Microelectromechanical sensor component and microelectromechanical inertial sensor

Abstract

The invention relates to a microelectromechanical sensor component (1) comprising a substrate (2) with a substrate surface (2a), a seismic mass (4) connected to the substrate (2) and movable relative to the substrate (2) via a suspension spring (3), wherein the seismic mass (4) is deflectable in a deflection direction (A) perpendicular to the substrate surface (2a), and an evaluation electrode (5) arranged between the substrate (2) and the seismic mass (4) for capacitively detecting a deflection of the seismic mass (4) and providing a capacitive useful signal, wherein the microelectromechanical sensor component (1) further comprises a reference electrode (6) with several reference electrode sections (6a) forming a reference electrode frame (6b) that at least partially surrounds the seismic mass (4).wherein the reference electrode (6) is anchored to the substrate (2) by at least two attachment points (7) and a reference electrode section (6a) extends freely between each of the two attachment points (7), and comprises a reference counter electrode (9) arranged between the substrate (2) and the reference electrode (6) for providing a capacitive reference signal in conjunction with the reference electrode (6). The invention further relates to a microelectromechanical inertial sensor (20) with such a microelectromechanical sensor component (1).

Description

[0001] The invention relates to a microelectromechanical sensor component. The invention further relates to a microelectromechanical inertial sensor. State of the art

[0002] Microelectromechanical sensor components and microelectromechanical inertial sensors are known from the prior art. Microelectromechanical systems are also abbreviated as MEMS.

[0003] To detect accelerations, microelectromechanical sensor components can comprise a substrate and a seismic mass that can be deflected relative to the substrate. The deflection of this mass can be capacitively detected by means of an evaluation electrode. Depending on the design of the microelectromechanical sensor components, they can be configured to detect a deflection of the seismic mass parallel to a substrate surface and / or perpendicular to the substrate surface. Various measurement principles are known for detecting deflections of the seismic mass perpendicular to the substrate surface. These sensor components, also referred to as z-acceleration sensors (based on the three-dimensional spatial axis designations x, y, z), employ corresponding sensor components.For example, the seismic mass can be designed as a seesaw structure with asymmetrically shaped rocker arms and suspended by means of a torsion spring over two spaced-apart evaluation electrodes, which can capacitively detect a deflection of a rocker arm from a rest position. Furthermore, it is also known to arrange a seismic mass translationally movable over an evaluation electrode via suspension springs, such that the seismic mass, upon deflection, does not tilt but rather undergoes a translational displacement away from or towards the substrate surface. An example of such a sensor component with a translationally movable seismic mass perpendicular to the substrate surface can be found, for example, in US 6,892,576 B2.In order to enable a differential evaluation of the capacitance change associated with a translational displacement of the seismic mass, it may be provided that a so-called top electrode is arranged on a side of the seismic mass facing away from the evaluation electrode, or that a reference electrode is arranged between the substrate and a substantially immobile part of the seismic mass. Disclosure of the invention

[0004] According to the features of independent claim 1, a microelectromechanical sensor component is proposed, comprising a substrate with a substrate surface, a seismic mass connected to the substrate and movable relative to the substrate via a suspension spring, wherein the seismic mass is deflectable in a deflection direction perpendicular to the substrate surface, and an evaluation electrode arranged between the substrate and the seismic mass for capacitively detecting a deflection of the seismic mass and providing a capacitive useful signal, wherein the microelectromechanical sensor component further comprises a reference electrode with several reference electrode sections forming a reference electrode frame that at least partially surrounds the seismic mass.wherein the reference electrode is anchored to the substrate by at least two attachment points and a reference electrode section extends freely between each of the two attachment points, and wherein the microelectromechanical sensor component has a reference counter electrode arranged between the substrate and the reference electrode for providing a capacitive reference signal in conjunction with the reference electrode.

[0005] In simplified terms, it is proposed to surround the seismic mass for differential capacitive evaluation with a reference electrode on several, and in particular all, lateral sides. This aims to provide a particularly accurate reference signal, taking into account any mechanical stress effects on the sensor component during operation, and thereby ensuring high offset stability in signal evaluation. For example, mechanical stress on the sensor component can lead to local or widespread substrate deflection, which can cause a change in the basic distance between the evaluation electrode and the seismic mass. Such a change in distance can be associated with a corresponding offset of the useful signal from the evaluation electrode.If the seismic mass is surrounded by the reference electrode, substrate deflections also affect sections of the reference electrode in the affected areas, causing a corresponding change in the reference signal. This allows the offset of the useful signal to be compensated, at least approximately, by the change in the reference signal. Thus, the difference between the useful signal and the reference signal remains small when mechanical stress occurs, and the sensor component exhibits comparatively stable offsets. In other words, a local, stress-dependent adjustment of the reference electrode level can be achieved through mechanical interaction between the reference electrode and the substrate surface. By designing the reference electrode as a frame, the microelectromechanical sensor component can be made compact, while still effectively implementing the proposed method of influencing the differential capacitive evaluation.The reference electrode can be arranged in the same functional layer as the seismic mass, thereby reliably avoiding manufacturing-related offset effects, especially compared to a spaced top electrode.

[0006] A microelectromechanical sensor component can, for example, be a semiconductor-based component with mechanical and electrical microstructures. Due to its microstructural design, a microelectromechanical sensor component can be suitable for implementation as a system-on-chip (SoC). As a sensor component, the microelectromechanical sensor component can be configured to detect physical quantities. The sensor component described in this application can, in particular, be configured to detect translational acceleration as a physical quantity in a direction-dependent manner.

[0007] The substrate can be a planar semiconductor support structure. For example, the substrate can be a silicon wafer. The substrate has a substrate surface on one front side and a back side on the opposite rear side. The front side of the substrate can form an active side on which the mechanical and electrical microstructures of the sensor component are arranged.

[0008] The seismic mass is connected to the substrate and movable relative to the substrate via a suspension spring. A seismic mass can be a mechanical structure of the sensor component, designed to interact with the physical quantity to be detected, in particular acceleration force, and capable of causing a capacitive signal change at the evaluation electrode that is representative of the physical quantity. The seismic mass can be anchored to the substrate via one or more connection points. For example, the seismic mass can be deflected from a defined rest position, so that a relative deflection of the seismic mass from the rest position can be used to detect the physical quantity. The mobility of the seismic mass is achieved by one or, in particular, several suspension springs, whereby the degrees of freedom of the seismic mass can be predetermined by a suitable spring design.The suspension spring can be fixed at one end of the spring to a connection point between the seismic mass and the substrate, and at one end of the spring to the movable seismic mass.

[0009] The seismic mass can be deflected in a direction essentially perpendicular to the substrate surface. Put simply, the seismic mass can be designed to move towards and away from the substrate surface. In particular, the seismic mass can be deflected translationally in the aforementioned direction.

[0010] Compared to seesaw structures, translationally displaceable seismic masses are associated with reduced mechanical noise, also known as Brownian noise, because not only an asymmetric mass component, but the entire movable seismic mass contributes to the mechanical sensitivity of the microelectromechanical sensor component. Thus, a good signal-to-noise ratio can be achieved for the microelectromechanical sensor component using a translationally displaceable seismic mass.

[0011] The microelectromechanical sensor component further comprises an evaluation electrode arranged between the substrate and the seismic mass for capacitive detection of a displacement of the seismic mass and for providing a capacitive signal. The evaluation electrode can be an electrically conductive, stationary electrode element that is essentially immobilized and fixed to the substrate. The evaluation electrode can be spaced from the substrate and electrically insulated by an insulating layer, for example, an oxide layer. The evaluation electrode can be connected to an electrical conductor system of the microelectromechanical sensor component, which in turn can be electrically connected to an evaluation circuit. The evaluation electrode can, in particular, extend beneath a movable section of the seismic mass.The evaluation electrode can be arranged at a distance from the mechanical connection points of the seismic mass.

[0012] The microelectromechanical sensor component further comprises a reference electrode with several reference electrode sections. The reference electrode, in conjunction with the counter-reference electrode, provides a capacitive reference signal to enable the evaluation of the useful signal and the reference signal into a differential overall signal. Differential evaluation allows for a more precise measurement of the physical quantity, independent of, for example, fluctuating environmental conditions, manufacturing tolerances, and mechanical stress effects within the sensor component. The reference electrode is essentially rigid. In other words, the reference electrode does not deflect under an applied acceleration force. The reference electrode sections frame the seismic mass, at least partially, thus surrounding it on several, and in particular all, lateral sides of the seismic mass.A lateral side of the seismic mass can be understood as a side of the seismic mass that does not coincide with a bottom surface facing the substrate surface or a top surface facing away from the substrate surface, but rather is located on an outer surface connecting the top and bottom surfaces. The lateral surfaces of the seismic mass can, in particular, extend substantially perpendicular to the substrate surface. A reference electrode frame surrounding the seismic mass, at least in part, can be either continuous or interrupted, as will be explained further in connection with corresponding embodiments. The reference electrode is anchored to the substrate by at least two attachment points.By carefully selecting the number and placement of the reference electrode's attachment points, it can be ensured that mechanical stress affects changes in distance to the reference capacitance in a similar way to changes to the evaluation capacitance, i.e., below the seismic mass. Thus, the differential signal (the difference between the useful signal and the reference signal) remains small when mechanical stress occurs; in other words, the sensor is comparatively offset-stable. The attachment points can provide a local fixation of the reference electrode without any additional degrees of freedom, so that the reference electrode is rigidly connected to the substrate. In this context, a reference electrode section is defined as a region of the reference electrode that extends freely between two attachment points. Therefore, the reference electrode sections can be designed in a bridge-like manner.If substrate deflection occurs in a substrate region where a connection point is present, the deflection is transferred, at least approximately, to the unsupported portion of the reference electrode section. This can result in locally varying distances between the reference counter electrode and the reference electrode, leading to a change in the reference signal. This change in the reference signal can at least approximately compensate for changes in the useful signal caused by local changes in the distance between the seismic mass and the evaluation electrode due to substrate deflection. Since the reference electrode is predominantly unsupported above the substrate, substrate deflection due to mechanical stress will not only change the basic distance between the evaluation electrode and the seismic mass, but also, at least in some areas, the basic distance between the reference electrode and the reference counter electrode.Since the reference electrode surrounds the seismic mass in a frame-like manner, very different forms of substrate curvature can occur, for example, with respect to different directions and combinations thereof, as well as with respect to different orders of substrate curvature, such as quadratic or cubic, without resulting in significant offset changes. The effects of the substrate curvature can thus be compensated for with respect to an offset signal. The attachment points of the reference electrode can be selected to match the geometry of the seismic mass, a chip, and / or a housing used to implement the microelectromechanical component sensor.In principle, there is a high degree of design freedom in the choice of aspect ratio in the sense of a ratio between length and width of the reference electrode, as well as with regard to a position and number of mechanical connection points of the seismic mass, with regard to a geometry and number of suspension springs, and with regard to a size and position of the evaluation electrode.

[0013] The reference electrode can be an electrically conductive, stationary electrode element that is essentially fixed to the substrate. The reference electrode can be separated from the substrate and electrically insulated by an insulating layer, such as an oxide layer. The reference electrode can be connected to an electrical conductor system of the microelectromechanical sensor component, which in turn can be electrically connected to an evaluation circuit.

[0014] According to one embodiment, the reference electrode sections can be designed and arranged in the microelectromechanical sensor component such that a mean change in distance between the evaluation electrode and the seismic mass caused by mechanical stress in the sensor component, relative to a rest position of the seismic mass, corresponds to a mean change in distance between the reference counter electrode and the reference electrode with a maximum deviation of 25%. This allows for very good compensation of a stress-induced change in the useful signal by means of a corresponding change in the reference signal.In particular, the reference electrode sections can be designed and arranged in the microelectromechanical sensor component such that the mean change in distance between the evaluation electrode and the seismic mass corresponds to the mean change in distance between the reference counter electrode and the reference electrode, with a maximum deviation of 15%, and in particular 5%. Ideally, the mean change in distance between the evaluation electrode and the seismic mass and the mean change in distance between the reference counter electrode and the reference electrode can be identical. A mean change in distance can be calculated as the sum of the considered changes in distance along the evaluation electrode and the reference electrode, respectively, divided by the number of considered changes in distance.To achieve such ratios between mean distance changes, various component-specific parameters must be considered, for example, with regard to geometry, dimensions, material properties, conductor track system, chip, package and printed circuit board design, as well as other conditions and parameters influencing any mechanical stress on the sensor component, such as that of the microelectromechanical sensor component implemented in an inertial sensor. To determine a suitable design and arrangement of the reference electrode sections to achieve comparable mean distance changes in the areas of the seismic mass and the reference electrode, calculations, simulation models, or practical tests can be carried out based on the specific product specifications.

[0015] According to one embodiment, the reference electrode sections can extend parallel to the outer edges of the seismic mass. This allows mechanical stress effects along the seismic mass to affect the reference electrode in a comparable manner, so that reference signal changes can be obtained that essentially correspond to the actual useful signal changes. The outer edges of the seismic mass are defined as a lateral outer boundary of the seismic mass that can define a contour of the seismic mass, for example, a rectangular or square contour, in a plane parallel to the substrate surface.The parallel extension of the reference electrode sections can be understood, in particular, to mean that a respective longitudinal extension of the reference electrode sections, which may correspond to a maximum extension direction of a reference electrode section parallel to the substrate surface, runs parallel to an outer edge of the seismic mass. Furthermore, it can be provided, in particular, that the reference electrode sections run parallel to the nearest outer edge of the seismic mass at a predefined distance. Such a predefined distance can, for example, be smaller than the lateral extension of an associated reference electrode section that runs parallel to the substrate surface and perpendicular to the longitudinal extension.

[0016] According to one embodiment, the capacitively effective electrode area of ​​the reference electrode can correspond to the capacitively effective electrode area of ​​the evaluation electrode with a maximum deviation of 10%. In particular, the capacitively effective electrode area of ​​the reference electrode can correspond to the capacitively effective electrode area of ​​the evaluation electrode with a maximum deviation of 5%. Ideally, the capacitively effective electrode areas of the reference electrode and the evaluation electrode can be identical. This minimizes the offset of the overall signal resulting from the differential evaluation of the useful signal and the reference signal.In simplified terms, the aim is to achieve, through appropriate matching of the electrode areas, that in a rest position of the seismic mass, a measured reference signal value essentially corresponds to a measured useful signal value, so that ideally only one representative overall signal is obtained when the seismic mass is displaced. The capacitively effective electrode area of ​​the evaluation electrode can, in the case of multiple evaluation electrode sections, correspond to the sum of the individual capacitively effective electrode areas of the evaluation electrode sections. Similarly, the capacitively effective electrode area of ​​the reference electrode can correspond to the sum of the individual capacitively effective electrode areas of the reference electrode sections.

[0017] According to one embodiment, the reference electrode sections can form a continuous reference electrode frame. In other words, the reference electrode can surround the seismic mass without interruption. The reference electrode sections can therefore form a closed reference electrode frame. A continuous reference electrode frame has the advantages of simple manufacturing and a large reference electrode area for achieving a pronounced reference signal. Furthermore, a comparatively large component area, potentially subject to mechanical stress, can be used to influence the reference signal. According to one embodiment, the reference electrode sections can extend along the entire outer edge length of the seismic mass, parallel to the outer edges.

[0018] According to one embodiment, the reference electrode sections can form a sectionally interrupted reference electrode frame. In other words, the reference electrode can surround the seismic mass only in sections, with at least one interruption in the form of a free space between two reference electrode sections. The reference electrode sections can thus form an open reference electrode frame. A sectionally interrupted reference electrode frame can, for example, offer the advantage of a reduced effective electrode area if a comparatively small evaluation electrode is present and the capacitively effective electrode areas are to be matched as described above. Furthermore, a conductor feedthrough to the evaluation electrode without parasitic electrical capacitances can be enabled by an interruption in the reference electrode frame.Furthermore, the reference electrode sections are more mechanically decoupled from each other, so that stress effects caused by local bending of the reference electrode can be detected in a spatially limited area. According to one embodiment, the reference electrode sections can extend parallel to outer edge sections of the seismic mass, with unsupported outer edge sections provided without a parallel reference electrode section.

[0019] According to a further development, the interrupted reference electrode frame can have at least one interruption on a longitudinal side between two corner regions of the reference electrode frame. A corner region can be understood as a section of the reference electrode frame where a first part of a reference electrode section transitions at an angle, in particular at a right angle, into a second part of the reference electrode section, or where a first reference electrode section transitions at an angle, in particular at a right angle, into a second reference electrode section, wherein a connection point of the reference electrode is arranged between the first and the second reference electrode sections. The corner regions of the reference electrode frame can be connected to each other by straight longitudinal sides.If a break in the reference electrode frame is provided on such a longitudinal side, a conductor can be easily routed to the evaluation electrode without electrical parasitic capacitances. Furthermore, an angled reference electrode frame section can be provided between two breaks on different longitudinal sides. This angled section has two perpendicular main extension directions parallel to the substrate surface and can thus precisely respond to multidimensional mechanical stress effects, particularly substrate bending, by changing its distance. According to one embodiment, at least one break can be provided on each longitudinal side.

[0020] Alternatively or additionally, according to a further development, the interrupted reference electrode frame can have at least one interruption in a corner region. For example, a gap can be provided between two reference electrode sections that meet at right angles. In particular, the interruption can be so pronounced that the interrupted corner region of the reference electrode frame is eliminated entirely, thus completely eliminating any angled transition between reference electrode sections or between parts of a reference electrode section. According to one embodiment, at least one interruption can be provided at each corner region. If all corner regions of the reference electrode frame are eliminated in this way, only straight reference electrode sections are present along the longitudinal sides of the seismic mass.Such a geometrically simplified reference electrode frame is easy to manufacture and can, if desired, provide favorable mechanical decoupling of the reference electrode sections.

[0021] According to one embodiment, the reference electrode can have at least four attachment points. This ensures a particularly stable connection of the reference electrode to the substrate. With, for example, four or eight attachment points, favorable symmetry of the arrangement with respect to an x- and y-axis parallel to the substrate surface can be ensured. The attachment points can, for example, be evenly distributed over the reference electrode frame, so that the reference electrode sections extending between the attachment points can have the same capacitively effective individual electrode areas.

[0022] According to one embodiment, the reference electrode can have a maximum of eight attachment points. This ensures that a sufficient number of free-standing reference electrode sections with a capacitively effective reference electrode area are available and can be used to compensate for stress-induced changes in the signal at the evaluation electrode. The maximum of eight attachment points can be regularly distributed. In particular, if the seismic mass has a rectangular or square base shape, two attachment points of the reference electrode can be provided on each longitudinal side of the seismic mass.The two attachment points on each longitudinal side can divide the reference electrode frame into three equal sections along its length, or they can be positioned closer to the center of the reference electrode, which extends particularly parallel to the outer edge of the seismic mass, such that a central section is smaller than the two outer sections of the reference electrode. With such an arrangement, changes in distance at the corners of the reference electrode frame can be smaller in the event of substrate curvature than with an arrangement where each attachment point is located centrally on the longitudinal side, since the change in distance increases with increasing lateral distance to the attachment points.Depending on the specific design of the microelectromechanical sensor component with regard to material, geometry and dimensioning of the sensor component structures, as well as depending on the environment of the sensor component, for example a chip, package or printed circuit board, different compensation effects can be specifically set by varying the placement of the connection points.

[0023] According to one embodiment, the reference electrode can have at most two connection points. This provides a reference electrode with a particularly large capacitively effective reference electrode area, enabling a pronounced reference signal. Furthermore, by matching the capacitively effective electrode areas of the reference electrode and the evaluation electrode, the evaluation electrode can also be designed with a correspondingly large area to obtain a pronounced useful signal. A reference electrode with two connection points can be advantageous, for example, if the sensor component and / or a chip on which the sensor component is mounted, and / or a housing in which the sensor component is installed, has an elongated shape, since significantly different stress-induced effects can then occur in the x-axis direction than perpendicular to it in the y-axis direction.

[0024] According to one embodiment, at least one attachment point can be arranged in a corner region of the reference electrode frame. This allows for the creation of a stable reference electrode frame with favorable mechanical interaction with the substrate surface for local stress-dependent adjustment of the reference electrode level. According to one embodiment, an attachment point can be provided in each corner region of the reference electrode frame.

[0025] According to one embodiment, at least one attachment point can be arranged on a longitudinal side between two corner regions of the reference electrode frame. This allows, for example, a focus to be placed on angled reference electrode sections in order to better represent multidimensional stress or bending effects with the mechanically reacting reference electrode sections. Furthermore, the manufacture of such an attachment point can be simplified, since it is not necessary to ensure a particularly precise arrangement of the attachment point in an angled corner region.

[0026] According to one embodiment, the evaluation electrode can have a regular cross shape. For example, the evaluation electrode can have four symmetrically arranged cross arms. The cross arms can extend between mechanical connection points that anchor the seismic mass to the substrate. The cross arms can extend, for example, to connection points of the reference electrode frame. The evaluation electrode can be oriented centrally below a movable section of the seismic mass. The cross shape can be point-symmetric and / or axis-symmetric.With an evaluation electrode having a regular cross shape, a microelectromechanical sensor component with a metrologically favorable electrode shape can be provided, which enables uniform detection of a deflection of the seismic mass in different spatial directions and whose capacitively effective electrode area can be easily tuned to a capacitively effective electrode area of ​​the reference electrode.

[0027] According to a further development, the evaluation electrode can have an extension section shaped to fit the regular cross form. For example, a cross arm can transition into a transverse arm at its end furthest from the center of the cross. The evaluation electrode can be symmetrical with respect to the extension section, for example, by having two opposing cross arms with congruently shaped transverse arms such that the geometric shape of the evaluation electrode can be divided into two congruent mirror images along an axis of symmetry passing through the center of the cross. An extension section allows the capacitively effective electrode area of ​​the evaluation electrode to be easily adapted to the capacitively effective electrode area of ​​the reference electrode.Furthermore, a more pronounced signal can be achieved with a larger electrode area compared to the cross-shaped configuration, while still utilizing the available space. This is particularly relevant when mechanical connection points of the seismic mass obstruct the spread of the cross arms. Additionally, an extension section allows for the advantageous capacitive monitoring of elongated seismic masses with a rectangular base shape and a greater length than width.

[0028] According to one embodiment, the seismic mass can have at least two recesses, with at least one connection point of the reference electrode being arranged in each recess. Accordingly, the connection points of the reference electrode can be spatially located in an inner region of the seismic mass via connection arms extending from the reference electrode frame towards a geometric center of the seismic mass. The recesses in the seismic mass allow it to be subdivided into movable mass wings extending from a geometric center of the seismic mass between the recesses. The evaluation electrode can have a basic shape adapted to such mass wings, for example, cross-shaped arms with arm diameters that widen outwards towards the reference electrode frame.The seismic mass can be connected to the substrate via a connection point at its geometric center and suspension springs extending from this point. The proposed arrangement allows for a compact, centered mechanical connection of the seismic mass and the reference electrode, with high mobility of the seismic mass and a protected arrangement of the anchoring connection points.

[0029] According to one embodiment, the suspension spring can be designed such that the seismic mass can be deflected in directions perpendicular and parallel to the substrate surface, wherein the microelectromechanical sensor component has at least one lateral sensing element for detecting a deflection of the seismic mass parallel to the substrate surface. A lateral sensing element can be understood to be, for example, a capacitively acting sensing structure that, unlike a change in distance between the seismic mass and the evaluation electrode, can detect a lateral deflection of the seismic mass from a rest position.By appropriately designing the suspension spring, for example by using a specific spring shape to achieve a targeted reduction in spring stiffness in a given spatial direction for a corresponding deflection of the seismic mass along the given spatial direction, the degrees of freedom of the seismic mass can be precisely defined.

[0030] According to a further development, the seismic mass can be deflected in three mutually perpendicular spatial directions, wherein the microelectromechanical sensor component has at least two lateral sensing elements configured to detect a deflection of the seismic mass along two mutually perpendicular spatial directions parallel to the substrate surface. This advantageously expands the application range of the sensor component and increases the functional density on the claimed chip area in a system-on-chip implementation of the sensor component. Accordingly, the microelectromechanical sensor component can be configured to capacitively detect accelerations in all three-dimensional spatial axes. By means of suitable spring geometries and by adding lateral sensing elements for detection along an x-axis and a y-axis, the sensor component can thus be extended to a triaxial sensor component.This is particularly advantageous because the seismic mass simultaneously reduces mechanical noise in all three spatial directions. Compared to a side-by-side arrangement of three single-axis sensor elements on a chip, the same noise performance can thus be achieved in a significantly smaller area, or, assuming the same total area, a significantly better noise performance.

[0031] According to one embodiment, at least one lateral sensing element can have an electrode comb structure formed by mass electrode fingers arranged on the seismic mass and counter electrode fingers arranged parallel to the mass electrode fingers on the substrate. In particular, all lateral sensing elements can have such an electrode comb structure. With an electrode comb structure in which the mass electrode fingers and counter electrode fingers engage in the spaces between the other electrode fingers in a comb-like manner, a simple lateral sensing element suitable for the precise detection of a lateral deflection movement can be realized.

[0032] The invention also relates to a microelectromechanical inertial sensor comprising a microelectromechanical sensor component according to one of the features described above and a signal processing unit for applying and processing signals from the microelectromechanical sensor component. The microelectromechanical inertial sensor also offers the advantages described above of a compact design, high offset stability, and an improved signal-to-noise ratio. The microelectromechanical inertial sensor can be configured as an accelerometer for detecting translational acceleration and, for example, can be additionally configured as a rotational acceleration sensor by combining the microelectromechanical sensor component described above with a gyroscope component.The microelectromechanical inertial sensor can be configured, in particular, to detect acceleration in a vertical spatial direction with a displacement of the seismic mass perpendicular to the substrate surface. Due to the high offset stability of the microelectromechanical sensor component, an inertial sensor with high measurement accuracy and high measurement sensitivity can be realized according to the proposed features. A signal processing unit can include an evaluation circuit, which can be implemented as an integrated circuit, for example, as an ASIC (application-specific integrated circuit). The signal processing unit is configured to generate and / or process signals from the microelectromechanical sensor component and can, for example, receive and evaluate sensor signals from the microelectromechanical sensor component and perform control tasks.

[0033] The microelectromechanical sensor component can advantageously be integrated with, for example, a three-axis gyroscope and / or other, particularly three-axis, accelerometers on a common MEMS chip, in a common package, or in a common end device. In particular, the microelectromechanical sensor component, the gyroscope, and / or the additional accelerometer can be integrated on one and the same chip, since, unlike rocker-type designs, very small electrode gaps are not required to achieve very low noise levels. Therefore, the same electrode gaps can be used in the microelectromechanical sensor component as in the gyroscope and / or the additional accelerometers.This facilitates process integration, as realizing electrode gaps of different sizes can mean a significant increase in effort in the manufacturing of the inertial sensor.

[0034] According to one embodiment, the microelectromechanical inertial sensor can be configured for the detection of structure-borne sound, particularly bone conduction, and / or airborne sound. Due to its high measurement sensitivity and compact design, even very weak sound waves can be reliably detected by the inertial sensor. In particular, the microelectromechanical sensor component of the inertial sensor can be configured for bone conduction detection. By designing the sensor component with the proposed features and according to the optional embodiments, a particularly offset-stable and low-noise bone conduction detector can be provided. Due to its compact design and high measurement sensitivity, the microelectromechanical inertial sensor is advantageously suited for close-to-the-body application, thus enabling comfortable and reliable bone conduction detection.Such bone conduction detection can be advantageously used, for example, in modern wireless earphones or headsets. The signals from the bone conduction-detecting sensor component can be combined with simultaneously recorded microphone signals, for instance, to enable active noise cancellation. If the microelectromechanical sensor component is used in combination with other sensor elements, the aforementioned sensor component can serve as the bone conduction sensor, while the other sensor element can be used for activity detection or rotation rate detection, for example, for 3D audio applications.

[0035] The use of the aforementioned microelectromechanical sensor component and / or the inertial sensor can be particularly advantageous when noise reduction is a top priority for a z-accelerometer. The microelectromechanical sensor component with the aforementioned features can ensure a very good signal-to-noise ratio while simultaneously offering favorable offset performance.

[0036] The described microelectromechanical sensor component and / or the described microelectromechanical inertial sensor can be used, for example, in the automotive and / or consumer sector, such as in miniaturized hearables like earphones, earbuds or true wireless stereo headsets.

[0037] The described microelectromechanical sensor component and / or the described microelectromechanical inertial sensor can be used, for example, in connection with smartphones and tablets, wearables, hearables, smart glasses, smart contact lenses, augmented reality, virtual reality, drones, gaming, toys, robots, smart homes, and, for example, in industrial contexts for the following additional applications: wake-up functions for selected device modules, detection of device orientation, screen orientation and display orientation, detection of significant movement, shock and free-fall detection; HMI (human-machine interface) functionality, e.g.Multi-tap recognition, activity, gesture and context recognition, bone conduction detection, user recognition, voice recognition, keyword recognition; motion control, gimbal system, altitude and attitude stabilization, flight control, image stabilization, indoor and outdoor navigation, floor detection, position tracking and route recording, PDR (pedestrian dead reckoning), dynamic route planning, boundary and obstacle detection, indoor SLAM (simultaneous localization and mapping); intrusion monitoring, real-time motion detection and tracking, activity tracking, pedometer, calorie counter, sleep monitoring; hearable status detection (in-ear / out-of-ear detection), head orientation and movement determination; logistics, part tracking, energy management and energy-saving measurement, predictive maintenance; sensor data fusion.

[0038] The invention can also be used in connection with automotive applications, e.g., regarding: crash detection, e.g., in airbag systems; Electronic Stability Program (ESP), Vehicle Dynamics Control (VDC); hill start assist, hill hold control (prevention of rolling backward when starting on inclines); adaptive chassis control; smart tires, e.g., road condition monitoring, road noise cancellation; navigation applications; autonomous driving; theft detection, alarm functions; tailgate tilt control; optimization of engine control and the combustion process in gasoline or diesel engines.

[0039] The described microelectromechanical sensor component and / or the described microelectromechanical inertial sensor may be suitable for mass production in a semiconductor manufacturing process due to their fundamentally simple structure.

[0040] In general, in connection with this application, the words "ein / eine" are not to be understood as numerals, unless expressly defined otherwise, but as indefinite articles with the meaning of "at least one".

[0041] The invention allows for various embodiments and is explained in more detail below with reference to exemplary embodiments and the accompanying drawings. These show, in schematic form: Fig. 1 - a schematic diagram of a microelectromechanical sensor component according to a first embodiment in a top view; Fig. 2a) - the microelectromechanical sensor component according to the first embodiment in an initial state in a lateral sectional view along the section line AB; Fig. 2b) - a schematic diagram of the microelectromechanical sensor component according to the first embodiment in a stressed state in a lateral sectional view along the section line AB; Fig. 3 - a schematic diagram of the microelectromechanical sensor component according to the first embodiment in an initial state in a lateral sectional view along the section line CD; Fig. 4 - a schematic diagram of a microelectromechanical sensor component according to a second embodiment in a top view; Fig. 5 - a schematic diagram of a microelectromechanical sensor component according to a third embodiment in a top view; Fig. 6 - a schematic diagram of a microelectromechanical sensor component according to a fourth embodiment in a top view; Fig. 7 - a schematic diagram of a microelectromechanical sensor component according to a fifth embodiment in a top view; Fig. 8 - a schematic diagram of a microelectromechanical sensor component according to a sixth embodiment in a top view; Fig. 9 - a schematic diagram of a microelectromechanical sensor component according to a seventh embodiment in a top view; Fig. 10 - a schematic diagram of a microelectromechanical inertial sensor with a microelectromechanical sensor component.

[0042] The Fig. 1, Fig. 2a), Fig. 2b) and Fig. Figure 3 shows a microelectromechanical sensor component 1 in schematic diagrams, including top and side sectional views. According to the illustrated embodiments, the microelectromechanical sensor component 1 is configured as an acceleration sensor component.

[0043] The microelectromechanical sensor component 1 has a substrate 2, for example a silicon wafer, with a substrate surface 2a. Fig. 2a) shows the sensor component 1 in an initial state in which, ideally, no mechanical stress effects are present on the sensor component 1. Fig. Figure 2b) shows the sensor component 1 in a stressed state, where mechanical stress on the sensor component 1 causes a curvature of the substrate surface 2a. The associated effects on the sensor component 1 are explained in more detail below.

[0044] The microelectromechanical sensor component 1 has a seismic mass 4 connected to the substrate 2 and movable relative to the substrate 2 via suspension springs 3. The seismic mass 4 can be deflected translationally along a z-axis of a three-dimensional spatial coordinate system in a deflection direction A perpendicular to the substrate surface 2a, as shown in the Fig. 2a), Fig. 2b) and Fig. 3 is extractable. The seismic mass 4 is according to the in Fig. In the embodiment shown in Figure 1, the components are connected to the substrate 2 via four mechanical connection points 8, thus achieving favorable symmetry of the arrangement with respect to the x- and y-axes. The suspension springs 3 are each connected at one end to a mechanical connection point 8 and at the other end to the movable seismic mass 4. The seismic mass 4 may have perforations (not shown) to provide etching access for a manufacturing-related etching process and / or to selectively influence the damping properties of the microelectromechanical sensor component 1.

[0045] An evaluation electrode 5 is arranged between the substrate 2 and the seismic mass 4. This electrode serves to capacitively detect the displacement of the seismic mass 4 and to provide a capacitive signal from the detected displacement. The evaluation electrode 5 has a regular cross shape 5a and is arranged centrally beneath the movable seismic mass 4. The arms of the evaluation electrode 5 are spaced apart from the mechanical connection points 8 of the seismic mass 4 and extend to the connection points 7 of a reference electrode frame 6b, which are described below.

[0046] Furthermore, the microelectromechanical sensor component 1 has a substantially stationary reference electrode 6. The reference electrode 6 has several reference electrode sections 6a, which form a reference electrode frame 6b that at least surrounds the seismic mass 4, wherein the Fig. The reference electrode frame 6b shown in Figure 1 is designed as a continuous reference electrode frame 6b, such that a large electrode area E R is provided and mechanical stress effects are effective over a large electrode range. As further explained in Fig. As can be seen in Figure 1, the reference electrode sections 6a extend parallel to the lateral outer edges 4a of the seismic mass 4, thus surrounding it on its lateral sides. The reference electrode 6 is as shown in Figure 1. Fig. Figure 1 shows a total of four attachment points 7 anchored to the substrate 2. A reference electrode section 6a extends freely between each of the attachment points 7. The attachment points 7 are each arranged on a longitudinal side 6d between two corner regions 6c of the reference electrode frame 6b. Fig. Figure 3 shows from a lateral sectional view that the attachment points 7 are designed for the local anchoring of the reference electrode 6 to the substrate 2.

[0047] Furthermore, the microelectromechanical sensor component 1 has a reference counter electrode 9 arranged between the substrate 2 and the reference electrode 6 for providing a capacitive reference signal in conjunction with the reference electrode 6. As described in the Fig. 2a) and Fig. As can be seen in Figure 2b), the evaluation electrode 5 and the reference counter electrode 9 are insulated from the substrate 2 by an oxide layer 23. The evaluation electrode 5 and the reference counter electrode 9 are connected to an electrical conductor system of the microelectromechanical sensor component 1 (not shown in detail).

[0048] A reference signal can be provided by a frame-shaped reference electrode 6 surrounding the seismic mass 4. This signal allows mechanical stress effects, such as substrate bending, to be incorporated into the reference signal. As a result, changes in distance Δd1 induced by these stress effects between the seismic mass 4 (relative to its rest position) and the evaluation electrode 5 are at least similar to those between the reference electrode 6 and the counter-reference electrode 9. This allows stress-induced offset signals to be compensated for or at least reduced during differential capacitive evaluation, resulting in a comparatively offset-stable microelectromechanical sensor component 1. Furthermore, due to the translational deflection of the seismic mass 4, the microelectromechanical sensor component 1 exhibits lower mechanical noise than, for example, sensor structures with a rocker design.Furthermore, the frame-shaped arrangement of the reference electrode 6 provides a compact microelectromechanical sensor component 1 that is comparatively flat compared to sensor structures with a top electrode, enabling differential capacitive evaluation.

[0049] Based on the Fig. 2a) and Fig. 2b) schematically illustrates the effects of substrate bending due to mechanical stress on the component structures of the microelectromechanical sensor component 1. Fig. 2a) It is evident that in an initial state in which there is no substrate bending, there is a basic distance d1 between the evaluation electrode 5 and the seismic mass 4 in a rest position, as well as a basic distance d2 between the reference counter electrode 9 and the reference electrode 6. Fig. 2b) It is evident that a mechanical stress S can cause a curvature of the substrate 2, leading to locally varying changes in the distance Δd1 between the evaluation electrode 5 and the seismic mass 4 in its rest position. Because the reference electrode 6 surrounds the seismic mass 4 in a frame-like manner, locally varying changes in the distance Δd2 between the reference counter electrode 9 and the reference electrode 6 also occur in the areas of the reference electrode 6, so that a stress-induced offset of the useful signal of the evaluation electrode 5 and the reference signal of the reference counter electrode 9 can be advantageously compensated for by the altered reference signal.The reference electrode sections 6a can be designed and arranged such that a mean change in distance Δd1 between the evaluation electrode 5 and the seismic mass 4, caused by the mechanical stress S in the sensor component 1 and relative to a rest position of the seismic mass 4, corresponds to a mean change in distance Δd2 between the reference counter electrode 9 and the reference electrode 6 with a maximum deviation of 25%. The deviation can, in particular, be a maximum of 15% or a maximum of 5%. This allows for very good compensation of a stress-induced change in the useful signal by means of a corresponding change in the reference signal. A mean change in distance Δd1, Δd2 can each correspond to the sum of the considered changes in distance Δd1, Δd2 along the evaluation electrode 5 and the reference electrode 6 divided by the number of considered changes in distance Δd1, Δd2.

[0050] As in Fig. As can be seen in Figure 1, the reference electrode 6 has a capacitively effective electrode area E R on, which result from the sum of the individual electrode areas E R the reference electrode sections 6a. Furthermore, the evaluation electrode 5 has a capacitively effective electrode area E. A on, which here is referred to as the contiguous electrode surface E A is shown. Advantageously, the capacitively effective electrode area E can be R the reference electrode 6 of the capacitively effective electrode area E A The evaluation electrode 5 must have a maximum deviation of 10%. The deviation can be a maximum of 5%. Are the electrode surfaces E A , E RBy matching the area, the useful signal value can correspond to the reference signal value, so that in the differential evaluation a total signal is obtained that directly represents a displacement of the seismic mass 4.

[0051] In Fig. Figure 4 shows a microelectromechanical sensor component 1 according to a second embodiment. In this embodiment, a total of eight attachment points 7 are provided for anchoring the reference electrode 6 to the substrate 2. Two attachment points 7 are provided on each longitudinal side 6d of the seismic mass 4. The two attachment points 7 are arranged closer to a geometric center of the longitudinal sides 6d than to the corner regions 6c, so that a central reference electrode section 6a is smaller than the outer reference electrode sections 6a. This allows the changes in distance Δd2 in the corner regions 6c of the reference electrode frame 6b to be smaller in the event of substrate curvature than in an arrangement with one attachment point 7 located centrally on each longitudinal side 6c, since the change in distance Δd2 increases with increasing lateral distance to the attachment points 7.

[0052] In Fig. Figure 5 shows a microelectromechanical sensor component 1 according to a third embodiment. In this embodiment, a total of four attachment points 7 are provided for anchoring the reference electrode 6 to the substrate 2, wherein the attachment points 7 differ from those in Fig. In the first embodiment shown in Figure 1, the reference electrodes are arranged in the corner regions 6c of the reference electrode frame 6b. This provides a stable reference electrode frame 6b with favorable mechanical interaction with the substrate surface 2a.

[0053] In Fig. Figure 6 shows a microelectromechanical sensor component 1 according to a fourth embodiment. In this embodiment, a total of two attachment points 7 are provided for anchoring the reference electrode 6 to the substrate 2. This allows for a large electrode area E. RA very pronounced reference signal is obtained. Furthermore, the evaluation electrode 5 has an extension section 5b shaped to the regular cross shape 5a. Due to the modified shape of the evaluation electrode 5, larger changes in the useful signal will occur if the substrate 2 is strongly bent at the upper or lower edge shown in the image. This can now be better compensated for by also subjecting the reference electrode 6 to larger changes in distance Δd2 when substrate curvature occurs. This can be achieved by the more exposed electrode area E. R The reference electrode 6 with the two lateral attachment points 7 can be achieved. Reference electrodes 6 with only two attachment points 7 can be advantageously used in elongated sensor components 1, chips or housings, since significantly different stress-induced effects can then occur in the direction of the x-axis than perpendicular to it in the direction of the y-axis.

[0054] In Fig. Figure 7 shows a microelectromechanical sensor component 1 according to a fifth embodiment. In this embodiment, the reference electrode sections 6a form a sectionally interrupted reference electrode frame 6b, which has an interruption 10 on each longitudinal side 6d between the corner regions 6c of the reference electrode frame 6b. The interruption 10 allows, for example, conductor tracks without parasitic capacitances to be routed to the evaluation electrode 5. The angled reference electrode frame sections also allow for the reliable consideration of multidimensional mechanical stress effects. It is also conceivable, although not shown in detail, that an interrupted reference electrode frame 6b has at least one interruption 10 in a corner region of the reference electrode frame 6b.

[0055] In Fig. Figure 8 shows a microelectromechanical sensor component 1 according to a sixth embodiment. In this embodiment, the seismic mass 4 has several recesses 4b, a total of four according to the illustrated embodiment, with a connection point 7 of the reference electrode 6 arranged in each recess 4b of the seismic mass 4. The connection points 7 are located in an inner region of the seismic mass 4 via connecting arms 7b extending from the reference electrode frame 6b towards a geometric center of the seismic mass 4. The seismic mass 4 is divided into movable mass wings by the recesses 4b, which extend between the recesses 4b. The evaluation electrode 5 has a basic shape adapted to this, in that the cross arms have arm diameters that widen outwards in the direction of the reference electrode frame 6b.The seismic mass 4 is connected to the substrate 2 via a single mechanical connection point 8, which is located at a geometric center of the seismic mass 4, and suspension springs 3 extending from this point. A compact, centered mechanical connection between the seismic mass 4 and the reference electrode 6 can be achieved using a sensor component 1 according to the sixth embodiment.

[0056] In Fig. Figure 9 shows a microelectromechanical sensor component 1 according to a seventh embodiment. In this embodiment, the suspension spring 3 is designed such that the seismic mass 4 can be deflected in deflection directions A perpendicular and parallel to the substrate surface 2a. Furthermore, the microelectromechanical sensor component 1, according to the illustrated embodiment, has four lateral sensing elements 11 for detecting a deflection of the seismic mass 4 parallel to the substrate surface 2a. Overall, the seismic mass 4, according to the embodiment shown, is Fig. In the embodiment shown in Figure 9, the seismic mass 4 can be deflected in three mutually perpendicular spatial directions x, y, z, and the lateral sensing elements 11 are configured to detect a deflection of the seismic mass 4 along two mutually perpendicular spatial directions x, y parallel to the substrate surface 2a. This makes the microelectromechanical sensor component 1 a triaxial accelerometer. In this way, the seismic mass 4 can simultaneously reduce mechanical noise in all three spatial directions x, y, z. As shown in Fig. As schematically indicated in Figure 9, the lateral sensing elements 11 each have an electrode comb structure formed by mass electrode fingers 11b arranged on the seismic mass 4 and counter electrode fingers 11c arranged parallel to the mass electrode fingers 11b on the substrate 2, so that precise detection of lateral deflection movements is made possible in a simple way.

[0057] Fig.Figure 10 shows a schematic diagram of a microelectromechanical inertial sensor 20 with a microelectromechanical sensor component 1, which is connected via a signal link 22 to a signal processing unit 21, for example implemented as an ASIC, for generating and processing signals from the microelectromechanical sensor component 1. The microelectromechanical sensor component 1 can be configured, for example, according to one of the embodiments described above. The microelectromechanical inertial sensor 20 can, for example, be configured as an accelerometer for detecting translational acceleration. The microelectromechanical inertial sensor 20 can be configured for detecting structure-borne sound and / or airborne sound, in particular for detecting bone conduction sound.The microelectromechanical inertial sensor 20, due to the implemented microelectromechanical sensor component 1 according to the described features, results in an inertial sensor 20 characterized by high offset stability and a favorable signal-to-noise ratio. Its compact design and high sensitivity enable reliable and convenient sound detection, for example in wireless earphones or headsets. QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] US 6,892,576 B2

[0003]

Claims

[1] Microelectromechanical sensor component (1) comprising: - a substrate (2) with a substrate surface (2a); - a seismic mass (4) connected to the substrate (2) and movable relative to the substrate (2) via a suspension spring (3), wherein the seismic mass (4) is deflectable in a deflection direction (A) perpendicular to the substrate surface (2a); and - an evaluation electrode (5) arranged between the substrate (2) and the seismic mass (4) for capacitive detection of a displacement of the seismic mass (4) and provision of a capacitive useful signal; wherein the microelectromechanical sensor component (1) further comprises: - a reference electrode (6) with several reference electrode sections (6a) forming a reference electrode frame (6b) that at least partially surrounds the seismic mass (4), wherein the reference electrode (6) is anchored to the substrate (2) by at least two attachment points (7) and each reference electrode section (6a) extends freely between two attachment points (7); and - a reference counter electrode (9) arranged between the substrate (2) and the reference electrode (6) to provide a capacitive reference signal in conjunction with the reference electrode (6). [2] Microelectromechanical sensor component (1) according to claim 1, wherein the reference electrode sections (6a) are designed and arranged in the microelectromechanical sensor component (1) such that a mean change in distance (Δd1) between the evaluation electrode (5) and the seismic mass (4) caused by mechanical stress (S) in the sensor component (1) corresponds to a mean change in distance (Δd2) between the reference counter electrode (9) and the reference electrode (6) with a maximum deviation of 25%. [3] Microelectromechanical sensor component (1) according to claim 1 or 2, wherein the reference electrode sections (6a) extend parallel to outer edges (4a) of the seismic mass (4). [4] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein a capacitively active electrode area (E) R) the reference electrode (6) of a capacitively effective electrode area (E A ) the evaluation electrode (5) with a maximum deviation of 10%. [5] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein the reference electrode sections (6a) form a continuous reference electrode frame (6b). [6] Microelectromechanical sensor component (1) according to one of claims 1 to 4, wherein the reference electrode sections (6a) form a sectionally interrupted reference electrode frame (6b). [7] Microelectromechanical sensor component (1) according to claim 6, wherein the interrupted reference electrode frame (6b) has at least one interruption (10) on a longitudinal side (6d) between two corner regions (6c) of the reference electrode frame (6b). [8] Microelectromechanical sensor component (1) according to claim 6 or 7, wherein the interrupted reference electrode frame (6b) has at least one interruption (10) in a corner region (6c) of the reference electrode frame (6b). [9] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein the reference electrode (6) has at least four attachment points (7). [10] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein the reference electrode (6) has at most eight attachment points (7). [11] Microelectromechanical sensor component (1) according to any one of claims 1 to 8, wherein the reference electrode (6) has at most two attachment points (7). [12] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein at least one attachment point (7) is arranged in a corner region (6c) of the reference electrode frame (6b). [13] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein at least one attachment point (7) is arranged on a longitudinal side (6d) between two corner regions (6c) of the reference electrode frame (6b). [14] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein the evaluation electrode (5) has a regular cross shape (5a). [15] Microelectromechanical sensor component (1) according to claim 14, wherein the evaluation electrode (5) has an extension section (5b) molded onto the regular cross shape (5a). [16] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein the seismic mass (4) has at least two recesses (4b) and wherein at least one attachment point (7) of the reference electrode (6) is arranged in each recess (4b) of the seismic mass (4). [17] Microelectromechanical sensor component (1) according to one of the preceding claims, wherein the suspension spring (3) is designed such that the seismic mass (4) can be deflected in deflection directions (A) perpendicular and parallel to the substrate surface (2a), and wherein the microelectromechanical sensor component (1) has at least one lateral sensing element (11) for detecting a deflection of the seismic mass (4) parallel to the substrate surface (2a). [18] Microelectromechanical sensor component (1) according to claim 17, wherein the seismic mass (4) is deflectable in three mutually perpendicular spatial directions (x, y, z) and wherein the microelectromechanical sensor component (1) has at least two lateral sensing elements (11) which are arranged to detect a deflection of the seismic mass (4) along two mutually perpendicular spatial directions (x, y) parallel to the substrate surface (2a). [19] Microelectromechanical sensor component (1) according to claim 17 or 18, wherein at least one lateral sensing element (11) has an electrode comb structure (11a) formed by mass electrode fingers (11b) arranged on the seismic mass (4) and counter electrode fingers (11c) arranged parallel to the mass electrode fingers (11b) on the substrate (2). [20] Microelectromechanical inertial sensor (20) comprising a microelectromechanical sensor component (1) according to one of the preceding claims and comprising a signal processing unit (21) for applying and processing signals of the microelectromechanical sensor component (1). [21] Microelectromechanical inertial sensor (20) according to claim 20, wherein the microelectromechanical inertial sensor (20) is designed for the detection of structure-borne sound, in particular bone sound, and / or airborne sound.

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