Micromechanical structure for a sensor device or a microphone device

Abstract

The invention relates to a micromechanical component for a sensor device or a microphone device, having a membrane (10) with a membrane inner side (10a), an electrode structure (12) being attached at least partially directly or indirectly to the membrane inner side, a cavity (14) being configured at least in a volume exposed by at least one removal region of at least one sacrificial layer (16, 18), wherein at least one residual region (16a, 18a) made of at least one electrically insulating sacrificial layer material of the at least one sacrificial layer (16, 18) remains on the micromechanical component, and at least one insulating region (20a, 20b) made of at least one electrically insulating material different from the at least one electrically insulating sacrificial layer material, wherein the electrode structure (12) is electrically insulated from the membrane (10) and / or the at least one residual region (16a, 18a) of the at least one sacrificial layer (16, 18) is separated from the cavity (14) by means of the at least one insulating region (20a, 20b). The invention also relates to a manufacturing method for a micromechanical component for a sensor device or a microphone device.

Description

Technical Field

[0001] This invention relates to a micromechanical component for use in sensor devices or microphone devices. The invention also relates to a method for manufacturing the micromechanical component for use in sensor devices or microphone devices. Background Technology

[0002] A capacitive pressure sensor is described in DE 10 2007 029414 A1, in which adjustable electrodes protruding toward a substrate are formed on a diaphragm of the capacitive pressure sensor. Summary of the Invention

[0003] The present invention provides a micromechanical component for a sensor device or microphone device having the features of claim 1, and a method for manufacturing the micromechanical component for a sensor device or microphone device having the features of claim 5.

[0004] Advantages of the invention

[0005] Based on the inventive construction of a micromechanical component comprising at least one sacrificial layer made of at least one electrically insulating sacrificial layer material, and the inventive construction of the same micromechanical component comprising at least one insulating region made of at least one electrically insulating material different from the at least one electrically insulating sacrificial layer material, a process suitable for partially removing at least one sacrificial layer can be implemented to construct the cavity of the micromechanical component without concern for damaging or removing at least one insulating region. Therefore, the present invention simplifies equipping a corresponding micromechanical component according to the invention with at least one insulating region, which is advantageously suited for electrically insulating the electrode structure from the diaphragm, electrically insulating between the diaphragm material layer and the electrode material layer, and / or separating at least one residual region of at least one sacrificial layer from the cavity. Thus, the present invention improves upon the micromechanical component according to the invention compared to the prior art, and additionally helps to reduce the labor costs and manufacturing costs associated with manufacturing the micromechanical component according to the invention.

[0006] At least one insulating region used to separate at least one residual region of at least one sacrificial layer can in particular serve as "etch protection" to prevent undesirable etching of at least one residual region during cavity construction. Simultaneously, the at least one insulating region constructed from at least one electrically insulating material for separating at least one residual region enables the limiting of the circuit path by corresponding micromechanical components.

[0007] In an advantageous embodiment of the micromechanical component, at least one residual region is composed of silicon dioxide or silicon-rich silicon nitride. In this case, at least one sacrificial layer in the cavity is preferably composed of silicon dioxide. Silicon dioxide can be etched with a wide range of etching media, thereby enabling the cavity to be constructed by partially removing at least one sacrificial layer formed of silicon dioxide.

[0008] Preferably, at least one insulating region is composed of silicon nitride, silicon-rich silicon nitride, silicon carbide, and / or alumina as at least one electrical insulating material. The materials listed herein have advantageous etch resistance to a wide range of etch media, allowing at least one sacrificial layer to be etched without concern for damaging or removing at least one insulating region.

[0009] In particular, at least one residual region can be made of silicon dioxide as at least one electrically insulating sacrificial layer material, while at least one insulating region can be made of silicon nitride, silicon-rich silicon nitride, silicon carbide, and / or alumina as at least one electrically insulating material. In this case, hydrogen fluoride vapor-phase etching can be performed to form a cavity, wherein at least one insulating region is not or hardly eroded due to the advantageous etch resistance of silicon nitride, silicon-rich silicon nitride, silicon carbide, and alumina (to hydrogen fluoride). Thus, the embodiments of the micromechanical components described herein can be manufactured in a relatively cost-effective manner using simple implementation steps.

[0010] As an advantageous extension of the micromechanical components, at least one conductive element can be electrically contacted with a wiring layer that at least partially covers the substrate surface of the substrate as at least one intermediate layer. The electrode structure is electrically attached to the at least one conductive element via at least one spring-shaped conductor rail, and the at least one conductive element, the at least one spring-shaped conductor rail, and the electrode structure are formed from a common electrode material layer. As explained more precisely below, the at least one spring-shaped conductor rail can advantageously be used for electrically contacting the electrode structure, although the electrode structure can be adjusted by means of diaphragm warping. Furthermore, since the at least one spring-shaped conductor rail and the electrode structure are constructed from a common electrode material layer, the labor cost required to form the at least one spring-shaped conductor rail is relatively low.

[0011] The aforementioned advantages can also be ensured by implementing corresponding manufacturing methods for micromechanical components used in sensor devices or microphone devices.

[0012] In an advantageous embodiment of the manufacturing method, removal of at least one region of at least one sacrificial layer made of at least one electrically insulating sacrificial layer material is achieved by etching the corresponding region of the at least one sacrificial layer with an etching medium, wherein the at least one electrically insulating material of the at least one insulating region has higher etch resistance than the at least one electrically insulating sacrificial layer material to the etching medium. Thus, cavities can be formed by appropriately selecting the etching medium without incurring the cost of damaging or removing at least one insulating region.

[0013] In another advantageous embodiment of the manufacturing method, in order to determine the volume of the subsequent cavity and to form the electrode structure, the substrate surface of the substrate and / or at least partially covering at least one intermediate layer of the substrate surface is covered as a first sacrificial layer of at least one sacrificial layer made of at least one electrically insulating sacrificial layer material, the side of the first sacrificial layer facing away from the substrate being at least partially covered by an electrode material layer such that the electrode structure is formed by at least a sub-region of the electrode material layer, and the side of the electrode material layer facing away from the first sacrificial layer being at least partially covered by a second sacrificial layer of the at least one sacrificial layer made of the at least one electrically insulating sacrificial layer material. The method steps described herein can be implemented in a relatively simple manner, wherein relatively low costs are incurred for their implementation. Attached Figure Description

[0014] Other features and advantages of the invention are described below with reference to the accompanying drawings. The drawings show:

[0015] Figure 1a and Figure 1b A schematic diagram illustrating one embodiment of a micromechanical component and a flowchart illustrating one embodiment of a method for manufacturing a micromechanical component for a sensor device or microphone device; and

[0016] Figure 2 Figure 13 shows schematic diagrams or partial schematic diagrams of other embodiments of the micromechanical components. Detailed Implementation

[0017] Figure 1a and Figure 1b A schematic diagram illustrating one embodiment of a micromechanical component and a flowchart illustrating one embodiment of a method for manufacturing a micromechanical component for a sensor device or microphone device are shown.

[0018] Figure 1aThe schematically reproduced micromechanical component has a diaphragm 10 having an inner diaphragm side 10a, wherein an electrode structure 12 is at least partially directly or indirectly attached to the inner diaphragm side 10a. The electrode structure 12 thus provides advantageous reinforcement of the diaphragm 10 and can be implemented as fully or at least partially perforated. A cavity 14 of the micromechanical component is at least constructed in a volume exposed by at least one removal region of at least one sacrificial layer 16 and 18, such that the inner diaphragm side 10a of the diaphragm 10 is adjacent to the cavity 14. Additionally, the electrode structure 12, directly or indirectly attached to the inner diaphragm side 10a, is at least partially surrounded by the cavity 14. The phrase "the cavity 14 is at least constructed in a volume exposed by at least one removal region of at least one sacrificial layer 16 and 18" can be identified by the presence of at least one residual region 16a and 18a made of at least one electrically insulating sacrificial layer material of at least one sacrificial layer 16 and 18 on the micromechanical component.

[0019] Furthermore, the micromechanical component has at least one insulating region 20a made of at least one electrically insulating material different from at least one electrically insulating sacrificial layer material. In the embodiment of FIG1, at least one residual region 16a and 18a of at least one sacrificial layer 16 and 18 is separated from the cavity 14 by means of at least one insulating region 20a. Further uses of such insulating regions made of at least one electrically insulating material different from at least one electrically insulating sacrificial layer material will be discussed below.

[0020] Preferably, at least one residual region 16a and 18a of at least one sacrificial layer 16 and 18 is composed of silicon dioxide as at least one electrically insulating sacrificial layer material. In this case, at least one insulating region 20a is preferably composed of silicon nitride, silicon-rich silicon nitride, silicon carbide, and / or alumina as at least one electrically insulating material. As will be explained more precisely below, this simplifies the manufacturability of the micromechanical component.

[0021] Figure 1a Micromechanical components can be used with the help of Figure 1b The manufacturing method is schematically reproduced in the diagram. Therefore, in the description Figure 1b The manufacturing method was discussed Figure 1a Other features of micromechanical components:

[0022] In the manufacturing method described herein, in method step S1, the volume of the subsequent cavity 14 of the subsequent micromechanical component is determined at least by forming at least one sacrificial layer 16 and 18 made of at least one electrically insulating sacrificial layer material. Additionally, in method step S1, an electrode structure 12 is formed that is at least partially surrounded by the volume of the subsequent cavity 14.

[0023] However, alternatively, method step S0 may be performed prior to method step S1. As method step S0, the substrate surface 22a of substrate 22 may be at least partially covered by at least one intermediate layer 24 to 28. Substrate 22 may, in particular, be a silicon substrate. As at least one intermediate layer 24 to 28, for example, at least one insulating layer 24 and 26 (e.g., especially a silicon dioxide layer 24 and / or a silicon-rich silicon nitride layer 26) may be deposited on the substrate surface 22a of substrate 22. Optionally, a wiring layer 28 may also be deposited as at least one intermediate layer 24 to 28 on the substrate surface 22a and / or at least one insulating layer 24 and 26. At least one counter electrode 30a and 30b may be formed from the wiring layer 28, for example; the function of this counter electrode will be discussed below. Optionally, at least one substrate contact 32 may also be constructed by partially planarly depositing the wiring layer 28 on the substrate surface 22a. Furthermore, at least one (not shown) non-flexible conductor track and / or at least one (not shown) electrical contact may also be formed from the wiring layer 28. Wiring layer 28 may be made of doped silicon / polysilicon and / or metal (e.g., aluminum) and / or metal-containing layer (e.g., metal silicide).

[0024] The method steps S1 for determining the volume of the subsequent cavity 14 and for forming the electrode structure 12 may include a plurality of sub-steps S1a to S1c. First, in sub-step S1a, the substrate surface 22a of the substrate 22 and / or at least one intermediate layer 24 to 28 that at least partially covers the substrate surface 22a may be covered by a first sacrificial layer 16 as at least one sacrificial layer 16 and 18 made of at least one electrically insulating sacrificial layer material. Next, as in sub-step S1b, the side of the first sacrificial layer 16 that is oriented away from the substrate 22 may be at least partially covered by an electrode material layer 34 such that the electrode structure 12 is formed by at least a sub-region of the electrode material layer 34. Optionally, at least one reference electrode 36 may also be constructed together with the electrode material layer 34. While the electrode structure 12 can function as a measurement capacitor together with the counter electrode 30a formed by the wiring layer 28, at least one reference electrode 36 may form a reference capacitor with at least one associated reference counter electrode 30b also formed by the wiring layer 28. Optionally, at least one connection 37 between the wiring layer 28 and the electrode material layer 34 may also be formed of the material of the electrode material layer 34. For example, the electrode material layer 34 may be formed of doped silicon / polysilicon. Sub-step S1c may be performed after sub-step S1b, in which the side of the electrode material layer 34 facing away from the first sacrificial layer 16 is at least partially covered by a second sacrificial layer 18, which is at least one sacrificial layer 16 and 18 made of at least one electrically insulating sacrificial layer material.

[0025] In step S2 of the manufacturing method described herein, at least one insulating region 20a is formed of at least one electrically insulating material different from at least one electrically insulating sacrificial layer material, such that at least one subsequent residual region 16a and 18a of at least one sacrificial layer 16 and 18 is separated from the subsequent cavity by at least one insulating region 20a. This can be achieved in a simple manner by depositing at least one electrically insulating material on the portion of the electrode material layer 34 that is kept free / exposed by the second sacrificial layer 18. By subsequent processes, such as by plasma etching and / or CMP (Chemical Mechanical Polishing), at least one electrically insulating material can again be removed from the second sacrificial layer 18 such that it remains only in the region of the second sacrificial layer 18 that was removed to keep the portion of the electrode material layer 34 free / exposed.

[0026] Alternatively, at least one electrically insulating material may be applied and structured onto the electrode material layer 34. If a portion of the surface of at least one electrically insulating material on the electrode material layer 34 is exposed after the application of the second sacrificial layer 18, material of the membrane material layer 38 may be deposited in at least one removal region of the second sacrificial layer 18 (in subsequent step S3). In this way, it is possible to create at least one region in which the membrane material layer 38 is in direct contact with the electrode material layer 34, for example, to form an electrical contact between the two layers; and simultaneously create at least one region in which an insulating region 20a prevents the formation of the electrical contact. The region preventing the formation of the electrical contact can advantageously be used to separate at least one residual region 16a and 18a of at least one sacrificial layer 16 and 18 from the subsequent cavity.

[0027] In another method step S3 of the manufacturing method described herein, a diaphragm 10, having a defined cavity 14, is formed as an inner side 10a of the diaphragm, which is subsequently a micromechanical component, wherein the electrode structure 12 is directly or indirectly attached to the inner side 10a of the diaphragm. To form the diaphragm 10, a diaphragm material layer 38 may be deposited, for example, on the second sacrificial layer 18, on the surface of the electrode material layer 34 that remains free / exposed, and / or on at least one insulating region 20a. The diaphragm material layer 38 may be formed, for example, from doped silicon / polysilicon. Figure 1a As can be identified, the electrode structure 12 can be directly fixed to the diaphragm 10 by depositing the membrane material layer 38 directly on at least one of the free / exposed surfaces of the electrode structure 12.

[0028] A cavity 14 is formed by means of method step S4, wherein method step S4 includes removing at least one region of at least one sacrificial layer 16 and 18 made of at least one electrically insulating sacrificial layer material at least once, and performing this removal such that the inner side 10a of the diaphragm is adjacent to the cavity 14 and the electrode structure 12 directly or indirectly attached to the inner side 10a of the diaphragm is at least partially surrounded by the cavity 14. After performing method step S4, at least one residual region 16a and 18a of at least one sacrificial layer 16 and 18 made of at least one electrically insulating sacrificial layer material remains on the micromechanical component.

[0029] Removal of at least one region of at least one sacrificial layer 16 and 18 made of at least one electrically insulating sacrificial layer material is preferably achieved by etching the corresponding region of at least one sacrificial layer 16 and 18 with an etching medium for which at least one electrically insulating material of at least one insulating region 20a has significantly higher etch resistance than the at least one electrically insulating sacrificial layer material. If at least one sacrificial layer 16 and 18 are formed (only) of silicon dioxide as at least one electrically insulating sacrificial layer material and at least one insulating region 20a is formed (only) of silicon nitride, silicon-rich silicon nitride, silicon carbide, and / or alumina as at least one electrically insulating material, the etching medium may be, for example, hydrogen fluoride in liquid or gaseous form. By using hydrogen fluoride in liquid or gaseous form as the etching medium, at least one region of at least one sacrificial layer 16 and 18 can be removed quickly and reliably without concern for undesirable (co)etching ((Mit-)). At least one insulating region 20a.

[0030] During step S4 of the method, at least one insulating region 20a thus ensures that electrical insulation between the film material layer 38 and the electrode material layer 34 is achieved locally or at a defined location, and that at least one desired residual region 16a and 18a of at least one sacrificial layer 16 and 18 remains on the micromechanical component. Therefore, there is no need to worry about stability issues arising from the complete removal (undesirable or undefined) of at least one sacrificial layer 16 and 18 extending into at least one residual region 16a and 18a.

[0031] The etching medium used to perform method step S4 may be guided, for example, via at least one etching channel 40. The at least one etching channel 40 may be sealed (to complete method step S4) for example by means of at least one sealing layer 42 in a dielectric-sealed and / or air-sealed manner. The at least one sealing layer 42 may optionally be an electrically insulating layer (e.g., a silicon dioxide layer, a silicon nitride layer, a silicon-rich silicon nitride layer, a silicon carbide layer, and / or an alumina layer) and / or a conductive layer (e.g., a metal layer, a combination of metal layers) and / or a semiconductor layer (e.g., silicon, doped silicon, germanium, and / or doped germanium). Alternatively, a eutectic may be used to seal the at least one etching channel 40. In particular, gold-silicon eutectic, gold-germanium eutectic, eutectic containing gold, silicon, and germanium, aluminum-germanium eutectic, or eutectic containing aluminum and / or germanium and / or silicon and / or copper may be formed to seal the at least one etching channel 40. Similarly, a laser-seal-verfahren method can be implemented to seal at least one etched channel 40 using a molten material, such as a film material layer 38, at least one sacrificial layer 16 and 18, an electrode material layer 34, a substrate 22, intermediate layers 24 to 28 and / or at least one additional layer of molten material applied to the film material layer 38, such as a layer made of gold, germanium, aluminum, silicon and / or copper.

[0032] As an optional method step S5, at least one conductor track 44 having a diffusion barrier layer 46 may also be constructed on the micromechanical component and electrically contacted with the diaphragm material layer 38 at at least one location. Optionally, at least one conductor track 44 may be at least partially covered by a passivation layer 48 and at least partially situated on an electrically insulating layer (e.g., a sealing layer 42).

[0033] Figure 2 A schematic diagram showing a second embodiment of the micromechanical component is provided.

[0034] Unlike the aforementioned implementation methods, in Figure 2 In the micromechanical component, the electrode structure 12 is insulated from the diaphragm 10 by means of at least one insulating region 20b made of at least one electrically insulating material. This can be achieved by constructing the at least one insulating region 20b made of at least one electrically insulating material in accordance with the method step S2 of the aforementioned manufacturing method, such that the electrode structure 12 is electrically insulated from the (subsequent) diaphragm 10 by means of the at least one insulating region 20b. For the at least one insulating region 20b, silicon nitride, silicon-rich silicon nitride, silicon carbide, and / or alumina may also be used as at least one electrically insulating material.

[0035] As in Figure 2As can also be identified, an electrical "underground channel" 52 can be constructed on the micromechanical component by means of at least one conductor track 50 formed between the two insulating layers 24 and 26. With at least one electrical "underground channel" 52, the wiring path for contact can be more easily laid separately from at least one etched channel 40 and / or "electrical crossing" can be achieved. The orientation of the conductor track 50 between the two insulating layers 24 and 26 allows for etching of the insulating layer 24, which is also made of silicon oxide, during the removal of the sacrificial layers 16 and 18 made of silicon oxide, thus avoiding etching of the conductor track 50 in the cavity region. Electrical connections, such as to counter electrode 30a and / or reference counter electrode 30b, between conductor track 50 and at least one sub-region of wiring layer 28 can be achieved through contact holes within insulating layer 26. The construction of at least one electrical “underground channel” 52 (in optional method step S0) can thus help extend the lifespan of the micromechanical component and / or help simplify conductor track guidance and / or help increase its wiring complexity.

[0036] about Figure 2 For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0037] Figure 3a and Figure 3b A schematic diagram showing a third embodiment of the micromechanical component is shown.

[0038] exist Figure 3a and Figure 3b The micromechanical component schematically reproduced in the diagram not only has at least one residual region 16a and 18a for separating at least one sacrificial layer 16 and 18 from at least one insulating region 20a of cavity 14, but also has at least one insulating region 20b for electrically insulating electrode structure 12 from diaphragm 10. Furthermore, Figure 3a and Figure 3b The micromechanical component has at least one spring-shaped conductor track 54, via which the electrode structure 12 is electrically attached to at least one conductive member 56 formed of electrode material layer 34 on wiring layer 28. Thus, electrical contact of electrode structure 12 is possible despite the presence of at least one insulating region 20b (for electrically insulating electrode structure 12 from diaphragm 10). The at least one conductive member 56 formed of material layer 34 can, for example, be configured as at least one conductor track and / or at least one electrical contact portion to electrically contact wiring layer 28.

[0039] At least one spring-shaped conductor track 54 may be located "outside the electrode structure 12," i.e., attached to at least one outer surface of the electrode structure 12, and / or arranged "inside the electrode structure 12," i.e., within the volume surrounded by the electrode structure 12. Preferably, the electrode structure 12 may be electrically contacted via an even number of spring-shaped conductor tracks 54. Preferably, the spring-shaped conductor tracks 54 are configured to be mirror-symmetric about at least one mirror-symmetric plane intersecting the electrode structure 12 centrally, or point-symmetric about the center point of the electrode structure 12.

[0040] In addition, Figure 3a The electrical connection portion 58 of the diaphragm 10 and the electrical connection portion 60 of the wiring layer 28 are marked in the middle.

[0041] In addition to the electrode structure 12, at least one spring-shaped conductor track 54 may be formed by the electrode material layer 34 in method step S1 / sub-step S1b such that the electrode structure 12 is electrically attached to at least one conductive member 56 formed by the electrode material layer 34 on the wiring layer 28 via the at least one spring-shaped conductor track 54. Figure 3b As can be identified, at least one spring-shaped conductor track 54 can be constructed, for example, as a strip extending along the central axis. spring.

[0042] about Figure 3a and Figure 3b For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0043] Figure 4 and Figure 5 Schematic partial illustrations of the fourth and fifth embodiments of the micromechanical components are shown respectively.

[0044] As in Figure 4 and Figure 5 As can be identified separately, at least one spring-shaped conductor track 54 configured as a lath spring may also have a branch / fork at its end oriented away from the electrode structure 12. In this case, both ends of the branch / fork can be in electrical contact with the wiring layer 28 via each conductive member 56 formed of the electrode material layer 34. The branch / fork can be configured as a branch / fork perpendicular to the axis of the lath spring. Figure 4 The structure is configured as a branch / fork portion at an angle to the axis of the leaf spring. Figure 5 Alternatively, it can be configured as a branch / fork with rounded corners. Furthermore, at least one conductor track 54 can be attached to the electrode structure 12 via at least one torsion spring structure 57.

[0045] about Figure 4 and Figure 5 For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0046] Figure 6 and Figure 7 Schematic partial illustrations of the sixth and seventh embodiments of the micromechanical components are shown respectively.

[0047] As an alternative or supplement to at least one spring-shaped conductor track 54 constructed as a lath spring, at least one spring-shaped conductor track 54 may also be constructed in the form of a U-shaped spring. At least one U-shaped spring may each comprise two outer segments that run parallel to each other and an intermediate segment connecting the two outer segments. For example, two U-shaped springs can be constructed as spring-shaped conductor tracks 54 on two oppositely oriented sides of the electrode structure 12. Two U-shaped springs arranged on the same side of the electrode structure 12 may optionally be arranged such that their intermediate portions are oriented towards each other. Figure 6 ), or make their middle parts oriented away from each other ( Figure 7 Furthermore, the two parallel outer sections of at least one U-shaped spring can be of different lengths. Additionally, the intermediate section connecting the two outer sections can be of the same or different lengths from the strip-shaped section connecting the at least one U-shaped spring to the electrode structure 12. Furthermore, multiple U-shaped springs can be connected in series. In principle, it is possible to fix the spring structure at any point on the circumference of the electrode structure 12.

[0048] about Figure 6 and Figure 7 For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0049] Figure 8 A schematic partial illustration of the eighth embodiment of the micromechanical component is shown.

[0050] As an alternative or supplement to the aforementioned form of at least one spring-shaped conductor track 54, at least one spring-shaped conductor track 54 may also be constructed in the form of an O-shaped spring. At least one O-shaped spring may respectively comprise two outer segments 61a along the axial direction, two intermediate segments 61b perpendicular to the axial direction, and two intermediate segments 61c parallel to the axial direction, wherein the two intermediate segments 61b are connected to each other via each of the intermediate segments 61c, and each outer segment 61a is attached to the other intermediate segment 61b. Furthermore, all the forms of at least one spring-shaped conductor track 54 described above may extend into a groove 62 constructed on the electrode structure 12.

[0051] about Figure 8For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0052] Figures 9 to 11 Schematic partial illustrations of the ninth, tenth, and eleventh embodiments of the micromechanical components are shown respectively.

[0053] As in Figures 9 to 11 As can be identified, at least one spring-shaped conductor track 54 can also be arranged within the volume 64 surrounded by the electrode structure 12. This achieves a particularly space-saving arrangement of the at least one spring-shaped conductor track 54. All the forms described above for the at least one spring-shaped conductor track 54 can preferably be arranged in an even total, for example, as two U-shaped springs (…). Figure 10 ) or as four U-shaped springs ( Figure 9 The spring-shaped conductor tracks 54 are arranged within a volume 64 surrounded by the electrode structure 12. Regardless of the even total number, the spring-shaped conductor tracks 54 can be selectively configured to be mirror-symmetric about at least one mirror-symmetric plane intersecting the electrode structure 12. Figure 9 ) or constructed as a point-symmetric structure about the center point of electrode structure 12. Figure 10 Regardless of its shape and total number, the spring-shaped conductor track 54 may also surround the central contact region 66 extending into the volume 64, to which the spring-shaped conductor track 54 is mechanically or electrically attached,

[0054] exist Figure 11 In the example, each of the spring-shaped conductor tracks 54 is constructed in the form of a semi-circular track, wherein two spring-shaped conductor tracks 54, constructed in a mirror-symmetric manner about a plane intersecting the center of the electrode structure 12, surround the central contact region 66, and are mechanically attached to the central contact region and possibly also electrically attached. Instead of two spring-shaped conductor tracks 54 each in the form of a semi-circular track, four mirror-symmetric spring-shaped conductor tracks 54 may also be attached to and surround the central contact region 66 in the form of quarter-circular tracks.

[0055] about Figures 9 to 11 For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0056] Figure 12a and Figure 12b A schematic partial illustration of the twelfth embodiment of the micromechanical component is shown.

[0057] Such as using Figure 12b along Figure 12a As can be identified from the cross-section of line AA', at least one spring-shaped conductor track 54 has a spring thickness d perpendicular to the orientation of diaphragm 10.spring The minimum electrode thickness d, which can be less than the electrode structure 12 and perpendicular to the orientation of the diaphragm 10, is also possible. electrode At least one spring-shaped conductor track 54 has a spring thickness d oriented perpendicular to the diaphragm 10. spring The minimum electrode thickness d, which is smaller than the electrode structure 12 and perpendicular to the orientation of the diaphragm 10, is less than the minimum electrode thickness d. electrode The configuration is possible regardless of the shape of the corresponding spring-shaped conductor track 54, its total number, its mirror symmetry or point symmetry, and its arrangement "outside" and / or "inside" the electrode structure 12.

[0058] about Figure 12a and Figure 12b For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0059] Figure 13a and Figure 13b A schematic partial illustration of the thirteenth embodiment of the micromechanical component is shown.

[0060] Figure 13b Show along Figure 13a The cross-section of line BB'. Figure 13a and Figure 13b At least one spring-shaped conductor track 54 is also arranged within the volume 64 surrounded by the electrode structure 12. Regardless of the form, number, or mirror or point symmetry of the at least one spring-shaped conductor track 54, at least one reinforcing beam 68 protruding through the volume 64 may also span the at least one spring-shaped conductor track 54 on its oriented side toward the diaphragm 10. The at least one reinforcing beam 68 attached to the diaphragm may improve the stiffness of the diaphragm.

[0061] about Figure 13a and Figure 13b For further characteristics and features of the micromechanical components and manufacturing methods suitable for their fabrication, please refer to the foregoing embodiments.

[0062] All the examples described above for the spring-shaped conductor track 54 realize the feeding of a flexible electrical conductor track to the electrode structure 12.

[0063] In an alternative embodiment of the example described above, the residual regions 16a and 18a may also be made of silicon-rich silicon nitride, while the sacrificial layers 16 and 18 in the cavity region are made of silicon oxide. To achieve this, it is preferable to first deposit a sacrificial layer 16 made of silicon oxide, which is subsequently removed outside the cavity region, i.e., in the residual region 16a. Then, a silicon-rich silicon nitride layer is deposited from silicon oxide. If the CMP step is now performed such that the silicon-rich silicon nitride layer on the sacrificial layer 16 is removed in the cavity region, a sacrificial layer 16 made of silicon oxide is obtained in the cavity region, which is surrounded by the residual region 16a made of silicon-rich silicon nitride. Accordingly, the residual region 18a can be made of silicon-rich silicon nitride and the sacrificial layer 18 can be made of silicon oxide. Furthermore, an etch channel 40 filled with silicon oxide can also be created in this way, which is laterally bounded by silicon-rich silicon nitride, and through which an etch medium can be guided to remove the sacrificial layers 16 and 18 in the cavity region.

[0064] Furthermore, all of the aforementioned micromechanical components are advantageously applicable to sensor devices or microphone devices, particularly pressure sensors. In all of the aforementioned micromechanical components, the electrode structure 12 achieves good adjustability due to pressure changes on the outer / probe side of the diaphragm 10 oriented away from the inner diaphragm side 10a, or due to acoustic wave impacts on the outer / probe side of the diaphragm. The capacitance change at the measuring capacitance formed by the electrode structure 12 and the counter electrode 30a varies (almost) linearly with pressure changes or acoustic wave intensity.

Claims

1. A micromechanical component for a sensor device or microphone device, said micromechanical component having: A diaphragm (10) having an inner side (10a), wherein, The electrode structure (12) is at least partially attached directly or indirectly to the inner side (10a) of the diaphragm; and A cavity (14) is constructed in a volume exposed by at least one removal region of at least one sacrificial layer (16, 18), wherein the inner side (10a) of the diaphragm (10) is adjacent to the cavity (14), and an electrode structure (12) at least partially attached directly or indirectly to the inner side (10a) of the diaphragm is at least partially surrounded by the cavity (14), wherein at least one residual region (16a, 18a) made of at least one electrically insulating sacrificial layer material of the at least one sacrificial layer (16, 18) still exists on the micromechanical component; The feature is that at least one insulating region (20a, 20b) is made of at least one electrically insulating material different from the at least one electrically insulating sacrificial layer material, wherein, by means of the at least one insulating region (20a, 20b), the electrode structure (12) is electrically insulated from the diaphragm (10) and / or at least one residual region (16a, 18a) of the at least one sacrificial layer (16, 18) is separated from the cavity (14). The diaphragm (10) includes an etching channel (40) through which an etching medium for etching the sacrificial layer is guided, the etching channel being sealed after etching is completed.

2. The micromechanical component according to claim 1, wherein, The at least one residual region (16a, 18a) is composed of silicon dioxide or silicon-rich silicon nitride.

3. The micromechanical component according to claim 1 or 2, wherein, The at least one insulating region (20a, 20b) is composed of silicon nitride, silicon-rich silicon nitride, silicon carbide and / or aluminum oxide as the at least one electrical insulating material.

4. The micromechanical component according to any one of the preceding claims, wherein, At least one conductive component (56) is in electrical contact with a wiring layer (28), which serves as at least one intermediate layer (24, 26, 28) and at least partially covers the substrate surface (22a) of the substrate (22), wherein the electrode structure (12) is electrically attached to the at least one conductive component (56) via at least one spring-shaped conductor track (54), wherein the at least one conductive component (56), the at least one spring-shaped conductor track (54), and the electrode structure (12) are formed from a common electrode material layer (34).

5. A method for manufacturing a micromechanical component for a sensor device or microphone device, the method comprising the following steps: The volume of the subsequent cavity (14) of the subsequent micromechanical component is determined at least by forming at least one sacrificial layer (16, 18) made of at least one electrically insulating sacrificial layer material, wherein, The electrode structure (12) is formed by being at least partially surrounded by the volume of the subsequent cavity (14); A diaphragm (10) forming the subsequent micromechanical component, the diaphragm having an inner side (10a) defining the subsequent cavity (14), wherein the electrode structure (12) is at least partially directly or indirectly attached to the inner side (10a) of the diaphragm (S3), the diaphragm (10) having an etching channel (40) through the diaphragm (10) for guiding the etching medium for etching the sacrificial layer; and The cavity (14) of the subsequent micromechanical component is formed such that at least one region of the at least one sacrificial layer (16, 18) made of the at least one electrically insulating sacrificial layer material is removed, such that the inner side (10a) of the diaphragm (10) is adjacent to the cavity (14), and the electrode structure (12) at least partially attached directly or indirectly to the inner side (10a) of the diaphragm is at least partially surrounded by the cavity (14), wherein at least one residual region (16a, 18a) of the at least one sacrificial layer (16, 18) made of the at least one electrically insulating sacrificial layer material remains on the micromechanical component, the removal being achieved by etching with the aid of an etching medium, and the etched channel (40) being sealed after etching is completed; Its characteristics include the following steps: At least one insulating region (20a, 20b) is thus formed from at least one electrically insulating material different from the at least one electrically insulating sacrificial layer material, such that the electrode structure (12) is electrically insulated from the diaphragm (10) by means of the at least one insulating region (20a, 20b) and / or at least one residual region (16a, 18a) of the at least one sacrificial layer (16, 18) is separated from the cavity (14) (S2).

6. The manufacturing method according to claim 5, wherein, Removal of at least one region of at least one sacrificial layer (16, 18) made of at least one electrically insulating sacrificial layer material is achieved by etching the corresponding region of the at least one sacrificial layer (16, 18) with an etching medium, wherein the at least one electrically insulating material of the at least one insulating region (20a, 20b) has higher etch resistance than the at least one electrically insulating sacrificial layer material for the etching medium.

7. The manufacturing method according to claim 5 or 6, wherein, The at least one sacrificial layer (16, 18) is formed of silicon dioxide, which is the material of the at least one electrically insulating sacrificial layer.

8. The manufacturing method according to any one of claims 5 to 7, wherein, The at least one insulating region (20a, 20b) is formed of silicon nitride, silicon-rich silicon nitride, silicon carbide and / or aluminum oxide as the at least one electrical insulating material.

9. The manufacturing method according to any one of claims 5 to 8, wherein, In order to determine the volume of the subsequent cavity (14) and to form the electrode structure (12), the substrate surface (22a) of the substrate (22) and / or at least one intermediate layer (24, 26, 28) covering the substrate surface (22a) are covered as a first sacrificial layer (16) of the at least one sacrificial layer (16, 18) made of the at least one electrically insulating sacrificial layer material (S1a), the side of the first sacrificial layer (16) facing away from the substrate (22) is at least partially covered by an electrode material layer (34) such that the electrode structure (12) is formed by at least a sub-region of the electrode material layer (34) (S1b), and the side of the electrode material layer (34) facing away from the first sacrificial layer (16) is at least partially covered by a second sacrificial layer (18) of the at least one sacrificial layer (16, 18) made of the at least one electrically insulating sacrificial layer material (S1c).

10. The manufacturing method according to claim 9, wherein, At least one conductive component (56) is in electrical contact with a wiring layer (28) that serves as at least one intermediate layer (24, 26, 28) covering at least partially the substrate surface (22a), wherein, in addition to the electrode structure (12), the at least one conductive component (56) and a spring-shaped conductor track (54) are also formed from the electrode material layer (34), and the electrode structure (12) is electrically attached to the at least one conductive component (56) via the at least one spring-shaped conductor track (54); and / or The at least one insulating region includes an insulating region (20a) disposed on the electrode material layer (34) to separate the residual region (18a) of the second sacrificial layer (18) from the cavity (14).

11. The manufacturing method according to claim 10, wherein, A silicon dioxide layer (24) and a silicon-rich silicon nitride layer (26) are also formed between the wiring layer (28) and the substrate surface (22a) as at least one additional intermediate layer (24, 26, 28), wherein, adjacent to the subsequent cavity (14), at least one conductor track (50) is embedded between the silicon dioxide layer (24) and the silicon-rich silicon nitride layer (26), the at least one conductor track being partially electrically connected to the wiring layer (28) through an opening in the silicon-rich silicon nitride layer (26) and being able to extend beyond the cavity (14).

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