Micro-electro-mechanical system device

Abstract

The invention relates to a micro-electro-mechanical system device. A MEMS device (10) includes a transducer element (12) having a first deflectable membrane structure (14) in a vertically spaced configuration, a rigid electrode structure (16) and a second deflectable membrane structure (18) wherein the rigid electrode structure (16) is arranged between the first deflectable membrane structure and the second deflectable membrane structure, wherein the first deflectable membrane structure and the second deflectable membrane structure each comprise a deflectable portion (14-1, 18-1), and wherein the deflectable portion of the first deflectable membrane structure and the deflectable portion of the second deflectable membrane structure are mechanically coupled to each other and mechanically decoupled from the rigid electrode structure by a mechanical connection element (20); and a carrier element for supporting the transducer element; and a plurality of gripping structures (24-1,..., 24-#) for mechanically connecting the transducer element to the carrier element along the spaced-apart peripheral regions (26-1,..., 26-#) of the transducer element.

Description

Technical Field

[0001] Embodiments of the present invention relate to MEMS devices (MEMS = microelectromechanical systems). More specifically, embodiments relate to the field of MEMS acoustic transducers (MEMS microphones or MEMS speakers), such as sealed dual-membrane (SDM) microphones or speakers with a bridge design, having a plurality of (spaced-apart) clamping structures for mechanically anchoring the acoustic transducer element of the MEMS device to a carrier element along spaced-apart peripheral regions. Background Art

[0002] The sensing of environmental parameters (such as sound) in the ambient atmosphere with MEMS-based devices is becoming increasingly important in the implementation of suitable sensors within the mobile device, home automation (such as smart home), and automotive industries. MEMS devices such as MEMS acoustic transducers (MEMS microphones or MEMS speakers) essentially function as transducer elements that capacitively convert acoustic pressure waves into analog electrical signals. The acoustic conversion mechanism in a MEMS microphone includes a variable capacitor having a fixed plate (backplate or counterelectrode) and at least one deflectable plate (membrane).

[0003] When designing capacitive MEMS devices such as acoustic transducers (microphones or speakers), it is generally desirable to achieve a high signal-to-noise ratio (SNR) of the transducer output signal. The continuous miniaturization of the transducer may pose new challenges to the desired high SNR.

[0004] With the further development of semiconductor technology, sealed dual-membrane (SDM) microphones have emerged to further improve key performance characteristics such as low noise and reliability. SDM microphones generally include a top membrane, a bottom membrane, a perforated stator, a top oxide structure between the stator and the peripheral portion of the top membrane, a bottom oxide structure between the stator and the peripheral portion of the bottom membrane, and at least one post coupled between the top membrane and the bottom membrane. In a conventional SDM MEMS microphone, the transducer element is mechanically anchored by another oxide structure along its entire perimeter. Such conventional SDM MEMS microphones already have a relatively high sensitivity and SNR (signal-to-noise ratio).

[0005] Therefore, there is a continuing need in the field of MEMS devices (such as MEMS transducers) to implement MEMS devices with further improved mechanical, operational, and electrical characteristics, for example, to provide further improved performance with increased sensitivity and / or SNR of the MEMS device.

[0006] This need can be addressed by a MEMS device according to the independent claims. Additionally, specific implementation manners of the MEMS device are defined in the dependent claims. Summary of the Invention

[0007] According to one embodiment, a MEMS device includes a transducer (microphone or speaker) element having a first deflectable membrane structure, a rigid electrode structure (such as a stator or a backplate), and a second deflectable membrane structure that are vertically spaced apart. The rigid electrode structure is disposed between the first deflectable membrane structure and the second deflectable membrane structure, wherein the first deflectable membrane structure and the second deflectable membrane structure each include a deflectable portion, and wherein the deflectable portions of the first deflectable membrane structure and the second deflectable membrane structure are mechanically coupled to each other by mechanical connection elements (such as posts or cylinders) and are mechanically decoupled from the rigid electrode structure. The MEMS device further includes a carrier element for supporting the transducer element, and a plurality of clamping structures for mechanically connecting the transducer element to the carrier element along spaced-apart peripheral regions of the transducer element.

[0008] The present disclosure describes a MEMS device, which can be, for example, a MEMS acoustic transducer, such as a SDM MEMS microphone or a speaker, having a significantly increased mechanical compliance, which results in a significantly increased mechanical sensitivity (when compared to a conventional SDM microphone of the same physical size). More specifically, when compared to a conventional SDM microphone having the same physical size (coverage area or chip size), a MEMS device (e.g., in the form of a SDM microphone) having a bridge or (double-sided or multi-sided) cantilever SDM design can include a compliance (flexibility) that is approximately three times higher for a membrane arrangement having mechanically coupled first and second deflectable membrane structures 14 and 18.

[0009] Therefore, current methods for MEMS devices with a bridge design allow for the achievement of a very high compliance of the membrane arrangement, specifically, a very high compliance of the membrane arrangement of a sealed dual membrane (SDM) microphone having two coupled membrane structures, without increasing the size of the membrane arrangement (and avoiding additional manufacturing costs).

[0010] Therefore, a MEMS device with a bridge design allows for further improvement of both sensitivity and SNR, for example, further improving the performance of a SDM MEMS microphone. Specifically, high mechanical compliance (also referred to as membrane compliance or mechanical sensitivity, and defined as the displacement amplitude of the membrane per unit incident sound pressure) is an important attribute for the high operating performance of a SDM MEMS microphone. Brief Description of the Drawings

[0011] Hereinafter, embodiments of the present disclosure are described in more detail while referring to the accompanying drawings, wherein:

[0012] Figures 1A - 1C shows a schematic top (planar) view and two schematic cross-sectional views of a MEMS device according to an embodiment of the present disclosure;

[0013] Figures 2A - 2D shows a schematic top (planar) view of a MEMS device of another exemplary implementation of a bridge or cantilever design with a MEMS device (such as an SDM microphone) according to another embodiment of the present disclosure, and

[0014] Figures 3A - 3K shows a schematic diagram of different implementations of the "pillar walls" of a transducer element of a MEMS device according to other embodiments of the present disclosure.

[0015] Before discussing these embodiments in more detail with reference to the drawings, it should be noted that in the drawings and the specification, the same elements and elements having the same functions and / or the same technical or physical effects are generally provided with the same reference numerals or are identified by the same names, such that the descriptions of these elements and their functions shown in different embodiments may be interchanged or applied to each other in different embodiments. Detailed Description

[0016] In the following description, various embodiments are discussed in detail. However, it should be understood that the embodiments provide many applicable concepts that can be implemented in a wide field of dual-membrane MEMS sensors. The specific embodiments discussed merely illustrate specific ways of implementing and using the concepts, and do not limit the scope of the embodiments. In the following description of the embodiments, the same or similar elements having the same functions are provided with the same reference numerals or are identified by the same names, and the repeated description of the elements provided with the same reference numerals or identified by the same names is generally omitted. In the following description, numerous details are set forth to provide a more thorough explanation of the embodiments of the present disclosure.

[0017] However, it will be apparent to those skilled in the art that other embodiments can be practiced without these specific details. In other cases, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring the examples described herein. Additionally, the features of the different embodiments described herein can be combined with each other unless otherwise specifically noted.

[0018] It should be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can be intermediate elements. In contrast, when an element is referred to as being "directly" connected, "connected" or "coupled" to another element, there are no intermediate elements. Other terms used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" versus "directly between", "adjacent" versus "directly adjacent", and "on" versus "directly on", etc.).

[0019] For ease of description of different embodiments, the drawings include a Cartesian coordinate system x, y, z, where the x-y plane corresponds to, i.e., is parallel to, the first major surface region of the substrate ( = reference plane = x-y plane), where the direction vertically upward with respect to the reference plane (x-y plane) corresponds to the "+z" direction, and where the direction vertically downward with respect to the reference plane (x-y plane) corresponds to the "-z" direction. In the following description, the term "lateral" refers to a direction parallel to the x- and / or y-directions, i.e., a direction parallel to the x-y-plane, and where the term "vertical" refers to a direction parallel to the z-direction.

[0020] In the following description, the thickness of an element generally represents the vertical dimension of such an element. In the drawings, different elements need not be drawn to scale. Thus, the dimensions shown for different elements need not be drawn to scale.

[0021] In the description of the embodiments, terms and text paragraphs placed in parentheses (next to the element or function being described) will be understood as further explanations, exemplary configurations, exemplary additions, and / or exemplary substitutions for the element or function being described.

[0022] Figure 1A An exemplary schematic top view (parallel to the x-y plane) of an exemplary MEMS device 10 is shown illustratively, Figure 1B An exemplary schematic cross-sectional view (parallel to the x-z plane) along the cross-sectional line AA' ( = cross-sectional plane 1) of the exemplary MEMS device 10 is shown illustratively, and Figure 1C Another exemplary schematic cross-sectional view (parallel to the y-z plane) along another cross-sectional line BB' ( = cross-sectional plane 2) of the exemplary MEMS device 10 is shown illustratively.

[0023] As Figures 1A - 1CAs shown, the MEMS device 10 includes a (sound) transducer element (such as a microphone element or a speaker element) 12, which has a first deflectable membrane structure 14, a rigid electrode structure (stator or backplane) 16, and a second deflectable membrane structure 18 with a vertically spaced configuration, wherein the rigid electrode structure 16 is arranged between the first deflectable membrane structure 14 and the second deflectable membrane structure 18. The first deflectable membrane structure 14 and the second deflectable membrane structure 18 each include a deflectable portion 14-1, 18-1, and the deflectable portion 14-1 of the first deflectable membrane structure 14 and the deflectable portion 18-1 of the second deflectable membrane structure 18 are mechanically coupled to each other through a mechanical connection element (such as in the form of a post or a cylinder) 20, and are mechanically decoupled from the rigid electrode structure 16 (i.e., deflectable relative to the rigid electrode structure 16).

[0024] The MEMS device 10 further includes a carrier element 22 for supporting the transducer element 12. The carrier element 22 may include a substrate or a semiconductor (such as Si) substrate. The MEMS device 10 further includes a plurality of clamping (or anchoring) structures 24-1... 24-# for mechanically connecting (anchoring) the transducer element 12 to the carrier element 22 along the spaced-apart peripheral regions (spaced-apart clamping regions) 26-1... 26-# of the transducer element 12. Exemplarily shown in Figures 1A - 1C the MEMS device 10 in includes two (laterally opposite) clamping or anchoring structures 24-1, 24-2 for mechanically connecting (anchoring) the transducer element 12 to the carrier element 22 along the spaced-apart peripheral regions 26-1, 26-2 of the transducer element 12.

[0025] Along the (unclamped) spaced peripheral regions 27-1, 27-2 and laterally therebetween, the transducer element 12 is mechanically decoupled (unclamped) from the carrier element 22, and thus is displaceable (deflectable) relative to the carrier element 22.

[0026] More specifically, the deflectable portions 14-1 of the first deflectable membrane structure 14 and 18-1 of the second deflectable membrane structure 18 of the transducer element 12 extend between the opposing clamping (anchoring) structures 24-1, 24-2 (at the spaced-apart peripheral regions 26-1, 26-2), and are also mechanically decoupled from the carrier element 22, so as to be displaceable (deflectable) relative to the carrier element 22.

[0027] As Figures 1A - 1CAs exemplarily shown, the clamping (anchoring) structures 24-1, 24-2 along the spaced-apart peripheral regions 26-1, 26-2 and the (non-clamping) spaced-apart peripheral regions 27-1, 27-2 may include convex routes or shapes. However, the clamping (anchoring) structures 24-1, 24-2 along the spaced-apart peripheral regions 26-1, 26-2 and the (non-clamping) spaced-apart peripheral regions 27-1, 27-2 may also include, in pairs (for symmetry reasons), convex, concave or straight routes or shapes. For symmetry reasons, the clamping structures 24-1, 24-2 may be spaced equidistantly (arranged equidistantly) along the spaced-apart peripheral regions (spaced-apart clamping regions) 26-1, 26-2, and the (non-clamping) spaced-apart peripheral regions 27-1, 27-2 may also be spaced equidistantly (arranged equidistantly) along the periphery of the transducer element 12.

[0028] Thus, according to one embodiment, the (acoustic) transducer element 12 of the MEMS device 10 is mechanically anchored (coupled) along at least two peripheral regions 26-1, 26-2 of the transducer element 12 (in contrast to the transducer element of a conventional SDM MEMS microphone, in which the transducer element is mechanically anchored (constrained) along its entire periphery, like a trampoline or a tympanic membrane). Thus, embodiments of the MEMS device 10 may provide a bridge-type or (double-sided / multi-sided) cantilever-type design of the MEMS device 10, such as a bridge-type or cantilever-type design of the SDM microphone 10. This arrangement of the MEMS device 10 improves the compliance and thus improves the mechanical sensitivity of the membrane arrangement of the first and second deflectable membrane structures 14, 18 with mechanical coupling, and thus improves the overall operating performance of the MEMS device.

[0029] According to one embodiment, when compared to a conventional SDM microphone having the same physical dimensions (coverage area or chip size), the MEMS device 10 having a bridge-type or (double-sided) cantilever-type SDM design (e.g., in the form of an SDM microphone) may achieve a compliance (flexibility) of the membrane arrangement of the first deflectable membrane structure 14 and the second deflectable membrane structure 18 with mechanical coupling that is (at least) approximately three times higher.

[0030] As Figures 1A - 1BExemplarily, the MEMS device 10 may have the following typical dimensions. The coverage area (vertical projection) of the MEMS device 10 may have a first lateral dimension (= width along AA') between 0.5 mm and 2.0 mm and about 1.2 mm, and may have a second lateral dimension (= length along BB') between 0.5 mm and 2.0 mm and about 1.7 mm. The deflectable membrane structures 14, 18 may have a first lateral dimension (= width along AA') between 0.3 mm and 1.8 mm and about 0.7 mm. The rigid electrode 16 may have a first lateral dimension (= width along AA') between 0.3 and 1.8 mm and about 0.7 mm. The deflectable membrane structures 14, 18 may have a second lateral dimension (= length along BB') between 0.3 mm and 1.8 mm and about 1.2 mm. The rigid electrode 16 may have a second lateral dimension (= length along BB') between 0.3 mm and 1.8 mm and about 1.2 mm. The deflectable membrane structures 14, 18 may be vertically spaced apart by a distance between 1 μm and 10.0 μm and about 4.0 μm, and may have a thickness of about 0.2 μm to 1 μm. The rigid electrode may have a thickness of about 0.2 μm to 2 μm, and the vertical gap (spacing in the stationary (= undeflected) condition) between the opposing layers (rigid electrode - deflectable membrane) may be about 0.5 μm to 5 μm.

[0031] The terms "electrode structure" and "membrane structure" are intended to illustrate that the membrane structure and the (one or more) rigid electrode structures may respectively include a semi - conductive or conductive layer, or also include a layer sequence or layer stack having a plurality of different layers, where at least one layer is conductive, such as a (highly doped) conductive polysilicon layer or a metal layer.

[0032] Hereinafter, reference is also made to Figures 2A - 2D for describing different embodiments of the MEMS device 10 having additional geometric and structural implementations and configurations, where the additional geometric and structural implementations and configurations of the MEMS device 10 also contribute to improving the compliance of the membrane arrangement of the (acoustic) transducer element 12 having mechanically coupled first and second deflectable membrane structures 14, 18.

[0033] Figures 2A - 2D A schematic top (planar) view of the MEMS device 10 according to an additional embodiment of the present disclosure is shown, which has additional exemplary implementations of a bridge or (multiple) cantilever design of the MEMS device 10, for example in the form of an SDM transducer (microphone or speaker).

[0034] As Figure 2A exemplarily shown in, the (acoustic) transducer element 12 having a membrane arrangement may include a rectangular shape (in the lateral plane), the membrane arrangement having mechanically coupled first and second deflectable membrane structures 14, 18.

[0035] The clamping (anchoring) structures 24-1, 24-2 along the spaced-apart peripheral regions (spaced-apart clamping regions) 26-1, 26-2 and the (non-clamped) spaced-apart peripheral regions 27-1, 27-2 may include straight routes or shapes, resulting in a rectangular (lateral) shape of the coverage area (substrate area) of the (acoustic) transducer element 12 (see Figure 2A the solid lines). However, the clamping (anchoring) structures 24-1, 24-2 along the spaced-apart peripheral regions 26-1, 26-2 and the (non-clamped) spaced-apart peripheral regions 27-1, 27-2 may also include convex, concave or straight routes or shapes in pairs (for symmetry reasons) (see also Figure 2A the dashed lines).

[0036] Thus, Figure 2A the MEMS device 10 of

[0037] Thus, as Figure 2A exemplarily shown in Figure 2A the MEMS device 10 may include a transducer element 12, which may have a polygonal shape with an even number of sides or edges. The shape of the transducer element 12 may also be a simple convex polygon. As

[0038] As Figures 2B - 2D exemplarily shown in

[0039] Figure 2B exemplarily shown, the (acoustic) transducer element 12 with a membrane arrangement may include a multi-arm configuration having mechanically coupled first and second deflectable membrane structures 14, 18.

[0040] Figure 2BThe exemplary construction can also be applied to any odd number (2N + 1, where N = 1, 2, 3, 4...) of arms, where the clamping (anchoring) structures 24-1... 24-# (here: # = 2N + 1) along the spaced peripheral regions 26-1... 26-# can also (for all regions, for example, for symmetry reasons) include convex, concave or straight routes or shapes, and where the (unclamped) spaced peripheral regions 27-1... 27-# (# = 2N + 1) can also (for at least paired or all regions, for example, for symmetry reasons) include convex, concave or straight routes or shapes.

[0041] Figure 2C Exemplarily, a four-arm structure is shown, where the transducer element 12 can be clamped or mechanically anchored to the carrier element (or substrate) 22 along four sides, and where there are four clamping or anchoring structures 24-1, 24-2, 24-3, 24-4 along the spaced peripheral regions 26-1, 26-2, 26-3, 26-4.

[0042] Figure 2C The exemplary construction can also be applied to any even number (2N where N = 2, 3, 4...) of arms, where these clamping (anchoring) structures 24-1... 24-# and the (unclamped) spaced peripheral regions 27-1... 27-# along the spaced peripheral regions 26-1... 26-# (here: # = 2N) can also (for at least paired or all regions, for example, for symmetry reasons) include convex, concave or straight routes or shapes.

[0043] Figure 2D Exemplarily, a circular (e.g., circular, oval or elliptical) construction of the (acoustic) transducer element 12 is shown, where the transducer element 12 can be clamped or mechanically anchored to the carrier element (or substrate) 22 along a plurality of (e.g., at least four) peripheral segments, and there are clamping or anchoring structures 24-1... 24-# along (e.g., at least four) spaced peripheral regions 26-1... 26-#.

[0044] The transducer element 12 can include various shapes, where the list of shapes of the transducer element 12 exemplarily shown in Figures 1A - 1C and Figures 2A - 2D should not be considered exhaustive, and the additional geometric and structural implementations and constructions of the MEMS device 10 described below can further contribute to improving the compliance of the membrane arrangement of the (acoustic) transducer element 12 with the first and second deflectable membrane structures 14, 18 having mechanical coupling.

[0045] According to an embodiment, as Figures 1A - 1C and Figures 2A - 2DExemplarily, the combined length of the clamping structures 24-1 …… 24-# along the periphery of the transducer element 12 can be equal to or less than (≤) 50% of the (total) peripheral length L of the transducer element 12. Additionally, the lateral bisectors 30 passing through each clamping region (spaced peripheral regions) 26-1 …… 26-# can pass through the geometric center region (or point) 28 of the transducer element 12.

[0046] According to one embodiment, the geometric center region 28 can have a lateral extension around the geometric center point “C” of the transducer element 12, which can be less than 1%, 3%, or 5% of the total lateral extension (or diameter) “D” of the transducer element 12.

[0047] According to an embodiment, as Figures 1A - 1C and Figures 2A - 2D Exemplarily shown, the clamping regions 26-1 …… 26-# can be spaced equidistantly (arranged equidistantly) along the periphery of the transducer element 12. The equidistant peripheral regions 27-1 …… 27-# (not clamped) are arranged along the periphery of the transducer element 12 between the equidistant clamping regions 26-1 …… 26-#.

[0048] According to an embodiment, as Figures 1A - 1C and Figure 2A 、 Figure 2C 、 Figure 2D Exemplarily shown as in, the plurality of clamping structures 24-1 …… 24-# can include 2N clamping structures, where N = 1, 2, 3, 4 ……, and the corresponding lateral bisectors 30 pass through two opposite clamping regions (spaced peripheral regions) 26-1, 26-2 …… 26-# and the geometric center region 28 of the transducer element 12.

[0049] According to an embodiment, as Figure 2B and Figure 2D Shown, the plurality of clamping structures 24-1 …… 24-# can include 2N + 1 clamping structures, where N = 1, 2, 3, 4 ……, and each lateral symmetry axis of the transducer element 12 passes through the clamping structures 24-1 …… 24-# and the geometric center region 28 of the transducer element 12.

[0050] According to one embodiment, as Figures 1A - 1C and Figures 2A - 2D Exemplarily shown, the (acoustic) transducer element 12 of the MEMS device 10 can have a microphone and / or speaker function. Thus, the MEMS device 10 can be implemented as a MEMS microphone or a MEMS speaker, such as a sealed dual-membrane (SDM) microphone or speaker with a bridge design.

[0051] The microphone is used to sense or detect ambient sound. The speaker is used to emit acoustic or ultrasonic waves into the environment. Thus, the acoustic transducer element 10 can be formed as a sensor (e.g., a microphone or a pressure sensor) or an actuator (e.g., a speaker).

[0052] In the case where the acoustic transducer element 12 is implemented as a capacitive sensor, the deflection ±Δz of the membrane arrangement having the first deflectable membrane structure 14 and the second deflectable membrane structure 18 with mechanical coupling is based on the applied external pressure load. The deflection or displacement ±Δz of the deflectable membrane device can then be detected and capacitively read out in order to provide a corresponding (analog or AD-converted digital) output signal of the acoustic transducer element 12. The deflection ±Δz of this deflectable membrane arrangement is (generally) caused by acoustic (sound) pressure variations in the environment.

[0053] According to another embodiment, the acoustic transducer element 12 can also be implemented as an actuator, for example in the form of a speaker (due to its operating mode), which uses the capacitive effect to generate sound. An initial mechanical movement of the deflectable membrane device is generated by applying a (modulated) voltage between the first and second deflectable membrane structures 14, 18, where this movement is generally converted into audible sound or ultrasonic waves.

[0054] Hereinafter, reference is also made to Figures 1A - 1C and Figures 2A - 2D for different embodiments of the MEMS device 10 implemented as a MEMS microphone or a MEMS speaker, such as a sealed dual membrane (SDM) microphone or speaker having a bridge design. The bridge design of the described MEMS device 10 improves the compliance and thus the mechanical sensitivity of the membrane arrangement having the first and second deflectable membrane structures 14, 18 with mechanical coupling, and thus improves the overall operating performance of the MEMS device in the form of a MEMS microphone or a MEMS speaker (e.g., a sealed dual membrane (SDM) microphone or speaker).

[0055] According to an embodiment, the (acoustic) transducer element 12 can be arranged on (above) an opening (void or cavity) 32 in a carrier element 22 (e.g., a substrate or a frame structure), to which the (acoustic) transducer element 12 can be attached. The deflectable portion 18-1 of the second deflectable membrane structure 18 can face the opening 32 in the carrier element (substrate or frame structure) 22.

[0056] The openings 32 in the carrier element 22 may have a shape or path that is substantially the same or slightly laterally offset (enlarged) in a vertical projection at the (unclamped) spaced-apart peripheral regions 27-1 …… 27-# of the transducer element 12, to allow for a deflection ±Δz of the membrane arrangement of the first and second deflectable membrane structures 14, 18 with mechanical coupling (i.e., to allow a deflection ±Δz of the deflectable portions 14-1, 18-1 of the first and second deflectable membrane structures 14, 18).

[0057] According to one embodiment, the rigid electrode structure 16 may be formed as a perforated stator or backplane relative to the first deflectable membrane structure 14 and the second deflectable membrane structure 18.

[0058] Due to the bridge design of the MEMS device 10, the rigid electrode structure 16 can be mechanically clamped to the carrier element 22 at the clamping regions 26-1 …… 26-# by the clamping structures 24-1 …… 24-#, and can be mechanically decoupled (deflectable relative to the carrier element 22) from the carrier element 22 along the (unclamped) spaced-apart peripheral regions 27-1, 27-2. When the membrane arrangements 14, 18 of the transducer element 12 with the mechanically coupled first and second deflectable membrane structures 14, 18 are arranged, for example, above the openings 32 in the carrier element 22, the deflectable portions 14-1, 18-1 of the membrane arrangements 14, 18 of the transducer element 12 are mechanically decoupled (unclamped) from the carrier element 22 and are thus displaceable (deflectable) relative to the carrier element 22.

[0059] Each clamping structure 24-…… 4-# may include a first isolation element 24-A between the peripheral portion of the stator 16 and the peripheral portion of the top membrane 14, a second isolation element 24-B between the peripheral portion of the stator 16 and the peripheral portion of the bottom membrane 18, wherein the transducer element 12 is mechanically anchored to the carrier element 22 by a third isolation element 24-C of the clamping structures 24-1 …… 24-#. Different isolator elements (e.g., oxide elements or layers) 24-A, 24-B, 24-C of the clamping structures 24-1 …… 24-# are provided for mechanically fixing the boundary regions of the membranes 14, 18 and the stator 16 relative to the carrier element 22.

[0060] Furthermore, the transducer element 12 of the MEMS device 10 includes wall elements (pillar walls) 29-1 …… 29-# at the (unclamped) spaced-apart peripheral regions 27-1 …… 27-#, wherein along the (unclamped) spaced-apart peripheral regions 27-1 …… 27-# and laterally between the (unclamped) spaced-apart peripheral regions 27-1 …… 27-#, the transducer element 12 is mechanically decoupled (unclamped) from the carrier element 22 and is thus displaceable (deflectable) relative to the carrier element 22.

[0061] The wall elements (column walls) 29-1 …… 29-# may include the same material as the mechanical connection elements (columns or cylinders) 20. In addition, the wall elements (column walls) 29-1 …… 29-# may include the same (lateral) thickness and (vertical) height as the mechanical connection elements 20. Thus, the wall elements (column walls) 29-1 …… 29-# may be regarded as line elements in the vertical projection, while the mechanical connection elements may be regarded as point elements in the vertical projection.

[0062] As Figures 1A - 1C and Figures 2A - 2D Exemplarily shown, the clamping structures 24-1 …… 24-# and the wall elements (column walls) 29-1 …… 29-# form a circumferential wall structure 40 along the periphery of the transducer element 12, wherein the circumferential wall structure 40 defines a cavity 36 with respect to the environment 48.

[0063] As Figures 1A - 1C and Figures 2A - 2D Exemplarily shown, the MEMS device 10 includes (as part of the circumferential wall structure 40) at least two clamping or anchoring structures 24-1 …… 24-# for mechanically connecting (anchoring) the transducer element 12 to the carrier element 22 along the spaced-apart peripheral regions 26-1 …… 26-# of the transducer element 12.

[0064] In addition, the wall elements (column walls) 29-1 …… 29-# of the MEMS device 10 (as another part of the circumferential wall structure 40) form (unclamped) spaced-apart peripheral regions 27-1, 27-2, wherein along the (unclamped) spaced-apart peripheral regions 27-1, 27-2 and laterally therebetween, the transducer element 12 is mechanically decoupled (unclamped) from the carrier element 20 and is thus displaceable (deflectable) with respect to the carrier element 20.

[0065] According to one embodiment, the sealed cavity 36 may include a low-pressure region. Compared with the ambient atmosphere, the low-pressure region located within the sealed cavity 36 may include a reduced atmospheric pressure, wherein for example, the reduced atmospheric pressure in the low-pressure region may be a vacuum or near vacuum.

[0066] The low-pressure region may have an atmospheric pressure that is less than the ambient pressure or standard atmospheric pressure. More specifically, according to one embodiment, the pressure in the low-pressure region may be substantially a vacuum or near vacuum. Alternatively, the pressure in the low-pressure region may be less than about 50% (or 40%, 25%, 10% or 1%) of the ambient pressure or standard atmospheric pressure. Standard atmospheric pressure is typically 101.325 kPa or 1013.25 mbar. The pressure in the low-pressure region may also be expressed as an absolute pressure, for example less than 50, 40, 30 or less than 10 kPa.

[0067] AsFigures 1A - 1C and Figures 2A - 2D As shown in Figures 2A - 2D , the transducer element 12 of the MEMS device 10 may have straight or slightly curved (slightly recessed or slightly protruding) wall elements (pillar walls) 29-1... 29-#.

[0068] Hereinafter, Figures 3A - 3K Schematic diagrams showing different implementations of the wall elements (pillar walls) 29-1... 29-# of the transducer element 12 of the MEMS device 10 according to other embodiments of the present disclosure are exemplarily shown.

[0069] According to one embodiment, at least one, a plurality, or all of the wall elements 29-1... 29-# may include corrugated wall sections (wall corrugations) 42-1... 42-#, such as at least one or more of the at least one or more corrugated wall sections 42-1... 42-#. The wall elements 29-1... 29-# of the transducer element 12 form pillar walls at the periphery (boundary region) of the transducer element 12 disposed between the deflectable portion 14-1 of the first deflectable membrane structure 14 and the deflectable portion 18-1 of the second deflectable membrane structure 18. The wall elements 29-1... 29-# are mechanically decoupled from the rigid electrode structure 16.

[0070] (One or more) (corresponding) corrugated wall sections (wall corrugations) 42-1... 42-# may have a curved (wavy), circular, sinusoidal, or semi-circular shape, for example, a circular, oval, or elliptical section shape in a vertical projection (top view). Additionally or alternatively, (one or more) (corresponding) corrugated wall sections (wall corrugations) 42-1... 42-# may have a square, rectangular, triangular, or serrated shape in a vertical projection (top view). The corrugated wall sections 42-1, 42-3... may extend into the cavity 36, for example, may be bent inward (recessed) into the cavity 36. Additionally or alternatively, the corrugated wall sections 42-2, 42-4... may emerge (protrude) from the cavity 36, for example, may be bent outward (protruding) from the cavity 36.

[0071] (One or more) corrugated wall sections 42-1... 42-# may be arranged to reduce the tensile stress in the wall elements 29-1... 29-# of the transducer element 12, and based on the reduced tensile stress, the overall compliance of the membrane (= the overall compliance of the transducer element 12) may be increased. (One or more) corrugated wall sections 42-1... 42-# form an extension or elongation of the corresponding wall elements 29-1... 29-# relative to the peripheral line of the transducer element 12.

[0072] The corrugated wall sections 42-1……42-# can be arranged on two opposite wall elements 29-1……29-# of the "arms" of the transducer element 12. In addition, the corrugated wall sections 42-1……42-# can be symmetrically arranged in the central region of the "arms" of the transducer element 12, or can be symmetrically arranged in the central region between two opposite clamping structures 24-1……24-# of the transducer element 12, for example, spaced equidistantly from two opposite clamping structures 24-1……24-# of the transducer element 12. As a result, the corrugated column walls 29-1……29-# can (at least partially) relieve (reduce) the tensile stress caused by wall elongation, making the overall compliance of the transducer element 12 of the MEMS device 10 higher.

[0073] Reference Figures 3A - 3K , different embodiments of the MEMS device 10 with additional geometric and structural implementations and configurations are now described, wherein the additional geometric and structural implementations and configurations of the MEMS device 10 contribute to improving the compliance of the (acoustic) transducer element 12 (membrane arrangement) of the first and second deflectable membrane structures 14, 18 with mechanical coupling.

[0074] Figure 3A A schematic cross-sectional 3D view of a part (section) of the transducer element 12 of an exemplary MEMS device 10 is exemplarily shown, and Figures 3B - 3K Another schematic top view (parallel to the x-y plane) of a part (section) of the transducer element 12 of an exemplary MEMS device 10 is exemplarily shown. As Figures 3A - 3J exemplarily shown therein, the section line AA' (= section plane 1) of the exemplary MEMS device 10 (e.g., see Figures 1A - 1B ) can pass through the center of the (one or more) corrugated wall sections 42-1……42-#, or can be parallelly offset to the center of the (one or more) corrugated wall sections 42-1……42-#.

[0075] As Figure 3A exemplarily shown therein, the wall element (column wall) 29-1 can include a single corrugated wall section 42-1, wherein the corrugated wall section 42-1 includes a curved, circular, sinusoidal or semi-circular shape in a vertical projection (top view), which extends in the direction into the cavity 36, i.e., bends inward into the cavity 36. Thus, the corrugated wall section 42-1 forms a lateral elongation (extension) of the wall element 29-1. For example, the corrugated wall section 42-1 can have a section shape that is circular, oval or elliptical (in a vertical projection). Alternatively, the corrugated wall section 42-1 can have a square, rectangular, triangular or serrated shape.

[0076] As Figure 3BExemplarily shown, the wall element (column wall) 29-1 can include a single corrugated wall section 42-2, where the corrugated wall section 42-2 includes (in a vertical projection) a curved, circular, sinusoidal or semi-circular shape, which extends in the direction of emerging from the cavity 36, i.e., bends outward from the cavity 36. Thus, the corrugated wall section 42-2 forms a lateral elongation (extension) of the wall element 29-1 extending outward from the cavity 36. The corrugated wall section 42-2 can have, for example, a circular, oval or elliptical section shape in a vertical projection (top view). Alternatively, the corrugated wall section 42-2 can have a square, rectangular, triangular or serrated shape.

[0077] Figure 3C Exemplarily shown is a configuration of a wall element (column wall) 29-1 including a plurality (e.g., three) of corrugated wall sections 42-1, 42-3, 42-5, where the corrugated wall sections 42-1, 42-3, 42-5 are laterally spaced from each other along the perimeter of the transducer element 12 by intermediate wall elements (spacers) 42-0. The corrugated wall sections 42-1, 42-3, 42-5 can include (in a vertical projection) a curved, circular, sinusoidal or semi-circular shape, and extend in the direction into the cavity 36, i.e., bend inward into the cavity 36. Thus, the corrugated wall sections 42-1, 42-3, 42-5 form a lateral elongation (extension) of the wall element 29-1. The corrugated wall sections 42-1, 42-3, 42-5 can have, for example, a circular, oval or elliptical section shape in a vertical projection. Alternatively, the corrugated wall sections can have a square, rectangular, triangular or serrated shape.

[0078] As Figure 3D exemplarily shown therein, the wall element (column wall) 29-1 can include a plurality (e.g., three) of corrugated wall sections 42-2, 42-4, 42-6. The corrugated wall sections 42-2, 42-4, 42-6 can include (in a vertical projection) a curved, circular, sinusoidal or semi-circular shape, and can extend in the direction of emerging from the cavity 36, i.e., bend outward from the cavity 36. In addition, intermediate wall elements (spacers) 42-0 are arranged along the perimeter of the transducer element 12 between the plurality of corrugated wall sections 42-2, 42-4, 42-6. Thus, the corrugated wall sections 42-2, 42-4, 42-6 form a lateral extension of the wall element 29-1 extending outward from the cavity 36. The corrugated wall sections 42-2, 42-4, 42-6 can have, for example, a circular, oval or elliptical section shape in a vertical projection. Alternatively, the corrugated wall sections 42-2, 42-4, 42-6 can have a square, rectangular, triangular or serrated shape.

[0079] As Figure 3EExemplarily shown, the wall element (column wall) 29-1 may include two corrugated wall sections 42-1, 42-2, wherein the corrugated wall sections 42-1, 42-2 include a curved, circular, sinusoidal or semi-circular shape (in a vertical projection). As Figure 3E shown, the corrugated wall section 42-1 extends in the direction into the cavity 36 (curving inwards into the cavity 36), wherein the corrugated wall section 42-2 extends in the direction away from the cavity 36 (curving outwards from the cavity 36). Thus, the corrugated wall sections 42-1, 42-2 form an elongation of the wall element (column wall) 29-1 in an "S"-shaped configuration. According to one embodiment, the corrugated wall sections 42-1, 42-2 may optionally be spaced apart from each other by an intermediate wall element (spacer) 42-0 (as described with respect to Figures 3C - 3D ). The corrugated wall sections 42-1, 42-2 may have a section shape, for example, circular, oval or elliptical in a vertical projection. Alternatively, the corrugated wall sections 42-1, 42-2 may have a square, rectangular, triangular or serrated shape.

[0080] As Figure 3F shown, the wall element (column wall) 29-1 may include a plurality of corrugated wall sections 42-1... 42-6, wherein the corrugated wall sections 42-1... 42-6 include a curved, circular, sinusoidal or semi-circular shape. As Figure 3F shown, the corrugated wall sections 42-1, 42-3, 42-5 extend in the direction into the cavity 36 (curving inwards into the cavity 36), wherein the corrugated wall sections 42-2, 42-4, 42-6 extend in the direction away from the cavity 36 (curving outwards from the cavity 36). Thus, the corrugated wall sections 42-1... 42-6 form an extension of the wall element (column wall) 29-1 in a multiple (e.g., triple) "S"-shaped configuration. According to one embodiment, the corrugated wall sections 42-1... 42-6 may optionally be separated from each other by an intermediate wall element (spacer) 42-0 (as described with respect to Figures 3C - 3D ). The corrugated wall sections 42-1... 42-6 may have a section shape, for example, circular, oval or elliptical in a vertical projection. Alternatively, the corrugated wall sections 42-1... 42-6 may have a square, rectangular, triangular or serrated shape.

[0081] As Figures 3G - 3H shown, the wall element (column wall) 29-1 may include a single corrugated wall section 42-1 (which has been described in Figure 3A ). As Figures 3G - 3H further shown, the deflectable portions 14-1 of the first deflectable membrane structure 14 of the transducer element 12 and the deflectable portions 18-1 of the second deflectable membrane structure 18 may include recesses (notches or grooves) 44, wherein in a vertical projection, the shape of the recesses 44 extends (substantially) parallel to the shape of the corrugated wall section 42-1. Figure 3GThe groove 44 of Figure 3H is wider (larger) than the groove 44 of Figure 3G Therefore, the width w of the boundary region 46 at the corrugated wall section 42-1 of 46 is less than the width w of the boundary region 46 at the corrugated wall section 42-1 of Figure 3H 46 .

[0082] In addition to the elongation of the wall element 29-1 through the corrugated wall section 42-1, the depressions 44 in the deflectable part 14-1 of the first deflectable membrane structure 14 and the deflectable part 18-1 of the second deflectable membrane structure 18 of the transducer element 12 form corresponding elongations of the peripheral line of the transducer element 12. Therefore, the total compliance of the transducer element 12 of the MEMS device 10 can be further increased.

[0083] As Figures 3I - 3J exemplarily shown, the bridge design of the MEMS device 10 provides lateral ventilation through the ventilation slits 50 in the unclamped peripheral regions 27-1, 27-2 and thus allows lateral air exchange to equalize (as a low-pass function) slow (static, e.g., temperature-related) ambient pressure changes between two vertically opposite sides of the acoustic transducer element 12.

[0084] Figure 3I An exemplary embodiment is shown, in which the ventilation slit 50, for example between a fixed element 22 such as a substrate and the transducer element 12, has a straight or slightly curved path that follows (is parallel to) the path of the wall element (column wall) 29-1. Figure 3I An exemplary embodiment is shown, in which the ventilation slit 50 also runs along (is parallel to) the path of the wall element (column wall) 29-1 having the corrugated wall section 42-1 and the depression 44. The fixed element 22 may have a lateral extension 22-1 corresponding to Figures 3G - 3H the depression 44.

[0085] As described exemplary with reference to Figures 3A - 3J and Figure 3K (sinusoidal), the wall elements 29-1... 29-# may include corrugated wall sections (wall corrugations) 42-1... 42-#, which have a curved, circular, sinusoidal or semi-circular shape, for example a circular, oval or elliptical section shape in a vertical projection (top view).

[0086] As Figure 3K ​(Square-Triangle-Sawtooth) As shown by way of example, (one or more) (corresponding) corrugated wall segments 42-1...42-# may alternatively have a square (rectangular), triangular or sawtooth shape in vertical projection. The corrugated wall segments 42-1, 42-3... may extend into the cavity 36. Alternatively or additionally, (one or more) corrugated wall segments 42-2, 42-4... may emerge (protrude) from the cavity 36.

[0087] The above about Figures 3A - 3J The description of (one or more) wall elements 29-1...29-# having at least one curved, circular, sinusoidal or semicircular shape of the corrugated wall segment 42-1...42-# also applies to (one or more) wall elements 29-1...29-# having at least one square, rectangular, triangular or serrated shape of the corrugated wall segment 42-1...42-#.

[0088] According to one embodiment, the mechanical connection element 20 may include a post or cylinder shape between the two opposing deflectable membrane structures 14 , 18 .

[0089] According to one embodiment, the plurality of (pillar or cylindrical) mechanical connection elements 20 may be non-conductive, for example, in order to implement the first and second membrane structures 14, 18 as two electrically separated electrodes for differential (readout) operation, i.e. to allow a differential readout configuration of the first and second membrane structures 14, 18. Thus, the pillars may be at least partially made of an insulating material, wherein the pillars 20 may be made of an insulating material, such as silicon, nitride, silicon oxide, polymer or a combination of the aforementioned materials, or a combination of the aforementioned materials with a conductive layer (e.g. silicon), as long as the conductive part of the pillars is separated from the membrane structures 14, 18 by an insulating material.

[0090] According to another embodiment, the plurality of (pillar-shaped or cylindrical) mechanical connection elements 20 may be electrically conductive, for example in order to achieve an electrical connection of the first and second membrane structures 14 , 18 as two electrically connected electrodes.

[0091] According to one embodiment, Figures 1A - 1C and Figures 2A - 2D As shown by way of example, the (acoustic) transducer element 12 of the MEMS device 10 is implemented as a MEMS microphone or a MEMS loudspeaker having a bridge design, for example a sealed dual membrane (SDM) microphone.

[0092] In summary, the (sealed) dual or multi-MEMS microphone 10 with a (vacuum) cavity 36 relies on a plurality of mechanical connection elements, also known as posts or cylinders 20, which connect two membrane structures 14, 18 (in the case of a dual-membrane arrangement) and prevent the membrane structures 14, 18 from collapsing due to pressure loads on the two membrane structures 14, 18 (i.e., the external pressure on the top of the top membrane structure 14 and the external pressure on the bottom of the bottom membrane structure 18).

[0093] The mechanical connection elements 20 of the dual-membrane MEMS microphone 10 are equally applicable to multi-MEMS microphones 10 with three or more membrane structures, where adjacent membrane structures are mechanically coupled by the mechanical connection elements 20. In the case where the MEMS device 10 is formed as a multi-MEMS microphone with three membrane structures, the MEMS device 10 may include first and second rigid electrode structures and first to third deflectable membrane structures in a vertically spaced configuration (e.g., a vertically separated and spaced configuration). The first rigid electrode structure is sandwiched between the first and second deflectable membrane structures, where the second rigid electrode structure is sandwiched between the second and third deflectable membrane structures. The first, second, and third deflectable membrane structures each include a deflectable portion, where the deflectable portions of the first, second, and third deflectable membrane structures are mechanically coupled to each other by the mechanical connection elements 20 and are mechanically decoupled from the first and second rigid electrode structures. This arrangement of the MEMS device 10 can also be applied to multi-MEMS microphones with four or more membrane structures.

[0094] As Figures 1A - 1C and Figures 2A - 2D exemplarily shown, the transducer element is depicted in its rest position, e.g., when no sound waves reach the deflectable membrane structures. Incident sound waves can cause the deflectable portions of the membrane structures 14-1, 18-1 to deflect. Additionally, the two deflectable membrane structures 14-1, 18-1 can be exposed to ambient pressure and potential sound pressure. The top side of the first deflectable membrane structure 14-1 can also be considered the main sound-receiving surface of the MEMS device 10. Additionally, the bottom side of the second deflectable membrane structure 18 can also be considered the main sound-receiving surface of the MEMS device 10. When sound waves are incident on the membrane structures 14, 18, the membrane structures 14, 18 can deflect or oscillate. The displacement of one membrane (either of the two membrane structures 14-1, 18-1) can cause a corresponding displacement of the second membrane, and vice versa. It should be noted that according to multiple embodiments, the membrane structures 14-1, 18-1 can deflect in response to pressure changes caused by incident sound waves. An electrical signal can be generated by the deflection of the membrane structures 14-1, 18-1, and the electrical signal can be read out by a plurality of readout circuits. The readout circuits can process the electrical signal and can ultimately convert the electrical signal into useful information as a possible final step in signal processing.

[0095] Figures 2A - 2DShows different exemplary schematic top (planar) views of a MEMS device 10 and some possible implementations for improving mechanical compliance or mechanical sensitivity. The shape of the transducer element 12 can be selected or optimized for various objectives and their combinations (e.g., chip size, capacitance, motor sensitivity, resonance frequency, etc.). Specifically, the shape and design of the transducer element 12 can even be optimized such that mechanical compliance requirements can be achieved. The transducer element 12 can include a variety of shapes, and the list of shapes of the transducer element 12 should not be considered exhaustive.

[0096] In addition, Figures 2A - 2D Shows that a plurality of clamping or mechanical anchoring structures 24-1, 24-2... 24-# spaced apart along the peripheral region (clamping region) 26-1, 26-2... 26-# of the transducer element 12 can be supported by a carrier element (or substrate) 22. The number of regions along which the transducer element 12 is clamped to the substrate 22 can be at least two or more. According to another embodiment, the line bisecting the spaced-apart peripheral regions (clamping regions) 26-1, 26-2... 26-# can coincide with the (lateral) axis of symmetry of the transducer element 12.

[0097] Describes other embodiments and aspects that can be used alone or in combination with the features and functions described herein.

[0098] According to one embodiment, a MEMS device includes a transducer element having a first deflectable membrane structure, a rigid electrode structure (stator), and a second deflectable membrane structure in a vertically spaced-apart configuration, wherein the rigid electrode structure is disposed between the first deflectable membrane structure and the second deflectable membrane structure, wherein the first deflectable membrane structure and the second deflectable membrane structure each include a deflectable portion, and wherein the deflectable portions of the first deflectable membrane structure and the second deflectable membrane structure are mechanically coupled to each other and mechanically decoupled from the rigid electrode structure by mechanical connection elements; and a carrier element for supporting the transducer element; and a plurality of clamping structures for mechanically connecting the transducer element to the carrier element along spaced-apart peripheral regions of the transducer element.

[0099] According to one embodiment, the combined length of the clamping structures along the periphery of the transducer element is equal to or less than (≤) 50% of the peripheral length of the transducer element, and wherein the lateral bisecting line passing through each clamping region passes through the geometric center region of the transducer element.

[0100] According to one embodiment, the clamping regions are spaced apart equidistantly along the periphery of the transducer element.

[0101] According to one embodiment, the plurality of clamping structures includes 2N clamping structures, where N = 1, 2, 3, 4..., and where the corresponding lateral bisecting line passes through two opposite clamping regions and the geometric center region of the transducer element.

[0102] According to one embodiment, the plurality of clamping structures includes 2N + 1 clamping structures, where N = 1, 2, 3, 4..., and where the respective lateral symmetry axes of the transducer element pass through the clamping structures and the geometric center region of the transducer element.

[0103] According to one embodiment, the geometric center region has a lateral extension around the geometric center of the transducer element, and the lateral extension is not less than 5% of the diameter of the transducer element.

[0104] According to one embodiment, the first and second deflectable membrane structures form a cavity relative to the environment, and the cavity is sealed relative to the environment.

[0105] According to one embodiment, the clamping structures at the spaced-apart peripheral regions of the transducer element and the wall elements at the unclamped, spaced-apart peripheral regions of the transducer element form an annular wall structure along the periphery of the transducer element, and the annular wall structure laterally defines a cavity relative to the environment.

[0106] According to one embodiment, the cavity includes a low-pressure region, where the low-pressure region includes a reduced atmospheric pressure compared to the ambient atmosphere, and where, for example, the reduced atmospheric pressure in the low-pressure region is a vacuum or near-vacuum.

[0107] According to one embodiment, at least one or all of these wall elements include (at least one or more) corrugated wall sections.

[0108] According to one embodiment, the corrugated wall section has a curved, circular, sinusoidal, or semi-circular shape, for example, a circular, oval, or elliptical section shape, or where the corrugated wall section has a square, rectangular, triangular, or serrated shape.

[0109] According to one embodiment, the corrugated wall section extends into the cavity and / or protrudes from the cavity.

[0110] According to one embodiment, the mechanical connection elements include a plurality of columnar or cylindrical mechanical connection elements between two opposite deflectable membrane structures.

[0111] According to one embodiment, the plurality of columnar or cylindrical mechanical connection elements are non-conductive.

[0112] According to one embodiment, the rigid electrode structure forms a counter electrode (stator) relative to the first and second deflectable membrane structures.

[0113] According to one embodiment, the transducer element has a microphone and / or speaker function.

[0114] While some aspects have been described as features in the context of a device, it is apparent that such a description can also be regarded as a description of the corresponding features of a method. While some aspects have been described as features in the context of a method, it is clear that such a description can also be regarded as a description of the corresponding features regarding the functions of a device.

[0115] According to certain implementation requirements, embodiments of the control circuit can be implemented in hardware or software or at least partly in hardware or at least partly in software. Generally, embodiments of the control circuit can be implemented as a computer program product having program code that, when the computer program product runs on a computer, the program code is operable to execute one of the methods. The program code can be stored, for example, on a machine-readable carrier.

[0116] In the foregoing detailed description, it can be seen that, for the purpose of simplifying the present disclosure, various features are combined in the examples. The methods of the present disclosure should not be construed as reflecting an intention that the claimed examples require more features than those expressly recited in each claim. On the contrary, as reflected by the following claims, the subject matter may lie in less than all of the features of a single disclosed example. Thus, the following claims are hereby incorporated into the detailed description, where each claim can stand on its own as a separate example. Although each claim can stand on its own as a separate example, it should be noted that while a dependent claim can refer to a particular combination with one or more other claims in the claims, other examples can also include combinations of the dependent claim with the subject matter of each other dependent claim or combinations of each feature with other dependent claims or independent claims. Such combinations are presented herein unless it is stated that a particular combination is not desired. In addition, even if the claim does not directly depend on the independent claim, the features of the claim are intended to be included in any other independent claim.

[0117] Although specific embodiments have been shown and described herein, those of ordinary skill in the art will understand that various alternative and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present embodiment. This application is intended to cover any modifications or variations of the specific embodiments discussed herein. Thus, it is intended that the embodiments be limited only by the claims and their equivalents.

Claims

1. A MEMS device (10), comprising: A transducer element (12) having a first deflectable membrane structure (14), a rigid electrode structure (16), and a second deflectable membrane structure (18) in a vertically spaced configuration, wherein the rigid electrode structure (16) is disposed between the first deflectable membrane structure (14) and the second deflectable membrane structure (18), wherein the first deflectable membrane structure (14) and the second deflectable membrane structure (18) each include a deflectable portion (14-1, 18-1), and wherein the deflectable portion (14-1) of the first deflectable membrane structure (14) and the deflectable portion (18-1) of the second deflectable membrane structure (18) are mechanically coupled to each other by a mechanical connection element (20) and are mechanically decoupled from the rigid electrode structure (16); and A carrier element (22) for supporting the transducer element (12); And A plurality of clamping structures (24-1... 24-#) for mechanically connecting the transducer element (12) to the carrier element (22) along spaced-apart peripheral regions (26-1... 26-#) of the transducer element (12).

2. The MEMS device (10) according to claim 1, wherein the combined length of the clamping structures (24-1... 24-#) along the periphery of the transducer element (12) is equal to or less than 50% of the peripheral length (L) of the transducer element (12), and wherein a transverse bisector line (30) passing through each of the clamping regions (26-1... 26-#) passes through the geometric center region (28) of the transducer element (12).

3. The MEMS device (10) according to claim 1 or 2, wherein the clamping structures (24-1... 24-#) are equidistantly spaced along the periphery of the transducer element (12).

4. The MEMS device (10) according to any one of the preceding claims, wherein the plurality of clamping structures (24-1... 24-#) includes 2N clamping structures, where N = 1, 2, 3, 4..., and wherein the corresponding transverse bisector lines (30) pass through two opposite clamping regions (26-1... 26-#) and the geometric center region (28) of the transducer element (12).

5. The MEMS device (10) according to claim 1 or 2 or 3, wherein the plurality of clamping structures (24-1... 24-#) includes 2N+1 clamping structures, where N = 1, 2, 3, 4..., and wherein each transverse symmetry axis (30) of the transducer element (12) passes through the clamping structures and the geometric center region (28) of the transducer element (12).

6. The MEMS device (10) according to any one of the preceding claims, wherein the geometric center region (28) has a transverse extension around the geometric center (C) of the transducer element (12), and the transverse extension is less than 5% of the diameter of the transducer element (12).

7. The MEMS device (10) according to any one of the preceding claims, wherein the first deflectable membrane structure (14) and the second deflectable membrane structure (18) form a cavity (36) with respect to the environment, and the cavity (36) is sealed with respect to the environment.

8. The MEMS device (10) according to claim 7, wherein the clamping structures (24-1... 24-#) at the spaced-apart peripheral regions (26-1... 26-#) of the transducer element (12) and the wall elements (29-1... 29-#) at the unclamped, spaced-apart peripheral regions (27-1... 27-#) of the transducer element (12) form an annular wall structure (40) along the periphery of the transducer element (12), wherein the annular wall structure (40) laterally confines the cavity (36) with respect to the environment.

9. The MEMS device (10) according to claim 7 or 8, wherein the cavity (36) includes a low-pressure region, wherein the low-pressure region includes a reduced atmospheric pressure compared to the ambient atmosphere, and wherein, for example, the reduced atmospheric pressure in the low-pressure region is a vacuum or near-vacuum.

10. The MEMS device (10) according to claim 8 or 9, wherein at least one or all of the wall elements (29-1... 29-#) include corrugated wall sections (42-1... 42-#).

11. The MEMS device (10) according to claim 10, wherein the corrugated wall sections (42-1... 42-#) have a curved, circular, sinusoidal or semi-circular shape, for example a circular, oval or elliptical section shape, or wherein the corrugated wall sections have a square, rectangular, triangular or serrated shape.

12. The MEMS device (10) according to claim 10 or 11, wherein the corrugated wall sections (42-1... 42-#) extend into and / or protrude from the cavity.

13. The MEMS device (10) according to any one of the preceding claims, wherein the mechanical connection element (20) includes a plurality of columnar or cylindrical mechanical connection elements between the two opposing deflectable membrane structures (14, 18).

14. The MEMS device (10) according to claim 13, wherein the plurality of columnar or cylindrical mechanical connection elements (20) are non-conductive.

15. The MEMS device (10) according to any one of the preceding claims, wherein the rigid electrode structure (16) forms a counter electrode with respect to the first deflectable membrane structure (14) and the second deflectable membrane structure (18).

16. The MEMS device (10) according to any one of the preceding claims, wherein the transducer element has a microphone and / or speaker function.

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