Micromechanical components for sensor devices or microphone devices

Abstract

The present invention relates to a micromechanical component for a sensor device or a microphone device, comprising: a substrate; a frame structure, which is arranged on the substrate surface and / or at least one intermediate layer; a diaphragm, which spans an internal volume at least partially surrounded by the frame structure, wherein the internal volume is sealed in an airtight manner so that the diaphragm can be warped by means of a pressure difference between an internal pressure (p1) existing on its diaphragm inner side and an external pressure (p2) existing on its diaphragm outer side, wherein the micromechanical component has a bending beam structure arranged in the internal volume, the bending beam structure having at least one anchoring area fixed to the frame structure, the substrate surface and / or at least one intermediate layer and having at least one self-supporting area, which is connected to the diaphragm inner side of the diaphragm by at least one coupling structure in such a way that the at least one self-supporting area can be bent by means of the warping of the diaphragm.

Description

Technical Field

[0001] The present invention relates to a micromechanical component for a sensor device or a microphone device and also to a method for producing a micromechanical component for a sensor device or a microphone device. Background Art

[0002] Figure 1 A schematic diagram of a conventional pressure sensor device is shown, which is known to the applicant as internal prior art.

[0003] exist Figure 1 The pressure sensor device schematically shown in FIG. 1 comprises a substrate 10 having a substrate surface 10a; a frame structure 14 arranged on at least one intermediate layer 12a and 12b that at least partially covers substrate surface 10a; and a diaphragm 16. Diaphragm 16 spans an interior volume 18 at least partially surrounded by frame structure 14 in such a way that a diaphragm inner side 16a of diaphragm 16 adjoins interior volume 18. Diaphragm 16 can also be warped by a pressure difference between an internal pressure p1 on its diaphragm inner side 16a and an external pressure p2 on its diaphragm outer side 16b that is oriented away from diaphragm inner side 16a. As in Figure 1 As schematically shown in FIG, the pressure F acting on the diaphragm due to the pressure difference between the internal pressure p1 and the external pressure p2 can deform the diaphragm to such an extent that cracks 20 are generated in the diaphragm 16, in particular in the clamping area (Einspannungsbereich) 16c of the diaphragm 16.

[0004] For example, Figure 1 The conventional pressure sensor device further comprises a measuring electrode 22 which is suspended on the inner side 16a of the diaphragm 16 via at least one suspension structure 24. Between the measuring electrode 22 and the substrate surface 10a, a measuring counter electrode 26 is fixed to at least one intermediate layer 12a and 12b. Figure 1 The conventional pressure sensor device also includes at least one fixed reference electrode 28, which is at a predetermined distance from at least one reference counter electrode 30 fixed on at least one intermediate layer 12a and 12b, wherein the at least one reference electrode 28 and the at least one reference counter electrode 30 are at least partially arranged circumferentially around the measuring electrode 22 and the measuring counter electrode 26. Summary of the Invention

[0005] The present invention provides a micromechanical component for a sensor device or a microphone device, the micromechanical component comprising:

[0006] a substrate having a substrate surface;

[0007] a frame structure arranged on the substrate surface and / or at least one intermediate layer at least partially covering the substrate surface; and

[0008] a diaphragm that spans an interior volume at least partially surrounded by the frame structure such that an inner side of the diaphragm abuts the interior volume;

[0009] The inner volume is sealed in a gas-tight manner such that the diaphragm can be warped by the pressure difference between the internal pressure prevailing on its diaphragm inner side and the external pressure prevailing on the diaphragm outer side directed away from the diaphragm inner side,

[0010] It is characterized by

[0011] A curved beam structure is arranged in the internal volume, the curved beam structure having at least one anchoring area fixed to a frame structure, a substrate surface and / or at least one intermediate layer and having at least one self-supporting area, which is connected to the inner side of the diaphragm via at least one coupling structure in such a way that the at least one self-supporting area can be bent by means of the warping of the diaphragm.

[0012] The present invention further provides a method for producing a micromechanical component for a sensor device or a microphone device, the method comprising the following steps:

[0013] forming a frame structure on a substrate surface of the substrate and / or on at least one intermediate layer at least partially covering the substrate surface; and

[0014] spanning an interior volume at least partially surrounded by the frame structure by means of a membrane such that the membrane inner side of the membrane adjoins the interior volume;

[0015] The inner volume is sealed in a gas-tight manner such that the diaphragm can be warped by the pressure difference between the internal pressure prevailing on its diaphragm inner side and the external pressure prevailing on the diaphragm outer side directed away from the diaphragm inner side,

[0016] It is characterized by the following steps:

[0017] A curved beam structure is formed in the internal volume, which has at least one anchoring area fixed to the frame structure, the substrate surface and / or at least one intermediate layer and has at least one self-supporting area, which is connected to the inner side of the diaphragm via at least one coupling structure in such a way that the at least one self-supporting area can be bent by means of the warping of the diaphragm.

[0018] Advantages of the present invention

[0019] The present invention proposes a micromechanical component in which, due to the design of the flexure beam structure according to the invention, crack formation in its diaphragm is reliably prevented. The flexure beam structure according to the invention of this micromechanical component can be designed such that, even in the event of overload, when relatively high pressures act on the diaphragm, crack formation is reliably prevented, even in the clamping region of the respective diaphragm. Consequently, the conventional risk of failure of the micromechanical component or the sensor or microphone device constructed thereby due to cracks in its diaphragm is eliminated.

[0020] In one advantageous embodiment of the micromechanical component, at least one coupling structure is formed entirely from at least one electrically conductive material. In this case, the at least one coupling structure can typically be formed from the same material as the diaphragm (e.g., silicon). Consequently, the at least one coupling structure is relatively simple to construct and requires relatively little effort.

[0021] Alternatively, at least one coupling structure can be formed at least partially from at least one electrically insulating material. In this case, the potential applied to at least one free-standing region of the respective bending beam structure can differ from the potential applied to the adjacent membrane.

[0022] As an advantageous embodiment of the micromechanical component, at least one self-supporting region of the bent beam structure can span at least one counterelectrode arranged on the substrate surface and / or at least one intermediate layer, wherein the at least one counterelectrode is electrically insulated from the at least one self-supporting region of the bent beam structure, and a measurement signal can be tapped between the at least one self-supporting region of the bent beam structure and the at least one counterelectrode. As explained in more detail below, in this case, the measurement signal can serve as a "warning signal" for relatively high pressures acting on the diaphragm.

[0023] Alternatively or additionally, at least one protruding stop structure can also be formed on a surface of at least one self-supporting region of the bending beam structure that is directed away from the diaphragm. By means of the at least one stop structure, a maximum warping of the diaphragm can be mechanically limited.

[0024] In another advantageous embodiment of the micromechanical component, the bending beam structure and at least one reference electrode and / or at least one measuring electrode are formed from a first semiconductor layer and / or a metal layer, the at least one reference electrode being fixed to a frame structure, a substrate surface, and / or at least one intermediate layer; and / or the diaphragm, at least one coupling structure, and / or at least one suspension structure are formed from a second semiconductor layer and / or a metal layer, the at least one measuring electrode being suspended from the inner side of the diaphragm via the at least one suspension structure. Consequently, despite being equipped with at least one reference electrode and / or at least one measuring electrode, the micromechanical component described herein can be manufactured in a relatively simple and cost-effective manner.

[0025] Furthermore, the aforementioned advantages are also achieved by carrying out a corresponding production method for a micromechanical component of a sensor device or microphone device, wherein the production method can be expanded according to the aforementioned embodiments of the micromechanical component. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features and advantages of the present invention are described below based on the accompanying drawings.

[0027] Figure 1 A schematic diagram showing a conventional pressure sensor device;

[0028] Figure 2 A schematic partial view showing a first embodiment of a micromechanical component;

[0029] Figure 3a and 3b A schematic partial view showing a second embodiment of a micromechanical component;

[0030] Figure 4 A schematic partial view showing a third embodiment of a micromechanical component;

[0031] Figure 5 A schematic partial view showing a fourth embodiment of a micromechanical component;

[0032] Figure 6 A schematic partial view showing a fifth embodiment of a micromechanical component;

[0033] Figure 7 A schematic fragmentary illustration of a sixth embodiment of a micromechanical component is shown;

[0034] Figure 8 A schematic partial view shows a seventh specific embodiment of a micromechanical component;

[0035] Figure 9 a schematic fragmentary illustration showing an eighth specific embodiment of a micromechanical component; and

[0036] Figures 10 to 12Schematic illustrations of details of ninth, tenth and eleventh specific embodiments of the micromechanical component are shown. DETAILED DESCRIPTION

[0037] Figure 2 A schematic diagram of a detail of a first specific embodiment of a micromechanical component is shown.

[0038] exist Figure 2 The micromechanical component, shown schematically in part, comprises a substrate 10 having a substrate surface 10a, which can be, for example, a semiconductor substrate, in particular a silicon substrate. Substrate surface 10a is at least partially covered by at least one intermediate layer 12a and 12b. The at least one intermediate layer 12a and 12b can, for example, be at least one insulating layer 12a and 12b, in particular a silicon dioxide layer 12a and / or a silicon-rich silicon nitride layer 12b. Optionally, a conductor track layer 32 can be deposited on substrate surface 10a and / or the at least one intermediate / insulating layer 12a and 12b, wherein electrical contacts 32a can be formed, for example, by direct contact between substrate surface 10a and conductor track layer 32. Conductor track layer 32 can, for example, be a silicon layer.

[0039] The micromechanical component further comprises a frame structure 14, which is arranged on the substrate surface 10a and / or on at least one intermediate layer 12a and 12b. The diaphragm 16 spans the inner volume 18 at least partially surrounded by the frame structure 14 in such a way that the diaphragm inner side 16a of the diaphragm 16 adjoins the inner volume 18. Furthermore, the inner volume 18 is sealed in a gas-tight manner so that the diaphragm 16 can be warped / bent by means of a pressure difference between the internal pressure p1 present on its diaphragm inner side 16a and the external pressure p2 present on the diaphragm outer side 16b oriented away from the diaphragm inner side 16a. However, Figure 2 The micromechanical component is shown in the case of equal pressure between the internal pressure p1 and the external pressure p2.

[0040] Additionally, Figure 2 The micromechanical component includes a bending beam structure 34 arranged in the interior volume 18, which has at least one anchoring region 36 fixed to the frame structure 14, the substrate surface 10a, and / or at least one intermediate layer 12a and 12b, and at least one self-supporting region 38. The at least one self-supporting region 38 is connected to the diaphragm inner side 16a of the diaphragm 16 via at least one coupling structure 40 in such a way that the at least one self-supporting region 38 can be bent / flexed by warping the diaphragm 16. As illustrated in the figures based on the following embodiments, the bending beam structure 34 serves as a structural measure to reduce mechanical stresses that occur in the diaphragm 16, in particular in the clamping region 16c of the diaphragm 16, when there is a pressure difference between the internal pressure p1 and the external pressure p2.

[0041] As an optional expansion solution, Figure 2 The micromechanical component further includes a counter electrode 42 arranged on the substrate surface 10a and / or the at least one intermediate layer 12a and 12b, which spans the at least one self-supporting region 38 of the curved beam structure 34. The counter electrode 42 is electrically insulated from the at least one self-supporting region 38 of the curved beam structure 34. Furthermore, a measurement signal, such as a voltage signal, can be tapped between the at least one self-supporting region 38 of the curved beam structure 34 and the counter electrode 42.

[0042] In the event of significant warping of diaphragm 16, the distance d between at least one self-supporting region 38 of bending beam structure 34 and counter electrode 42 changes, which can be detected based on a change in the measurement signal (e.g., the tapped voltage). By arranging at least one coupling structure 40, via which at least one self-supporting region 38 of bending beam structure 34 is connected to diaphragm inner side 16a of diaphragm 16, it is possible to determine the degree of warping of diaphragm 16 at which a significant change in distance d, and therefore a significant change in the measurement signal, occurs. Thus, by evaluating the measurement signal, it can be determined whether critical warping of diaphragm 16 has occurred. If necessary, a corresponding warning signal can then be output to a user of the micromechanical component and / or to the control electronics operating the micromechanical component.

[0043] As in Figure 2 As can also be seen in the figure, the micromechanical component further includes at least one measuring electrode 22, which is suspended on the inner side 16a of the diaphragm 16 via at least one suspension structure 24. In particular, a respective measuring counter electrode 26 can be attached to the substrate surface 10a and / or at least one intermediate layer 12a and 12b between the at least one measuring electrode 22 and the substrate 10. The interaction of the at least one measuring electrode 22 and the at least one measuring counter electrode 26 allows the detection of a pressure difference between the internal pressure p1 and the external pressure p2, or in other words, the detection of sound waves impinging on the outer side 16b of the diaphragm. Therefore, the micromechanical component described herein can be advantageously used in a sensor device or microphone device.

[0044] Preferably, the minimum distance between the at least one coupling structure 40 and the clamping region 16 c of the diaphragm 16 is smaller than the minimum distance between the at least one suspension structure 24 and the clamping region 16 c.

[0045] In this case, the at least one measuring electrode 22 is preferably "centrally suspended" on the diaphragm 16, while the bending beam structure 34 is preferably arranged close to or directly on the clamping region 16c of the diaphragm 16. In particular, high bending forces occur on the clamping region 16c of the diaphragm 16 in overload situations. Therefore, it is advantageous to absorb the deformation forces / deformation energy acting on the clamping region 16c in such situations by means of the at least one coupling structure 40 and the bending beam structure 34. The geometric dimensions and shape of the bending beam structure 34 and the spacing of the at least one coupling structure 40 from the clamping region 16c of the diaphragm 16 determine the force that counteracts the deformation forces / deformation energy on the diaphragm 16 at the location of the at least one coupling structure 40. Furthermore, the "central suspension" of the at least one measuring electrode 22 on the diaphragm 16 ensures good sensitivity when detecting the pressure difference between the internal pressure p1 and the external pressure p2, or when detecting sound waves impinging on the outer side 16b of the diaphragm.

[0046] Optionally, Figure 2 The micromechanical component can be designed to be mirror-symmetrical with respect to the symmetry plane 44. Alternatively, however, a reference electrode 28 can also be arranged on the side of the measuring electrode 22 that is oriented away from the bending beam structure 34, which reference electrode has a corresponding reference counter electrode 30, such as these reference electrodes and the reference counter electrode, for example, Figure 1 As shown in .

[0047] Even in series production, the following production method can be used to produce the Figure 2 The micromechanical components shown in the figure are partially shown:

[0048] To implement this manufacturing method, a first semiconductor and / or metal layer 46 is deposited on substrate surface 10a, at least one intermediate layer 12a and 12b, conductor track layer 32, and / or at least one first sacrificial layer 48. The first semiconductor and / or metal layer 46 can be, for example, a silicon layer. The at least one first sacrificial layer 48 can be, in particular, a silicon dioxide layer. Furthermore, a second semiconductor and / or metal layer 50 is deposited on the first semiconductor and / or metal layer 46 and / or the at least one second sacrificial layer 52. The second semiconductor and / or metal layer 50 can also be a silicon / polysilicon layer. The at least one second sacrificial layer 52 can be, for example, a silicon dioxide layer.

[0049] Preferably, frame structure 14 is formed from at least a portion of conductor track layer 32, from at least a portion of first semiconductor layer and / or metal layer 46, and from at least a portion of second semiconductor layer and / or metal layer 50 in such a manner that frame structure 14 formed on substrate surface 10a and / or at least one intermediate layer 12a and 12b at least partially surrounds (later) interior volume 18. Diaphragm 16 spans interior volume 18 in such a manner that diaphragm inner side 16a of diaphragm 16 adjoins interior volume 18, wherein diaphragm 16 is formed from second semiconductor layer and / or metal layer 50. Bent beam structure 34 is formed / structured from first semiconductor layer and / or metal layer 46 in such a manner that bent beam structure 34 is arranged in interior volume 18 and is configured with at least one anchoring region 36 secured to frame structure 14, substrate surface 10a, and / or at least one intermediate layer 12a and 12b, and is configured with at least one self-supporting region 38. At least one coupling structure 40 can also be formed by a second semiconductor layer and / or a metal layer 50, with the help of which at least one coupling structure 40 at least one self-supporting area 38 is connected to the inner side 16a of the diaphragm 16 in such a way that the at least one self-supporting area 38 can be bent by means of the warping of the diaphragm 16.

[0050] As in Figure 1 and Figure 2 As can be seen in the figure, in addition to the curved beam structure 34, at least one reference electrode 28 and / or at least one measuring electrode 22 can be formed / structured from the first semiconductor layer and / or metal layer 46. This at least one reference electrode is fixed to the frame structure 14, the substrate surface 10a, and / or the at least one intermediate layer 12a and 12b. In addition to the diaphragm 16 and possibly at least one coupling structure 40, at least one suspension structure 24 can also be formed from the second semiconductor layer and / or metal layer 50, by which at least one measuring electrode 22 is suspended from the diaphragm inner side 16a. Furthermore, the counter electrode 42, the at least one measuring counter electrode 26, and / or the at least one reference counter electrode 30 can be formed / structured from the conductor track layer 32.

[0051] After at least partial removal / etching of sacrificial layers 48 and 52 (preferably at a desired internal pressure p1), interior volume 18 is sealed in a gas-tight manner, for example by depositing an insulating layer 54 on at least a partial outer surface of the second semiconductor layer and / or metal layer 50 surrounding at least one etched opening. The at least one partial outer surface is preferably understood to be the surface of the second semiconductor layer and / or metal layer 50 directly adjacent to the corresponding etched opening. In this way, it is possible to ensure that diaphragm 16 can be warped / bent due to the pressure difference between the internal pressure p1 prevailing on its diaphragm inner side 16a and the external pressure p2 (currently) prevailing on its outer side 16b. Optionally, at least one electrical contact 56a can be formed by metallization 56 (e.g., aluminum-copper) and / or optional contact metallization 56b (e.g., TiSi2 / Ti) and / or an optional diffusion barrier (e.g., TiN). As a further optional method step, a passivation 58 , for example silicon nitride (Si 3 N 4 ), may also be deposited on the metallization 56 and the insulation layer 54 .

[0052] Figure 3a and 3b A schematic diagram of a detail of a second specific embodiment of a micromechanical component is shown.

[0053] As a supplement to the above embodiment, Figure 3a and 3b The micromechanical component shown schematically in part also has at least one reference electrode 28, which is fixed to the frame structure 14, the substrate surface 10a and / or the at least one intermediate layer 12a and 12b. The at least one reference electrode 28 spans a respective reference counter electrode 30. With the aid of the at least one reference electrode 28 and its at least one reference counter electrode 30, a reference capacitance measurement can be performed in order to "filter out" or correct for changes in the distance / measurement signal between the at least one measuring electrode 22 and its at least one measuring counter electrode 26 that can be attributed to a bending of the substrate 10. As shown in Figure 3a and 3b As can be seen in FIG, at least one reference electrode 28 can be formed / structured out of the first semiconductor layer and / or metal layer 46, and its at least one reference counter electrode 30 can be formed / structured out of the printed conductor layer 32. In particular, the curved beam structure 34, its counter electrode 42, the adjacent reference electrode 28 and the adjacent reference counter electrode 30 can be formed / structured out of the printed conductor layer 32 by means of a structured structure of each continuous intermediate gap 60. Figure 1 A “conventional” reference electrode 28 and its corresponding reference counter electrode 30 are formed.

[0054] exist Figure 3a In the diagram of , the external pressure p2 is equal to the internal pressure p1 in the inner volume 18. Conversely, in Figure 3bIn the illustration, the external pressure p2 is higher than the internal pressure p1. It can be seen that in this case, the warping of diaphragm 16 triggers the bending of at least one self-supporting region 38 of bending beam structure 34. This causes a change in the distance d between at least one self-supporting region 38 of bending beam structure 34 and the corresponding counter electrode 42, thereby absorbing energy or generating a reaction force on diaphragm 16. As a result, diaphragm 16 warps less strongly than in the prior art. This reduces the mechanical stresses that occur in the warped diaphragm 16 (particularly in the clamping region 16c of diaphragm 16). Consequently, the formation of cracks in diaphragm 16 can be reliably counteracted by means of bending beam structure 34. Consequently, even when diaphragm 16 is relatively thin, there is no need to worry about crack formation in diaphragm 16. Consequently, the risk of failure of the micromechanical component due to cracks in its diaphragm 16 is significantly reduced compared to the prior art.

[0055] It should also be noted that the reaction force, or the amount of energy absorbed by the bending beam structure 34, can be determined by the length of the at least one self-supporting region 38 of the bending beam structure 34, oriented parallel to the substrate surface 10a; the width of the at least one self-supporting region 38 of the bending beam structure 34, oriented perpendicular to the substrate surface 10a; and the shape of the at least one self-supporting region 38 of the bending beam structure 34. The reaction force exerted by the at least one self-supporting region 38 of the bending beam structure 34 on the diaphragm 16 at the location of the at least one coupling structure 40 can also be "adjusted" by the position of the at least one coupling structure 40. By means of the geometric dimensions and shape of the at least one self-supporting region 38 of the bending beam structure 34, as well as the spacing of the at least one coupling structure 40 from the clamping region 16c of the diaphragm 16, the bending of the diaphragm 16 (due to the existing external pressure p2) can be resisted to a greater or lesser extent in a targeted manner. Thus, the reaction force, or the amount of energy absorbed by the bending beam structure 34, can be flexibly adjusted. By using a plurality of coupling structures 40 on each self-supporting region 38 , it is also possible to “model” or adjust the resulting diaphragm deflection or bending in a better or more defined manner when pressure is applied to the diaphragm outer side 16 b .

[0056] about Figure 3a and 3b For other properties and characteristics of micromechanical components and their advantages, see Figure 2 implementation method.

[0057] Figure 4 A schematic partial view of a third specific embodiment of a micromechanical component is shown.

[0058] exist Figure 4In an embodiment, the self-supporting region 38 of the bending beam structure 34 extends over an electrically conductive structure 62 arranged on the substrate surface 10a and / or on at least one of the intermediate layers 12a and 12b, which is at the same electrical potential as the self-supporting region 38 of the bending beam structure 34 (and possibly the diaphragm 16). By means of the electrical connection of the electrically conductive structure 62 to the bending beam structure 34, variable reference capacitances and stray capacitances can be avoided when the diaphragm 16 is loaded with pressure. For example, the self-supporting region 38 extends away from the associated anchoring region 36 of its bending beam structure 34 and away from the clamping region 16 c of the diaphragm 16 .

[0059] about Figure 4 For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0060] Figure 5 A schematic partial view of a fourth specific embodiment of a micromechanical component is shown.

[0061] exist Figure 5 In the micromechanical component, the self-supporting region 38 of its bending beam structure 34 extends away from the corresponding anchoring region 36 toward the clamping region 16 c of the diaphragm. Therefore, the mechanical force / energy coupling into the bending beam structure 34 via its coupling structure 40 occurs near the clamping region 16 c of the diaphragm 16.

[0062] about Figure 5 For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0063] Figure 6 A schematic partial view of a fifth specific embodiment of a micromechanical component is shown.

[0064] exist Figure 6 In the micromechanical component of FIG, the bending beam structure 34 has two anchoring regions 36, each of which has a self-supporting region 38, which is connected to the inner side 16a of the diaphragm via at least one coupling structure 40. It can be seen that this configuration of the bending beam structure 34 can be achieved by means of a continuous intermediate gap 60. Figure 1 The diaphragm 16 is constructed as a "conventional" reference electrode 28. This bending beam structure 34 provides the possibility of applying a respective reaction force to the diaphragm inner side 16a of the diaphragm 16 at at least two different locations on the diaphragm 16. Furthermore, by designing the two self-supporting regions 38, in particular their (possibly different) lengths, (possibly different) widths, (possibly different) heights, and (possibly different) shapes, the respective reaction forces can be influenced in order to determine the bending of the diaphragm 16 when pressure is applied to the diaphragm outer side 16b in accordance with the desired target bending / target deformation.

[0065] about Figure 6 For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0066] Figure 7 A schematic partial view of a sixth specific embodiment of a micromechanical component is shown.

[0067] As an extension of the above embodiment, Figure 7 The micromechanical component also has at least one protruding stop structure 64 on the surface of at least one self-supporting region 38 of the bending beam structure 34, which is oriented away from the diaphragm 16. With the help of the at least one stop structure 64, the maximum deflection of the at least one self-supporting region 38 in the direction of the substrate 10 can be limited. Correspondingly, the maximum warping of the diaphragm 16 can also be limited with the help of the at least one stop structure 64. Preferably, each stop structure 64 and each coupling structure 40 extend along a common axis 66. This can also be rewritten so that the at least one stop structure 64 is located within the "longitudinal axis of extension" of the at least one coupling structure 40. This has the following advantage: when the at least one stop structure 64 is in contact with the contact structure, the substrate surface 10a and / or the at least one intermediate layer 12a and 12b, the force coupling input into the diaphragm 16 is directly transferred further into the substrate 10 via the at least one coupling structure 40, the at least one self-supporting region 38 and the at least one stop structure 64. Figure 7 In the exemplary embodiment, in the event of a strong warping of the membrane 16 , the at least one stop structure 64 contacts, for example, at least one of the intermediate layers 12 a and 12 b .

[0068] Alternatively, if necessary, a "resilient stop" of at least one self-supporting area 38 of the curved beam structure 34 can also be constructed by positioning at least one stop structure 64 offset relative to at least one coupling structure 40, or positioning at least one stop structure outside the "extended longitudinal axis" of at least one coupling structure 40.

[0069] about Figure 7 For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0070] Figure 8 A schematic partial view of a seventh specific embodiment of a micromechanical component is shown.

[0071] As a supplement to the above implementation, Figure 8The micromechanical component further comprises a contact structure 68, which contacts the at least one stop structure 64 in the event of a significant deflection of the diaphragm 16. The contact structure 68 can be formed / structured by the conductor track layer 32, but is preferably designed to be electrically insulated from its immediate surroundings. Alternatively, the contact structure 68 can have the same electrical potential as the at least one stop structure and / or the at least one self-supporting region 38 of the bending beam structure 34.

[0072] about Figure 8 For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0073] Figure 9 A schematic partial view of an eighth specific embodiment of a micromechanical component is shown.

[0074] exist Figure 9 In the micromechanical component, it is omitted to construct at least one protruding stop structure 64 on at least one self-supporting area 38 of its bending beam structure 34. However, Figure 9 The micromechanical component has the contact structure 68 described above, against which at least one end of at least one self-supporting region 38 of its bending beam structure 34 strikes when diaphragm 16 is strongly warped. Even without the need for at least one protruding stop structure 64 on at least one self-supporting region 38, the maximum warping of diaphragm 16 can be determined using contact structure 68.

[0075] about Figure 9 For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0076] Alternatively, in Figure 8 and 9 In a variant of the embodiment of FIG. 5 , the electrically conductive structure 62 can also be used (instead of the contact structure 68 ) to determine the maximum warping of the membrane 16 .

[0077] Figures 10 to 12 Schematic illustrations of details of ninth, tenth and eleventh specific embodiments of the micromechanical component are shown.

[0078] Figures 10 to 12 Micromechanical components and Figure 6 The embodiment differs only in that the geometric dimensions of the region of frame structure 14 extending from bending beam structure 34 to diaphragm 16, the geometric dimensions of the region of frame structure 14 extending from bending beam structure 34 to conductor track layer 32, and / or the geometric dimensions of the further anchoring region 36 of bending beam structure 34 are at least partially enlarged. In this way, the amount of energy absorbed by bending beam structure 34 can also be determined and the bending / deformation of diaphragm 16 can be influenced when external pressure p2 is applied.

[0079] about Figures 10 to 12For other properties and features of the micromechanical component and its advantages, please refer to the above embodiments.

[0080] In all of the aforementioned micromechanical components, the amount of energy absorbed by their bending beam structure 34 can be determined by relatively freely selecting the length of at least one self-supporting region 38, the width of at least one self-supporting region 38, the height of at least one self-supporting region 38, the shape of at least one self-supporting region 38, and the position of at least one coupling structure 40. The at least one coupling structure 40 can be formed entirely from at least one electrically conductive material, for example, by being formed / structured entirely from the second semiconductor layer and / or metal layer 50. Alternatively, the at least one coupling structure 40 can be formed at least partially from at least one electrically insulating material, such as, in particular, silicon-rich silicon nitride. If the at least one coupling structure 40 is at least partially constructed from silicon-rich silicon nitride, etching materials typically used to etch sacrificial layers 48 and 52 (e.g., HF or BOE) do not attack or barely attack the silicon-rich silicon nitride.

[0081] All of the aforementioned micromechanical components can be manufactured using the described manufacturing method. As an extension, at least one protruding stop structure 64 may also be formed on the surface of at least one self-supporting region 38 of the bending beam structure 34, which surface is oriented away from the diaphragm 16. The frame structure 14, the at least one suspension structure 24 of the at least one measuring electrode 22, and / or the anchoring region 36 can be designed to be at least partially electrically insulating. For example, silicon-rich silicon nitride can be used as the electrically insulating material to form the frame structure 14 and / or the anchoring region 36. Furthermore, the semiconductor layers can be selectively doped to improve electrical conductivity.

Claims

1. A micromechanical component for a sensor device or a microphone device, comprising: a substrate (10) having a substrate surface (10a); a frame structure (14) arranged on the substrate surface (10a) and / or at least one intermediate layer (12a, 12b) at least partially covering the substrate surface (10a); and a membrane (16) which spans an inner volume (18) at least partially surrounded by the frame structure (14) such that an inner membrane side (16a) of the membrane (16) abuts the inner volume (18); in, The inner volume (18) is sealed in a gas-tight manner such that the diaphragm (16) can be warped by a pressure difference between an internal pressure (p1) existing on its diaphragm inner side (16a) and an external pressure (p2) existing on the diaphragm outer side (16b) of the diaphragm (16) directed away from the diaphragm inner side (16a), It is characterized by A bending beam structure (34) is arranged in the inner volume (18), the bending beam structure having at least one anchoring region (36) fixed to the frame structure (14), the substrate surface (10a) and / or the at least one intermediate layer (12a, 12b) and having at least one self-supporting region (38), the at least one self-supporting region being connected to the inner side (16a) of the diaphragm (16) via at least one coupling structure (40) in such a way that the at least one self-supporting region (38) can be bent by means of a warping of the diaphragm (16).

2. The micromechanical component according to claim 1, wherein The at least one coupling structure (40) is formed entirely from at least one electrically conductive material (50).

3. The micromechanical component according to claim 1, wherein: The at least one coupling structure (40) is at least partially formed from at least one electrically insulating material.

4. The micromechanical component according to claim 1, wherein: At least one self-supporting area (38) of the curved beam structure (34) spans over at least one counter electrode (42) arranged on the substrate surface (10a) and / or the at least one intermediate layer (12a, 12b), wherein the at least one counter electrode (42) is electrically insulated from the at least one self-supporting area (38) of the curved beam structure (34) and is capable of intercepting a measurement signal between the at least one self-supporting area (38) of the curved beam structure (32) and the at least one counter electrode (42).

5. The micromechanical component according to claim 1, wherein: At least one protruding stop structure (64) is formed on a surface of at least one self-supporting region (38) of the bending beam structure (34) that is oriented away from the diaphragm (16).

6. The micromechanical component according to claim 1, wherein: The bending beam structure (34) and at least one reference electrode (28) and / or at least one measuring electrode (22) are formed by a first semiconductor layer and / or a metal layer (46), and the at least one reference electrode is fixed on the frame structure (14), the substrate surface (10a) and / or the at least one intermediate layer (12a, 12b); and / or the diaphragm (16), the at least one coupling structure (40) and / or the at least one suspension structure (24) are formed by a second semiconductor layer and / or a metal layer (50), and the at least one measuring electrode (22) is suspended on the inner side (16a) of the diaphragm by means of the suspension structure.

7. A method for producing a micromechanical component for a sensor device or a microphone device, the method comprising the following steps: forming a frame structure (14) on a substrate surface (10a) of a substrate (10) and / or on at least one intermediate layer (12a, 12b) at least partially covering the substrate surface (10a); and spanning an inner volume (18) at least partially surrounded by the frame structure (14) by means of a membrane (16) such that a membrane inner side (16a) of the membrane (16) adjoins the inner volume (18); in, The inner volume (18) is sealed in a gas-tight manner such that the diaphragm (16) can be warped by a pressure difference between an internal pressure (p1) existing on its diaphragm inner side (16a) and an external pressure (p2) existing on the diaphragm outer side (16b) of the diaphragm (16) directed away from the diaphragm inner side (16a), It is characterized by the following steps: A bending beam structure (34) is formed in the inner volume (18), comprising at least one anchoring region (36) fixed to the frame structure (14), the substrate surface (10a) and / or the at least one intermediate layer (12a, 12b) and comprising at least one self-supporting region (38), which is connected to the inner side (16a) of the diaphragm (16) via at least one coupling structure (40) in such a way that the at least one self-supporting region (38) can be bent by means of a warping of the diaphragm (16).

8. The manufacturing method according to claim 7, wherein: At least one protruding stop structure (64) is formed on a surface of at least one self-supporting region (38) of the bending beam structure (34) that is oriented away from the diaphragm (16).

9. The manufacturing method according to claim 7 or 8, wherein: At least the bending beam structure (34) is formed by a first semiconductor layer and / or a metal layer (46), which covers the substrate surface (10a), the at least one intermediate layer (12a, 12b), the printed conductor layer (32) and / or at least one first sacrificial layer (48), wherein the diaphragm (16) and / or the at least one coupling structure (40) are formed by a second semiconductor layer and / or a metal layer (50), which covers the first semiconductor layer and / or the metal layer (46) and / or the at least one second sacrificial layer (52).

10. The manufacturing method according to claim 9, wherein: In addition to the bending beam structure (34), at least one reference electrode (28) and / or at least one measuring electrode (22) is formed by the first semiconductor layer and / or the metal layer (46), the at least one reference electrode being fixed to the frame structure (14), the substrate surface (10a) and / or the at least one intermediate layer (12a, 12b), and / or, in addition to the diaphragm (16) and / or the at least one coupling structure (40), at least one suspension structure (24) is formed by the second semiconductor layer and / or the metal layer (50), by means of which the at least one measuring electrode (22) is suspended on the inner side (16a) of the diaphragm.

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