CN111182428A

CN111182428A - MEMS speaker and manufacturing method thereof

Info

Publication number: CN111182428A
Application number: CN201911423328.3A
Authority: CN
Inventors: 程诗阳; 李杨; 但强; 朱国
Original assignee: Ruisheng Technology Nanjing Co Ltd
Current assignee: AAC Technologies Holdings Nanjing Co Ltd; Ruisheng Technology Nanjing Co Ltd
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2020-05-19
Anticipated expiration: 2039-12-31
Also published as: CN111182428B

Abstract

The invention discloses an MEMS loudspeaker and a manufacturing method thereof, wherein the MEMS loudspeaker comprises a substrate, a vibration component, a diaphragm and a connecting rod, the substrate comprises a base and a supporting seat extending from one side of the base, the base is provided with a first cavity body in a penetrating manner along the thickness direction of the base, the supporting seat is annular and encloses to form a second cavity body communicated with the first cavity body, and the inner diameter of the first cavity body along the direction vertical to the thickness direction is smaller than that of the second cavity body; the vibration component is fixed on the substrate and at least covers part of the first cavity, one end of the connecting rod is connected with the vibration component, the other end of the connecting rod extends to the second cavity through the first cavity and is connected with the diaphragm, and the diaphragm is suspended in the second cavity and is arranged at intervals with the inner wall of the supporting seat. The MEMS loudspeaker of the invention generates sound by driving the diaphragm to do piston motion through the vibration component, so that more air can be discharged in unit time, thereby improving the sound output of the MEMS loudspeaker.

Description

MEMS speaker and manufacturing method thereof

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of sound-electricity conversion, in particular to an MEMS (micro-electromechanical system) loudspeaker and a manufacturing method of the MEMS loudspeaker.

[ background of the invention ]

The loudspeaker is a transducer for converting an electrical signal into a sound signal, and is widely applied to various sound equipment and mobile terminal equipment, and the quality of the performance of the loudspeaker directly influences the tone quality of the sound equipment or the mobile terminal equipment.

In the prior art, a diaphragm in a loudspeaker usually generates sound through vibration of the diaphragm, but because the edge of the diaphragm usually needs to be fixed to other parts, the central part of the diaphragm has large vibration amplitude, and the peripheral part has small vibration amplitude, so that the sound output of the loudspeaker is low.

Therefore, there is a need to provide an improved speaker to solve the above problems.

[ summary of the invention ]

It is an object of the present invention to provide a MEMS speaker having an advantage of high sound output.

One of the purposes of the invention is realized by adopting the following technical scheme:

an MEMS loudspeaker comprises a substrate, a vibration assembly, a diaphragm and a connecting rod, wherein the substrate comprises a base and a supporting seat extending from one side of the base, a first cavity penetrates through the base along the thickness direction of the base, the supporting seat is annular and encloses to form a second cavity communicated with the first cavity, and the inner diameter of the first cavity along the direction perpendicular to the thickness direction is smaller than that of the second cavity; the vibration component is fixed in the basement and at least cover part the first cavity, the one end of connecting rod with the vibration component is connected, the other end warp the first cavity extends to the second cavity and with the diaphragm is connected, the diaphragm hang locate in the second cavity and with the inner wall interval setting of supporting seat.

As an improvement, the base is provided with at least two first cavities at intervals, each first cavity is communicated with the second cavity, the first cavities correspond to the vibration assemblies and the connecting rods one to one, and the vibration assemblies are connected with the same diaphragm through the corresponding connecting rods.

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

As an improvement, each of the vibration assemblies includes two of the drivers, and the two drivers are fixed on one side of the vibration member away from the supporting seat and symmetrically arranged on two opposite sides of the connecting rod.

As an improvement, the driver includes a first electrode layer connected to the vibration member, a piezoelectric layer provided on a side of the first electrode layer away from the vibration member, and a second electrode layer provided on a side of the piezoelectric layer away from the first electrode layer.

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

As an improvement, the vibrating diaphragms are provided with at least two and symmetrically arranged on the peripheries of the connecting rods, and one side, away from the base, of each vibrating diaphragm is provided with one driver.

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

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

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

Another object of the present invention is to provide a method for manufacturing a MEMS speaker, comprising:

providing a first silicon wafer with a first surface and a second surface, etching a plurality of first cavities on the first silicon wafer, wherein the first cavities extend from the first surface to the second surface, and the etched first silicon wafer comprises a first wafer body provided with the first cavities and first convex columns arranged in the first cavities;

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

providing an SOI wafer, wherein the SOI wafer comprises a first silicon layer, a second silicon layer and a silicon oxide layer clamped between the first silicon layer and the second silicon layer, fixing the first silicon layer on one side of the buffer layer far 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 vibration component, and arranging a driver on the vibration component to form a vibration assembly;

etching the second surface corresponding to the position of the first cavity so that the first cavity penetrates through the first wafer body to obtain a base with a first cavity;

providing a second silicon wafer, etching a second concave cavity on the second silicon wafer, wherein the etched second silicon wafer comprises a second wafer main body provided with the second concave cavity and a second convex column arranged in the second concave cavity;

fixing the etched second silicon wafer on one side of the first silicon wafer, which is far away from the buffer layer, wherein the second wafer main body is connected with the first wafer main body so as to enable the first cavity to be communicated with the second cavity, and the second convex column is connected with the first convex column so as to form a connecting rod;

etching one side, away from the first wafer main body, of the second wafer main body corresponding to the position of the second cavity to form a third cavity, wherein the third cavity is separated from the second cavity through a partition plate connected with the connecting rod;

etching the edge of the partition plate to form a gap communicated with the second cavity and the third cavity, so as to obtain the supporting seat and the diaphragm, wherein the supporting seat is surrounded to form a second cavity for accommodating the diaphragm.

Compared with the prior art, the vibration component is arranged in the first cavity, the diaphragm is arranged in the second cavity and connected with the first cavity and the second cavity through the connecting rod, the diaphragm is driven to do piston motion through the connecting rod when vibrating, the diaphragm pushes air when doing piston motion to generate sound, the vibration component is fixed to the base and is blocked by the base when vibrating, so that the whole amplitude of the vibration component is smaller, the diaphragm is suspended in the second cavity through the connecting rod and is arranged at intervals with the inner wall of the supporting seat, so that the diaphragm cannot be blocked by the supporting seat when moving, can move to a larger extent, namely, the diaphragm has larger amplitude, so that the diaphragm can exhaust more air in unit time, therefore, the sound is generated through the movement of the diaphragm piston, and compared with the sound generated through the vibration of the vibration component directly, the sound output of the MEMS loudspeaker can be improved; and because diaphragm and vibration subassembly are not installed in same cavity, consequently the size of diaphragm can not receive the influence of first cavity size, and the internal diameter of second cavity is greater than the internal diameter of first cavity moreover, consequently can set up the diaphragm that the size is greater than first cavity size, makes the diaphragm can drive more voluminous air in unit interval to further promote MEMS speaker's sound output.

[ description of the drawings ]

Fig. 1 is a schematic structural diagram of a MEMS speaker according to an embodiment of the present invention;

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

FIG. 3 is a schematic view of the MEMS speaker of FIG. 1 at another angle;

FIG. 4 is an enlarged view of a portion of FIG. 3 at B;

fig. 5 is a schematic diagram illustrating a structural change in a manufacturing process of a MEMS speaker according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a MEMS speaker according to a second embodiment of the present invention;

fig. 7 is a schematic structural diagram of a MEMS speaker according to a third embodiment of the present invention.

Reference numerals: 100. a MEMS speaker; 10. a substrate; 20. a vibrating assembly; 30. a diaphragm; 40. a connecting rod; 11. a base; 12. a supporting seat; 111. a first cavity; 121. a second cavity; 122. an inner wall; 21. a vibration member; 22. a driver; 221. a first electrode layer; 222. a piezoelectric layer; 223. a second electrode layer; 211. vibrating diaphragm; 212. a connecting beam; 213. a hollow-out area; 50. a first silicon wafer; 51. a first surface; 52. a second surface; 53. a first cavity; 54. a first wafer body; 55. a first convex column; 60. a buffer layer; 70. an SO I wafer; 71. a first silicon layer; 72. a second silicon layer; 73. a silicon oxide layer; 80. a second silicon wafer; 81. a second cavity; 82. a second wafer body; 83. a second convex column; 84. a third cavity; 85. a partition plate; 86. a gap; 200. a MEMS speaker; 11', a base; 111', a first cavity; 300. a MEMS speaker; 21", a vibrating member; 11', a base; 111", first cavity.

[ detailed description ] embodiments

The invention is further described with reference to the following figures and embodiments.

It should be noted that all directional indicators (such as upper, lower, left, right, front, back, inner, outer, top, bottom … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components in a specific posture (as shown in the figure), and if the specific posture is changed, the directional indicator is changed accordingly.

It will also be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

The first embodiment is as follows:

referring to fig. 1 to 4, a MEMS speaker 100 according to an embodiment of the present invention includes a substrate 10, a vibration element 20, a diaphragm 30 and a connecting rod 40, the substrate 10 includes a base 11 and a support 12, the support 12 extends from one side of the base 11 toward a direction away from the base 11, the base 11 is provided with a first cavity 111 penetrating along a thickness direction thereof, the thickness direction is the extending direction of the support 12, the support 12 is annular and surrounds a second cavity 121 communicating with the first cavity 111, an inner diameter of the first cavity 111 along a direction perpendicular to the thickness direction of the base 11 is smaller than that of the second cavity 121, that is, an outline of the first cavity 111 is smaller than that of the second cavity 121, the vibration element is fixed to the base 11 and at least covers the first cavity 111, one end of the connecting rod 40 is connected to the vibration element 20, and the other end of the connecting rod extends into the second cavity 121 through the first cavity 111 and is fixedly connected to the diaphragm 30, the diaphragm 30 is suspended in the second cavity 121 and is spaced from the inner wall 122 of the support base 12 (i.e. the walls of the second cavity 121).

By arranging the first cavity 111 on the base 11, arranging the second cavity 121 on the support seat 12, connecting the diaphragm 30 with the vibration component 20 through the connecting rod 40, thereby suspending the diaphragm 30 in the second cavity 121, the vibration component 20 is required to be fixed to the base 11, so that the vibration component 20 is hindered by the base 11 when vibrating, only the portion covering the first cavity 111 can vibrate, and the vibration amplitude gradually decreases from the center to the edge of the first cavity 111, resulting in smaller overall amplitude of the vibration component 20, but when vibrating, the vibration component 20 drives the diaphragm 30 to move together through the connecting rod 40, and pushes air through the diaphragm 30 to generate sound, because the diaphragm 30 is suspended in the second cavity 121, and there is a gap between the edge and the inner wall 122 of the support seat 12, the diaphragm 30 performs piston motion along the thickness direction of the base 11, and the motion is not affected by the support seat 12, therefore, the overall amplitude of the support base 12 is larger, and the displacement amounts of the respective portions are the same, so that a larger volume of air can be displaced per unit time, thereby improving the sound output of the MEMS speaker 100.

In this embodiment, the outline of the first cavity 111 is smaller than the outline of the second cavity 121, and the vibrating component 20 and the diaphragm 30 are respectively mounted in the first cavity 111 and the second cavity 121, so that the size of the diaphragm 30 is not limited by the first cavity 111, but only by the second cavity 121, and thus the size of the diaphragm 30 can be set larger than that of the first cavity 111, compared to a scheme in which the vibrating component 20 and the diaphragm 30 are mounted in the same cavity, in a case in which the vibrating component 20 is the same size, the MEMS speaker 100 of this embodiment can be provided with the diaphragm 30 having a larger size, 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 connection 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 at intervals, each first cavity 111 is communicated with the second cavity 121, the number of the first cavities 111, the number of the vibration assemblies 20 and the number of the connecting rods 40 are the same and are in one-to-one correspondence, and each vibration assembly 20 is connected to the same diaphragm 30 through the corresponding connecting rod 40.

By arranging at least two vibration assemblies 20, each vibration assembly 20 is connected with the diaphragm 30 through a corresponding connecting rod 40, all vibration assemblies 20 drive the diaphragm 30 to do piston movement together, the movement stability of the diaphragm 30 is enhanced, and when accidents such as breakage of the connecting rods 40 occur, the MEMS speaker 100 can drive the diaphragm 30 to move through the vibration assemblies 20 to generate sound as long as the MEMS speaker 100 is provided with the connecting rods 40 which connect the diaphragm 30 and the vibration assemblies 20, so that the reliability of the MEMS speaker 100 is improved.

Preferably, the connecting rod 40 is the same size as the two ends to which the vibration assembly 20 and the diaphragm 30 are connected. It can be understood that the two ends of the connecting rod 40 may have different sizes, for example, the size of the end (i.e., the top end) of the connecting rod 40 connected to the vibration assembly 20 may be smaller than the size of the end (i.e., the bottom end) of the connecting rod 40 connected to the diaphragm 30, and the connecting rod 40 is configured to have a special shape with a small top end and a large bottom end, so that the connecting strength between the connecting rod 40 and the diaphragm 30 can be ensured, and the problem that the vibration assembly 20 is affected due to the overlarge connecting rod 40 can be avoided.

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

Preferably, each vibration assembly 20 comprises two actuators 22, the two actuators 22 being fixed to one side of the vibration member 21 remote from the support base 12 and symmetrically arranged on opposite sides of the connecting rod 40.

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

It is to be understood that the number of the drivers 22 on one vibration member 21 is not limited to the above two, and for example, one or more may be possible.

As a modification of the present embodiment, the driver 22 includes a first electrode layer 221 connected to the vibration member 21, a piezoelectric layer 222 provided on a side of the first electrode layer 221 away from the vibration member 21, and a second electrode layer 223 provided on a side of the piezoelectric layer 222 away from the first electrode layer 221.

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

As a modification of the present embodiment, the vibration member 21 includes a vibration diaphragm 211 and a connection beam 212, one side of the vibration diaphragm 211 is connected to the base 11, the other side of the vibration diaphragm 211 extends toward the connection rod 40 and is spaced from the connection rod 40, and the connection beam 212 is connected between the vibration diaphragm 211 and the connection rod 40.

After the vibration of the vibrating diaphragm 211 is generated, the vibration is firstly transmitted to the connecting beam 212, so that the connecting rod 40 moves, and the diaphragm 30 is driven to perform piston movement, and the vibrating diaphragm 211 and the connecting rod 40 are spaced and connected through the connecting beam 212, so that 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 portion of the vibration member 21 and the connection rod 40, the connection beam 212 is made of a flexible thin film material.

It is to be understood that the vibration member 21 is not limited to the above-described form of the diaphragm 211 plus the connection beam 212, and for example, a form of a cantilever beam is also possible.

As a modification of this embodiment, at least two diaphragms 211 are provided, the diaphragms 211 are symmetrically disposed on the periphery of the connecting rod 40, and one driver 22 is disposed on one side of each diaphragm 211 away from the base 11.

Preferably, in this embodiment, each vibration member 21 includes two vibration diaphragms 211 and four connecting beams 212, the two vibration diaphragms 211 are symmetrically disposed on two sides of the connecting rod 40, so as to enhance the motion stability of the diaphragm 30, two connecting beams 212 are connected between each vibration diaphragm 211 and the connecting rod 40, the connecting beams 212 are L-shaped, two ends of each connecting beam 212 are respectively connected with the vibration diaphragm 211 and the connecting rod 40, the vibration diaphragm 211, the two connecting beams 212 connected to the vibration diaphragm 211, and the connecting rod 40 enclose a hollow area 213, and the rigidity of the connecting portion between the vibration member 21 and the connecting rod 40 is further reduced.

It will be appreciated that the shape of the connecting beam 212 is not limited to the L-shape described above, and a serpentine shape, for example, is possible.

As a modification of this embodiment, the diaphragm 211 is suspended in the first cavity 111 and fixed to the base 11 only at a side away from the connecting rod 40.

In this embodiment, the diaphragm 211 is square, two opposite sides of the diaphragm 211 are respectively connected to the base 11 and the connecting beam 212, and the two opposite sides of the diaphragm are spaced from the cavity wall of the first cavity 111, so as to facilitate the vibration of the diaphragm 211.

Preferably, the MEMS speaker 100 is square, the number of the first cavities 111 is four, the four first cavities 111 are arranged in two rows and two columns, that is, the four first cavities 111 are arranged two by two symmetrically, and each first cavity 111 is provided with one vibration component 20 connected with the diaphragm 30 through the connecting rod 40, so as to ensure the stability of the movement of the diaphragm 30.

Referring to fig. 5, an embodiment of the invention further provides a method S100 for manufacturing a MEMS speaker 100, including:

step S10, providing a first silicon wafer 50 having a first surface 51 and a second surface 52, etching a plurality of first cavities 53 extending from the first surface 51 toward the second surface 52 on the first silicon wafer 50, the etched first silicon wafer 50 including a first wafer body 54 provided with the first cavities 53 and first pillars 55 provided in the first cavities 53;

step S20, covering the side of the etched first silicon wafer 50 away from the second surface 52 with a buffer layer 60, the buffer layer 60 being made of silicon oxide;

step S30, providing an SOI wafer 70, where 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, fixing the first silicon layer 71 on the side of the buffer layer 60 away from the first silicon wafer 50 by bonding, removing the first silicon layer 71 and the silicon oxide layer 73, and thinning the first silicon layer 71 to a certain thickness;

step S40, processing the thinned first silicon layer 71 to form a vibration member 21, and disposing a driver 22 on the vibration member 21 to form the vibration 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 body 54, thereby forming the susceptor 11 having the first cavity 111;

step S60, providing a second silicon wafer 80, etching a second cavity 81 on the second silicon wafer 80, wherein the etched second wafer comprises a second wafer body 82 provided with the second cavity 81 and a second convex column 83 arranged in the second cavity 81;

step S70, fixing the etched second silicon wafer 80 on the side of the first silicon wafer 50 away from the buffer layer 60 by bonding, connecting the second wafer main body 82 with the first wafer main body 54 to communicate the first cavity 111 with the second cavity 81, and connecting the second protrusion 83 with the first protrusion 55 to form the connecting bar 40;

step S80, etching a side of the second wafer body 82 away from the first wafer body 54 corresponding to the position of the second cavity 81 to form a third cavity 84, the third cavity 84 and the second cavity 81 being separated by a partition 85 connected to the tie bar 40;

in step S90, the edge of the partition 85 is etched away to form a gap 86 connecting the second cavity 81 and the third cavity 84, so as to obtain the support seat 12 and the diaphragm 30, wherein the support seat 12 encloses a second cavity 121 for accommodating the diaphragm 30.

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 4, the four first cavities 53 are symmetrically distributed in pairs, the number of the second cavities 81 is 1, the size of the second cavities 81 is larger than that of the first cavities 53, the base 11, the first convex column 55, the vibration member 21, the support base 12, the second convex column 83 and the diaphragm 30 are formed by etching, the base 11 and the support base 12 are fixed together in a bonding mode to form the substrate 10, the first convex column 55 and the second convex column 83 are fixed together in a bonding mode to form the connecting rod 40, the vibration member 21 is also fixed to the buffer layer 60 in a bonding mode, namely, the base 11, the support base 12, the vibration member 21, the first convex column 55 and the second convex column 83 are formed into a whole, thereby ensuring the overall strength of the MEMS speaker 100 obtained in this manufacturing method.

Example two:

referring to fig. 6, in comparison with the MEMS speaker 100 provided in the first embodiment, the MEMS speaker 200 provided in the present embodiment includes: the base 11' of the present embodiment is provided with three first cavities 111' at intervals, and the three first cavities 111' are distributed at equal intervals along the length direction of the MEMS speaker 200. It is understood that the number of the first cavities 111' is not limited to three, and for example, one, two or other numbers of a plurality are also possible.

Example three:

referring to fig. 7, in comparison with the MEMS speaker 100 provided in the first embodiment, the MEMS speaker 300 provided in the present embodiment includes: the MEMS speaker 300 of this embodiment is cylindrical, and the vibrating member 21 ″ is in the form of a cantilever beam, the base 11 ″ has three first cavities 111 opened thereon, the three first cavities 111 "are equally spaced along the circumference of the base 11", and an included angle between any two adjacent cantilever beams is 120 °. It is understood that the number of the first cavities 111 "is not limited to three, and for example, one, two or other numbers of a plurality are also possible.

While the foregoing is directed to embodiments of the present invention, it will be understood by those skilled in the art that various changes may be made without departing from the spirit and scope of the invention.

Claims

1. An MEMS loudspeaker is characterized by comprising a substrate, a vibration assembly, a diaphragm and a connecting rod, wherein the substrate comprises a base and a supporting seat extending from one side of the base, a first cavity penetrates through the base along the thickness direction of the base, the supporting seat is annular and encloses to form a second cavity communicated with the first cavity, and the inner diameter of the first cavity along the direction perpendicular to the thickness direction is smaller than that of the second cavity; the vibration component is fixed in the basement and at least cover part the first cavity, the one end of connecting rod with the vibration component is connected, the other end warp the first cavity extends to the second cavity and with the diaphragm is connected, the diaphragm hang locate in the second cavity and with the inner wall interval setting of supporting seat.

2. The MEMS speaker as claimed in claim 1, wherein the base has at least two first cavities spaced apart from each other, each first cavity is communicated with the second cavity, the first cavities correspond to the vibrating assemblies and the connecting rods one to one, and the vibrating assemblies are connected to the same diaphragm through the corresponding connecting rods.

3. The MEMS loudspeaker of claim 1, wherein the vibration assembly includes a vibration member disposed on a side of the base remote from the support base and a driver disposed on the vibration member, the vibration member covering at least a portion of the first cavity.

4. The MEMS loudspeaker of claim 3, wherein each of the vibration assemblies comprises two of the drivers, the two drivers being fixed to a side of the vibration member away from the support base and symmetrically disposed on opposite sides of the connecting rod.

5. The MEMS speaker as recited in claim 3, wherein the driver includes a first electrode layer connected to the vibration member, a piezoelectric layer provided on a side of the first electrode layer remote from the vibration member, and a second electrode layer provided on a side of the piezoelectric layer remote from the first electrode layer.

6. The MEMS speaker as recited in claim 3, wherein the vibration member includes a diaphragm and a connection beam, one side of the diaphragm is connected to the base, the other side of the diaphragm extends toward and is spaced apart from the connection rod, and the connection beam is connected between the diaphragm and the connection rod.

7. The MEMS loudspeaker of claim 6, wherein the diaphragms are provided with at least two diaphragms symmetrically disposed on the periphery of the connecting rod, and one driver is provided on a side of each diaphragm away from the base.

8. The MEMS speaker of claim 6, wherein the connecting beam is L-shaped or serpentine.

9. The MEMS speaker of claim 6, wherein the diaphragm is suspended from the first cavity and secured to the base only on a side away from the connecting bar.

10. The MEMS speaker as recited in claim 2, wherein the MEMS speaker is square or circular, and the connecting rods are equally spaced.

11. A method of manufacturing a MEMS speaker, comprising: