WO2021088241A1

WO2021088241A1 - Dustproof and anti-air-blowing micro-electro-mechanical microphone chip

Info

Publication number: WO2021088241A1
Application number: PCT/CN2019/130229
Authority: WO
Inventors: 周宗燐; 邱冠勋; 卫勇
Original assignee: 歌尔微电子有限公司
Priority date: 2019-11-04
Filing date: 2019-12-31
Publication date: 2021-05-14
Also published as: CN211209929U

Abstract

Disclosed is a dustproof and anti-air-blowing micro-electro-mechanical microphone chip, comprising a substrate, and a diaphragm and a back plate sequentially arranged on the upper side of the substrate. Air release valves are arranged on the diaphragm; air release holes are provided at the positions of the back plate corresponding to the air release valves on the diaphragm; and a shielding assembly for preventing the air release valves from completely extending is arranged on the sides of the air release holes away from the diaphragm. According to the present invention, by means of arranging the shielding assembly to prevent the air release valves from completely extending, when the air release valves are impacted by an airflow, the air release valves are opened, but due to the arrangement of the shielding assembly, the air release valves cannot completely extend, and fine dust is blocked outside the back plate due to the combined action of the air release valves and the shielding assembly, thereby effectively preventing the fine dust from entering the inside of a microphone. The present invention is simple and small in structure, and has a good dustproof capability, while also ensuring the anti-air-blowing capability.

Description

A dust-proof and air-blowing micro-electromechanical microphone chip

Technical field

The invention relates to the technical field of microphones, in particular to a dust-proof and air-blowing microelectromechanical microphone chip.

Background technique

Many MEMS microphones have a vent valve structure design on the diaphragm, and a hole is opened at the corresponding position of the back plate, so that the vent valve can be opened completely without obstruction when subjected to blowing pressure, creating a vent path while lowering the diaphragm. Understand the pressure. But when the opening of the vent valve is larger than the dust particles in the air, the dust particles will easily enter the inside of the microphone, and there will be a certain chance of dust on the microphone, or even fall between the diaphragm and the back plate, affecting the product Performance and reliability.

Therefore, it is necessary to propose an improvement to overcome the shortcomings of the prior art.

Summary of the invention

The purpose of the present invention is to solve the problems in the prior art and provide a dust-proof and anti-blowing microelectromechanical microphone chip that takes into account air leakage and prevents dust particles from entering the inside of the microphone.

The technical scheme of the present invention is:

A dust-proof and anti-blowing micro-electromechanical microphone chip, comprising a substrate, a diaphragm and a back plate arranged on the upper side of the substrate in turn, a bleed valve is arranged on the diaphragm, and a bleed valve on the back plate and the diaphragm The corresponding position is provided with a vent hole, and the side of the vent hole away from the diaphragm is provided with a shielding component that prevents the vent valve from being fully extended.

As a preferred technical solution, the shielding assembly includes a top shielding baffle for preventing the top of the bleed valve from being fully extended.

As a preferred technical solution, a gap is provided between the top shielding plate and the back electrode plate, and at least one side edge of the top shielding plate is connected to the back electrode plate through an extension plate.

As a preferred technical solution, one end of the top shielding plate along the opening direction of the bleed valve and away from the end of the bleed valve is connected to the back plate through an extension plate.

As a preferred technical solution, one end of the top shielding plate along the opening direction of the bleed valve and close to the end of the bleed valve is connected to the back plate through an extension plate.

As a preferred technical solution, both ends of the top shielding plate along the opening direction of the bleed valve are connected to the back plate through an extension plate.

As a preferred technical solution, both ends of the top shielding plate perpendicular to the opening direction of the bleed valve are connected to the back electrode plate through extension plates.

As a preferred technical solution, the shielding assembly includes a middle shielding plate for preventing the middle of the bleed valve from being fully extended, and the middle shielding plate is flatly attached to the back plate.

As a preferred technical solution, the end of the middle shielding plate facing away from the end of the bleed valve is connected to the back electrode plate, and there is a gap between the other end of the middle shielding plate and the back electrode plate.

As a preferred technical solution, the middle shielding plate is connected to the back electrode plate at two ends perpendicular to the opening direction of the bleed valve, and there is a gap between the two sides of the middle shielding plate and the back electrode plate.

The present invention also provides an electronic device, comprising the dust-proof and air-blowing microelectromechanical microphone chip described in the above claims. Beneficial effects: The present invention provides a shielding component that prevents the vent valve from fully extending. When the vent valve is impacted by the airflow, the vent valve opens. However, due to the setting of the shielding component, the vent valve cannot be fully extended, and fine dust is blocked by the vent valve The joint action of the components is blocked on the outside of the back plate, effectively preventing dust from entering the inside of the microphone. The structure of the invention is simple and compact, and has good dust-proof ability while ensuring the anti-blowing ability.

Description of the drawings

Figure 1 is a schematic diagram of the structure of the relief valve;

Figure 2 is a schematic cross-sectional view of the first embodiment;

Figure 3 is a schematic top view of the first embodiment;

4 is a schematic cross-sectional view of the second embodiment;

Figure 5 is a schematic top view of the second embodiment;

Figure 6 is a schematic cross-sectional view of the third embodiment;

Figure 7 is a schematic top view of the third embodiment;

Figure 8 is a schematic cross-sectional view of the fourth embodiment;

Figure 9 is a schematic top view of the fourth embodiment;

Figure 10 is a schematic cross-sectional view of the fifth embodiment;

Figure 11 is a schematic top view of the fifth embodiment;

Figure 12 is a schematic cross-sectional view of the sixth embodiment;

Figure 13 is a schematic top view of the sixth embodiment;

Among them: 1. Back plate, 2. Diaphragm, 3. Drain valve, 4. Dust, 5. Airflow, 6, Extension plate, 7. Top shielding baffle, 8. Middle shielding baffle, 1-1, Vent hole .

Detailed ways

In order to make the technical means, technical features, purpose and technical effects of the present invention easy to understand, the present invention will be further explained below in conjunction with specific drawings.

The microphone usually includes a substrate, a diaphragm 2 and a back plate 1. The diaphragm 2 and the back plate 1 are arranged on the upper side of the substrate in turn. In order to make the diaphragm 2 have good resistance to blow air impact, as shown in Figure 1. As shown, usually several sets of bleed valves 3 are arranged on the diaphragm 2. The structure of the bleed valve 3 is like a tongue structure, and in order to avoid affecting the opening of the bleed valve 3, the position of the bleed valve 3 on the back plate 1 will be provided with The vent hole 1-1, in order to prevent dust from entering the microphone when the vent valve 3 is opened by the impact of the air flow, this application provides the following types of vent holes 1-1 away from the side of the diaphragm 2 A shielding component that prevents the exhaust valve 3 from being fully extended is provided on it.

Example one

As shown in Figures 2 and 3, the shielding assembly of this embodiment includes a top shielding plate 7 used to prevent the top of the bleed valve 3 from being fully extended, and a top shielding plate 7 is provided between the top shielding plate 7 and the back plate 1 The height of the interval is lower than the maximum height when the bleed valve 3 is in the open state. The top cover 7 is connected to the back plate through an extension plate 6 along the opening direction of the bleed valve 3 and away from the end of the bleed valve 3 On 1, there is a certain interval between the other edges of the top shielding plate 7 and the edge of the vent hole 1-1, and the interval is used as the vent channel. The interval is compared with the height of the top shielding plate 7 and the height of the top shielding plate 7. The size is related, so the height of the top shielding plate 7 and the size of the top shielding plate 7 should be set to be smaller than the corresponding dust particle size of the dustproof level. When the bleed valve 3 is opened by the impact of the air flow 5, the end of the bleed valve 3 will be blocked and folded. The air flow 5 passes along the gap between the top baffle plate 7 and the bleed hole 1-1, and the fine dust is blocked on the back plate The outer side of 1, plays a role of dustproof and anti-blowing.

Example two

As shown in Figures 4 and 5, compared with the first embodiment, the main difference of the second embodiment is that the top cover 7 passes through the extension plate 6 along the opening direction of the bleed valve 3 and near the end of the bleed valve 3 Connected to the back plate 1, the structural principle of this embodiment is the same as the structural principle of the first embodiment, and the top shielding baffle 7 is arranged at the open end of the bleed valve 3, and the dustproof effect is better.

Example three

As shown in Figures 6 and 7, compared with the first embodiment, the main difference of the third embodiment is: the two ends of the top shielding plate 7 along the opening direction of the bleed valve are connected to the back plate through extension plates. In this embodiment, the above-mentioned setting method of the first embodiment and the setting method of the second embodiment are combined, and the air leakage channels are located on both sides of the top shielding baffle 7.

Example four

As shown in Figures 8 and 9, compared with the first embodiment, the main difference of the fourth embodiment is that the two ends of the top shielding plate 7 perpendicular to the opening direction of the bleed valve 3 are connected to the back by the extension plate 6. On the pole plate 1, compared with the third embodiment, it is equivalent to rotating the plane of the top shielding plate of the third embodiment by 90°. The air leakage channel of this embodiment is mainly the top shielding plate 7 close to the open end of the air venting valve 3.

Example five

As shown in Figures 10 and 11, compared with the first embodiment, the main difference of the fifth embodiment is that the shielding assembly includes a middle shielding baffle 8 for preventing the middle part of the bleed valve 3 from being fully extended. The shielding plate 8 is flatly attached to the back electrode plate 1. Flat attachment refers to the positional relationship between the middle shielding plate 8 and the back electrode plate 1, that is, the distance between the middle shielding plate 8 and the back electrode plate 1 is zero, so The end of the middle shielding plate 8 facing away from the end of the bleed valve 3 is connected to the back electrode plate 1, and there is a gap between the other side of the middle shielding plate 8 and the back electrode plate 1. Compared with the foregoing embodiment, there is no gap between the middle shielding plate 8 and the back plate 1. The middle shielding plate 8 is directly connected to the back plate 1. The height is low. After the middle part of the bleed valve 3 is shielded and folded, the end of the bleed valve 3 will extend into the interval between the middle shielding baffle 8 and the bleed hole 1-1, and the bleed valve 3 will occupy a certain space. Prevent dust from entering the inside of the microphone.

Example Six

As shown in Figures 12 and 13, compared with the fifth embodiment, the main difference of the sixth embodiment is that the middle shielding plate is connected to the back plate along the two ends perpendicular to the opening direction of the bleed valve, and the middle shielding There is a gap between the two sides of the plate and the back plate. As an evolution of the installation method of the middle shielding plate in the fifth embodiment, referring to the first to fourth embodiments, the middle shielding plate cannot be set on the open end of the suction valve because it is flat on the back plate, which will seriously affect the leakage Therefore, the setting is perpendicular to the opening direction of the bleed valve, which will not affect the bleed efficiency, but also has a good dust-proof effect.

Example Seven

This embodiment provides an electronic device, including the dust-proof and air-blowing-resistant microelectromechanical microphone chip described in the claims. The electronic device in this embodiment may be a mobile phone, a tablet computer, a portable notebook computer, and the like.

In summary, the above are only preferred embodiments of the present invention, and are not used to limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made in accordance with the content of the patent application scope of the present invention should belong to the technical scope of the present invention.

Claims

A dust-proof and anti-blowing microelectromechanical microphone chip includes a substrate, a diaphragm and a back plate fixedly arranged on the substrate, a vent valve is arranged on the diaphragm, and the back plate is opposite to the vent valve on the diaphragm. The corresponding position is provided with a vent hole, which is characterized in that: the side of the vent hole away from the diaphragm is provided with a shielding component that prevents the vent valve from being fully extended.
The dust-proof and air-blowing microelectromechanical microphone chip according to claim 1, wherein the shielding component includes a top shielding baffle for preventing the free end of the bleed valve from being fully extended.
The dust-proof and anti-blowing microelectromechanical microphone chip according to claim 2, wherein a gap is provided between the top shielding plate and the back plate, and at least one side edge of the top shielding plate is connected to the back through an extension plate. On the pole.
The dust-proof and air-blowing MEMS microphone chip according to claim 3, wherein the end of the top shielding plate along the opening direction of the bleed valve and away from the end of the bleed valve is connected to the back plate through an extension plate.
The dust-proof and anti-blowing MEMS microphone chip according to claim 3, wherein the end of the top shielding plate along the opening direction of the bleed valve and close to the end of the bleed valve is connected to the back plate through an extension plate.
The dust-proof and air-blowing microelectromechanical microphone chip according to claim 3, wherein both ends of the top shielding plate along the opening direction of the bleed valve are connected to the back plate through extension plates.
The dust-proof and air-blown microelectromechanical microphone chip according to claim 3, wherein the two ends of the top shielding plate perpendicular to the opening direction of the bleed valve are connected to the back plate through extension plates.
The dust-proof and anti-blowing microelectromechanical microphone chip according to claim 1, wherein the shielding component includes a middle shielding baffle for preventing the middle of the bleed valve from being fully extended, and the middle shielding baffle is flat on the back On the pole.
The dust-proof and anti-blowing MEMS microphone chip according to claim 8, wherein the end of the middle shielding plate facing away from the end of the bleed valve is connected to the back electrode plate, and the other end of the middle shielding plate is connected to the back electrode. There are gaps between the plates.
The dust-proof and anti-blowing microelectromechanical microphone chip according to claim 8, wherein the middle shielding plate is connected to the back plate along two ends perpendicular to the opening direction of the bleed valve, and both sides of the middle shielding plate There is a gap between the back plate and the back plate.