A piezoelectric micromechanical ultrasonic transducer and electronic device
By introducing energy interconnection components between the cantilever arms, the problem of inconsistent cantilever cluster structures was solved, the resonant energy of the cantilever cluster was concentrated, and the performance and bandwidth of the piezoelectric micromechanical ultrasonic transducer were enhanced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-16
- Publication Date
- 2026-04-03
AI Technical Summary
The existing piezoelectric micromechanical ultrasonic transducer cantilever clusters suffer from inconsistencies in the structure of each part due to manufacturing uncertainties, resulting in multiple independent resonances that cannot work together to achieve better results.
Energy interconnection components are introduced between the cantilever arms, and the cantilever arms are physically connected through various connection methods to form a resonant weak coupling, so that the cantilever cluster can exchange energy under the resonance peak, thereby enhancing the resonant energy concentration effect of the cantilever arms.
This method achieves energy concentration at each resonant point of the cantilever, increases the intra-band acoustic pressure of the piezoelectric micromechanical ultrasonic transducer, enhances its performance, and maintains multiple resonant peaks without affecting residual stress release.
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Figure CN117920557B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a piezoelectric micromechanical ultrasonic transducer, and more specifically, to a piezoelectric micromechanical ultrasonic transducer with an energy exchange structure. Background Technology
[0002] A piezoelectric micromachined ultrasonic transducer (PMUT) is a type of MEMS device that uses the direct and inverse piezoelectric effects of piezoelectric materials to vibrate a piezoelectric thin film, thereby emitting or receiving ultrasonic signals. The emission and reception of ultrasonic waves are achieved through the bending vibration of the diaphragm. When a PMUT is used to emit ultrasonic waves, it acts as an actuator; when it is used to receive ultrasonic waves, it acts as a sensor. Piezoelectric micromachined ultrasonic transducers, combined with micromechanical processes, offer advantages such as small size and low power consumption, and have broad application prospects in fields such as medical imaging and intelligent sensing.
[0003] Typically, a PMUT (Piezoelectric Micromechanical Ultrasonic Transducer) has a stacked structure of a piezoelectric layer and upper and lower electrodes. Its working principle involves applying an electric field between the upper and lower electrodes, causing lateral internal stress in the piezoelectric layer, which in turn drives the device to bend and vibrate. A PMUT is a type of MUT that uses a piezoelectric layer for electromechanical conversion.
[0004] An existing ultrasonic transducer is constructed by splitting the diaphragm into several identical cantilever clusters, such as... Figure 1 As shown, the solid line represents the ideal structure, and the dashed line represents the actual fabricated structure, which will have multiple resonant points. Since there is no mechanical coupling between the various parts, each part will vibrate independently. Due to uncertainties in the manufacturing process, the inconsistency in the structure of the cantilever cluster leads to multiple resonances. However, these multiple resonances are often independent of each other and cannot cooperate to achieve better results.
[0005] Therefore, the existing technology has problems and needs further improvement and development. Summary of the Invention
[0006] (I) Purpose of the invention: In order to solve the problems existing in the prior art, the purpose of the present invention is to provide a piezoelectric micromechanical ultrasonic transducer with a weak resonant coupling relationship between the cantilever arms of the diaphragm.
[0007] (II) Technical Solution: To solve the above-mentioned technical problems, this technical solution provides a piezoelectric micromechanical ultrasonic transducer, which includes, from top to bottom: an electrode, a piezoelectric layer and a substrate. The electrode and the piezoelectric layer are connected to the substrate with a cavity as a diaphragm. The diaphragm is divided into multiple cantilever arms, which form a cantilever cluster. An energy interconnection component is added between the multiple cantilever arms. The energy interconnection component physically connects the multiple cantilever arms and generates resonant weak coupling, so that the multiple cantilever arms of the piezoelectric micromechanical ultrasonic transducer each have a resonant peak.
[0008] The piezoelectric micromechanical ultrasonic transducer is wherein the energy of one of the cantilever arms at its resonant peak is the sum of the resonant energies of the cantilever cluster without energy interconnection components.
[0009] The piezoelectric micromechanical ultrasonic transducer is wherein, at a certain resonance peak, the energy of the resonance of one of the cantilever arms is the sum of the energies of the cantilever cluster.
[0010] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the surface of the energy exchange component is parallel to the surface of the diaphragm.
[0011] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the energy interconnection component is an arc-shaped connecting arc, which sequentially connects the cantilever arms.
[0012] The piezoelectric micromechanical ultrasonic transducer includes an energy communication component comprising a first connecting line that intersects in a cross shape, and vertical connecting lines at both ends of the first connecting line. The vertical connecting line and the first connecting line form a T-shape, and the vertical connecting line connects adjacent cantilever arms.
[0013] The piezoelectric micromechanical ultrasonic transducer includes an energy interconnection component comprising a U-shaped connecting line for physically connecting adjacent cantilever arms.
[0014] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the surface of the energy exchange component is embedded within the surface of the diaphragm.
[0015] The piezoelectric micromechanical ultrasonic transducer includes a hollowed-out area between adjacent cantilever arms, with an energy communication component embedded within the hollowed-out area.
[0016] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the energy interconnection component is an S-shaped connecting line, which connects adjacent cantilever arms.
[0017] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the energy communication component is a spring-shaped connecting wire, which connects adjacent cantilever arms.
[0018] In the aforementioned piezoelectric micromechanical ultrasonic transducer, an arc-shaped connecting line is provided within the hollowed-out area, and the arc-shaped connecting line connects adjacent cantilever arms through a second connecting line that intersects in a cross shape.
[0019] The piezoelectric micromechanical ultrasonic transducer includes a hollowed-out area comprising a connecting groove between adjacent cantilever arms and two opposing L-shaped connecting grooves at both ends of the connecting groove; a third connecting line with the same shape as the connecting groove is provided in the connecting groove, the third connecting line comprising a parallel line parallel to the adjacent cantilever arms and two L-shaped connecting lines connecting to both ends of the parallel line, the L-shaped connecting lines having opposite opening directions.
[0020] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the hollowed-out area is square, circular, triangular, or rectangular.
[0021] In the aforementioned piezoelectric micromechanical ultrasonic transducer, a waveform connecting line embedded in the diaphragm is provided between adjacent cantilever arms.
[0022] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the waveform connecting line is a signal waveform connecting line, and the number of the signal waveform connecting lines is one or more.
[0023] In the aforementioned piezoelectric micromechanical ultrasonic transducer, when there are multiple signal waveform connection lines, the length of the outer waveform is greater than the length of the inner waveform.
[0024] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the air gap surrounding the energy interconnection component maintains the same morphology as the energy interconnection component.
[0025] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the distance d from the edge of the air gap to the cavity is not greater than one-tenth of the cavity diameter d1.
[0026] The piezoelectric micromechanical ultrasonic transducer, wherein the energy communication component does not contain electrodes.
[0027] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the energy communication component includes electrodes, and the energy communication component needs to be isolated from the driving electrodes of the piezoelectric micromechanical ultrasonic transducer.
[0028] In the aforementioned piezoelectric micromechanical ultrasonic transducer, the diaphragm is square, and along the diagonal of the square, the diaphragm is divided into four triangular cantilever arms, which together form a cantilever cluster.
[0029] An electronic device includes: a processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other through the communication bus, and the processor is connected to the piezoelectric micromechanical ultrasonic transducer described in any of the above embodiments.
[0030] (III) Beneficial Effects: The piezoelectric micromechanical ultrasonic transducer and electronic device provided by this invention introduces energy interconnection components between the cantilever arms, which can achieve an energy concentration effect, thereby enhancing the displacement of the cantilever arms at various resonant points in the piezoelectric micromechanical ultrasonic transducer (PMUT), thus increasing the sound pressure within the entire bandwidth of the PMUT. Furthermore, the energy interconnection components result in extremely weak coupling, which does not affect the release of residual stress. Simultaneously, the PMUT still possesses multiple resonant peaks, serving only to transfer energy, while the overall structure of the cantilever cluster remains unchanged. Attached Figure Description
[0031] Figure 1 This is a top view of a piezoelectric micromechanical ultrasonic transducer under existing technology;
[0032] Figure 2 This is a longitudinal cross-sectional view of a piezoelectric micromechanical ultrasonic transducer under existing technology;
[0033] Figure 3 This is a schematic diagram of the structure of the energy interconnection component of the piezoelectric micromechanical ultrasonic transducer of the present invention, which consists of four arc-shaped connecting arcs;
[0034] Figure 4 This is a schematic diagram of the energy interconnection component of the piezoelectric micromechanical ultrasonic transducer of the present invention, which includes two first connecting lines and a vertical connecting line that intersect in a cross shape.
[0035] Figure 5 This is a schematic diagram of the energy interconnection component of the piezoelectric micromechanical ultrasonic transducer of the present invention, which includes four Z-shaped connecting lines;
[0036] Figure 6 This is a schematic diagram of the energy concentration effect of a single cantilever in the piezoelectric micromechanical ultrasonic transducer of the present invention;
[0037] Figure 7 This is a schematic diagram of the first preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy communication component is embedded inside the diaphragm;
[0038] Figure 8 This is a schematic diagram of a second preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy communication component is embedded inside the diaphragm.
[0039] Figure 9 This is a schematic diagram of the third preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy communication component is embedded inside the diaphragm.
[0040] Figure 10This is a schematic diagram of the fourth preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy communication component is embedded inside the diaphragm;
[0041] Figure 11 This is a schematic diagram of the fifth preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy interconnection component is embedded inside the diaphragm;
[0042] Figure 11-1 This is a schematic diagram of the longitudinal cross-sectional structure of the fifth preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy interconnection component is embedded inside the diaphragm and does not contain electrodes.
[0043] Figure 11-2 This is a schematic diagram of the longitudinal cross-sectional structure of the fifth preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, in which the energy interconnection component is embedded inside the diaphragm, including electrodes.
[0044] Figure 12 This is a performance comparison diagram of the piezoelectric micromechanical ultrasonic transducer (PMUT) with energy interconnection components and the piezoelectric micromechanical ultrasonic transducer (PMUT) with a strong coupling structure.
[0045] Figure 13 This is a schematic diagram of the structure of an electronic device with a piezoelectric micromechanical ultrasonic transducer according to the present invention. Detailed Implementation
[0046] The present invention will be further described in detail below with reference to preferred embodiments. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.
[0047] The accompanying drawings are schematic diagrams of embodiments of the present invention. It should be noted that these drawings are for illustrative purposes only and are not drawn to scale, and should not be construed as limiting the actual scope of protection of the present invention.
[0048] This invention provides a piezoelectric micromechanical ultrasonic transducer, such as... Figure 1 and Figure 2 As shown, from top to bottom, it includes: an electrode 1, a piezoelectric layer 2, and a substrate 3. The electrode 1 includes a top electrode and a bottom electrode connected to the substrate, and the piezoelectric layer 2 is located between the top electrode and the bottom electrode. The electrode 1 and the piezoelectric layer 2 are connected as a diaphragm above the substrate 3, which has a cavity. The diaphragm is divided into multiple cantilever arms, which form a cantilever cluster.
[0049] The present invention adds an energy interconnection component between multiple cantilever arms, which can physically connect the multiple cantilever arms and generate resonant weak coupling; such that at a certain resonance peak, multiple cantilever arms of the piezoelectric micromechanical ultrasonic transducer each have a resonance peak, and the resonance energy of one cantilever arm is the sum of the energy of the cantilever cluster, rather than just the resonance energy generated by a single cantilever arm, thereby enhancing the performance of the piezoelectric micromechanical ultrasonic transducer.
[0050] In a first preferred embodiment of the piezoelectric micromechanical ultrasonic transducer of the present invention, the diaphragm is square, as shown below. Figure 1 As shown, along the diagonal of the square, the diaphragm is divided into four triangular cantilever arms, which form a cantilever cluster. Figure 1 The solid line represents the ideal design structure, while the dashed line represents the actual fabricated structure. During the micromachining of the cantilever cluster, machining errors can lead to inconsistencies among the four cantilever structures, resulting in multiple resonant points in the actual fabricated structure. This causes the four cantilevers to vibrate independently with inconsistent resonant frequencies, severely impairing the performance of the piezoelectric micromechanical ultrasonic transducer.
[0051] The following embodiments of the present invention are described in detail with a square diaphragm. The diaphragm can be circular or other shapes, and the present invention does not limit it.
[0052] The energy interconnection component of the present invention physically connects multiple cantilever arms and generates resonant weak coupling, so that multiple cantilever arms of the piezoelectric micromechanical ultrasonic transducer each have a resonant peak, and the energy of one cantilever arm at its resonant peak is the sum of the resonant energies of the cantilever cluster when there is no energy interconnection component.
[0053] The diaphragm of this invention is square, comprising a piezoelectric micromechanical ultrasonic transducer with four triangular cantilever clusters. A first preferred embodiment is shown below. Figure 3 As shown, the energy interconnection component consists of four arc-shaped connecting arcs 401. These arc-shaped connecting arcs 401 can sequentially connect four triangular cantilever arms to achieve physical connectivity and generate resonant weak coupling. When the piezoelectric micromechanical ultrasonic transducer is square, the four arc-shaped connecting arcs 401 are axially symmetrical. The four arc-shaped connecting arcs 401 of this invention can be etched onto the same diaphragm using an etching process, along with the cantilever cluster. The energy interconnection component of this invention, when the piezoelectric micromechanical ultrasonic transducer is in resonance, only serves to transfer energy without affecting other original characteristics of the piezoelectric micromechanical ultrasonic transducer (PMUT). Figure 6 As shown, Figure 3 After the cantilever clusters in the middle are equipped with energy interconnection components, Figure 3 The four cantilever arms still produce maximum displacement at their respective resonant frequency points, but their maximum displacement is four times that of the four cantilever arms.
[0054] The diaphragm of this invention is square, comprising a piezoelectric micromechanical ultrasonic transducer with four triangular cantilever clusters. A second preferred embodiment is as follows: Figure 4 As shown, the energy interconnection component includes two first connecting lines 402 that intersect in a cross shape, and a vertical connecting line 403 at both ends of the first connecting lines. The vertical connecting line 403 and the first connecting lines 402 form a T-shape, and the vertical connecting line 403 connects two adjacent cantilever arms. The energy interconnection component is located in the gap between the cantilever arms.
[0055] The diaphragm of this invention is square, comprising a piezoelectric micromechanical ultrasonic transducer with four triangular cantilever clusters. A third preferred embodiment is as follows: Figure 5 As shown, the energy interconnection component includes four Z-shaped connecting lines 404, which are used to physically connect two adjacent triangular cantilever arms, so that the cantilever cluster generates resonant weak coupling.
[0056] This invention Figures 3-5 The surface of the energy interconnection component is parallel to the surface of the diaphragm.
[0057] The piezoelectric micromechanical ultrasonic transducer of this invention introduces energy interconnection components between the cantilever arms, achieving an energy concentration effect. This enhances the displacement of the cantilever arms at various resonant points within the PMUT, thereby increasing the sound pressure level across the entire PMUT bandwidth. Furthermore, the energy interconnection components result in extremely weak coupling, not affecting residual stress release. Simultaneously, the PMUT still exhibits multiple resonant peaks, serving only as an energy transfer element within the overall cantilever cluster structure. Each cantilever segment still vibrates independently, but the displacement of each segment is several times greater than before. This is due to the energy interconnection structure concentrating energy from other segments into that segment, such as... Figure 6 The diagram illustrates the energy concentration effect of a single cantilever. When an energy interconnection component is included, the displacement of the cantilever under resonance is four times that without the energy interconnection component, meaning that the design transfers the energy of the other three cantilever arms to this single cantilever arm.
[0058] The piezoelectric micromechanical ultrasonic transducer of the present invention includes four triangular cantilever clusters. The energy interconnection structure between the cantilever clusters can also be embedded inside the diaphragm. Through the longer length and more folded structure, weaker coupling is achieved, thereby better realizing the energy concentration effect.
[0059] This invention Figures 7-10 The energy interconnection component is embedded inside the diaphragm surface.
[0060] In the first preferred embodiment of the piezoelectric micromechanical ultrasonic transducer described in this invention, the energy communication component is embedded inside the diaphragm, such as... Figure 7 As shown, a hollow area can be set between adjacent cantilever arms, and an energy interconnection component can be embedded within the hollow area. The hollow area described in this invention can be various shapes such as square, rectangle, circle, and triangle, and this invention is not limited thereto.
[0061] The hollowed-out area is square, and the energy interconnection component is an S-shaped connecting line 501, which connects adjacent cantilever arms. The energy interconnection component of the piezoelectric micromechanical ultrasonic transducer may include four hollowed-out areas, each with a direction, and each directional hollowed-out area is provided with an S-shaped connecting line 501 connecting to an adjacent cantilever arm. The hollowed-out areas, S-shaped connecting lines 501, and cantilever arms in the energy interconnection component are simultaneously etched onto the diaphragm. The S-shaped connecting lines 501 and cantilever arms in the energy interconnection component of this invention can also be manufactured using different processes; the S-shaped connecting lines 501 are manufactured using other processes and then placed on the cantilever arms, and there are no specific limitations.
[0062] The energy communication component of the piezoelectric micromechanical ultrasonic transducer described in this invention is, in a second preferred embodiment, embedded within the diaphragm, such as... Figure 8 As shown, a hollow area can be set between adjacent cantilever arms, and an energy interconnection component can be embedded within the hollow area. The hollow area is rectangular, and the energy interconnection component is a spring-shaped connecting line 502, which connects adjacent cantilever arms. The energy interconnection component and the cantilever arms are simultaneously etched onto the diaphragm. This invention does not limit the shape of the hollow area. The spring-shaped connecting line 502 can achieve a longer and more flexible energy interconnection structure, thereby achieving weaker coupling.
[0063] The energy communication component of the piezoelectric micromechanical ultrasonic transducer of the present invention is embedded inside the diaphragm in a third preferred embodiment, such as... Figure 9 As shown, a hollow area can be set between adjacent cantilever arms. The hollow area is triangular, and an arc-shaped connecting line 503 is set within the triangular hollow area. The arc-shaped connecting line connects the diagonal cantilever arms and adjacent cantilever arms through a cross-shaped second connecting line 504. The energy interconnection component includes the cross-shaped second connecting line 504 and the arc-shaped connecting lines 503 at both ends of the second connecting line. The arc-shaped connecting lines 503 are located within the triangular hollow area. The energy interconnection component is located in the gap between the cantilever arms, and the hollow area is also located in the gap between the cantilever arms.
[0064] The energy communication component of the piezoelectric micromechanical ultrasonic transducer of the present invention is embedded inside the diaphragm in a fourth preferred embodiment, such as... Figure 10 As shown, a hollow area can be set between adjacent cantilever arms. The hollow area includes a connecting groove between adjacent cantilever arms, and two reverse L-shaped connecting grooves at both ends of the connecting groove, generally forming a 2-shaped structure, specifically as shown below. Figure 10As shown. A third connecting line 505, identical in shape to the connecting trench, is provided within the trench. The third connecting line includes a parallel line parallel to the adjacent cantilever and two L-shaped connecting lines 506 connecting the two ends of the parallel line. The L-shaped connecting lines have opposite opening directions. The energy interconnection component includes the third connecting line, and both the energy interconnection component and the cantilever are simultaneously etched onto the diaphragm.
[0065] The diaphragm of the piezoelectric micromechanical ultrasonic transducer of the present invention can also be circular, equilateral hexagonal, or other shapes, and multiple cantilever arms are formed according to symmetry, forming a cantilever cluster. The shape of the diaphragm is not limited in the present invention.
[0066] The energy communication component of the piezoelectric micromechanical ultrasonic transducer of the present invention is embedded inside the diaphragm in the fifth preferred embodiment, such as... Figure 11 As shown, waveform connecting lines embedded in the diaphragm can be provided between adjacent cantilever arms. These waveform connecting lines are signal waveform connecting lines 507. The number of signal waveform connecting lines 507 in this invention can be one or more. A preferred embodiment of this invention uses two signal waveform connecting lines, but this is not a limitation. When there are multiple signal waveform connecting lines, the outer waveform length is greater than the inner waveform length.
[0067] To avoid acoustic short circuits, this invention minimizes the air gap around the energy interconnection structure, thus ensuring that the air gap around the energy interconnection component is essentially consistent with the shape of the energy interconnection component. Figure 11-1 And 11-2 showed Figure 11 The longitudinal cross-sectional view is shown. The energy interconnection component of this invention may not contain an electrode portion, such as... Figure 11-1 As shown.
[0068] To enhance the stability of the energy exchange component, the piezoelectric micromechanical ultrasonic transducer of this invention can be equipped with an electrode portion. However, it is necessary to avoid applying piezoelectric driving force. Therefore, the energy exchange component needs to be isolated from the driving electrode of the piezoelectric micromechanical ultrasonic transducer, such as... Figure 11-2 As shown.
[0069] The piezoelectric micromechanical ultrasonic transducer of the present invention, such as Figure 11 As shown, the cavity size d1 is generally larger than the back-engraved size d2. Therefore, the air here is compressed, resulting in additional losses. The air gap around the energy interconnection component can serve as an effective way to release the damping of the compression membrane. In particular, the distance d from the edge of the air gap to the cavity is no greater than one-tenth of the cavity diameter d1.
[0070] Figure 12This paper demonstrates the performance differences between the piezoelectric micromechanical ultrasonic transducer (PMUT) with an energy-interchange component and the piezoelectric micromechanical ultrasonic transducer (PMUT) with a strongly coupled structure. The solid line represents a typical phase diagram in vacuum of the frequency-splitting device proposed in this patent, showing the presence of multiple resonance peaks and a wide bandwidth. The dashed line represents a typical phase diagram in vacuum under strong coupling, showing only one resonance peak and a narrow bandwidth. This also results in excessive residual stress remaining within the structure, thus affecting device performance.
[0071] The present invention also includes an electronic device comprising the technical features of any of the embodiments of the above piezoelectric micromechanical ultrasonic transducer (PMUT), such as... Figure 13 As shown, the electronic social security system may include: a processor 1002, a communications interface 1004, a memory 1006, and a communication bus 1008.
[0072] The processor 1002, communication interface 1004, and memory 1006 communicate with each other via communication bus 1008.
[0073] Communication interface 1004 is used to communicate with other network elements such as clients or other servers.
[0074] The processor 1002 is used to execute program 1010, specifically to execute the relevant steps in the above-described email processing method embodiment.
[0075] Specifically, program 1010 may include program code that includes computer operation instructions.
[0076] The processor 1002 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. The terminal may include one or more processors of the same type, such as one or more CPUs; or it may include processors of different types, such as one or more CPUs and one or more ASICs.
[0077] Memory 1006 is used to store program 1010. Memory 1006 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.
[0078] The piezoelectric micromechanical ultrasonic transducer (PMUT) described herein is a preferred embodiment of any of the piezoelectric micromechanical ultrasonic transducers described in this specification.
[0079] The above description illustrates preferred embodiments of the present invention and helps those skilled in the art to more fully understand the technical solution of the present invention. However, these embodiments are merely illustrative and should not be construed as limiting the specific implementation of the present invention to these embodiments. For those skilled in the art, several simple deductions and modifications can be made without departing from the inventive concept, and all such modifications should be considered within the protection scope of the present invention.
Claims
1. A piezoelectric micromechanical ultrasonic transducer, comprising, from top to bottom: An electrode, a piezoelectric layer, and a substrate, characterized in that the electrode and the piezoelectric layer are connected as a diaphragm to a substrate having a cavity, the diaphragm being divided into a plurality of cantilever arms forming a cantilever cluster; An energy interconnection component is added between the multiple cantilever arms. The energy interconnection component physically connects the multiple cantilever arms and generates resonant weak coupling, so that each of the multiple cantilever arms of the piezoelectric micromechanical ultrasonic transducer has a resonant peak.
2. The piezoelectric micromechanical ultrasonic transducer according to claim 1, characterized in that, This makes the energy of one of the cantilever arms at its resonance peak equal to the sum of the resonance energies of the cantilever cluster when there are no energy interconnection components.
3. The piezoelectric micromechanical ultrasonic transducer according to claim 1, characterized in that, The surface of the energy interconnection component is parallel to the surface of the diaphragm.
4. The piezoelectric micromechanical ultrasonic transducer according to claim 3, characterized in that, The energy interconnection component is an arc-shaped connecting arc, which connects the cantilever in sequence.
5. The piezoelectric micromechanical ultrasonic transducer according to claim 3, characterized in that, The energy interconnection component includes a first connecting line that intersects in a cross shape, and vertical connecting lines at both ends of the first connecting line. One vertical connecting line and the first connecting line form a T-shape, and the vertical connecting line connects adjacent cantilever arms.
6. The piezoelectric micromechanical ultrasonic transducer according to claim 3, characterized in that, The energy interconnection component includes a U-shaped connecting line, which is used to physically connect adjacent cantilever arms.
7. The piezoelectric micromechanical ultrasonic transducer according to claim 1, characterized in that, The energy interconnection component is embedded inside the diaphragm surface.
8. The piezoelectric micromechanical ultrasonic transducer according to claim 7, characterized in that, A hollow area is set between adjacent cantilever arms, and an energy interconnection component is embedded in the hollow area.
9. The piezoelectric micromechanical ultrasonic transducer according to claim 8, characterized in that, The energy interconnection component is an S-shaped connecting line, which connects adjacent cantilever arms.
10. The piezoelectric micromechanical ultrasonic transducer according to claim 8, characterized in that, The energy interconnection component is a spring-shaped connecting line, which connects adjacent cantilever arms.
11. The piezoelectric micromechanical ultrasonic transducer according to claim 8, characterized in that, An arc-shaped connecting line is provided within the hollowed-out area, and the arc-shaped connecting line connects adjacent cantilever arms through a second connecting line that intersects in a cross shape.
12. The piezoelectric micromechanical ultrasonic transducer according to claim 8, characterized in that, The hollowed-out area includes a connecting groove between adjacent cantilever arms and two reverse L-shaped connecting grooves at both ends of the connecting groove; a third connecting line with the same shape as the connecting groove is provided in the connecting groove, the third connecting line includes a parallel line parallel to the adjacent cantilever arms and two L-shaped connecting lines connecting to the two ends of the parallel line, the opening directions of the L-shaped connecting lines being opposite.
13. The piezoelectric micromechanical ultrasonic transducer according to claim 8, characterized in that, The hollowed-out areas can be square, circular, triangular, or rectangular.
14. The piezoelectric micromechanical ultrasonic transducer according to claim 7, characterized in that, A waveform connecting line embedded in the diaphragm is set between adjacent cantilever arms.
15. The piezoelectric micromechanical ultrasonic transducer according to claim 14, characterized in that, The waveform connection line is a signal waveform connection line, and the number of the signal waveform connection lines is one or more.
16. The piezoelectric micromechanical ultrasonic transducer according to claim 15, characterized in that, When there are multiple signal waveform connection lines, the length of the outer waveform is greater than the length of the inner waveform.
17. The piezoelectric micromechanical ultrasonic transducer according to claim 7, characterized in that, The air gap around the energy interconnection component is consistent with the shape of the energy interconnection component.
18. The piezoelectric micromechanical ultrasonic transducer according to claim 17, characterized in that, The distance d from the edge of the air gap to the cavity is no greater than one-tenth of the cavity diameter d1.
19. The piezoelectric micromechanical ultrasonic transducer according to claim 1, characterized in that, The energy interconnection component does not contain electrodes.
20. The piezoelectric micromechanical ultrasonic transducer according to claim 1, characterized in that, The energy interconnection component includes electrodes, and the energy interconnection component needs to be isolated from the drive electrodes of the piezoelectric micromechanical ultrasonic transducer.
21. The piezoelectric micromechanical ultrasonic transducer according to claim 1, characterized in that, The diaphragm is square, and along the diagonal of the square, the diaphragm is divided into four triangular cantilever arms, which together form a cantilever cluster.
22. An electronic device, comprising: The processor, memory, communication interface, and communication bus are provided. The processor, memory, and communication interface communicate with each other through the communication bus. The processor is connected to the piezoelectric micromechanical ultrasonic transducer according to any one of claims 1-21.
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