Power electronics assemblies incorporating power electronics devices

By using S cells containing graphic layers and metal layers in power electronic devices and forming thermal conduction holes on the circuit board, the heat is directed to the cooling plate, the problem of high thermal impedance of power electronic devices under compact packaging size is solved, and more efficient thermal conductivity and cooling effects are achieved.

JP7659025B2Active Publication Date: 2025-04-08TOYOTA JIDOSHA KK +2
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Patent Information

Application Number
JP2023173538
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2022-10-17
Filing Date
2023-10-05
Publication Date
2025-04-08
Estimated Expiration
2043-10-05

AI Technical Summary

Technical Problem

The prior art is difficult to effectively reduce the thermal impedance of power electronic equipment in electric vehicles while maintaining a compact packaging size.

Method used

S cells containing a pattern layer and a metal layer are used as the supporting structure of the power electronics device, and heat is directed to the cooling plate by forming thermal vias on the circuit board.

Benefits of technology

Improves the thermal conductivity and cooling effect of power electronic equipment, reduces overall thermal impedance, while maintaining a compact packaging size.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To improve cooling of power electronics devices while maintaining compact package size.SOLUTION: A power electronics assembly includes a circuit board assembly. The circuit board assembly includes a first electrically insulating layer, an electrically insulating substrate, a laminate panel provided between the first electrically insulating layer and the electrically insulating substrate, and one or more electrically conductive layers provided within the electrically insulating substrate. The laminate panel includes a power electronics device assembly including an S-cell and a power electronics device. The S-cell includes a graphite layer and a metal layer covering the graphite layer. A recess is formed in an outer surface of the metal layer, and the power electronics device is disposed within the recess of the outer surface of the S-cell.SELECTED DRAWING: Figure 1
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Description

[Technical field]

[0001] The present specification relates generally to power electronic assemblies, and more particularly to an apparatus and method for a power electronics assembly that achieves a compact package size while having a low overall thermal resistance. [Background technology]

[0002] The increasing use of electronics in vehicles requires that electronic systems be made more compact. One of the components of such electronic systems are power electronic devices used as switches in inverters. Power electronic devices generate heat and therefore require a lot of cooling.

[0003] Additionally, power electronic devices traditionally constructed from silicon are now trending to be constructed from silicon carbide, which defines a smaller device footprint and therefore results in higher heat fluxes. For these reasons and more, there is a need to improve the cooling of power electronic devices while maintaining a compact package size. Summary of the Invention

[0004] In one embodiment, a power electronics assembly includes a circuit board assembly including a first electrically insulating layer, an electrically insulating substrate, a laminate panel disposed between the first electrically insulating layer and the electrically insulating substrate, and one or more electrically conductive layers disposed within the electrically insulating substrate, the laminate panel including a power electronics device assembly including an S-cell including a graphite layer and a metal layer overlying the graphite layer, with a recess formed in an outer surface of the metal layer, and a power electronics device disposed within the recess in the outer surface of the S-cell.

[0005] In another embodiment, a power electronics assembly includes a circuit board assembly including a first electrically insulating layer, an electrically insulating substrate, a laminate panel disposed between the first electrically insulating layer and the electrically insulating substrate, one or more electrically conductive layers disposed within the electrically insulating substrate, a plurality of thermal vias thermally connecting each of the power electronic devices to the one or more electrically conductive layers, and a cooling plate, the laminate panel including a plurality of power electronic device assemblies, each power electronic device assembly including an S-cell including a graphite layer and a metal layer overlying the graphite layer, the S-cell having a recess formed in an outer surface of the metal layer, and a power electronic device disposed within the recess in the outer surface of the S-cell, the metal layer of each S-cell bonded to the circuit board assembly being bonded to a first surface of the cooling plate through the first electrically insulating layer.

[0006] In yet another embodiment, a method includes providing a first electrically insulating layer on a first side of a cold plate; providing a laminate panel on the first electrically insulating layer opposite the cold plate, the laminate panel including a power electronics device assembly including an S-cell including a graphite layer and a metal layer overlying the graphite layer, the S-cell having a recess formed in an outer surface of the metal layer, and a power electronics device disposed in the recess in the outer surface of the S-cell; laminating a first two-layer circuit pair on the laminate panel opposite the first electrically insulating layer; laser drilling vias through the first two-layer circuit pair; and filling the vias with an electrically conductive material to thermally connect the first two-layer circuit pair to the power electronics device.

[0007] These and additional features provided by the embodiments described herein will be more fully understood when considered in conjunction with the drawings and the following detailed description. [Brief description of the drawings]

[0008] The embodiments set forth in the drawings are illustrative and exemplary in nature and are not intended to limit the subject matter defined by the claims. The following detailed description of illustrative embodiments can be understood when read in conjunction with the following drawings, in which like structure is designated with like reference numerals and in which: [Figure 1] FIG. 1 illustrates generally an assembled perspective view of a power electronics assembly including a cold plate and circuit board assembly according to one or more embodiments described and illustrated herein. [Diagram 2] FIG. 2 illustrates generally an exploded perspective view of the power electronics assembly of FIG. 1 according to one or more embodiments described and illustrated herein. [Diagram 3] FIG. 3 illustrates a schematic diagram of a partial perspective view of a cold plate of the power electronics assembly of FIG. 1 according to one or more embodiments described and illustrated herein. [Figure 4] FIG. 4 illustrates a schematic exploded perspective view of a power electronics device assembly including an S-cell and a power electronics device according to one or more embodiments described and illustrated herein. [Diagram 5] FIG. 5 illustrates a schematic cross-sectional view of the power electronics device assembly of FIG. 4 according to one or more embodiments described and illustrated herein. [Figure 6] FIG. 6 illustrates a schematic diagram of a partial perspective view of the power electronics assembly of FIG. 1 including a cold plate and a laminate layer including multiple power electronic device assemblies according to one or more embodiments described and illustrated herein. [Figure 7] FIG. 7 illustrates generally an exploded cross-sectional view of the power electronics assembly of FIG. 1 showing a first two-layer circuit pair of a circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 8] FIG. 8 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing a first two-layer circuit pair of the circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 9] FIG. 9 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing vias formed through a first two-layer circuit pair of the circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 10] FIG. 10 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing the vias of FIG. 9 filled, according to one or more embodiments described and illustrated herein. [Figure 11] FIG. 11 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing etching of a first two-layer circuit pair of a circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 12] FIG. 12 illustrates generally an exploded cross-sectional view of the power electronics assembly of FIG. 1 showing a second two-layer circuit pair of the circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 13] FIG. 13 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing a second two-layer circuit pair of the circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 14] FIG. 14 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing vias formed through a second two-layer circuit pair of the circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 15] FIG. 15 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing the vias of FIG. 14 filled, according to one or more embodiments described and illustrated herein. [Figure 16] FIG. 16 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 showing etching of a second two-layer circuit pair of the circuit board assembly according to one or more embodiments described and illustrated herein. [Figure 17]FIG. 17 illustrates a schematic cross-sectional assembled view of the power electronics assembly of FIG. 1 including multiple surface mounted electronics according to one or more embodiments described and illustrated herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The embodiments described herein are generally directed to a power electronics assembly having a circuit board assembly connected to a cold plate, the circuit board assembly including a power electronics device assembly including an S-cell. The power electronics device may be embedded within the S-cell.

[0010] The power electronic device assembly of the present disclosure includes a power electronic device attached to a mounting substrate, referred to herein as an S-cell. As described in more detail below, the S-cell includes a graphite layer that provides enhanced heat spreading capabilities. Additionally, embodiments of the present disclosure include one or more electrical insulation layers that electrically insulate the power electronic device from the cold plate. For example, the electrical insulation layer of the S-cell allows for the elimination of an electrical insulation layer between the printed circuit board and the cold plate, since the electrical insulation is provided by the S-cell itself.

[0011] As described in more detail below, the S-cells of the present disclosure provide enhanced thermal properties due to the graphite layer that encourages heat flux flow towards the cold plate. The S-cells described herein include laminated metal, graphite, and one or more electrically insulating layers in a compact package. The bonding materials described herein for bonding the S-cells are specifically configured to increase thermal conductivity relative to other bonding techniques while also maintaining the ability to electrically insulate the S-cells. The devices, systems, and apparatus described herein improve the heat flux from the S-cells to the cold plate, thereby increasing the heat spreading and cooling performance for the circuit board assembly.

[0012] The cold plates, power electronic device assemblies, circuit board assemblies, power electronics assemblies, and the like described herein may be used in electrified vehicles, such as, but not limited to, electric vehicles, hybrid electric vehicles, any electric motors, generators, industrial tools, household appliances, and the like. The various assemblies described herein may be electrically connected to an electric motor and / or a battery and may be configured as an inverter circuit operable to convert direct current (DC) power to alternating current (AC) power.

[0013] As used herein, "power electronic device" refers to any electrical component used to convert DC power to AC power and vice versa. Embodiments may also be employed in AC-AC converter and DC-DC converter applications. Non-limiting examples of power electronic devices include power metal oxide semiconductor field effect transistors (MOSFETs), insulated gate bipolar transistors (IGBTs), thyristors, and power transistors.

[0014] As used herein, the phrase "fully embedded" means that a component is surrounded on each side by a substrate. For example, if a power electronics device assembly is fully embedded by a circuit board, it means that the material of the circuit board covers each side of the circuit board. If one or more sides of the component are exposed, the component is "partially embedded."

[0015] As used herein, an "S-cell" is a mounting substrate operable to be attached to a power electronic device and includes one or more of a metal layer, a graphite layer, and an electrically insulating layer.

[0016] Various embodiments of the power electronics assembly, the power electronics device assembly, and the cold plate are described in detail below. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like parts.

[0017] 1 and 2, an exemplary power electronics assembly 100 is generally shown in assembled and exploded views, respectively. The power electronics assembly 100 shown in FIGS. 1 and 2 includes a cold plate 102 and a circuit board assembly 106. The cold plate 102 can be any device capable of removing heat flux from a power electronics device 140 (see FIG. 4) connected to a substrate material of the circuit board assembly 106. Non-limiting examples for the cold plate 102 include heat sinks, single-phase liquid cooling, two-phase liquid cooling, and vapor chambers. FIGS. 1 and 2 show the cold plate 102 configured as a single-phase liquid cooling device. The cold plate 102 includes a fluid inlet 132 and a fluid outlet 134 fluidly connected to a fluid chamber 115 (FIG. 7) within the cold plate 102. Although FIGS. 1 and 2 show the fluid inlet 132 and the fluid outlet 134 on the same side of the cold plate 102, the present disclosure is not limited to such an embodiment. That is, in other embodiments, the fluid inlet 132 and the fluid outlet 134 may be located on other faces.

[0018] 1 and 2, the circuit board assembly 106 is connected (e.g., attached) to a first side 107 of the cold plate 102. Figures 1 and 2 show the circuit board assembly 106 as being attached to the first side 107 of the cold plate 102 by fasteners 101 (e.g., bolts and nuts) that extend through through holes 105 in the cold plate 102 and through holes 109 in the circuit board assembly 106. It should be understood that in other embodiments, the through holes 105, 109 and fasteners 101 may be omitted, as described below.

[0019] In an embodiment, the circuit board assembly 106 may be a 3D printed layer. It should be appreciated that in such an embodiment, the 3D printed layer of the circuit board assembly 106 reduces the overall thermal resistance. In an embodiment, the circuit board assembly 106 may be laminated to the cold plate 102. However, other additive manufacturing processes for attaching the circuit board assembly 106 to the cold plate 102 are also envisioned and are within the scope of the present disclosure. In addition, as described in more detail herein, via connections or vias may be made between various components of the circuit board assembly 106 and the power electronic device 140 (FIG. 4) using laser drilling. That is, vias are drilled through the circuit board assembly 106 to each conductive layer and to the top surface of the power electronic device 140. As described in more detail herein, the vias are then filled with copper by an electroplating process to establish electrical connections between the components. The circuit board assembly 106 is generally shown in FIGS. 1 and 2, while the individual layers and various steps of the assembly are shown in FIGS. 6-17.

[0020] 3-17, the individual steps of manufacturing the power electronics assembly 100 are shown. As shown in FIG. 3, a first electrical insulation layer 180 is shown deposited on a first surface 107 of the cold plate 102 to reduce the thermal resistance between the circuit board assembly 106 and the cold plate 102 (FIG. 1). The first electrical insulation layer 180 can generally be any layer that provides electrical insulation, such as ceramic or the like. In an embodiment, the first electrical insulation layer 180 includes an insulated metal substrate (IMS) dielectric film. The IMS dielectric film can be a solid film layer. In other embodiments, the first electrical insulation layer 180 can be a thermal grease layer. It should be noted that the first electrical insulation layer 180 does not have to have a dedicated through hole.

[0021] 4 and 5, there are shown an exploded top perspective view and an assembled cross-sectional view, respectively, of an exemplary S-cell 121. The S-cell 121 includes a plurality of stacked layers. In particular, the S-cell 121 shown in FIGS. 4 and 5 includes a metal layer 122 and a graphite layer 124 embedded within the metal layer 122. The metal layer 122 includes an inner surface 125 and an outer surface 128 opposite the inner surface 125. In an embodiment, the metal layer 122 includes a first metal layer and a second metal layer, and the graphite layer 124 is located between the first metal layer and the second metal layer. The metal layer 122 includes a recess 127 disposed within the outer surface 128 of the metal layer 122. The recess 127 is dimensioned to receive a power electronic device 140. As described in more detail below, metal layer 122 provides an electrically conductive surface to which electrodes at the bottom side of power electronic device 140 are connected (e.g., via direct connections and / or electrical connection vias). It should be understood that the various layers of S-cell 121 shown in Figures 4 and 5 are merely exemplary. That is, in some embodiments, for example, S-cell 121 may include multiple graphite and / or other layers disposed between metal layers.

[0022] It should be noted that the S-cell 121 in the embodiment of Figures 4 and 5 includes a graphite layer 124 embedded within the metal layer 122 to provide the S-cell 121 with symmetry along the z-axis of the coordinate axes shown in Figures 4 and 5. The symmetry of the S-cell 121 balances the forces on the S-cell 121 during the high temperature bonding process. Because the metal layer 122 and the graphite layer 124 have different thermal expansion coefficients, it may be desirable to have a symmetrical substrate stack to balance thermally induced stresses during the bonding process.

[0023] The metal layer 122 may be made of any suitable metal or alloy. As a non-limiting example, copper and aluminum may be used as the metal layer. The metal layer 122 of the S-cell 121 has a recess 127 formed in its outer surface 128. The recess 127 may be formed, for example, by chemical etching. The recess 127 has a size and shape to receive the power electronic device 140. The outer surface 128 may generally be a second major surface or face of the metal layer 122 opposite the inner surface 125 (configured as the first major surface or face of the metal layer 122). That is, the metal layer 122 may be a planar layer, whereby the inner surface 125 faces the graphite layer 124 and the opposite outer surface 128 faces the power electronic device 140 and the circuit board assembly 106 (FIG. 7).

[0024] The graphite layer 124 shown in the embodiment of FIG. 5 is provided to facilitate both thermal diffusion across the S-cell 121 and towards the cold plate 102 (see, for example, FIG. 7). The crystalline structure of graphite provides it with high thermal conductivity, making it useful for conducting heat flux towards the cold plate 102. However, graphite does not have an isothermal profile. Rather, graphite has a non-isothermal profile, with high conductivity along two axes and low thermal conductivity in the third axis. To take into account the non-isothermal profile of graphite, the S-cell 121 is designed to be rectangular in shape such that the length dimension of the S-cell 121 is greater than the width dimension of the S-cell 121. With reference to FIG. 5, the graphite layer 124 has high thermal conductivity along the x-axis and z-axis of the coordinate axes shown in FIG. 5. Thus, the S-cell 121 is designed such that the dimension of the S-cell 121 along the x-axis is greater than the dimension of the S-cell 121 along the y-axis. Heat flux travels along the x-axis and the z-axis. As described in more detail below, heat flux is transferred along the x-axis by the S-cell 121 towards the cold plate 102. Heat flux also travels along the z-axis towards the cold plate 102.

[0025] Referring again to FIG. 4, an exploded view of a power electronic device assembly 146 including the S-cell 121 and the power electronic device 140 is shown. FIG. 4 shows the power electronic device 140 and the bonding layer 143 relative to the recess 127 of the S-cell 121. For example, the bonding layer 143 can be a solder layer. As another example, the bonding layer 143 can be a transient liquid phase bonding layer 143. The power electronic device 140 includes a plurality of large electrodes 141 and a plurality of small electrodes 142 on its top surface. The large electrodes 141 can be power electrodes, while the small electrodes 142 can be signal electrodes. It should be noted that, although not visible in FIG. 4, the power electronic device 140 further includes one or more electrodes on its bottom surface. The one or more electrodes on the bottom surface of the power electronic device 140 are electrically connected to the metal layer 122 by placing the power electronic device 140 in the recess 127. Thus, the electrical connection of the power electronic device 140 to the bottom electrode can be made by the metal layer 122.

[0026] As mentioned above, the S-cell 121 is the substrate to which the power electronic device 140 is bonded. The S-cell 121 provides an electrically conductive surface area for making connections to electrodes on the bottom side of the power electronic device 140. The S-cell 121 also provides a heat spreading function and electrical insulation.

[0027] 6, a laminate panel 200 including one or more power electronic device assemblies 146 surrounded by a laminate material 202 is disposed on a first electrical insulation layer 180 opposite the cold plate 102. In an embodiment, the laminate material 202 includes FR-4, although alternative materials are within the scope of the present disclosure. As shown, a total of six power electronic device assemblies 146 are disposed in two rows of three and bonded to the cold plate 102 via the first electrical insulation layer 180 and the laminate material 202. However, it should be understood that any number of power electronic device assemblies 146 may be utilized depending on the application.

[0028] 7, a cross-sectional view of the power electronics assembly 100 is shown. Cooling fluid (indicated as moving arrow 135) from a reservoir (not shown) flows through fluid inlet 132 into fluid chamber 115 and exits fluid chamber 115 through fluid outlet 134 as a warmed cooling fluid that is returned to the reservoir after flowing, for example, through a heat exchanger (not shown) to remove heat from cooling fluid 135. Although not shown, an array of fins may be provided in fluid chamber 115 to provide additional surface area for heat transfer to cooling fluid 135.

[0029] As shown, the laminate panel 200 is disposed between a first electrically insulating layer 180 and a second electrically insulating layer 204. It should be understood that the second electrically insulating layer 204 may comprise the same material as the first electrically insulating layer 180.

[0030] 7, a first two-layer circuit pair 206 is shown positioned above the second electrically insulating layer 204 to form the circuit board assembly 106. The first two-layer circuit pair 206 includes a first electrically conductive layer 208 and a second electrically conductive layer 210 laminated therebetween with a third electrically insulating layer 212. In an embodiment, the first electrically conductive layer 208 and the second electrically conductive layer 210 are copper layers. The first electrically conductive layer 208 is etched into a designated pattern to conduct electrical current, while the second electrically conductive layer 210 remains unetched.

[0031] 8, the first two-layer circuit pair 206 is positioned on the second electrically insulating layer 204. The first two-layer circuit pair 206 is laminated to the second electrically insulating layer 204 in a high temperature and pressure chamber. During this lamination step, material from the second electrically insulating layer 204 and the third electrically insulating layer 212 fills the gaps defined by the etching of the first electrically conductive layer 208.

[0032] 9, the vias 112 are formed to extend between any combination of the power electronic devices 140, the first electrically conductive layer 208, and the second electrically conductive layer 210 of the power electronic device assembly 146. For example, the vias 112 are shown extending through the first electrically conductive layer 208 between the power electronic devices 140 and the second electrically conductive layer 210 of each power electronic device assembly 146. Additionally, the vias 112 (both electrically conductive vias and thermal vias) are shown extending between the first electrically conductive layer 208 and the second electrically conductive layer 210 without intersecting with the power electronic devices 140. The vias 112 may be formed in any suitable manner, such as, for example, laser drilling. It should be understood that the scope of the present disclosure is not limited to the particular configuration of the vias 112 shown in FIG. 9, and other configurations are contemplated based on the unique demands of the circuit board assembly 106.

[0033] The vias 112 may provide a current path for the switching current as well as provide a drive signal to the power electronic device 140. Note that in some embodiments, some of the vias 112 may be configured as thermal vias that do not carry a drive signal or switching current. In addition, the arrangement of the S-cells allows for flux transfer from the power electronic device 140 to the cold plate 102 through the S-cells 121 as described herein. In this way, heat flux is optimally directed away from the power electronic device 140 through the S-cells 121 to the cold plate 102.

[0034] 10, the vias 112 are filled with copper by electroplating to form electrical connections between each power electronic device assembly 146, the first electrically conductive layer 208, and the second electrically conductive layer 210. However, it should be understood that the vias 112 may be filled in any other suitable manner other than electroplating.

[0035] 11, after the first two-layer circuit pair 206 is laminated to the laminate panel 200 via the second electrically insulating layer 204, the second electrically conductive layer 210 may be etched into a desired configuration based on the specifications of the circuit board assembly 106. It should be understood that the circuit board assembly 106 may include any number of electrically conductive layers. For example, the circuit board assembly 106 may include only the first electrically conductive layer 208 and the second electrically conductive layer 210. In such an embodiment, one or more surface mount electronics (such as the surface mount electronics 214 shown in FIG. 17), such as, for example, transistors, resistors, capacitors, and the like, may be mounted on the second electrically conductive layer 210. However, in other embodiments, the circuit board assembly 106 may include multiple two-layer circuit pairs, and the surface mount electronics may be mounted on the topmost electrically conductive layer. In doing so, the steps described herein with respect to Figures 7-11 may be repeated with each additional two-layer circuit pair being laminated to the previous two-layer circuit pair.

[0036] For example, referring now to Figure 12, a fourth electrical insulation 216 is provided on the second electrically conductive layer of the first two-layer circuit pair 206, and a second two-layer circuit pair 218 is shown positioned above the first two-layer circuit pair 206. The second two-layer circuit pair 218 includes a third electrically conductive layer 220 and a fourth electrically conductive layer 222 laminated therebetween with a fifth electrically insulating layer 224. In an embodiment, the third electrically conductive layer 220 and the fourth electrically conductive layer 222 are copper layers. The third electrically conductive layer 220 is etched into a designated pattern to conduct electrical current, while the fourth electrically conductive layer 222 remains unetched.

[0037] 13, the second two-layer circuit pair 218 is positioned on the first two-layer circuit pair 206. The second two-layer circuit pair 218 is laminated to the first two-layer circuit pair 206 in a high temperature and pressure chamber. During this lamination step, material from the second electrically insulating layer 204 and the third electrically insulating layer 212 fills the gaps defined by the etching of the second electrically conductive layer 210. Additionally, material from the fourth electrically insulating layer 216 and the fifth electrically insulating layer 224 fills the gaps defined by the etching of the third electrically conductive layer 220. It should be appreciated that in an embodiment, the electrically insulating layers 204, 212, 216, 224 form an integral, monolithic electrically insulating substrate such that the laminate panel 200, and in particular the power electronics device assembly 146, is disposed within the electrically insulating substrate.

[0038] 14, additional vias 112 are formed to extend between any combination of the first electrically conductive layer 208, the second electrically conductive layer 210, the third electrically conductive layer 220, and the fourth electrically conductive layer 222. For example, the vias 112 are shown extending through the third electrically conductive layer 220 between the second electrically conductive layer 210 and the fourth electrically conductive layer 222. Additionally, the vias 112 are shown extending between the third electrically conductive layer 220 and the fourth electrically conductive layer 222 without intersecting with the power electronic device 140, the first electrically conductive layer 208, or the second electrically conductive layer 210. As described herein, it should be understood that the scope of the present disclosure is not limited to the particular configuration of the vias 112 shown in FIG. 14, and other configurations are contemplated based on the unique demands of the circuit board assembly 106.

[0039] 15, as described herein, the vias 112 are filled with copper by electroplating to form electrical connections between each power electronics device assembly 146, the first electrically conductive layer 208, the second electrically conductive layer 210, the third electrically conductive layer 220, and the fourth electrically conductive layer 222, either directly or indirectly.

[0040] Then, as shown in FIG. 16, after the second two-layer circuit pair 218 is laminated to the first two-layer circuit pair 206 via the fourth electrically insulating layer 216, the fourth electrically conductive layer 222 can be etched into a desired configuration based on the specifications of the circuit board assembly 106.

[0041] 17, one or more surface mount electronics 214 may be mounted to the fourth electrically conductive layer 222. As described herein, the surface mount electronics 214 may include, for example, transistors, resistors, capacitors, and the like. Thus, it should be understood that the circuit board assembly 106 includes at least the laminate panel 200 including the plurality of power electronic device assemblies 146, the first two-layer circuit pair 206, the second two-layer circuit pair 218, and the surface mount electronics 214.

[0042] From the above, it should be appreciated that a power electronics assembly and a method for manufacturing a power electronics assembly are defined herein. Specifically, the power electronics assembly disclosed herein includes a circuit board assembly, the circuit board assembly including a first electrically insulating layer, an electrically insulating substrate, a laminate panel disposed between the first electrically insulating layer and the electrically insulating substrate, and one or more electrically conductive layers disposed within the electrically insulating substrate. The laminate panel includes a power electronics device assembly including an S-cell and a power electronics device. The S-cell includes a graphite layer and a metal layer covering the graphite layer. A recess is formed in an outer surface of the metal layer, and the power electronics device is disposed within the recess in the outer surface of the S-cell.

[0043] It should be appreciated that embodiments of the present disclosure are directed to a power electronics assembly having a circuit board assembly connected to a power electronics device assembly including a cold plate housing an S-cell. The power electronics device may be embedded within the S-cell and / or within the circuit board assembly. Such a power electronics assembly is compact and provides increased thermal conductivity while maintaining the ability to electrically isolate the S-cells, thereby improving heat flux from the S-cells to the cold plate, thereby increasing the heat spreading and cooling capabilities of the circuit board assembly relative to conventional packages.

[0044] It should be noted that the terms "substantially" and "about" may be utilized herein to express the degree of inherent uncertainty that may result from any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to express the degree to which a quantitative representation may vary from the stated basis without resulting in a change in the basic functionality of the subject matter at issue.

[0045] While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications can be made without departing from the scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.

[0046] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the scope of the claimed subject matter. Thus, the present specification is intended to cover modifications and variations of the various embodiments described herein, provided that such modifications and variations come within the scope of the appended claims and their equivalents.

Claims

1. 1. A power electronics assembly comprising a circuit board assembly, the circuit board assembly comprising: a first electrically insulating layer; An electrically insulating substrate; a laminate panel disposed between the first electrically insulating layer and the electrically insulating substrate; one or more electrically conductive layers disposed within the electrically insulating substrate; Equipped with the laminate panel comprises a power electronic device assembly; The power electronic device assembly includes: An S cell, A graphite layer; a metal layer covering the graphite layer; an S cell comprising: a power electronics device disposed within the recess in the outer surface of the S cell. Power electronics assembly.

2. The laminate panel comprises: A laminate material; a plurality of power electronic device assemblies embedded within the laminate material; Equipped with 10. The power electronics assembly of claim 1.

3. The laminate material comprises FR-4.

3. The power electronics assembly of claim 2.

4. the first electrically insulating layer and the electrically insulating substrate each comprise an insulated metal substrate dielectric film; 10. The power electronics assembly of claim 1.

5. the circuit board assembly further comprising a plurality of vias extending through the electrically insulating substrate to thermally connect the power electronic device to the one or more electrically conductive layers.

10. The power electronics assembly of claim 1.

6. The S cell has a length greater than a width of the S cell.

10. The power electronics assembly of claim 1.

7. a cooling plate, the circuit board assembly being bonded to a surface of the cooling plate by the first electrically insulating layer.

10. The power electronics assembly of claim 1.

8. 1. A power electronics assembly comprising a circuit board assembly, the circuit board assembly comprising: a first electrically insulating layer; An electrically insulating substrate; a laminate panel disposed between the first electrically insulating layer and the electrically insulating substrate, the laminate panel comprising a plurality of power electronic device assemblies, each power electronic device assembly comprising: An S cell, A graphite layer; a metal layer covering the graphite layer; an S cell comprising: a power electronics device disposed within the recess in the outer surface of the S cell; one or more electrically conductive layers disposed within the electrically insulating substrate; a plurality of thermal vias thermally connecting each of the power electronic devices to the one or more electrically conductive layers; A cooling plate; the metal layer of each S cell bonded to the circuit board assembly is bonded to the first surface of the cooling plate via the first electrically insulating layer; Power electronics assembly.

9. the laminate panel comprises a laminate material; the plurality of power electronic device assemblies are embedded within the laminate material; 9. The power electronics assembly of claim 8.

10. The laminate material comprises FR-4.

10. The power electronics assembly of claim 9.

11. the first electrically insulating layer and the electrically insulating substrate each comprise an insulated metal substrate dielectric film; 9. The power electronics assembly of claim 8.

12. The S cell has a length greater than a width of the S cell.

6. A power electronics assembly according to claim 5.

13. providing a first electrically insulating layer on a first surface of the cooling plate; providing a laminate panel on the first electrically insulating layer opposite the cold plate, the laminate panel comprising a power electronics device assembly, the power electronics device assembly comprising: An S cell, A graphite layer; a metal layer covering the graphite layer; an S cell comprising: a power electronics device disposed within the recess in the outer surface of the S cell; laminating a first two-layer circuit pair onto the laminate panel opposite the first electrically insulating layer; laser drilling vias through the first two-layer circuit pair; filling the vias with an electrically conductive material to thermally couple the first two-layer circuit pair to the power electronics device; A method comprising:

14. further comprising laminating a second two-layer circuit pair onto the first two-layer circuit pair opposite the laminate panel. The method of claim 13.

15. further comprising laser drilling vias through the second two-layer circuit pair. The method of claim 14.

16. and filling the vias extending through the second two-layer circuit pair with the electrically conductive material to thermally connect the second two-layer circuit pair to the first two-layer circuit pair. The method of claim 15.

17. mounting surface mount electronics on the second two-layer circuit pair.

17. The method of claim 16.

18. the first two-layer circuit pair and the second two-layer circuit pair each include a pair of electrically conductive layers and an electrically insulating layer located between the electrically conductive layers; The method of claim 14.

19. the electrically conductive layer of the first two-layer circuit pair and the electrically conductive layer of the second two-layer circuit pair are etched; 20. The method of claim 18.

20. The laminate panel comprises: A laminate material; a plurality of power electronic device assemblies embedded within the laminate material; Equipped with The method of claim 13.

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