Cold plate equipment

Abstract

The present application relates to a cold plate having embedded power devices, driver circuits and microcontrollers and a 3D printed circuit board. The integrated power electronic package includes a cold plate having a microcontroller, a driver circuit and a power module embedded within the top surface of the cold plate. The 3D printed circuit board is printed on and / or around the microcontroller, the driver circuit and the power module to establish electrical connections between the components. Additional electrical components are mounted to the 3D printed circuit board to form an integrated power electronic package. The cold plate also includes a hollow internal groove having a plurality of fins. The plurality of fins have different densities to allow for targeted cooling of the microcontroller, the driver circuit and the power module embedded in the cold plate.

Description

Technical Field

[0001] The present description relates generally to cooling devices for embedded electronic devices and, more particularly, to cold plates and methods of forming cold plates. Background Art

[0002] In electrified vehicles, such as autonomous vehicles for mobility services, compactness of the electric drive train may be desired. As integrated power electronics gradually move from silicon ("Si") devices to silicon carbide ("SiC") devices, the heat flux of the devices increases due to the reduction in device footprint, which creates a need for aggressive cooling. In these power electronic devices, each layer between the heat source (power device) and the heat sink (cold plate) affects the overall thermal resistance of the device. In addition, power electronic devices often have other components that generate heat and may require cooling, such as driver integrated circuits ("ICs") and microcontrollers. Therefore, compact integrated power devices with embedded power devices and electronic components, as well as cold plates for cooling such power devices and electronic components, may be desired. Summary of the invention

[0003] In an embodiment, a device is disclosed. The device may include a cold plate having a plurality of cavities formed in a top surface of the cold plate. At least one microcontroller may be coupled to at least one of the plurality of cavities such that the at least one microcontroller is embedded in the top surface of the cold plate. At least one integrated circuit may be coupled to at least one of the plurality of cavities such that the at least one integrated circuit is embedded in the top surface of the cold plate. At least one power module may be coupled to at least one of the plurality of cavities such that the at least one power module is embedded in the top surface of the cold plate. The at least one microcontroller, the at least one integrated circuit, and the at least one power module are connected via a 3D printed circuit board formed on the top surface of the cold plate.

[0004] In another embodiment, an apparatus is disclosed. The apparatus may include a cold plate having at least one microcontroller, at least one integrated circuit, and at least one power module embedded in a top surface of the cold plate. The cold plate may also have a hollow interior recess positioned below the top surface of the cold plate, and a plurality of fins may be positioned within the hollow interior recess of the cold plate. An inlet and an outlet may be fluidly coupled to the hollow interior recess of the cold plate. The density of the plurality of fins may vary throughout the hollow interior recess of the cold plate.

[0005] Additionally, a method is disclosed. The method may include forming a cold plate having a plurality of cavities in a top surface of the cold plate. The method may also include embedding at least one microcontroller in at least one of the plurality of cavities, embedding at least one integrated circuit in at least one of the plurality of cavities, and embedding at least one power module in at least one of the plurality of cavities. The method may also include printing a circuit board on and / or around the at least one microcontroller, the at least one integrated circuit, and the at least one power module embedded in the top surface of the cold plate using a 3D printer.

[0006] These and additional features provided by the embodiments described herein will be more fully understood in view of the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The embodiments illustrated 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 the illustrative embodiments may be understood when read in conjunction with the following drawings, in which like structures are indicated by like reference numerals, and in which:

[0008] Figure 1 depicts an illustrative system having an electronic controller for forming an integrated power electronics package by 3D printing a control board onto a cold plate in accordance with one or more embodiments shown and described herein;

[0009] Figure 2 depicts a flow chart of an illustrative method for forming an integrated power electronic package by forming a cold plate according to one or more embodiments shown and described herein;

[0010] Figure 3 depicts a perspective view of an illustrative cold plate formed in accordance with one or more embodiments shown and described herein;

[0011] Figure 4 Depicts an embodiment according to one or more embodiments shown and described herein. Figure 3 A partial exploded view of the cold plate;

[0012] Figure 5 Depicts an embodiment according to one or more embodiments shown and described herein. Figure 3 A perspective view of the cold plate;

[0013] Figure 6 Depicts an embodiment according to one or more embodiments shown and described herein. Figure 3 A perspective view of a cold plate with a 3D printed circuit board; and

[0014] Figure 7Depicted is a flip chip packaging structure for connecting a 3D printed circuit board and a cold plate according to one or more embodiments described herein. DETAILED DESCRIPTION

[0015] Embodiments disclosed herein relate to cold plates, devices including cold plates, and methods of forming cold plates. More specifically, the present disclosure relates to cold plates having a plurality of fins configured to cool power devices and electronic components embedded in the cold plate. In some embodiments, the cold plate may include power devices, microcontrollers, driver ICs, and / or other power electronic components. In these embodiments, the cold plate may include a plurality of cavities that may be configured to accommodate at least a portion of the power devices and electronic components therein so that the components are at least partially embedded in the cold plate. The cold plate may be formed using conventional manufacturing methods or using additive manufacturing methods.

[0016] As described in more detail herein, 3D printed dielectric and conductor layers of a printed circuit board (PCB) can be formed on top of a cold plate to connect electronic components and power devices and lay out drivers, controller circuits, or other similar circuits in the PCB. In some embodiments, the electronic components can include a flip chip packaging structure, a ball grid array (BGA) structure, or a quad flat package (QFP) for connecting the components to the 3D printed PCB. Additional devices, such as resistors and capacitors, can be mounted to the 3D printed PCB.

[0017] The term "additive manufacturing" generally refers to a manufacturing process in which successive layers of material are provided, one upon the other, to build up a three-dimensional part layer by layer. The layers are typically fused together to form a monolithic part. Examples of additive manufacturing techniques include fused deposition modeling (FDM), selective laser sintering (SLS), 3D printing (such as inkjet and laser jet), stereolithography (SLA), direct laser sintering (DSLS), electron beam sintering (EBS), electron beam melting (EBM), laser engineered net shaping (LENS), laser net shaping manufacturing (LNSM), direct metal deposition (DMD), digital light processing (DLP), direct selective laser melting (DSLM), selective laser melting (SLM, direct metal laser melting (DMLM), etc. Additive manufacturing processes can allow a single part to be built using a variety of different materials.

[0018] As provided herein, the term "3D printing" may refer to an additive manufacturing process for creating a desired object (such as a cold plate or PCB) by stacking (e.g., printing) multiple layers of plastic, resin, metal, etc. to create a solid three-dimensional part. The 3D printing process may involve generating a digital model, such as a computer-aided design (CAD) model, which may be broken down into multiple horizontal layers to create a template for a 3D printer device to follow.

[0019] 3D printing may be particularly advantageous for the formation of cold plates. Notably, there is a growing need to manufacture cold plates that are more compact and more efficient than those achieved using conventional molding processes, which typically require multiple molding steps, such as molding, welding, etc. 3D printed cold plates can also provide higher thermal performance by utilizing complex geometries that are not achievable using conventional manufacturing techniques. For example, the achievable thickness of 3D printed cold plates is much smaller than those plates formed using conventional techniques. By utilizing smaller features, more complex flow channels can be created within the cold plate, increasing the total surface area of ​​the plate. The increase in surface area can in turn increase the amount of heat that can be carried away by the plate, thereby improving the thermal performance of the plate.

[0020] In addition, 3D printed cold plates can be lighter and more compact than conventionally formed cold plates. For example, the ability to form unique shapes and internal features provided by 3D printing allows the cold plate to use less material, making the plate lighter and more compact. In addition, the 3D printed cold plate can be formed as a monolithic structure so that the plate does not include any connecting parts, openings, etc. that may cause heat transfer losses or coolant (e.g., fluid) to escape. This is a significant improvement over conventionally formed cold plates, which are typically formed of at least two shells with multiple seals and / or joints that may be prone to leakage.

[0021] Finally, 3D printed cold plates benefit from simplified production processing. Notably, the processing of 3D printed cold plates reduces the need for expensive and time-consuming work such as forming, brazing, welding, and allows for streamlined cold plate production.

[0022] Utilizing 3D printed PCBs can offer similar advantages. Unlike traditional methods, lamination methods using laser drilling and electroplating, 3D printing the PCB directly onto a cold plate allows the PCB to have asymmetric geometries. For example, the process of 3D printing PCBs on and around electronic components described in detail in this article enables components to be seamlessly embedded into the PCB.

[0023] 3D printing equipment can be configured to deposit conductive, insulating and support materials to form PCBs without being constrained by the various limitations associated with traditional lamination methods. Alternatively, 3D printing equipment is capable of printing conductive materials and insulating materials in a single layer. In addition, 3D printing equipment is capable of changing all three dimensions of the conductive portion of the PCB in 3-dimensional space (e.g., in the X, Y and / or Z directions) when forming the conductive portion. Therefore, instead of forming a plurality of relatively small through holes between the conductive layers in the laminated PCB to provide a conductive and / or thermally conductive path, a 3D printed PCB can be formed with a single large conductive portion. The single large conductive portion reduces the resistance and thermal resistance paths within the PCB by eliminating unnecessary layers between the embedded power device and the cold plate or other heat dissipation surfaces of the PCB. In addition, the conductive paths formed using the 3D printing process are not limited to conductive planes, and are generally perpendicularly intersected (e.g., through holes) to interconnect parallel planes of conductive materials. That is, the 3D printed conductive paths formed in the 3D printed PCB can have any shape in the X, Y and Z directions, and are not constrained by the parallel planes and the vertical conductive through hole orientation. Therefore, 3D printed PCBs can be thinner and more efficient in terms of heat transfer through the 3D printed PCB compared to laminated PCBs.

[0024] As provided herein, the term "flip chip package" refers to an assembly whereby a semiconductor die, such as a microcontroller, microelectromechanical system (MEMS) or driver IC, is attached to a substrate or carrier with bonding pads facing down. In a flip chip package, electrical connections can be created with the aid of conductive bumps on the die pads. Once the die is connected, any space between the die and the substrate can be filled with a non-conductive adhesive commonly referred to as "bottom filler." The bottom filler can relieve stress between the die and the substrate and protect the electronic components from moisture intrusion.

[0025] Flip chip packaging can provide many advantages over alternative interconnect packaging. For example, flip chip packaging can provide higher input / output (I / O) counts because the entire area of ​​the die can be used for connections. In addition, because flip chip packaging uses short interconnect paths, the speed of devices using flip chip packaging can be increased. In addition, the elimination of wire bonding provides a flip chip package with a smaller form factor and increased thermal conductivity.

[0026] Traditional flip-chip packaging utilizes solder ball arrays to form electrical connections between the substrate and the die. However, the disclosed integrated power electronic package reduces the need for solder ball arrays by using 3D-printed through-holes of the PCB to connect the substrate to the electronic components embedded in the cold plate. By eliminating the solder ball arrays, the flip-chip packaging used herein can also minimize the interconnection paths, thereby improving the speed and thermal conductivity of the disclosed integrated power electronic package.

[0027] Embodiments of cold plates and systems and methods of forming integrated power electronic packages will now be described in greater detail herein.These systems, methods, and apparatus will be described in greater detail below with reference to the accompanying drawings, wherein like numerals represent like structures.

[0028] refer to Figure 1 , an illustrative system 100 with an electronic controller 102 is illustrated for forming an integrated power electronic package by 3D printing a PCB onto a cold plate. In some embodiments, the system 100 includes an electronic controller 102, such as a computing device communicatively coupled to a 3D printer 105. The electronic controller 102 may include a display 102a, a processing unit 102b, and an input device 102c, each of which may be communicatively coupled to one another. The electronic controller 102 may be a server, a personal computer, a laptop, a tablet, a smart phone, a handheld device, or a similar computing device. A user of the system may use the electronic controller 102 to provide information to the system. The electronic controller 102 may utilize a local application, a web application, or the like to access a 3D printer 105 communicatively coupled to the electronic controller 102 as described herein. The system may also include one or more data servers (not shown) having one or more databases from which the electronic controller 102 may query, extract, update, and / or use cold plate designs, 3D printing instructions, and the like (e.g., computer-aided design (CAD) files, etc.).

[0029] The electronic controller 102, described in more detail herein, may be configured to host applications and perform processing associated with the system described herein. Figure 1 The electronic controller 102 and the 3D printer 105 are depicted in the illustrative system 100 of , but each function and operation performed by the electronic controller 102 can be implemented and deployed in a distributed computing environment, which has multiple electronic controllers 102 and multiple 3D printers 105. It should also be understood that although the electronic controller 102 is described as a personal computer, this is only an example. In some embodiments, any type of computing device (e.g., a mobile computing device, a personal computer, a server, etc.) can be used for any of these components. In addition, in some embodiments, the electronic controller 102 can be a component of the 3D printer 105.

[0030] The electronic controller 102 includes a processor 130, input / output hardware 132, network interface hardware 134, a data storage component 136 that can store a database of PCB designs 138a and a database of 3D printer instructions corresponding to one or more of the PCB designs 138a, and a memory component 140. The memory component 140 can be a machine-readable memory (which can also be referred to as a non-transitory processor-readable memory). The memory component 140 can be configured as a volatile and / or non-volatile memory, and thus can include a random access memory (including SRAM, DRAM, and / or other types of random access memory), flash memory, registers, compact disks (CDs), digital versatile disks (DVDs), and / or other types of storage components. In addition, the memory component 140 can be configured to store operating logic 142, system logic 144a for implementing one or more methods described herein, and interface logic 144b for implementing an interactive interface between a user and the system 100 (each of which can be implemented as a computer program, firmware, or hardware as an example). The local interface 146 is also included in Figure 1 and may be implemented as a bus or other interface to facilitate communication between components of the electronic controller 102 .

[0031] The processor 130 may include any (one or more) processing components configured to receive and execute programming instructions (such as from the data storage component 136 and / or the memory component 140). The instructions may be in the form of a machine-readable instruction set stored in the data storage component 136 and / or the memory component 140. The input / output hardware 132 may include a monitor, keyboard 102c, mouse, printer, camera, microphone, speaker and / or other device for receiving, sending and / or presenting data. The network interface hardware 134 may include any wired or wireless networking hardware, such as a modem, LAN port, Wi-Fi card, WiMax card, mobile communication hardware and / or other hardware for communicating with other networks and / or devices.

[0032] It should be understood that the data storage component 136 may reside locally and / or remotely from the electronic controller 102 and may be configured to store one or more pieces of data for access by the electronic controller 102 and / or other components. Figure 1As shown in , the data storage component 136 can store a database of cold plate designs 138c, and a database of 3D printer instructions corresponding to one or more of the cold plate designs 138c. The data storage component 136 also includes a database of 3D printer instructions corresponding to one or more of the PCB designs 138a. The 3D printer instructions can be generated by the electronic controller 102 or another computing system. The 3D printer instructions include specific motion and deposition instructions for a predetermined 3D printer model so that the 3D printer builds a PCB according to the user-defined PCB design 138a.

[0033] The system 100 also includes a 3D printer 105 communicatively coupled to the electronic controller 102. The 3D printer 105 can be any rapid prototyping, rapid manufacturing or additive manufacturing equipment, such as a material jet (MJ), a binder jet (BJ), a drop-on-demand (DOD), a fused deposition modeling (FDM), a stereolithography (SLA), a digital light processing (DLP), a selective laser sintering (SLS), a selective laser melting (SLM), a laminated object manufacturing (LOM), an electron beam melting (EBM), etc. The 3D printer 105 can include a processor and a memory and other electronic components for receiving 3D printing instructions 138b for printing a PCB design 138a. The 3D printing instructions 138b are design configuration files corresponding to the PCB design 138a for printing that can be uploaded to the 3D printer 105.

[0034] In some embodiments, the system 100 can be implemented by interconnecting multiple devices, for example, through a network in which the electronic controller 102 and the 3D printer 105 can be co-located or in different locations. In other embodiments, the system 100 is implemented by the electronic controller 102 being communicatively coupled to the 3D printer 105. According to the embodiments shown and described herein, regardless of the implementation of the system 100, the electronic controller 102 can utilize hardware, software, and / or firmware. Although in some embodiments, the electronic controller 102 can be configured as a general-purpose computer with the necessary hardware, software, and / or firmware, in some embodiments, the electronic controller 102 can be configured as a special-purpose computer specifically designed to perform the functions described herein.

[0035] Still reference Figure 1, the system 100 can also be configured to 3D print the cold plate. In these embodiments, the data storage component 136 can also include a database of cold plate designs 138c and / or a database of 3D printer instructions corresponding to the plate designs 138c. The 3D printer instructions can be generated by the electronic controller 102 or another computing system. The 3D printer instructions include specific motion and deposition instructions for a predetermined 3D printer model so that the 3D printer builds a cold plate according to the user-defined cold plate design 138c.

[0036] In embodiments where the cold plate is 3D printed, the electronic controller 102 can be configured to implement 3D printing of the cold plate and PCB using the 3D printer 105. In these embodiments, the 3D printer 105 can 3D print the cold plate before printing the PCB layer onto the top surface of the cold plate. Once the cold plate is formed, the electronic controller can execute the 3D printer instructions to deposit the PCB on top of the cold plate, as described in detail herein.

[0037] Reference now Figure 2 , depicting an illustrative flow chart of an illustrative method for forming an integrated power electronic package including a cold plate. The method described herein produces an integrated power electronic package that improves thermal management of power electronic devices integrated therein. Initially, embedding power devices and electronic components (such as microcontrollers and driver ICs) into the top surface of the cold plate effectively enhances the cooling of these components during operation. It is worth noting that each layer between the power device and the cold plate affects the overall thermal resistance of the integrated power electronic package. Therefore, embedding the power device and electronic components into the top surface of the cold plate can have the effect of minimizing the number of layers that exist between the power device and the cold plate, thereby reducing the overall thermal resistance of the package.

[0038] Embodiments in which the cold plate is 3D printed may provide additional thermal management benefits. For example, the 3D printing method may produce a cold plate having a single monolithic structure that does not include a large number of seals and / or joints that are prone to leaking over time and inhibiting the thermal management of the cold plate. By 3D printing the cold plate as a single structure, such leakage issues may be mitigated. Additionally, methods of 3D printing the cold plate allow for the use of geometries that may not be possible with conventional manufacturing techniques. These unique geometries may increase the total surface area of ​​the cold plate, which in turn may increase the amount of heat that the cold plate is able to transfer away from any embedded electronic components.

[0039] Similarly, these benefits can be achieved by forming the cold plate from a single piece of material, such as a thermally conductive material. In these embodiments, the cold plate can be formed via extrusion or another similar manufacturing technique.

[0040] Furthermore, methods of 3D printing PCBs on and / or around power devices embedded within a cold plate can provide additional thermal benefits. Specifically, 3D printing PCBs eliminates the need for a grease layer and / or other thermal interface layer between the PCB and the cold plate and acts to reduce the need for an external insulation layer. Furthermore, 3D printed PCBs can be thinner and more efficient in heat transfer than conventional laminated PCBs.

[0041] A method 200 for forming an integrated power electronic package will now be described. Figure 2 At block 210, the method may include forming a cold plate, such as, for example Figure 3-Figure 4 . In some embodiments, the cold plate 300 can be formed using conventional manufacturing techniques, while in other embodiments, the cold plate 300 can be formed using a 3D printing process.

[0042] like Figure 4 As best shown in FIG. 3 , the cold plate 300 may include a plurality of cavities 304 positioned in the top surface 302 of the cold plate 300. The plurality of cavities 304 may be sized to accommodate one or more power modules 330, one or more microcontrollers 320, and / or one or more driver ICs 340. For example, the plurality of cavities 304 may include a power module cavity 304a sized to accommodate one or more power modules 330, a microcontroller cavity 304b sized to accommodate one or more microcontrollers 320, and a driver IC cavity 304c sized to accommodate one or more driver ICs 340.

[0043] In these embodiments, the plurality of cavities 304 may have a sufficient size and depth such that the power module 330, the microcontroller 320, and / or the driver IC 340 are embedded in the top surface 302 of the cold plate 300 when incorporated into the plurality of cavities 304. For example, the power module 330, the microcontroller 320, and / or the driver IC 340 may be embedded in the top surface 302 of the cold plate 300 such that the top surface of each component is flush with the top surface 302 of the cold plate 300.

[0044] refer to Figure 3 and Figure 4 , the cold plate 300 may also include an inlet 360 and an outlet 380, each of which may be configured to allow fluid and / or vapor (such as a coolant) to pass through the 3D printed cold plate 300. For example, the coolant may enter the cold plate 300 via the inlet 360 and exit the cold plate 300 via the outlet 380.

[0045] Now turn to Figure 5, shows a partially transparent view of the cold plate 300 illustrating the hollow interior recess of the cold plate 300. As shown, the cold plate 300 can be formed such that the cold plate 300 includes a hollow interior recess 310, which can accommodate various cooling components, such as, for example, a plurality of fins 312. Although Figure 5 The embodiment of FIG. 3 illustrates the cold plate 300 as including a plurality of fins 312 , but it should be understood that the cold plate 300 may also be designed to include other cooling features, such as a plurality of straight channels, pin fins, a manifold micro-channel structure, and the like.

[0046] In embodiments where the cold plate 300 is 3D printed, the fins 312 may be 3D printed as part of the cold plate 300 such that the fins 312 and the cold plate 300 are a single monolithic structure. In other embodiments, the fins 312 may be formed separately using conventional manufacturing methods such as machining, casting, extrusion, and other similar processes and then bonded to the cold plate 300, and more particularly, to the hollow interior recess 310. In such embodiments, the fins 312 may be bonded to the interior recess 310 by thermally conductive epoxy, brazing, welding, or a similar bond.

[0047] In some embodiments, the cold plate 300 can include multiple regions such that each region includes a plurality of fins 312 having a different density. As provided herein, the term "density" can refer to the compactness of the plurality of fins in each of the multiple regions of the cold plate 300. For example, the plurality of fins 312 can be positioned such that the fins 312 are tightly packed or dense in some regions of the cold plate 300 relative to the plurality of fins 312 being loosely packed or sparse in other regions of the cold plate 300. In these embodiments, the surface area of ​​the plurality of fins 312 may be greatest in regions where the fins 312 are densely deployed, which may result in increased heat transfer from these regions.

[0048] In these embodiments, the cold plate 300 can be configured to have different heat exchange properties in each of the multiple zones, which may be desirable for cooling different embedded electronic components in each of the multiple zones. Figure 5A plurality of sparsely deployed fins 312a positioned adjacent to a microcontroller 320 and a driver IC 340 and a plurality of densely deployed fins 312b positioned adjacent to a power module 330 are illustrated. In this embodiment, the power module 330 may generate significantly more heat than the microcontroller 320 and / or the driver IC 340, which increases the need for heat transfer from the power module 330. As the fluid flows through the internal recess 310 of the cold plate 300, the surface area of ​​the fluid that comes into contact with the plurality of fins 312 is greatest in the region corresponding to the plurality of densely packed fins 312b (e.g., the region adjacent to the power module 330), which in turn may increase the amount of heat transfer in that region. In these embodiments, the flow of fluid through the cold plate 300 may be optimized by controlling the density of the plurality of fins 312 in each region, which may help balance heat transfer and any potential pressure drop that may occur within the internal recess 310.

[0049] Still reference Figure 5 , the plurality of fins 312 in each of the plurality of regions can be configured to enhance heat transfer in single-phase cooling and two-phase cooling, depending on the cooling application for which the cold plate 300 is required. For example, in regions where a high degree of cooling is required, such as cooling of one or more power modules 330, the fins 312 can be configured as a two-phase cooling structure. In such a configuration, the fins 312 can be positioned adjacent to the one or more power modules 330 embedded in the cold plate 300. Thus, the heat generated by the one or more power modules 330 can cause a phase change of the fluid within the hollow interior recess 310 (e.g., boiling the fluid and converting it to vapor). The fluid may undergo another phase change on a surface within the hollow interior recess 310 (e.g., the vapor may condense) or exit the interior recess 310 through an outlet 380, which couples the interior recess 310 fluid to the external environment of the cold plate 300.

[0050] In other embodiments, the fins 312 can be configured to provide single-phase cooling of the cold plate 300. In these embodiments, the fins 312 can be porous or solid, depending on the application. The fins 312 can allow relatively unrestricted flow of fluid within the interior recess 310 of the cold plate 300, so that heat transfer occurs via the fluid from the power module 330, microcontroller 320, and / or driver IC 340 embedded in the cold plate 300. In a single-phase configuration, the temperature of the fluid flowing through and / or around the fins 312 may increase, but will generally remain in liquid form. Once the fluid flows through and / or around the fins 312, the fluid can leave the interior recess 310 of the cold plate 300 through the outlet 380.

[0051] Reference now Figure 2At block 220, a sub-process of assembling the power module 330 is completed so that the power module 330 can be bonded to a concave surface within the cavity 304 of the cold plate 300. As provided herein, the concave surface can be a surface within the top surface 302 of the cold plate 300 and can have a sufficient depth so that the power module 330 bonded thereto is flush with the top surface 302 of the cold plate 300. In some embodiments, the power module 330 can include a power device 332, a conductive substrate 334, and an electrically insulating layer 336, such as Figure 4 In some embodiments, the conductor substrate 334 may include a bulk copper component or any other suitable conductor, such as an S-cell.

[0052] The electrical insulating layer 336 may be a directly bonded copper (DBC) layer. It should be understood that in these embodiments, the DBC layer is implemented because of its excellent electrical insulation and good thermal diffusion properties. Thus, other devices having electrical insulation and thermal diffusion properties similar to or better than those of the DBC layer may be implemented to replace the DBC layer contemplated herein.

[0053] In addition, the power device 332 may include, for example, one or more semiconductor devices, such as, but not limited to, an insulated gate bipolar transistor (IGBT), a reverse conducting IGBT (RC-IGBT), a metal-oxide semiconductor field effect transistor (MOSFET), a power MOSFET, a diode, a transistor, and / or a combination thereof. The power device 332 may be formed using micro-electromechanical systems (MEMS) technology, which involves the use of microfabrication techniques to create miniaturized mechanical and / or electromechanical devices (e.g., sensors, actuators, electronic devices, etc.) and structures.

[0054] To form the power module 330, the power device 332, the conductor substrate 334, and the electrically insulating layer 336 can all be bonded together. In some embodiments, the conductor substrate 334 includes an opening for accommodating the power device 332. In these embodiments, the power device 332 can be bonded to the opening of the conductor substrate 334 using silver sintering or other bonding techniques such as transient liquid phase (TLP) bonding. The conductor substrate 334 and the power device 332 can then be bonded to the electrically insulating layer 336 using similar bonding techniques. It should be noted that in other embodiments, the conductor substrate 334 and the electrically insulating layer 336 can be bonded together before the power device 332 is bonded into the opening of the conductor substrate.

[0055] Now go to Figure 2At block 230, the method may further include manufacturing microcontroller 320 and driver IC 340. Microcontroller 320 may be formed using conventional methods, such as very large scale integration (VLSI) manufacturing, which may involve combining multiple transistors into a single controller. Driver IC 340 may also be formed using conventional manufacturing techniques such as photolithography, etching, deposition, etc.

[0056] Once the power module 330, microcontroller 320, and driver IC 340 are manufactured, these components can be bonded to the concave surface of the cavity 304 of the cold plate 300 so that each component is embedded in the top surface 302 of the cold plate 300, as shown in FIG. Figure 2 In some embodiments, the power module 330 can be bonded to the concave surface of the cavity 304 by bonding the electrically insulating layer 336 of the power module 330 into the cavity 304 of the cold plate 300. In these embodiments, the power module 330 can be sintered, welded, TLP bonded, or similarly bonded to the cold plate.

[0057] Reference now Figure 3-Figure 4 In some embodiments, the microcontroller 320 and the driver IC 340 may have a flip chip packaging structure. In these embodiments, the bottom surface of the microcontroller 320 may include multiple signal paths, which may include multiple I / O connections, and the top surface of the microcontroller 320 may include multiple thermal paths. Similarly, the bottom surface of the driver IC 340 may include multiple signal paths, which may include multiple I / O connections, and the top surface of the driver IC may include multiple thermal paths.

[0058] When the microcontroller 320 and the driver IC 340 are bonded to the concave surface of the cavity 304 of the cold plate 300, the components can be flipped so that the top surface of each component (e.g., the surface including the plurality of thermal paths) contacts the concave surface of the cavity 304. In this configuration, the bottom surface of each component (e.g., the surface including the plurality of I / O connections) faces the top surface 302 of the cold plate 300. In these embodiments, the bottom surfaces of the microcontroller 320 and the driver IC 340 can be flush with the top surface 302 of the cold plate 300. Once the microcontroller 320 and the driver IC are bonded to the cold plate 300, the plurality of I / O connections on the bottom surfaces of the microcontroller 320 and the driver IC 340 can be exposed. In this configuration, the plurality of I / O connections can be connected to the power module 330 and the 3D printed PCB through the plurality of 3D printed through-holes.

[0059] The flip chip package structure described herein provides multiple benefits over conventional interconnect packages (such as traditional QFP or BGA packages). It is noteworthy that these conventional packages include thermal paths and signal paths on the same surface of the package. In these packages, wires may be required to connect the signal path to the circuit board. In addition, additional cooling may be required to effectively transfer heat from the thermal path. Additional wiring may greatly increase the inductance of the package, which in turn reduces the efficiency of heat dissipation from the package. These problems are alleviated by providing the microcontroller 320 and the driver IC 340 in a flip chip package, which involves isolating the thermal path and the signal path on separate surfaces, as described herein. By isolating the paths on separate surfaces, the thermal paths of the microcontroller 320 and the driver IC 340 may be able to benefit from the heat transfer provided by the fluid flowing through the internal groove 310 of the cold plate, which can reduce the need for additional cooling. At the same time, the signal paths of the microcontroller 320 and the driver IC 340 may remain exposed so that the paths may be connected to the power module 330 and the 3D printed PCB via 3D printed vias, thereby eliminating the need for any additional electrical wiring.

[0060] The flip chip packaging of the microcontroller 320 and the driver IC 340 further serves to eliminate the need for solder ball arrays, which are typically used in conventional flip chip packaging to establish electrical connections between control circuits and / or power devices and the signal paths of the package. By 3D printing a PCB directly onto the top surface 302 of the cold plate 300, a seamless electrical connection can be created between the multiple I / O connections on the microcontroller 320 and the driver IC 340. By exchanging conventional solder ball arrays for 3D printed through-holes, the flip chip packaging described herein can further reduce the inductance of the package, which in turn can increase the heat transfer efficiency of the entire package.

[0061] Once the microcontroller 320, driver IC 340 and power module 330 have been embedded into the cold plate 300, Figure 2 The method shown in FIG. 4 may further include 3D printing a PCB 400 on and / or around the power module 330 embedded in the cold plate 300, as shown in blocks 250 and Figure 6. The PCB 400 may include a plurality of conductive portions and insulating portions that are 3D printed on and / or around the microcontroller 320, the driver IC 340, and the power module 330. The conductive portion may include a plurality of conductive paths that are configured to interconnect the microcontroller 320, the driver IC 340, and the power module 330 of the cold plate 300. In addition, the conductive portion may also include a plurality of conductive pads that, in combination with the conductive paths, enable electrical connections from components mounted on the cold plate 300 to the microcontroller 320, the driver IC 340, and the power module 330 embedded within the cold plate 300.

[0062] It should be understood that, since the PCB 400 is 3D printed, the conductive pads of the printed PCB 400 do not include an intermediate insulating layer or through holes formed using laser drilling or other machining and plating techniques. As a result, the PCB 400 can be directly formed on the cold plate 300 and on and / or around the embedded microcontroller 320, driver IC 340, and power module 330. This can effectively eliminate the additional processing steps of processing cavities within the laminated PCB to accommodate the power module 330 and / or laser drilling and plating to form conductive and / or thermal conductive through holes.

[0063] Furthermore, by printing the conductive portions using a 3D printer, the process of printing the conductive material can include printing directly on the electrical connections of the microcontroller 320, the driver IC 340, and the power module 330, thereby forming a seamless electrical connection from the components to the conductive paths formed within the printed PCB 400. Conventional methods of forming PCBs are limited to a layer-by-layer process associated with lamination, which involves placing multiple relatively small vias between conductive layers within the PCB to provide electrical and / or thermal paths. In contrast, the 3D printed PCB 400 can be formed with a single large conductive portion, which reduces the electrical and thermal resistance paths within the PCB 400 and achieves the seamless electrical connection described herein.

[0064] Although Figure 2 The method contemplates incorporating the power module 330, the microcontroller 320, and the driver IC 340 into the cold plate 300 (block 240), and then 3D printing the PCB 400 on and / or around the power module 330, the microcontroller 320, and the driver IC 340 (block 250), but it should be understood that these steps can be completed in any order. For example, the PCB 400 can first be formed around a portion of the power module 330, the microcontroller 320, and / or the driver IC 340, and then the components are bonded to the cold plate 300.

[0065] Once the PCB 400 has been 3D printed onto the cold plate, Figure 2The method may further include mounting additional electrical components 500 to the PCB 400, as shown at block 260. In some embodiments, one or more passive and / or active electronic components 500 are mounted on the 3D printed PCB 400. The electronic components 500 may be mounted on the PCB 400 using a pick and place operation or manually soldered thereon. The electronic components 500 may also provide logic control and / or switching functions to and from the power module 330, microcontroller 320, and driver IC 340 embedded within the cold plate 300.

[0066] Figure 7 A side view of a cold plate 300 formed according to the methods described herein is depicted. The cold plate 300 includes a power module 330, a microcontroller 320, and a driver IC 340 embedded in a top surface 302 of the cold plate 300. In this embodiment, the microcontroller 320 and the driver IC 340 include a flip chip packaging structure, as described herein. The cold plate 300 also includes a 3D printed PCB 400, which is printed on and / or around the microcontroller 320, the driver IC 340, and the power module 330. Figure 7 As shown in , 3D printed through-holes are used to provide electrical connections between the microcontroller 320, the driver IC 340, and the power module 330, so that no additional interconnect components, such as conventional solder ball arrays, are required. The electronic component 500 is mounted to the 3D printed PCB 400, which further serves to provide electrical connections between the electronic component 500 and the microcontroller 320, the driver IC 340, and the power module 330.

[0067] In view of the foregoing, it should be appreciated that a device stack including a cold plate is described herein. The cold plate may include a top surface having a plurality of cavities for accommodating electronic components. In some embodiments, the plurality of cavities may be configured to accommodate a power module, a microcontroller, and / or a driver IC. In these embodiments, the plurality of cavities may have variable sizes and depths such that the power module, the microcontroller, and / or the driver IC may be embedded within the top surface of the cold plate when the components are incorporated into the plurality of cavities. The power module may include a conductor substrate, an electrically insulating layer, and a power device, which may be individually combined together to form a power module before the power module is incorporated into the plurality of cavities in the top surface of the cold plate. In some embodiments, the microcontroller and the driver IC may include a flip chip packaging structure. In these embodiments, the bottom surface of the microcontroller and the driver IC may include a plurality of signal paths, which may have a plurality of I / O connections. The top surface of the microcontroller and the driver IC may include a plurality of thermal paths. The microcontroller and the driver IC may be incorporated into the cold plate such that the top surface of the microcontroller and the driver IC is in contact with the plurality of cavities, while the bottom surface of the microcontroller and the driver IC is flush with the top surface of the cold plate. In some embodiments, the cold plate may include multiple regions, and multiple fins having different densities may be disposed within a hollow internal groove adjacent to each of the multiple regions. In these embodiments, multiple regions containing electrical components requiring less heat transfer may include multiple sparse fins, while regions containing electrical components requiring more heat transfer may include multiple dense fins. The cold plate may also include an inlet and an outlet, both of which may be fluidically coupled to the hollow internal groove of the cold plate. The fluid may flow into the inlet and flow through multiple fins positioned in the internal groove, thereby absorbing heat from the electronic components embedded in the cold plate before exiting the internal groove via the outlet. A 3D printed PCB may be provided on the top surface of the cold plate, and additional electronic components may be mounted to the 3D printed PCB. The cold plate may also include a hollow internal groove, which may include multiple fins. A method of forming an integrated power electronic package is also contemplated. The method may include manufacturing a cold plate having multiple cavities for accommodating electronic components. The method may also include separately manufacturing a power module, which may include combining a conductor substrate, an electrically insulating layer, and a power device together. In addition, the method may include separately manufacturing a microcontroller and a driver IC. Once these components are fabricated, the power modules, microcontrollers, and driver ICs can be incorporated into multiple cavities so that the components are embedded in the cold plate. The 3D printed PCB can then be printed on the top surface of the cold plate over and / or around the power modules, microcontrollers, and driver ICs. The method can finally include mounting additional electronic components onto the 3D printed PCB.

[0068] The terms used herein are only used for the purpose of describing specific aspects and are not intended to be limiting. As used herein, the singular forms "one", "an" and "the" are intended to include plural forms, including "at least one", unless the content clearly states otherwise. "Or" means "and / or". As used herein, the term "and / or" includes any and all combinations of one or more of the items listed in association. It should also be understood that when used in this specification, the terms "include" and / or "include" or "include" and / or "include" specify the presence of the features, regions, integers, steps, operations, elements and / or parts described, but do not exclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, parts and / or their groups. The term "or a combination thereof" refers to a combination including at least one of the aforementioned elements.

[0069] It should be noted that the terms "substantially" and "approximately" may be used herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.

[0070] Although specific embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter. In addition, although various aspects of the claimed subject matter have been described herein, these aspects need not be used in combination. Therefore, the appended claims are intended to cover all such changes and modifications within the scope of the claimed subject matter.

Claims

1. A cold plate device, comprising: a cold plate comprising a surface and a plurality of cavities formed in the surface; a plurality of power electronic devices, each of the plurality of power electronic devices being disposed in a corresponding one of the plurality of cavities; as well as A 3D printed circuit board is coupled to the surface of the cold plate and the plurality of power electronic devices such that a bottom surface of the 3D printed circuit board directly contacts each of the plurality of power electronic devices disposed within the plurality of cavities.

2. The cold plate apparatus of claim 1, wherein the plurality of power electronic devices comprises at least one microcontroller, at least one integrated circuit, and at least one power module.

3. The cold plate apparatus of claim 2, wherein the at least one power module comprises a conductor substrate, an electrical insulation layer, and a power device.

4. The cold plate apparatus of claim 2, wherein the at least one microcontroller comprises a flip chip packaging structure.

5. The cold plate apparatus of claim 2, wherein the at least one integrated circuit comprises a flip chip packaging structure.

6. The cold plate apparatus of claim 1, wherein the cold plate further comprises a hollow interior recess.

7. The cold plate apparatus of claim 6, wherein the cold plate further comprises an inlet and an outlet fluidly coupled to the hollow interior recess.

8. The cold plate apparatus of claim 7, wherein a plurality of fins are positioned within the hollow interior recess.

9. The cold plate apparatus of claim 8, wherein the plurality of fins are positioned within the hollow interior recess in a plurality of zones such that each of the plurality of zones includes a plurality of fins having a different compactness.

10. The cold plate apparatus of claim 1, further comprising one or more electrical components coupled to the 3D printed circuit board.

11. A cold plate device comprising: a cold plate having a plurality of power electronics embedded in a top surface of the cold plate; a hollow interior recess below the top surface of the cold plate; a plurality of fins positioned within the hollow interior recess of the cold plate; a 3D printed circuit board coupled to a surface of the cold plate and the plurality of power electronic devices such that a bottom surface of the 3D printed circuit board directly contacts each of the plurality of power electronic devices embedded within the top surface of the cold plate; an inlet and an outlet fluidly coupled to the hollow interior recess of the cold plate; Wherein a compactness of the plurality of fins varies throughout the hollow interior recess of the cold plate.

12. The cold plate apparatus of claim 11, wherein the plurality of power electronic devices include at least one microcontroller, at least one integrated circuit, and at least one power module connected via a 3D printed circuit board formed on the top surface of the cold plate.

13. The cold plate apparatus of claim 12, further comprising one or more electrical components mounted to the 3D printed circuit board.

14. The cold plate apparatus of claim 12, wherein the at least one power module comprises a conductor substrate, an electrical insulation layer, and a power device.

15. The cold plate apparatus of claim 12, wherein the at least one microcontroller comprises a flip chip packaging structure.

16. The cold plate apparatus of claim 12, wherein the at least one integrated circuit comprises a flip chip packaging structure.

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