Stops as getters to stabilize the cavern pressure

Abstract

Method for producing a micromechanical component (1) with a substrate (3) and with a cap (7) connected to the substrate (3) and enclosing a first cavity (5) with the substrate (3), wherein a first pressure prevails in the first cavity (5) and a first gas mixture with a first chemical composition is enclosed, wherein -- in a first method step (101), an access opening (11) connecting the first cavity (5) to an environment (9) of the micromechanical component (1) is formed in the substrate (3) or in the cap (7), wherein -- in a second method step (102), the first pressure and / or the first chemical composition in the first cavern (5) is adjusted, wherein -- in a third method step (103), the access opening (11) is closed by introducing energy or heat into an absorbing part of the substrate (3) or the cap (7) with the aid of a laser, characterized in that -- in a fourth method step (104), the first pressure in the first cavity (5) is further adjusted, wherein a mechanical impact is brought about between a first structure of the micromechanical component (1) and a second structure of the micromechanical component (1), wherein the surface of at least part of the first structure is enlarged by means of the mechanical impact and / or the surface of at least part of the second structure is enlarged, wherein the first pressure is reduced by means of the enlarged surface of at least part of the first structure and / or by means of the enlarged surface of at least part of the second structure, wherein the pressure reduction occurs in that, during the mechanical impact of oxidized silicon structures, non-oxidized silicon surfaces are exposed, which act as getters,which results in a pressure reduction in the cavern due to the binding of gas quantities released in the cavern.

Description

State of the art

[0001] The invention is based on a method according to the preamble of claim 1.

[0002] Such a method is known from WO 2015 / 120939 A1. If a specific internal pressure is desired in a cavity of a micromechanical component or if a gas mixture with a specific chemical composition is to be enclosed in the cavity, the internal pressure or the chemical composition is often adjusted during the capping of the micromechanical component or during the bonding process between a substrate wafer and a cap wafer. During capping, for example, a cap is connected to a substrate, whereby the cap and the substrate together enclose the cavity. By adjusting the atmosphere or the pressure and / or the chemical composition of the gas mixture present in the environment during capping, the specific internal pressure and / or the specific chemical composition in the cavity can be adjusted.

[0003] The method known from WO 2015 / 120939 A1 allows for the targeted adjustment of an internal pressure in a cavity of a micromechanical component. This method makes it possible, in particular, to produce a micromechanical component with a first cavity, wherein a first pressure and a first chemical composition can be adjusted in the first cavity, which differ from a second pressure and a second chemical composition at the time of encapsulation.

[0004] In the method for the targeted adjustment of internal pressure in a cavity of a micromechanical component according to WO 2015 / 120939 A1, a narrow access channel to the cavity is created in the cap or cap wafer, or in the substrate or sensor wafer. The cavity is then flooded with the desired gas and the desired internal pressure via the access channel. Finally, the area around the access channel is locally heated using a laser; the substrate material liquefies locally and, upon solidification, hermetically seals the access channel.

[0005] The quality of gyroscopes is extremely sensitive to the internal cavern pressure. Furthermore, to achieve high offset performance from gyroscopes over their lifetime, the quality must be as stable as possible, since any deviation in the quality from the value incorporated into the calibration parameters during calibration leads to an offset of the gyroscope. In order to achieve the highest and most stable quality over the lifetime of the gyroscopes, it is therefore essential to stabilize or keep the internal pressure of the gyroscope cavity constant over the lifetime of the gyroscopes. In the case of gyroscopes with a high quality (i.e. low internal cavern pressure), an increase in the internal pressure is often observed after HT storage (storage periods at comparatively high temperatures). This increase is caused by outgassing or gas diffusion into the cavern.

[0006] Further methods for the targeted adjustment of an internal pressure in a cavity of a micromechanical component are known from US 8,546,928 B2, US 2015 / 0158720 A1 and US 8,513,747 B1.

[0007] Further disclosures can be found in the documents US 20110114840A, DE 102014202801A1 and US 2014 / 0022718 A1. Disclosure of the invention

[0008] It is an object of the present invention to provide a method for producing a micromechanical component that is mechanically robust and has a long service life compared to the prior art, in a simple and cost-effective manner compared to the prior art. Furthermore, it is an object of the present invention to provide a micromechanical component that is compact, mechanically robust and has a long service life compared to the prior art. According to the invention, this applies in particular to a micromechanical component with a (first) cavity. With the method according to the invention and the micromechanical component according to the invention, it is also possible to realize a micromechanical component in which a first pressure and a first chemical composition can be set in the first cavity and a second pressure and a second chemical composition can be set in a second cavity.For example, such a method is provided for the production of micromechanical components for which it is advantageous if a first pressure is enclosed in a first cavity and a second pressure in a second cavity, wherein the first pressure should be different from the second pressure. This is the case, for example, when a first sensor unit for measuring the rotation rate and a second sensor unit for measuring acceleration are to be integrated in a micromechanical component. For example, the first cavity and the second cavity are separated from one another only by a bonding bridge. In particular, the object of the present invention is to enable high quality over the lifetime of the micromechanical component.

[0009] The object is achieved in that -- in a fourth method step, the first pressure in the first cavity is further adjusted, wherein a mechanical impact is brought about between a first structure of the micromechanical component and a second structure of the micromechanical component, wherein with the aid of the mechanical impact the surface of at least part of the first structure is enlarged and / or the surface of at least part of the second structure is enlarged, wherein with the aid of the enlarged surface of at least part of the first structure and / or with the aid of the enlarged surface of at least part of the second structure the first pressure is reduced.

[0010] This provides a simple and cost-effective method for producing a micromechanical component with which the first pressure in the first cavity, in particular when the first cavity is a yaw rate sensor cavity, can be kept essentially constant or stabilized over the lifetime, or with which the first pressure can be further reduced after a provisional setting of the first pressure. This is achieved, for example, in that small amounts of gas that outgas from the materials within the first cavity over the lifetime or that enter the first cavity through gas diffusion, for example through the substrate or through the cap or through a bonding frame or bonding bridge between the first cavity and the second cavity, are bound by the enlarged surface or by the additionally provided surface or by the additional material introduced into the cavity.

[0011] A further advantage of the method according to the invention is that a micromechanical component with a specifically adjusted quality, in particular with a high quality compared to the prior art, can be provided. In this way, for example, a high-quality system can be provided. In particular, by repeatedly "moving the first structure and the second structure to the stop," a significantly increased quality of yaw rate sensors is possible compared to the prior art.

[0012] Advantageously, with the help of the first structure arranged in the first cavity and with the help of the second structure arranged in the first cavity, the internal pressure in the cavity can be specifically adjusted for each component in a simple and cost-effective manner, in particular also after the bonding process between the substrate wafer and the cap wafer. This is particularly advantageous because it also makes it possible to counteract an increase in the internal pressure due to outgassing after the bonding process by specifically increasing the surface area of ​​the first structure and / or the second structure. Furthermore, it is advantageously possible to achieve a desired vibration quality, i.e. an increased vibration quality, for each component, by specifically adjusting the first pressure, i.e. by specifically reducing the first pressure, in the first cavity.Furthermore, the micromechanical component according to the invention advantageously makes it possible to compensate for or reduce pressure variations between several micromechanical components according to the invention by controlled reduction of the internal pressures in the cavities of several micromechanical components according to the invention. This enables a significant reduction in the quality variations between the various micromechanical components of a wafer and thus a reduction in unwanted fluctuations in the system parameters of the micromechanical components and a reduction in the effect of undesired process variation.

[0013] According to the invention, enlarging the surface of at least part of a structure preferably means separating at least part of the structure from the structure. However, only partially separating at least part of the structure from the structure or even roughening the surface of the structure is also understood as enlarging the surface in the sense of the present invention.

[0014] In the context of the present invention, the term “micromechanical component” is to be understood as encompassing both micromechanical components and microelectromechanical components.

[0015] The present invention is preferably intended for the production of a micromechanical component with one cavity. However, the present invention is also intended, for example, for a micromechanical component with two cavities or with more than two, ie, three, four, five, six, or more than six, cavities.

[0016] The access opening is preferably closed by introducing energy or heat into a part of the substrate or the cap which absorbs this energy or heat, using a laser. In this case, energy or heat is preferably introduced one after the other into the absorbing part of the substrate or the cap of a plurality of micromechanical components, which are manufactured together on a wafer, for example. Alternatively, however, a parallel introduction of the energy or heat into the respective absorbing part of the substrate or the cap of a plurality of micromechanical components is also provided, for example using a plurality of laser beams or laser devices. Alternatively, the invention also provides for the access opening to be closed using an oxide reseal process or an oxide reclosure process. In this case, the oxide reseal process orThe oxide reseal process, for example, is an alternative sealing process to the laser reseal process or the laser reseal process, in which the subsequent opening of the cavern is hermetically sealed with an oxide lid, which is grown at low ambient pressure.

[0017] Advantageous embodiments and further developments of the invention can be found in the dependent claims and the description with reference to the drawings.

[0018] According to a preferred development, it is provided that the cap with the substrate encloses a second cavity, wherein a second pressure prevails in the second cavity and a second gas mixture with a second chemical composition is enclosed.

[0019] According to a preferred development, the fourth method step is performed after the third method step. This advantageously allows the first pressure to be adjusted, further adjusted, or reduced after the bonding process.

[0020] According to a preferred development, the mechanical impact is achieved by applying a third potential to a third structure of the micromechanical component that differs from a first electrical potential applied to the first structure and from a second electrical potential applied to the second structure, wherein a first potential difference is provided between the first electrical potential and the second electrical potential, wherein the first potential difference is substantially equal to zero, wherein a second potential difference is provided between the second electrical potential and the third electrical potential. This advantageously enables the mechanical impact between the first structure and the second structure, wherein substantially no electrostatic forces act between the first structure and the second structure.This advantageously allows the first structure and the second structure to strike each other without sticking to each other.

[0021] According to a preferred development, the mechanical impact is achieved by applying a first electrical potential to the first structure and a second electrical potential to the second structure, with a third potential difference being provided between the first electrical potential and the second electrical potential. This advantageously enables the mechanical impact to be enabled by means of electrostatic forces acting on the first structure and the second structure, and thus can be advantageously integrated into micromechanical components known from the prior art and their control and operating methods.

[0022] According to a preferred development, it is provided that the first electrical potential is provided so as to be variable over time and / or the second electrical potential is provided so as to be variable over time. According to a preferred development, it is provided that the first electrical potential is provided so as to be constant over time and / or the second electrical potential is provided so as to be constant over time. According to a preferred development, it is provided that the potential difference is provided so as to be variable over time. This advantageously makes it possible for the electrostatic forces acting on the first structure and on the second structure to be constant over time and / or variable over time. It is also advantageously possible for the first electrical potential and the second electrical potential to be adjustable in comparison to other electrical potentials. Furthermore, it is thus advantageously possible for the second structure to be driven resonantly orcan be set into a resonant oscillation. This makes mechanical striking particularly easy.

[0023] According to the invention, silicon is exposed by mechanical impact. This advantageously eliminates the need to introduce additional material into the first cavity, but rather allows the sensor material silicon, for example, to be used as a kind of getter by exposing non-oxidized silicon surfaces by striking oxidized silicon surfaces against each other.

[0024] According to a preferred development, it is provided that, in a fifth method step, a first material of the first structure and / or a second material of the second structure and / or a third material of the third structure is deposited on the substrate or on the cap. This advantageously enables the first material of the first structure and / or the second material of the second structure and / or the third material of the third structure to be deposited on the substrate or the cap in parallel with another material for another structure.

[0025] According to a preferred development, the fifth method step is performed prior to the first method step. This advantageously allows the first material of the first structure and the second material of the second structure and / or the third material of the third structure to be deposited prior to the bonding of the substrate to the cap.

[0026] According to a preferred development, the first material and / or the second material and / or the third material and / or the further material is germanium. This advantageously enables the first material of the first structure and / or the second material of the second structure and / or the third material of the third structure to be deposited and structured together with the germanium for the bonding process when using germanium for the bonding process, for example, as a bonding frame.

[0027] According to a preferred development, the first material and the second material and / or the third material are deposited and structured together with the additional material. This advantageously enables the deposition and structuring of the first material and the second material and / or the third material to be easily and cost-effectively integrated into an existing manufacturing process.

[0028] According to a preferred development, the first material and the second material and / or the third material are deposited after the additional material. This makes it possible, for example, to avoid structuring a first region comprising the first material and a second region comprising the second material and / or a third region comprising the third material.

[0029] A further subject matter of the present invention is a micromechanical component having a substrate and a cap which is connected to the substrate and encloses a first cavity with the substrate, wherein a first pressure prevails in the first cavity and a first gas mixture having a first chemical composition is enclosed, wherein the substrate or the cap comprises a closed access opening, wherein the micromechanical component comprises a first structure arranged in the first cavity and a second structure arranged in the first cavity for bringing about a mechanical impact between the first structure and the second structure for enlarging the surface area of ​​at least part of the first structure and / or for enlarging the surface area of ​​at least part of the second structure for reducing the first pressure.This advantageously provides a compact, mechanically robust, and cost-effective micromechanical component with a set first pressure. The aforementioned advantages of the method according to the invention also apply accordingly to the micromechanical component according to the invention.

[0030] According to the invention, the enlarged surface of at least part of the first structure and / or the enlarged surface of at least part of the second structure at least partially comprises silicon. This advantageously makes it possible to eliminate the need to introduce additional material into the first cavity, but rather to utilize the sensor material silicon, for example, by exposing non-oxidized silicon surfaces by striking oxidized silicon surfaces against each other, like a type of getter.

[0031] According to a preferred development, it is provided that the micromechanical component comprises a third structure which is rigid with respect to the substrate or with respect to the cap and arranged in the first cavity.

[0032] According to a preferred embodiment, the first structure and / or the second structure and / or the third structure comprise silicon and / or germanium. This advantageously enables the first structure and the second structure to be manufactured using standard methods of semiconductor layer technology.

[0033] According to a preferred development, the first structure is arranged rigidly and the second structure is arranged movably relative to the substrate or relative to the cap, or the first structure is arranged movably and the second structure is arranged movably relative to the substrate or relative to the cap. Thus, the first structure and the second structure can be implemented particularly advantageously in different embodiments of micromechanical components.

[0034] According to a preferred development, a protective structure is arranged between the first structure and a sensor core arranged in the first cavity, as well as between the second structure and the sensor core. This advantageously enables particles separated from the first structure and / or the second structure by mechanical impact to be kept away from the sensor core, thus reducing the likelihood of short circuits triggered by the particles in the region of the sensor core.

[0035] According to a preferred development, the cap encloses a second cavity with the substrate, wherein a second pressure prevails in the second cavity and a second gas mixture with a second chemical composition is enclosed. This advantageously provides a compact, mechanically robust, and cost-effective micromechanical component with a set first pressure and a second pressure.

[0036] According to a preferred development, the first pressure is lower than the second pressure, with a first sensor unit for measuring the yaw rate being arranged in the first cavity and a second sensor unit for measuring acceleration being arranged in the second cavity. This advantageously provides a mechanically robust micromechanical component for measuring yaw rate and acceleration with optimal operating conditions for both the first sensor unit and the second sensor unit. Short description of the drawings Fig. 1 shows a schematic representation of a micromechanical component with an open access opening according to an exemplary embodiment of the present invention. Fig. 2 shows a schematic representation of the micromechanical component according to Fig. 1 with closed access opening. Fig. 3 shows a schematic representation of a method for producing a micromechanical component according to an exemplary embodiment of the present invention. Embodiments of the invention

[0037] In the various figures, identical parts are always provided with the same reference symbols and are therefore usually named or mentioned only once.

[0038] In Fig. 1 and Fig. 2 is a schematic representation of a micromechanical component 1 with open access opening 11 in Fig. 1 and with closed access opening 11 in Fig. 2 according to an exemplary embodiment of the present invention. Here, the micromechanical component 1 comprises a substrate 3 and a cap 7. The substrate 3 and the cap 7 are connected to each other, preferably hermetically, and together enclose a first cavity 5. For example, the micromechanical component 1 is designed such that the substrate 3 and the cap 7 additionally enclose a second cavity. The second cavity is in Fig. 1 and in Fig. 2 is not shown.

[0039] For example, in the first cavern 5, especially as in Fig. 2, a first pressure. In addition, a first gas mixture with a first chemical composition is enclosed in the first cavity 5. Furthermore, a second pressure prevails, for example, in the second cavity, and a second gas mixture with a second chemical composition is enclosed in the second cavity. Preferably, the access opening 11 is arranged in the substrate 3 or in the cap 7. In the present embodiment, the access opening 11 is arranged, for example, in the cap 7. According to the invention, however, it can also be provided alternatively that the access opening 11 is arranged in the substrate 3.

[0040] For example, it is provided that the first pressure in the first cavern 5 is lower than the second pressure in the second cavern. For example, it is also provided that in the first cavern 5 a Fig. 1 and Fig. 2 not shown first micromechanical sensor unit for angular rate measurement and in the second cavern a Fig. 1 and Fig. 2 not shown second micromechanical sensor unit for acceleration measurement are arranged.

[0041] In Fig. 3 shows a schematic representation of a method for producing the micromechanical component 1 according to an exemplary embodiment of the present invention. -- in a first method step 101, the access opening 11, in particular a narrow one, connecting the first cavity 5 with an environment 9 of the micromechanical component 1 is formed in the substrate 3 or in the cap 7. Fig. 1 shows an example of the micromechanical component 1 after the first method step 101. In addition, -- in a second method step 102, the first pressure and / or the first chemical composition in the first cavern 5 is adjusted or the first cavern 5 is flooded with the desired gas and the desired internal pressure via the access channel. Furthermore, for example, -- in a third method step 103, the access opening 11 is closed by introducing energy or heat into an absorbing part of the substrate 3 or the cap 7 using a laser. Alternatively, it is also provided, for example, that -- in the third method step 103, the area around the access channel is only locally heated, preferably by a laser, and the access channel is hermetically sealed. Thus, it is advantageously possible to provide the method according to the invention with energy sources other than a laser for closing the access opening 11. Fig. 2 shows an example of the micromechanical component 1 after the third method step 103.

[0042] After the third method step 103, in a Fig. 2, mechanical stresses occur in the lateral region 15 shown by way of example on a surface of the cap 7 facing away from the cavity 5, as well as in the depth perpendicular to a projection of the lateral region 15 onto the surface, i.e. along the access opening 11 and in the direction of the first cavity 5, of the micromechanical component 1. These mechanical stresses, in particular local mechanical stresses, prevail in particular at and in the vicinity of an interface between a material region 13 of the cap 7, which changes into a liquid state of aggregation in the third method step 103 and, after the third method step 103, changes into a solid state of aggregation and closes the access opening 11, and a residual region of the cap 7 remaining in a solid state of aggregation during the third method step 103. In this case, Fig. 2 the material region 13 of the cap 7 closing the access opening 11 is to be regarded or shown schematically only, in particular with regard to its lateral extension or shape, in particular running parallel to the surface, and in particular with regard to its extension or configuration perpendicular to the lateral extension, in particular running perpendicular to the surface.

[0043] As in Fig. 3 shown as an example, additionally -- in a fourth method step 104, the first pressure in the first cavity 5 is further adjusted, wherein a mechanical impact is brought about between a first structure of the micromechanical component 1 and a second structure of the micromechanical component 1. In this case, the surface of at least part of the first structure is enlarged and / or the surface of at least part of the second structure is enlarged, for example, by means of the mechanical impact. Thus, the first pressure is reduced, for example, by means of the enlarged surface of at least part of the first structure and / or by means of the enlarged surface of at least part of the second structure.

[0044] For example, silicon surfaces are exposed using mechanical impact. This is intended, for example, as follows: -- The first structure comprises a first stop and the second structure comprises a second stop, wherein the first stop and the second stop are designed such that the first structure and the second structure do not stick to one another. In other words, the first stop and the second stop are designed such that the first stop and the second stop act as "regular" stops and prevent the first structure from sticking to the second structure, for example the movable structure. In this case, for example, the first stop and the second stop additionally have the function of binding released gas quantities as getters. In this case, for example, protective structures are useful which prevent particles that are detached from or generated by the first structure and / or the second structure upon impact from causing short circuits in the sensor core. -- The first structure and the second structure are spatially separated from the sensor core such that the sensor core is arranged in a first subcavern of the first cavern 5 and the first structure and the second structure are arranged in a second subcavern of the first cavern 5. In this case, it is provided, for example, that the first subcavern and the second subcavern are connected to one another by at least one channel, in particular a thin channel. In this case, it is provided, in particular, that the channel is designed such that the channel has a minimal extension, wherein a maximum extension of the first subcavern essentially comprises 10, 100, 1000, or 10,000 times the minimal extension. For example, it is provided that the first structure and the second structure are provided as "extra" stops, which e.g.are briefly knocked together by applying a voltage during each ramp-up of the sensor and which are connected to the cavern volume of the first cavern 5 via thin channels. Here, it is provided that a gas exchange with the first cavern 5 or with the cavern interior volume is possible through the channel(s) or through the channels or through the thin channels. For example, however, it is additionally provided that particles which are detached from or form on the first structure and / or the second structure as a result of the mechanical impact do not get into or to the sensor core and lead to one or more short circuits there. In particular, it is provided that silicon surfaces are exposed as a result of the mechanical impact or that particles comprising silicon surfaces are detached from the first structure and / or the second structure. -- The first structure and the second structure are designed such that a movement leading to the mechanical striking is carried out essentially perpendicular to a surface of the substrate 3 or the cap 7 facing away from the first cavity 5 by the first structure and / or by the second structure. For example, it is additionally or alternatively provided that the first structure and the second structure are designed such that a movement leading to the mechanical striking is carried out essentially parallel to the surface of the substrate 3 or the cap 7 by the first structure and / or by the second structure. In other words, for example, the first structure and the second structure are designed such that the mechanical striking is carried out in the z-direction (perpendicular to the wafer surface) and / or in the x- or y-direction.

[0045] Furthermore, it is provided, for example, that in a fifth method step, a first material of the first structure and / or a second material of the second structure and / or a third material of the third structure is deposited on the substrate 3 or on the cap 7. In this case, for example, the first material and the second material and / or the third material are deposited and structured together with another material. For example, the other material comprises germanium, which is applied to the cap 7 for the bonding process before the first cavity 5 is trenched.

[0046] For example, it is alternatively also provided that the first material and the second material and / or the third material are deposited after the further material, for example after the deposition of the bond frame comprising germanium and after the trenching of the cavity, over the entire surface of the cavity interior or on a surface of the substrate 3 facing the first cavity 5 and / or on a surface of the cap 7 facing the first cavity 5. Advantageously, no further lithography step for structuring the first material and the second material and / or the third material is necessary.

Claims

[1] Method for producing a micromechanical component (1) with a substrate (3) and with a cap (7) connected to the substrate (3) and enclosing a first cavity (5) with the substrate (3), wherein a first pressure prevails in the first cavity (5) and a first gas mixture with a first chemical composition is enclosed, wherein -- in a first method step (101), an access opening (11) connecting the first cavity (5) to an environment (9) of the micromechanical component (1) is formed in the substrate (3) or in the cap (7), wherein -- in a second method step (102), the first pressure and / or the first chemical composition in the first cavern (5) is adjusted, wherein -- in a third method step (103), the access opening (11) is closed by introducing energy or heat into an absorbing part of the substrate (3) or the cap (7) using a laser, characterized by , that -- in a fourth method step (104), the first pressure in the first cavity (5) is further adjusted, wherein a mechanical impact is brought about between a first structure of the micromechanical component (1) and a second structure of the micromechanical component (1), wherein the surface of at least part of the first structure is enlarged by means of the mechanical impact and / or the surface of at least part of the second structure is enlarged, wherein the first pressure is reduced by means of the enlarged surface of at least part of the first structure and / or by means of the enlarged surface of at least part of the second structure, wherein the pressure reduction occurs in that, during the mechanical impact of oxidized silicon structures, non-oxidized silicon surfaces are exposed, which act as getters,which results in a reduction in pressure in the cavern due to the binding of gas quantities released in the cavern. [2] Method according to claim 1, wherein the mechanical striking is achieved by applying to a third structure of the micromechanical component (1) a third potential that differs from a first electrical potential applied to the first structure and from a second electrical potential applied to the second structure, wherein a first potential difference is provided between the first electrical potential and the second electrical potential, wherein the first potential difference is substantially equal to zero, wherein a second potential difference is provided between the second electrical potential and the third electrical potential, this enabling the first and second structures to strike each other without adhesion [3] Method according to claim 1, wherein the mechanical striking is achieved by applying a first electrical potential to the first structure and a second electrical potential to the second structure, wherein a third potential difference is provided between the first electrical potential and the second electrical potential, which is used to carry out a control or operating method. [4] Method according to one of the preceding claims, wherein in a fifth method step, wherein the fifth method step is carried out before the first method step, a first material of the first structure and / or a second material of the second structure and / or a third material of the third structure is deposited on the substrate (3) or on the cap (7). [5] Micromechanical component (1) with a substrate (3) and with a cap (7) connected to the substrate (3) and enclosing a first cavity (5) with the substrate (3), wherein a first pressure prevails in the first cavity (5) and a first gas mixture with a first chemical composition is enclosed, wherein the substrate (3) or the cap (7) comprises a closed access opening (11), characterized byin that the micromechanical component (1) comprises a first structure arranged in the first cavity (5) and a second structure arranged in the first cavity (5) for bringing about a mechanical impact between the first structure and the second structure in order to enlarge the surface area of ​​at least part of the first structure and / or to enlarge the surface area of ​​at least part of the second structure in order to reduce the first pressure, wherein the mechanical impact is initiated by means of an electrical potential, wherein the pressure reduction occurs in that, during the mechanical impact of oxidized silicon structures, non-oxidized silicon surfaces are exposed, which act as getters, whereby a pressure reduction in the cavity is achieved due to the binding of gas quantities released in the cavity. [6] Micromechanical component (1) according to claim 5, wherein the micromechanical component (1) comprises a third structure which is rigid with respect to the substrate (3) or with respect to the cap (7) and arranged in the first cavity (5), said third structure becoming effective in the context of the mechanical striking. [7] Micromechanical component (1) according to claim 5 or 6, wherein the first structure and / or the second structure and / or the third structure comprises silicon and / or germanium. [8] Micromechanical component (1) according to claim 5, 6 or 7, wherein the first structure is arranged rigidly and the second structure is arranged movable relative to the substrate (3) or relative to the cap (7) or the first structure is arranged movable and the second structure is arranged movable relative to the substrate (3) or relative to the cap (7). [9] Micromechanical component (1) according to claim 5, 6, 7 or 8, wherein a protective structure is arranged between the first structure and a sensor core arranged in the first cavity (5) and between the second structure and the sensor core. [10] Micromechanical component (1) according to claim 5, 6, 7, 8 or 9, wherein the cap (7) with the substrate (3) encloses a second cavity, wherein a second pressure prevails in the second cavity and a second gas mixture with a second chemical composition is enclosed. [11] Micromechanical component (1) according to claim 5, 6, 7, 8, 9 or 10, wherein the first pressure is lower than the second pressure, wherein a first sensor unit for measuring the rotation rate is arranged in the first cavity (5) and a second sensor unit for measuring the acceleration is arranged in the second cavity.

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