Isolated heat dissipating substrate for electronic components

Abstract

The disclosure relates to an isolated heat dissipating substrate for electronic components. In particular, the disclosure relates to an assembly (100, 200, 300), comprising: a vapor chamber (120) comprising a top plate (113) and a bottom plate (114); wherein one or both of the top and bottom plates (113, 114) are shaped such that a cavity (116) is formed between the tightly joined top and bottom plates (113, 114); wherein the cavity (116) is filled with a working fluid; and an electrically isolating layer (112) attached to one of the two plates (113, 114) of the vapor chamber (120), the electrically isolating layer (112) providing a mounting surface for electronic components that is electrically isolated from the vapor chamber (120).

Description

[0001] ISOLATED HEAT DISSIPATING SUBSTRATE FOR ELECTRONIC COMPONENTS

[0002] TECHNICAL FIELD

[0003] The disclosure relates to the field of heat dissipation for electronic components, for example active electronic components such as power semiconductors. The disclosure relates to an assembly with a vapor chamber and an electrically isolating layer. For example, the disclosure relates to an isolated heat dissipating substrate for electronic components and specifically to the combination of an isolating substrate for a power semiconductor module and a vapor chamber.

[0004] BACKGROUND

[0005] Within an assembly of power electronic devices (power circuit, power converter), waste heat generated in chip(s) is transferred from a heat source (chip) to a coolant through several functional material layers. Normally, the primary design target for the thermal management of power semiconductor chips is to have this heat cause as small of a temperature gradient between the chip and the coolant as possible. In other words, it is desired to achieve a small thermal resistance between chip and coolant. This goal is accomplished by: Keeping the number of material layers and their thicknesses small, e.g. reducing the distance between chip and coolant in the main direction of the heat flow as much as other design constraints permit; and: Spreading heat perpendicular to the main direction of the heat flow to enlarge the cross-sectional area through which the heat propagates and enters the successive material layer. These design criteria can be conflicting. Adding thermally conductive material into the heat path to enhance heat spreading inevitably increases the vertical distance between heat source and coolant. This tradeoff should be improved.

[0006] SUMMARY

[0007] This disclosure provides a concept for improving the above-described design criteria, for example for enhancing heat spreading without significantly increasing the distance between heat source and coolant.

[0008] The foregoing and other objectives are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description and the figures.

[0009] According to this disclosure an assembly is provided that combines an electrical isolator and a vapor chamber. This assembly can be used as part of a power semiconductor module where it fulfills the functions of an isolating metallized ceramic substrate and a heat spreader as one functional unit. One of the metal layers of the isolating module substrate simultaneously serves as one plate of the vapor chamber.

[0010] Embodiments described in this disclosure are related to an assembly that serves as an isolating substrate and a heat spreader for power semiconductor devices. The assembly combines the functionalities of a metallized ceramic substrate and a vapor chamber, with a reduced part count, and having a short path between chip and heat sink. The substrate is electrically isolating between one side which is configured to encompass electrically active parts and the opposite side which is configured to dissipate heat generated by the electrically active parts during their operation towards a heat sink. The described assembly introduces a heat spreader in form of a vapor chamber into the heat path, but does not add all the layers of material that would result from adding a metallized ceramic substrate and a vapor chamber as separate subassemblies. In order to describe the disclosure in detail, the following terms and notations will be used.

[0011] DBC direct bonded copper

[0012] DBA direct bonded aluminum

[0013] AMB active metal brazing

[0014] MCB metal casting direct bonding

[0015] In this disclosure, electronic components are described. Such electronic components can be active and / or passive devices. Active devices can be power semiconductors, for example. Power semiconductor modules most prominently contain power semiconductor devices, “chips”. While the following statements mention and primarily refer to semiconductor chips, other types of circuit elements that are housed inside the module, be they in the shape of chips or another, are equally within scope. Power semiconductor modules can contain heat spreaders for more effective heat dissipation.

[0016] In this disclosure, vapor chambers are described. Vapor chambers can be used as heat spreaders for power semiconductor modules. Vapor chambers can be attached to either side of metallized ceramic substrates, both parts together forming a subassembly inside power semiconductor modules. The disclosure presents an innovative assembly combining an electrical isolator and a vapor chamber.

[0017] In this disclosure, the terms “top” and “bottom” are used to define orientations and positions. These terms refer to an assumed exemplary orientation where the substrate or module is oriented horizontally with the chips located on the upper side and the heat sink located at or towards the lower side of the substrate / module. The drawings show this orientation. The orientation in which the substrate / module is manufactured or mounted can differ from the shown orientation.

[0018] Corresponding to this assumed orientation, the directions of the heat transport are referred to as “vertically”, meaning from top to bottom, in the main direction of propagation from heat source to sink, and “laterally”, meaning sideways in horizontal direction, perpendicular to the main direction of propagation.

[0019] All descriptions treat substrates as if they had two sides, top and bottom. In fact, substrates would normally have four other faces (left, right, front, back). As substrates are flat objects, these flat faces function more like edges than like faces. To clarify, the sides meant in this disclosure are the two large-area ones facing each other.

[0020] Isolation as described in this disclosure means functional electrical isolation.

[0021] According to a first aspect, the disclosure relates to an assembly, comprising: a vapor chamber comprising a top plate and a bottom plate; wherein one or both of the top and bottom plates are shaped such that a cavity is formed between the tightly joined top and bottom plates; wherein the cavity is filled with a working fluid; and an electrically isolating layer attached to one of the two plates of the vapor chamber, the electrically isolating layer providing a mounting surface for electronic circuit elements that is electrically isolated from the vapor chamber.

[0022] Such an assembly can combines the two approaches of cooling system design as described above, e.g., keeping the number of material layers and their thicknesses small, and spreading heat perpendicular to the main direction of the heat flow, to achieve highly effective heat transfer between the electronic component, e. g. the chip, and the coolant. The presented assembly includes only the necessary functional layers, namely an electrical isolator and a heat spreader in form of a vapor chamber. As one result, this functional unit can achieve a superior tradeoff in dissipating heat. If compared to a common module design without heat spreader, the assembly, due to the vapor chamber with its exceptionally high heat transfer capability in lateral direction, helps distribute the heat over a wider area for a more effective transfer to the coolant. Compared to a metallized ceramic substrate attached to a vapor chamber, the above-described assembly comprises fewer parts, giving advantages in terms of weight, cost and thermal resistance. The assembly can also be used as a subassembly in module manufacture with a small number of process steps. Advantages that can be achieved for the end product by using the above-described assembly are reduced cost, weight and volume or increased lifetime.

[0023] In an exemplary implementation of the assembly, one or both of the plates are non-flat shaped in a lateral portion of the vapor chamber and are flat in a central portion of the vapor chamber; wherein the electrically isolating layer is attached to a flat portion of the vapor chamber. The flat shape in the central portion enables attachment of a flat shaped electrically isolating layer which can be easily attached thereon.

[0024] In an exemplary implementation of the assembly, the assembly comprises: an electrically conductive layer attached to the electrically isolating layer; wherein the electrically isolating layer is electrically isolating the electrically conductive layer from the vapor chamber. The electrically conductive layer enables attachment of electronic components thereupon which are electrically isolated from the vapor chamber.

[0025] In an exemplary implementation of the assembly, the assembly comprises: one or more electronic components attached to the electrically conductive layer. Heat generated by the electronic components can be efficiently dissipated by the vapor chamber. Due to the vapor chamber with its exceptionally high heat transfer capability in lateral direction, the heat from the electronic components can be distributed over a wider area for a more effective transfer to the coolant.

[0026] In an exemplary implementation of the assembly, the assembly comprises: a bonding layer bonding the one or more electronic components to the electrically conductive layer. The bonding layer helps attaching the electronic components to the electrically conductive layer.

[0027] In an exemplary implementation of the assembly, the electrically conductive layer comprises two or more segments separated from each other; wherein at least one electronic component is attached to at least one segment of the two or more segments. These segments separated from each other allow to attach several electronic components to the electrically conductive layer. The assembly can thus serve as a carrier for one or for a multitude of electronic components. Alternatively, or additionally, separate segments of the electrically conductive layer can be utilized to connect different electrodes of an electronic component to individual segments.

[0028] In an exemplary implementation of the assembly, the two or more segments of the electrically conductive layer are at different electric potentials. Accordinlgy, the assembly can be used to form an electronic circuit or part of an electronic circuit with different electric potentials.

[0029] In an exemplary implementation of the assembly, the two or more segments of the electrically conductive layer have different sizes. This allows placing different electronic components on the electrically conductive layer. Larger electronic components, or a higher number of components, can be placed onto a larger size segment and smaller electronic components, or a smaller number of components, can be placed onto a smaller size segment.

[0030] In an exemplary implementation of the assembly, the assembly comprises at least one electronic component. The assembly allows heat dissipation for one electronic component or for more than one electronic component. Depending on the circuit design, multiple power semiconductor devices can be placed on the electrically conductive layer. Heat generated by these one or more power semiconductor devices can be efficiently transferred by the vapor chamber.

[0031] In an exemplary implementation of the assembly, the electronic components are of one or several of the following types: power semiconductor device, processor, integrated circuit, light emitting diode, resistor, inductor or capacitor. The assembly allows designs of a variety of electrical and electronic circuits comprising electronic components of the above-described types.

[0032] In another exemplary implementation of the assembly, the assembly comprises: one or more electronic components attached to a first one of the two plates of the vapor chamber which is not attached to the electrically isolating layer; and a bonding layer bonding the one or more electronic components to the first one of the two plates of the vapor chamber. This allows attachment of electronic components directly on the vapor chamber.

[0033] In an exemplary implementation of the assembly, either or both of the electrically conductive layer and the plate of the vapor chamber, to which the electrically isolating layer is attached, are made of a metal, wherein the electrically isolating layer is made of a ceramic material, wherein at least one of the electrically conductive layer and the plate of the vapor chamber, to which the electrically isolating layer is attached, is interconnected with the electrically isolating layer through a bond between ceramic and metal which is fabricated by means of one of the following technologies: direct bonded copper, DBC, direct bonded aluminum, DBA, active metal brazing, AMB, metal casting direct bonding, MCB. These are established manufacturing technologies that create a tight and reliable bond between ceramic and metal layers.

[0034] In an exemplary implementation of the assembly, the cavity of the vapor chamber comprises a support structure that is configured to support the top plate and the bottom plate of the vapor chamber against deformation. Such a support structure improves robustness of the vapor chamber and the whole assembly.

[0035] In an exemplary implementation of the assembly, the vapor chamber is configured to dissipate heat generated by the electronic components in lateral direction. Dissipating heat in lateral direction is very effective. By dissipating heat in lateral direction, the vapor chamber is highly suited to distribute heat and levelling out temperature gradients.

[0036] According to a second aspect, the disclosure relates to a method for producing an assembly, the method comprising: providing a vapor chamber comprising a top plate and a bottom plate; wherein one or both of the top and bottom plates are shaped such that a cavity is formed between the tightly joined top and bottom plates; wherein the cavity is filled with a working fluid; and attaching an electrically isolating layer to one of the two plates of the vapor chamber, wherein the electrically isolating layer provides a mounting surface that is electrically isolated from the vapor chamber.

[0037] Such a method allows producing an assembly that advantageously combines the two approaches of cooling system design to achieve highly effective heat transfer between the electronic component, e. g. the chip, and the coolant. The produced assembly includes only the necessary functional layers, namely an electrical isolator and a heat spreader in form of a vapor chamber. The method enables production of an assembly achieving a superior tradeoff in dissipating heat.

[0038] BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Further embodiments of the disclosure will be described with respect to the following figures, in which: Figure 1 shows a schematic diagram illustrating an assembly 100 according to a first embodiment with a continuous top conductor layer 111;

[0040] Figure 2 shows a schematic diagram illustrating an assembly 200 according to the first embodiment with a patterned top conductor layer 111;

[0041] Figure 3 shows a schematic diagram illustrating an assembly 300 according to a second embodiment; and

[0042] Figures 4a, 4b and 4c show schematic diagrams illustrating assemblies 400a, 400b, 400c according to further embodiments.

[0043] DETAILED DESCRIPTION OF EMBODIMENTS

[0044] In the following detailed description, reference is made to the accompanying drawings, which form a part thereof, and in which is shown by way of illustration specific aspects in which the disclosure may be practiced. It is understood that other aspects may be utilized and structural or logical changes may be made without departing from the scope of the disclosure. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the disclosure is defined by the appended claims.

[0045] It is understood that comments made in connection with a described method may also hold true for a corresponding device or system configured to perform the method and vice versa. For example, if a specific method step is described, a corresponding device may include a unit to perform the described method step, even if such unit is not explicitly described or illustrated in the figures. Further, it is understood that the features of the various exemplary aspects described herein may be combined with each other, unless specifically noted otherwise.

[0046] In this disclosure, power semiconductor modules and devices are described. A power semiconductor module is a package for power semiconductor devices. A power semiconductor module is generally designed to fulfil several purposes:

[0047] 1) It serves as a carrier for one or a multitude of electronic circuit elements, for example semiconductor chips (dies). The module with its circuit elements inside can be used to form electronic circuit in conjunction with other modules or can form (an) electric circuits) by itself.

[0048] 2) It provides a means of electrical interconnection of the chips inside to the terminals of the module, which connect the module to other electrically active parts of the circuit. The module also connects the chips (circuit elements) inside among each other if applicable.

[0049] 3) It can provide electrical isolation of the electrically active parts inside from the connection to the heat sink by separating the electrical connections from the cooling path with an isolator.

[0050] 4) It protects the circuit elements from environmental influences.

[0051] In order to fulfil functions 1 ) to 3), one or several substrates inside the module comprise an isolating layer (typically made of a ceramic or a plastic material) with layers of conductors on both sides (typically metal, commonly copper or aluminum). In the case where the isolating layer is a ceramic, this part of the module is referred to as metallized ceramic substrate. Metallized ceramic substrates can be categorized by composition and manufacturing method: - direct bonded copper (DBC),

[0052] - direct bonded aluminum (DBA),

[0053] - active metal brazing (AMB),

[0054] - metal casting direct bonding (MCB).

[0055] The metal layer on the top side of the substrate is often patterned. The resulting areas can form different electric potentials of an electric circuit. Chips and possibly other circuit elements are bonded (e. g. soldered, sintered or glued) with one of their electrodes onto the top side of the substrate. Heat generated by the chips (circuit elements) during operation is conducted through the isolating layer of the substrate towards a heat sink or the ambient.

[0056] Power modules or power semiconductor modules can comprise a base plate. Base plates are generally made of metal. They can fulfil several purposes such as being a carrier for one or several substrates, enhancing ruggedness and heat spreading. Substrates are bonded to the module base plate e. g. by soldering or sintering. Both baseplate and baseplate-less module designs are common.

[0057] An essential design feature of isolated power modules is the galvanic separation of the electrically active parts from the cooling path. All electrically active parts of the module are located on one side (in this disclosure: top) of the isolation layer. The base plate (if present) and heat sink is on the other side (in this disclosure: bottom).

[0058] To complete the power semiconductor module, the populated substrate is joined with a housing. Module housings are usually primarily made of a plastic material. Empty space inside the module is wholly or partly filled with a molding compound or another type of electrically isolating substance.

[0059] Eventually, the module is joined to a heat sink, typically made of metal. Baseplate- less modules can be bonded with or mounted onto heat sinks with the underside of their substrate. In baseplate modules, the baseplate is the interface to the heat sink. Common joining techniques are pressing, screwing, soldering and sintering.

[0060] Heat spreading perpendicular to the main direction of the heat transport has a significant effect on the chip temperatures. Lateral heat spreading enlarges the cross-sectional area through which the heat propagates and enters the successive (beneath) material layer. By placing heat sources (chips) far apart from each other, heat spreading can be achieved to some extent at the expense of a larger area requirement. Another approach is to include a heat spreader into the module, the heat sink, or in between the two. In its simplest form, a heat spreader can be a thick layer of material with a high thermal conductivity, e. g. metal such as copper. Vapor chambers achieve very effective lateral heat transport that cannot be reached with solid materials.

[0061] Vapor chambers as described in this disclosure are flat heat-transfer devices. They consist of a top plate and a bottom plate, either of which can be convex in shape. The two plates are tightly joined around the perimeter (e. g. through welding), forming a cavity. The cavity in between the plates contains a capillary structure (wick) and support structures (columns). The cavity is also filled with a small amount of a working fluid.

[0062] When heat enters the vapor chamber in a small area of the top side, the fluid in the vicinity of the hottest spot absorbs heat and evaporates. The vapor moves to the cooler areas within the vapor chamber (typically the edges), transporting heat with it. As the vapor condenses, it releases the heat that it previously absorbed. The fluid returns through capillary effect of the capillary structure. As the working fluid inside the vapor chamber circulates, absorbing heat in the hot locations and releasing it in the cooler areas, heat is transferred away from hottest area (heat source) to cooler areas. By way of utilizing convection, vapor chambers possess an exceptionally high heat transfer capability especially in lateral direction compared to any solid material, which rely on conduction. Therefore, they are highly suited to distribute heat and levelling out temperature gradients.

[0063] Figure 1 shows a schematic diagram illustrating an assembly 100 according to a first embodiment with a continuous top conductor layer 111.

[0064] The assembly 100 comprises a vapor chamber 120 with a top plate 113 and a bottom plate 114. One or both of the top and bottom plates 113, 114 are shaped such that a cavity 116 is formed between the tightly joined top and bottom plates 113, 114. The cavity 116 is filled with a fluid or working fluid, respectively.

[0065] The assembly 100 further comprises an electrically isolating layer 112 attached to one of the two plates, e.g., top plate 113 or bottom plate 114 of the vapor chamber 120. The electrically isolating layer 112 provides a mounting surface for electronic circuit elements that is electrically isolated from the vapor chamber 120.

[0066] One or both of the plates 113, 114 may be non- flat shaped in a lateral portion 116a of the vapor chamber 116 and may be flat in a central portion 116b of the vapor chamber 116. The electrically isolating layer 112 can be attached to a flat portion 116b of the vapor chamber 116 as shown in Figure 1.

[0067] The assembly 100 may comprise an electrically conductive layer 111 attached to the electrically isolating layer 112. The electrically isolating layer 112 can electrically isolate the electrically conductive layer 111 from the vapor chamber 120.

[0068] Although shown in Figure 1, this electrically conductive layer 111 is an optional layer that is not required for a basic configuration of the assembly 100. In such a basic configuration, the assembly 100 comprises the vapor chamber 120 and the electrically isolating layer 112 but not the electrically conductive layer 111.

[0069] Figure 2 shows a schematic diagram illustrating an assembly 200 according to the first embodiment with a patterned top conductor layer 111.

[0070] The assembly 200 corresponds to the assembly 100 described with respect to Figure 1 but has additional components. The assembly 200 comprises an electrically conductive layer 111 attached to the electrically isolating layer 112. The electrically isolating layer 112 is electrically isolating the electrically conductive layer 111 from the vapor chamber 120.

[0071] The assembly 200 comprises one or more electronic components 130a, 130b attached to the electrically conductive layer 111. In Figure 2 an exemplary number of two electronic components 130a, 130b are attached to the electrically conductive layer 111 but it can be any other number as well.

[0072] The electrically conductive layer 111 shown in Figure 2 comprises two or more segments I lla, 111b, 111c separated from each other, in Figure 2 an exemplary number of three such segments are shown, but it can be any other number as well.

[0073] At least one electronic component 130a, 130b can be attached to at least one segment of the two or more segments I lla, 111b, 111c. In Figure 2, no electronic component is attached to a first segment I lla, one electronic component 130b is attached to a second segment 111b and one electronic component 130a is attached to a third segment 111b of the electrically conductive layer 111 as an example configuration. Any other number of components and segments can be used as well. The assembly 200 may comprise a bonding layer 131 bonding the one or more electronic components 130a, 130b to the electrically conductive layer 111. The bonding layer 131 can also be divided into different segments depending on the segmentation of the conductive layer 111. In Figure 2 each electronic component 130a, 130b is placed on its own bonding layer segment. When placing two or more electronic components on the same segment of the electrically conductive layer 111, there can be a common bonding layer or some single or groups of electronic components can be placed on their own bonding layer segment, for example. Any configuration can be implemented.

[0074] The two or more segments I l la, 111b, 111c of the electrically conductive layer 111 can be at different electric potentials, for example. Accordingly, the assembly can be used to form an electronic circuit or part of an electronic circuit with different electric potentials.

[0075] These two or more segments I lla, 111b, 111c of the electrically conductive layer 111 can have different sizes, for example depending on the size and number of the electronic components placed thereupon.

[0076] The assembly 200 shown in Figure 2 may comprise at least one electronic component 130a, 130b. Figure 2 shows an example with two electronic components, but in another example, there can be only one electronic component.

[0077] The electronic components 130a, 130b can be, for example, of one or several of the following types: power semiconductor device, e. g. as described above, processor, integrated circuit, light emitting diode, resistor, inductor or capacitor.

[0078] The electronic components can be of the same type (for example power semiconductors) or of different types (e. g. some can be power semiconductors and other ones can be processors or passive components). There is no restriction in the choice of the electronic components.

[0079] Either or both of the electrically conductive layer 111 and the plate 113 of the vapor chamber 120, to which the electrically isolating layer 112 is attached, can be made of a metal, for example. The electrically isolating layer 112 can be made of a ceramic material, for example. At least one of the electrically conductive layer 111 and the plate 113 of the vapor chamber 120, to which the electrically isolating layer 112 is attached, can be interconnected with the electrically isolating layer 112 through a bond between ceramic and metal which can be fabricated by means of one of the following technologies, for example: direct bonded copper, DBC, direct bonded aluminum, DBA, active metal brazing, AMB, metal casting direct bonding, MCB. Any other suitable technologies can be applied, as well.

[0080] The cavity 116 of the vapor chamber 120 may comprise a support structure (not shown in the Figures) that is configured to support the top plate 113 and the bottom plate 114 of the vapor chamber 120 against deformation.

[0081] The vapor chamber 120 may be configured to dissipate heat generated by the electronic components 130a, 130b in lateral direction.

[0082] Thus, the first embodiment of the assembly 100, 200, as described with respect to Figures 1 and 2, may represent an assembly 100, 200 in which the vapor chamber 120 is directly attached to the underside of the isolation layer (e.g. electrically isolating layer 112) of a substrate or is formed with the bottom metal layer of a substrate as its top plate. One metal layer simultaneously serves as the bottom metal layer of the substrate and as the top plate of the vapor chamber.

[0083] The first embodiment of the assembly 100, 200 may correspond most closely to the common design of power semiconductor modules. It facilitates having areas of different electrical potential within the module. As a variation of embodiment 1 , the bottom plate 114 of the vapor chamber 120 can be bonded with or integrated into a heat sink.

[0084] Figure 3 shows a schematic diagram illustrating an assembly 300 according to a second embodiment.

[0085] The assembly 300 is another variation of the assemblies 100, 200 according to the first embodiment described with respect to Figures 1 and 2.

[0086] The assembly 300 according to the second embodiment shown in Figure 3 comprises one or more electronic components 130a, 130b attached to a first one 114 of the two plates 113, 114 of the vapor chamber 120 which is not attached to the electrically isolating layer 112. The assembly 300 comprises a bonding layer 131 bonding the one or more electronic components 130a, 130b to the first one 114 of the two plates 113, 114 of the vapor chamber 120.

[0087] Another difference of the second embodiment is that in this second embodiment both plates 113, 114 of the vapor chamber 120 are non-flat shaped, while in the first embodiment shown in Figures 1 and 2, only the top plate 113 of the vapor chamber is non-flat shaped, while the bottom plate 114 is flat shaped.

[0088] This second embodiment shows an assembly as described above in which the vapor chamber 120 is directly attached to the underside of the isolation layer (e.g. electrically isolating layer 112) of a substrate or is formed with the bottom metal layer of the substrate as its top plate. One metal layer simultaneously serves as the bottom plate of the vapor chamber and as the top metal layer of the substrate.

[0089] Figures 4a, 4b and 4c show schematic diagrams illustrating assemblies 400a, 400b, 400c according to further embodiments. The assemblies 400a, 400b, 400c show further variations of the assemblies 100, 200, 300 described above with respect to Figures 1 to 3.

[0090] In the assembly 400a shown in Figure 4a, the vapor chamber 120 is turned upside down compared to the assembly 100 shown in Figure 1 and the electrically isolating layer 112 is attached to the flat plate 114 instead of the non-flat plate 113.

[0091] The assembly 400b shown in Figure 4b corresponds to the assembly 400a shown in Figure 4a, but the electrically isolating layer 112 extends beyond the edges of the flat plate 114 of the vapor chamber 120.

[0092] The assembly 400c shown in Figure 4c corresponds to the assembly 400a shown in Figure 4a, but both plates 114 and 113 of the vapor chamber 120 are non-flat shaped.

[0093] The assemblies described in this disclosure can be generally applied for transfer of heat between parts of different dimensions through a layer of electrically isolating material. They can also be generally applied for cooling localized heat sources, with a high heat flux density, where electrical isolation in the cooling path is desired. They can be applied more specifically for cooling various types of electronic components, for example power semiconductor devices, processors (integrated circuits), light emitting diodes, laser diodes, resistors, etc.

[0094] While a particular feature or aspect of the disclosure may have been disclosed with respect to only one of several implementations, such feature or aspect may be combined with one or more other features or aspects of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms "include", "have", "with", or other variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term "comprise". Also, the terms "exemplary", "for example" and "e. g." are merely meant as an example, rather than the best or optimal. The terms “coupled” and “connected”, along with derivatives may have been used. It should be understood that these terms may have been used to indicate that two elements cooperate or interact with each other regardless whether they are in direct physical or electrical contact, or they are not in direct contact with each other.

[0095] Although specific aspects have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations may be substituted for the specific aspects shown and described without departing from the scope of the disclosure. This application is intended to cover any adaptations or variations of the specific aspects discussed herein.

[0096] Although the elements in the following claims are recited in a particular sequence with corresponding labeling, unless the claim recitations otherwise imply a particular sequence for implementing some or all of those elements, those elements are not necessarily intended to be limited to being implemented in that particular sequence.

[0097] Many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the above teachings. Of course, those skilled in the art readily recognize that there are numerous applications of the disclosure beyond those described herein. While the disclosure has been described with reference to one or more particular embodiments, those skilled in the art recognize that many changes may be made thereto without departing from the scope of the disclosure. It is therefore to be understood that within the scope of the appended claims and their equivalents, the disclosure may be practiced otherwise than as specifically described herein.

Claims

CLAIMS:

1. An assembly (100, 200, 300), comprising: a vapor chamber (120) comprising a top plate (113) and a bottom plate (114); wherein one or both of the top and bottom plates (113, 114) are shaped such that a cavity (116) is formed between the tightly joined top and bottom plates (113, 114); wherein the cavity (116) is filled with a working fluid; and an electrically isolating layer (112) attached to one of the two plates (113, 114) of the vapor chamber (120), the electrically isolating layer (112) providing a mounting surface that is electrically isolated from the vapor chamber (120).

2. The assembly (100, 200, 300) of claim 1, wherein one or both of the plates (113, 114) are non- flat shaped in a lateral portion (116a) of the vapor chamber (116) and are flat in a central portion (116b) of the vapor chamber (116); wherein the electrically isolating layer (112) is attached to a flat portion (116b) of the vapor chamber (116).

3. The assembly (100, 200, 300) of claim 1 or 2, comprising: an electrically conductive layer (111) attached to the electrically isolating layer (112); wherein the electrically isolating layer (112) is electrically isolating the electrically conductive layer (111) from the vapor chamber (120).

4. The assembly (200) of claim 3, comprising: one or more electronic components (130a, 130b) attached to the electrically conductive layer (111).

5. The assembly (200) of claim 4, comprising: a bonding layer (131) bonding the one or more electronic components (130a, 130b) to the electrically conductive layer (111).

6. The assembly (200) of claim 4 or 5, wherein the electrically conductive layer (111) comprises two or more segments (I l la, 111b, 111c) separated from each other; wherein at least one electronic component (130a, 130b) is attached to at least one segment of the two or more segments (I lla, 111b, 111c).

7. The assembly (200) of claim 6, wherein the two or more segments (Il la, 111b, l l lcj ofthe electrically conductive lay er ( 111 ) are at different electric potentials.

8. The assembly (200) of claim 6 or 7, wherein the two or more segments (I l la, 111b, 111c) of the electrically conductive layer (111) have different sizes.

9. The assembly (200) of any of the preceding claims, comprising at least one electronic component (130a, 130b).

10. The assembly (200) of claim 9, wherein the electronic components (130a, 130b) are of one or several of the following types: power semiconductor device, processor, integrated circuit, light emitting diode, resistor, inductor or capacitor.

11. The assembly (300) of any of the preceding claims, comprising: one or more electronic components (130a, 130b) attached to a first one (114) of the two plates (113, 114) of the vapor chamber (120) which is not attached to the electrically isolating layer (112); and a bonding layer (131) bonding the one or more electronic components (130a, 130b) to the first one (114) of the two plates (113, 114) of the vapor chamber (120).

12. The assembly (100, 200, 300) of any of claims 3 to 8, wherein either or both of the electrically conductive layer (111) and the plate (113) of the vapor chamber (120), to which the electrically isolating layer (112) is attached, are made of a metal, wherein the electrically isolating layer (112) is made of a ceramic material, wherein at least one of the electrically conductive layer (111) and the plate (113) of the vapor chamber (120), to which the electrically isolating layer (112) is attached, is interconnected with the electrically isolating layer (112) through a bond between ceramic and metal which is fabricated by means of one of the following technologies: direct bonded copper, DBC, direct bonded aluminum, DBA, active metal brazing, AMB, metal casting direct bonding, MCB.

13. The assembly (100, 200, 300) of any of the preceding claims, wherein the cavity (116) of the vapor chamber (120) comprises a support structure that is configured to support the top plate (113) and the bottom plate (114) of the vapor chamber (120) against deformation.

14. The assembly (100, 200, 300) of any of claims 4 to 10, wherein the vapor chamber (120) is configured to dissipate heat generated by the electronic components (130a, 130b) in lateral direction.

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