MEMS component, MEMS speaker, and method for electrically actuating a drive unit of a MEMS component

Abstract

The invention relates to a MEMS component (1) for a MEMS loudspeaker (30), having a carrier structure (2) with a first through-hole (3) leading to a front volume (4) of the MEMS component (1) and a second through-hole (5) leading to a rear volume (6) of the MEMS component (1), displacement elements (7) which are fixed to the carrier structure (2) and are movable relative to one another, a variable volume chamber (8) being configured between each two adjacent displacement elements (7), an electrically actuatable drive unit (9) for generating a movement of the displacement elements (7), at least one displacement element (7) being fixed to a carrier beam (11) of the carrier structure (2) via a carrier membrane (10), the drive unit (9) having at least one piezoelectric drive element (12) which is arranged on the carrier membrane (10) and which, by way of a deformation of the carrier membrane (10), causes a pivoting movement (13) of the displacement element (7) about a pivot axis (14) which extends along the fixing of the displacement element (7) on the carrier membrane (10).

Description

Technical Field

[0001] This invention relates to a MEMS component for a MEMS loudspeaker and a MEMS loudspeaker having such a MEMS component. The invention also relates to a method for electrically controlling a drive unit of such a MEMS component. Background Technology

[0002] MEMS loudspeakers are a known existing technology. The abbreviation MEMS stands for Microelectromechanical Systems, which enables the miniaturization of electromechanical functional components (such as actuators and sensors) through microstructure characteristics and suitable manufacturing processes.

[0003] US 2012 / 0 018 244 A1 relates to a MEMS loudspeaker having a cavity defined by a deformable structure and an actuator for moving or deforming the structure to generate pressure pulses. Summary of the Invention

[0004] According to the present invention, a MEMS component for a MEMS loudspeaker is provided, comprising: a support structure having a first through-hole leading to a front volume of the MEMS component and a second through-hole leading to a rear volume of the MEMS component; displacement elements fixed to the support structure and movable relative to each other, wherein variable volume cavities are respectively constructed between two adjacent displacement elements; and an electrically controllable drive unit for generating movement of the displacement elements. Here, at least one displacement element is fixed to a support beam of the support structure via a support membrane, and the drive unit has at least one piezoelectric drive element disposed on the support membrane, the piezoelectric drive element being configured to cause pivoting movement of the displacement element about a pivot axis by deformation of the support membrane, the pivot axis extending along the fixed point of the displacement element on the support membrane.

[0005] In short, it is recommended to fix the displacement element used to generate sound to the rigid component frame by means of a flexible suspension structure, and use the flexible suspension structure to excite the displacement element to perform rotational deflection motion.

[0006] The MEMS component based on the proposed features has the following advantages: By arranging the piezoelectric driving element on the carrier membrane, the displacement element can be precisely and significantly excited to achieve pivoting motion as rotational deflection. Furthermore, suspending the displacement element on the carrier membrane allows for a larger pivoting angle of the displacement element with the same power consumption, thereby achieving improved performance and higher sound pressure level of the MEMS component. In addition, the MEMS component based on the proposed features has the following advantages: By suspending the displacement element on the carrier membrane, a stable and drop-resistant component design is achieved, allowing the displacement element to be suspended along its entire length, thus obtaining more robust performance against external mechanical influences. Compared to schemes that directly fix the driving element to the displacement element, the proposed MEMS component has the advantage of reduced mechanical stress in the fixed area of ​​the displacement element. Specifically, the fixed area and driving area of ​​the displacement element are spatially separated, and the mechanical stress associated with the excitation of the driving element can be distributed across the entire carrier membrane, rather than concentrated on the displacement element.

[0007] Essentially, a MEMS component can be a device with mechanical and electrical microstructures manufactured using semiconductor technology. Due to its microstructure design, a MEMS component may be suitable for implementation as a system-on-a-chip (SoC). A MEMS component can, for example, be made from one or more substrates, such as a silicon wafer. This MEMS component is intended for use in a MEMS loudspeaker. For this purpose, the MEMS component can be configured to generate sound through air displacement. In other words, pressure pulses within the audible frequency range can be generated using this MEMS component.

[0008] The support structure of the MEMS component can be a component assembly with a primary mechanical function. The support structure may, for example, have side frames and optionally a substrate. Furthermore, it has at least one support beam connected to the side frames and / or the substrate for fixing the support membrane. The support beam here is a mechanical support structure, i.e., a horizontal support member, which extends substantially parallel to the membrane surface of the support membrane and ensures the required mechanical stability within a functional area within the external side frame of the support structure. Optionally, additional vertical reinforcing supports may be provided, extending substantially perpendicular to the membrane surface of the support membrane, and may contribute to improving the mechanical stability of the MEMS component.

[0009] The first and second through-holes of the MEMS component connect the volumetric cavity constructed between corresponding adjacent displacement elements to the front and rear volumes of the MEMS component, wherein the front and rear volumes are located on different sides of the MEMS component. These through-holes serve as inlets and outlets for the volumetric cavity in the sense of air inlets and air outlets, and are used to output the sound pressure generated by the displacement elements. The first and second through-holes can, for example, be constructed between the substrate of the supporting structure and / or two adjacent supporting beams.

[0010] Displacement elements can be constructed, for example, as plates or sheets. They can be suspended substantially vertically on a support membrane and have a predominant extension along the longitudinal direction of the MEMS component. They represent movable partitions and can be moved to increase or decrease the volume cavity constructed between two displacement elements to draw in air and displace it for the generation of a predetermined sound pressure. The volume cavity can be defined laterally by side frames of the support structure. The displacement element can have a fixed end fixed to the support membrane and a free end opposite it that performs pivoting motion. Essentially, the MEMS component can be implemented with at least two displacement elements movable relative to each other, wherein any number of displacement elements arranged side-by-side can be used. The displacement element can pivot about its fixed point on the support membrane, so that the free end can pivot about this fixed area. Deformation of the support membrane is converted into rotation of the displacement element, which can include a predominantly rotational component and a slight translational component. When the displacement element has a large extension between its fixed point and free end, it can be assumed to be a nearly purely rotational deflection motion.

[0011] The supporting membrane can be considered as the flexible, particularly elastically deformable, part of the supporting structure. The supporting membrane can have a lower bending stiffness than the supporting beams or side frames of the supporting structure. For example, the supporting membrane can be made thinner than the adjacent supporting structure to achieve flexible properties. The supporting membrane can be made of silicon, for example. The supporting membrane can extend laterally to the displacement element, thus creating a T-shaped connection between the displacement element and the supporting membrane in cross-section. The supporting membrane mechanically and flexibly connects the rigid part of the supporting structure to the displacement element and can be deformed by a piezoelectrically driven element. Deformation can, for example, accompany the bending of the supporting membrane, particularly wavy bending. According to one configuration possibility, the displacement element can be connected to the supporting structure by a unilateral suspension, wherein the displacement element is held on one side by a supporting beam and a supporting membrane anchored thereto, thus providing a compact implementation.

[0012] The piezoelectric actuation element can be formed from a piezoelectric stack containing a piezoelectric material, particularly a nonlinear material such as PZT (lead zirconate titanate). Layer deformation can be achieved in the stack via an electrical signal, resulting in deformation of the actuation element and the carrier membrane connected thereto, which can be described, for example, as a linear deformation about a deviated rest position. In other words, actuation of the carrier membrane is achieved through the arching of the piezoelectric structure. The piezoelectric actuation element, particularly the piezoelectric active material of the piezoelectric actuation element as an electromechanical transducer structure for deforming the carrier membrane, can be arranged, for example, on the carrier membrane portion between the carrier beam and the displacement element. The main electrical components of the piezoelectric actuation element (e.g., electrodes) can optionally extend beyond the aforementioned carrier membrane portion. The piezoelectric active material of the actuation element can extend on the carrier membrane between the carrier beam and the displacement element, parallel to their main extension directions. Therefore, the piezoelectric active material of the actuation element can be positioned on the flexibly deformable carrier membrane portion between the membrane fixation point of the displacement element and the membrane fixation point of the carrier beam to achieve effective and significant deformation of the carrier membrane, thereby deflecting the displacement element. The drive unit of the MEMS component may have at least one piezoelectric drive element and an electrical wiring structure for controlling the at least one piezoelectric drive element. The electrical wiring structure may be connected to a signal processing unit (such as an ASIC), for example, via wire bonding.

[0013] According to one embodiment, the support membrane can be anchored to two spaced-apart support beams of the support structure, and the displacement element can be arranged between the support beams and fixed to the support membrane. Therefore, the displacement element can be held on both sides by the two support beams and the support membrane extending between the support beams. In this embodiment, the deformable support membrane on both sides of the displacement element provides improved deflectability. Furthermore, the multi-sided connection of the displacement element to the support structure via the support membrane extending on both sides provides greater stability.

[0014] According to one embodiment, at least one piezoelectric driving element can be arranged on the bearing membrane between the spaced-apart bearing beams and the displacement element. This allows for independent, particularly reverse, deformation of the bearing membrane on both sides of the displacement element, thereby achieving improved deflection behavior of the displacement element. The piezoelectric driving elements can be at least layer-by-layer independently operable, for example, connected to different potentials. Therefore, different electrical signals can be applied to the piezoelectric driving elements, for example, to achieve the aforementioned reverse deformation of the bearing membrane.

[0015] According to one embodiment, a first carrier film can be disposed on a first side of the MEMS component, and a second carrier film can be disposed on a second side of the MEMS component opposite to the first side. In short, carrier films can be disposed on different sides of the MEMS component (e.g., upper and lower sides). Accordingly, displacement elements can be connected to the carrier films on different sides, and the free ends performing pivoting movements extend in opposite directions. This provides a compact embodiment and also enables displacement of a larger air volume because the free ends of the displacement elements are not limited in their deflection by oscillating towards each other, but are deflected on different sides of the MEMS component. In this embodiment, piezoelectric actuation elements are also disposed on the respective carrier films on different sides of the MEMS component. For a compact design, it is conceivable that the MEMS component, viewed in the direction of arrangement of the displacement elements, has at least partially an alternating arrangement of upper and lower carrier films. This embodiment can be achieved, for example, by unilateral suspension of the displacement elements on a single carrier beam and / or unilateral suspension of the displacement elements on two carrier beams.

[0016] According to one embodiment, a first carrier membrane can be anchored to a first carrier beam, and a second carrier membrane can be anchored to a second carrier beam. The free ends of displacement elements fixed to the first carrier membrane extend toward the second carrier beam, and the free ends of displacement elements fixed to the second carrier membrane extend toward the first carrier beam. Therefore, the free ends of the displacement elements oscillate near the opposing carrier beams. This configuration allows for the compact and stable design of MEMS components.

[0017] According to one embodiment, the displacement element may have a main extension in the longitudinal direction, wherein a first through-hole and / or a second through-hole has an opening length in the longitudinal direction, which is at least 75% of the main extension of the displacement element. In short, the length of at least one through-hole may be at least almost or exactly the same as the length of the displacement element. This provides a large opening area through which extensive and uniform air intake and pressure pulse output can be achieved. The opening length of the through-hole can be compared in particular to the main extension of the nearest displacement element. The main extension can be considered as the following extension of the displacement element, corresponding to the maximum extension along the spatial axis. The displacement element may have a length extension, a width extension, and a height extension, wherein the length extension is the largest of the aforementioned extensions. According to one configuration possibility, the opening length of the first and / or second through-hole in the longitudinal direction may be at least 85% or at least 95% of the main extension of the displacement element. Here, the opening length refers to the total opening area of ​​the through-holes under consideration between two displacement elements, which may also be interrupted, for example, by structurally stable lateral supports.

[0018] According to one embodiment, the piezoelectric driving element may have an extension in the longitudinal direction, which is at least 75% of the main extension of the displacement element. In short, the length of the piezoelectric driving element may be at least almost or exactly the same as the length of the displacement element. This allows for membrane excitation over almost the entire membrane length, thereby enabling uniform and significant deflection of the displacement element.

[0019] According to one embodiment, the displacement element may have a main extension in the longitudinal direction, wherein the first and / or second vias have an opening length in the longitudinal direction, which is at most 75% of the main extension of the displacement element. In short, at least one via can be significantly shorter than the displacement element. Improved pressure build-up can be achieved in the volumetric cavity due to the limited opening area of ​​the vias in the longitudinal direction. Furthermore, higher packaging density of the displacement element and drive element can be achieved because more area is available on the sides of the vias in the longitudinal direction. Ultimately, higher sound pressure levels can be achieved. The opening length of the vias can be compared, in particular, to the main extension of the nearest displacement element. The first and / or second vias can, for example, be centered relative to the main extension of the displacement element. According to one configuration possibility, the opening length of the first and / or second vias in the longitudinal direction can be at most 65% or at most 55% of the main extension of the displacement element.

[0020] According to one embodiment, the longitudinal extension of the piezoelectric driving element can be interrupted by a first or second through-hole. In this embodiment, efficient area division is achieved, with driving regions and through-hole regions spatially separated from each other, rather than arranged sequentially adjacently, for example, by alternating through-holes and driving elements. Thus, more driving elements can be arranged in the driving regions. The first or second through-hole can, for example, be centrally positioned between two driving regions on the carrier film. With a centrally positioned through-hole, the longitudinal extension of the driving element on the carrier film is reduced, but sufficient carrier film deformation to deflect the displacement element is still achieved.

[0021] According to one embodiment, at least two independently operable piezoelectric drive elements can be arranged on the support membrane on the same side of the displacement element. This allows for better mapping and precise shaping of the predetermined bending curve of the support membrane. Consequently, more precise deformation of the support membrane and improved deflection behavior of the connected displacement element can be obtained. The piezoelectric drive elements can be arranged side-by-side in a region of the support membrane facing the first side of the displacement element. Therefore, this embodiment can be distinguished from other embodiments, but can also be combined with those embodiments in which at least one piezoelectric drive element is arranged on the support membrane on the first and second sides of the displacement element, respectively. The piezoelectric drive elements can be arranged on the support membrane portion between the support beam and the displacement element. The piezoelectric drive elements can be arranged side-by-side in a transverse to longitudinal direction and extend substantially parallel to each other. It is also conceivable to arrange three or more piezoelectric drive elements on the same side of the displacement element (e.g., on the same support membrane portion) to achieve more precise membrane deformation. To optimize the deformation behavior of the support membrane, the piezoelectric drive elements can also have different dimensions, such as different widths in a transverse view. Piezoelectric drive elements can have layer units in a piezoelectric layer structure that are spaced apart from each other, so that they can be manipulated independently.

[0022] According to one embodiment, the driving unit may have at least two piezoelectric driving elements formed by a layer structure having a first potential layer and a second potential layer, and the first potential layer and / or the second potential layer can be individually wired for each piezoelectric driving element. This ensures that the piezoelectric driving elements can be independently manipulated with different electrical signals, thereby optimizing the deformation of the carrier film, for example, according to the desired deflection behavior of the displacement element. The first potential layer and / or the second potential layer may be interrupted between two adjacent piezoelectric driving elements, thereby forming a separated potential layer segment for each driving element. According to one configuration possibility, it is conceivable that the first potential layer can be jointly wired for two or more piezoelectric driving elements, while the second potential layer can be individually wired for two or more piezoelectric driving elements, and vice versa. Efficient wiring can be achieved by jointly wiring the potential layers of multiple piezoelectric driving elements. The common potential layer may, for example, be set to 0V, while the individual potential layers are applied with independent electrical signals. Such a common potential layer may, for example, be the lower potential layer facing the carrier film. According to another configuration possibility, it is conceivable that both the first potential layer and the second potential layer can be individually wired. This allows for advantageous wiring patterns, such as connecting the first potential layer of the first driving element to the second potential layer of the second driving element, and vice versa. This wiring method can effectively achieve phase shifts between the driving signals of the driving elements, thereby obtaining deformation behavior of the carrier film that is beneficial to the deflection of the displacement element.

[0023] The present invention also relates to a MEMS loudspeaker having a MEMS component according to any of the foregoing features, and a signal processing unit for applying, receiving, and / or processing signals from the MEMS component. With this MEMS loudspeaker, a ready-to-use device is provided having an electromechanical actuator structure as a MEMS component required for sound generation, and a controller for generating sound according to a pre-given electro-audio signal. The signal processing unit can be configured, for example, as an ASIC. Due to the proposed MEMS component, the MEMS loudspeaker can achieve high acoustic power in a small size due to the significant deflection capability of the displacement element. Through the proposed carrier membrane concept, the MEMS loudspeaker is designed to be more robust against external mechanical forces.

[0024] The present invention also relates to a method for electrically manipulating a drive unit of a MEMS component according to any of the foregoing features, wherein the MEMS component has a first piezoelectric drive element and a second piezoelectric drive element, wherein the first piezoelectric drive element is manipulated by a first electrical signal oscillating around a base value, and the second piezoelectric drive element is manipulated by a second electrical signal oscillating around the base value and having a phase shift relative to the first electrical signal. This allows for optimized deflection of the displacement element through a simple manipulation mode, achieved by means of precisely tuned carrier film deformation. The base value can be a static offset value. The electrical signal can, for example, oscillate sinusoidally around the base value to obtain continuous film deformation with corresponding vibrational behavior. The drive elements can, for example, be arranged on each side of a bi-sided suspended displacement element. The drive elements can also be arranged on carrier films on different sides (e.g., upper and lower sides) of the MEMS component. Through phase shift, reverse film deformation can, for example, be achieved on different sides of the displacement element or the MEMS component.

[0025] According to one embodiment, the phase shift between the first electrical signal and the second electrical signal can be 180°. This allows for simple reverse deformation of the carrier membrane to achieve optimized deflection behavior of the displacement element.

[0026] In general, in this application, unless explicitly defined, the word “a” should not be understood as a numeral, but rather as an indefinite article meaning “at least one”. Attached Figure Description

[0027] This invention allows for various implementations, which will be described in detail below based on embodiments and in conjunction with the accompanying drawings. The following is illustrated schematically: Figure 1a / 1b shows a top view and a side sectional view along the cutting line AA of the MEMS component according to the first embodiment. Figure 2 Show Figure 1b A detailed view of the displacement element connected to the carrier film in the MEMS component shown, with enlarged representation; Figure 3 Show Figure 2 A schematic diagram of the deflection motion of the displacement element shown, with an enlarged representation; Figure 4a / 4b shows a top view and a side sectional view along the cutting line AA of the MEMS component according to the second embodiment; Figure 5a / 5b shows a top view and a side sectional view along the cutting line AA of the MEMS component according to the third embodiment. Figure 6 A side sectional view of a MEMS component according to a fourth embodiment is shown; Figure 7 A side sectional view of a MEMS component according to a fifth embodiment is shown; Figure 8 A side sectional view shows a detailed diagram of the displacement element connected to the carrier membrane in the MEMS component according to the sixth embodiment; Figure 9 A side sectional view shows a detailed diagram of the displacement element connected to the carrier membrane in the MEMS component according to the seventh embodiment; Figure 10 A schematic diagram of a MEMS loudspeaker with MEMS components is shown. Figure 11 A schematic diagram showing the signal waveforms used to control the drive unit of a MEMS component is provided. Detailed Implementation

[0028] Figure 1a and 1b A method for using according to a first embodiment is shown. Figure 10 Different views of the MEMS component 1 of the MEMS speaker 30 are shown. The partial segments shown schematically represent the components of the MEMS component 1, which can be arranged in a comparable manner and in substantially any number in a continuous side-by-side arrangement within the MEMS component 1.

[0029] MEMS component 1 has a support structure 2, which includes a substrate 21, a side frame 22, and a support beam 11 extending parallel to the substrate 21 between opposing portions of the side frame 22. For example, Figure 1b As shown, a first through-hole 3 leads to the front volume 4 of the MEMS component 1 between the supporting beam 11. Furthermore, a second through-hole 5 leads to the rear volume 6 of the MEMS component 1 in the substrate 21. Through these through-holes 3 and 5, air 26 can be drawn into the volume cavity 8 of the MEMS component 1 and released as a pressure pulse 27 into the front volume 4 and the rear volume 6.

[0030] Figure 1bAs shown, displacement elements 7 are fixed to the supporting structure 2 and are movable relative to each other. Each pair of adjacent displacement elements 7 forms a variable volume cavity 8, which can shrink and expand by the relative movement of the displacement elements 7, as indicated by the arrows on the displacement elements 7. The displacement elements 7 are fixed to the supporting beam 11 of the supporting structure 2 via the supporting membrane 10.

[0031] The MEMS component 1 also has an electrically controllable drive unit 9 for generating the movement of the displacement element 7. The drive unit 9 is equipped with a plurality of electrically controllable piezoelectric drive elements 12, which are arranged on the carrier membrane 10. Figure 1a and 1b In the illustrated embodiment, a piezoelectric drive element 12 is arranged on the bearing membrane portion 10' between each bearing beam 11 and a displacement element 7. The piezoelectric drive element 12 is configured to (in Figure 3 The deformation of the carrier membrane 10 (exemplarily shown) causes a pivoting motion 13 of the displacement element 7 connected to the carrier membrane 10 about a pivot axis 14. The pivot axis 14 extends along the fixed point of the displacement element 7 on the carrier membrane 10. The proposed carrier membrane concept achieves a stable component design with robust behavior against external mechanical influences. Furthermore, due to the flexibility of the carrier membrane 10 and the rotational flexibility of the displacement element 7, large deflections of the displacement element 7 can be achieved with low power consumption, thereby obtaining high sound pressure levels in a highly efficient manner.

[0032] Figure 1a It is also shown that the displacement element 7 has a main extension 16 along the longitudinal direction L, and the first through-hole 3 has an opening length 17 along the longitudinal direction L, which is greater than 75% of the main extension 16 of the displacement element 7, schematically corresponding to the entire main extension 16. The lateral support 25 that interrupts the through-hole 3 for reinforcing the MEMS component 1 is negligible here. The large opening length 17 allows for extensive and uniform air intake and pressure pulse output. The piezoelectric drive element 12 also has an extension range 18 along the longitudinal direction L, which is greater than 75% of the main extension 16 of the displacement element 7, schematically equal to the entire main extension 16, thus allowing for extensive film deformation over the entire film length.

[0033] Figure 2 It shows Figure 1bA detailed, enlarged view of the displacement element 7 connected to the carrier film 10 in the MEMS component 1 shown. Here, it can be seen that the carrier film 10 is anchored to two spaced-apart carrier beams 11 of the carrier structure 2. A first piezoelectric actuation element 12a is arranged on one carrier film portion 10' of the carrier film 10 between one carrier beam 11 and the displacement element 7. A second piezoelectric actuation element 12b is arranged on another carrier film portion 10' of the carrier film 10 between the other carrier beam 11 and the displacement element 7. The piezoelectric actuation elements 12a and 12b are independently electrically controllable and for this purpose have a first potential layer 19 and a second potential layer 20, respectively, through which an electric field acting on the piezoelectric actuation elements 12a and 12b can be generated to induce layer deformation therein, thereby achieving deformation of the carrier film 10. At least one of the potential layers 19 and 20 can be individually wired for each piezoelectric actuation element 12a and 12b, for example using… Figure 11 The first and second electrical signals U1 and U2 are shown in the diagram. It is conceivable, for example, that the first potential layer 19 could be used for the common wiring of the two piezoelectric drive elements 12a and 12b, such as... Figure 11 The piezoelectric drive elements 12a and 12b are connected to zero potential U0. By independently controlling the piezoelectric drive elements 12a and 12b, the deformation of the carrier membrane 10 can be precisely optimized, thereby specifically affecting the deflection behavior of the displacement element 7 connected to it.

[0034] Figure 3 The detailed diagram based on the displacement element 7 fixed to the carrier membrane 10 illustrates how the deformation of the carrier membrane 10 in the two carrier membrane portions 10' shown can be caused by appropriately manipulating the piezoelectric drive elements 12a and 12b, thereby generating a pivoting motion 13 of the displacement element 7 about a pivot axis 14 extending along the fixed point of the displacement element on the carrier membrane 10. Figure 3 As can be seen from the diagram, high deflection of the displacement element 7 can be achieved through the deformation of this bearing membrane 10, which can be used to generate high sound pressure levels.

[0035] Figure 4a and 4bA MEMS component 1 according to a second embodiment is shown, whose structure and functional principles are substantially comparable to those of the first embodiment. However, it can be seen here that the first through-hole 3 of the MEMS component 1 has an opening length 17 in the longitudinal direction L, which is less than 75% of the main extension 16 of the displacement element 7, and schematically about half of it. Therefore, the through-hole 3, which is arranged approximately centrally here, is significantly shortened, thereby allowing for improved pressure buildup in the volumetric cavity 8. The extension 18 of the piezoelectric drive element 12 in the longitudinal direction L is here interrupted by the first through-hole 3, thereby forming a drive region and a through-hole region spatially separated therefrom, wherein, for example, more drive elements 12 can be arranged side by side in the drive region compared to the first embodiment. It is conceivable that, alternatively or additionally, the second through-hole 5 could be shortened in a comparable manner.

[0036] Figure 5a and 5b A MEMS component 1 according to a third embodiment is shown, whose structure and functional principles are substantially comparable to those of the second embodiment, particularly in the design and arrangement of the first through-hole 3 and the piezoelectric drive element 12. Here, a plurality of first carrier films 10a are arranged on a first side, i.e., on the upper side 23 of the MEMS component 1, and a plurality of second carrier films 10b are arranged on a second side, i.e., on the lower side 24 of the MEMS component 1. Each first carrier film 10a is anchored to a first carrier beam 11a, and each second carrier film 10b is anchored to a second carrier beam 11b. The free end 15 of a displacement element 7 fixed to the first carrier film 10a extends toward the opposite second carrier beam 11b, while the free end 15 of a displacement element 7 fixed to the second carrier film 10b extends toward the opposite first carrier beam 11a. This achieves a compact design of the MEMS component 1 and greater displacement of air volume, as the free ends 15 of the displacement elements 7 are deflected on different sides of the MEMS component 1.

[0037] Figure 6 A MEMS component 1 according to a fourth embodiment is shown, the structure and functional principle of which are substantially comparable to those of the first embodiment. In this embodiment, the displacement element 7 is connected to the support structure 2 via a unilateral suspension, wherein each displacement element 7 is held on one side by a support beam 11 and a support membrane 10 connected thereto, thereby achieving a compact implementation of the MEMS component 1.

[0038] Figure 7 A MEMS component 1 according to a fifth embodiment is shown, whose structure and functional principles are substantially comparable to those of the third embodiment, particularly in the alternating arrangement of the upper side 23 and lower side 24 carrier films 10. Here, similar to... Figure 6The displacement element 7 is connected to the support structure 2 via a single-sided suspension, wherein each displacement element 7 is held on one side by a support beam 11 and a support membrane 10 connected thereto, thereby enabling a compact implementation of the MEMS component 1. This advantage is further enhanced by the fact that the free end 15 of each displacement element 7 extends toward the opposite support beam 11. Furthermore, since the free ends 15 of the displacement elements 7 are deflected on different sides of the MEMS component 1, displacement of a larger air volume is possible.

[0039] Figure 8 A detailed view of the displacement element 7 connected to the carrier film 10 in the MEMS component 1 according to the sixth embodiment is shown, whose structure and functional principle are substantially comparable to those of the first embodiment. Here, two independently controllable piezoelectric drive elements 12a and 12b with different dimensions in width perpendicular to the longitudinal direction L are arranged on each carrier film portion 10'. This allows for better mapping of the predetermined bending curve of the carrier film 10 when the film deforms.

[0040] Figure 9 A detailed view of the displacement element 7 connected to the carrier film 10 in the MEMS component 1 according to the seventh embodiment is shown, whose structure and functional principle are basically comparable to those of the sixth embodiment. Each carrier film portion 10' is provided with a first piezoelectric drive element 12a, a second piezoelectric drive element 12b, and a third piezoelectric drive element 12c. This allows for more precise film deformation.

[0041] Figure 10 A schematic diagram of a MEMS loudspeaker 30 is shown. The MEMS loudspeaker 30 has a MEMS component 1, which can be constructed, for example, according to any of the foregoing embodiments. The MEMS loudspeaker 30 also has a signal processing unit 31, for example configured as an ASIC, which is connected to the MEMS component 1 via a signal connection 32 and is configured to apply, receive, and / or process signals from the MEMS component 1. Due to the integration of the MEMS component 1, the MEMS loudspeaker 30 has high performance, high energy efficiency, and a compact and robust structure.

[0042] Figure 11The signal waveforms in the voltage-time diagram are schematically shown for manipulating the drive unit 9 of the MEMS component 1 using a first electrical signal U1 and a second electrical signal U2. The MEMS component 1 has a first piezoelectric drive element 12a and a second piezoelectric drive element 12b, which can be arranged, for example, on a carrier film 10 arranged on both sides of a displacement element 7 suspended on both sides. Signals U1 and U2 can be applied, for example, to a second potential layer 20 of the piezoelectric drive elements 12a and 12b, while a zero potential U0 is connected to a first potential layer 19. According to the predetermined manipulation, signals U1 and U2 oscillate around a static base value G with a phase shift P, which is 180° according to the illustrated embodiment. This allows for a simple and continuous reverse film deformation on both sides of the displacement element 7, which is beneficial for producing a significant deflection of the displacement element 7.

Claims

1. A MEMS component (1), the MEMS component being used for a MEMS loudspeaker (30), the MEMS component having: - A support structure (2) having a first through hole (3) leading to the front volume (4) of the MEMS component (1) and a second through hole (5) leading to the rear volume (6) of the MEMS component (1). - displacement elements (7) fixed to the load-bearing structure (2) and movable relative to each other, wherein A variable volume cavity (8) is constructed between each of the two adjacent displacement elements (7), and - An electrically controllable drive unit (9) for generating the motion of the displacement element (7), At least one displacement element (7) is fixed to the support beam (11) of the support structure (2) via a support membrane (10), and the drive unit (9) has at least one piezoelectric drive element (12) arranged on the support membrane (10), the piezoelectric drive element being configured to cause the displacement element (7) to pivot about a pivot axis (14) by deformation of the support membrane (10), the pivot axis extending along the fixed point of the displacement element (7) on the support membrane (10).

2. The MEMS component (1) according to claim 1, wherein The bearing membrane (10) is anchored to two spaced-apart bearing beams (11) of the bearing structure (2), and wherein the displacement element (7) is arranged between the bearing beams (11) and fixed to the bearing membrane (10).

3. The MEMS component (1) according to claim 2, wherein, At least one piezoelectric drive element (12) is arranged on the bearing membrane (10) between the spaced-apart bearing beams (11) and the displacement element (7).

4. The MEMS component (1) according to any one of the preceding claims, wherein, A first carrier film (10a) is disposed on a first side of the MEMS component (1), and a second carrier film (10b) is disposed on a second side of the MEMS component (1) opposite to the first side.

5. The MEMS component (1) according to claim 4, wherein, The first bearing membrane (10a) is anchored to the first bearing beam (11a), and the second bearing membrane (10b) is fixed to the second bearing beam (11b). The free end (15) of the displacement element (7) fixed to the first bearing membrane (10a) extends toward the second bearing beam (11b), and the free end (15) of the displacement element (7) fixed to the second bearing membrane (10b) extends toward the first bearing beam (11a).

6. The MEMS component (1) according to any one of the preceding claims, wherein, The displacement element (7) has a main extension (16) along the longitudinal direction (L), and wherein the first through hole (3) and / or the second through hole (5) has an opening length (17) along the longitudinal direction (L), the opening length being at least 75% of the main extension (16) of the displacement element (7).

7. The MEMS component (1) according to any one of the preceding claims, wherein, The piezoelectric drive element (12) has an extension range (18) along the longitudinal direction (L), which is at least 75% of the main extension (16) of the displacement element (7).

8. The MEMS component (1) according to any one of claims 1 to 5, wherein, The displacement element (7) has a main extension (16) along the longitudinal direction (L), and wherein the first through hole (3) and / or the second through hole (5) has an opening length (17) along the longitudinal direction (L), the opening length being at most 75% of the main extension (16) of the displacement element (7).

9. The MEMS component (1) according to claim 8, wherein, The extension (18) of the piezoelectric drive element (12) along the longitudinal direction (L) is interrupted by the first through hole (3) or the second through hole (5).

10. The MEMS component (1) according to any one of the preceding claims, wherein, At least two independently controllable piezoelectric drive elements (12) are arranged on the carrier membrane (10) on the same side of the displacement element (7).

11. The MEMS component (1) according to any one of the preceding claims, wherein, The drive unit (9) has at least two piezoelectric drive elements (12) formed by a layer structure having a first potential layer (19) and a second potential layer (20), wherein the first potential layer (19) and / or the second potential layer (20) can be individually wired for each piezoelectric drive element (12).

12. A MEMS loudspeaker (30) having a MEMS component (1) according to any one of the preceding claims, and having a signal processing unit (31) for applying, receiving and / or processing signals from the MEMS component (1).

13. A method for electrically controlling a drive unit (9) of a MEMS component (1) according to any one of claims 1 to 11, wherein, The MEMS component (1) has a first piezoelectric driving element (12a) and a second piezoelectric driving element (12b), wherein the first piezoelectric driving element (12a) is controlled by a first electrical signal (U1) oscillating around a base value (G), and wherein the second piezoelectric driving element (12b) is controlled by a second electrical signal (U2) oscillating around the base value (G), the second electrical signal having a phase shift (P) relative to the first electrical signal (U1).

14. The method according to claim 13, wherein, The phase shift (P) between the first electrical signal (U1) and the second electrical signal (U2) is 180°.

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