Assembly with cooling structure arrangement, method for manufacturing the assembly

Abstract

The invention relates to an assembly 1 with a component arrangement 2, wherein the component arrangement 2 has at least one component 3, with a cooling structure arrangement 8, wherein the cooling structure arrangement 8 is applied in a primary manner to a cooling side 15 of the component arrangement 2, with a cover arrangement 10, wherein the cover arrangement 10 seals the cooling structure arrangement 8 so that a fluid space 11 is formed through which a cooling fluid can flow, wherein the component arrangement 2 has a dry side 16, wherein the at least one component 3 is arranged on the dry side 16.

Description

Prior ArtThe invention relates to an assembly with a cooling structure arrangement having the features of the preamble of claim 1.Coolers based on the current state of the art for power electronics are usually based on dedicated components manufactured independently of the unit to be cooled. These coolers have connecting surfaces, on which the unit to be cooled is in turn joined. Typical joining methods are, for example, adhesive bonding, soldering or sintering. The joining methods have different advantages and disadvantages with regard to costs and performance.The publication DE 10 2021 209 482 A1 discloses an electronic module having at least one power semiconductor which is electrically connected to a contacting arrangement, and having at least one cooling element for at least indirectly cooling the at least one power semiconductor, wherein the at least one cooling element is designed as a cooling element produced in an additive manufacturing method, and in that the at least one cooling element is arranged between the at least one power semiconductor and the contacting arrangement and electrically connects the at least one power semiconductor to the contacting arrangement. The power semiconductor is disposed in the cooling medium.Disclosure of the InventionThe subject matter of the invention is an assembly having the features of claim 1 and a method having the features of claim 14.The invention relates to an assembly which, in the most general form of the invention, is designed as any desired, in particular electrical and / or electronic, assembly.The assembly has a component arrangement, wherein the component arrangement has at least one component. The component is in particular designed as an electronic and / or electrical component. In particular, the at least one component is designed as a component that generates heat during operation. In particular, the heat is generated, for example, as waste heat by the conversion of electrical power in the component.The assembly has a cooling structure arrangement, wherein the cooling structure arrangement is applied in a forming manner on a cooling side of the component arrangement. The cooling structure arrangement is thus not placed as a finished component on the cooling side, but rather is produced from a shapeless starting material. In particular, the original application leads to a cohesive connection between the component arrangement and the cooling structure arrangement. Forming is understood in particular to mean all production methods in which a solid body is produced from a non-formed fabric in order to produce a predetermined shape of the solid body and to create the fabric composition. Moulding comprises in particular additive manufacturing.Particularly preferably, the cooling structure arrangement is formed metallic, so that the base material of the cooling structure arrangement has very good thermal conductivity as metallic base material. In particular, the thermal conductivity of the metallic base material is lambda >10 W / (m.times.K).The assembly includes a lid assembly, wherein the lid assembly seals the cooling structure assembly. The seal is designed such that a fluid space is formed, through which a cooling fluid can flow.Within the scope of the invention, it is proposed that the cooling structure arrangement has a drying side, wherein the at least one component is arranged on the drying side. The dry side of the component is arranged in particular outside the fluid space, so that the component is arranged insulated from the cooling fluid.It is an advantage of the invention that optimal heat dissipation is guaranteed for the component arrangement on the one hand by the originally applied cooling structure arrangement and on the other hand, no insulation problems with regard to the electrical insulation with respect to the cooling fluid can occur due to the arrangement of the component on the dry side. In particular, the assembly to be cooled forms a carrier for the original forming process of the cooling structure production and thus represents an integral component of the fluid space.The previously customary production methods offer the possibility of taking into account the usual expected behaviour of the final joined assemblies (cooler and unit to be cooled), but have two central weaknesses: all previously customary turbulators enable only a very limited geometry which enables turbulence in all 3 spatial dimensions. The primary orientation of the turbulence is limited to 2 dimensions. They always have the same geometry and are bonded to the half tools required for production. Since the cooler units are produced independently of the assemblies to be cooled, the cooler units are not individually optimally adapted to the assemblies to be cooled and to the manufacturing-related variations thereof, which also occur inherently in large production. In addition, small series can usually not be imaged cost-effectively, since a cooler unit specifically adapted to a small series cannot be implemented. In contrast, these disadvantages are also overcome with the original production of the cooling structure arrangement.In particular, some or all of the following advantages can be achieved: the cooling structure arrangement can be individually adapted to each component arrangement to be cooled. The implementation allows a free shaping of the cooling structure arrangement, so that turbulences in all three spatial dimensions can be generated in a controlled manner. The implementation is able to react to the fluctuations in the preliminary process (during the production of the cooling arrangement) and to adapt the required cooling power optimally to these fluctuations. This allows a broader specification in the preprocesses. The implementation can be used cost-effectively for both small series and for large series. The cooling performance significantly exceeds the current state of the art. First direct comparisons show a performance improvement of >20%. The costs are significantly lower compared to separately manufactured components. Both the effective cost for the cooler structure arrangement itself, as well as the cost for the pre-processes and the resulting error costs of the overall final assembly.In a preferred embodiment of the invention, the cooling structure arrangement is applied by an additive 3D printing method and / or by selective laser sintering and / or SLM. In particular, a powder, in particular a metal powder, can be used as the starting material.In a preferred implementation of the invention, the component arrangement is designed to form a spatially resolved heat power distribution during operation, in particular during normal operation and / or control operation. In particular, a two-dimensional distribution of heat sources of the component arrangement is formed. In contrast, during operation, the cooling fluid forms a cooling power distribution in the fluid space, wherein the cooling power distribution is matched to the heat power distribution.In the case of the tuning, it can be provided that in a region of the component arrangement, wherein the at least one component is arranged in the region, an increase in the cooling power distribution, in particular a local maximum, is. In contrast, in a region of the component arrangement, wherein the region of the component is formed freely, a lowering, in particular a local minimum, can be assigned to the cooling power distribution.The cooling structure arrangement preferably has a plurality of individual structures. In particular, the surface density of the individual structures is greater in a region of the at least one component than in a component-free and / or other region. For example, the individual structures are designed as pins and / or columns. The individual structures preferably have a thickness variation in the height direction and / or Z direction perpendicular to the printed circuit board. In particular, the individual structures are designed conically, in particular in such a way that the surface density decreases in the Z direction starting from the printed circuit board.The cooling structure arrangement preferably has a height distribution. In the case of the coordination, it can be provided that a greater height of the cooling structure arrangement, in particular a local maximum, is provided in a region of the component arrangement, wherein the at least one component is arranged in the region. In contrast, in a region of the component arrangement, wherein the region of the component is formed freely, a lowering, in particular a local minimum, can be assigned to the cooling structure arrangement.Particularly preferably, the cooling structure arrangement has a component-resolved variation of the cooling structures. In particular, the cooling structure arrangement has partial surfaces spaced apart from one another, wherein each of the partial surfaces is individually and / or selectively assigned to a component. The cooling structure arrangement is thus applied only where it is required for the heat removal.In a preferred development of the invention, the cooling structure arrangement has a density distribution, wherein the density of the cooling structure arrangement varies along the height and / or in a surface extension parallel to the cooling side. The different density can be converted into the material produced by the original production, for example by adapting a porosity in the cooling structure arrangement. Thus, the cooling power individually adapted to the process variations or component distribution can be achieved in particular by adjusting the density of the primary-formed cooling structures with respect to the surface to be cooled. In particular, the varying density distribution makes possible a local adaptation of the cooling power, for example with a constant height and thus without changing any connection geometries of the cooling structure arrangement.In a preferred embodiment of the invention, the cover arrangement has. The flow guiding regions project into the fluid chamber. The flow structure in the fluid space is thus determined by a interaction between the cooling structure arrangement and the flow guiding regions of the cover arrangement. In particular, the flow guidance regions in the cover arrangement are irregularly distributed. It is thus possible not only to control the flow in the fluid space by the cooling structure arrangement, but additionally by flow guide regions of the cover arrangement. In particular, a function distribution takes place, wherein the heat removal is implemented, in particular by the component-resolved variation of the cooling structures, and the flow line of the cooling fluid through the flow guide regions of the cover arrangement. In this way, the circumference of the cooling structure arrangement can be limited to a minimum and manufacturing costs can be saved.In a particularly simple embodiment of the invention, the cover arrangement is arranged sealingly on the component arrangement. Thus, the cover arrangement forms one sealing partner and the component arrangement forms the other sealing partner. Optionally, the cover arrangement has interfaces for coupling to a cooling circuit. In particular, the interfaces comprise a fluid inlet and a fluid outlet.In a preferred implementation of the invention, the component arrangement has a printed circuit board, wherein the at least one component is applied to the printed circuit board. In particular, a conductive coating or printing is applied on the dry side of the circuit board for contacting the at least one component.The circuit board preferably has a ceramic core, wherein the ceramic core provides particularly good thermal conductivity, such that the thermal path between the at least one component via the circuit board to the cooling structure arrangement and thus into the fluid chamber assumes the smallest possible thermal conductivity value. For example, the circuit board is designed as an AMB circuit board. 13.In a preferred implementation of the invention, the component is designed as a high-power switching element, for example MOSFET or IGBT. The module is preferably designed as an inverter and / or voltage converter module for an electric drive of an electric and / or hybrid vehicle.The invention further relates to a method for producing an assembly, in particular the assembly as described above. In this case, the component arrangement is measured, in particular characterized electrically, in order to determine the heat power distribution during operation. This can be done by direct measurement of the thermal power distribution, for example with a thermal imaging camera; alternatively, this can be done indirectly by measuring the components and estimating the thermal power distribution. On the basis of the heat output distribution, a cooling structure arrangement and optionally additionally a cover arrangement with flow guiding regions with a matching cold output distribution is modeled and subsequently applied or manufactured in a forming manner to the component arrangement. Optionally, the cooling structure arrangement and optionally additionally the cover arrangement is adapted to a type of component arrangement, so that all component arrangements of this type receive the same cooling structure arrangement and optionally additionally the same cover arrangement. Alternatively, each component arrangement is individually adapted, so that each component arrangement receives an individually modeled cooling structure arrangement and optionally additionally an individually modeled cover arrangement.In particular, the cooling structure arrangement is determined such that a predeterminable or simulated 3D turbulence or 3D turbulence configured by way of optimization method is implemented during operation of the assembly.Spatially resolved adaptable structuring for performance-optimized cooling: The original application, in particular the 3D pressure, takes place only after the electrical characterization of the component to be cooled or of the component arrangement to be cooled. This makes it possible to adapt the required cooling power in a positionally accurate manner (e.g. in a chip-resolved manner) and thus to optimize the ratio of costs and performance to the maximum. In addition, this procedure enables a greater capture range or broader specification limits in the preliminary process, since fluctuations in the preliminary process can be better compensated by optimized cooling structures. This enables reduced error costs in the entire process chain. Fluctuations in the processing of the power semiconductors to be cooled can lie, for example, in the range of up to + / - 30% with respect to the so-called Rdson (conduction resistance in the "on" state of the semiconductor). Conventional "part-to-part" variation within a power module in which a plurality of such power semiconductors are installed are therefore in the range of + / -5%. This Rdson is a measure of the energy dissipation and thus the necessary local cooling power during operation. Comparable fluctuations also exist for the other parameters of the power semiconductors. The cooling system outlined here is capable of compensating for these production-based fluctuations of the preprocesses on the basis of cooler geometries locally adapted to the previously carried out module characterization. Conventional cooler systems, which are produced in advance independently of the individual module characterization, are not capable of this. For this purpose, for example, the geometry of the individual cooling structure (of the unit cell; e.g. of the pin) can be adapted, or the local density of the pins (distance between the turbulence structures such as, e.g. pins) can be varied. The pressure drop can thus be locally adapted. The pressure drop in the cooling system is likewise a central variable in order to adapt the cooling capacity. Tuning the effective cross section for the flow of the cooling medium is possible with the method.Further features, effects and advantages of the invention will become apparent from the following description of a preferred exemplary embodiment of the invention and from the attached figures. These show: FIG. 1 shows a schematic sectional view through an assembly as an exemplary embodiment of the invention; FIG. 2 shows a schematic, three-dimensional representation of a or the assembly as an exemplary embodiment of the invention, FIGS. 3 a, b, c show a schematic bottom view, sectional view and top view of an assembly as a further exemplary embodiment of the invention.Components corresponding or identical to one another are provided with mutually corresponding or identical reference numerals.FIG. 1 shows a schematic cross-sectional illustration of an assembly 1 as an exemplary embodiment of the invention. The assembly 1 is designed as an electrical and / or electronic assembly 1. In particular, the assembly 1 is designed as an inverter assembly and / or as a voltage converter assembly of power electronics for an electric drive of a vehicle. In this embodiment, it is known that waste heat is generated during operation, which has to be actively dissipated via a cooling fluid.The assembly 1 has a component arrangement 2 with at least one component 3 and a circuit board 4, wherein the at least one component 3 is arranged on the circuit board 4. The component 3 is in particular designed as a high-power switching element, such as a MOSFET, IGBT or the like, for rapid switching.The circuit board 4 is designed as a ceramic circuit board which has a ceramic core 5, wherein an electrically conductive contact layer 6, for example made of copper, is applied to the side of the circuit board 4 facing the component 3. On the opposite side, a metallic coating, printing or the like can be formed as a connecting layer 7, which can likewise be made of copper. The assembly 1 has a cooling structure arrangement 8, wherein the cooling structure arrangement 8 has a plurality of individual structures 9. The cooling structure arrangement 8 is applied in a forming manner to the component arrangement 2 and in particular to the connecting layer 7. For example, it can be applied by an additive 3D printing method or by selective laser sintering or by selective laser melting (SLM). The cooling structure arrangement 8 and / or the cooling structures 9 is / are manufactured from a metallic starting material, so that it has / have a high thermal conductivity.The assembly 1 has a cover arrangement 10, wherein the cover arrangement 10 seals the cooling structure arrangement 8 such that a fluid space 11 is formed, wherein the cooling structure arrangement 8 and / or the cooling structures 9 are arranged in the fluid space 11. For example, the cover arrangement 10 is arranged via a seal 12 in a sealing manner on the component arrangement 2 and in particular on the circuit board 4. The cover arrangement 10 can have interfaces in the form of a fluid inlet 13 and a fluid outlet 14, so that a cooling fluid can flow through the fluid chamber 11.As can be seen from FIG. 1, the fluid chamber 11 and thus the cooling fluid are arranged only on one cooling side 15 (in particular wet side) of the component arrangement 2 and in particular of the printed circuit board 4. The other side of the component arrangement 2 and in particular of the circuit board 4 is designed as a dry side 16 which is insulated from the cooling fluid and / or is arranged in an in particular dry ambient atmosphere. In particular, the at least one component 3 is arranged on the dry side 16 of the component arrangement 2 and / or of the circuit board 4.Because the cooling structure arrangement 8 is applied in a primary forming manner, it can be structured as desired. This is structured in a component-resolved manner, so that regions of the component arrangement 2 with components 3 which operate as heat sources are cooled to a greater extent than regions of the component arrangement 2 on which no components are arranged. In particular, the cooling power distribution of the cooling structure arrangement 8 is adapted to the heat power distribution of the component arrangement 2. For example, an area density of the structural elements 9 is higher in the region of a component 3 than in a region without a component. The shape, in particular the height of the cooling structures 9, can also be individually adapted to the distribution of the components 3.FIG. 2 shows a schematic, three-dimensional representation of an assembly 1, wherein the cover arrangement 10 is removed. In the cover arrangement 10, the fluid inlet 13 of the fluid outlet 14 are formed as through openings. Between the fluid inlet 13 and the fluid outlet 14 there are flow guide regions 17 which in this exemplary embodiment are designed as simple, rectilinear webs. In alternative embodiments, these may be realized in a more complex and irregular manner. The flow guiding regions 17 serve to control the fluid flow of the cooling fluid in the fluid space 11 and to guide it in a manner appropriate for use.As can be seen from the plan view of the cooling side 14 of the component arrangement 2, the individual structures 9 are arranged in partial surfaces 18 a, b, c, d, e, f, gin each case such that they each correspond to a component 3 which is arranged on the dry side.It is possible here for the structural elements 9 to be designed as simple pins or columns, so that they can control turbulence in a plane parallel to the printed circuit board 4 by distributing 2D turbulence. Alternatively, it is possible for these to have a thickness variation in the height direction and / or Z direction perpendicular to the circuit board 4 as pins or columns. Then, variations in the X-Y plane can be realized and a variable density in the Z direction can be achieved by the distribution. In particular, it is possible to control 3D turbulences. This corresponds to a "complexity-for-free" since the shape and the distribution of the structural elements 9 can be set arbitrarily during the original application within the scope of a production-oriented implementation.The cooling capacity of the cooling structure arrangement 8 is determined, among other things, significantly by the design of the so-called turbulence geometry. Whereas laminar flow of the coolant in the cooler leads to poor cooling performance, the cooling performance can be significantly influenced by suitable turbulences. Turbulences occur in all 3 spatial dimensions and are caused by the geometry of the cooling structure arrangement 8 in the respective dimension. The use of metallic 3D printing allows additional degrees of freedom in geometry without influence on the production costs (known under the keyword "Complexity-For-Free") compared to the usual production methods of standard cooling systems. Whereas the usual production methods permit undercuts in the Z axis only with great demands, it is thus possible to produce them at 3D printing without additional costs or process times. This consequently enables a cooler geometry which has an optimized turbulence in all 3 dimensions. The steepest thermal gradient in the Z axis is inherently to be expected. Due to the "Complexity-For-Free" approach in 3D printing, the cooling structure arrangement 8 thus enables the cooling path to be optimized in all 3 dimensions, including in particular the Z direction and thus along the steepest thermal gradient, which other methods can only enable at significantly increased costs.Use of the component arrangement 2 to be cooled as an integral component of the cooling circuit for optimizing costs per performance, volume and weight: A customary cooler assembly is replaced by the 3D printed cooling structure arrangement 8 which is individually optimized for the component arrangement 2 to be cooled. This pressure is applied directly to the so-called power substrate as a printed circuit board 4, so that this / this is an integral component of the cooler structure arrangement 8, which in turn reduces the thermal path to the heating source, formed as a component 3. As a result, the cooling capacity is improved inherently by 20% compared with conventional cooling systems, the volume and the weight are reduced. In total, costs per performance can thus be improved.Any (electronic) components 3 that require active cooling elements due to high power density, such as power modules for use in electric vehicles, half-bridges and full bridges in other devices (e.g. power tools), or even processors, ASICs or μCs with high power densities, can be used. For this purpose, the units to be cooled as component arrangements 2 require only one metallic interface which is suitable for the original application, in particular for the hybrid 3D printing. The original application, in particular the hybrid metallic 3D printing, is already possible on sub-μm-thick metallizations of semiconductor chips or sub-μm-thick connection layers 7. The provision of such necessary metallization is thus not a limiting factor.FIGS. 3 a, b, c show a bottom view of the cooling side 15, a sectional view and a top view of the drying side 16 of an assembly 1 as a further exemplary embodiment of the invention. In this exemplary embodiment, it can be seen that each component 3 is assigned a partial surface 18 a- hof the cooling structure arrangement 8. Due to the selective assignment, the cooling structure arrangement 8 can be designed to be very small, so that manufacturing costs can be saved.This forms an optimized combination between the cooling structure arrangement 8, which is in particular printed, and a cooling channel of the cover arrangement 10, in order to reduce the costs and to increase the performance. The cooling structure arrangement 10 is in this case printed directly onto the substrate, formed as a printed circuit board 4 of the power electronics, formed as the component arrangement 2, and inserted into the cooling duct through which the cooling medium flows. In principle, the production costs would be very high, because the process times during the application of the cooling structure arrangement 10 are correspondingly long. However, in practice, it is frequently the case that the major part of the cooling structure serves only for the purpose of controlling the cooling medium in such a way that the flow to the regions in which heat is generated is good. That is to say, the regions where the actual heat is produced are significantly smaller. Cooling structures are applied only where the heat is generated. Due to the hybrid construction, i.e. the original application to a substrate, the cooling paths are very small, which leads to very small heat spreads. In order to "fill up" the remaining structures (for optimizing the flow), these are integrated into the cooling channel of the cover arrangement 10. The cover arrangement 10 can consist, for example, of a plastic in which structures as flow guide regions 17 (FIG. 2 ) are also manufactured in the injection molding process.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2021 209 482 A1

[0003]

Claims

Assembly (1) with a component arrangement (2), wherein the component arrangement (2) has at least one component (3), with a cooling structure arrangement (8), wherein the cooling structure arrangement (8) is applied to a cooling side (15) of the component arrangement (2) in a forming manner, with a cover arrangement (10), wherein the cover arrangement (10) seals the cooling structure arrangement (8) so that a fluid space (11) is formed, through which a cooling fluid can flow, characterized in that the component arrangement (2) has a dry side (16), wherein the at least one component (3) is arranged on the dry side (16).Assembly (1) according to claim 1, characterised in that the cooling structure arrangement (8) is applied by an additive 3D printing method and / or selective laser sintering and / or SLM.Assembly (1) according to Claim 1 or 2, characterized in that the component arrangement (2) is designed to form a spatially resolved heat power distribution during operation, wherein the cooling fluid in the fluid space (11) forms a cooling power distribution during operation, wherein the cooling power distribution is matched to the heat power distribution.Assembly (1) according to one of the preceding claims, characterized in that an increase in the cooling power distribution is assigned in a region of the at least one component (3) and / or a decrease in the cooling power distribution is assigned in a region without a component or other region.Assembly (1) according to one of the preceding claims, characterized in that the cooling structure arrangement (8) has a plurality of individual structures (9), wherein the surface density of the individual structures (9) is preferably greater in a region of the at least one component (3) than in a component-free and / or other region.Assembly (1) according to one of the preceding claims, characterized in that the cooling structure arrangement (8) has a height distribution, wherein the height of the cooling structure arrangement is greater in a region of the at least one structural element (3) than in a region without a component.Assembly (1) according to one of the preceding claims, characterized in that the cooling structure arrangement (8) has a density distribution, wherein the density of the cooling structure arrangement varies along the height and / or in a surface extension parallel to the cooling side (15).Assembly according to one of the preceding claims, characterized in that the cooling structure arrangement (8) has partial surfaces (18a - h) spaced apart from one another, each of the partial surfaces (18a - h) being selectively assigned to a structural element (3).Assembly (1) according to one of the preceding claims, characterized in that the cover arrangement (10) has flow guide regions (17), wherein the flow guide regions (17) project into the fluid space (11) and / or project from the cover arrangement (10).Assembly (1) according to claim 9, characterised in that the flow guiding regions (17) cooperate with the cooling structure arrangement (8).Assembly (1) according to one of the preceding claims, characterized in that the cover arrangement (10) is arranged sealingly on the component arrangement (2).Assembly (1) according to one of the preceding claims, characterized in that the component arrangement (2) has a printed circuit board (4), wherein the at least one component (3) is applied to the printed circuit board (4).Assembly (1) according to one of the preceding claims, characterized in that the at least one component (3) is designed as a high-power switching element and / or the assembly is designed as an inverter assembly for an electric drive of a vehicle.Method for manufacturing an assembly (1), in particular an assembly (1) according to one of the preceding claims, characterized in that a component arrangement (2) is measured for determining a heat power distribution, a cooling structure arrangement (8) is subsequently determined on the basis of the heat power distribution and the cooling structure arrangement (8) is then applied to the component arrangement (2) in a forming manner.Method according to Claim 14, characterized in that the cooling structure arrangement (8) is determined in such a way that a predeterminable or simulated 3D turbulence or 3D turbulence formed by an optimization method is implemented during operation of the assembly (1), with the result that the component arrangement (2) forms a spatially resolved heat power distribution during operation, wherein the cooling fluid in the fluid space (11) forms a cooling power distribution during operation, wherein the cooling power distribution is matched to the heat power distribution.

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