes a body part, and a ring extending from the body part to the base and passing through the through hole. An extension column and a gasket connected to the extension column, the gasket is located between the diaphragm and the base, one end of the extension column is connected to the body part of the back plate, and the other end is connected to the Gasket connection.

Preferably, the projection of the gasket along the vibration direction of the diaphragm is at least partially located on the base.

Preferably, the width of the gasket is greater than the width of the extension column.

Preferably, the width of the gasket is larger than the diameter of the through hole.

Preferably, the extension column and the body part are an integral structure.

Preferably, the gasket is an insulating gasket.

Preferably, the extension column and gasket are hollow annular structures.

Compared with related technologies, by arranging a gasket connected to the main body of the back plate between the diaphragm and the base, direct contact between the diaphragm and the edge of the base is avoided, thereby enhancing the strength of the diaphragm and improving product reliability.

[Picture description]

In order to explain the technical solutions in the embodiments of the present utility model more clearly, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some implementations of the utility model. For example, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts, among which:

Figure 1 is a cross-sectional view of the MEMS microphone provided by the present utility model.

【Detailed ways】

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some of the embodiments of the present utility model, not all of them. Example. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present utility model.

Please refer to FIG. 1 , which is a MEMS microphone 100 of the present invention, which includes a substrate 11 with a back cavity 10 and a capacitor system 20 disposed on the substrate 11 . The capacitive system 20 includes a back plate 21 and a diaphragm 22 disposed opposite to the back plate 21 . The diaphragm 22 is located on a side of the back plate 21 close to the substrate 11 . When sound pressure acts on the diaphragm 22, there is a pressure difference between the two sides of the diaphragm 22 facing the back plate 21 and facing away from the back plate 21, causing the diaphragm 22 to move closer to the back plate 21 or away from the back plate 21, thereby causing the diaphragm 22 to move closer to the back plate 21 or farther away from the back plate 21. The change in capacitance between the backplane 21 and the backplane 21 realizes the conversion of sound signals into electrical signals.

The diaphragm 22 is provided with a through hole 220 , and the through hole 220 can be used to adjust the damping of the diaphragm 22 . The back plate 21 includes a body part 211, an extension column 212 extending from the body part 211 to the base 11 and penetrating the through hole 220, and a gasket 213 connected to the extension column 212. The body part 211 is provided with There are a plurality of back plate holes 210. One end of the extension column 212 is connected to the body part 211 of the back plate 21, and the other end is connected to the gasket 213. In addition, the gasket 213 is located between the diaphragm 22 and the between base 11.

In this embodiment, the projection of the spacer 213 along the vibration direction of the diaphragm 22 is at least partially located on the base 11 . When the diaphragm 22 is working under sound pressure, the diaphragm 22 moves upward, and the design of the back plate 21 does not affect the degree of freedom of the diaphragm 22, so that the sensitivity of the diaphragm 22 is not lost; when the MEMS microphone 100 is dropped or When being hit hard, the gasket 213 of the back plate 21 will protect the diaphragm 22 so that the diaphragm 22 is not in direct contact with the edge of the base 11 , thereby strengthening the diaphragm 22 and mitigating the impact on the diaphragm 22 when the diaphragm 22 contacts the base 11 of damage.

Specifically, the width of the gasket 213 is larger than the width of the extension post 212 and the aperture of the through hole 220, so that when the amplitude of the diaphragm 22 is too large, the diaphragm 22 contacts the gasket 213, or the gasket 213 contacts the base 11. It plays the role of protecting the diaphragm 22.

The extension pillar 212 may be an integral structure with the body part 211, that is, the nitride backplane is directly deposited, and the gasket 213 is made of insulating material. In addition, in this embodiment, the extension column 212 and the gasket 213 are hollow annular structures. In other embodiments, the extension column and the gasket can also be several independent structures.

Compared with the related technology, by disposing the gasket 213 connected to the body part 211 of the back plate 21 between the diaphragm 22 and the base 11, direct contact between the diaphragm 22 and the edge of the base 11 is avoided, and the strength of the diaphragm 22 is enhanced, and It can improve product reliability.

The above are only embodiments of the present utility model. It should be pointed out that for those of ordinary skill in the art, improvements can be made without departing from the creative concept of the present utility model, but these are all protection scope of this utility model.

Claims (7)

1. The MEMS microphone comprises a substrate with a back cavity and a capacitance system arranged on the substrate, wherein the capacitance system comprises a back plate and a vibrating diaphragm which is arranged opposite to the back plate, the vibrating diaphragm is positioned between the substrate and the back plate, and the MEMS microphone is characterized in that the vibrating diaphragm is provided with a through hole, the back plate comprises a body part, an extension column which extends from the body part to the substrate and penetrates through the through hole, and a gasket connected with the extension column, the gasket is positioned between the vibrating diaphragm and the substrate, one end of the extension column is connected with the body part of the back plate, and the other end of the extension column is connected with the gasket.

2. The MEMS microphone of claim 1, wherein: the projection of the gasket along the vibration direction of the vibrating diaphragm is at least partially positioned on the substrate.

3. The MEMS microphone of claim 1, wherein: the width of the gasket is greater than the width of the extension post.

4. The MEMS microphone of claim 1, wherein: the width of the gasket is larger than the aperture of the through hole.

5. The MEMS microphone of claim 1, wherein: the extension column and the body part are of an integrated structure.

6. The MEMS microphone of claim 1, wherein: the gasket is an insulating gasket.

7. The MEMS microphone of claim 1, wherein: the extending column and the gasket are of hollow annular structures.