Micromechanical sensor and method for manufacturing a micromechanical sensor

Abstract

Micromechanical sensor (1) with a substrate (10) having a principal extension plane (100) and a mass element (30) movable relative to the substrate (10), wherein the movable mass element (30) is coupled to the substrate (10) via a spring structure (20), wherein the spring structure (20) comprises a first and second spring element (21, 22), wherein the first and second spring elements (21, 22) extend substantially parallel to each other over certain distances, characterized in that the spring structure (20) comprises a first and second compensation element (23, 24) for quadrature compensation, wherein the first compensation element (23) is connected to the first spring element (21), wherein the second compensation element (24) is connected to the second spring element (22), wherein the first spring element (21) has a first spring structure width (210) extending along a transverse direction (102). exhibitswherein the second spring element (22) has a second spring structure width (220) extending along the transverse direction (102), wherein the first compensation element (23) extends in a first sub-area parallel to the transverse direction (102) along a first width (230), wherein the first spring structure width (210) and the first width (230) are different, wherein the second compensation element (24) extends in a second sub-area parallel to the transverse direction (102) along a second width (240), wherein the second spring structure width (220) and the second width (240) are different, and wherein a flank (211) of the first spring element (21) extends along a longitudinal direction (201) towards the substrate (10), , -- wherein the first width (230) of the first compensation element (23) and the second width (240) of the second compensation element (24) are substantially equal when the longitudinal direction (201) and a normal direction (101) are oriented parallel to each other, wherein the normal direction (101) is oriented substantially perpendicular to the principal extension plane (100) of the substrate (10), and / or -- wherein the first width (230) of the first compensation element (23) and the second width (240) of the second compensation element (24) are different when the longitudinal direction (201) and the normal direction (101) are oriented non-parallel to each other.

Description

State of the art

[0001] The invention relates to a micromechanical sensor according to the preamble of claim 1.

[0002] Such micromechanical sensors are well known. For example, micromechanical sensors are used to detect accelerations and / or rotational rates, where the micromechanical sensor has a substrate and silicon structures that are movable relative to the substrate.

[0003] For example, the movable silicon structures comprise two movable masses that are moved antiparallel to each other along a drive plane, whereby a deflection movement of the two masses out of the drive plane is capacitively detected to determine the rotation rate of the micromechanical sensor. The drive plane can be oriented essentially parallel or perpendicular to the main extension plane of the substrate.

[0004] The fabrication of such movable silicon structures typically takes place in two successive steps. First, the silicon structures are created by etching a functional layer. Then, the silicon structures are exposed by removing a sacrificial layer between the substrate and the silicon structures.

[0005] A disadvantage of known micromechanical sensors is that the flanks of the silicon structures (also known as etch flanks or trench flanks) generated during the structuring of the functional layer are often inclined at an angle (also known as the etch angle or trench angle) relative to a normal direction that is essentially perpendicular to the main extension plane of the substrate. This induces a deviation (false deflection) of the two moving masses. This false deflection occurs even when the micromechanical sensor is in a rest position, resulting in a wobbling motion of the two seismic masses and generating a false signal (i.e., a so-called quadrature signal). Quadrature compensation can typically only be reduced by comparatively complex additional measures. Disclosures are provided, for example, in DE 10 2013 216 935 A1 and EP 2 195 662 B2. Disclosure of the invention

[0006] It is an object of the present invention to propose a micromechanical sensor and a method for manufacturing a micromechanical sensor such that the micromechanical sensor has a reduced quadrature signal compared to the prior art.

[0007] The micromechanical sensor according to the invention and the method according to the invention for producing a micromechanical sensor according to dependent claims 1 and 6 have the advantage over the prior art that a comparatively compact and cost-effective micromechanical sensor is provided, which nevertheless has a reduced quadrature compared to the prior art. This advantageously makes it possible for the first and second compensation elements (which are also referred to in this document as the first or second additional structure) to be shaped and / or arranged on the first or second spring element such that the spring structure, even when it is formed at an angle by the etching process (i.e., in particular, has a trench flank or etched flank with a non-zero trench angle), behaves mechanically like a straight-etched spring – i.e., does not generate any wobbling motion.The wobble motion refers in particular to a mechanically induced misdeflection or deviation of the deflection motion from a drive direction, which occurs during a deflection movement of the mass element along the drive direction (oriented parallel or perpendicular to the main extension plane of the substrate). This means, in particular, that due to the attachment of the first compensation element to the first spring element and the attachment of the second compensation element to the second spring element, it is advantageously possible to largely prevent the wobble motion typically occurring in the prior art, even with a non-zero trench angle, especially when the micromechanical sensor is in a rest position. This at least reduces, or even completely eliminates, the quadrature error signal (false signal) generated by the wobble-like movement of the mass element compared to the prior art.According to a preferred embodiment of the present invention, the first and second spring elements are coupled to each other over a certain distance. Due to the realization of two spring elements (i.e., the first and second spring elements) that run substantially parallel to each other over a certain distance and are, in particular, mechanically coupled to each other over that distance, it is advantageously possible to reduce the quadrature signal compared to the prior art by compensating (or even deliberately overcompensating) a misalignment of one of the two spring elements with the other spring element. This provides a micromechanical sensor with a comparatively simple-to-manufacture compensation element for mechanical quadrature compensation, thereby also reducing the development effort and the susceptibility to errors of the entire sensor compared to the prior art.Preferably, the two spring elements are designed as spring beams, although alternatively, the spring elements can also have a curved shape – for example, a U-shape. Furthermore, it is advantageous that, due to the mechanical quadrature compensation provided by the compensation element, a comparatively compact evaluation circuit can be used, thus reducing the size of the angular rate sensor compared to the prior art. Preferably, the two compensation elements are formed from a first layer and the two spring elements from a second layer, with the first layer being arranged between the substrate and the second layer. More preferably, the compensation elements are at least partially shaped during the structuring of the second layer such that the first spring structure width and the second width are different, and so that the second spring structure width and the second width are different.In this way it is advantageously possible to provide a micromechanical sensor in such a way that the shape and / or arrangement of the first and second compensation element is adapted to the trench angle realized during the structuring of the second functional layer.

[0008] Advantageous embodiments and further developments of the invention can be found in the dependent claims and in the description with reference to the drawings.

[0009] According to the micromechanical sensor according to the invention, it is provided that one flank of the first spring element extends along a longitudinal direction towards the substrate, -- wherein the first width of the first compensation element and the second width of the second compensation element are substantially equal if the longitudinal direction and a normal direction are oriented parallel to each other, the normal direction being oriented substantially perpendicular to the principal extension plane of the substrate, and / or -- wherein the first width of the first compensation element and the second width of the second compensation element are different if the longitudinal direction and the normal direction are not parallel to each other.

[0010] According to the invention, it is advantageously possible for the first width of the first compensation element and the second width of the second compensation element to be predetermined in a self-adjusting manner by the trench angle (which is enclosed between the normal direction and the longitudinal direction). This allows quadrature compensation to be achieved in a comparatively simple and efficient way.

[0011] According to a further preferred embodiment, the first compensation element is connected to the first spring element in such a way that the first compensation element is at least partially arranged between the substrate and the first spring element, wherein the second compensation element is connected to the second spring element in such a way that the second compensation element is at least partially arranged between the substrate and the second spring element.

[0012] According to the invention, it is advantageously possible to arrange the first and second compensation elements for quadrature compensation on the first and second spring elements, respectively (particularly below the respective spring element), so that the compensation elements are at least partially formed together with the spring elements during the structuring of the second layer. In this way, it is advantageously possible to manufacture the micromechanical sensor in a self-adjusting manner – i.e., the shape and / or arrangement of the first and second compensation elements is adapted depending on the trench angle realized during the structuring of the second functional layer.

[0013] According to a further preferred embodiment, it is provided that a first cross-sectional area of ​​the first spring element and a second cross-sectional area of ​​the second spring element have the same cross-sectional shape, wherein in particular the first spring structure width and the second spring structure width are the same size.

[0014] According to the invention, this makes it advantageously possible for the quadrature compensation to be realized mainly by the first and second compensation elements.

[0015] According to a further preferred embodiment, the first compensation element extends in a further first sub-area parallel to the transverse direction along a further first width, wherein the second compensation element extends in a further second sub-area parallel to the transverse direction along a further second width, wherein the further first width is greater than the first spring structure width and / or wherein the further second width is greater than the second spring structure width.

[0016] According to the invention, it is advantageously possible to arrange a compensation element on the spring element such that the first and / or second sub-section extends parallel to the transverse direction beyond the spring element, so that a comparatively narrow first sub-section in combination with a relatively wide second sub-section (in particular by L-shaped compensation elements) allows the mechanical stiffness of the spring structure to be adjusted (self-adjusting) depending on the width of the second sub-section (defined by the trench angle). Furthermore, it is advantageously possible to attach a compensation element to the spring element while largely avoiding an additional increase in the overall height of the micromechanical sensor along the normal direction, compared to the prior art.

[0017] According to a further preferred embodiment, the first sub-area is mainly arranged in a region of the first spring element facing the second spring element, wherein the second sub-area is mainly arranged in a region of the second spring element facing the first spring element.

[0018] According to the invention, this makes it advantageously possible to realize a geometric shape and / or arrangement of the first and second compensation element adapted to the respective trench angle (self-adjusting), so that mechanical quadrature compensation is realized in a comparatively simple and efficient manner.

[0019] According to a preferred embodiment of the method according to the invention, the spring structure is designed such that the first spring element has a first spring structure width extending along a transverse direction and the second spring element has a second spring structure width extending along the transverse direction, wherein in the fourth method step the first compensation element is designed such that the first compensation element extends in a first partial area parallel to the transverse direction along a first width and the first spring structure width and the first width are different, wherein in the fourth method step the second compensation element is designed such that the second compensation element extends in a second partial area parallel to the transverse direction along a second width and the second spring structure width and the second width are different.

[0020] According to the invention, this makes it advantageously possible for the first and second compensation elements to be formed from the first layer, so that the first width of the first compensation element and the second width of the second compensation element are adapted to the trench angle.

[0021] According to a further preferred embodiment of the method according to the invention, it is provided that the first compensation element is connected to the first spring element in an area facing the second spring element and / or that the second compensation element is connected to the second spring element in an area facing the first spring element.

[0022] According to the invention, this makes it advantageously possible to produce the first and second compensation elements in the same structuring or etching step in which the first and second spring elements are also produced. In this way, it is advantageously possible to manufacture the micromechanical sensor in a self-adjusting manner – i.e., the shape and / or arrangement of the first and second compensation elements is adapted depending on the trench angle achieved during the structuring of the second functional layer.

[0023] According to a further preferred embodiment of the method according to the invention, it is provided that in the fourth method step the first spring element is designed such that a flank of the first spring element extends along a longitudinal direction towards the substrate, wherein a trench angle is included between the longitudinal direction and a normal direction that is substantially perpendicular to a principal extension direction of the substrate, wherein the spring structure is formed such that the first width and / or the further first width of the first compensation element is determined by the trench angle and / or that the second width and / or the further second width of the second compensation element is determined by the trench angle.

[0024] According to the invention, this makes it advantageously possible to arrange the compensation elements relative to the spring such that their widths are adapted to the trench angle in such a way that the quadrature induced by sloping trench flanks is compensated by the compensation elements. In particular, in the fourth process step, i.e., in the trenching process, the compensation elements are formed at least partially together with the spring elements.

[0025] Exemplary embodiments of the present invention are shown in the drawings and explained in more detail in the following description. Brief description of the drawings

[0026] They show Fig. 1, Fig. 2, Fig. 3, Fig. 4 to Fig. 5 a micromechanical sensor according to different embodiments of the present invention, Fig. 6, Fig. 7 to Fig. 8 a spring structure of a micromechanical sensor according to different embodiments of the present invention, Fig. 9 a micromechanical sensor and a spring structure according to an embodiment of the present invention, Fig. 10a - 10f and 11a to 11g a method for manufacturing a micromechanical sensor according to different embodiments of the present invention and Fig. 12 a spring structure of a micromechanical sensor according to different embodiments of the present invention. embodiment(s) of the invention

[0027] In the various figures, identical parts are always marked with the same reference symbols and are therefore usually only named or mentioned once.

[0028] In Fig. Figure 1 shows a schematic cross-sectional view of a micromechanical sensor 1 according to an embodiment of the present invention. For example, the micromechanical sensor 1 is configured as a gyroscope and / or accelerometer.

[0029] The micromechanical sensor 1 comprises a substrate 10 having a principal extension plane 100, where a normal direction 101 oriented essentially perpendicular to the principal extension plane 100 is shown. Furthermore, the micromechanical sensor has a mass element 30 movable relative to the substrate 10, wherein the movable mass element 30 is coupled to the substrate 10 via a spring structure 20 (only indicated here) or is elastically connected to the substrate 10. The mass element 30 and the spring structure 20 are collectively referred to here as movable silicon structures 20, 30.

[0030] Furthermore, the micromechanical sensor 1 preferably comprises a first layer 301 and a second layer 302, wherein the first layer 301 is arranged between the substrate 10 and the second layer 302. For example, the first layer 301 comprises a sacrificial layer, preferably an oxide layer, and / or the second layer 302 comprises a functional layer 302, preferably a silicon layer. Here, at least a portion of the first layer 301 has been removed—i.e., the movable silicon structures 20, 30 are exposed. Furthermore, the first layer 301 particularly comprises a third layer 303—for example, a comparatively thin third layer 303, preferably a polysilicon layer.

[0031] To fabricate the movable silicon structures 20, 30, the second layer 302 is structured (in particular by applying an etching process), creating grooves 31 in the second layer with a comparatively high aspect ratio. Subsequently, the first layer 301 is at least partially removed—that is, in particular, at least the sacrificial layer of the first layer 301 located beneath the comparatively thick second layer 302 is removed (see reference numeral 301'), so that the silicon structures 20, 30 are freely movable. Additionally, the third layer 303, located between the movable silicon structures 20, 30 and the substrate, is shown here. This third layer 303 comprises, for example, a suspension area 40 for suspending the movable silicon structures 20, 30 and / or an electrode area 60 beneath the movable mass element 30 and / or a conductor area.

[0032] In Fig. Figure 2 shows a micromechanical sensor 1 according to an embodiment of the present invention in a schematic cross-sectional view, wherein the embodiment shown here is essentially identical to the other embodiments of the present invention. The micromechanical sensor 1 comprises a cap structure 70 for hermetically sealing the movable structures 20, 30, wherein the movable structures are arranged in a cavity 71. The cap structure 70 is produced, for example, by a bonding process by depositing a cap wafer onto a sensor wafer, thus forming the cavity 71. Furthermore, a conductor track region 80 made from the third layer 303 for electrically contacting the movable structures 20, 30 arranged in the cavity 71 is shown.

[0033] In Fig. 3 and Fig. Figure 4 shows a micromechanical sensor 1 according to an embodiment of the present invention in a schematic cross-sectional view, wherein the embodiment shown here is essentially identical to the other embodiments of the present invention, wherein the micromechanical sensor 1 shown here comprises the mass element 30 and a further mass element 30' (which are hereinafter also referred to as two masses 30, 30'). The two masses 30, 30' are subjected to a drive movement such that the two masses 30, 30' are deflected antiparallel (oppositely parallel) along a drive direction 102 (drive deflection). Fig. Figure 3 (above) shows the two masses 30, 30' in a rest position of the micromechanical sensor 1, i.e., the micromechanical sensor is located here in an inertial frame of reference. Due to the antiparallel drive displacement of the two masses, the micromechanical sensor 1 is configured such that an output signal from the micromechanical sensor 1 provides information about whether the micromechanical sensor is subjected to an acceleration (see Figure 3). Fig. 3, below) is acted upon - whereby the two masses 30, 30' are deflected parallel to each other along a detection direction (here along the normal direction 101) - or with a rotation rate (see Fig. 4, above) is acted upon – whereby the two masses 30, 30' are deflected antiparallel to each other along the detection direction (here along the normal direction 101). Such a deflection of the two masses 30, 30' is also referred to here as the detection deflection – the corresponding movement of the two masses 30, 30' as the detection movement. Here, the drive deflection occurs along the drive direction 102, which is oriented parallel to the main extension plane 100, and the detection deflection occurs along the normal direction 101, which is oriented perpendicular to the main extension plane 100. Alternatively, the micromechanical sensor 1 is configured such that the drive deflection occurs along the normal direction 101, which is oriented perpendicular to the main extension plane 100, and the detection deflection occurs along the drive direction 102, which is oriented parallel to the main extension plane 100.It was found that in both cases, with the current state of the art, it is comparatively difficult to achieve a movement of the two masses exactly parallel or perpendicular to the principal extension plane 100 of the substrate 10, since the structuring of the functional layer is not completely perpendicular and different micromechanical sensors exhibit different trench angles. A resulting effect is exemplified in [reference]. Fig. Figure 4 (below) shows that non-perpendicular trench angles cause the drive movement and / or detection movement of the two masses 30, 30' to each exhibit a movement component perpendicular to the desired direction of movement (i.e., the drive direction or detection direction). The two masses 30, 30' also perform a wobbling motion (with a movement component along the detection direction) even when the micromechanical sensor 1 is in its rest position. This wobbling motion (quadrature) causes, in particular, a false signal (a so-called quadrature signal), which, according to the invention, is prevented or reduced by mechanical quadrature compensation.

[0034] In Fig. Figure 5 shows a micromechanical sensor 1 according to an embodiment of the present invention in a schematic view, wherein in particular the embodiment shown here is essentially identical to the other embodiments of the present invention. Fig. Figure 5 (right side) shows a schematic top view of the micromechanical sensor 1, with the spring structure 20 also depicted. The movable mass element 30 is elastically connected to the suspension area 40 via the spring structure 20, so that the movable mass element 30 performs a drive movement along the drive direction 102 (also referred to here as the transverse direction 102) when the movable mass element 30 is subjected to the drive movement by a drive arrangement 50 of the micromechanical sensor 1. The spring structure 20 comprises a first and second spring element 21, 22, wherein in Fig. Figure 5 (left side) shows only the first spring element 21 of the spring structure 20 along the section line XX' in a schematic cross-sectional view, whereby the following description of the first spring element 21 also applies accordingly to the second spring element 22. The first spring element 21 has a flank 211 (trench flank or etched flank) that extends along a longitudinal direction 201 towards the substrate 10. Here, the longitudinal direction 201 and the normal direction 101 are not parallel – i.e., the longitudinal direction 201 forms a non-zero trench angle 201' with the normal direction 101. This means, for example, that an upper centroid 215 of an upper part of the first spring element 21 is arranged offset along a projection direction parallel to the normal direction 101 relative to a lower centroid 215' of a lower part of the first spring element 21, so that the wobbling motion is generated - i.e.In this example, the inclined flank 211 of the first spring element 21 causes the mass element 30 to be moved along the direction of movement 202 which has a component parallel to the normal direction 101, when the mass element 30 is driven along the drive direction 102 of the substrate 10 which is parallel to the main extension plane 100 - even when the micromechanical sensor 1 is in a rest position.

[0035] In Fig. Figure 6 shows a spring structure 20 of a micromechanical sensor 1 according to different embodiments of the present invention in a schematic cross-sectional view, wherein in particular the embodiment shown here is essentially identical to the other embodiments of the present invention. Fig. Figure 6 shows a first spring element 21, wherein the longitudinal direction 201 and the normal direction 101 are oriented parallel to each other (left side) or wherein the longitudinal direction 201 and the normal direction 101 are oriented non-parallel to each other (middle representation and right side).

[0036] In Fig. Figure 7 shows a schematic cross-sectional view of a spring structure 20 of a micromechanical sensor 1 according to different embodiments of the present invention, wherein the embodiments shown here are essentially identical to the other embodiments of the present invention. The spring structure 20 is configured such that the first and second spring elements 21, 22 run substantially parallel to each other over certain sections and are coupled to each other over certain sections. A cross-section of the spring structure 20 along a transverse direction 102 is shown here, wherein the transverse direction 102 is oriented, in particular, perpendicular to a principal extension direction of the spring structure 20 (for example, in the case of spring elements 21, 22 designed as spring beams) or perpendicular to a principal alignment line of the spring structure 20 (for example, in the case of a U-shaped spring structure 20).The spring structure 20 comprises, in addition to the first and second spring elements 21, 22, a first and second compensation element 23, 24 for quadrature compensation, wherein the first compensation element 23 is connected to the first spring element 21, and the second compensation element 24 is connected to the second spring element 22. The first spring element 21 has a first spring structure width 210 extending along the transverse direction 102, and the second spring element 22 has a second spring structure width 220 extending along the transverse direction 102. The first compensation element 23 extends in a first sub-region parallel to the transverse direction 102 along a first width 230, and the second compensation element 24 extends in a second sub-region parallel to the transverse direction 102 along a second width 240.According to the invention, preferably the first spring structure width 210 and the first width 230 are of different widths, as are the second spring structure width 220 and the second width 240. Fig. Figure 7 shows a spring structure 20 on the left side according to an embodiment of the present invention, wherein the longitudinal direction 201 and the normal direction 101 are oriented parallel to each other. Furthermore, in Fig. Figure 7 on the right shows an alternative embodiment of the present invention, wherein the longitudinal direction 201 and the normal direction 101 are oriented non-parallel to each other.

[0037] In particular, attaching a compensation element – ​​here the first compensation element 23 – to the inwardly split spring element – ​​here the first spring element 21 – ensures that the upper centroid 215 of the upper part remains above the lower centroid 215' of the lower part. Specifically, "the inwardly split spring element" refers to the spring element which – viewed from a direction parallel to the normal direction 101 towards the substrate 10 – has a flank 211 converging towards the other spring element. Preferably, the first and / or second width 230, 240 of the compensation element is adapted to the trench angle 201' in the manufacturing process to a degree corresponding to the trench angle 201'. Preferably, a basic shape (i.e.,a form of a precursor structure from which the compensation elements 23, 24 are formed in the fourth process step in a depression area 25), a geometric shape (i.e. height parallel to the normal direction 101 and / or width parallel to the main extension plane 100 of the substrate 10) and / or a distance between the first and second spring element 21, 22 adapted such that a wobbling motion is avoided.

[0038] In Fig. Figure 8 shows a spring structure 20 of a micromechanical sensor 1 according to different embodiments of the present invention in a schematic cross-sectional view, wherein the embodiment shown here is essentially identical to the other embodiments of the present invention. Preferably, the structuring of the first layer 301 is carried out such that a trapezoidal depression 25 (with a positive further flank) is created in the first layer 301. This advantageously makes it possible to prevent residues from being trapped in the (by reference numeral 25' on the right side of the) Fig. 8 indicated) area will occur if the trenching process extends into this area.

[0039] In Fig. Figure 9 shows a micromechanical sensor 1 according to an embodiment of the present invention in a schematic cross-sectional view, wherein the embodiment shown here is essentially identical to the other embodiments of the present invention. It is illustrated here that the movable mass element 30 is coupled to the substrate 10 via a spring structure 20, wherein the first and second spring elements 21, 22 run substantially parallel to each other over certain distances and are coupled to each other over certain distances – in particular via coupling elements 26.

[0040] In Fig. Figures 10a to 10f describe a method for manufacturing a micromechanical sensor 1 according to an embodiment of the present invention, wherein, in particular, the embodiment shown here is essentially identical to the other embodiments of the present invention. In a first manufacturing step, a first layer 301 is deposited on a substrate 10, wherein the substrate 10 or the first layer 301 comprises a first sublayer 301' (see Figure 10a to 10f). Fig. 10a). Subsequently, in a second manufacturing step, the first layer 301 is applied to the substrate (see Fig. 10b) a depression area 25 is created in the first layer 301, as in Fig. Figure 10c illustrates this. The structuring of the first layer 301 is achieved, for example, via a time etching process. In a third manufacturing step, a second layer 302 is subsequently deposited, in particular such that the depression area 25 is filled with the material of the second layer 302. In a fourth manufacturing step, the second layer 302 is structured, whereby the spring structure 20 and the mass element 30 are formed from the second layer 302, wherein the spring structure 20 is designed such that a first and second spring element 21, 22 of the spring structure 20 run substantially parallel to each other over certain distances and are coupled to each other over certain distances.Furthermore, in the fourth manufacturing step, during the structuring of the second layer 302, the first compensation element 23 and the second compensation element 24 are formed for quadrature compensation in the depression area 25, so that the first compensation element 23 is connected to the first spring element 21 and the second compensation element 24 is connected to the second spring element 24 (see . Fig. 10e). In a subsequent fifth manufacturing step, the mass element 30 and the spring structure 20 are exposed, with the first layer 301 being at least partially removed. For example, the first layer 301 is removed in a sacrificial layer etching process, such as hydrofluoric acid (HF) gas-phase etching, and the spring structure 20 is exposed.

[0041] In Fig. Figures 11a to 11g describe a method for producing a micromechanical sensor 1 according to an embodiment of the present invention, wherein in particular the embodiment shown here is essentially identical to the other embodiments of the present invention, wherein here a third layer 303 - for example a stop layer 303 - is applied to the first sublayer 301' before or during the first process step (see Figures 11a to 11g). Fig. 11a, Fig. 11b and Fig. 11c). For example, the stop layer is a buried polysilicon layer. The third layer 303 is used in particular to create an L-shaped first and second compensation element 23, 24 (see Fig. 11d, Fig. 11e, Fig. 11f and Fig. 11g).

[0042] In Fig.Figure 12 shows a spring structure 20 of a micromechanical sensor 1 according to different embodiments of the present invention, wherein the embodiment shown here is essentially identical to the other embodiments of the present invention. Here, the first sub-area is indicated by reference numeral 23' and the second sub-area by reference numeral 24'. The first compensation element 23 extends in a further first sub-area (see reference numeral 23") parallel to the transverse direction 102 along a further first width 230', and the second compensation element 24 extends in a further second sub-area (see reference numeral 24") parallel to the transverse direction 102 along a further second width 240'. The further first width 230' is greater than the first spring structure width 210, and the further second width 240' is greater than the second spring structure width 220.In particular, the first and second sub-sections are also referred to as the first and second connection sections, respectively. Here, the first and second connection sections (see reference numerals 23', 24') each have a recess on opposite sides of the first and second spring elements 21, 22. The further first and second sub-sections are also referred to here as the first and second additional sections, respectively. Due to a comparatively wide additional structure, it is advantageously possible, due to a spring stiffness (which preferably scales with the cube of the width), to realize a first and second compensation element that has a comparatively small height (along the normal direction 101) and is therefore particularly easy to manufacture, while still compensating for a quadrature caused by oblique trench angles.

Claims

[1] Micromechanical sensor (1) with a substrate (10) having a principal extension plane (100) and a mass element (30) movable relative to the substrate (10), wherein the movable mass element (30) is coupled to the substrate (10) via a spring structure (20), wherein the spring structure (20) has a first and second spring element (21, 22), wherein the first and second spring element (21, 22) extend substantially parallel to each other over certain distances, characterized by, that the spring structure (20) comprises a first and second compensation element (23, 24) for quadrature compensation, wherein the first compensation element (23) is connected to the first spring element (21), wherein the second compensation element (24) is connected to the second spring element (22), wherein the first spring element (21) has a first spring structure width (210) extending along a transverse direction (102), wherein the second spring element (22) has a second spring structure width (220) extending along the transverse direction (102), wherein the first compensation element (23) extends in a first sub-region parallel to the transverse direction (102) along a first width (230), wherein the first spring structure width (210) and the first width (230) are different, wherein the second compensation element (24) extends in a second sub-region parallel to the transverse direction (102) extends along a second width (240),wherein the second spring structure width (220) and the second width (240) are different, wherein a flank (211) of the first spring element (21) extends along a longitudinal direction (201) towards the substrate (10), -- wherein the first width (230) of the first compensation element (23) and the second width (240) of the second compensation element (24) are substantially equal when the longitudinal direction (201) and a normal direction (101) are oriented parallel to each other, wherein the normal direction (101) is oriented substantially perpendicular to the principal extension plane (100) of the substrate (10), and / or -- wherein the first width (230) of the first compensation element (23) and the second width (240) of the second compensation element (24) are different when the longitudinal direction (201) and the normal direction (101) are oriented non-parallel to each other. [2] Micromechanical sensor (1) according to claim 1, characterized by, that the first compensation element (23) is connected to the first spring element (21) in such a way that the first compensation element (23) is at least partially arranged between the substrate (10) and the first spring element (21), wherein the second compensation element (24) is connected to the second spring element (22) in such a way that the second compensation element (24) is at least partially arranged between the substrate (10) and the second spring element (22). [3] Micromechanical sensor (1) according to any one of the preceding claims, characterized by , that a first cross-sectional area (212) of the first spring element (21) and a second cross-sectional area (222) of the second spring element (22) have the same cross-sectional shape, wherein in particular the first spring structure width (210) and the second spring structure width (220) are equal. [4] Micromechanical sensor (1) according to any one of the preceding claims, characterized by, that the first compensation element (23) extends in a further first sub-area parallel to the transverse direction (102) along a further first width (230'), wherein the second compensation element (24) extends in a further second sub-area parallel to the transverse direction (102) along a further second width (240'), wherein the further first width (230') is greater than the first spring structure width (210) and / or wherein the further second width (240') is greater than the second spring structure width (220). [5] Micromechanical sensor (1) according to claim 4, characterized by , that the first sub-area is mainly located in a region of the first spring element (21) facing the second spring element (22), wherein the second sub-area is mainly located in a region of the second spring element (22) facing the first spring element (21). [6] Method for manufacturing a micromechanical sensor (1) in which a mass element is deflected in a drive direction by a drive movement and a detection deflection in a direction perpendicular to the drive direction is detected, wherein in a first manufacturing step a first layer (301) is deposited on a substrate (10), wherein in a second manufacturing step a depression area (25) is created in the first layer (301), wherein in a third manufacturing step a second layer (302) is deposited on the first layer (301), wherein in a fourth manufacturing step the second layer (302) is structured, wherein a spring structure (20) and a mass element (30) are formed from the second layer (302), wherein the spring structure (20) is designed such that a first and second spring element (21, 22) of the spring structure (20) run substantially parallel to each other over certain distances,wherein in a fifth manufacturing step the mass element (30) and the spring structure (20) are exposed, whereby the first layer (301) is at least partially removed, characterized by , that in the fourth manufacturing step, during the structuring of the second layer (302), a first compensation element (23) and a second compensation element (24) are formed for quadrature compensation in the depression area (25), so that the first compensation element (23) is connected to the first spring element (21) and the second compensation element (24) is connected to the second spring element (22). [7] Method according to claim 6, characterized by, that the spring structure (20) is designed such that the first spring element (21) has a first spring structure width (210) extending along a transverse direction (102) and the second spring element (22) has a second spring structure width (220) extending along the transverse direction (102), wherein in the fourth process step the first compensation element (23) is designed such that the first compensation element (23) extends in a first sub-area parallel to the transverse direction (102) along a first width (230) and the first spring structure width (210) and the first width (230) are different, wherein in the fourth process step the second compensation element (24) is designed such that the second compensation element (24) extends in a second sub-area parallel to the transverse direction (102) along a second width (240) and the second spring structure width (220) and the second width (240) are different. [8] Method according to claim 6 or 7, characterized by , that the first compensation element (23) is connected to the first spring element (21) in an area facing the second spring element (22) and / or that the second compensation element (24) is connected to the second spring element (22) in an area facing the first spring element (21). [9] Method according to any one of claims 6 to 8, characterized by, that in the fourth process step the first spring element (21) is designed such that a flank (211) of the first spring element (21) extends along a longitudinal direction (201) towards the substrate (10), wherein a trench angle (201') is enclosed between the longitudinal direction (201) and a normal direction (101) substantially perpendicular to a principal extension direction (100) of the substrate (10), wherein the spring structure (20) is formed such that the first width (230) and / or a further first width (230') of the first compensation element (23) is determined by the trench angle (201') and / or that the second width (240) and / or a further second width (240') of the second compensation element (24) is determined by the trench angle (201').

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