Micromechanical component for an actuator and / or sensor device and manufacturing process for a micromechanical component of an actuator and / or sensor device

Abstract

The present invention provides a micromechanical component for an actuator and / or sensor device with a deformable membrane (28) and electrodes (26a, 26b) which, when the potential of the electrodes (26a, 26b) is equal, protrude along a first spatial direction (x) oriented perpendicular to a first membrane surface (28a) by a maximum electrode height and each have a maximum length in a second spatial direction (y) oriented parallel to the first membrane surface (28a) and a maximum width in a third spatial direction (z) oriented perpendicular to the second spatial direction (y) and parallel to the first membrane surface (28a), wherein the maximum length of each electrode (26a, 26b) is greater than the maximum electrode height and l is the maximum width of the same electrode (26a, 26b), and wherein at least a part of each of the electrodes (26a,26b) Etching traces of at least one etching process with an etching direction aligned parallel to the second spatial direction (y) and etched residual material comprising at least one electrically conductive electrode material layer (10a, 10b, 10c).

Description

[0001] The present invention relates to a micromechanical component for an actuator and / or sensor device. The invention also relates to an actuator and / or sensor device. Furthermore, the present invention relates to a manufacturing method for a micromechanical component of an actuator and / or sensor device. State of the art

[0002] From DE 10 2022 212 404 A1, a micromechanical component for a sound-generating and / or sound-amplifying device is known, comprising a deformable membrane structure and at least two electrodes in mechanical contact with the membrane structure. The electrodes have a minimum height along a first spatial direction perpendicular to a membrane surface of the membrane structure, which is at least three times greater than the membrane thickness of the membrane structure in the first spatial direction. Additionally, the electrodes have a maximum length in a second spatial direction parallel to the membrane surface and a maximum width in a third spatial direction perpendicular to the second spatial direction and parallel to the membrane surface, wherein the maximum length of each electrode is at least five times greater than the maximum width of the same electrode. Disclosure of the invention

[0003] The present invention provides a micromechanical component for an actuator and / or sensor device with the features of claim 1, an actuator and / or sensor device with the features of claim 6 and a manufacturing method for a micromechanical component of an actuator and / or sensor device with the features of claim 8. Advantages of the invention

[0004] The present invention provides advantageous possibilities for the manufacture of a micromechanical component with electrodes that can be described as "vertical lamellae," the main direction of expansion of which runs parallel to at least one membrane surface of the membrane to which they are fitted, and the secondary direction of expansion of which runs perpendicular to the respective membrane surface. The electrodes, which can be described as "vertical lamellae," enable the deflection / warping of the membrane fitted with them to be caused perpendicular to the main direction of expansion of the electrodes and / or the detection of the deflection / warping of the membrane perpendicular to the main direction of expansion. In both cases, the electrodes described as "vertical lamellae" constitute a drive and / or detection structure which, compared to the size / area of ​​the membrane fitted with them, exhibits good efficiency in causing and / or detecting the deflection / warping of the membrane.Using the present invention, micromechanical components equipped with such advantageous "vertical lamellae" can be manufactured, whereby, as a rule, only one substrate is required for the respective micromechanical component, electrical wiring of all electrodes designed as "vertical lamellae" is easily implemented, and small distances between adjacent electrodes are possible regardless of the electrode dimensions. As will also become clear from the following description, micromechanical components designed with "vertical lamellae" can be produced at comparatively low manufacturing costs using a manufacturing process according to the invention.

[0005] In an advantageous embodiment of the micromechanical component, the first membrane also exhibits etch marks from the at least one etching process with the etching direction aligned parallel to the second spatial direction, and the first membrane comprises etched residual material from at least one electrically conductive electrode material layer and a second electrically conductive electrode material layer. As will become clear from the description below, the design of the first membrane described here enables simple potential guidance when a non-zero potential difference is applied between the at least one first electrode and the at least one second electrode. In particular, few or no additional elements are required for potential guidance.

[0006] Preferably, the membrane comprises, as the etched residual material, at least a first residual material region from the first electrically conductive electrode material layer and at least a second residual material region from the second electrically conductive electrode material layer, wherein the at least one first residual material region is electrically insulated from the at least one second residual material region by means of an electrically insulating intermediate region, and wherein the at least one first electrode is electrically connected to the at least one first residual material region and the at least one second electrode is electrically connected to the at least one second residual material region. This enables a robust mechanical connection of the electrodes to the first membrane, which can nevertheless be designed as a "mechanically flexible" membrane. Simultaneously, a high integration density of the electrodes on the first membrane is possible.

[0007] In a further advantageous embodiment of the micromechanical component, the electrodes comprise a first group of outer electrodes, a second group of outer electrodes, a first group of inner electrodes, and a second group of inner electrodes, wherein the first group of outer electrodes are mechanically connected to a first partial surface of the first membrane surface, the second group of outer electrodes are mechanically connected to a second partial surface of the second membrane surface opposite the first partial surface, the first group of inner electrodes are mechanically connected to a third partial surface of the first membrane surface located between the first partial surface and a center of the first membrane surface, and the second group of inner electrodes are mechanically connected to a fourth partial surface of the second membrane surface opposite the third partial surface.and wherein the electrodes of the first group of outer electrodes, the second group of outer electrodes, the first group of inner electrodes, and the second group of inner electrodes are electrically contactable such that a first time-varying voltage signal can be applied simultaneously between the first and second electrodes of the first group of outer electrodes and the second group of inner electrodes, and a second time-varying voltage signal, differing from the first voltage signal, can be applied simultaneously between the first and second electrodes of the second group of outer electrodes and the first group of inner electrodes. The description below makes it clear that this achieves efficient use of space and control of the electrodes used as "vertical displacement and drive structures."

[0008] Alternatively or additionally, the micromechanical component can also comprise a deformable second membrane with a third membrane surface and a fourth membrane surface oriented away from the third membrane surface, wherein further electrodes are mechanically connected at least to the third membrane surface, wherein the second membrane is arranged relative to the first membrane such that the third membrane surface is oriented towards the second membrane surface equipped with electrodes, and wherein the respective electrodes are distributed on the second membrane surface and the third membrane surface such that first electrode contact surfaces, at which the second membrane surface is mechanically contacted by electrodes, and second electrode contact surfaces, at which the third membrane surface is mechanically contacted by electrodes, are definable.and when the second membrane surface is projected onto the third membrane surface, the first electrode contact surfaces of all electrodes of the second and third membrane surfaces do not overlap with the second electrode contact surfaces. By means of the "offset" of the electrodes on the second and third membrane surfaces described here, a closer positioning of the second membrane to the first membrane is possible without the risk of undesired electrode contact in the event of deflection / warping of at least one of the membranes.

[0009] The advantages described above are also realized in an actuator and / or sensor device with such a micromechanical component. The actuator and / or sensor device, designed as such, can in particular be a sound generation or sound amplification device. However, the examples of actuator and / or sensor devices listed here are not to be interpreted restrictively.

[0010] Furthermore, implementing a corresponding manufacturing process also yields the advantages described above. It is expressly noted that the manufacturing process can be further developed according to the described embodiments of the micromechanical component and / or the actuator and / or sensor device. Brief description of the drawings

[0011] Further features and advantages of the present invention are explained below with reference to the figures. They show: Fig. 1A to 1C schematic top views and cross-sections of intermediate products to illustrate a first embodiment of the manufacturing process; Fig. 2a to 2d schematic cross-sections of finished products to illustrate a second embodiment of the manufacturing process; and Fig. 3 to 11 schematic representations of different embodiments of the micromechanical component. Embodiments of the invention

[0012] Fig. Figures 1A to 1C show schematic top views and cross-sections of intermediate products to illustrate a first embodiment of the manufacturing process.

[0013] The manufacturing process described below produces a micromechanical component that can be used, for example, in an actuator and / or sensor device. The micromechanical component is formed with at least one membrane and electrodes mechanically connected to a first membrane surface and / or to a second membrane surface facing away from the first. The electrodes comprise at least one first electrode and at least one second electrode, which are mechanically connected to the membrane in such a way that a non-zero potential difference can be applied between the at least one first electrode and the at least one second electrode.

[0014] The mechanical attachment of the electrodes to the first membrane surface and / or the second membrane surface is such that, when the potential of the electrodes is equal (i.e., when there is no non-zero potential difference between at least some of the electrodes), the electrodes protrude along a spatial direction x perpendicular to the first membrane surface by a so-called maximum electrode height on the first membrane surface and / or on the second membrane surface.

[0015] Furthermore, when the electrodes are at the same potential, they each have a maximum length in a spatial direction y parallel to the first membrane surface and a maximum width in a spatial direction z perpendicular to y and parallel to the first membrane surface. The maximum length of each electrode is at least 5 times greater than the maximum width of the same electrode. Additionally, the maximum height of each electrode is at least 1.5 times greater than the maximum width of the same electrode. Therefore, the maximum length of each electrode can also be described as its principal direction of extension.

[0016] As will become clear from the following description, the electrodes with the dimensions described in the preceding paragraph can be formed relatively easily by etching at least a portion of each electrode out of at least one electrically conductive electrode material layer / functional layer 10a and 10b using at least one etching process. A relatively simple potential guide for applying the non-zero potential difference between the at least one first electrode and the at least one second electrode is provided in the embodiment of the Fig. 1A to 1C enables this by etching out, in addition to at least part of each of the electrodes, the membrane from at least one first electrically conductive electrode material layer / functional layer 10a and a second electrically conductive electrode material layer / functional layer 10b (as the at least one electrically conductive electrode material layer 10a and 10b) by means of at least one etching process.

[0017] As an example, in the manufacturing process described here, the first electrode material layer 10a is first formed on a structured first sacrificial layer 12, which at least partially covers a substrate 14. The substrate 14 can be, for example, a semiconductor substrate, such as a silicon substrate. The first sacrificial layer 12 is preferably an oxide layer whose thickness in the spatial direction y can be less than or equal to 2 µm. Preferably, the first electrically conductive electrode material layer 10a is a polysilicon layer whose thickness in the spatial direction y can be less than or equal to 10 µm.

[0018] To ensure simple potential flow, the at least one subsequent first electrode is electrically connected to at least one first residual material region 16a, which is formed from the first electrically conductive electrode material layer 10a, while the at least one subsequent second electrode is electrically insulated from the at least one first residual material region 16a. This is shown in the Fig. 1Aa to 1Ac clarifies by the Fig. 1Ab a cross-section along line AA' of the Fig. 1Aa, which passes through a later first electrode, and the Fig. 1Ac a cross-section along line BB' of the Fig. 1Aa, which passes through a subsequent second electrode. As in Fig. As can be seen from 1Ac, the electrical insulation of the at least one subsequent second electrode from the at least one first residual material region 16a can be ensured by means of at least one etching groove 18 etched through the first electrically conductive electrode material layer 10a in the spatial direction y. Partial outer surfaces of the at least one subsequent first electrode and the at least one subsequent second electrode can also be structured from the first electrically conductive electrode material layer 10a by means of the at least one etching groove 18. Partial surfaces of the subsequent first membrane surface and the subsequent second membrane surface can also be structured from the first electrically conductive electrode material layer 10a by means of the at least one etching groove 18. The extent of the at least one etching groove 18 in the spatial direction x is preferably less than or equal to 2 µm. The intermediate product obtained in this way is in the Fig. 1Aa to 1Ac are represented graphically.

[0019] Subsequently, a second sacrificial layer 20 is deposited and structured. The at least one etching groove 18 can also be filled with the second sacrificial layer 20. Preferably, the second sacrificial layer 20 is an oxide layer. A layer thickness of less than or equal to 2 µm in the spatial direction y is preferred for the second sacrificial layer 20. The second sacrificial layer 20 is structured such that the first electrically conductive electrode material layer 10a is exposed in the region of the at least one subsequent first electrode and the at least one subsequent second electrode. Furthermore, in the manufacturing process described here, the at least one first residual material region 16a is electrically insulated from at least one second residual material region 16b, which is formed from the at least one subsequently deposited electrically conductive electrode material layer 10b, by means of at least one electrically insulating intermediate region 22.For this purpose, the second sacrificial layer 20 is also removed in the region of the at least one subsequently formed electrically insulating intermediate region 22. Subsequently, the at least one material of the at least one electrically insulating intermediate region 22, preferably silicon-rich silicon nitride, is deposited and structured. Only then is the second electrically conductive electrode material layer 10b deposited. Preferably, the second electrically conductive electrode material layer 10b is a polysilicon layer, in particular with a layer thickness in the spatial direction y of less than or equal to 10 µm. The intermediate product is removed by means of the . Fig. 1 Ba (cross-section along line AA') and 1 Bb (cross-section along line BB') are shown.

[0020] In the manufacturing process described here, the at least one subsequent second electrode is electrically connected to the at least one second residual material region 16b, while the at least one subsequent first electrode is electrically insulated from the at least one second residual material region 16b. For electrical insulation of the at least one subsequent first electrode, at least one etching groove 24 is etched through the second electrically conductive electrode material layer 10b. Advantageously, partial outer surfaces of the at least one subsequent first electrode and the at least one subsequent second electrode can also be structured from the second electrically conductive electrode material layer 10b by means of the at least one etching groove 24.Accordingly, partial areas of the subsequent first membrane surface and the subsequent second membrane surface can also be structured from the second electrically conductive electrode material layer 10b by means of the at least one etching trench 24. The at least one etching trench 24 preferably has a trench width of less than or equal to 2 µm in the spatial direction x. The at least one etching trench 24 can be filled by depositing and structuring a further sacrificial layer (not shown). The at least one further sacrificial layer, preferably an oxide layer, can have a layer thickness of less than or equal to 2 µm in the spatial direction y.

[0021] Fig. 1 Ca (cross-section along line AA') and Fig. Figure 1 Cb (cross-section along line BB') shows the intermediate or final product after an isotropic sacrificial layer etching process for the exposure of the at least one first electrode 26a and the at least one second electrode 26b. The isotropic sacrificial layer etching process is preferably carried out as an RF process in the gas phase.

[0022] As shown by the Fig. As becomes clear from the figures 1 Ca and 1 Cb, in the manufacturing process described here for etching out at least the electrodes 26a and 26b and possibly also the membrane 28 with its first membrane surface 28a and its second membrane surface 28b from at least the electrically conductive electrode material layers 10a and 10b, the previously described etching processes are each carried out with an etching direction aligned parallel to the spatial direction y. Thus, the etching out of the electrodes 26a and 26b from the at least one electrically conductive electrode material layer 10a and 10b does not occur perpendicular to the first membrane surface 28a or the second membrane surface 28b of the membrane 28, but parallel to the membrane surfaces 28a and 28b of the membrane 28 in the spatial direction y in which the electrodes 26a and 26b have their main direction of extension.The manufacturing process described here is therefore not only comparatively easy to implement, but also allows for considerable design freedom in the shape of the electrodes 26a and 26b. At the same time, this high degree of design freedom in the shape of the electrodes 26a and 26b does not preclude an equally simple electrical connection of the electrodes 26a and 26b. It should also be noted that each electrode 26a or 26b has the same electrical potential across its entire area, while at the same time different electrical potentials can be introduced into the electrode material layers 10a and 10b.

[0023] Fig. Figures 2a to 2d show schematic cross-sections of end products to illustrate a second embodiment of the manufacturing process.

[0024] As a further development of the previously described embodiment of Fig. 1A to 1C are used in the manufacturing process of the Fig. In steps 2a to 2d, the electrodes 26a and 26b and the membrane 28 are structured from a layer stack by means of at least one etching step with the etching direction aligned parallel to the spatial direction y. This stack comprises, in addition to the first electrically conductive electrode material layer 10a and the second electrically conductive electrode material layer 10b, a third electrically conductive electrode material layer / functional layer 10c. For this purpose, the third electrically conductive electrode material layer 10c, preferably a polysilicon layer with a layer thickness in the spatial direction y of less than or equal to 10 µm, is deposited and structured before the deposition and structuring of the second electrically conductive electrode material layer 10b. Preferably, only etch grooves 30 with a groove width of less than or equal to 2 µm are formed for structuring the third electrically conductive electrode material layer 10c.By means of the at least one etching groove 30, at least one third residual material region 16c of the membrane 28 can be structured out of the third electrically conductive electrode material layer 10c. To ensure electrical insulation of the at least one third residual material region 16c from both the at least one first residual material region 16a and the at least one second residual material region 16b, at least one further electrically insulating intermediate region 32, preferably made of silicon-rich silicon nitride, can be formed in addition to the at least one electrically insulating intermediate region 22. The same subprocesses as for forming the at least one electrically insulating intermediate region 22 can be repeated to form the at least one further electrically insulating intermediate region 32.

[0025] During the cross-section of the Fig. 2a only passes through the membrane 28, the cross-sections of the Fig. 2b a first electrode 26a, the Fig. 2d a second electrode 26b and the Fig. 2c, a component 34 anchored to the membrane 28 in addition to the electrodes 26a and 26b, which is electrically insulated from both all first electrodes 26a and all second electrodes 26b. Each first electrode 26a is electrically connected to at least one first residual material region 16a of the membrane 28 via an electrically conductive contact 36a, which may in particular be formed from material of the third electrically conductive electrode material layer 10c. Similarly, an electrically conductive contact 36b, e.g., made of material of the at least one third electrically conductive electrode material layer 10c, is also present between each second electrode 26b and the at least one second residual material region 16b.

[0026] As an optional further training, the micromechanical component of the Fig. 2a to 2d, a capping 38 is provided, which is preferably formed as a doped polysilicon layer. The isotropic sacrificial layer etching process already mentioned above can be carried out via at least one etching access 38a extending through the capping 38. Optionally, at least one metallic contact area 40 can be formed on the capping 38.

[0027] Regarding further processes of the manufacturing process of the Fig. 2a to 2d and their advantages refer to the description of the embodiment of the Fig. Refer to 1A to 1C.

[0028] Furthermore, with regard to other characteristics and properties of the products manufactured using the production methods of the Fig. 1 and Fig. Reference is made to the description of the following embodiments for the 2 manufactured micromechanical components and their advantages.

[0029] Fig. Figure 3 shows a schematic representation of a first embodiment of the micromechanical component.

[0030] The in Fig. Figure 3 schematically depicts a micromechanical component that has at least one deformable first membrane 28 with a first membrane surface 28a and a second membrane surface 28b oriented away from the first membrane surface 28a. The micromechanical component also has electrodes 26a and 26b, which are mechanically connected to the first membrane surface 28a and / or the second membrane surface 28b, respectively. The electrodes 26a and 26b comprise at least one first electrode 26a and at least one second electrode 26b, each of which can be mechanically contacted such that a non-zero potential difference can be applied between the at least one first electrode 26a and the at least one second electrode 26b. Preferably, a second electrode 26b is arranged between each pair of first electrodes 26a and / or a first electrode 26a is arranged between each pair of second electrodes 26b.

[0031] When electrodes 26a and 26b have the same potential (i.e., when there is no non-zero potential difference between at least some of the electrodes 26a and 26b), the electrodes 26a and 26b protrude along a spatial direction x perpendicular to the first membrane surface 28a at the first membrane surface 28a and / or at the second membrane surface 28b. Additionally, when electrodes 26a and 26b have the same potential, each electrode 26a and 26b has a maximum length in a spatial direction y parallel to the first membrane surface 28a and a maximum width in a spatial direction z perpendicular to the spatial direction y and parallel to the first membrane surface 28a, where the length of each electrode 26a and 26b is greater than the width of the same electrode 26a and 26b by at least a factor of 5.Furthermore, the maximum electrode height of each electrode 26a and 26b is at least 1.5 times greater than the maximum width of the same electrode 26a and 26b. The maximum length of each electrode 26a and 26b can therefore also be described as its principal direction of extension.

[0032] The micromechanical component of the Fig. 3 is produced by carrying out the manufacturing process described above. Therefore, at least a portion of each of the electrodes 26a and 26b exhibits etch marks from at least one etching process with an etch direction oriented parallel to the spatial direction y. Accordingly, at least the portion of each of the electrodes 26a and 26b comprises etched residual material of at least one electrically conductive electrode material layer 10a to 10c. The first membrane 28 can also exhibit etch marks from the at least one etching process with the etch direction oriented parallel to the second spatial direction and comprise etched residual material of at least one electrically conductive electrode material layer 10a and a second electrically conductive electrode material layer 10b (as the at least one electrically conductive electrode material layer 10a to 10c). Although this in Fig. 3. Not shown in the illustration, the first membrane 28, as the etched residual material, can have at least one first residual material region 16a from the first electrically conductive electrode material layer 10a and at least one second residual material region 16b from the second electrically conductive electrode material layer, wherein the at least one first residual material region 16a is electrically insulated from the at least one second residual material region 16b by means of an electrically insulating intermediate region 22. As explained above, the at least one first electrode 26a can optionally be electrically connected to the at least one first residual material region 16a and the at least one second electrode 26b can optionally be electrically connected to the at least one second residual material region 16b.This facilitates electrical contact between electrodes 26a and 26b to establish a non-zero potential difference between the at least one first electrode 26a and the at least one second electrode 26b.

[0033] As an optional further training, the micromechanical component of the Fig. 3. A second, deformable membrane 42 with a third membrane surface 42a and a fourth membrane surface 42b oriented away from the third membrane surface 42a. Further electrodes 44 are mechanically connected at least to the third membrane surface 42a. The second membrane 42 and its electrodes 44 can also be produced by carrying out the manufacturing process described above. The second membrane 42 and its electrodes 44 can optionally have the same features and properties as the first membrane 28 and its electrodes 26a and 26b.

[0034] Furthermore, the second membrane 42 is arranged relative to the first membrane 28 such that the third membrane surface 42a, equipped with electrodes 44, is aligned with the second membrane surface 28b, equipped with electrodes 26a and 26b. The membranes 28 and 42 can be described as "vertical membranes." Optionally, the membranes 28 and 42 can be anchored at their edges in a chip frame 46 as so-called clamped-clamped structures. Configuring the membranes 28 and 42 as clamped-clamped structures has the advantage that, due to the firm anchoring of the membranes 28 and 42 to the chip frame 46, no acoustic leakage path can occur at this point, which would be associated with a power loss. Alternatively, the membranes 28 and 42 can also be anchored to a wafer as free-free structures at at least one of their membrane surfaces 28a, 28b, 42a, and 42b.

[0035] As shown by the Fig. As can be seen in Figure 3, both membranes 28 and 42 can be set into oscillatory / warping movements together by means of a time-varying voltage signal applied between the first electrodes 26a and 44 and the second electrodes 26b and 44 of the electrodes 26a, 26b and 44. In this way, a comparatively large volume of a medium adjacent to at least one of the membrane surfaces 28a, 28b, 42a and 42b, especially near the center of the respective membrane surface 28a, 28b, 42a and 42b, can be displaced. (Near the chip frame 46, however, the displaced volume is relatively limited.) Due to the design of the membranes 28 and 42 as clamped-clamped structures (and since none of the countermeasures described below are used), the deflection of both membranes 28 and 42 is sinusoidal.Due to the sinusoidal displacement of each membrane 28 and 42, there is a non-linear relationship between the respective displacement of membranes 28 and 42 and the displaced volume. An exponentially higher displacement would result in a larger displaced volume, but would also require an exponentially higher force.

[0036] Fig. Figure 4 shows a schematic representation of a second embodiment of the micromechanical component.

[0037] In addition to the embodiment described above, Fig. 3 is in the micromechanical component of the Fig. 4. At least one membrane stiffening structure 34 is formed on each of the at least one membrane 28 and 42. Regarding an advantageous way of producing the at least one membrane stiffening structure 34, reference is made to the description of the manufacturing process of the Fig. Reference is made to 2a to 2d. For example, the at least one membrane stiffening structure 34 can be a so-called "piston area", particularly at the center of the respective membranes 28 and 42. By means of the at least one membrane stiffening structure 34, the shape of the at least one deflected / curved membrane 28 and 42 can be modified such that a comparatively large central surface of the respective membrane 28 or 42 remains aligned parallel to the spatial directions y and z. In this way, an increased volume can be displaced in relation to the resulting deflection / curvature. As shown by the Fig. As is also evident in Figure 4, the at least one membrane stiffening structure 34 enables a comparatively close positioning of adjacent membranes 28 and 42, without any mechanical contact occurring between the membranes 28 and 42, in particular not between their electrodes 26a, 26b and 44, when they are deflected / curved.

[0038] Regarding further features and properties of the micromechanical component of the Fig. 4 and its advantages will be described in the description of the embodiment of the Fig. 3 referred.

[0039] Fig. Figure 5 shows a schematic representation of a third embodiment of the micromechanical component.

[0040] The micromechanical component of the Fig. 5 indicates as a supplement to the embodiment of the Fig. 3 a first group 48e-1 of outer / external electrodes 26a and 26b on the second membrane surface 28b, a first group 48i-1 of inner electrodes 26a and 26b on the first membrane surface 28a, a second group 48e-2 of outer / external electrodes 44 on the third membrane surface 42a and a second group 48i-2 of inner electrodes 44 on the fourth membrane surface 42b.Additionally, the respective groups 48i-1 and 48i-2 of inner electrodes 26a, 26b and 44 are positioned relative to the groups 48e-1 or 48e-2 of outer electrodes 26a, 26b and 44 of the same membrane 28 or 42 such that, while the respective groups 48e-1 or 48e-2 of outer electrodes 26a, 26b and 44 are located on an outer / external partial surface 28b-e or 42a-e of the second or third membrane surface 28b or 42a, the groups 48i-1 and 48i-2 of inner electrodes 26a, 26b and 44 of the same membrane 28 or 42 are located between a counter-partial surface 28a-e or 42b-e of the first or fourth membrane surface 28a or 42, opposite the outer partial surface 28b-e or 42a-e. 42b and a center of the first or fourth membrane surface 28a or 42b.

[0041] The electrodes 26a, 26b and 44 of each group 48e-1, 48e-2, 48i-1 and 48i-2 of outer or inner electrodes 26a, 26b and 44 are electrically contactable in such a way that a time-varying voltage signal can be applied simultaneously between the first electrodes 26a and 44 and the second electrodes 26b and 44 of the respective group 48e-1, 48e-2, 48i-1 and 48i-2 of outer or inner electrodes 26a, 26b and 44. By simultaneously operating the respective groups 48e-1, 48e-2, 48i-1 and 48i-2 of the outer and inner electrodes 26a, 26b and 44 of the respective membrane 28 or 42, the respective membrane 28 or 42 is deflected and simultaneously "bent back", thereby causing a (essentially) parallel alignment of the respective central surface of the deflected / curved membrane 28 or 42 parallel to the spatial directions y and z.Groups 48e-1 and 48e-2 of outer electrodes 26a, 26b, and 44 are thus responsible for deflecting the respective membranes 28 and 42, while groups 48i-1 and 48i-2 of inner electrodes 26a, 26b, and 44 cause a so-called "reflexion" of the central region of the respective membrane 28 or 42. The formation of at least one membrane stiffening 34 is therefore unnecessary. Consequently, less force is required to deflect / curve the respective membrane 28 or 42. Furthermore, groups 48i-1 and 48i-2 of inner electrodes 26a, 26b, and 44 provide more force for deflecting / curving the respective membrane 28 or 42, as they can be used as "additional" active elements. If desired, the groups 48e-1, 48e-2, 48i-1 and 48i-2 of outer and inner electrodes 26a, 26b and 44 can also be designed in the form of spring elements, which additionally increases the extensibility of the respective membrane 28 or 42.In this way, the restoring force of the respective membrane 28 or 42 can be reduced due to the stretching caused by its deflection / warping.

[0042] Regarding further features and properties of the micromechanical component of the Fig. 5 and its advantages will be described in the description of the embodiment of the Fig. 3 referred.

[0043] Fig. 6a and Fig. Figure 6b shows schematic representations of a fourth embodiment of the micromechanical component.

[0044] As shown by the Fig. 6a and Fig. As can be seen in Figure 6b, even in a micromechanical component with only one membrane, 28 groups 48e-1 and 48i-1 of outer and inner electrodes 26a and 26b can be attached to the membrane surfaces 28a and 28b of the respective membrane 28. The respective membrane 28 can, for example, be moved towards and / or away from a fixed wall 50 or a fixed component.

[0045] Regarding further features and properties of the micromechanical component of the Fig. 6a and Fig. 6b and its advantages will be described in the description of the embodiments of the Fig. 3 and Fig. 5 referred.

[0046] Fig. Figure 7 shows a schematic representation of a fifth embodiment of the micromechanical component.

[0047] The in Fig. Figure 7 schematically depicts a micromechanical component comprising several identical membrane-electrode systems, each with a membrane 28 equipped with a first group 48e-1 of outer electrodes 26a and 26b and a second group 48e-2 of outer electrodes 26a and 26b. The first group 48e-1 of outer electrodes 26a and 26b is mechanically connected to a first partial surface 28a-e of the first membrane surface 28a. In contrast, the second group 48e-2 of outer electrodes 26a and 26b is mechanically connected to a second partial surface 28b-e of the second membrane surface 28b, opposite the first partial surface 28a-e. Potentials other than zero can be applied alternately between the first and second electrodes 26a and 26b of the first group 48e-1 from external electrodes 26a and 26b or between the first and second electrodes 26a and 26b of the second group 48e-2 from external electrodes 26a and 26b.

[0048] Preferably, the distance between two adjacent membrane-electrode systems is large enough that even in the deflected / bulged state of the membranes 28, no mechanical contact can occur between the adjacent membrane-electrode systems. It can be seen that the minimum possible distance without mechanical contact between two adjacent membrane-electrode systems depends on the maximum deflection / bulging of the membranes 28 and the electrode height of the electrodes 26a and 26b on the opposing membrane surfaces 20a and 28b.

[0049] Regarding further features and properties of the micromechanical component of the Fig. 7 and their advantages will be described in the description of the embodiments of the Fig. 3, Fig. 5 and Fig. 6 referred.

[0050] Fig. Figure 8 shows a schematic representation of a sixth embodiment of the micromechanical component.

[0051] The micromechanical component of Fig. 8 demonstrate its membrane electrode systems as a complement to the previously described embodiment of the Fig. 7. A first group 48m-1 of central electrodes 26a and 26b is located on the first membrane surface 28a, and a second group 48m-2 of central electrodes 26a and 26b is located on the second membrane surface 28b. Preferably, the first group 48m-1 of central electrodes 26a and 26b and the second group 48m-2 of central electrodes 26a and 26b are positioned on the respective membrane 28 such that a center point of the respective membrane 28 coincides with a center point of the first group 48m-1 of central electrodes 26a and 26b and of the second group 48m-2 of central electrodes 26a and 26b. To effect an advantageously large deflection / curvature of the respective membrane 28, it is advantageous if the electrodes 26a and 26b of the first group 48e-1 are separated from external electrodes 26a and 26b, and those of the second group 48e-2 from external electrodes 26a and 26b,The first group 48m-1 of central electrodes 26a and 26b and the second group 48m-2 of central electrodes 26a and 26b are electrically contactable / are contacted in such a way that a first time-varying voltage signal can be applied / is applied simultaneously between the first electrodes 26a and the second electrodes 26b of the first group 48e-1 of outer electrodes 26a and 26b and the second group 48m-2 of central electrodes 26a and 26b, and a second time-varying voltage signal, different from the first voltage signal, can be applied / is applied simultaneously between the first electrodes 26a and the second electrodes 26b of the second group 48e-2 of outer electrodes 26a and 26b and the first group 48m-1 of central electrodes 26a and 26b.

[0052] Regarding further features and properties of the micromechanical component of the Fig. 8 and their advantages will be described in the description of the embodiments of the Fig. 3 and 5 to 7 referred.

[0053] Fig. Figure 9 shows a schematic representation of a seventh embodiment of the micromechanical component.

[0054] In addition to the embodiment of the Fig. 7 has each membrane electrode system of the micromechanical component of the Fig. 9 additionally a first group 48i-1 of inner electrodes 26a and 26b and a second group 48i-2 of inner electrodes 26a and 26b, wherein the first group 48i-1 of inner electrodes 26a and 26b is mechanically connected to a third sub-surface 28a-i of the first membrane surface 28a located between the first sub-surface 28a-e and a center of the first membrane surface 28a, and the second group 48i-2 of inner electrodes 26a and 26b is mechanically connected to a fourth sub-surface 28b-i of the second membrane surface 28b opposite the third sub-surface 28a-i.Preferably, the electrodes 26a and 26b of the first group 48e-1 are electrically contactable / connected to outer electrodes 26a and 26b, the electrodes of the second group 48e-2 are electrically contactable to outer electrodes 26a and 26b, the electrodes of the first group 48i-1 are electrically contactable to inner electrodes 26a and 26b, and the electrodes of the second group 48i-2 are electrically contactable / connected to inner electrodes 26a and 26b such that a first time-varying voltage signal can be applied simultaneously between the first electrodes 26a and the second electrodes 26b of the first group 48e-1 of outer electrodes 26a and 26b ... such that a first time-varying voltage signal can be applied simultaneously between the first electrodes 26a and the second electrodes 26b of the second group 48e-2 of outer electrodes 26a and 26b and the The first group 48i-1 can be / is applied to internal electrodes 26a and 26b.The mode of the micromechanical component achieved in this way can also be described as a "hammer mode" (or "piston mode").

[0055] By means of the micromechanical component of the Fig. The overall electrode structure of 9 enables a very efficient deflection / curvature of the membrane(s) 28. Even with a relatively close arrangement of adjacent membranes 28 to each other, there is little to no risk of mechanical contact between the membranes 28 or their electrodes 26a and 26b, since the groups 48i-1 and 48i-2 of inner electrodes 26a and 26b cause the advantageous "backward bending" of the central region of the respective membrane 28 already explained above. As can be seen from the Fig. As can be seen in 9, a comparatively close positioning of adjacent membranes 28 is therefore possible.

[0056] The "re-bending" of the central region of the respective membrane 28 can be achieved, in particular, by ensuring that the geometry of the deflected membrane 28 more closely resembles a "right-angled deflection" than a sinusoidal deflection, specifically by maintaining a comparatively large central area of ​​the deflected membrane 28 parallel to the spatial directions y and z. Simultaneously, the interaction of the groups 48e-1, 48e-2, 48i-1, and 48i-2 of the outer and inner electrodes 26a and 26b described here provides a sufficiently high force even to induce large deflection and warping movements of the respective membrane 28. The force generated by the various groups 48e-1, 48e-2, 48i-1, and 48i-2 of the inner and outer electrodes 26a and 26b is particularly well-suited for generating sound pressure or sound waves.Additionally, a relatively high volume of the medium adjacent to at least one of the membrane surfaces 28a and 28b can be displaced using the “hammer mode” (or “piston mode”).

[0057] Regarding further features and properties of the micromechanical component of the Fig. 9 and their advantages will be described in the description of the embodiments of the Fig. 3 and 5 to 7 referred.

[0058] Fig. Figure 10 shows a schematic representation of an eighth embodiment of the micromechanical component.

[0059] In contrast to the previously described micromechanical component of the Fig. 9 are in the embodiment of the Fig. 10 the respective electrodes 26a, 26b and 44 on the membrane surfaces 28a, 28b, 42a and 42b of the two adjacent membranes 28 and 42, in particular on the second membrane surface 26b and the third membrane surface 42a, are distributed such that first electrode contact surfaces 52-1, on which the second membrane surface 28b is mechanically contacted by electrodes 26a and 26b, and second electrode contact surfaces 52-2, on which the third membrane surface 42a is mechanically contacted by electrodes 44, are definable, wherein, when the second membrane surface 28b is projected onto the third membrane surface 42a, the first electrode contact surfaces 52-1 do not overlap with the second electrode contact surfaces 52-2 for all electrodes 26a, 26b and 44 of the second membrane surface 26b and the third membrane surface 42a.In this case, one can also speak of a (lateral) offset of electrodes 26a and 26b on the second membrane surface 28b relative to electrodes 44 on the third membrane surface 42a. The (lateral) offset of electrodes 26a, 26b, and 44 can also be described as an alternative positioning of these electrodes. Due to this (lateral) offset, the two adjacent membranes 28 and 42 can be placed significantly closer together without the risk of undesirable mechanical contact between their electrodes 26a, 26b, and 44 in the event of deflection or warping of membranes 28 and 42. Thus, the (lateral) offset eliminates a conventional limitation in the arrangement of membranes 28 and 42 relative to each other. Advantageously, the (lateral) offset also has no influence on the volume displaced by the deflection / curvature of membranes 28 and 42.

[0060] Regarding further features and properties of the micromechanical component of the Fig. 10 and their advantages will be described in the description of the embodiments of the Fig. 3 and 5 to 9 referred.

[0061] Fig. Figure 11 shows a schematic representation of a ninth embodiment of the micromechanical component.

[0062] The in Fig. The 11 schematically depicted micromechanical component represents a further development of the embodiment of the Fig. 10. Protrusions 54 are also found on the adjacent membranes 28 and 42. The protrusions 54 of membranes 28 and 42 are positioned such that, when the second membrane surface 28b is projected onto the third membrane surface 42a, the first electrode contact surfaces 52-1 of all electrodes 26a, 26b, and 44 of the second membrane surface 26b and the third membrane surface 42a are covered by the protrusions 54 formed on membrane 42, while the second electrode contact surfaces 52-2 are covered by the protrusions 54 formed on membrane 28. Thus, mechanical contact between the electrodes 26a, 26b, and 44 can be reliably prevented by means of the protrusions 54.

[0063] The depth of the protrusions 54 is freely selectable by design. For example, the protrusions 54 can have a depth greater than the maximum electrode height of the associated electrodes 26a, 26b, and 44. Furthermore, the protrusions can be used to modify the membrane properties of the respective membranes 28 or 42, particularly their stiffness. Specifically, the protrusions can be designed as spring elements. Alternatively, the protrusions can also be used to increase the electrode height of electrodes 26a, 26b, and 44, which can be used to increase the displaceable volume while maintaining the respective surface areas of the membranes 28 and 42.

[0064] Regarding further features and properties of the micromechanical component of the Fig. 11 and their advantages will be described in the description of the embodiments of the Fig. 3 and 5 to 10 referred.

[0065] For all the micromechanical components described above, the maximum electrode height of electrodes 26a and 26b in the spatial direction x can be between 100 µm (micrometers) and 1000 µm (micrometers). The maximum length of each electrode 26a and 26b in the spatial direction y is preferably between 1 mm (millimeters) and 10 mm (millimeters). For the maximum width of electrodes 26a and 26b in the spatial direction z, values ​​between 5 µm (micrometers) and 50 µm (micrometers) are preferred. An electrode spacing between two adjacent electrodes 26a and 26b is advantageously in the range between 0.5 µm (micrometers) and 10 µm (micrometers). This ensures a sufficiently high attractive force between adjacent electrodes 26a and 26b that are at different potentials.

[0066] The micromechanical components described above all feature a compact design.

[0067] All the micromechanical components described above can be part of an actuator and / or sensor device. In particular, these components can be part of a sound generation or sound amplification device, such as a microphone, a micro loudspeaker, a microspeaker / MEMS speaker, and / or a TWS (True Wireless Speaker). In all the examples listed here, achieving a sufficiently high SPL (Sound Pressure Level) is ensured, as is high sound power combined with high energy efficiency. The micromechanical components described above can also be used as ultrasonic transducers. Alternatively, they can also be part of a microfluidic device, such as a pump. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

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