WO2021134665A1

WO2021134665A1 - Mems speaker and manufacturing method therefor

Info

Publication number: WO2021134665A1
Application number: PCT/CN2019/130899
Authority: WO
Inventors: 程诗阳; 李杨; 但强; 朱国
Original assignee: 瑞声声学科技(深圳)有限公司; 瑞声科技（南京）有限公司
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2021-07-08

Abstract

Disclosed are a MEMS speaker and a manufacturing method therefor. The MEMS speaker comprises a substrate, a vibrating component, a diaphragm, and a connecting rod. The substrate comprises a base and a support base that extends from a side of the base, a first cavity is penetratingly provided in the direction of the thickness of the base, the support base is annular and encloses to form a second cavity that communicates with the first cavity, and the inner diameter of the first cavity in the direction perpendicular to the thickness is less than that of the second cavity. The vibrating component is fixed to the substrate and at least covers a part of the first cavity, one end of the connecting rod is connected to the vibrating component, the other end thereof extends to the second cavity by means of the first cavity and is connected to the diaphragm, and the diaphragm is suspended in the second cavity and is spaced apart from an inner wall of the support base. According to the MEMS speaker of the present invention, a vibrating member drives the diaphragm to perform piston movement to thus generate sound so that a larger volume of air can be discharged per unit time, thereby improving the sound output of the MEMS speaker.

Description

MEMS speaker and manufacturing method thereof

Technical field

The present invention relates to the technical field of acoustic-electric conversion, in particular to a MEMS speaker and a manufacturing method of the MEMS speaker.

Background technique

A speaker is a transducer device that converts electrical signals into sound signals. It is widely used in various audio and mobile terminal equipment. The performance of the speaker will directly affect the sound quality of the audio or mobile terminal equipment.

In the prior art, the diaphragm in a speaker usually produces sound through the vibration of the diaphragm. However, since the edge of the diaphragm usually needs to be fixed to other components, the center part of the diaphragm has a large vibration amplitude, while the peripheral part has a large vibration amplitude. Is small, resulting in lower sound output from the speaker.

Summary of the invention

technical problem

Therefore, it is necessary to provide an improved speaker to solve the above-mentioned problems.

The solution to the problem

Technical solutions

One of the objectives of the present invention is to provide a MEMS speaker, which has the advantage of high sound output.

One of the objectives of the present invention is achieved by adopting the following technical solutions:

A MEMS speaker includes a base, a vibrating component, a diaphragm, and a connecting rod. The base includes a base and a support base extending from one side of the base. The base is provided with a first cavity along its thickness direction. The supporting seat is annular and encloses to form a second cavity communicating with the first cavity, and the inner diameter of the first cavity along the thickness direction perpendicular to the thickness direction is smaller than that of the second cavity; The vibration component is fixed to the base and covers at least part of the first cavity. One end of the connecting rod is connected to the vibration component, and the other end extends to the second cavity through the first cavity and is connected to the The diaphragm is connected, and the diaphragm is suspended in the second cavity and is spaced apart from the inner wall of the support seat.

As an improvement, the base is provided with at least two first cavities spaced apart, each of the first cavities communicates with the second cavity, and the first cavity and the vibration assembly There is a one-to-one correspondence with the connecting rods, and the vibration components are all connected to the same diaphragm through the corresponding connecting rods.

As an improvement, the vibrating assembly includes a vibrating member arranged on a side of the base away from the supporting seat and a driver arranged on the vibrating member, and the vibrating member covers at least a part of the first cavity.

As an improvement, each of the vibrating components includes two drivers, and the two drivers are fixed on the side of the vibrating member away from the support base and symmetrically arranged on opposite sides of the connecting rod .

As an improvement, the driver includes a first electrode layer connected to the vibrating member, a piezoelectric layer disposed on a side of the first electrode layer away from the vibrating member, and a piezoelectric layer disposed far away from the piezoelectric layer. The second electrode layer on one side of the first electrode layer.

As an improvement, the vibrating member includes a diaphragm and a connecting beam, one side of the diaphragm is connected to the base, and the other side extends toward the connecting rod and is spaced apart from the connecting rod. The connecting beam is connected between the diaphragm and the connecting rod.

As an improvement, the diaphragm is provided with at least two and symmetrically arranged on the outer circumference of the connecting rod, and each side of the diaphragm away from the base is provided with a driver.

As an improvement, the connecting beam is L-shaped or serpentine-shaped.

As an improvement, the diaphragm is suspended in the first cavity and is fixed with the base only on the side far away from the connecting rod.

As an improvement, the MEMS speaker is square or circular, and the connecting rods are distributed at equal intervals.

The second objective of the present invention also provides a method for manufacturing a MEMS speaker, including:

A first silicon wafer having a first surface and a second surface is provided, a number of first cavities extending from the first surface to the second surface are etched on the first silicon wafer, and the etched The first silicon wafer includes a first wafer body provided with the first cavity and a first protrusion provided in the first cavity;

Cover a buffer layer on the side of the etched first silicon wafer away from the second surface;

An SOI wafer is provided. The SOI wafer includes a first silicon layer, a second silicon layer, and a silicon oxide layer sandwiched between the first silicon layer and the second silicon layer to fix the first silicon layer On the side of the buffer layer away from the first silicon wafer, removing the second silicon layer and the silicon oxide layer, and thinning the first silicon layer to a certain thickness;

Processing the thinned first silicon layer to form a vibrating member, and disposing a driver on the vibrating member to form a vibrating component;

Etching the second surface corresponding to the position of the first cavity, so that the first cavity penetrates the first wafer main body, and a susceptor with a first cavity is manufactured;

A second silicon wafer is provided, and a second cavity is etched on the second silicon wafer. The second silicon wafer after etching includes a second wafer body provided with the second cavity and a The second convex post in the two concave cavities;

The etched second silicon wafer is fixed on the side of the first silicon wafer away from the buffer layer, and the second wafer body is connected to the first wafer body so that the first cavity and The second cavity is in communication, and the second convex column is connected with the first convex column to form a connecting rod;

The side of the second wafer body away from the first wafer body is etched corresponding to the position of the second cavity to form a third cavity, and the third cavity and the second cavity pass through and The partitions connected by the connecting rods are separated;

The edge of the partition is etched away to form a gap connecting the second cavity and the third cavity to form a support seat and a diaphragm, and the support seat encloses a second for accommodating the diaphragm. Cavity.

The beneficial effects of the invention

Beneficial effect

Compared with the prior art, the embodiment of the present invention is provided with a first cavity on the base, the supporting seat encloses the second cavity, the vibration component is arranged in the first cavity, and the diaphragm is arranged in the second cavity, And the two are connected by a connecting rod. When vibrating, the vibrating component will drive the diaphragm to move the piston through the connecting rod. When the diaphragm moves the piston, it will push the air to produce sound. The vibration component needs to be fixed to the base, so it will Obstructed by the base, the overall amplitude of the vibrating component is small. Since the diaphragm is suspended in the second cavity through the connecting rod and is spaced from the inner wall of the support base, it will not be supported during the movement. The obstruction of the seat, the diaphragm can produce a greater amplitude of movement, that is, the diaphragm has a greater amplitude, so that it can expel more volume of air per unit time. Therefore, the movement of the diaphragm piston produces sound. Compared with direct vibration through the vibrating component, the sound output of the MEMS speaker can be improved; and because the diaphragm and the vibrating component are not installed in the same cavity, the size of the diaphragm will not be affected by the size of the first cavity, and the second cavity The inner diameter of the body is larger than the inner diameter of the first cavity, so a diaphragm with a size larger than the size of the first cavity can be provided, so that the diaphragm can discharge more volume of air per unit time, thereby further improving the sound output of the MEMS speaker.

Brief description of the drawings

Description of the drawings

FIG. 1 is a schematic structural diagram of a MEMS speaker provided by Embodiment 1 of the present invention;

Fig. 2 is a schematic cross-sectional view taken along line A to A of Fig. 1;

FIG. 3 is a schematic diagram of the structure of the MEMS speaker shown in FIG. 1 from another angle;

Fig. 4 is a partial enlarged schematic diagram of B in Fig. 3;

5 is a schematic diagram of structural changes during the manufacturing process of the MEMS speaker provided by the first embodiment of the present invention;

6 is a schematic diagram of the structure of a MEMS speaker provided by the second embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a MEMS speaker provided by Embodiment 3 of the present invention.

Reference signs: 100, MEMS speaker; 10, base; 20, vibrating component; 30, diaphragm; 40, connecting rod; 11, base; 12, support seat; 111, first cavity; 121, second cavity 122. Inner wall; 21. Vibration member; 22. Driver; 221. First electrode layer; 222. Piezoelectric layer; 223. Second electrode layer; 211. Diaphragm; 212. Connecting beam; 213. Hollowed area; 50 51, the first surface; 52, the second surface; 53, the first cavity; 54, the first wafer body; 55, the first convex pillar; 60, buffer layer; 70, SOI wafer; 71 72, the second silicon layer; 73, the silicon oxide layer; 80, the second silicon wafer; 81, the second cavity; 82, the second wafer body; 83, the second convex pillar; 84, the first Three-cavity; 85, partition; 86, gap; 200, MEMS speaker; 11′, base; 111′, first cavity; 300, MEMS speaker; 21″, vibrating member; 11″, base; 111 ", the first cavity.

Invention embodiment

Detailed ways

The present invention will be further described below in conjunction with the drawings and embodiments.

It should be noted that all directional indicators (such as up, down, left, right, front, back, inside, outside, top, bottom...) in the embodiments of the present invention are only used to explain that they are in a specific posture (as attached As shown in the figure below), the relative positional relationship between the components, etc., if the specific posture changes, the directional indication will also change accordingly.

It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, the element may be directly on the other element or there may be a centering element at the same time. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or an intermediate element may be present at the same time.

Example one:

1 to 4, a MEMS speaker 100 provided in accordance with an embodiment of the present invention includes a base 10, a vibration component 20, a diaphragm 30, and a connecting rod 40. The base 10 includes a base 11 and a support base 12, and the support base 12 Extending from one side of the base 11 in a direction away from the base 11, the base 11 is provided with a first cavity 111 along its thickness direction, which is also the direction in which the support base 12 extends, and the support base 12 has a circular shape. The second cavity 121 connected with the first cavity 111 is enclosed and formed. The inner diameter of the first cavity 111 in the direction perpendicular to the thickness of the base 11 is smaller than that of the second cavity 121, that is, the contour of the first cavity 111 is smaller than The second cavity 121, the vibration component is fixed to the base 11 and covers at least part of the first cavity 111, one end of the connecting rod 40 is connected to the vibration component 20, and the other end extends into the second cavity 121 through the first cavity 111 The diaphragm 30 is fixedly connected to the diaphragm 30. The diaphragm 30 is suspended in the second cavity 121 and is spaced apart from the inner wall 122 of the support base 12 (that is, the cavity wall of the second cavity 121).

By providing a first cavity 111 on the base 11 and a second cavity 121 on the support base 12, the diaphragm 30 is connected to the vibrating assembly 20 through the connecting rod 40, so that the diaphragm 30 is suspended in the second cavity 121, Since the vibration assembly 20 needs to be fixed to the base 11, the vibration assembly 20 will be hindered by the base 11 when vibrating. Only the part covering the first cavity 111 can vibrate, and the vibration amplitude is from the center of the first cavity 111 to The edge is gradually reduced, resulting in a smaller overall amplitude of the vibrating assembly 20, but when the vibrating assembly 20 vibrates, the diaphragm 30 is driven to move together through the connecting rod 40, and the air is pushed by the diaphragm 30 to generate sound. Because the diaphragm 30 is suspended on In the second cavity 121, there is a gap between its edge and the inner wall 122 of the support base 12, so the diaphragm 30 will move in the thickness direction of the base 11, and its movement will not be affected by the support base 12, so it supports The overall amplitude of the base 12 is relatively large, and the displacement of each part is the same, and more volume of air can be discharged per unit time, thereby improving the sound output of the MEMS speaker 100.

In this embodiment, the contour of the first cavity 111 is smaller than the contour of the second cavity 121, and the vibration assembly 20 and the diaphragm 30 are installed in the first cavity 111 and the second cavity 121 respectively. Therefore, the size of the diaphragm 30 is different. It is restricted by the first cavity 111 and only restricted by the second cavity 121, so that the size of the diaphragm 30 can be set larger than that of the first cavity 111, compared to installing the vibrating assembly 20 and the diaphragm 30 on the same In the solution in the cavity, when the size of the vibrating component 20 is the same, the MEMS speaker 100 of this embodiment can be provided with a larger-sized diaphragm 30, thereby improving the sound output of the MEMS speaker 100.

Preferably, the support base 12 and the base 11 are fixed together by bonding, and the base 11, the support base 12, the diaphragm 30 and the connecting rod 40 are all made of silicon wafers.

As an improvement of this embodiment, the base 11 is provided with at least two first cavities 111 spaced apart, each of the first cavities 111 communicates with the second cavity 121, the first cavity 111, the vibration component 20, and The number of connecting rods 40 is the same and corresponds to each other, and each vibrating component 20 is connected to the same diaphragm 30 through a corresponding connecting rod 40.

By providing at least two vibration components 20, each vibration component 20 is connected to the diaphragm 30 through a corresponding connecting rod 40, and all the vibration components 20 jointly drive the diaphragm 30 to make a piston movement, which enhances the stability of the movement of the diaphragm 30, and when When the connecting rod 40 is broken or other accidents, as long as the MEMS speaker 100 has a connecting rod 40 connecting the diaphragm 30 and the vibration component 20, the MEMS speaker 100 can drive the diaphragm 30 to move through the vibration component 20 to produce sound, which improves the performance of the MEMS speaker 100. reliability.

Preferably, the size of the two ends of the connecting rod 40 connected to the vibration assembly 20 and the diaphragm 30 are the same. It is understandable that the size of the two ends of the connecting rod 40 may also be different. For example, the size of the end (that is, the top) of the connecting rod 40 connected to the vibration assembly 20 may be smaller than that of the connecting rod 40 connected to the diaphragm 30. The size of the end (that is, the bottom end), the connecting rod 40 is set in a special shape with a small top end and a large bottom end, which can not only ensure the connection strength of the connecting rod 40 and the diaphragm 30, but also avoid the influence of the connecting rod 40 being too large. The problem of vibration of the vibration assembly 20.

As an improvement of this embodiment, the vibration assembly 20 includes a vibration member 21 connected to the side of the base 11 away from the support base 12 and a driver 22 provided on the vibration member 21. The vibration member 21 covers at least part of the first cavity 111 .

Preferably, each vibrating assembly 20 includes two drivers 22, and the two drivers 22 are fixed to the side of the vibrating member 21 away from the support base 12 and are symmetrically arranged on opposite sides of the connecting rod 40.

By providing two drivers 22 on one vibrating member 21, the amplitude of the vibrating member 21 can be increased, that is, the amplitude of the diaphragm 30 can be enhanced, thereby improving the sound output of the MEMS speaker 100.

It can be understood that the number of drivers 22 on one vibrating member 21 is not limited to the above two, for example, one or more drivers are also possible.

As an improvement of this embodiment, the driver 22 includes a first electrode layer 221 connected to the vibrating member 21, a piezoelectric layer 222 disposed on the side of the first electrode layer 221 away from the vibrating member 21, and a piezoelectric layer 222 disposed on the piezoelectric layer. 222 is away from the second electrode layer 223 on the side of the first electrode layer 221.

Preferably, the first electrode layer 221 and the second electrode layer 223 are made of conductive metal, and the piezoelectric layer 222 is made of piezoelectric material. The piezoelectric material may be aluminum nitride, or zinc oxide, or lead zirconate titanate.

As an improvement of this embodiment, the vibrating member 21 includes a diaphragm 211 and a connecting beam 212. One side of the diaphragm 211 is connected to the base 11, and the other side extends toward the connecting rod 40 and is spaced apart from the connecting rod 40. The connecting beam 212 is connected between the diaphragm 211 and the connecting rod 40.

After the diaphragm 211 vibrates, the vibration is first transmitted to the connecting beam 212, causing the connecting rod 40 to move, thereby driving the diaphragm 30 to make a piston movement. Because there is a distance between the diaphragm 211 and the connecting rod 40 and is connected by the connecting beam 212, The rigidity of the connecting part of the vibrating member 21 and the connecting rod 40 is reduced, and the vibrating member 21 is convenient to vibrate.

Preferably, in order to further reduce the rigidity of the connection part between the vibrating member 21 and the connecting rod 40, the connecting beam 212 is made of a flexible film material.

It can be understood that the vibrating member 21 is not limited to the form of the diaphragm 211 plus the connecting beam 212, for example, the form of a cantilever beam is also possible.

As an improvement of this embodiment, at least two diaphragms 211 are provided, and the diaphragms 211 are symmetrically arranged on the outer circumference of the connecting rod 40, and each diaphragm 211 is provided with a driver on the side away from the base 11 twenty two.

Preferably, in this embodiment, each vibrating member 21 includes two diaphragms 211 and four connecting beams 212. The two diaphragms 211 are symmetrically arranged on both sides of the connecting rod 40, thereby enhancing the stability of the movement of the diaphragm 30. Two connecting beams 212 are connected between each diaphragm 211 and the connecting rod 40. The connecting beam 212 is L-shaped, and both ends of the connecting beam 212 are connected to the diaphragm 211 and the connecting rod 40, respectively. The diaphragm 211 The two connecting beams 212 connected to the diaphragm 211 and the connecting rod 40 are enclosed to form a hollow area 213, which further reduces the rigidity of the connecting part of the vibrating member 21 and the connecting rod 40.

It can be understood that the shape of the connecting beam 212 is not limited to the above-mentioned L shape, for example, a serpentine shape is possible.

As an improvement of this embodiment, the diaphragm 211 is suspended in the first cavity 111 and is fixed to the base 11 only on the side far away from the connecting rod 40.

In this embodiment, the diaphragm 211 has a square shape, and its opposite sides are respectively connected to the base 11 and the connecting beam 212, and the opposite sides are spaced apart from the cavity wall of the first cavity 111, thereby facilitating the diaphragm 211 Vibration.

Preferably, the MEMS speaker 100 is square, and there are four first cavities 111, and the four first cavities 111 are arranged in two rows and two columns, that is, the four first cavities 111 are arranged symmetrically in pairs. Each first cavity 111 is provided with a vibration assembly 20 connected to the diaphragm 30 through a connecting rod 40, which ensures the stability of the movement of the diaphragm 30.

Referring to FIG. 5, an embodiment of the present invention also provides a manufacturing method S100 of a MEMS speaker 100, including:

In step S10, a first silicon wafer 50 having a first surface 51 and a second surface 52 is provided, a number of first cavities 53 extending from the first surface 51 to the second surface 52 are etched on the first silicon wafer 50, and the etching The subsequent first silicon wafer 50 includes a first wafer main body 54 provided with a first cavity 53 and a first protrusion 55 provided in the first cavity 53;

Step S20, covering a buffer layer 60 on the side of the etched first silicon wafer 50 away from the second surface 52, and the buffer layer 60 is made of silicon oxide;

In step S30, an SOI wafer 70 is provided. The SOI wafer 70 includes a first silicon layer 71, a second silicon layer 72, and a silicon oxide layer 73 sandwiched between the first silicon layer 71 and the second silicon layer 72. The layer 71 is fixed on the side of the buffer layer 60 away from the first silicon wafer 50 by bonding, the first silicon layer 71 and the silicon oxide layer 73 are removed, and the first silicon layer 71 is thinned to a certain thickness;

Step S40, processing the thinned first silicon layer 71 to form the vibrating member 21, and setting the driver 22 on the vibrating member 21 to form the vibrating component 20;

Step S50, etching the second surface 52 corresponding to the position of the first cavity 53 so that the first cavity 53 penetrates through the first wafer main body 54 to form the base 11 with the first cavity 111;

In step S60, a second silicon wafer 80 is provided, and a second cavity 81 is etched on the second silicon wafer 80. The etched second wafer includes a second wafer body 82 provided with a second cavity 81 and a second wafer body 82 provided with a second cavity 81. The second convex post 83 in the cavity 81;

In step S70, the etched second silicon wafer 80 is fixed to the side of the first silicon wafer 50 away from the buffer layer 60 by bonding, and the second wafer body 82 is connected to the first wafer body 54 to make the first cavity 111 Communicate with the second cavity 81, and the second convex column 83 is connected with the first convex column 55 to form a connecting rod 40;

Step S80, the side of the second wafer body 82 away from the first wafer body 54 is etched corresponding to the position of the second cavity 81 to form a third cavity 84, and the third cavity 84 and the second cavity 81 are connected by and The partition 85 connected by the rod 40 is separated;

In step S90, the edge of the partition 85 is etched to form a gap 86 connecting the second cavity 81 and the third cavity 84, so that the support base 12 and the diaphragm 30 are formed. The support base 12 is enclosed to form a first portion for accommodating the diaphragm 30. Two cavities 121.

In this embodiment, the first silicon wafer 50 and the second silicon wafer 80 are both square, and the number of the first cavities 53 is four, and the four first cavities 53 are symmetrically distributed in pairs, and the second cavities The number of 81 is one, and the size of the second cavity 81 is larger than the size of the first cavity 53, the base 11, the first protrusion 55, the vibrating member 21, the support base 12, the second protrusion 83 and the diaphragm 30 Both are formed by etching, the base 11 and the support base 12 are fixed together by bonding to form the base 10, the first protrusion 55 and the second protrusion 83 are fixed together by bonding to form the connecting rod 40, and the vibrating member 21 is also fixed to the buffer layer 60 by bonding, that is, the base 11, the support base 12, the vibrating member 21, the first protrusion 55, and the second protrusion 83 are integrally formed to ensure that the manufacturing The overall strength of the MEMS speaker 100 obtained by the method.

Embodiment two:

Referring to FIG. 6, the MEMS speaker 200 provided in this embodiment is compared with the MEMS speaker 100 provided in the first embodiment: the base 11' of this embodiment is provided with three first cavities 111' at intervals, and three first cavities The bodies 111 ′ are distributed at equal intervals along the length direction of the MEMS speaker 200. It can be understood that the number of the first cavities 111 ′ is not limited to three, for example, one, two, or multiple other numbers are also possible.

Embodiment three:

Referring to FIG. 7, the MEMS speaker 300 provided in this embodiment is compared with the MEMS speaker 100 provided in the first embodiment: the MEMS speaker 300 in this embodiment is cylindrical, and the vibrating member 21" is in the form of a cantilever beam, and the base 11" Three first cavities 111" are opened on the top, and the three first cavities 111" are equally spaced along the circumference of the base 11", and the included angle between any two adjacent cantilever beams is 120°. It is understandable. However, the number of the first cavities 111" is not limited to three, for example, one, two, or other numbers are also possible.

The above are only the embodiments of the present invention. It should be pointed out here that for those of ordinary skill in the art, improvements can be made without departing from the inventive concept of the present invention, but these all belong to the present invention. The scope of protection.

Claims

A MEMS speaker, characterized in that it comprises a base, a vibrating component, a diaphragm, and a connecting rod. The base includes a base and a support base extending from one side of the base. The first cavity, the support seat is annular and encloses to form a second cavity communicating with the first cavity, and the inner diameter of the first cavity along the thickness direction perpendicular to the thickness direction is smaller than that of the second cavity The vibrating component is fixed to the base and covers at least part of the first cavity, one end of the connecting rod is connected to the vibrating component, and the other end extends through the first cavity to the second The cavity is connected with the diaphragm, and the diaphragm is suspended in the second cavity and is spaced apart from the inner wall of the support seat.
The MEMS speaker according to claim 1, wherein the base is provided with at least two first cavities spaced apart, and each of the first cavities is in communication with the second cavity, and the The first cavity has a one-to-one correspondence with the vibration component and the connecting rod, and the vibration components are all connected to the same diaphragm through the corresponding connecting rod.
The MEMS speaker according to claim 1, wherein the vibrating assembly comprises a vibrating member provided on the side of the base away from the support base and a driver provided on the vibrating member, and the vibrating member is at least Covering part of the first cavity.
The MEMS speaker according to claim 3, wherein each of the vibrating components includes two drivers, and the two drivers are fixed on a side of the vibrating member away from the support base and arranged symmetrically On opposite sides of the connecting rod.
The MEMS speaker according to claim 3, wherein the driver comprises a first electrode layer connected to the vibrating member, a piezoelectric layer provided on a side of the first electrode layer away from the vibrating member, And a second electrode layer disposed on the side of the piezoelectric layer away from the first electrode layer.
The MEMS speaker according to claim 3, wherein the vibrating member comprises a diaphragm and a connecting beam, one side of the diaphragm is connected to the base, and the other side extends toward the connecting rod and connects with The connecting rods are arranged at intervals, and the connecting beams are connected between the diaphragm and the connecting rods.
The MEMS speaker according to claim 6, wherein the diaphragm is provided with at least two and is symmetrically arranged on the outer circumference of the connecting rod, and each of the diaphragms has a side away from the base. There is one said driver.
The MEMS speaker according to claim 6, wherein the connecting beam is L-shaped or serpentine-shaped.
7. The MEMS speaker according to claim 6, wherein the diaphragm is suspended in the first cavity and is fixed with the base only on a side away from the connecting rod.
The MEMS speaker according to claim 2, wherein the MEMS speaker is square or circular, and the connecting rods are distributed at equal intervals.
A method for manufacturing a MEMS speaker, which is characterized in that it comprises:

A first silicon wafer having a first surface and a second surface is provided, a number of first cavities extending from the first surface to the second surface are etched on the first silicon wafer, and the etched The first silicon wafer includes a first wafer body provided with the first cavity and a first protrusion provided in the first cavity;

Cover a buffer layer on the side of the etched first silicon wafer away from the second surface;

An SOI wafer is provided. The SOI wafer includes a first silicon layer, a second silicon layer, and a silicon oxide layer sandwiched between the first silicon layer and the second silicon layer to fix the first silicon layer On the side of the buffer layer away from the first silicon wafer, removing the second silicon layer and the silicon oxide layer, and thinning the first silicon layer to a certain thickness;

Processing the thinned first silicon layer to form a vibrating member, and disposing a driver on the vibrating member to form a vibrating component;

Etching the second surface corresponding to the position of the first cavity, so that the first cavity penetrates the first wafer main body, and a susceptor with a first cavity is manufactured;

A second silicon wafer is provided, and a second cavity is etched on the second silicon wafer. The second silicon wafer after etching includes a second wafer body provided with the second cavity and a The second convex post in the two concave cavities;

The etched second silicon wafer is fixed on the side of the first silicon wafer away from the buffer layer, and the second wafer body is connected to the first wafer body so that the first cavity and The second cavity is in communication, and the second convex column is connected with the first convex column to form a connecting rod;

The side of the second wafer body away from the first wafer body is etched corresponding to the position of the second cavity to form a third cavity, and the third cavity and the second cavity pass through and The partitions connected by the connecting rods are separated;

The edge of the partition is etched away to form a gap connecting the second cavity and the third cavity to form a support seat and a diaphragm, and the support seat encloses a second for accommodating the diaphragm. Cavity.