MEMS device and manufacturing process comprising at least one elastic stopper structure

Abstract

The invention relates to a MEMS device (1) comprising at least one elastic stopper structure (2-5), a MEMS main structure (6), and at least one contact protrusion (7-10), wherein the elastic stopper structure (2-5) is mechanically separated from the MEMS main structure (6) which is movable relative to the stopper structure, wherein the stopper structure (2-5) is electrically connected to the MEMS main structure (6), wherein the elastic stopper structure (2-5) is anchored to the MEMS device (1) at at least one attachment point by means of an attachment layer (13), wherein the contact protrusion (7-10) is attached to the elastic stopper structure (2-5) and / or to the MEMS main structure (6) to establish at least one contact point between the MEMS main structure (6) and the elastic stopper structure (2-5), and wherein the elastic stopper structure (2-5) has a defined spring force.wherein the contact elevation (7-10) at a defined deflection of the MEMS main structure (6) relative to the MEMS device (1) serves as a stop and the elastic stopper structure (2-5) is flexibly bendable in such a way that a contact force caused by the stop is reduced compared to a rigid stop.

Description

State of the art

[0001] The state of the art includes various methods and devices for the mechanical energy absorption and protection of MEMS components. Conventionally, rigid stopper structures are used to limit the movement of the main MEMS structure and protect it from damage.

[0002] US 2018 / 0045515 A1 discloses a micromechanical sensor for an inertial sensor, comprising a movable seismic mass, a defined number of anchor elements with which the seismic mass is attached to a substrate, and a defined number of stop devices attached to the substrate for stopping the seismic mass, wherein the stop device includes a first resilient stop element, a second resilient stop element, and a fixed stop element. The stop elements are configured such that the seismic mass can successively strike the first resilient stop element, the second resilient stop element, and the fixed stop element.

[0003] The object of the present invention is to provide a MEMS device that minimizes mechanical stresses and adhesion problems, thereby increasing the service life of the components and enabling precise and reproducible manufacturing. Disclosure of the invention

[0004] The invention relates to a MEMS (micro-electromechanical system) device comprising at least one elastic stopper structure, a MEMS main structure, and at least one contact protrusion. The elastic stopper structure is mechanically separated from the MEMS main structure, which is movable relative to the stopper structure. The elastic stopper structure is anchored to the MEMS device at at least one attachment point by means of an attachment layer. The contact protrusion is attached to the elastic stopper structure and / or to the MEMS main structure to establish at least one contact point between the MEMS main structure and the elastic stopper structure.The elastic stopper structure exhibits a spring force, whereby the contact increase at a defined deflection of the MEMS main structure relative to the MEMS device acts as a stop. The elastic stopper structure is flexibly deformable, thus reducing the contact force caused by the stop compared to a rigid stop. The spring force is the force that acts when the stopper structure is elastically deformed. The spring force attempts to return the stopper structure to its original shape. The elastic stopper structure can have a defined spring constant.

[0005] The elastic stopper structure is mechanically separated from the main MEMS structure to allow independent movement, but electrically connected to share the same electrical potential. The main MEMS structure is the part of the device that moves relative to the stopper structure. The mounting layer securely anchors the elastic stopper structure to the MEMS device. The contact riser defines the contact point between the main MEMS structure and the elastic stopper structure and acts as a stop at a defined deflection. The defined spring force determines the ratio of the force acting on the stopper structure to the resulting deflection, thus determining the degree of flexibility and resistance to deformation.

[0006] This allows the MEMS device to be flexibly adapted through the various possible shapes of the elastic stopper structure, while simultaneously offering high mechanical stability and load-bearing capacity, particularly in applications requiring precise acceleration measurements. Furthermore, lower contact forces reduce changes in the adhesion (static friction) between the moving MEMS component and the substrate, which would otherwise lead to permanent component failure.

[0007] One advantage is that the elastic stopper structure is deformable under high accelerations, protecting the main MEMS structure and reducing contact forces. This prevents damage to the MEMS components and extends their service life. Furthermore, the contact force caused by the stop is reduced compared to a rigid stop, minimizing the mechanical stress on the device.

[0008] The main structure of a MEMS accelerometer can, for example, be a seismic mass. The seismic mass is a component that reacts sluggishly to accelerations and thus plays a crucial role in measuring them. It enables the conversion of mechanical motion into electrical signals that can then be analyzed.

[0009] The MEMS device can extend primarily along two orthogonal directions, X and Y, on or above the main extension plane of a substrate. The extension of the MEMS device along a third direction, Z, which is orthogonal to X and Y, is limited by the thickness of the layers used to fabricate the structure. The MEMS device can be mounted / anchored to a base parallel to the X and Y planes. The MEMS device can be formed on or above the main extension plane of a substrate by fabricating various layers using micromechanical MEMS fabrication methods, such as deposition and structuring. The stopper structure can limit the deflection of the main MEMS structure in the Z direction.

[0010] One advantage of using a seismic mass as the main MEMS structure is that it offers high sensitivity and precision in measuring accelerations. This allows even the smallest movements and accelerations to be reliably detected and analyzed, significantly improving the accuracy and performance of the accelerometer.

[0011] Advantageously, the elastic stopper structure can consist of one or more layers. The elastic stopper structure can also be electrically connected to the main MEMS structure, either directly or indirectly. The stopper structure can be manufactured using a micromechanical MEMS fabrication process, such as a structuring process like etching or grinding, and / or a coating process like deposition.

[0012] Advantageously, the elastic stopper structure can exhibit a higher resonant frequency than the resonant frequency of the main MEMS structure. The resonant frequency is the frequency at which the amplitude of a forced vibration is maximized. A higher resonant frequency of the stopper structure compared to the resonant frequency of the main MEMS structure can make the stopper structure less susceptible to external vibrations and damage. This increases the stability and reliability of the MEMS device at high frequencies and dynamic loads.

[0013] Advantageously, the MEMS device can be designed in a cuboid and / or prismatic shape, with a separate elastic stopper structure and a contact elevation arranged in each of the four corners. The separate arrangement of the stopper structures in the four corners of a surface ensures a uniform distribution of the load.

[0014] The MEMS device can also have a prismatic MEMS main structure or MEMS mass, with elastic stoppers being attached at each vertex of the prismatic MEMS main structure, defining the contact points between the MEMS main structure and the substrate of the MEMS device. This improves the mechanical stability and the device's ability to absorb loads from different directions.

[0015] Advantageously, the elastic stopper structure, or each of the elastic stopper structures, can have multiple attachment points to the MEMS device. An attachment point is a location where the stopper structure is connected to the MEMS device. Multiple attachment points reinforce the anchoring of the stopper structure, thereby increasing its stability and resistance to mechanical stress.

[0016] Advantageously, at least one elastic stopper structure can be designed such that the deflection of the MEMS main structure is limited in one direction orthogonal to a plane of the MEMS device, or at least two elastic stopper structures can be designed such that the deflection of the MEMS main structure is limited in two opposite directions orthogonal to a plane of the MEMS device. The orthogonal arrangement precisely controls the freedom of movement of the MEMS main structure, which increases the accuracy and functionality of the device.

[0017] Advantageously, the elastic stopper structure can be made of a material with higher elasticity, yield strength, and / or fracture toughness than the other materials of the MEMS device. A material with high elasticity, yield strength, and / or fracture toughness can deform significantly under load and return to its original shape after unloading. The stopper structure material can be isotropic and / or have a Young's modulus in the range of 140 to 180 GPa and / or a Poisson's ratio in the range of 0.2 to 0.25, and the choice of material is not limited to silicon.

[0018] The mechanical stiffness of the stopper structure can be influenced by its geometry, such as its thickness and dimensions. The resulting stiffness can thus vary between 1 and 500 N / m, depending on the length and width of an elastic element within the stopper structure, such as a beam. The thickness of the flexible beam can, for example, be between one and two micrometers. This extends the service life of the stopper structure and increases its responsiveness, thereby improving the efficiency and reliability of the MEMS device.

[0019] Advantageously, the contact riser can have a geometric shape, such as a strip, a plate, a circle, or an oval, that allows for the most uniform distribution of contact forces. A geometric shape is the physical form of the contact riser that defines the contact point. This reduces mechanical stress and increases the durability of the MEMS device.

[0020] Advantageously, the MEMS device can include a contact protrusion positioned between the stopper structure and the main MEMS structure. This contact protrusion can extend laterally beyond a lateral edge of the stopper structure. This creates an expanded contact area, increasing mechanical stability and ensuring reliable contact.

[0021] The lateral extension of the contact protrusion beyond the edge of the stopper structure enables a more effective distribution of mechanical loads. This minimizes potential failure points and extends the service life of the MEMS device.

[0022] Advantageously, the MEMS device can include a contact riser that has a higher stiffness than the stopper structure and / or is made of a mechanically stiffer material than the stopper structure. This further increases the mechanical strength and durability of the device. The contact riser, which possesses higher stiffness, ensures improved transmission of mechanical forces between the stopper structure and the main MEMS structure.

[0023] Advantageously, the elastic stopper structure can be manufactured using a micromechanical MEMS manufacturing process.

[0024] This ensures high precision and reproducibility of the stopper structure, which improves the quality and reliability of the MEMS device.

[0025] The MEMS device and its components can be manufactured using a micromechanical MEMS manufacturing process, for example a structuring process such as etching or grinding, and / or a coating process such as a deposition process.

[0026] Etching is a well-known structuring method in semiconductor technology and can be one of the following: photolithography, plasma etching, chemical etching, or physical etching. The deposition method can preferably include physical vapor deposition and / or chemical vapor deposition.

[0027] The MEMS device and its components can be fabricated from a first substrate or wafer using a structuring process such as etching or grinding. The remaining elements can then be fabricated from a second substrate or wafer using the same structuring process. Finally, the stopper structures can be attached to the MEMS device, for example, by bonding.

[0028] Advantageously, the MEMS device can incorporate an elastic stopper structure with a variable spring constant determined by the stopper structure's geometry. This enables adaptive mechanical damping that can adjust to varying load conditions. The variable spring constant of the elastic stopper structure means that the structure's stiffness increases with increasing deflection. This allows the MEMS device to remain flexible at small deflections while exhibiting increased stiffness at larger deflections to absorb greater forces and prevent damage.

[0029] Advantageously, the contact enhancement can be coated with a material having a lower coefficient of friction and / or a lower coefficient of adhesion than the contact enhancement itself. This minimizes friction, adhesion, and wear at contact, thereby increasing the service life and efficiency of the MEMS device.

[0030] Advantageously, the elastic stopper structure of the MEMS device can have a serpentine shape with a plate-shaped area for attaching the bonding layer and a serpentine section, with at least one contact protrusion at the leading end of the serpentine section. This creates a flexible yet stable connection that effectively absorbs mechanical loads. The serpentine shape of the stopper structure allows for high flexibility and adaptability to various load situations. The plate-shaped area serves to securely attach the stopper structure to the MEMS device, while the serpentine section provides the necessary elasticity.

[0031] Alternatively, the elastic stopper structure can also have an H-shaped form, with a first and a second mounting layer attached to a first lateral plate-shaped area and a second lateral plate-shaped area of ​​the H-shaped stopper structure for attachment to the MEMS device. This creates a symmetrical and stable structure that enables a uniform distribution of mechanical forces.

[0032] In a central section of a connecting bridge between the first lateral plate-shaped area and the second lateral plate-shaped area of ​​the H-shaped stopper structure, at least one contact protrusion can be provided. This further increases mechanical stability and ensures reliable contact.

[0033] Furthermore, the elastic stopper structure can have a T-shaped form, with the mounting layer for attachment to the MEMS device located on a lateral, plate-shaped area. This enables simple and effective mounting while simultaneously offering high mechanical stability.

[0034] At least one contact protrusion can be attached to the front end of a rib of the T-shaped stopper structure. This achieves improved mechanical coupling and stability, which increases the reliability of the entire MEMS device.

[0035] Advantageously, the MEMS device can be integrated into a MEMS transducer, a MEMS gyroscope, or a MEMS accelerometer. According to one embodiment, the spring-loaded substrate stop can be provided for a z-accelerometer, and the MEMS device can be configured as a z-accelerometer.

[0036] These devices are specific types of MEMS components that perform various functions, such as sound conversion, motion detection, or acceleration measurement. This expands the applicability of the invention to various technological fields, increasing the versatility and utility of the MEMS device.

[0037] Advantageously, the elastic stopper structure can be a multi-layered construction, with each layer being made of a different material to achieve optimized mechanical and electrical properties. This improves the mechanical and electrical properties of the MEMS device, increasing its performance and reliability.

[0038] Advantageously, the contact enhancement can be arranged to enable progressive or stepwise contact with increasing deflection of the MEMS main structure. Progressive contact means that the contact gradually strengthens as the deflection increases. This can be achieved through the specific design of the elastic stopper structure, by progressively increasing the spring force of the elastic stopper structure with increasing deflection. This enables smooth force transmission, which reduces the mechanical stress on the MEMS device and extends its service life.

[0039] Advantageously, the elastic stopper structure can have a shape that enables optimized force transmission with minimal space requirements. Optimized force transmission means that forces are transferred efficiently, while minimal space requirements indicate that the structure is compact. This makes the MEMS device more efficient and space-saving, thus expanding its application possibilities.

[0040] Advantageously, the flexible stopper structure can be operated in an environment protected from external influences such as humidity, dust, and temperature fluctuations. A protected environment prevents external factors from affecting the performance and integrity of the stopper structure. This increases the reliability and lifespan of the MEMS device by minimizing harmful environmental influences.

[0041] Advantageously, the elastic stopper structure can be protected from corrosion and oxidation by a protective coating. A protective coating is a layer applied to the stopper structure to shield it from chemical reactions. This increases the durability and reliability of the MEMS device by preventing corrosion and oxidation.

[0042] Advantageously, the contact riser can be made of a material with high hardness and low wear. A material with high hardness resists deformation, while low wear means it experiences minimal abrasion. This increases the longevity and reliability of the MEMS device by preserving the mechanical integrity of the contact riser.

[0043] Advantageously, the elastic stopper structure can be manufactured using an electrochemical deposition process. Electrochemical deposition is a technique in which materials are deposited using electric current to form the structure. This optimizes the mechanical and electrical properties of the stopper structure, thereby increasing the performance and reliability of the MEMS device.

[0044] The MEMS device can include at least one spring-like stopper structure, which can be located in each of the four corners of the cuboid MEMS device. These stopper structures are mechanically separated from the main MEMS structure, which is movable relative to the stopper structure, but electrically connected to it. The connection is made by a mounting layer that securely anchors the spring-like stopper structure to the MEMS device and simultaneously ensures an electrical connection so that all stopper structures of the MEMS device share the same electrical potential. This electrical connection can be realized by a continuous conduction layer, such as a wiring layer, which acts as a conductor and electrically connects all stopper structures of the MEMS device.

[0045] Advantageously, the spring-like stopper structure is made of a material with high elasticity and low damping to ensure a long service life and high responsiveness.

[0046] A further aspect of the invention is a manufacturing method for a MEMS device comprising at least one elastic stopper structure, a MEMS main structure, and at least one contact riser. The method comprises the steps of: providing a substrate for anchoring the elastic stopper structure, applying at least one binder layer to the substrate, and manufacturing the elastic stopper structure by a micromechanical process, wherein the elastic stopper structure is anchored to the substrate at at least one attachment point by the binder layer and is manufactured with a defined spring force. The contact riser serves as a stop when the MEMS main structure is deflected relative to the MEMS device at a defined deflection, wherein the elastic stopper structure is flexibly bendable such that the contact force caused by the stop is reduced compared to a rigid stop.The electrical connection between the elastic stopper structure and the MEMS main structure shares the same potential. At least one contact elevation is applied to the elastic stopper structure and / or the MEMS main structure to establish at least one contact point between the MEMS main structure and the elastic stopper structure. The MEMS main structure is fabricated using a micromechanical manufacturing process, whereby the elastic stopper structure remains mechanically separated from the MEMS main structure, which is movable relative to the stopper structure.

[0047] A substrate is the base or support layer on which the MEMS components are built. The substrate serves as the foundation for anchoring the stopper structure. A bonding layer is a layer of material applied to the substrate to enable the anchoring of the elastic stopper structure. This bonding layer is electrically conductive and electrically connects the stopper structure to the substrate of the MEMS device. This layer ensures a stable and secure connection between the stopper structure and the substrate. The elastic stopper structure is a flexible structure that is mechanically separated from the main MEMS structure but electrically connected to it. The micromechanical manufacturing process encompasses techniques for the precise fabrication of microscopically small structures to achieve the desired shape and function of the stopper structure.A fixing point is the location where the stopper structure connects to the mounting layer and the substrate to ensure stable fixation. Spring force is the mechanical force exerted by the stopper structure when deformed. A defined spring force means that this force is precisely defined and controlled to ensure the desired mechanical properties of the stopper structure. A contact riser is a rigid component that limits the movement of the main MEMS structure at a specific deflection. This contact riser acts as a stop to prevent overloading of the MEMS components. Flexible bending means that the stopper structure yields and deforms upon contact with the contact riser to absorb and distribute the forces. This reduces the contact force compared to a rigid stop.A contact point is the location where the MEMS main structure and the elastic stopper structure come into contact, defined by the contact area. The MEMS main structure is manufactured using a micromechanical manufacturing process. The MEMS main structure is the part of the MEMS device that performs the primary function and moves relative to the stopper structure. The elastic stopper structure remains mechanically separate from the MEMS main structure, which moves relative to the stopper structure. This means that the stopper structure remains independent of the main structure's movement, thus preserving its freedom of movement. In summary, the manufacturing process describes a precise and controlled method for producing a MEMS device that incorporates a flexible stopper structure to reduce mechanical stress and extend the service life of the MEMS components.

[0048] One advantage of this manufacturing process is that the MEMS device according to the invention, with its elastic stopper structure, exhibits improved mechanical properties. This stopper structure reduces the contact force compared to rigid stops, minimizing the mechanical stress on the MEMS components and thus extending their service life. Furthermore, adhesive forces are minimized. The use of a conventional micromechanical manufacturing process enables high precision and reproducibility of the flexible stopper structure, which increases the overall quality and reliability of the MEMS device.

[0049] The manufacturing process can further include the fabrication of at least one elastic stopper structure in a first silicon layer using a micromechanical manufacturing process, while the MEMS main structure is fabricated in a second, separate silicon layer placed above the first silicon layer. This enables the fabrication of the elastic stopper structure and the MEMS main structure in separate silicon layers using a micromechanical manufacturing process. By separating the structures into different layers, each structure can be optimally manufactured to meet its specific requirements and functions without compromise.The separate fabrication and subsequent arrangement of the silicon layers on top of each other ensures increased flexibility in design and enables more precise control of the mechanical and electrical properties of the MEMS device. Brief description of the drawings

[0050] The invention is explained with reference to the following drawings: Fig. 1a-c shows a MEMS device 1 comprising four elastic stopper structures; Fig. Figures 2a-c show another embodiment of an elastic stopper structure with rounded corners; Fig. Figures 3a-c show another embodiment of an elastic T-shaped stopper structure; Fig. Figures 4a-c show another embodiment of an elastic serpentine or spiral stopper structure; Fig. Figure 5 shows an embodiment of the elastic electrical connection. Examples of implementation

[0051] Fig. Figure 1a shows in the upper left schematic representation a MEMS device 1 comprising a first elastic stopper structure 2, a second elastic stopper structure 3, a third elastic stopper structure 4 and a fourth elastic stopper structure 5 in each of the four corners of the cuboid MEMS device 1. The MEMS device 1 further comprises a MEMS main structure 6 as well as a first contact rise 7, a second contact rise 8, a third contact rise 9 and a fourth contact rise 10 in each of the four corners to the respective elastic stopper structure 3-5.

[0052] The MEMS device shown in the figures is designed as a z-acceleration sensor, and the MEMS device according to the invention can also be used with other MEMS devices.

[0053] In the schematic representation Fig. Figure 1b shows a top view of the MEMS device 1 without the MEMS main structure 6, with components 11 of the MEMS device 1 arranged on a surface 12, the four stopper structures 3-5 being located in the four corners of the MEMS device 1. The MEMS main structure 6 arranged above it has been removed to allow a view into the interior of the MEMS device 1.

[0054] In the schematic representation Fig. Figure 1c shows a section of the schematic representation b), where only the upper right corner is visible and it is clearly recognizable that the first stopper structure 2 is H-shaped and anchored to the MEMS device 1 by means of a fastening layer 13. A connecting web 14 between the two columns 15, 16 is elastically designed and has a defined spring force, so that when in contact with a rigid contact rise 17 on the connecting web 14 with the MEMS main structure 6, the contact forces are reduced compared to a rigid stop.

[0055] The main MEMS structure 6 can, for example, be a seismic mass of a MEMS accelerometer. The seismic mass is a component that reacts sluggishly to accelerations and thus plays an essential role in measuring accelerations. It enables the conversion of mechanical movements into electrical signals that can then be evaluated.

[0056] The MEMS main structure 6 can be mechanically guided relative to the MEMS device 1, in particular to the surface 12 with the components eleven, by guide means (not shown). This ensures movement of the MEMS main structure 6 orthogonally to the surface 12. At a defined deflection of the MEMS main structure 6, the contact protrusions 7-10 serve as stops, whereby the elastic stopper structures 2-5 are flexibly bent so that the contact force caused by the stop is reduced compared to a rigid stop. This prevents damage to the stopper structures 2-5. In addition, the adhesive forces at the contact point between the main structure 6 or MEMS mass and the stopper structures 2-5 are reduced. The contact protrusion 17 on the connecting web 14 projects laterally beyond the connecting web 14, so that the contact forces generated at the stop are better distributed.Each of the individual stopper structures 2-5 is electrically connected to the MEMS main structure 6 by means of the electrical flexible connection 18, as shown in . Fig. 5 shown, so that both the stopper structures 2-5 and the MEMS main structure 6 have the same potential.

[0057] The MEMS device 1 can be integrated into a MEMS sound transducer, a MEMS gyroscope, or a MEMS accelerometer. These devices are specific types of MEMS components that perform various functions, such as sound conversion, motion detection, or acceleration measurement.

[0058] Fig. Figure 2a shows a schematic representation of another embodiment of an elastic stopper structure 20 similar to that in Fig. 1c, however, the H-shaped stopper structure has 20 rounded corners. In Fig. Figure 2b shows a top view of the elastic stopper structure 20. Fig. Figure 2c shows a side view of the elastic stopper structure 20 with the stiff contact elevation 21, which is not as shown in Figure 2c. Fig. 1c is located not on the stopper structure 20, but on the MEMS main structure 6. The contact protrusions 21 can also be located on both the stopper structure 20 and the MEMS main structure 6. At a defined deflection, the contact protrusion 21 on the MEMS main structure 6 comes into contact with the elastic stopper structure 20 as a stop. The stopper structure 20 is electrically connected to the MEMS main structure 6 by means of the electrically flexible connection 18, so that both the stopper structure 20 and the MEMS main structure 6 have the same potential, as in Fig. 5 is shown.

[0059] Fig. 3a another embodiment of an elastic T-shaped stopper structure 30. In Fig. Figure 3b shows a top view of the T-shaped stopper structure 30. Fig. Figure 3c shows a side view of the T-shaped stopper structure 30, wherein the contact protrusion 31 is arranged on the MEMS main structure 6 and, at a defined deflection, comes into contact with a front end of a web 32 of the T-shaped stopper structure 30. The stopper structure 30 also has a plate-shaped area 33 which is connected to the surface 12 of the MEMS device 1 by means of a bonding layer 13. The stopper structure 30 is electrically connected to the MEMS main structure 6 by means of the electrically flexible connection 18, such that both the stopper structure 30 and the MEMS main structure 6 have the same potential, as shown in Figure 3c. Fig. 5 is shown.

[0060] Fig. 4a shows a further embodiment of an elastic serpentine or spiral stopper structure 40 with a corresponding fastening layer 13 as anchoring to the MEMS device 1. Fig. Figure 4b shows a top view. Fig. Figure 4c shows a side view, in which the serpentine stopper structure 40 is anchored to the MEMS device 1 by means of the mounting layer 13, the contact protrusion 41 being arranged on the MEMS main structure 6 and, at a defined deflection, coming into contact with a front end of a section 42 of the helical stopper structure 40. Due to the design of the helical stopper structure 40, the spring force can also be varied depending on the deflection, so that, upon contact, the contact forces are further reduced compared to a rigid stop in order to prevent damage to the MEMS device 1.

[0061] The spiral stopper structure 40 has a plate-shaped area 43, which is rigidly connected to the surface 12 of the MEMS device 1 by means of a bonding layer 13, and a serpentine area 44, which has a defined spring force. The stopper structure 40 is electrically connected to the MEMS main structure 6 by means of the electrically flexible connection 18, such that both the stopper structure 40 and the MEMS main structure 6 have the same potential, as in Fig. 5 is shown.

[0062] Fig.Figure 5 shows a schematic representation of the electrical flexible connection 18 comprising a connecting element 50 for the mechanical connection of the electrical flexible connection 18 to the moving MEMS main structure 6 (not shown), flexible webs 51 between the connecting element 50 and a frame 52, wherein the frame 52 electrically connects the individual stopper structures 2-5 to each other by means of the conductive mounting layers 13. The flexibility of the flexible webs 51 ensures the desired elasticity and vibration behavior of the MEMS main structure relative to the stopper structures 2-5. 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 2018 / 0045515 A1

[0002]

Claims

[1] MEMS device (1) comprising at least one elastic stopper structure (2-5), a MEMS main structure (6) and at least one contact rise (7-10), wherein the elastic stopper structure (2-5) is mechanically separated from the MEMS main structure (6) which is movable relative to the stopper structure, wherein the elastic stopper structure (2-5) is anchored to the MEMS device (1) at at least one attachment point by a fastening layer (13), wherein the contact rise (7-10) is attached to the elastic stopper structure (2-5) and / or to the MEMS main structure (6) to establish at least one contact point between the MEMS main structure (6) and the elastic stopper structure (2-5), wherein the elastic stopper structure (2-5) has a spring force, wherein the contact rise (7-10) acts as a stop at a defined deflection of the MEMS main structure (6) relative to the MEMS device (1) and the elastic stopper structure (2-5) is flexible so flexible,that the contact force caused by the stop is reduced compared to a rigid stop. [2] MEMS device (1) according to claim 1, wherein the elastic stopper structure (2-5) has one or more layers, wherein the stopper structure (2-5) is electrically connected to the MEMS main structure (6). [3] MEMS device (1) according to claim 1 or 2, wherein the elastic stopper structure (2-5) has a higher resonant frequency than the MEMS main structure (6). [4] MEMS device (1) according to one of the preceding claims, wherein the MEMS device (1) is cuboid and / or prism-shaped, wherein in each of the four corners of the MEMS device (1) a separate elastic stopper structure (2-5) and a contact protrusion (7-10) are arranged, which in each of the corners serves as a stop during the movement of the MEMS main structure (6). [5] MEMS device (1) according to one of the preceding claims, wherein the elastic stopper structure (2-5) or each of the elastic stopper structures (2-5) has multiple attachment points on the MEMS device (1). [6] MEMS device (1) according to one of the preceding claims, wherein the at least one elastic stopper structure (2-5) is designed such that the deflection of the MEMS main structure (6) is limited in one direction orthogonal to a plane of the MEMS device (1), or wherein at least two elastic stopper structures (2-5) are designed such that the deflection of the MEMS main structure (6) is limited in two opposite directions orthogonal to a plane of the MEMS device (1). [7] MEMS device (1) according to one of the preceding claims, wherein the contact enhancement (7-10) has a geometric shape such as a strip, a plate, a circular shape or an oval shape, such that the selected geometric shape enables a distribution of the contact forces as uniformly as possible. [8] MEMS device (1) according to one of the preceding claims, wherein the contact elevation (7-10) is arranged between the stopper structure (2-5) and the MEMS main structure (6), wherein the contact elevation (7-10) extends laterally beyond a lateral edge of the stopper structure (2-5). [9] MEMS device (1) according to one of the preceding claims, wherein the contact enhancement (7-10) has a higher stiffness than the stopper structure (2-5) and / or is made of a mechanically stiffer material than the material of the stopper structure (2-5). [10] MEMS device (1) according to one of the preceding claims, wherein the elastic stopper structure (2-5) has a variable spring constant which is determined by the geometry of the stopper structure (2-5), wherein the spring constant of the stopper structure (2-5) increases with a higher deflection of the stopper structure (2-5). [11] MEMS device (1) according to one of the preceding claims, wherein the contact enhancement (7-10) is provided with a coating of a material having a lower coefficient of friction and / or a low coefficient of adhesion, so that friction, adhesion and wear upon contact are minimized. [12] MEMS device (1) according to one of the preceding claims, wherein the elastic stopper structure (2-5) has a serpentine shape with a plate-shaped area for attaching the mounting layer (13) and a serpentine area, wherein at least one contact elevation (7-10) is attached to a front end of the serpentine area and / or the elastic stopper structure (2-5) has an H-shaped form, wherein a first mounting layer (13) and a second mounting layer for attachment to the MEMS device are attached to a first lateral plate-shaped area and to a second lateral plate-shaped area of ​​the H-shaped stopper structure (2-5),wherein at least one contact elevation (7-10) is provided in a central region of a connecting web between the first lateral plate-shaped region and in the second lateral plate-shaped region of the H-shaped stopper structure (2-5) and / or the elastic stopper structure (2-5) has a T-shaped form, wherein the fastening layer (13) for attachment to the MEMS device (1) is arranged on a lateral plate-shaped region, wherein at least one contact elevation (7-10) is provided on a front end of a web of the T-shaped stopper structure (2-5). [13] MEMS device (1) according to any of the preceding claims, which is integrated into a MEMS sound transducer, a MEMS gyroscope or a MEMS accelerometer. [14] Manufacturing method of a MEMS device (1) comprising at least one elastic stopper structure (2-5), a MEMS main structure (6) and at least one contact enhancement (7-10), the method comprising the following steps: providing a substrate for anchoring the elastic stopper structure (2-5); applying at least one attachment layer (13) to the substrate;Manufacturing the elastic stopper structure (2-5) by a micromechanical manufacturing process, wherein the elastic stopper structure (2-5) is anchored to the substrate at at least one attachment point by the attachment layer (13), and wherein the elastic stopper structure (2-5) is manufactured with a defined spring force, wherein the contact elevation (7-10) acts as a stop at a defined deflection of the MEMS main structure (6) relative to the MEMS device (1), and the elastic stopper structure (2-5) is flexibly bendable such that a contact force caused by the stop is reduced compared to a rigid stop; electrical connection of the elastic stopper structure (2-5) with the MEMS main structure (6) to share the same potential;Attaching at least one rigid contact elevation (7-10) to the elastic stopper structure (2-5) and / or to the MEMS main structure (6) to establish at least one contact point between the MEMS main structure (6) and the elastic stopper structure (2-5); fabricating the MEMS main structure (6) by a micromechanical manufacturing process, wherein the elastic stopper structure (2-5) remains mechanically separated from the MEMS main structure (6) which is movable relative to the stopper structure. [15] Manufacturing method according to claim 14, wherein the at least one elastic stopper structure (2-5) is manufactured in a first silicon layer by means of the micromechanical manufacturing process, wherein the MEMS main structure (6) is manufactured in a second separate silicon layer by means of the micromechanical manufacturing process, which is arranged above the first silicon layer.

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