MEMS mirror array module

Abstract

The invention relates to a MEMS mirror array module (100) for use in a lithographic projection exposure apparatus (1). A MEMS mirror array module (100) according to the invention comprises a MEMS mirror array structure (110) on a rewiring substrate (120), and an interface element (140) for securing the MEMS mirror array module (100) to a higher-level component, the interface element being on a side of the rewiring substrate (120) remote from the MEMS mirror array structure (110). A cavity (150) is provided between the rewiring substrate (120) and the interface element (140), a wall (151) of which is connected at least to the rewiring substrate (120) in a thermally conductive manner, and a fluid line (200) for conducting a heat transfer fluid extends along the wall (151) in a thermally conductive contact therewith, at least one end of the fluid line passes through the interface element (140) and is led out of the MEMS mirror array module (100).

Description

[0001] This application claims priority to German patent application 10 2023 118 233.1, filed on July 11, 2023, the contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to a MEMS mirror array module for photolithography projection exposure equipment. Background Technology

[0003] Photolithography is used to manufacture microstructured components, such as integrated circuits. The projection exposure equipment used in this process includes an illumination system and a projection system. Using the projection system, an image of a mask (also called a photomask) illuminated by the illumination system is projected onto a substrate (such as a silicon wafer) to reduce the size of the former. The substrate is coated with a photosensitive layer and arranged in the image plane of the projection system so that the mask structure can be transferred onto the photosensitive coating of the substrate.

[0004] Typically, in illumination systems (especially projection exposure equipment designed for the EUV range, i.e., exposure wavelengths from 5 nm to 30 nm), two faceted mirrors are arranged in the beam path between the actual exposure radiation source and the mask to be illuminated, and these mirrors allow for radiation homogenization in a manner substantially equivalent to that of a fly-eye condenser. The faceted mirror closer to the exposure radiation source in the beam path is usually a so-called field faceted mirror, while the other faceted mirror is a so-called pupil faceted mirror.

[0005] In order to produce different intensity and / or incident angle distributions during mask illumination, it is known that at least one of two faceted mirrors (particularly the facets of a field faceted mirror) is formed by one or more individually electromechanically pivotable micromirrors. The same is disclosed accordingly, for example, in WO 2012 / 130768 A2.

[0006] In order to achieve the small size of each micromirror, the known approach is to design the micromirror group in the form of a so-called MEMS mirror array, that is, a mirror array made of microelectromechanical systems (MEMS).

[0007] In a MEMS mirror array, multiple small mirror elements are each mounted to be individually movable relative to a mounting base. For each mirror element, at least one actuator is provided, enabling adjustment of the mirror element along separately predefined degrees of freedom. The mirror elements are typically pivotable about two axes that are perpendicular to each other and parallel to the base; in this case, sufficient actuators are then provided to enable the mirror elements to pivot precisely about these axes independently of each other. Sensors can also be provided for each mirror element, enabling determination of the mirror element's position relative to the base, thereby allowing monitoring of mirror alignment. A particularly advantageous embodiment of the mirrors in a MEMS mirror array is described in DE 10 2015 204 874 A1.

[0008] A method for fabricating micromirrors or MEMS mirror arrays comprising multiple such micromirrors is disclosed in DE 10 2015 220 018 A1, along with further details relating to possible configurations of the micromirrors.

[0009] In the case of the intended use in photolithography mentioned at the beginning, a MEMS mirror array is used in the region of the illumination system. In this case, high-energy radiation is incident on the surface of the mirrors of the MEMS mirror array and reflected there in the corresponding desired direction; however, some of the incident radiation is also absorbed and thus introduced into the MEMS structure as heat. Coupled with the unavoidable heat input from the electronic components of the MEMS structure, and the fact that the MEMS mirror array of the photolithography illumination system (especially in the EUV range) is regularly arranged in a vacuum to exclude convective heat dissipation, in principle, high temperatures may occur in the MEMS mirror array during the operation of such an illumination system, which may shorten the lifespan of the reflective coating and the electronic and electromechanical components. Summary of the Invention

[0010] The problem to be solved by the present invention is to develop a MEMS mirror array module in which the disadvantages known in the prior art no longer occur or only to a reduced extent.

[0011] This problem is solved by the MEMS mirror array module as described in claim 1. The dependent claims relate to advantageous improvements.

[0012] Therefore, the present invention relates to a MEMS mirror array module, comprising a MEMS mirror array structure disposed on a redistribution substrate, and an interface element disposed on the side of the redistribution substrate opposite to the MEMS mirror array structure for fixing the MEMS mirror array module to a higher-level component, wherein a cavity is provided between the redistribution substrate and the interface element, and the wall of the cavity is at least thermally connected to the redistribution substrate, and a fluid conduit for conducting heat transfer fluid is guided along the wall in a thermally conductive contact manner, at least one end of which is led out from the MEMS mirror array module through the interface element.

[0013] First, let me explain some of the terms used in connection with this invention.

[0014] A substance or material is "thermally conductive" if it is suited in principle to transfer heat in the absence of simultaneous mass transfer, wherein thermal conductivity is given at any temperature difference and at any temperature under the intended operating conditions. This means that the thermal conductivity at 0°C is greater than or equal to... Preferably greater than or equal to And at least for all expected operating temperatures occurring in the substance, the temperature does not drop below At that time, matter was considered to be thermally conductive.

[0015] This invention is based on a non-atypical known construction of a MEMS mirror array module. It includes a MEMS structure forming an actual MEMS mirror array and having multiple mirror elements, each of which is pivotable about at least one axis, typically about two axes extending perpendicularly to each other, is provided with a reflective coating, and can be pivoted individually by an actuator that is also part of the MEMS mirror array structure. Sensors for measuring the corresponding angular positions of the individual mirror elements are also provided. The MEMS mirror array structure may additionally include application-specific integrated circuits (ASICs), such as circuitry for the targeted pivot positions of the individual mirror elements. Additional sensors, such as temperature sensors, may also be formed and provided as ASICs.

[0016] The MEMS mirror array structure is arranged on a redistribution substrate and securely connected to it. The redistribution substrate, typically fabricated on a silicon substrate, is used for bonding the MEMS mirror array structure (i.e., contact of the electrical contacts) and for converting the contacts on the MEMS mirror array structure into larger contacts to which control and power cables can be inserted or soldered. Furthermore, the structural integrity of the MEMS mirror array structure is ensured by the redistribution substrate, even under mechanical loads. Finally, the redistribution substrate also serves to dissipate heat from the MEMS structure; therefore, it is, in principle, thermally conductive.

[0017] An interface element is disposed on the side of the redistribution substrate facing away from the MEMS mirror array structure. This interface element allows the MEMS mirror array module to be mounted to a higher-level assembly, such as a carrier plate for a faceted mirror assembly in a projection exposure apparatus. In this case, the interface element can be implemented as needed, particularly considering the intended use and the connection technology available in the process. In principle, the material of the interface element can also be selected as needed. However, at least in the prior art, thermally conductive materials are often used to allow heat to be conducted from the MEMS mirror array structure through the redistribution substrate and the interface element to the higher-level assembly. Power and control lines for the MEMS mirror array structure are also typically routed through the interface element to the higher-level assembly for proper connection there.

[0018] The objective is to provide a cavity between a redistribution substrate and interface elements, where it is important that the walls of the cavity are thermally connected to the redistribution substrate. In other words, in the presence of a temperature difference, heat should therefore flow from the redistribution substrate into the walls of the cavity, where the redistribution substrate itself may also form part of the cavity walls. The cavity can also be used for various purposes, such as for connecting control lines and power lines to a MEMS mirror array structure. However, according to the invention, in any case, a fluid conduit for guiding the heat transfer fluid is specified to be guided along the wall. In this case, the heat transfer fluid guided through the fluid conduit is in thermally conductive contact, i.e., the fluid conduit itself and the contact area between the fluid conduit and the wall are both thermally conductive. Therefore, in the presence of a temperature difference between the wall portion adjacent to the fluid conduit and the heat transfer fluid guided in the latter, heat conduction occurs from the wall to the heat transfer fluid.

[0019] At least one end of the fluid line is guided out of the MEMS mirror array module via an interface element. In this case, the fluid line may protrude from or terminate in a region of the outer surface of the interface element. The fluid line may be further configured to enable direct connection to another fluid line segment. For this purpose, the fluid line may include portions of a fluid coupling device in the region of the outer surface of the interface element, or may be suitably designed for simple and tight connection to another fluid line segment, for example, including a flange.

[0020] Due to the innovative configuration of the MEMS mirror array module, heat introduced or generated in the MEMS mirror array structure can be transferred solely through thermal conduction via the rewiring substrate, the thermally connected cavity walls, and the fluid lines adjacent to the thermally conductive walls to the heat transfer fluid located in the fluid lines. If the temperature of the heat transfer fluid in the fluid lines in the region adjacent to the walls is lower than the temperature of the MEMS mirror array structure, a corresponding heat flow exists, and the heat dissipates from the MEMS mirror array structure.

[0021] To ensure permanent thermally conductive contact between the fluid line and the wall, the fluid line can be integrally joined to the wall. To further ensure good heat conduction between the wall and the fluid line, the material used for the integral joint is preferably also thermally conductive. In this case, the integral joint should be designed or the materials selected so that the integral joint will not fail due to stress at the joint caused by the difference in thermal expansion coefficients between the fluid line and the components forming the cavity wall. Needless to say, the stresses in question can also be reduced through structural measures and by matching the thermal expansion coefficients of the fluid line and the components forming the cavity wall.

[0022] The material used for integral bonding can be solder, as can be immediately seen, where fluid lines are fixed to the wall by welding. Brazing with high-melting-point solder at temperatures above 450°C is particularly preferred. The use of appropriate solder ensures that the integral bonding does not fail or soften at the temperature typically expected at the joint during the desired heat conduction.

[0023] In an alternative, a thermally conductive adhesive can be used as the integral bonding material. To ensure the thermal conductivity, the adhesive may, for example, comprise silver particles and / or hexagonal boron nitride particles.

[0024] The desired integral bonding can also be achieved by sintering with a thermally conductive material. In this case, silver sintering is particularly preferred because it results in good thermal conductivity.

[0025] Preferably, the metallic coating is applied to at least the portion of the wall along its fluid-guiding conduit, particularly if the integral joint should be achieved by welding or sintering, but the wall in the area adjacent to the fluid conduit is not directly suitable for this purpose. The metallic material used for the coating can be selected specifically with regard to the solder or sintering material to be used. Furthermore, the coating must be thermally conductive, but this is generally the case for metallic coatings.

[0026] The walls along its guiding fluid lines can be parallel to and / or perpendicular to the side of the redistribution substrate away from the MEMS mirror array structure.

[0027] If the fluid conduit extends parallel to the redistribution substrate, it can be directly adjacent to the redistribution substrate—assuming the redistribution substrate forms part of the cavity wall. In this case, the heat conduction path from the MEMS mirror array structure to the fluid conduit or the heat transfer fluid within it is advantageously shorter.

[0028] Extending fluid lines along a wall perpendicular to the redistribution substrate may be advantageous for the production of MEMS mirror array modules—especially if the wall in question is not part of the redistribution substrate: the fluid lines can then be arranged on the wall, for example through an opening in the cavity that is later hidden by the redistribution substrate in the final state, and can optionally be fixed there by integral bonding, followed by sealing only the cavity.

[0029] In principle, the cavity according to the invention can be formed from components known in the prior art, particularly from a redistribution substrate and / or interface elements. However, it has been found advantageous and preferred that the cavity and its walls be formed at least partially by spacer elements disposed between the redistribution substrate and the interface elements. If the spacer element forms a portion of the cavity wall along which a fluid conduit is guided, the spacer element should be configured to be thermally conductive at least in this region to ensure a thermally conductive connection with the redistribution substrate. The spacer element can be made of the same material as the redistribution substrate. The spacer element is preferably made of ceramic.

[0030] Preferably, the fluid lines are guided out of the MEMS mirror array module via interface elements in a direction parallel to the surface normal of the MEMS structure. In this case, the fluid lines are typically guided out of the MEMS mirror array module in the direction in which the MEMS mirror array module is inserted into the upper-level component, and this generally simplifies connections to other fluid line sections.

[0031] The fluid lines in a MEMS mirror array module can be fluid line loops. In this case, heat transfer fluid can be guided from the outside through the fluid line loop. For this purpose, the fluid line in each case includes an inlet that is guided through an interface element and an outlet for connecting to the heat transfer fluid loop.

[0032] Alternatively, the fluid conduit can be a closed heat pipe, where heat is transferred from the hotter end (typically one end located within the cavity) to the colder end, purely due to processes occurring inside the heat pipe. If it can be ensured that the temperature at the end of the heat pipe not positioned within the cavity is lower than the temperature inside the cavity, heat can ultimately be dissipated from the MEMS mirror array structure. Preferably, a capillary wick structure is provided inside the heat pipe to ensure it truly is a heat pipe. Independently, the fluid inside the heat pipe should be adapted to the temperatures expected during use of the MEMS mirror array module, but this will not pose any problem for those skilled in the art.

[0033] Preferably, the MEMS mirror array module includes at least one application-specific integrated circuit (ASIC) for measuring the temperature in the circuit region. Using such circuitry, temperature can be measured at a point defined by the location of the circuitry within the MEMS mirror array module. This information can be recorded solely for monitoring purposes. However, for active temperature control purposes, the information can also be used in one or more suitably designed ASICs. In this case, the temperature can be influenced, for example, by adjusting the temperature and / or flow rate of the heat transfer fluid through a fluid conduit, or by adjusting the temperature at the distal end of a fluid conduit in the form of a heat pipe as seen from the cavity. For example, the corresponding ASIC can be directly disposed within the MEMS mirror array structure or arranged within the cavity of the MEMS mirror array module. The desired configuration and design options for generating the corresponding circuitry are well known to those skilled in the art.

[0034] Fluid pipelines are preferably made of steel or copper. The final choice of material should take into account the corrosion resistance associated with the heat transfer fluid being supplied. Attached Figure Description

[0035] The invention will now be described by way of example with reference to the accompanying drawings, in which:

[0036] Figure 1 A schematic diagram of a photolithography projection exposure apparatus including a MEMS mirror array module according to the present invention is shown;

[0037] Figure 2 A schematic diagram of a first exemplary embodiment of a MEMS mirror array module according to the present invention is shown;

[0038] Figure 3 A schematic diagram of a second exemplary embodiment of a MEMS mirror array module according to the present invention is shown; and

[0039] Figure 4 A schematic diagram of a third exemplary embodiment of the MEMS mirror array module according to the present invention is shown. Detailed Implementation

[0040] Figure 1 A schematic meridional section of the photolithography projection exposure apparatus 1 is shown. In this case, the projection exposure apparatus 1 includes an illumination system 10 and a projection system 20.

[0041] The illumination system 10 illuminates the object field 11 in the object plane or mask master plane 12. For this purpose, the illumination system 10 includes an exposure radiation source 13, which, in the illustrated exemplary embodiment, emits illumination radiation containing light in the EUV range, specifically having wavelengths between 5 nm and 30 nm. The exposure radiation source 13 can be a plasma source, such as an LPP (laser-generated plasma) source or a GDPP (gas discharge-generated plasma) source. It can also be a synchrotron-based radiation source. The exposure radiation source 13 can also be a free-electron laser (FEL).

[0042] The illumination radiation emitted from the exposure radiation source 13 is initially focused into the concentrator 14. The concentrator 14 may be a concentrator having one or more elliptical and / or hyperboloidal reflective surfaces. The illumination radiation may be incident on at least one reflective surface of the concentrator 14 at grazing incidence (GI) (i.e., at an angle of incidence greater than 45°) or normal incidence (NI) (i.e., at an angle of incidence less than 45°). The concentrator 14 may be structured and / or coated, on the one hand to optimize its reflectivity to the radiation used, and on the other hand to suppress intrusive light.

[0043] Downstream of the light collector 14, the illumination radiation propagates through the intermediate focal point in the intermediate focal plane 15. If the illumination system 10 is constructed with a modular design, the intermediate focal plane 15 can, in principle, be used to separate (including structurally) the illumination system 10 into a radiation source module (which includes the exposure radiation source 13 and the light collector 14), and an illumination optical unit 16 as described below. In the case of such separation, the radiation source module and the illumination optical unit 16 together form the modularly constructed illumination system 10.

[0044] The illumination optics unit 16 includes a deflector 17. The deflector 17 may be a planar deflector, or alternatively a mirror with a beam-affecting effect beyond a pure deflection effect. Alternatively or additionally, the deflector 17 may be implemented as a spectral filter that separates the wavelength of the illumination radiation used from the intrusive light having a wavelength that deviates from it.

[0045] Deflector 17 is used to deflect radiation emitted from exposure radiation source 13 to first faceted mirror 18. If—as in the present case—the first faceted mirror 18 is arranged in a plane of illumination optics unit 16, which serves as a field plane optically conjugate with mask master plane 12, then this faceted mirror is also called a field faceted mirror.

[0046] The first faceted reflector 18 comprises a plurality of micromirrors 18', each of which can be individually pivoted about two mutually perpendicular axes for the purpose of controllable terrain faceting. Each facet is preferably designed with an orientation sensor (not shown) for determining the orientation of the micromirror 18'. Thus, the first faceted reflector 18 is a microelectromechanical system (MEMS system), as described, for example, in DE 10 2008 009 600 A1.

[0047] The second faceted mirror 19 is arranged downstream of the first faceted mirror 18 in the beam path of the illumination optics unit 16, resulting in a double-faceted system, the basic principle of which is also known as a fly-eye integrator. If the second faceted mirror 19 (as in the illustrated exemplary embodiment) is arranged in the pupil plane of the illumination optics unit 16, it is also called a pupil faceted mirror. However, the second faceted mirror 19 may also be arranged at a distance from the pupil plane of the illumination optics unit 16, thus the specular reflector is produced by a combination of the first and second faceted mirrors 18, 19, as described, for example, in US 2006 / 0132747 A1, EP1 614 008 B1, and US 6,573,978.

[0048] The second faceted reflector 19 does not, in principle, need to be composed of pivotable micromirrors. Instead, it may comprise individual facets formed by a single reflector or a manageable number of reflectors, which are significantly larger than the micromirrors. These facets are either stationary or can only be tilted between two defined end positions. However, as shown, the second faceted reflector 19 may also be provided as a microelectromechanical system with multiple micromirrors 19', each of which can individually pivot about two mutually perpendicular axes. Each micromirror 19' preferably includes an orientation sensor.

[0049] The individual facets of the first faceted mirror 18 are imaged into the object field 11 by means of the second faceted mirror 19, which is typically only an approximate image. The second faceted mirror 19 may be the final beam-shaping mirror, or in fact the final mirror reflecting the illumination radiation in the beam path upstream of the object field 11.

[0050] In each case, one facet of the second faceted mirror 19 is precisely assigned to one facet of the first faceted mirror 18 to form an illumination channel for illuminating the object field 11. This can in particular result in illumination according to Köhler's principle.

[0051] For the purpose of illuminating the object field 11, the facets of the first faceted mirror 18 are superimposed on each other through the corresponding facets of the second faceted mirror 19 to form an image. Here, the illumination of the object field 11 is as uniform as possible. It preferably has a uniformity error of less than 2%. Field uniformity can be achieved by superimposing different illumination channels.

[0052] By selecting the final illumination channel (which can be achieved without problems through the proper setting of the micromirrors 18' of the first faceted mirror 18), the intensity distribution in the entrance pupil of the projection system 20, as described below, can still be set. This intensity distribution is also referred to as the illumination setting. Incidentally, it may be advantageous here to arrange the second faceted mirror 19 imprecisely in a plane optically conjugate with the pupil plane of the projection system 20. In particular, the pupil faceted mirror 19 may be arranged tilted relative to the pupil plane of the projection system 20, for example, as described in DE 10 2017 220 586 A1.

[0053] However, in such Figure 1 In the arrangement of components of the illumination optical unit 16 shown, the second faceted mirror 19 is arranged in a region conjugate with the entrance pupil of the projection system 20. The deflecting mirror 17 and the two faceted mirrors 18, 19 are arranged to be tilted relative to the object plane 12 and relative to each other in each case.

[0054] In an alternative embodiment (not shown) of the illumination optics unit 16, a transmission optics unit comprising one or more mirrors may be additionally provided in the beam path between the second faceted mirror 19 and the object field 11. The transmission optics unit may specifically include one or two normal incident mirrors (NI mirrors) and / or one or two grazing incident mirrors (GI mirrors). Using the additional transmission optics unit, different orientations of the incident pupils for the tangential and sagittal beam paths of the projection system 20 described below can be particularly considered.

[0055] Alternatively, it can be omitted Figure 1 The deflector 17 shown is used for this purpose. For this purpose, the faceted mirrors 18 and 19 should be properly arranged relative to the radiation source 13 and the light collector 14.

[0056] The object field 11 in the mask master plane 12 is transferred to the image field 21 in the image plane 22 by means of the projection system 20.

[0057] For this purpose, the projection system 20 includes a plurality of reflectors Mi, which are sequentially numbered according to their arrangement in the beam path of the projection exposure device 1.

[0058] exist Figure 1 In the example depicted, the projection system 20 includes six reflectors M1 to M6. It can also have four, eight, ten, twelve, or any other number of reflectors M1. iAlternatives are also possible. The penultimate reflector M5 and the last reflector M6 each have a channel opening for illumination radiation, thus the projection system 20 shown is a double-shielded optical unit. The projection system 20 has an image-side numerical aperture greater than 0.3, or it can be greater than 0.6, for example, it can be 0.7 or 0.75.

[0059] The reflecting surface of mirror Mi can be a free-form surface without a rotational axis of symmetry. However, mirror M... i The reflective surface can also be alternatively designed as an aspherical surface with exactly one axis of rotational symmetry of its shape. Like the reflector in illumination optics unit 16, reflector M... i It can have a highly reflective coating for illumination radiation. These reflective coatings can be designed as multilayer coatings, especially with alternating layers of molybdenum and silicon.

[0060] The projection system 20 has a large object-image offset in the y-direction between the y-coordinate of the center of the object field 11 and the y-coordinate of the center of the image field 21. This object-image offset in the y-direction can have a magnitude approximately the same as the z-distance between the object plane 12 and the image plane 22.

[0061] In particular, the projection system 20 can be designed to be deformable, that is, it has different imaging scales β, especially in the x and y directions. x β y The two imaging scales β of the projection system 20 x β y Preferably (β) x ,β y = (+ / -0.25, / +-0.125). An imaging scale β of 0.25 here corresponds to a reduction in ratio of 4:1, while an imaging scale β of 0.125 results in a reduction in ratio of 8:1. A positive sign in the case of imaging scale β means imaging without image inversion; a negative sign indicates imaging with image inversion.

[0062] Other imaging scales are also possible. An imaging scale β with the same sign and the same absolute size in both the x and y directions. x β y That's also possible.

[0063] The number of intermediate image planes in the x and y directions of the beam path between object field 11 and image field 21 may be the same or different, depending on the embodiment of projection system 20. Examples of projection systems 20 with different numbers of such intermediate images in the x and y directions are known from US 2018 / 0074303 A1.

[0064] Specifically, the projection system 20 may include concentric entrance pupils. These can be accessible, or they may be inaccessible.

[0065] A mask master 30 (also referred to as a mask), arranged in the object field 11, is exposed by the illumination system 10 and transferred onto the image plane 21 by the projection system 20. The mask master 30 is held by a mask master holder 31. The mask master holder 31 can be displaced in the scanning direction, in particular, by a mask master displacement driver 32. In the exemplary embodiment shown, the scanning direction extends in the y-direction.

[0066] The structure on the mask master 30 is imaged onto the photosensitive layer of the wafer 35, which is arranged in the image field 21 region of the image plane 22. The wafer 35 is held by a wafer holder 36. The wafer holder 36 can be moved in the y-direction, in particular, by a wafer displacement driver 37. The displacement of the mask master 30, first by the mask master displacement driver 32, and the displacement of the wafer 35, secondly by the wafer displacement driver 37, can be synchronized with each other.

[0067] Figure 1 The projection exposure device 1 or its illumination system 10 shown (the above description of which substantially reflects known prior art) is characterized in that the first and / or second faceted reflectors 18, 19 are each composed of a plurality of MEMS reflector array modules 100 according to the invention (see [link to documentation]). Figures 2 to 4 Each MEMS mirror array module 100 contains multiple micromirrors 18' and 19'. Individual MEMS mirror array modules 100 are fixed to higher-level components to form a unified structure. Figure 1 The faceted reflectors 18 and 19 are schematically depicted. In addition to mechanical fixation, the upper-level assembly provides any necessary connections to the individual reflector array module 100, such as to control electronics and / or cooling circuits.

[0068] Figure 2 A first exemplary embodiment of a MEMS mirror array module 100 according to the present invention is schematically illustrated. The illustration here is in the form of two cross-sectional views, the intersecting lines of which are identified in the corresponding other view. For clarity, the shading lines of the cut bodies have been omitted.

[0069] The MEMS mirror array module 100 initially includes an actual MEMS mirror array structure 110, which includes actual micromirrors 18', 19' and the mechanical means and actuators required for their controllable pivoting. Sensors for determining the angular position of the individual micromirrors 18', 19' may also be provided. The actual MEMS mirror array structure 110 is known from the prior art and is described, for example, in DE 10 2015 204 874 A1, DE 10 2015 220 018 A1 and DE 10 2008 009 600 A1. Therefore, a detailed description of the MEMS mirror array structure 110 can be omitted in the present context.

[0070] The MEMS mirror array structure 110 is fixed to a thermally conductive redistribution substrate 120 made of silicon. Here, the MEMS mirror array structure 110 is connected or bonded to the redistribution substrate 120 not only thermally but also selectively electrically, so as to convert the electrical contacts of the MEMS mirror array structure 110 used for operation into electrical contacts that can connect, for example, electrical control and power supply lines 121. Furthermore, the redistribution substrate 120 provides structural integrity for the MEMS mirror array structure 110, which itself may not possess sufficient structural integrity.

[0071] Spacer element 130 is thermally connected to redistribution substrate 120. This spacer element is also made of silicon or ceramic and is therefore thermally conductive. On the side of spacer element 130 facing away from redistribution substrate 120, the spacer element is connected to interface element 140.

[0072] The spacer element 130 together with the redistribution substrate 120 forms a cavity 150, the walls 151 of which are partially formed by the redistribution substrate 120 and partially by the spacer element 130. Since a portion of the wall is formed by the redistribution substrate 120 itself, while the remainder of the wall is formed by the spacer element 130 which is thermally connected thereto, all the walls 151 of the cavity can be considered to be thermally connected to the redistribution substrate 120.

[0073] Interface element 140 is designed to secure the MEMS mirror array module 100 to a higher-level assembly. In the illustrated exemplary embodiment, interface element 140 is conical, allowing it to be inserted into a suitable opening in the carrier plate. It extends parallel to the surface normal of the MEMS mirror array structure 110, indicated by arrow 90. Electrical control and power lines 121 are guided to the outside through the top surface 141 of interface element 140, such that the control and power lines 121, after being pre-inserted into the suitable opening in the carrier plate, generally do not obstruct the subsequent insertion of the MEMS mirror array module 100 therein.

[0074] The MEMS mirror array module 100 also includes a fluid pipeline 200. The fluid pipeline 200 is in the form of a fluid pipeline loop, with its inlet 201 and outlet 202 leading out of the MEMS mirror array module 100 via an interface element 140 in a manner parallel to the surface normal 90 of the MEMS mirror array structure 110. This allows them to be interpreted in the context of the electrical control and power supply lines 121 when the MEMS mirror array module 100 is inserted into an opening provided for it in a higher-level component.

[0075] Fluid line 200 extends into cavity 150 and is guided there in a thermally conductive contact in a loop along the wall 151 of cavity 150—more precisely, a portion of wall 151 formed by redistribution substrate 120. In this case, fluid line 200 is integrally joined to the aforementioned portion of wall 151 by brazing. Therefore, the material 152 used for integral joining is thermally conductive solder.

[0076] In order to enable the fluid lines 200 to be soldered to the silicon-based wall 151 or redistribution substrate 120, the area of ​​the wall 151 in question is provided with a metal coating 153. The materials of the metal coating 153, the integral bonding 152 (i.e., solder), and the fluid lines 200 are matched to each other to ensure a reliable and robust connection throughout the expected temperature range during the intended use of the MEMS mirror array module 100.

[0077] If the fluid line 200 or its inlet and outlet 201, 202 are properly connected to the heat transfer fluid loop, particularly the cooling loop, proper temperature control of the heat transfer fluid results in a temperature difference between the MEMS mirror array structure 110 and the heat transfer fluid in the region of the fluid line 200. The MEMS mirror array structure 110 may have an undesirably elevated temperature due to inherent heat and absorbed radiation, and the heat transfer fluid is guided along the wall 151 in thermally conductive contact through the region of the fluid line 200. Since the entire path between the MEMS mirror array structure 110 and the heat transfer fluid in the fluid line 200 is configured to be thermally conductive, heat can be dissipated from the MEMS mirror array structure 110, thereby reducing the temperature in the MEMS mirror array structure 110. In principle, reversing the temperature difference would also allow the MEMS mirror array structure 110 to be heated, but this is practically ineffective in practice.

[0078] The temperature of the MEMS mirror array structure 110 can be actively controlled. To this end, the MEMS mirror array structure 110 may include one or more application-specific integrated circuits (ASICs), each of which measures the temperature of the MEMS mirror array structure 110. The measured temperature value can then be transmitted to a higher-level controller via electrical control and power supply line 121, which then controls the flow rate and / or temperature of the heat transfer fluid guided through the fluid line 200.

[0079] Figure 3 A second exemplary embodiment of the MEMS mirror array module 100 according to the present invention is schematically illustrated. In the illustrations and construction, Figure 3 The MEMS mirror array module 100 is largely similar to Figure 2 The MEMS mirror array module. Therefore, referring to the above statements, and only discussing the differences between the two exemplary embodiments below.

[0080] According to Figure 3 In an exemplary embodiment, a loop-guided fluid line 200 is guided in thermal contact along a portion of the wall 151 of the cavity 150, in which the wall 151 extends perpendicular to the underside of the redistribution substrate 120.

[0081] Furthermore, the integral joint between the fluid line 200 and the portion of the wall 151 is achieved by silver sintering, resulting in the material used for the integral joint 152 being sintered silver and thermally conductive.

[0082] For the envisioned integral joint, a metallic and therefore thermally conductive coating 153 is applied to the area of ​​the wall 151, along which the fluid line 200 is guided in a thermally conductive contact, since the spacer element 130 of this portion of the wall 151 forming the cavity 150 is made of silicon or ceramic.

[0083] Figure 4 A third exemplary embodiment of the MEMS mirror array module 100 according to the present invention is schematically illustrated. In the illustrations and construction, Figure 4 The MEMS mirror array module 100 is largely similar to Figure 2 The MEMS mirror array module. Therefore, reference to... Figure 2 The relevant statements are as follows, and the differences between the two exemplary embodiments are discussed below.

[0084] according to Figure 4 Fluid pipeline 200 with Figure 2The fluid line 200 is guided in a similar manner along the underside of the redistribution substrate 120, which is part of the wall 151 of the cavity 150. However, the fluid line 200 is not a fluid line loop, but a closed heat pipe because it has a capillary wick structure inside. One end of the fluid line 200 is disposed in the cavity 150, while the other end protrudes from the interface element 140. In the mounted state of the MEMS mirror array module 100, the end of the fluid line 200 extending from the interface element 140 can be thermally connected to a heat sink so that heat from the MEMS mirror array structure 110 can be dissipated in this way.

[0085] The fluid line 200 is secured to the cavity wall 151 by an adhesive, which forms an integral joint 152. The adhesive is thermally conductive and, in particular for this purpose, includes silver particles. In this case, the metal coating 153 can be omitted (see [link to documentation]). Figure 2 and Figure 3 ).

Claims

1. A MEMS mirror array module (100) includes a MEMS mirror array structure (110) disposed on a redistribution substrate (120) and an interface element (140) disposed on the side of the redistribution substrate (120) opposite to the MEMS mirror array structure (110) and used to fix the MEMS mirror array module (100) to a higher-level component. Its features are, A cavity (150) is provided between the redistribution substrate (120) and the interface element (140), and the wall (151) of the cavity is at least thermally connected to the redistribution substrate (120), and a fluid line (200) for conducting heat transfer fluid is guided along the wall (151) in a thermally conductive contact, at least one end of the fluid line being guided out of the MEMS mirror array module (100) through the interface element (140).

2. The MEMS mirror array module according to claim 1, Its features are, The fluid line (200) is integrally joined to the wall (151), and the material used for the integral joint (152) is thermally conductive.

3. The MEMS mirror array module according to claim 2, Its features are, The material used for the integral joint (152) is solder, preferably a high melting point solder for brazing at temperatures above 450°C.

4. The MEMS mirror array module according to claim 2, Its features are, Preferably, a thermally conductive adhesive comprising silver particles and / or hexagonal boron nitride particles is used as the material for integral bonding (152).

5. The MEMS mirror array module according to claim 2, Its features are, The integral bonding is achieved by sintering, preferably silver sintering.

6. The MEMS mirror array module according to any one of the preceding claims, Its features are, A metallic coating (153) is applied to at least a portion of the wall (151) along which the fluid line (200) is guided.

7. The MEMS mirror array module according to any one of the preceding claims, Its features are, The wall (151) along which the fluid conduit (200) is directed is parallel to and / or perpendicular to the side of the redistribution substrate (120) away from the MEMS mirror array structure (110).

8. The MEMS mirror array module according to any one of the preceding claims, Its features are, The cavity (150) and its wall (151) are formed at least in part by a spacer element (130) disposed between the redistribution substrate (120) and the interface element (140), wherein the spacer element (130) is preferably made of ceramic.

9. The MEMS mirror array module according to any one of the preceding claims, Its features are, The fluid pipeline (200) is guided out of the MEMS mirror array module (100) through the interface element (140) in a direction parallel to the surface normal (90) of the MEMS mirror array structure (110).

10. The MEMS mirror array module according to any one of the preceding claims, Its features are, The fluid line (200) is a fluid line loop having an inlet (201) that is guided through the interface element (140) and an outlet (202) for connection to the heat transfer fluid loop.

11. The MEMS mirror array module according to any one of the preceding claims, Its features are, The fluid line (200) is a closed heat pipe, which preferably has a capillary structure inside.

12. The MEMS mirror array module according to any one of the preceding claims, Its features are, The MEMS mirror array structure (110) includes one or more application-specific integrated circuits (ASICs), and / or one or more ASICs are disposed in the cavity (150), wherein at least one ASIC is configured to measure the temperature in the region of the circuit.

13. The MEMS mirror array module according to any one of the preceding claims, Its features are, The fluid pipeline (200) is made of steel or copper.

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