JP2023056253A - transducer - Google Patents

Abstract

To provide a transducer capable of preventing a damage of a vibration film by relaxing a stress applied to the vibration film.SOLUTION: A transducer 1 comprises: a piezo electric element 3 including a piezoelectric film 11, an upper electrode 13 laminated on the upper surface of the piezoelectric film 11, and a lower electrode 15 laminated on the lower surface of the piezoelectric film 11; and a vibration film 21 supported by a film supporting part 23 having a hollow part 25 formed inside. The piezo electric element 3 is laminated on the upper surface of the vibration film 21, and a plurality of holes 31 or slits 33 penetrating from the surface of the upper electrode 13 to at least the piezoelectric film 11 are formed.SELECTED DRAWING: Figure 2

Description

The present invention relates to transducers.

Conventionally known are transducers for transmitting or receiving sound waves or ultrasound waves. Transducers are used, for example, as speakers that transmit sound waves, and are mounted on earphones, wearable terminals, and the like.

For example, Patent Literature 1 discloses a sound generator suitable for earphones. This sound generator includes a coil that generates a magnetic field, and a magnet that interacts with the magnetic field generated by the coil to vibrate a diaphragm.

A speaker using a coil and a magnet requires a current to flow through the coil in order to generate a magnetic field, resulting in high power consumption. Therefore, a speaker using a piezoelectric element configured by sandwiching a piezoelectric film from both sides with a pair of electrodes has also attracted attention (see, for example, Patent Document 2). This type of speaker is manufactured using MEMS (Micro Electro Mechanical Systems), which is a semiconductor manufacturing technology that realizes microfabrication.

JP 2018-170592 A JP 2012-105170 A

Piezoelectric MEMS transducers have a laminated structure consisting of a piezoelectric film that deforms when an electric field is applied and a base made of silicon or the like that does not deform. It is a micro-mechanism that converts electric field and motion. However, when an electric field is applied to move the laminated film, the film that is about to contract in the lateral direction and the film that is not contracting pull each other, so stress is applied within and between the layers. . When this stress is repeated or during resonance, cracks or the like may occur between crystals, between crystal grains, or at crystal defects due to the stress resulting from vibration, which may damage the vibrating membrane.

Accordingly, the present disclosure has been made in view of such problems, and an object thereof is to provide a transducer that can prevent damage to the vibrating membrane by relieving the stress applied to the vibrating membrane.

In order to solve such problems, a transducer according to the present disclosure includes a piezoelectric element including a piezoelectric film, an upper electrode laminated on the upper surface of the piezoelectric film, and a lower electrode laminated on the lower surface of the piezoelectric film. , and a vibrating membrane supported by a membrane support portion having a hollow portion formed therein. A piezoelectric element is laminated on the upper surface of the vibrating film, and a plurality of holes or slits penetrating from the surface of the upper electrode to at least the piezoelectric film are formed.

According to the present disclosure, it is possible to provide a transducer capable of relieving stress applied to the vibrating membrane and preventing damage to the vibrating membrane.

FIG. 1 is a top view showing the structure of the transducer according to the first embodiment. FIG. 2 is a cross-sectional view of the transducer according to the first embodiment as viewed in the arrow direction of FIG. 3A is an enlarged cross-sectional view showing an enlarged cross-sectional structure of the piezoelectric element portion shown in FIG. 2. FIG. FIG. 3B is an enlarged cross-sectional view showing the cross-sectional structure of the piezoelectric element when the shape of the hole is changed. FIG. 3C is an enlarged cross-sectional view showing an enlarged cross-sectional structure of the piezoelectric element portion when the shape of the hole is changed. FIG. 4 is a top view showing a modification of the arrangement of holes in the transducer according to the first embodiment. FIG. 5 is a top view showing the arrangement of slits in the transducer according to the first embodiment. FIG. 6 is a top view showing the structure of the transducer according to the second embodiment. FIG. 7 is a cross-sectional view of the transducer according to the second embodiment as viewed in the arrow direction of FIG. FIG. 8 is a top view showing the arrangement of slits in the transducer according to the second embodiment. FIG. 9 is a top view showing a modification of the arrangement of slits in the transducer according to the second embodiment. FIG. 10 is a top view showing a modification of the structure of the transducer according to the second embodiment. FIG. 11 is a cross-sectional view of the transducer according to the second embodiment taken along the arrow direction in FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same parts are denoted by the same reference numerals, and detailed description thereof is omitted.

[First embodiment]
The configuration of a transducer 1 according to this embodiment will be described with reference to FIGS. 1 to 3. FIG. A transducer 1 according to this embodiment is mainly composed of a piezoelectric element 3 and a film body 5 . In the following description, the vertical direction is defined based on the state of the transducer 1 shown in FIG. 2, but the direction in which the transducer 1 is used is not limited.

The piezoelectric element 3 includes a piezoelectric film 11, an upper electrode 13 laminated on the upper surface of the piezoelectric film 11, and a lower electrode 15 laminated on the lower surface of the piezoelectric film 11. The piezoelectric element 3 is laminated on the upper surface of the vibrating film 21 to be described later. It is The piezoelectric film 11, the upper electrode 13, and the lower electrode 15 have a shape corresponding to the shape of the vibrating film 21, and have a circular shape in the example shown in FIGS.

The piezoelectric film 11 is composed of, for example, a lead zirconate titanate (PZT) film. The piezoelectric film 11 can be made of aluminum nitride (AlN), zinc oxide (ZnO), lead titanate (PbTiO3), or the like, in addition to lead zirconate titanate.

Each of the upper electrode 13 and the lower electrode 15 is formed of a conductive metal thin film such as platinum, molybdenum, iridium, or titanium. The upper electrode 13 is located above the piezoelectric film 11 and is connected to an electrode pad 13a, which is a circuit pattern for applying a driving voltage to the upper electrode 13. As shown in FIG. The lower electrode 15 is located below the piezoelectric film 11 and is connected to an electrode pad 15a, which is a circuit pattern for applying a driving voltage to the lower electrode 15. As shown in FIG.

The membrane body 5 is composed of a vibrating membrane 21 and a membrane supporting portion 23 . The film body 5 is made of silicon (Si), for example. By etching the lower surface side of the membrane body 5, the vibrating membrane 21 and the membrane supporting portion 23 are integrally formed.

The vibrating film 21 is a membrane type vibrating film. in the vertical direction of the paper)). The vibrating membrane 21 has a circular shape when viewed in a plane parallel to the vibrating membrane 21 .

The membrane support portion 23 has a cylindrical inner peripheral surface forming a cavity (hollow portion) 25 . The vibrating membrane 21 is connected to the inner peripheral surface of the membrane supporting portion 23 over the entire circumference so that the vibrating membrane 21 is inscribed therein. The vibrating membrane 21 is connected to the upper end side of the membrane supporting portion 23 , and the upper side of the cavity 25 is closed by the vibrating membrane 21 .

Here, a plurality of holes 31 are formed in the transducer 1 as shown in FIG. The plurality of holes 31 penetrate from the surface of the upper electrode 13 to the piezoelectric film 11 as shown in FIG. 3A. Since the piezoelectric film 11 contracts when a drive voltage is applied to the upper electrode 13 and the lower electrode 15, a plurality of holes 31 are formed in the piezoelectric film 11 in order to relax the stress of the piezoelectric film 11 that actually contracts. must have been Therefore, by penetrating the plurality of holes 31 from the surface of the upper electrode 13 to the piezoelectric film 11, the plurality of holes 31 are formed in the piezoelectric film 11 that actually contracts, so that the stress caused by the contraction of the piezoelectric film 11 can be relaxed. I have to. As a result, the stress applied to the vibrating membrane 21 can be relaxed, and damage to the vibrating membrane 21 can be prevented.

Moreover, as shown in FIG. 3B, a plurality of holes 31 may penetrate from the surface of the upper electrode 13 to the lower electrode 15 . As a result, the stress caused by the contraction of the piezoelectric film 11 can be relaxed, and the stress of the lower electrode 15 can also be relaxed. As a result, the stress applied to the vibrating membrane 21 can be relaxed, and damage to the vibrating membrane 21 can be prevented.

Further, as shown in FIG. 3C, multiple holes 31 may penetrate from the surface of the upper electrode 13 to the vibrating membrane 21 . As a result, the hole 31 can be formed directly in the vibrating film 21, so that the stress caused by the contraction of the piezoelectric film 11 can be relaxed, and the stress applied to the vibrating film 21 can also be directly relaxed. Therefore, damage to the vibrating membrane 21 can be prevented more effectively. Thus, the plurality of holes 31 penetrate from the surface of the upper electrode 13 to at least the piezoelectric film 11 .

Further, when the vibrating membrane 21 is circular, the plurality of holes 31 are arranged point-symmetrically with respect to the center of the vibrating membrane 21 as shown in FIG. By arranging the holes 31 point-symmetrically, the plurality of holes 31 can be arranged linearly from the center of the vibrating membrane 21 toward the outer peripheral portion of the vibrating membrane 21 . In the vibrating membrane 21, the central portion is displaced, whereas the outer peripheral portion is connected to the membrane supporting portion 23 and thus fixed. Therefore, the stress applied to the vibrating membrane 21 acts by tension between the center and the outer peripheral portion of the vibrating membrane 21 . Therefore, if a plurality of holes 31 are arranged point-symmetrically and arranged in a straight line from the center of diaphragm 21 toward the outer circumference, the stress acting between the center and the outer circumference of diaphragm 21 can be reduced. can be effectively mitigated.

The plurality of holes 31 may be arranged concentrically with respect to the center of the vibrating membrane 21, as shown in FIG. In this case also, the holes 31 can be arranged linearly from the center of the vibrating membrane 21 toward the outer periphery, so that the stress acting between the center and the outer periphery of the vibrating membrane 21 can be effectively relieved. be able to.

Also, instead of the plurality of holes 31, a plurality of slits 33 may be formed as shown in FIG. As a result, the slit 33 can be arranged from the center of the vibrating membrane 21 toward the outer periphery, so that the stress acting between the center and the outer periphery of the vibrating membrane 21 can be effectively relieved.

Like the plurality of holes 31, the plurality of slits 33 penetrate from the surface of the upper electrode 13 to at least the piezoelectric film 11 as shown in FIGS. 3A to 3C. Therefore, the plurality of slits 33 may penetrate from the surface of the upper electrode 13 to the piezoelectric film 11 , or may penetrate from the surface of the upper electrode 13 to the lower electrode 15 . Furthermore, the plurality of slits 33 may penetrate from the surface of the upper electrode 13 to the diaphragm 21 .

In the transducer 1 configured as described above, when drive voltages are applied to the upper electrode 13 and the lower electrode 15 respectively, a potential difference is generated between the upper electrode 13 and the lower electrode 15 . Due to this potential difference, the piezoelectric film 11 contracts and the vibrating film 21 is displaced.

Further, by repeatedly applying the drive voltage to the upper electrode 13 and the lower electrode 15, the vibrating film 21 alternately repeats upward displacement and downward displacement. The vibration of the vibrating membrane 21 causes the air around the vibrating membrane 21 to vibrate, and the vibration of the air is output as sound waves.

[Effect of the first embodiment]
As described above in detail, in the transducer 1 according to this embodiment, a plurality of holes 31 or slits 33 penetrating from the surface of the upper electrode 13 to at least the piezoelectric film 11 are formed. Therefore, since a plurality of holes 31 or slits 33 can be formed in the piezoelectric film 11 that actually contracts, the stress caused by the contraction of the piezoelectric film 11 can be relaxed. As a result, the stress applied to the vibrating membrane 21 can be relaxed, and damage to the vibrating membrane 21 can be prevented.

Moreover, in the transducer 1 according to this embodiment, the plurality of holes 31 or slits 33 penetrate from the surface of the upper electrode 13 to the vibration film 21 . Therefore, since a plurality of holes 31 or slits 33 can be directly formed in the vibrating membrane 21, the stress caused by the contraction of the piezoelectric membrane 11 can be relaxed, and the stress applied to the vibrating membrane 21 can also be directly relaxed. As a result, damage to the vibrating membrane 21 can be prevented more effectively.

Furthermore, in the transducer 1 according to this embodiment, a plurality of holes 31 or slits 33 penetrate from the surface of the upper electrode 13 to the lower electrode 15 . Therefore, the stress caused by the contraction of the piezoelectric film 11 can be relaxed, and the stress of the lower electrode 15 can also be relaxed. As a result, the stress applied to the vibrating membrane 21 can be relaxed, and damage to the vibrating membrane 21 can be prevented.

Further, in the transducer 1 according to this embodiment, when the vibrating membrane 21 is circular, the plurality of holes 31 are arranged point-symmetrically with respect to the center of the vibrating membrane 21 . Therefore, since the plurality of holes 31 can be linearly arranged from the center of the vibrating membrane 21 toward the outer periphery, the stress acting between the center and the outer periphery of the vibrating membrane 21 can be effectively relieved.

Furthermore, in the transducer 1 according to this embodiment, when the vibrating membrane 21 is circular, the plurality of holes 31 are arranged concentrically with respect to the center of the vibrating membrane 21 . Therefore, since the plurality of holes 31 can be linearly arranged from the center of the vibrating membrane 21 toward the outer periphery, the stress acting between the center and the outer periphery of the vibrating membrane 21 can be effectively relieved.

Further, in the transducer 1 according to this embodiment, when the vibrating membrane 21 is circular, the plurality of slits 33 are radially arranged from the center of the vibrating membrane 21 . Therefore, since the slit 33 can be arranged from the center of the vibrating membrane 21 toward the outer peripheral part, the stress acting between the center and the outer peripheral part of the vibrating membrane 21 can be effectively relieved.

[Second embodiment]
Next, a transducer 1 according to a second embodiment will be described with reference to FIGS. 6 and 7. FIG. The transducer 1 according to this embodiment differs from that of the first embodiment in that it is composed of a cantilever type vibrating membrane. Hereinafter, descriptions of contents that overlap with the first embodiment will be omitted, and differences will be mainly described below.

In this embodiment, the membrane body 5 is composed of a cantilever-type vibrating membrane 21 and a membrane supporting portion 23 . The vibrating membrane 21 has a substantially rectangular shape when viewed on a plane parallel to the vibrating membrane 21 . The membrane supporting portion 23 surrounds the vibrating membrane 21 and is connected to one side of the vibrating membrane 21 . A gap 27 is formed between the remaining three sides of the vibrating membrane 21 and the membrane supporting portion 23 . That is, the vibrating membrane 21 is supported in a cantilever shape.

The piezoelectric element 3 is laminated on the upper surface of the vibrating membrane 21 and has a shape corresponding to the shape of the vibrating membrane 21, and has a square shape in the examples shown in FIGS. An electrode pad 13a, which is a circuit pattern for applying a drive voltage to the upper electrode 13, and an electrode pad 15a, which is a circuit pattern for applying a drive voltage to the lower electrode 15, are not provided on the free end side. , is arranged on the proximal end side connected to the membrane support portion 23 .

Here, a plurality of holes 31 are formed in the transducer 1 as shown in FIG. The plurality of holes 31 penetrate from the surface of the upper electrode 13 to the piezoelectric film 11 as shown in FIG. 3B and 3C, the plurality of holes 31 may penetrate from the surface of the upper electrode 13 to the lower electrode 15, or may penetrate from the surface of the upper electrode 13 to the diaphragm 21. good too. Therefore, the plurality of holes 31 penetrate from the surface of the upper electrode 13 to at least the piezoelectric film 11 .

As shown in FIGS. 6 and 7, the plurality of holes 31 are arranged in a plurality of rows in a direction intersecting with the side 40 connected to the membrane supporting portion 23 among the four sides of the square vibration membrane 21 . there is However, as shown in FIG. 6, the plurality of holes 31 are preferably arranged in a plurality of rows perpendicular to the side 40 connected to the membrane supporting portion 23, and are arranged at regular intervals within the rows. preferably.

In the vibrating membrane 21, the side 40 connected to the membrane supporting portion 23 is fixed, and the opposing side 42 is a free end that is displaced. Therefore, the stress applied to the vibrating membrane 21 acts between the side 40 connected to the membrane supporting portion 23 and the opposite side 42 . Therefore, by arranging the plurality of holes 31 in a direction intersecting the side 40 connected to the membrane supporting portion 23, the stress applied to the vibrating membrane 21 can be effectively relieved. At this time, by arranging the plurality of holes 31 in a plurality of rows perpendicular to the side 40 connected to the membrane support portion 23 and arranging them at regular intervals within the rows, the stress applied to the vibrating membrane 21 can be effectively reduced. can be effectively mitigated.

Also, as shown in FIG. 8 , a plurality of slits 33 may be formed instead of the plurality of holes 31 . In this case, the plurality of slits 33 are arranged in a direction intersecting the sides of the vibrating membrane 21 connected to the membrane supporting portion 23 . However, the plurality of slits 33 are preferably arranged perpendicular to the side 40 connected to the membrane supporting portion 23 as shown in FIG.

The stress applied to the vibrating membrane 21 acts between the side 40 connected to the membrane supporting portion 23 and the opposite side 42 . Therefore, by arranging the plurality of slits 33 in a direction intersecting the side 40 connected to the membrane supporting portion 23, the stress applied to the vibrating membrane 21 can be effectively relieved. At this time, by arranging the plurality of slits 33 perpendicularly to the side 40 connected to the membrane supporting portion 23, the stress applied to the vibrating membrane 21 can be effectively relieved.

Moreover, as shown in FIG. 9, each of the plurality of slits 33 may be divided into a plurality of rows. For example, in FIG. 9 , a plurality of slits 33 are arranged in a plurality of rows in a direction intersecting the side 40 connected to the membrane supporting portion 23 . Even if a plurality of slits 33 are arranged in a plurality of rows in this manner, the stress applied to the vibrating membrane 21 can be effectively relieved.

Although the transducer 1 according to the present embodiment has been described as being composed of a cantilever type vibrating membrane, it may be composed of a multi-support type vibrating membrane as shown in FIGS.

As shown in FIGS. 10 and 11, the membrane body 5 is composed of a multi-support vibrating membrane 21 and a membrane support portion 23 . The vibrating membrane 21 has a substantially rectangular shape when viewed on a plane parallel to the vibrating membrane 21 . The membrane supporting portion 23 surrounds the vibrating membrane 21 and is connected to two sides of the vibrating membrane 21 . A gap 27 is formed between the remaining two sides of the vibrating membrane 21 and the membrane supporting portion 23 . That is, the vibrating membrane 21 is supported in a double-supported beam shape. 10 shows the case where a plurality of holes 31 are formed, it is also possible to form a plurality of slits 33 instead of the plurality of holes 31 as shown in FIGS. be. Other configurations are the same as in the case where the vibrating membrane 21 is of the cantilever type, so detailed description thereof will be omitted.

In the transducer 1 according to the present embodiment described above with reference to FIGS. 6 to 11, when drive voltages are applied to the upper electrode 13 and the lower electrode 15 respectively, a potential difference is generated between the upper electrode 13 and the lower electrode 15 . This potential difference causes the piezoelectric film 11 to contract, displacing the free end side of the vibrating film 21 in the film thickness direction in the case of the cantilever type, and displacing the center of the vibrating film 21 in the film thickness direction in the case of the multi-support type. do.

Furthermore, by repeatedly applying the drive voltage to the upper electrode 13 and the lower electrode 15, the vibrating film 21 alternately repeats upward displacement and downward displacement. The vibration of the vibrating membrane 21 causes the air around the vibrating membrane 21 to vibrate, and the vibration of the air is output as sound waves.

[Effect of Second Embodiment]
As described above in detail, in the transducer 1 according to the present embodiment, when the vibrating membrane 21 is square, the plurality of holes 31 are formed with respect to the side 40 of the vibrating membrane 21 connected to the membrane supporting portion 23 . Arrange in multiple columns in a crosswise direction. Therefore, the stress acting between the side 40 connected to the membrane supporting portion 23 and the opposite side 42 can be effectively relieved.

Further, in the transducer 1 according to the present embodiment, when the vibrating membrane 21 has a square shape, the plurality of slits 33 are arranged in a direction intersecting the side 40 of the vibrating membrane 21 connected to the membrane supporting portion 23. . Therefore, the stress acting between the side 40 connected to the membrane supporting portion 23 and the opposite side 42 can be effectively relieved.

[Modification]
Modifications applicable to each of the above-described embodiments will be described below. The modifications shown below are applicable to both the first and second embodiments unless otherwise specified.

(First modification)
In the transducer 1 according to the first modified example, resin is embedded inside the plurality of holes 31 or slits 33 . In the transducer 1, the vibration of the vibrating membrane 21 causes the air around the vibrating membrane 21 to vibrate, and the vibration of the air is output as sound waves. Therefore, if the vibrating membrane 21 is formed with the holes 31 or the slits 33, the air passes through, and the pressure that vibrates the air decreases, resulting in a decrease in the sound wave output.

Therefore, in the transducer 1 according to the first modified example, resin is embedded inside the hole 31 or the slit 33 . Therefore, it is possible to prevent air from passing through the hole 31 or the slit 33, thereby preventing a decrease in sound wave output. The resin may be made of a soft material that expands and contracts according to the displacement of the vibrating membrane 21 .

(Second modification)
In the transducer 1 according to the second modified example, the diameters of the plurality of holes 31 are formed to be smaller than the thickness of the vibrating membrane 21 . In the transducer 1, the vibration of the vibrating membrane 21 causes the air around the vibrating membrane 21 to vibrate, and the vibration of the air is output as sound waves. Therefore, if the vibrating membrane 21 is formed with the holes 31, the air will pass through, and the pressure that vibrates the air will decrease, resulting in a decrease in the sound wave output. However, if the size of the hole 31 is sufficiently small, it is possible to suppress passage of air, thereby preventing a decrease in sound wave output.

Therefore, in the transducer 1 according to the second modified example, the diameter of the hole 31 is made smaller than the thickness of the vibrating membrane 21 . Therefore, it is possible to prevent air from passing through the holes 31, thereby preventing a decrease in sound wave output.

(Third modification)
In the transducer 1 according to the third modification, the total area of the multiple holes 31 or slits 33 is formed to be larger than 10% of the area of the vibrating membrane 21 . Even if the vibrating membrane 21 is formed with the holes 31 or the slits 33, the stress applied to the vibrating membrane 21 cannot be sufficiently reduced if the total area thereof is small.

Therefore, in the transducer 1 according to the third modified example, the total area of the plurality of holes 31 or slits 33 is made larger than 10% of the area of the vibrating membrane 21 . Therefore, a sufficient area of the hole 31 or the slit 33 can be secured to relieve the stress, so that the stress applied to the vibrating membrane 21 can be sufficiently reduced.

Although the first to third modifications have been described in this way, the first to third modifications can also be used in combination with the technical features shown in the respective modifications. Furthermore, the first and second embodiments can be used in combination with the technical features shown in the first to third modifications.

While embodiments of the present invention have been described above, the discussion and drawings forming part of this disclosure should not be construed as limiting the invention. Various alternative embodiments, implementations and operational techniques will become apparent to those skilled in the art from this disclosure.

For example, the transducer may be applied to receive sound waves as well as to transmit sound waves. Moreover, the transducer may be applied to applications for transmitting or receiving not only sound waves but also ultrasonic waves.

REFERENCE SIGNS LIST 1 transducer 3 piezoelectric element 5 film body 11 piezoelectric film 13 upper electrode 13a, 15a electrode pad 15 lower electrode 21 vibration film 23 film supporting portion 25 cavity 27 gap 31 hole 33 slit

Claims (11)

a piezoelectric element comprising a piezoelectric film, an upper electrode laminated on the upper surface of the piezoelectric film, and a lower electrode laminated on the lower surface of the piezoelectric film;
a vibrating membrane supported by a membrane supporting part having a hollow part formed therein;
The piezoelectric element is laminated on the upper surface of the vibration film,
A transducer in which a plurality of holes or slits penetrating from the surface of the upper electrode to at least the piezoelectric film are formed. 2. The transducer according to claim 1, wherein said plurality of holes or slits penetrate from the surface of said upper electrode to said vibrating membrane. 2. The transducer of claim 1, wherein said plurality of holes or slits penetrate from the surface of said upper electrode to said lower electrode. The transducer according to any one of claims 1 to 3, wherein the plurality of holes are arranged point-symmetrically with respect to the center of the vibrating membrane when the vibrating membrane has a circular shape. The transducer according to any one of claims 1 to 3, wherein the plurality of holes are arranged concentrically with respect to the center of the vibrating membrane when the vibrating membrane has a circular shape. 4. The transducer according to any one of claims 1 to 3, wherein the plurality of slits are radially arranged from the center of the vibrating membrane when the vibrating membrane has a circular shape. 4. The plurality of holes according to any one of claims 1 to 3, wherein when the vibrating membrane has a square shape, the plurality of holes are arranged in a plurality of rows in a direction intersecting the side of the vibrating membrane connected to the membrane supporting portion. or the transducer according to claim 1. The plurality of slits according to any one of claims 1 to 3, wherein the plurality of slits are arranged in a direction that intersects a side of the vibrating membrane connected to the membrane supporting portion when the vibrating membrane has a square shape. Transducer as described. The transducer according to any one of claims 1 to 8, wherein resin is embedded inside the plurality of holes or slits. The transducer according to any one of claims 1 to 9, wherein the diameter of said plurality of holes is smaller than the thickness of said vibrating membrane. A transducer according to any one of claims 1 to 10, wherein the total area of said plurality of holes or slits is greater than 10% of the area of said vibrating membrane.

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