A MEMS speaker

Abstract

The utility model provides MEMS loudspeaker. The utility model discloses MEMS loudspeaker includes at least one piezoelectric driver, and multiple piezoelectric driver array arrangement, piezoelectric driver includes the substrate that is enclosed and is formed with cavity, the drive structure that is stacked in the substrate one side along the vibration direction and covers the cavity, and the vibration structure that is stacked in the drive structure one side away from the substrate along the vibration direction and covers at least part drive structure, MEMS loudspeaker is equipped with the slit along the vibration direction through in both sides along the first direction, and the slit is at least formed in the drive structure, and the projection of slit along the vibration direction falls into the cavity, the width of slit is between 0~10um, and the first direction is orthogonal with the vibration direction arrangement. Set up the slit, can relax the displacement restriction to vibration structure, promote vibration displacement to can improve energy conversion efficiency, set up the width of slit between 0~10um, prevent the sound short circuit, guarantee the sound effect. Multiple piezoelectric driver array sets up, further improves the performance of MEMS loudspeaker.

Description

[Technical Field]

[0001] This utility model belongs to the field of sound-generating device technology, and in particular relates to a MEMS loudspeaker. [Background Technology]

[0002] MEMS speakers, as one of the main components of mobile terminals such as mobile phones, include a driving structure and a vibration structure. The driving structure drives the vibration structure to vibrate and produce sound.

[0003] Compared with traditional loudspeakers, MEMS loudspeakers have advantages such as good consistency, low power consumption, small size and low price. However, in MEMS loudspeakers of related technologies, the vibration structure usually adopts a full-coverage mode, which makes it impossible for the vibration structure to be completely decoupled from the outer frame, resulting in low energy conversion efficiency.

[0004] Therefore, it is necessary to provide a new MEMS loudspeaker. [Utility Model Content]

[0005] The purpose of this invention is to provide a MEMS loudspeaker that can relax the displacement restrictions on the vibrating structure, increase the vibration displacement, and thus improve the energy conversion efficiency.

[0006] The technical solution of this utility model is as follows:

[0007] A MEMS loudspeaker includes at least one piezoelectric actuator, and a plurality of the piezoelectric actuators are arranged in an array. The piezoelectric actuator includes a substrate enclosing a cavity, a driving structure stacked on one side of the substrate along the vibration direction and covering the cavity, and a vibration structure stacked on the side of the driving structure opposite to the substrate along the vibration direction and covering at least a portion of the driving structure. The MEMS loudspeaker has slits extending through the vibration direction on both sides along a first direction. The slits are formed at least in the driving structure, and the projection of the slits along the vibration direction falls into the cavity. The width of the slits is between 0 and 10 μm. The first direction is orthogonal to the vibration direction.

[0008] Furthermore, the projection of the vibrating structure along the vibration direction coincides with the projection of the driving structure along the vibration direction, and the slit extends from the vibrating structure to the driving structure along the vibration direction.

[0009] Furthermore, the slits are formed in the drive structure, and the projection of the vibrating structure along the vibration direction falls between the two slits.

[0010] Furthermore, the MEMS loudspeaker includes two piezoelectric actuators that are attached to each other along a second direction, the second direction being orthogonal to the vibration direction and orthogonal to the first direction; wherein the projection of the vibration structure of one piezoelectric actuator along the vibration direction coincides with the projection of the driving structure along the vibration direction, and the slit extends from the vibration structure to the driving structure along the vibration direction; the slit of the other piezoelectric actuator is formed in the driving structure, and the projection of the vibration structure along the vibration direction falls between the two slits.

[0011] Furthermore, the substrate has four sidewalls for enclosing the cavity, wherein, along the second direction, one sidewall of one of the piezoelectric actuators is attached to one sidewall of the other piezoelectric actuator.

[0012] Furthermore, the driving structure includes a first electrode layer stacked on the side of the substrate facing the vibration structure, a piezoelectric thin film stacked on the side of the first electrode layer facing away from the substrate, and a second electrode layer stacked between the piezoelectric thin film and the vibration structure.

[0013] Furthermore, the Young's modulus of the vibrating structure is smaller than that of the piezoelectric film.

[0014] Furthermore, the Young's modulus of the vibrating structure is 1 to 10 MPa.

[0015] Furthermore, the vibrating structure includes at least one organic diaphragm.

[0016] Furthermore, the driving structure has a plurality of openings that penetrate the driving structure along the vibration direction and communicate with the cavity, the plurality of openings are arranged at intervals, and the vibration structure covers the openings.

[0017] Furthermore, the opening structure includes a first opening, which includes a first branch hole extending along a first direction and a second branch hole extending along a second direction, wherein the first branch hole and the second branch hole are intersecting and connected.

[0018] Furthermore, the opening structure includes a second opening, which includes two third sub-holes extending along a first direction and spaced apart along a second direction, and a fourth sub-hole whose two ends are respectively connected to the third sub-holes.

[0019] The beneficial effects of this invention are as follows: Along the vibration direction, the substrate, driving structure, and vibration structure are sequentially arranged. The substrate has a cavity to provide vibration space; the driving structure can cause the vibration structure to deform, thus driving air vibration and achieving sound generation; furthermore, by integrating the vibration structure and driving structure onto the substrate, miniaturization can be achieved. Additionally, slits extending along the vibration direction are provided on both sides of the MEMS speaker, and the projection of the slits along the vibration direction falls into the cavity. This relaxes the displacement restrictions on the vibration structure, increases vibration displacement, and thus improves energy conversion efficiency. Simultaneously, the slit width is set between 0 and 10 μm, i.e., the slit size in the first direction is limited to between 0 and 10 μm, thus preventing acoustic short circuits and ensuring sound quality. Furthermore, the MEMS speaker can have at least one piezoelectric driver. When the MEMS speaker has multiple piezoelectric drivers, an array of multiple piezoelectric drivers can be arranged, further improving the performance of the MEMS speaker. [Attached Image Description]

[0020] Figure 1 This is a schematic diagram of the MEMS speaker in Embodiment 1 of this utility model from a first-view perspective;

[0021] Figure 2 For along Figure 1 A cross-sectional view along the AA direction;

[0022] Figure 3 This is a schematic diagram of the MEMS speaker in Embodiment 1 of this utility model from a second perspective.

[0023] Figure 4 This is an exploded view of the MEMS loudspeaker in Embodiment 1 of this utility model;

[0024] Figure 5 This is a schematic diagram of the MEMS speaker in Embodiment 2 of this utility model from a first-view perspective;

[0025] Figure 6 For along Figure 5 A cross-sectional view along the AA direction;

[0026] Figure 7 This is a schematic diagram of the MEMS speaker in Embodiment 2 of this utility model from a second perspective;

[0027] Figure 8 This is an exploded view of the MEMS loudspeaker in Embodiment 2 of this utility model;

[0028] Figure 9 This is a schematic diagram of the MEMS loudspeaker in Embodiment 3 of this utility model;

[0029] Figure 10 For along Figure 9 A cross-sectional view along the AA direction;

[0030] Figure 11 This is an exploded view of the MEMS loudspeaker in Embodiment 3 of this utility model.

[0031] In the accompanying drawings, the reference numerals denote: 1, piezoelectric actuator; 11, substrate; 110, cavity; 111, sidewall; 12, driving structure; 121, first electrode layer; 122, piezoelectric thin film; 123, second electrode layer; 120, opening structure; 1201, first opening; 1201A, first sub-aperture; 1201B, second sub-aperture; 1202, second opening; 1202A, third sub-aperture; 1202B, fourth sub-aperture; 13, vibrating structure; 14, slit; 15, silicon thin film.

Detailed Implementation Methods

[0032] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "circumferential", "radial", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] Please see Figures 1 to 11A MEMS loudspeaker includes at least one piezoelectric actuator 1, and an array of multiple piezoelectric actuators 1 are arranged. The piezoelectric actuator 1 includes a substrate 11 enclosing a cavity 110, a driving structure 12 stacked on one side of the substrate 11 along the vibration direction and covering the cavity 110, and a vibrating structure 13 stacked on the side of the driving structure 12 away from the substrate 11 along the vibration direction and covering at least part of the driving structure 12. The MEMS loudspeaker has slits 14 extending through the vibration direction on both sides along a first direction. The slits 14 are formed at least in the driving structure 12, and the projection of the slits 14 along the vibration direction falls into the cavity 110. The width of the slits 14 is between 0 and 10 μm. The first direction is orthogonal to the vibration direction.

[0036] In this embodiment of the invention, the substrate 11, the driving structure 12, and the vibration structure 13 are sequentially arranged along the vibration direction. The substrate 11 has a cavity 110, which provides a vibration space. The driving structure 12 can drive the vibration structure 13 to deform and vibrate the air, thereby achieving a sound effect. Furthermore, by integrating the vibration structure 13 and the driving structure 12 onto the substrate 11, miniaturization can be achieved. In addition, slits 14 extending along the vibration direction are provided on both sides of the MEMS speaker, and the projection of the slits 14 along the vibration direction falls into the cavity 110. This relaxes the displacement restriction on the vibration structure 13, increases the vibration displacement, and thus improves the energy conversion efficiency. At the same time, the width of the slits 14 is set between 0 and 10 μm, that is, the size of the slits 14 in the first direction is limited to between 0 and 10 μm. This prevents acoustic short circuits and ensures the sound effect. In addition, a MEMS loudspeaker can have at least one piezoelectric driver 1. When there are multiple piezoelectric drivers 1 on the MEMS loudspeaker, the array of multiple piezoelectric drivers 1 can be arranged, thereby further improving the performance of the MEMS loudspeaker.

[0037] It should be noted that in this utility model, if the first direction can be the length direction of the substrate 11, then the second direction can be the width direction of the substrate 11; and vice versa.

[0038] In some embodiments, see Figures 1 to 4 The projection of the vibrating structure 13 along the vibration direction coincides with the projection of the driving structure 12 along the vibration direction, and the slit 14 extends from the vibrating structure 13 to the driving structure 12 along the vibration direction.

[0039] Specifically, both the vibration structure 13 and the driving structure 12 can be layered square structures. In the vibration direction, the vibration structure 13 and the driving structure 12 can completely overlap, so that the outer edge of the vibration structure 13 and the outer edge of the driving structure 12 are flush. At this time, the slit 14 can include a first slit 14 formed in the vibration structure 13 and a second slit 14 formed in the driving structure 12. The first slit 14 and the second slit 14 coincide in the vibration direction, and the projection of the first slit 14 and the second slit 14 in the vibration direction falls into the cavity 110. This allows the piezoelectric actuator 1 to form slits 14 that penetrate along the vibration direction on both sides of the first direction. By setting the slits 14, the displacement restriction on the vibration structure 13 can be relaxed, the vibration displacement can be increased, and the energy conversion efficiency can be improved.

[0040] In some embodiments, see Figures 5 to 8 The slit 14 is formed in the driving structure 12, and the projection of the vibration structure 13 along the vibration direction falls between the two slits 14.

[0041] Specifically, the projection of the vibrating structure 13 along the vibration direction can only cover a portion of the driving structure 12. Furthermore, the extension length of the vibrating structure 13 along the first direction can be the distance between the two slits 14 along the first direction or less. In this case, the slits 14 are formed only in the driving structure 12, creating slits 14 that penetrate along the vibration direction. One side of the slit 14 along the vibration direction connects to the cavity 110, and the other side connects to the outer edge of the vibrating structure 13. Thus, the displacement restriction on the vibrating structure 13 can be relaxed through the slits 14, increasing the vibration displacement and thereby improving energy conversion efficiency. Additionally, the size of the vibrating structure 13 can be smaller than the size of the driving structure 12, still allowing the driving structure 12 to drive the vibrating structure 13 to vibrate and produce sound. Moreover, because the vibrating structure 13 is smaller, it can produce a better driving effect, further improving the sound production effect.

[0042] In some embodiments, see Figures 9 to 11 The MEMS loudspeaker includes two piezoelectric actuators 1 attached together along a second direction, which is orthogonal to the vibration direction and also orthogonal to the first direction. The projection of the vibration structure 13 of one piezoelectric actuator 1 along the vibration direction coincides with the projection of the drive structure 12 along the vibration direction, and a slit 14 extends from the vibration structure 13 to the drive structure 12 along the vibration direction. The slit 14 of the other piezoelectric actuator 1 is formed in the drive structure 12, and the projection of the vibration structure 13 along the vibration direction falls between the two slits 14.

[0043] Specifically, the MEMS loudspeaker may include two piezoelectric drivers 1, which are arranged sequentially along the second direction. The vibration structures 13 of the two piezoelectric drivers 1 may be different. The vibration structure 13 of one piezoelectric driver 1 may completely coincide with the corresponding driving structure 12 in the vibration direction, while the projection of the vibration structure 13 of the other piezoelectric driver 1 along the vibration direction may not completely cover the driving structure 12. In this way, the two piezoelectric drivers 1 can have different sound production effects. By combining two piezoelectric drivers 1 with different vibration structures 13, different suitable loudnesses can be flexibly adjusted to meet various practical needs.

[0044] Furthermore, the substrate 11 has four sidewalls 111 for enclosing the cavity 110, and along the second direction, one sidewall 111 of one piezoelectric actuator 1 is attached to one sidewall 111 of another piezoelectric actuator 1.

[0045] Specifically, the substrates 11 and driving structures 12 of the two piezoelectric actuators 1 are the same size. The substrate 11 is quadrilateral with four sidewalls 111, wherein two sidewalls 111 are spaced apart along a first direction, and the other two sidewalls 111 are spaced apart along a second direction. The four sidewalls 111 enclose a cavity 110. In the second direction, one sidewall 111 of one piezoelectric actuator 1 and one sidewall 111 of the other piezoelectric actuator 1 are attached together, thereby realizing the parallel arrangement of the two piezoelectric actuators 1 in the second direction. This allows the two slits 14 of one piezoelectric actuator 1 to be spaced apart along the first direction, and the two slits 14 of the other piezoelectric actuator 1 to also be spaced apart along the first direction. In this way, the displacement restriction on the vibration structure 13 of the two piezoelectric actuators 1 can be relaxed, the vibration displacement can be increased, and the energy conversion efficiency can be improved.

[0046] Furthermore, in some embodiments, the driving structure 12 includes a first electrode layer 121 stacked on the side of the substrate 11 facing the vibration structure 13, a piezoelectric thin film 122 stacked on the side of the first electrode layer 121 facing away from the substrate 11, and a second electrode layer 123 stacked between the piezoelectric thin film 122 and the vibration structure 13.

[0047] Specifically, along the vibration direction, the loudspeaker sequentially includes a substrate 11, a first electrode layer 121, a piezoelectric film 122, a second electrode layer 123, and a vibration structure 13. Under the action of the first electrode layer 121 and the second electrode layer 123, the piezoelectric film 122 undergoes bending deformation, thereby driving the vibration structure 13 to vibrate and produce sound.

[0048] Furthermore, it is understood that since the slit 14 is formed at least on the driving structure 12, which may include a first electrode layer 121, a piezoelectric film 122, and a second electrode layer 123, and the projections of the first electrode layer 121, the piezoelectric film 122, and the second electrode layer 123 in the vibration direction coincide, not only will a portion of the piezoelectric film 122 form the slit 14, but the first electrode layer 121 and the second electrode layer 123 will also form a portion of the slit 14, allowing the slit 14 to penetrate along the vibration direction. This relaxes the displacement restriction on the vibration structure 13, increases the vibration displacement, and thereby improves the energy conversion efficiency.

[0049] Furthermore, in some specific embodiments, a silicon thin film 15 may be disposed between the substrate 11 and the first electrode layer 121. At the same time, an insulating layer may be disposed between the substrate 11 and the silicon thin film 15 to achieve electrical isolation between the substrate 11 and the silicon layer. The silicon thin film 15 may be used as a vibration layer, and it will also generate sound by deforming and vibrating under the action of the driving structure 12 to enhance the sound generation effect.

[0050] Furthermore, in some embodiments, the Young's modulus of the vibrating structure 13 is less than the Young's modulus of the piezoelectric film 122.

[0051] Specifically, the Young's modulus of the vibrating structure 13 is set to be smaller than that of the piezoelectric film 122, so that the vibrating structure 13 has a strong ability to elastically deform, thereby increasing the vibration displacement and improving the acoustic performance of the MEMS loudspeaker.

[0052] Furthermore, in some embodiments, the Young's modulus of the vibrating structure 13 is 1 to 10 MPa.

[0053] Specifically, the Young's modulus of the vibrating structure 13 can be set to 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 MPa, etc., while the Young's modulus of the piezoelectric film 122 is usually 70 GPa. In this embodiment of the invention, the Young's modulus of the vibrating structure 13 is limited to between 1 and 10 MPa, so that the Young's modulus of the vibrating structure 13 is much smaller than that of the piezoelectric film 122. This allows the vibrating structure 13 to have a stronger ability to elastically deform, thereby better improving the vibration displacement and making the acoustic performance of the MEMS loudspeaker more outstanding.

[0054] Furthermore, in some embodiments, the vibrating structure 13 includes at least one organic diaphragm. Specifically, the vibrating structure 13 may be composed of at least one organic diaphragm, and multiple organic diaphragms may be stacked sequentially along the vibration direction. By combining multiple organic diaphragms, the deformation effect of the vibrating structure 13 can be enhanced, thereby enhancing the sound production effect.

[0055] Furthermore, in some embodiments, the drive structure 12 has a plurality of opening structures 120 that penetrate the drive structure 12 along the vibration direction and communicate with the cavity 110. The plurality of opening structures 120 are arranged at intervals, and the vibration structure 13 covers the opening structures 120.

[0056] Specifically, a plurality of opening structures 120 can be formed on the driving structure 12, and the vibration structure 13 is disposed on the side of the driving structure 12 away from the substrate 11. Regardless of whether the vibration structure 13 completely covers the driving structure 12 or covers part of the driving structure 12, the vibration structure 13 must cover the opening structure 120. The enclosure of the vibration structure 13 and the opening structure 120 is equivalent to opening a blind hole in the piezoelectric actuator 1. The opening of the hole faces the cavity 110 and is connected to the cavity 110. By setting a plurality of opening structures 120 on the driving structure 12, the driving structure 12 can obtain different degrees of vibration displacement, thereby selectively generating sound of different intensities.

[0057] It should be noted that the fact that the projection of the vibrating structure 13 along the vibration direction coincides with the projection of the driving structure 12 along the vibration direction only means that the vibrating structure 13 completely covers the driving structure 12 and the edges are completely aligned. However, it does not mean that the projections of the vibrating structure 13 and the driving structure 12 are exactly the same. Therefore, when the driving structure 12 has an opening structure 120, the vibrating structure 13 does not need to have an opening structure 120. Instead, the vibrating structure 13 is placed on the opening structure 120 to achieve different sound effects.

[0058] Additionally, it is understood that the driving structure 12 has an opening structure 120, and the driving structure 12 may include a first electrode layer 121, a piezoelectric film 122, and a second electrode layer 123. Therefore, the first electrode layer 121 has a portion of the opening structure 120, the piezoelectric film 122 has a portion of the opening structure 120, and the second electrode layer 123 has a portion of the opening structure 120, which together form the opening structure 120 of the driving structure 12, such that the opening structure 120 penetrates the driving structure 12 along the vibration direction.

[0059] Furthermore, it should be noted that in some specific embodiments, a silicon thin film 15 is also provided between the substrate 11 and the first electrode layer 121. The silicon thin film 15 is used as a vibration layer. At the same time, an insulating layer is provided between the substrate 11 and the silicon thin film 15. In this case, a hole-like structure corresponding to the opening structure 120 of the driving structure 12 can also be provided between the silicon thin film 15 and the insulating layer, so that the opening structure 120 can penetrate and connect the cavity 110.

[0060] In some embodiments, the opening structure 120 includes a first opening 1201, which includes a first branch opening 1201A extending along a first direction and a second branch opening 1201B extending along a second direction, with the first branch opening 1201A and the second branch opening 1201B intersecting and communicating. Specifically, the opening structure 120 can be the first opening 1201, which can be in a cross shape, allowing the vibrating structure 13 to obtain different degrees of vibration displacement and selectively generate sounds of different intensities. Understandably, in some embodiments, the first opening 1201 near the first slit 14 can only be in a straight line shape, i.e., excluding the second branch opening 1201B, and directly communicate with the slit 14. Specifically, this can be determined based on the arrangement of the first opening 1201 and the distance between the two slits 14.

[0061] In some embodiments, the opening structure 120 includes a second opening 1202, which includes two third branch holes 1202A extending along a first direction and spaced apart along a second direction, and a fourth branch hole 1202B whose two ends are respectively connected to the third branch holes 1202A. Specifically, the opening structure 120 can be the second opening 1202, which can be in the shape of an "I". Similarly, this allows the vibrating structure 13 to obtain different degrees of vibration displacement and selectively generate sounds of different intensities.

[0062] In some embodiments, a portion of the opening structure 120 can be a first opening 1201, and another portion of the opening structure 120 can be a second opening 1202, so that a plurality of first openings 1201 and a plurality of second openings 1202 can be formed on the driving structure 12, so that the driving structure 12 can form a variety of different forms of hole structures, thereby obtaining more different degrees of vibration displacement and more selectively generating sounds of different intensities.

[0063] Furthermore, in some embodiments, a plurality of first openings 1201 and a plurality of second openings 1202 can be arranged sequentially along a first direction, and the first branch opening 1201A of the first opening 1201 can be partially disposed between two adjacent third branch openings 1202A. In this way, the arrangement of the first openings 1201 and the second openings 1202 can be more regular and compact, thereby allowing for better control of the sound effect.

[0064] The above description is merely an embodiment of this utility model. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of this utility model, but these improvements all fall within the protection scope of this utility model.

Claims

1. A MEMS loudspeaker, characterized in that, It includes at least one piezoelectric actuator, and multiple piezoelectric actuator arrays are arranged together; The piezoelectric actuator includes a substrate enclosing a cavity, a drive structure stacked on one side of the substrate along the vibration direction and covering the cavity, and a vibration structure stacked on the side of the drive structure opposite to the substrate along the vibration direction and covering at least part of the drive structure. The MEMS loudspeaker has slits extending through the vibration direction on both sides along the first direction. The slits are formed at least in the driving structure, and the projection of the slits along the vibration direction falls into the cavity. The width of the slits is between 0 and 10 μm. The first direction is orthogonal to the vibration direction.

2. The MEMS loudspeaker according to claim 1, characterized in that, The projection of the vibrating structure along the vibration direction coincides with the projection of the driving structure along the vibration direction, and the slit extends from the vibrating structure to the driving structure along the vibration direction; Alternatively, the slits are formed in the drive structure, and the projection of the vibrating structure along the vibration direction falls between the two slits.

3. The MEMS loudspeaker according to claim 1, characterized in that, The MEMS loudspeaker includes two piezoelectric actuators that are fitted together along a second direction, the second direction being orthogonal to the vibration direction and orthogonal to the first direction; The projection of the vibration structure of one of the piezoelectric actuators along the vibration direction coincides with the projection of the driving structure along the vibration direction, and the slit extends from the vibration structure to the driving structure along the vibration direction. Another slit of the piezoelectric actuator is formed in the drive structure, and the projection of the vibrating structure along the vibration direction falls between the two slits.

4. The MEMS loudspeaker according to claim 3, characterized in that, The substrate has four sidewalls for enclosing the cavity, and along a second direction, one sidewall of one of the piezoelectric actuators is attached to one sidewall of the other piezoelectric actuator.

5. The MEMS loudspeaker according to claim 1, characterized in that, The driving structure includes a first electrode layer stacked on the side of the substrate facing the vibration structure, a piezoelectric thin film stacked on the side of the first electrode layer facing away from the substrate, and a second electrode layer stacked between the piezoelectric thin film and the vibration structure.

6. The MEMS loudspeaker according to claim 5, characterized in that, The Young's modulus of the vibrating structure is less than that of the piezoelectric film.

7. The MEMS loudspeaker according to claim 5, characterized in that, The Young's modulus of the vibrating structure is 1 to 10 MPa.

8. The MEMS loudspeaker according to claim 5, characterized in that, The vibrating structure includes at least one organic diaphragm.

9. The MEMS loudspeaker according to claim 1, characterized in that, The driving structure has a plurality of openings that penetrate the driving structure along the vibration direction and connect to the cavity. The plurality of openings are arranged at intervals, and the vibration structure covers the openings.

10. The MEMS loudspeaker according to claim 9, characterized in that, The opening structure includes a first opening, the first opening including a first branch hole extending along a first direction and a second branch hole extending along a second direction, the first branch hole and the second branch hole being intersecting and communicating; And / or, The opening structure includes a second opening, which includes two third sub-holes extending along a first direction and spaced apart along a second direction, and a fourth sub-hole whose two ends are respectively connected to the third sub-holes.

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