MEMS device with suspension structure and method for manufacturing a MEMS device

Abstract

A MEMS device that has the following features: a body (10) which pivots about a pivot axis (A); a bracket (20); and a suspension structure (30, 30a, 30b) that mechanically couples the body (10) to the support (20), wherein the suspension structure (30, 30a, 30b) comprises a torsion element (50, 150) defining the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) extending at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and second spring elements (52, 54, 152, 154) changes in the direction of the pivot axis (A), and wherein the extension of the first and second spring elements (52, 54, 152, 154) in the direction of the pivot axis (A) is greater than the extension of the torsion element (50, 150) in the direction of the pivot axis (A), wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), is more massive than the torsion element and has a greater extent than the torsion element (50, 150) in the direction perpendicular to the pivot axis (A) and in the direction of the pivot axis (A), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10).

Description

Technical field

[0001] The present disclosure relates to MEMS devices (MEMS = microelectromechanical system) comprising a body mechanically coupled to a support via a suspension structure to pivot about a pivot axis, and to methods for manufacturing corresponding MEMS devices. Background of the invention

[0002] MEMS devices, such as MEMS scanning mirrors, are used in various fields. MEMS devices can have a body, such as a mirror body, that pivots around at least one axis to achieve a desired effect, for example, to reflect electromagnetic energy, visible or invisible light in different directions. MEMS scanning mirrors, for instance, can be used to project two-dimensional images onto a screen. They can also be used in LiDAR applications. LiDAR can be considered an acronym for "Light Imaging, Detection, and Ranging" or a portmanteau of the words light and radar. In general, LiDAR can be considered a surveying technique that measures the distance to a target by illuminating the target with pulsed laser light and measuring the reflected pulses with a sensor.MEMS scanning mirrors can be used for LiDAR in automotive applications. Generally, MEMS scanning mirrors for LiDAR applications can have relatively large dimensions and wide scanning angles to achieve high optical performance. In addition, such MEMS scanning mirrors should exhibit high robustness, meaning they should be insensitive to vibration and thermal stresses and exhibit low mechanical stress. Finding a design and manufacturing process that meets these requirements is challenging.

[0003] To make a MEMS scanning mirror robust against vibrations, the mirror should have low inertia, meaning a lightweight and rigid mirror body. Furthermore, the mirror should exhibit high stiffness in its mounting for all degrees of freedom (DOF) of the mirror body, except for the desired vibration mode(s). To achieve a lightweight and rigid mirror body, the mirror body can have a relatively thin mirror and a thicker reinforcing structure. The mirror body can be mechanically coupled to a mount, such as a mirror frame, to allow rotation around a pivot axis. This pivot axis can extend to a first and a second, opposite end section of the mirror body.The mirror can have a reflective plane on a first main surface and can have a second main surface opposite the first main surface, which is provided with the reinforcement structure.

[0004] One type of such MEMS device operates in resonance with one degree of freedom (DOF) of rotation about the pivot axis. For example, the x-axis can be considered the pivot axis, i.e., Rx represents the rotation about the x-axis. Such MEMS devices can be driven by an electrostatic comb drive. In addition to the desired DOF, e.g., Rx, the pivoting body of a MEMS device, such as a MEMS probe, can exhibit other mechanical degrees of freedom and associated unwanted eigenmodes: Tx, Ty, Tz, Ry, Rz, i.e., translations in the x, y, and z directions and rotations about the y and z axes. For a robust design, it is generally desirable to suppress these unwanted modes, which is equivalent to shifting them to high (eigen) frequencies through appropriate design.

[0005] From DE 10 2007 001 516 B3, a micromechanical component is known which comprises a vibration system with a vibrating body and an elastic suspension by means of which the vibrating body is suspended to allow vibration. The elastic suspension has at least two spring beams. A device for adjusting the resonant frequency of the vibration system is designed to change the position of the at least two spring beams relative to each other, wherein the spring beams can be arranged obliquely to an axis of vibration.

[0006] From US 2015 / 0 203 346 A1, a MEMS scanner is known in which a plurality of torsion beams are arranged between a moving part and a support, wherein an edge of the moving part to which the torsion beams are attached is curved.

[0007] US patent 2007 / 0 171 496 A1 discloses a micromirror mounted on torsion springs at opposite ends, with a comb drive provided on a pair of frames of the micromirror formed symmetrically to the torsion springs.

[0008] US Patent 2008 / 0 054 758 A1 discloses a vibration arrangement in which a vibrating body is mounted on a frame via a torsion beam arranged on a vibration axis and two torsion banks inclined to it. The vibrating body has comb electrodes.

[0009] From US 2005 / 0 219 674 A1, an optical scanning device is known which has a vibrating body which is mounted on a fixed frame via a first spring section and several second spring sections, wherein the second spring sections are excited to cause bending and torsional vibrations of the same.

[0010] From US patent 2014 / 0 327 946 A1, a pivotable mirror is known which has pairs of stiffening beams, wherein the beams of one pair extend from a respective end section of the mirror in opposite directions away from the axis of rotation. Each beam of one pair extends towards each beam of the other pair. Brief description of the invention

[0011] The invention provides a MEMS device according to any one of claims 1 to 3 and a method for manufacturing a MEMS device according to any one of claims 18 to 20. Further developments of the invention are defined in the dependent claims. Examples not covered by the scope of the independent claims are not part of the invention and serve only for illustrative purposes.

[0012] Examples from this disclosure enable MEMS devices that allow mode separation between a desired vibration mode and undesired vibration modes and that can be fabricated easily. According to examples from this disclosure, mode separation similar to that achieved in a leaf spring design can be attained by using a specific suspension structure. Examples from this disclosure enable the torsion bar and the spring elements of the suspension structure to be formed in the same material layer or in the same material layers of a stack of material layers.

[0013] Examples in the present disclosure provide methods for manufacturing such MEMS devices. Brief description of the drawings

[0014] Examples of the revelation are described using the accompanying drawings, wherein: Fig. Figure 1 shows a schematic top view of an example of a MEMS device that has a suspension structure; Fig. Figure 2 shows a schematic top view of an example of a MEMS device, which has two suspension structures at two opposite ends of a body; Fig. Figure 3 shows an example of a suspension structure in which a pivoting body has a projection to which a torsion beam is mechanically coupled; Fig. Figure 4 shows an example of a suspension structure in which a support has a projection to which a torsion beam is mechanically coupled; Fig. Figures 5A to 5C show schematic bottom views of a suspension structure having a torsion bar, a suspension structure having V-springs, and a suspension structure having a combination of a torsion bar and V-springs; Fig. 6A and Fig. 6B show a bottom side view and a cross-sectional view of a MEMS mirror device according to an example of the present disclosure; Fig. 7A and Fig. 7B a bottom view and a perspective view of a suspension structure of the MEMS mirror component Fig. 6A and Fig. Show 6B; Fig. 8A and Fig. 8B a perspective top view and a perspective bottom view of the MEMS mirror component made of Fig. 6A and Fig. Show 6B; Fig. Figures 9 to 14, 15A and 15B show schematic top views of exemplary suspension structures according to the present disclosure; Fig. Figures 16A to 16C show flowcharts of processes for manufacturing a MEMS device according to examples in the present disclosure; and Fig. 17 shows a fashion separation diagram that illustrates a fashion separation of an example of the present disclosure. Detailed description

[0015] Examples of the present disclosure are described in detail below with reference to the accompanying drawings. It should be noted that the same elements or elements with the same functionality are designated with the same or similar reference numerals, and that repeated descriptions of elements designated with the same or similar reference numerals are usually omitted. Thus, descriptions provided for elements with the same or similar reference numerals are interchangeable. A number of details are set forth below to provide a more comprehensive explanation of examples of the disclosure. However, it is obvious to those skilled in the art that examples can be carried out without these specific details.In other cases, known structures and components are shown in the form of block diagrams and not in detail, so as not to obscure examples of the present disclosure. Furthermore, features of the different examples of the present disclosure may be combined unless otherwise stated.

[0016] A MEMS mirror assembly is considered, in which a mirror body is held by two torsion bars at opposite ends. The torsion bars extend in the direction of the pivot axis and thus define the pivot axis. The torsion bars also act as bending beams for the Ty and Tz modes, as well as for the Rz and Ry modes. Ty and Tz can be suppressed by reducing the length L of the torsion bars due to the different scaling of bending and torsional stiffness with length L. The torsional stiffness scales with 1 / L, while the bending stiffness scales with 1 / L.3 The design is scaled. However, since there are upper limits to the mechanical stress in the torsion bars at a given angle of inclination, the torsion bars cannot be arbitrarily shortened. If, in practice, an upper load limit of, for example, 1.1 GPa is set, the torsion bars will have a length where Ty and Tz are very close to Rx, which is unfavorable in terms of robustness.

[0017] To achieve a suspension with high stiffness and suppress modes of different degrees of freedom (DOF), the mirror body can be held in the mirror frame using torsion bars as support beams and additional leaf springs extending perpendicular to the pivot axis. The torsion bars can be formed by narrow torsion bars with a small width in one direction parallel to a substrate plane and perpendicular to the axis of rotation to reduce stiffness with respect to Rx. Such narrow torsion bars, defining the axis of rotation, can suppress the modes Tz and Ry. In the leaf spring principle, a restoring force is provided primarily by the leaf springs. The leaf springs undergo a bending motion when the structure pivots about the pivot axis, i.e., the x-axis. The leaf springs allow the structure to be stiff with respect to Rz and Ty. However, the leaf springs alone would not affect the stiffness curve, i.e.,The restoring torque, compared to the angle of rotation, would be highly nonlinear, leading to unfavorable loading conditions. Furthermore, the maximum achievable angle of rotation would be limited due to the increasing stiffness. For this reason, relief springs are generally used to couple the ends of the leaf springs to the mirror frame, away from the mirror body. The inclusion of relief springs makes the structure less rigid with respect to Ty and Rz, which is detrimental to mode separation requirements. Therefore, determining the precise stiffness of the relief springs represents a design compromise between mode separation requirements and the necessary reduction of nonlinearity.

[0018] In general, the rationale for the leaf spring design can be to shift the unwanted rotational and translational modes to higher frequencies. To prevent excessive stiffness with respect to the desired mode (rotation about the pivot axis), the thickness of the leaf springs in a direction perpendicular to the plane defined by the mirror frame is less than the thickness of the support beams. Thus, a relatively thin layer is required to form the leaf springs, since their stiffness is directly related to the frequency of the springs. 3The thickness scales with respect to the substrate plane, i.e., the mirror plane. In general, the mirror structure, torsion bars, and leaf springs cannot be formed in the same layer due to their differing thickness requirements. Forming the mirror body in the same layer as the leaf spring without an additional stiffening device would make the mirror body too flexible, resulting in very large dynamic deformations. Similarly, the torsion bars cannot be formed in the same layer as the leaf springs because the mode suppression of Tz and Ry relies on their thickness being greater than that of the leaf springs. For capacitive (electrostatic) actuation of the mirror body with comb drives, the drive capacity, and thus the energy that can be introduced into the mechanical oscillator per cycle, and therefore the maximum achievable rotation angle, further scales with the thickness of the comb drive.To achieve adequate drive capacity, a significantly greater thickness of the one or more comb drives is generally required compared to leaf springs. Therefore, the leaf spring design necessitates the creation of separate layers for the leaf springs on the one hand, and for other structures such as the comb drive, the narrow torsion bars, and the stiffening structure of the mirror body on the other. This makes manufacturing more difficult, as more process steps are generally required. Furthermore, attaching the thin leaf springs to the mirror body results in re-entrant corners with stress singularities, which compromise reliability.

[0019] Fig. Figure 1 shows an example of a MEMS device comprising a body 10 that pivots about a pivot axis A, a mount 20, and a suspension structure 30 that mechanically couples the body 10 to the mount 20. The pivot axis is sometimes also called the rotation axis.

[0020] In general, the MEMS device can be formed within a substrate. A substrate plane can be defined as parallel to at least one major surface of the substrate or to two opposing major surfaces of the substrate. The major surfaces of the substrate are those surfaces that have a larger area than the surfaces connecting the major surfaces. Generally, an x-direction and a y-direction in a three-dimensional coordinate system can lie in the substrate plane, and a z-direction can be perpendicular to the substrate plane. The pivot axis can be parallel to the substrate plane. In the case of a MEMS mirror device, the mirror plane of the MEMS mirror device can be parallel to the substrate plane in a non-displaced state of the mirror.

[0021] The MEMS device can have a single suspension structure 30 that mechanically couples a section of the swivel body 10 to the mount 20, as shown in Fig. Figure 1 shows that, in some examples, the MEMS device can have multiple suspension structures that mechanically couple different sections of the swivel body to the mount. Fig. Figure 2 shows an example where two opposite ends of the swivel body 10 are mechanically coupled to the bracket 20 via the suspension structures 30. The bracket 20 can have a frame, as shown in Fig. Figure 2 shows that the suspension structure 30 on both sides of the body 10 can be symmetrical with respect to a plane of symmetry perpendicular to the pivot axis A.

[0022] During operation of the MEMS device, the swivel body 10 is driven to oscillate around the pivot axis A. A drive, e.g., a comb drive, can be provided on the drive body 10. The drive can have first drive structures, e.g., first comb electrodes, on the swivel body 10 and second drive structures, e.g., comb electrodes, on the holder 20. Drive signals can be applied to the drive to cause the swivel body 10 to oscillate around the pivot axis A.

[0023] Fig. 3 and Fig. Figure 4 shows examples of suspension structures and can be considered as representing enlargements of areas V in Fig. 1 and Fig. 2 to represent.

[0024] An example of a suspension structure 30a according to the present disclosure is shown in Fig. Figure 3 shows the suspension structure 30a comprising a torsion element 50, a first spring element 52, and a second spring element 54. A first end of each spring element 52, 54 is mechanically coupled to the body 10, and a second end of each spring element 52, 54 is mechanically coupled to the bracket 20. A first end of the torsion bar 50 is mechanically coupled to a projection 60 of the body 10. The projection 60 extends from the body 10 toward the bracket 20. A second end of the torsion bar 50 is mechanically coupled to the bracket 20. The shape of the projection 60 can be adapted to the configuration of the spring elements 52, 54. The projection 60 can have a shape that changes in the direction of the pivot axis, for example, a shape that narrows in the direction of the pivot axis.In some examples, the projection 60 can have a shape with at least one surface that is essentially parallel to the extent of a spring element of the spring elements 52, 54. For example, the projection 60 can be trapezoidal, as shown. The projection 60 can allow the torsion bar 50 to be shortened. It should be noted that the projection 60 is much more massive than the torsion bar 50, since the projection 60 has a significantly greater extent in the direction perpendicular to the pivot axis than the torsion bar 50. Thus, the projection 60 is essentially torsion-free compared to the torsion bar 50.

[0025] The torsion element(s) define(s) the pivot axis. In examples, the torsion element 50 has an elongated pivot bar. In examples, the torsion element 50 has a plurality of elongated pivot bars that may extend parallel to each other. In examples, the torsion bar(s) may be collinear with the pivot axis A. In examples, the torsion element extends substantially in the direction of the pivot axis. If the torsion element extends substantially in the direction of the pivot axis, the direction of the largest dimension of the torsion element is mainly in the direction of the pivot axis, i.e., the angle between the direction of the largest dimension of the torsion element and the pivot axis is up to 45° but no more. In examples, the angle may be substantially less than 45°, for example, at most 10° or at most 2°.Parallel torsion elements or torsion elements with a small angle make it possible to avoid or reduce non-planar bending for Rx. In some examples, the torsion element may have torsion bars in a V-arrangement such that the angle between the direction of the largest dimension of each torsion bar and the pivot axis is less than 45°. In such examples, the pivot axis may be defined by the bisecting line between the torsion bars. In some examples, the V-shape of such a V-arrangement of a torsion element may extend in a direction opposite to the direction in which a V-shape of the first and second spring elements opens.

[0026] The first and second spring elements 52 and 54 extend at an angle relative to the pivot axis on opposite sides of the torsion element 50, such that the distance between them varies in the direction of the pivot axis A. In the example shown, the distance between sections of the first and second spring elements 52 and 54 closer to the body 10 is greater than the distance between sections of the first and second spring elements 52 and 54 closer to the support 20. In this example, the first and second spring elements 52 and 54 have straight spring bars arranged in a V-shape. In other examples, the spring elements may have spring bars with first and second sections, the first sections extending parallel to each other and the second sections extending such that the distance between them varies in the direction of the pivot axis.In such examples, the spring rods can be arranged in a Y-shape.

[0027] A first extension d1 of the spring elements 52, 54 in the direction of the pivot axis can be greater than a second extension d2 of the spring elements 52, 54 in a direction perpendicular to the pivot axis. In some examples, the spring elements 52, 54, or at least sections thereof, are rod-shaped, and an angle between the longitudinal direction of the rod-shaped spring elements or the rod-shaped sections of the spring elements can be on the order of 5° to 30° or on the order of 5° to 25°. In other examples, the angle can be on the order of 10° to 20°. Thus, in some examples, an angle at least between the rod-shaped sections of the first and the second spring element can be on the order of 10° to 60° or on the order of 10° to 50°, and in other examples, an angle at least between the sections of the first and the second spring element can be on the order of 20° to 40°.

[0028] The extent of the first and second spring elements 52 and 54 in the direction of the pivot axis A is greater than the extent of the torsion element 50 in the direction of the pivot axis. The extent of each element in the direction of the pivot axis is the projection of the respective element onto the pivot axis A, i.e., the length of the element multiplied by the cosine of the angle between the element and the pivot axis.

[0029] Fig. Figure 4 shows another example of a suspension structure 30b, in which the bracket 20 has a projection 62 to which the second end of the torsion bar 50 is mechanically coupled. The projection 62 extends from the bracket 20 to the body 10. The shape of the projection 62 can be adapted to the configuration of the spring elements 52, 54 and can be trapezoidal, as shown in Fig. 4 is shown.

[0030] The first and second ends of the torsion element 50 and the first and second ends of the spring elements 52, 54 can each be attached to the body 10 and the bracket 20. In some examples, the suspension structure can have a relief connection that mechanically couples the second ends of the first and second spring elements, or the second end of the torsion element, or the second ends of the first and second spring elements and the torsion element to the bracket. The relief connection can be configured to allow translation of at least the first and second spring elements or the second end of the torsion element in the direction of the pivot axis at its ends adjacent to the relief connection. In such examples, the extension of the first and second spring elements in the direction of the pivot axis need not be greater than that of the torsion element in the direction of the pivot axis.

[0031] In these examples, at least the torsion element and the first and second spring elements are formed in the same material layer or in the same material layers of a stack of material layers. Accordingly, examples can be manufactured in a simple manner. In such examples, the extents of the first and second spring elements in the direction of the pivot axis need not be greater than those of the torsion element in the direction of the pivot axis.

[0032] In some examples, the MEMS device has a drive element, and the drive structure of the body is formed in the same material layer(s) of a material layer stack as the torsion element and the first and second spring elements. In others, the MEMS device is a MEMS mirror device, and the mirror of the MEMS mirror device is formed in the same material layer(s) of a material layer stack as the torsion element and the first and second spring elements. In some examples, the MEMS mirror device has a stiffening structure that stiffens the mirror and a projection to which the torsion element is mechanically coupled.

[0033] In some examples, the suspension structure(s) is symmetrically designed with respect to the pivot axis to improve the oscillation behavior of the pivoting body. In others, the torsion element is formed by a torsion bar. In still others, the torsion element is formed by a plurality of torsion bars that can extend parallel to each other. In some examples, the first and second spring elements are formed by a spring bar. In some examples, the first spring element can have a plurality of spring bars that can extend parallel to each other. In other examples, the second spring element can have a plurality of spring bars that can extend parallel to each other.

[0034] In some examples, the minimum width of a torsion bar or torsion bars of the torsion element is less than the minimum width of torsion bars of the first and second spring elements.

[0035] As used herein, the term "rod" can generally refer to an elongated element having a length in the longitudinal direction, a width perpendicular to the longitudinal direction, and a thickness perpendicular to both the longitudinal and width directions. In the present description, the longitudinal and width directions can generally be parallel to the substrate plane, and the thickness direction can be perpendicular to the substrate plane.

[0036] In some examples, the body and the suspension structure are designed such that translational and rotational oscillations about axes perpendicular to the pivot axis exhibit resonant frequencies that differ from the harmonic frequencies of the resonant frequency of the rotational oscillation about the pivot axis. The translational DOF Tx becomes relevant in examples where the suspension structure incorporates a stress-relieving connection. In examples without stress-relieving connections, the structure will be stiff with respect to translational oscillations Tx, meaning that oscillations are shifted to very high frequencies.

[0037] The following are examples of the present disclosure with reference to MEMS mirror devices. It should be noted that other examples may refer to other MEMS devices, which may have a body that pivots about a pivot axis. In some examples, the body may pivot to act on a fluid, e.g., to create a fan effect, or to open or close a fluid path.

[0038] The examples described herein achieve similar mode separation to a leaf spring design, but without using leaf springs, so that a single thickness can be used for all springs, the mirror, and the comb drive. An additional reinforcing layer can be used to implement a thick mirror stiffening structure. Mode separation can be achieved by combining V-springs with short, narrow torsion bars. The term V-spring is used here to describe a spring structure that has at least two spring elements arranged such that at least sections of them form the two strokes of the letter V.

[0039] Fig. Figure 5A shows a suspension structure comprising a simply constructed torsion bar 50'. The torsion bar 50' is attached at one end to a coupling section 68 of the mirror body 10. The mirror body 10 has a comb drive structure 70. A second end of the torsion bar 50' forms an anchor 72, which is attached to a support. In this suspension structure with a simply constructed torsion bar, all other modes compete with the Rx mode, especially the Ty and Tz modes, since the torsion bar acts as a bending beam for Ty and Tz. This structure therefore results in poor mode separation.

[0040] Fig. Figure 5B shows a suspension structure with a V-spring configuration. A first and a second spring rod 52' and 54' extend at an angle relative to the pivot axis (x-axis) such that the distance between the spring rods at their first ends differs from the distance between the spring rods at their second ends. The first ends of the spring rods 52', 54' are attached to a coupling section of the mirror body 10, and the second ends of the spring rods 52', 54' are attached to a bracket via an anchor 72. The V-springs have the effect of suppressing the Ty mode and the Rz mode. However, the V-springs cannot suppress the Tz mode and the Ry mode.

[0041] Examples from the present disclosure combine V-springs and a short, narrow torsion bar to suppress all modes Ty, Rz, Tz, and Ry. The result of such a combination is in Fig. Figure 5C shows a short torsion bar 50 and a first and a second V-shaped spring bar 52, 54. A first end of the torsion bar 50 is attached to a coupling projection 60 of the body 10, and a second end of the torsion bar 50 is attached to a support, e.g., via an anchor 72. First ends of the spring bars 52, 54 are attached to the body 10, and second ends of the spring bars 52, 54 are attached to the support, e.g., via the anchor 72. As shown in Fig. As shown in Figure 5C, the second ends of the torsion bar 50 and the spring bars 52, 54 can be coupled by the anchor 72. A stiffening structure 74 of the body 10 is also shown in Figure 5C. Fig. 5C is shown. In examples of the present disclosure, the torsion bar 50 is short and narrow, i.e., shorter than the V-springs in the direction of the pivot axis and narrower than the V-springs. In examples, the thickness of the torsion bar 50 is equal to the thickness of the spring bars 52, 54. Fig. Figure 5C shows a single suspension structure at one end of the body 10. In general, examples provide a pair of corresponding suspension structures, one on each side of the body.

[0042] Using such a combination of a V-spring and a torsion bar, the modes Ty and Rz can be suppressed because the V-spring is subjected to not only a bending component but also a tensile component for these modes. The V-spring is very stiff with respect to the tensile load component.

[0043] The suppression of Tz and Ry by the narrow, short torsion bar(s) occurs because the torsion bars act as bending beams for these modes. Due to their short length L (stiffness ∼ 1 / L), 3 ) and their large z-direction thickness t (e.g. 55 µm, stiffness ∼ t 3They are very stiff with respect to non-planar bending. In contrast, the torsion bars are very soft with respect to the desired Ry mode, since their width is essentially less than their thickness, e.g., at least 10 times less than their thickness. The small planar width (e.g., 4 µm) of the torsion bars reduces their torsional spring constant. This is because, for a torsion bar with a high aspect ratio of the rectangular cross-section, the long side t (thickness) of the rectangular cross-section counts essentially linearly for stiffness, i.e., ∼ t, whereas the short side w (width) counts essentially cubically, i.e., ∼ w 3 Furthermore, the length counts as 1 / L for the torsional stiffness. For this reason, shortening a torsion bar adds much more stiffness to the modes Tz and Ry than it adds to the torsional stiffness Rx.

[0044] Thus, in examples from the present disclosure, reducing the length of the torsion bar compared to the length of the V-springs helps to increase mode separation.

[0045] In examples from the present disclosure, adjusting the shape of the projection 60 can be used to adjust the mass of the pivoting body. This can be used to shift the resonant frequencies of unwanted interfering oscillation modes so that they do not overlap with harmonics of the resonant frequency of the desired mode.

[0046] An example of a MEMS mirror device according to the present disclosure is described below with reference to Fig. 6 to 8 described, whereby Fig. 6A and Fig. Figure 6B shows a schematic bottom view and a schematic side view of a MEMS mirror component. Fig. 7A and Fig. Figure 7B shows a schematic underside view and a perspective view of a suspension structure of the MEMS mirror component and Fig. 8A and Fig. Figure 8B shows a perspective top view and bottom view of the MEMS mirror component.

[0047] The MEMS mirror assembly comprises a pivoting mirror body 10, two suspension structures 30, and a mount 20. In some of the figures, the mount 20 is shown as an anchor; however, it should be noted that the anchor can be part of a mounting structure, for example, a mounting frame formed in a substrate. The mirror 10 is coupled to the mount 20 via the suspension structures 30 on opposite sides of the mirror along the pivot axis A.

[0048] The mirror body 10 has a mirror 100 and a mirror support 102, the mirror support 102 being best positioned in Fig. 8B is shown. The MEMS mirror component can also include a frame (in Fig. (Figures 6 to 8 not shown) have, wherein the mirror body and the frame can be formed in a substrate and wherein the mirror body can be arranged in the frame. The substrate (or the frame) can define a plane, i.e. the (x, y) plane in Fig. 6A. The plane defined by the substrate can be parallel to planes defined by the main surfaces of the substrate. The substrate can have multiple layers in which the mirror body, suspension structures, and frame are formed.

[0049] The mirror body 10 is rotatable about the pivot axis A. The pivot axis A extends parallel to the substrate plane. How best to in Fig. 8A and Fig. As shown in Figure 8B, the mirror support 102 can include an elongated support rod 104 extending along the pivot axis A. The support rod 104 can project from the mirror 100 on both sides of it in the direction of the pivot axis A. Sections of the support rod 104 projecting from the mirror 100 extend beneath projections 60 of the mirror body. Furthermore, the mirror support 102 can include reinforcing beams 106. A first pair of reinforcing beams 106 can extend from a first end section of the mirror 100 in opposite directions away from the pivot axis A. A second pair of reinforcing beams 106 can extend from a opposite second end section of the mirror 100 in opposite directions away from the pivot axis A. The reinforcing beams 106 of the first pair can extend to corresponding ones of the second pair.

[0050] The mirror 100 can be formed on the mirror support 102. Alternatively, the mirror 100 can be attached to the mirror support 102. The surface of the mirror 100 opposite the mirror support 102 defines a mirror plane of the mirror 100. It is apparent to those skilled in the art that the shape of the mirror 100 and the mirror support 102 are independent and can take any shape desired for a particular application, e.g., a circle, an ellipse, a quadrilateral, a rectangle, or any other shape.

[0051] The MEMS mirror device can also include at least one actuating element to provide torque to the mirror body 10 about the pivot axis A. In one example, the actuating element can include mirror comb drive structures 70 attached to the mirror body 10. The mirror comb drive structures 70 can be nested with mounting comb drive structures attached to the mounting, e.g., a frame that holds the pivoting mirror body. Applying a potential difference between the nested mirror comb drive structures and mounting comb drive structures can generate a driving force between the mirror comb drive structures and the mounting comb drive structures, which can produce a torque about the pivot axis A on the mirror body 10. An oscillating electrical potential can be applied to drive the mirror device at its natural frequency.In other examples, actuation methods may include electromagnetic actuation and piezoelectric actuation.

[0052] How best to Fig. 7A and Fig. As shown in Figure 7B, each of the suspension structures 30 has a torsion element 150 and a first and a second spring element 52, 54. In the present example, the torsion element has two torsion bars 150a and 150b that extend parallel to each other. The first ends of the torsion bars 150a, 150b are mechanically coupled to the projection 60. The second ends of the torsion bars 150a, 150b are mechanically coupled to the bracket 20. The torsion bars 150a, 150b extend parallel to the pivot axis A. As explained in detail above, the spring elements 52, 54 extend at an angle relative to the pivot axis A to form a V-spring.

[0053] As in Fig. As shown in Figure 6B, the structures of the mirror body 10 can be formed in a substrate having a stack of layers. A first substack 160 and a second substack 162 are shown in Fig. Figure 6B shows that all structures except the mirror substrate 102 are formed in the first substack, and the mirror substrate 102 is formed in the second substack. Each substack 160 and 162 can be formed by one or more layers of material. In some examples, the first substack 160 can have two silicon layers and a dielectric layer, for example, an oxide, between the silicon layers. All structures of the mirror body except the mirror substrate (stiffening structure) are formed in the same layers of substack 160. In some examples, the second substack 162 can comprise a single silicon layer in which the mirror substrate 102 is formed.

[0054] In some examples, the structures of the support 20 can be formed in the same substrate as the mirror body. In others, the support 20 can have a support frame. The support frame can define a mirror recess in which the mirror body 10 is arranged. The mirror recess can be defined by a recess periphery of the support frame.

[0055] In the example shown, the torsion element 150 has two torsion bars. Using two torsion bars instead of one torsion bar of the same width allows the stiffness of the torsion element to be doubled, particularly for the undesired modes Tz and Ry, but not exclusively for these, while the load with respect to rotation about the pivot axis (mode Rx) in the individual torsion bars does not increase significantly and, in particular, does not double. Thus, increased stiffness with respect to the undesired translational mode Tz and the undesired rotational mode Ry can be obtained without significantly stiffening the structure with respect to rotation about the pivot axis (desired mode Rx), since its Rx stiffness is dominated by the V-springs. In other examples, the torsion elements can have a different number of torsion bars, for example, three or four.Short, narrow torsion bars arranged in parallel are much stiffer with respect to bending in the z-direction compared to torsion. Therefore, adding short, narrow torsion bars can suppress the Tz and Ry modes, while barely affecting the Rx mode, as explained above.

[0056] Fig. Figure 17 shows a mode separation diagram illustrating a mode separation resulting from the above in relation to Fig. The example described in sections 6 to 8 of the present revelation will be obtained. Fig. Figure 17 shows a mode separation across the frequency range in kHz, with the first and second lines from the bottom showing mode separation of known approaches using leaf springs, the third line from the bottom showing mode separation in the case of torsion bars without V-springs, the fourth line from the bottom showing mode separation in the case of V-springs without torsion bars, and the topmost line showing mode separation in the case of V-springs and short, narrow torsion bars. It is evident that examples of the present disclosure provide considerably better separation between the Rx mode and the Rz mode than known leaf spring designs. The separation can be further optimized by adjusting the mass distribution of the pivoting body.

[0057] Compared to load values ​​in known approaches using leaf springs, simulations have shown that such improved mode separation can be achieved without increasing the load in the torsion bars and V-springs at a maximum deflection angle. Specifically, according to the approaches described herein, no load singularities occur due to re-entrant corners at the ends of the leaf spring (leaf spring base and leaf spring head). Here, a re-entrant corner is defined as a sharp corner with an angle exceeding 180° in the material forming the MEMS device. This allows for increased reliability.

[0058] Examples from this disclosure enable simplified processing and handling, as no additional processing of thin films is required to generate leaf springs. Furthermore, unlike leaf spring approaches, there are no stress singularities due to 90° re-entrant corners. Compared to mode separation obtainable with leaf spring approaches, these examples also enable improved mode separation.

[0059] Alternative examples of suspension structures are given below with reference to Fig. Sections 9 to 15 are described. Differences between the respective suspension structures are highlighted below, and repetitions of similar or identical features are omitted.

[0060] At the in Fig. In the example shown in Figure 7A, the second ends of the parallel torsion bars 150a and 150b and the leaf springs 52, 54 forming a V-spring are attached to the support 20, e.g., to the support frame. In the example shown in Figure 7A, the second ends of the parallel torsion bars 150a and 150b and the leaf springs 52, 54 forming a V-spring are attached to the support 20, e.g., to the support frame. Fig. In the example shown in Figure 9, the parallel torsion bars 150a, 150b and the leaf springs 52, 54 forming a V-spring are attached to an anchor 172, and the anchor 172 is mechanically coupled to a support 20, e.g., a support frame, via a relief connection 174. The relief connection 174 can have a number of relief spring bars extending substantially perpendicular to the pivot axis A. First ends of the relief spring bars are attached to the anchor 172, and second ends of the relief spring bars are attached to the support 20. The relief connection 174 is designed to allow translation of the ends of the torsion bars 150a, 150b and the spring bars 52, 54 that are located close to the support in the x-direction. Thus, the relief connection 174 serves to compensate for stresses such as thermal stresses in the x-direction.More precisely, the stress-relieving connection can be designed to compensate for thermal stress effects, such as the expansion of the mirror body due to temperature differences, which could otherwise lead to bulging. It can also compensate for external loads from forces acting on the frame and prevent bulging in such a situation.

[0061] Fig. Figure 10 shows an example of a suspension structure comprising a torsion element 150 with three torsion bars 150a, 150b, 150c arranged parallel to each other. As shown, the torsion bars 150a, 150b, 150c and the spring bars 52, 54 are attached to an anchor 172. The anchor 172 can be attached to a bracket or can be part of a bracket. Alternatively, the anchor 172 can be coupled to a bracket via a relief connection, as shown in Fig. 9 is shown.

[0062] Fig. Figure 11 shows an example of a suspension structure comprising the torsion element 150 with two torsion bars and the spring elements 152 and 154, each comprising first and second spring bars 152a, 152b and 154a, 154b, respectively. Thus, the spring bars can be considered to be arranged in a double V configuration, with spring bars 152a, 154b forming a first V and spring bars 154a, 152b forming a second V. Suppression of the undesired Ty and Rz modes can be improved by using spring elements comprising a plurality of spring bars, which can be arranged parallel to each other. Furthermore, a double-V spring design can approximately double the restoring torque for the Rx mode without a significant increase in the mechanical stress on a single spring bar.

[0063] Fig. Figures 12 to 15 show different examples of how a mechanical coupling of the suspension structures to the body and the support can be achieved.

[0064] According to Fig. In Figure 12, the bracket 20 has a projection 62 to which the second ends of the torsion bars 150a and 150b are mechanically coupled. The first ends of the torsion bars 150a and 150b are coupled to the body 10. Thus, in this example, the torsion element 150 is located closer to the body 10 than to the bracket 20. The projection 62 of the bracket 20 can be formed in the same substrate layers in which the pivoting body 10 is formed. Similar to the projection 60 described above, the shape of the projection 62 can change in the direction of the pivot axis. As in Fig. As shown in Figure 12, the width of the projection 62 can continuously increase towards the mirror.

[0065] According to Fig. In section 13, the spring bars 52 and 54 are arranged such that the distance between sections of the same closer to the body 10 is less than the distance between sections of the same closer to the support 20. Here, the V-shape of the springs opens towards the support 20. While such an arrangement can provide improved suppression or separation of the unwanted modes, it can lead to increased stiffness with respect to rotation about the pivot axis A. As shown in Fig. As shown in Figure 13, the width of the projection 62 can decrease continuously towards the mirror in this embodiment.

[0066] According to Fig. 14. The spring bars 52 and 54 are also arranged such that the distance between sections of them closer to the body 10 is less than the distance between sections of them closer to the support 20. In comparison to Fig. However, the projection 60 is now formed on the swivel body 10, so that the torsion element 150 is arranged closer to the bracket 20 than to the swivel body 10.

[0067] In some examples, the projections extending between the spring elements can be arranged on both the pivoting body 10 and the bracket 20. In such examples, the torsion element can be arranged between the pivoting body and the bracket at the same distance to both.

[0068] Fig. 15A shows an example that corresponds to the one in Fig. The example shown in 9 is similar. In the case of the one in Fig. In the example shown in Figure 15A, however, the torsion element 150, i.e., both torsion bars of the same, is attached to the bracket 20, and the spring elements 52 and 54 are coupled to the bracket 20 via respective relief connections 174a and 174b. In this example, the V-springs are decoupled from the bracket by relief connections to prevent bulging due to thermal expansion. Providing relief connections for the V-springs may be sufficient if the torsion element, e.g., short, narrow torsion bars 150a, 150b, 150c, is not expected to cause significant bulging. Avoiding decoupling of the torsion element by using a relief connection can be effective in suppressing the undesired Tx mode.

[0069] Fig. 15B shows an example similar to the one in Fig. 9 and Fig. The example shown in 15A is similar. However, in the example shown in Fig. In the example shown in Figure 15B, the spring elements 52 and 54 are attached to the bracket 20, and the torsion element 150, i.e., both torsion bars of the same element, are coupled to the bracket 20 via a relief connection 174a, 174b. In this example, the torsion element is decoupled from the bracket via the relief connection. This can be desirable in situations where a strong influence of external forces on the mirror dynamics via the V-springs is not expected, but where the torsion element needs to be protected from such forces.

[0070] Various examples of suspension structures have been described. It is evident to experts that the characteristics of the different examples can be combined in a suitable manner. The varying number of torsion bars and spring bars in the examples is merely an example. Fig. 15A and Fig. 15B and other examples are provided, e.g., one or three torsion bars, as in Fig. 5C and Fig. 10 is shown, or two torsion bars per spring element, as in Fig. 11 is shown.

[0071] The relief connections described above can be provided on the suspension structure on one side of the swivel body or can be provided on the suspension structures on both sides of the swivel body.

[0072] Examples of the present disclosure can result in improved mode separation and therefore mechanical robustness, particularly in cases where a device is operated in a system subject to external vibrations, e.g., in an automotive environment. Examples of the present disclosure provide a spring design for a MEMS device, such as a MEMS micromirror device, operated at the resonance of one rotational degree of freedom. The spring design provides a means of suppressing all stiff-body modes of the swiveling body, e.g., the mirror. This is achieved by a combination of V-springs and short, narrow torsion bars, all of which have the same non-planar (z-direction) thickness.In addition, the spring design can be combined in examples with springs that provide relief in the x-direction and can thus compensate for thermal stress and / or external load.

[0073] A simulation of the spring design using finite element analysis has shown that examples, particularly those featuring a torsion element with two narrow, short torsion bars, exhibit better mode separation than a reference leaf spring design. This was achieved without adversely affecting other behaviors such as dynamic deformation, stiffening curve, dynamic response curves, and load distribution.

[0074] In addition, leaf spring designs generally require the formation of a thin membrane layer, e.g., with a thickness of 10 µm, to realize the leaf spring in a manufacturing process. The formation of thin membranes in the membrane layer, spanning areas in a substrate plane typically ranging from several hundred micrometers to millimeters, involves very delicate and error-prone handling. Such membranes can break during processing. More specifically, these membranes can hermetically seal voids in a stack of material layers during the process if the MEMS device is not yet fully structured. Pressure differentials between such sealed voids under the membranes and the external pressure regularly occur in process chambers and lead to severe mechanical stresses in the membranes, which can ultimately cause breakage.Since examples of the present disclosure do not require such membranes, simplified processing and handling are possible, and fabrication can be more reliable. In general, the formation of leaf springs requires at least one additional layer in the processing technology compared to examples of the present disclosure. In addition to the problem of handling sealed cavities, this additional layer can lead to further processing difficulties, such as the need to perform wafer bonding on pre-structured wafer surfaces and the need to perform several steps of deep reactive ion etching (DRIE) sequentially for different layers on the same wafer side.Bonding on pre-structured surfaces can compromise bond quality compared to bonding on unstructured surfaces, and multiple DRIE steps on the same wafer side carry the risk of subsequent DRIE steps damaging the etched sidewalls formed in previous DRIE steps. With such processing requirements, achieving a reliable manufacturing process is generally challenging.

[0075] Furthermore, the formation of a thin membrane layer in a leaf spring design generally requires the implementation of a mechanism to control its thickness. For example, it might be necessary that its thickness not vary by more than 3%. Such a requirement can be met by forming the thin membrane layer in the component layer of a first silicon-on-insulator (SOI) wafer. However, at least one additional (second) SOI wafer is then required to provide the two thicknesses for the layers in which the other features are formed, such as comb drives, torsion bars, the mirror body, and stiffening structures. Thus, the two discrete thicknesses are provided by the component layer and the handling layer of the second SOI wafer. Therefore, two SOI wafers may be required to process a leaf spring design in a controlled manner.Since examples of the present disclosure do not use leaf springs, examples of the present disclosure can be manufactured using only a single SOI wafer. This can significantly reduce raw material costs, as SOI wafers are expensive.

[0076] In addition, the design approach illustrated by examples in this disclosure avoids the occurrence of re-entrant corners at mechanically stressed locations, which can lead to uncontrolled mechanical load conditions. Such locations occur in leaf spring designs where the thin leaf springs are coupled to other elements, e.g., anchor elements, connecting elements, or body-holding elements, which are formed with a considerably greater thickness.

[0077] Examples in the present disclosure already provide methods for manufacturing such MEMS components.

[0078] As in Fig. As shown in Figure 16A, the method, in examples, comprises forming 200 a body pivoting about a pivot axis, a support, and a suspension structure mechanically coupled to the body of the support in a substrate. The formation of the suspension structure comprises forming 202 a torsion element defining the pivot axis, and a first and a second spring element extending at an angle relative to the pivot axis on opposite sides of the torsion element, such that a distance changes at least between sections of the first and second spring elements in the direction of the pivot axis. The extension of the first and second spring elements in the direction of the pivot axis is greater than the extension of the torsion element in the pivot axis.

[0079] As in Fig. As shown in Figure 16B, the method, in examples, comprises forming 210 a body pivoting about a pivot axis, a support, and a suspension structure mechanically coupled to the body of the support in a substrate. The formation of the suspension structure comprises forming 212 a torsion element defining the pivot axis, and a first and a second spring element extending at an angle relative to the pivot axis on opposite sides of the torsion element, such that a distance at least between sections of the first and second spring element changes in the direction of the pivot axis.A relief connection, which couples at least the first and second spring element or the torsion element to the support, is formed 214, wherein the relief connection is designed to allow a translation of at least the first and second spring element or the torsion element in the direction of the pivot axis at its ends adjacent to the relief connection.

[0080] As in Fig.As shown in Figure 16C, the method, in examples, comprises forming 220 a body pivoting about a pivot axis, a mount, and a suspension structure mechanically coupled to the body of the mount in a substrate. The formation of the suspension structure comprises forming 222 a torsion element defining the pivot axis, as well as a first and a second spring element extending at an angle relative to the pivot axis on opposite sides of the torsion element, such that a distance changes at least between sections of the first and second spring element in the direction of the pivot axis. The torsion element, as well as the first and second spring elements, are formed in the same material layer or in the same material layers of a material layer stack. Thus, the fabrication of the MEMS device can be compared to other designs, e.g.,Designs using leaf springs can be simplified.

[0081] In some examples, the MEMS device can be fabricated using at least one SOI wafer. In other examples, the MEMS device can be fabricated using a wafer that differs from a SOI wafer, which may have a semiconductor layer with a doping implant, an epitaxial layer, or an insulated polysilicon layer on one surface, allowing electrically separable regions to be formed in a comb drive. In such examples, raw material costs and reliability can be further improved.

[0082] Although some aspects have been described as features in the context of a device, it is clear that such a description can also be considered a description of corresponding features of a process. Although some aspects have been described as features in the context of a process, it is clear that such a description can also be considered a description of corresponding features relating to the functionality of a device.

[0083] The preceding detailed description shows that various features are grouped into examples to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the claimed examples require more features than are explicitly stated in each claim. As the following claims reflect, the subject matter of the invention may instead consist of fewer than all the features of a single disclosed example. Thus, the following claims are integrated here into the detailed description, with each claim standing alone as a separate example.Although each claim can stand alone as a separate example, it is noted that, while a dependent claim may refer to a specific combination with one or more other claims, other claims may also contain a combination of the dependent claim with the subject matter of any other dependent claim, or a combination of any feature with other dependent or independent claims. Such combinations are suggested here unless it is stated that a specific combination is not intended. Furthermore, features of a claim are also intended to be included in any other claim, even if that claim is not directly dependent on the independent claim.

[0084] The examples described above are merely illustrative of the principles of this disclosure. It should be noted that modifications and variations of the arrangements and details described herein are obvious to a person skilled in the art. Therefore, they are intended to be limited only by the scope of protection of the appended claims and not by the specific details presented here through the description and explanation of the examples.

Claims

[1] A MEMS device that has the following features: a body (10) which pivots about a pivot axis (A); a bracket (20); and a suspension structure (30, 30a, 30b) that mechanically couples the body (10) to the support (20), wherein the suspension structure (30, 30a, 30b) comprises a torsion element (50, 150) defining the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) extending at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and second spring elements (52, 54, 152, 154) changes in the direction of the pivot axis (A), and wherein the extension of the first and second spring elements (52, 54, 152, 154) in the direction of the pivot axis (A) is greater than the extension of the torsion element (50, 150) in the direction of the pivot axis (A), wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), is more massive than the torsion element and has a greater extent than the torsion element (50, 150) in the direction perpendicular to the pivot axis (A) and in the direction of the pivot axis (A), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10). [2] A MEMS device that has the following features: a body (10) which pivots about a pivot axis (A); a bracket (20); and a suspension structure (30, 30a, 30b) that mechanically couples the body (10) to the support (20), wherein the suspension structure (30, 30a, 30b) comprises a torsion element (50, 150) defining the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) extending at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and second spring elements (52, 54, 152, 154) changes in the direction of the pivot axis (A), and wherein the suspension structure (30, 30a, 30b) has a relief connection (174, 174a, 174b) which mechanically couples the first and second spring elements (52, 54, 152, 154) and / or the torsion element (50, 150) to the support (20), wherein the relief connection (174, 174a, 174b) is configured to allow translation of the first and second spring elements (52, 54, 152, 154) and / or the torsion element (50, 150) in the direction of the pivot axis (A) at its ends adjacent to the relief connection (174, 174a, 174b), wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10). [3] A MEMS device that has the following features: a body (10) which pivots about a pivot axis (A); a bracket (20); and a suspension structure (30, 30a, 30b) that mechanically couples the body (10) to the support (20), wherein the suspension structure (30, 30a, 30b) comprises a torsion element (50, 150) defining the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) extending at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and second spring elements (52, 54, 152, 154) changes in the direction of the pivot axis (A), and wherein the torsion element (50, 150) and the first and second spring elements (52, 54, 152, 154) are formed in the same material layer or in the same material layers of a material layer stack, wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), is more massive than the torsion element and has a greater extent than the torsion element (50, 150) in the direction perpendicular to the pivot axis (A) and in the direction of the pivot axis (A), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10). [4] The MEMS device according to claim 1 or 3, wherein the suspension structure (30, 30a, 30b) has a relief connection (174, 174a, 174b) which mechanically couples the first and second spring element (52, 54, 152, 154) and / or the torsion element (50, 150) to the support (20), wherein the relief connection (174, 174a, 174b) is configured to allow translation of the first and second spring element (52, 54, 152, 154) and / or the torsion element (50, 150) in the direction of the pivot axis (A) at its ends adjacent to the relief connection (174, 174a, 174b). [5] The MEMS device according to claim 2 or 4, wherein the relief connection (174, 174a, 174b) mechanically couples the first and second spring elements (52, 54, 152, 154) and the torsion element (50, 150) to the holder (20), wherein the relief connection (174, 174a, 174b) is configured to allow translation of the first and second spring elements (52, 54, 152, 154) and the torsion element (50, 150) in the direction of the pivot axis (A) at its ends adjacent to the relief connection (174, 174a, 174b). [6] The MEMS device according to claim 1 or 2, wherein the torsion element (50, 150) and the first and second spring elements (52, 54, 152, 154) are formed in the same material layer or in the same material layers of a material layer stack. [7] The MEMS device according to any one of claims 1 to 6, wherein the torsion element (50, 150) has a plurality of torsion bars (150a, 150b, 150c) and / or wherein each of the first and second spring elements (52, 54, 152, 154) has a plurality of spring bars (152a, 152b, 154a, 154b). [8] The MEMS device according to claim 7, wherein the plurality of torsion bars (150a, 150b, 150c) extend parallel to each other and / or wherein the plurality of spring bars (152a, 152b, 154a, 154b) extend parallel to each other. [9] The MEMS device according to any one of claims 1 to 6, wherein the torsion element (50, 150) has at least one torsion bar, wherein each of the first and second spring elements (52, 54, 152, 154) has at least one spring bar, and wherein a minimum width of the torsion bar in a direction perpendicular to a longitudinal direction thereof is less than a minimum width of each spring bar in a direction perpendicular to a longitudinal direction thereof. [10] The MEMS device according to any one of claims 1 to 9, wherein the distance between sections of the first and second spring element (52, 54, 152, 154) closer to the body (10) is greater than the distance between sections of the first and second spring element (52, 54, 152, 154) closer to the holder (20). [11] The MEMS device according to any one of claims 1 to 10, wherein the suspension structure (30, 30a, 30b) is formed symmetrically with respect to the pivot axis (A). [12] The MEMS device according to any one of claims 1 to 11, comprising the suspension structure (30, 30a, 30b) at a first end of the body (10) and a further suspension structure (30, 30a, 30b) at a second end of the body (10). [13] The MEMS device according to claim 12, wherein the suspension structure (30, 30a, 30b) and the further suspension structure (30, 30a, 30b) are symmetrical with respect to a plane perpendicular to the pivot axis (A). [14] The MEMS device according to any one of claims 1 to 13, wherein the body (10) and the suspension structure (30, 30a, 30b) are designed such that translational oscillations in directions perpendicular and parallel to the pivot axis (A) and rotational oscillations about axes perpendicular to the pivot axis (A) have resonant frequencies which differ from harmonic frequencies of the resonant frequency of the rotational oscillation about the pivot axis (A). [15] The MEMS device according to any one of claims 1 to 14, wherein the body (10) is a mirror body comprising a mirror (100) and a comb drive structure (70). [16] The MEMS device according to claim 15, wherein the mirror (100) and the comb drive structure (70) are formed in the same material layer or in the same material layers of a material layer stack as the torsion element (50, 150) and the first and second spring elements (52, 54, 152, 154). [17] The MEMS device according to claim 16, wherein the mirror body has a stiffening structure (74) which stiffens the mirror (100) and the projection (60) with which the torsion element (50, 150) is mechanically coupled. [18] A method for manufacturing a MEMS device, the method comprising the following steps: Forming a body (10) pivoting about a pivot axis (A), a support (20) and a suspension structure (30, 30a, 30b) mechanically coupling the body (10) to the support (20) in a substrate, wherein the formation of the suspension structure (30, 30a, 30b) comprises: Forming a torsion element (50, 150) defining the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) extending at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and the second spring element (52, 54, 152, 154) changes in the direction of the pivot axis (A), wherein the extension of the first and the second spring element (52, 54, 152, 154) in the direction of the pivot axis (A) is greater than the extension of the torsion element (50, 150) in the pivot axis (A), wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), is more massive than the torsion element and has a greater extent than the torsion element (50, 150) in the direction perpendicular to the pivot axis (A) and in the direction of the pivot axis (A), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10). [19] A method for manufacturing a MEMS device, wherein the method comprises the following steps: Forming a body (10) pivoting about a pivot axis (A), a support (20) and a suspension structure (30, 30a, 30b) mechanically coupling the body (10) to the support (20) in a substrate, wherein the formation of the suspension structure (30, 30a, 30b) comprises: Forming a torsion element (50, 150) that defines the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) that extend at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and the second spring element (52, 54, 152, 154) changes in the direction of the pivot axis (A), and Forming a relief connection (174, 174a, 174b) that mechanically couples the first and second spring elements (52, 54, 152, 154) and / or the torsion element (50, 150) to the support (20), wherein the relief connection (174, 174a, 174b) is configured to allow translation of the first and second spring elements (52, 54, 152, 154) and / or the torsion element (50, 150) in the direction of the pivot axis (A) at its ends adjacent to the relief connection (174, 174a, 174b), wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10). [20] A method for manufacturing a MEMS device, the method comprising the following steps: Forming a body (10) pivoting about a pivot axis (A), a support (20) and a suspension structure (30, 30a, 30b) mechanically coupling the body (10) to the support (20) in a substrate, wherein the formation of the suspension structure (30, 30a, 30b) comprises: Forming a torsion element (50, 150) that defines the pivot axis (A), and a first and a second spring element (52, 54, 152, 154) that extend at an angle relative to the pivot axis (A) on opposite sides of the torsion element (50, 150), such that a distance at least between sections of the first and the second spring element (52, 54, 152, 154) changes in the direction of the pivot axis (A), and wherein the torsion element (50, 150) and the first and second spring elements (52, 54, 152, 154) are formed in the same material layer or in the same material layers of a material layer stack, wherein a) the body (10) has a projection (60) extending between the first and second spring elements (52, 54, 152, 154) along the pivot axis (A) and mechanically coupled to the torsion element (50, 150), wherein the projection (60) extends from the body (10) towards the support (20), is more massive than the torsion element and has a greater extent than the torsion element (50, 150) in the direction perpendicular to the pivot axis (A) and in the direction of the pivot axis (A), or b) the support (20) has a projection (62) which extends between the first and the second spring element (52, 54, 152, 154) along the pivot axis (A) and is mechanically coupled to the torsion element (50, 150), the projection (62) being directed from the support (20) towards the body (10). [21] The method according to claim 20, wherein the body (10) is a mirror body, the method further comprising forming a mirror and a comb drive of the mirror body in the same material layer or in the same material layers of a material layer stack as the first and second spring element (52, 54, 152, 154) and the torsion element (50, 150). [22] The method according to claim 21, which comprises forming a stiffening structure of the mirror body in a material layer that differs from the material layer or layers in which the first and second spring elements (52, 54, 152, 154) and the torsion element (50, 150) are formed.

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